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Sample records for intratracheally instilled stainless

  1. Biodistribution of gold nanoparticles following intratracheal instillation in mouse lung

    DEFF Research Database (Denmark)

    Sadauskas, Evaldas; Jacobsen, Nicklas R.; Danscher, Gorm

    2009-01-01

    Background The fate of gold nanoparticles, 2, 40 and 100 nm, administered intratracheally to adult female mice was examined. The nanoparticles were traced by autometallography (AMG) at both ultrastructural and light microscopic levels. Also, the gold content was quantified by inductively coupled...... plasma mass spectrometry (ICP-MS) and neutron activation analysis (NAA). The liver is the major site of deposition of circulating gold nanoparticles. Therefore the degree of translocation was determined by the hepatic deposition of gold. Mice were instilled with 5 intratracheal doses of gold...... repeatedly during 3 weeks, the load was substantial. Ultrastructurally, AMG silver enhanced gold nanoparticles were found in lysosome-/endosome-like organelles of the macrophages and analysis with AMG, ICP-MS and NAA of the liver revealed an almost total lack of translocation of nanoparticles. In mice given...

  2. Significance of Intratracheal Instillation Tests for the Screening of Pulmonary Toxicity of Nanomaterials.

    Science.gov (United States)

    Morimoto, Yasuo; Izumi, Hiroto; Yoshiura, Yukiko; Fujisawa, Yuri; Fujita, Katsuhide

    Inhalation tests are the gold standard test for the estimation of the pulmonary toxicity of respirable materials. Intratracheal instillation tests have been used widely, but they yield limited evidence of the harmful effects of respirable materials. We reviewed the effectiveness of intratracheal instillation tests for estimating the hazards of nanomaterials, mainly using research papers featuring intratracheal instillation and inhalation tests centered on a Japanese national project. Compared to inhalation tests, intratracheal instillation tests induced more acute inflammatory responses in the animal lung due to a bolus effect regardless of the toxicity of the nanomaterials. However, nanomaterials with high toxicity induced persistent inflammation in the chronic phase, and nanomaterials with low toxicity induced only transient inflammation. Therefore, in order to estimate the harmful effects of a nanomaterial, an observation period of 3 months or 6 months following intratracheal instillation is necessary. Among the endpoints of pulmonary toxicity, cell count and percentage of neutrophil, chemokines for neutrophils and macrophages, and oxidative stress markers are considered most important. These markers show persistent and transient responses in the lung from nanomaterials with high and low toxicity, respectively. If the evaluation of the pulmonary toxicity of nanomaterials is performed in not only the acute but also the chronic phase in order to avoid the bolus effect of intratracheal instillation and inflammatory-related factors that are used as endpoints of pulmonary toxicity, we speculate that intratracheal instillation tests can be useful for screening for the identification of the hazard of nanomaterials through pulmonary inflammation.

  3. Pulmonary toxicity of printer toner following inhalation and intratracheal instillation.

    Science.gov (United States)

    Morimoto, Yasuo; Oyabu, Takako; Horie, Masanori; Kambara, Tatsunori; Izumi, Hiroto; Kuroda, Etsushi; Creutzenberg, Otto; Bellmann, Bernd; Pohlmann, Gerhard; Schuchardt, Sven; Hansen, Tanja; Ernst, Heinrich

    2013-10-01

    The pulmonary effects of a finished toner were evaluated in intratracheal instillation and inhalation studies, using toners with external additives (titanium dioxide nanoparticles and amorphous silica nanoparticles). Rats received an intratracheal dose of 1 mg or 2 mg of toner and were sacrificed at 3 days, 1 week, 1 month, 3 months and 6 months. The toner induced pulmonary inflammation, as evidenced by a transient neutrophil response in the low-dose groups and persistent neutrophil infiltration in the high-dose groups. There were increased concentrations of heme oxygenase-1 (HO-1) as a marker of oxidative stress in the bronchoalveolar lavage fluid (BALF) and the lung. In a 90-day inhalation study, rats were exposed to well-dispersed toner (mean of MMAD: 3.76 µm). The three mass concentrations of toner were 1, 4 and 16 mg/m(3) for 13 weeks, and the rats were sacrificed at 6 days and 91 days after the end of the exposure period. The low and medium concentrations did not induce neutrophil infiltration in the lung of statistical significance, but the high concentration did, and, in addition, upon histopathological examination not only showed findings of inflammation but also of fibrosis in the lung. Taken together, the results of our studies suggest that toners with external additives lead to pulmonary inflammation and fibrosis at lung burdens suggest beyond the overload. The changes observed in the pulmonary responses in this inhalation study indicate that the high concentration (16 mg/m(3)) is an LOAEL and that the medium concentration (4 mg/m(3)) is an NOAEL.

  4. Long-term effects of intratracheally instilled 253EsCl3 in rats

    International Nuclear Information System (INIS)

    Ballou, J.E.; Dagle, G.E.; Morrow, W.

    1975-01-01

    ts administered 253 EsCl 3 by intratracheal instillation developed more bone tumors and fewer lung tumors than similar rats administered 239 Pu(NO 3 ) 4 . In explanation, it is suggested that 253 Es may irradiatete bone surface cells more effectively while 239 Pu may irradiate a greater total number of cells in the lung. (U.S.)

  5. Inflammogenic effect of well-characterized fullerenes in inhalation and intratracheal instillation studies

    Directory of Open Access Journals (Sweden)

    Yamamoto Kazuhiro

    2010-03-01

    Full Text Available Abstract Background We used fullerenes, whose dispersion at the nano-level was stabilized by grinding in nitrogen gas in an agitation mill, to conduct an intratracheal instillation study and an inhalation exposure study. Fullerenes were individually dispersed in distilled water including 0.1% Tween 80, and the diameter of the fullerenes was 33 nm. These suspensions were directly injected as a solution in the intratracheal instillation study. The reference material was nickel oxide in distilled water. Wistar male rats intratracheally received a dose of 0.1 mg, 0.2 mg, or 1 mg of fullerenes and were sacrificed after 3 days, 1 week, 1 month, 3 months, and 6 months. In the inhalation study, Wistar rats were exposed to fullerene agglomerates (diameter: 96 ± 5 nm; 0.12 ± 0.03 mg/m3; 6 hours/days for 5 days/week for 4 weeks and were sacrificed at 3 days, 1 month, and 3 months after the end of exposure. The inflammatory responses and gene expression of cytokine-induced neutrophil chemoattractants (CINCs were examined in rat lungs in both studies. Results In the intratracheal instillation study, both the 0.1 mg and 0.2 mg fullerene groups did not show a significant increase of the total cell and neutrophil count in BALF or in the expression of CINC-1,-2αβ and-3 in the lung, while the high-dose, 1 mg group only showed a transient significant increase of neutrophils and expression of CINC-1,-2αβ and -3. In the inhalation study, there were no increases of total cell and neutrophil count in BALF, CINC-1,-2αβ and-3 in the fullerene group. Conclusion These data in intratracheal instillation and inhalation studies suggested that well-dispersed fullerenes do not have strong potential of neutrophil inflammation.

  6. Pulmonary toxicity of well-dispersed cerium oxide nanoparticles following intratracheal instillation and inhalation

    Science.gov (United States)

    Morimoto, Yasuo; Izumi, Hiroto; Yoshiura, Yukiko; Tomonaga, Taisuke; Oyabu, Takako; Myojo, Toshihiko; Kawai, Kazuaki; Yatera, Kazuhiro; Shimada, Manabu; Kubo, Masaru; Yamamoto, Kazuhiro; Kitajima, Shinichi; Kuroda, Etsushi; Kawaguchi, Kenji; Sasaki, Takeshi

    2015-11-01

    We performed inhalation and intratracheal instillation studies of cerium dioxide (CeO2) nanoparticles in order to investigate their pulmonary toxicity, and observed pulmonary inflammation not only in the acute and but also in the chronic phases. In the intratracheal instillation study, F344 rats were exposed to 0.2 mg or 1 mg of CeO2 nanoparticles. Cell analysis and chemokines in bronchoalveolar lavage fluid (BALF) were analyzed from 3 days to 6 months following the instillation. In the inhalation study, rats were exposed to the maximum concentration of inhaled CeO2 nanoparticles (2, 10 mg/m3, respectively) for 4 weeks (6 h/day, 5 days/week). The same endpoints as in the intratracheal instillation study were examined from 3 days to 3 months after the end of the exposure. The intratracheal instillation of CeO2 nanoparticles caused a persistent increase in the total and neutrophil number in BALF and in the concentration of cytokine-induced neutrophil chemoattractant (CINC)-1, CINC-2, chemokine for neutrophil, and heme oxygenase-1 (HO-1), an oxidative stress marker, in BALF during the observation time. The inhalation of CeO2 nanoparticles also induced a persistent influx of neutrophils and expression of CINC-1, CINC-2, and HO-1 in BALF. Pathological features revealed that inflammatory cells, including macrophages and neutrophils, invaded the alveolar space in both studies. Taken together, the CeO2 nanoparticles induced not only acute but also chronic inflammation in the lung, suggesting that CeO2 nanoparticles have a pulmonary toxicity that can lead to irreversible lesions.

  7. Pulmonary toxicity of well-dispersed cerium oxide nanoparticles following intratracheal instillation and inhalation

    Energy Technology Data Exchange (ETDEWEB)

    Morimoto, Yasuo, E-mail: yasuom@med.uoeh-u.ac.jp; Izumi, Hiroto; Yoshiura, Yukiko; Tomonaga, Taisuke; Oyabu, Takako; Myojo, Toshihiko; Kawai, Kazuaki; Yatera, Kazuhiro [University of Occupational and Environmental Health (Japan); Shimada, Manabu; Kubo, Masaru [Hiroshima University (Japan); Yamamoto, Kazuhiro [National Institute of Advanced Industrial Science and Technology (AIST) (Japan); Kitajima, Shinichi [National Sanatorium Hoshizuka Keiaien (Japan); Kuroda, Etsushi [Osaka University, Laboratory of Vaccine Science, WPI Immunology Frontier Research Center (Japan); Kawaguchi, Kenji; Sasaki, Takeshi [National Institute of Advanced Industrial Science and Technology (AIST) (Japan)

    2015-11-15

    We performed inhalation and intratracheal instillation studies of cerium dioxide (CeO{sub 2}) nanoparticles in order to investigate their pulmonary toxicity, and observed pulmonary inflammation not only in the acute and but also in the chronic phases. In the intratracheal instillation study, F344 rats were exposed to 0.2 mg or 1 mg of CeO{sub 2} nanoparticles. Cell analysis and chemokines in bronchoalveolar lavage fluid (BALF) were analyzed from 3 days to 6 months following the instillation. In the inhalation study, rats were exposed to the maximum concentration of inhaled CeO{sub 2} nanoparticles (2, 10 mg/m{sup 3}, respectively) for 4 weeks (6 h/day, 5 days/week). The same endpoints as in the intratracheal instillation study were examined from 3 days to 3 months after the end of the exposure. The intratracheal instillation of CeO{sub 2} nanoparticles caused a persistent increase in the total and neutrophil number in BALF and in the concentration of cytokine-induced neutrophil chemoattractant (CINC)-1, CINC-2, chemokine for neutrophil, and heme oxygenase-1 (HO-1), an oxidative stress marker, in BALF during the observation time. The inhalation of CeO{sub 2} nanoparticles also induced a persistent influx of neutrophils and expression of CINC-1, CINC-2, and HO-1 in BALF. Pathological features revealed that inflammatory cells, including macrophages and neutrophils, invaded the alveolar space in both studies. Taken together, the CeO{sub 2} nanoparticles induced not only acute but also chronic inflammation in the lung, suggesting that CeO{sub 2} nanoparticles have a pulmonary toxicity that can lead to irreversible lesions.

  8. Acute Pathophysiological Effects of Intratracheal Instillation of Budesonide and Exogenous Surfactant in a Neonatal Surfactant-depleted Piglet Model

    Directory of Open Access Journals (Sweden)

    Chia-Feng Yang

    2010-08-01

    Conclusions: Intratracheal instillation of surfactant or surfactant plus budesonide can improve oxygenation and pulmonary histologic outcome in neonatal surfactant-depleted lungs. The additional use of budesonide does not disturb the function of the exogenous surfactant. Intratracheal administration of a corticosteroid combined with surfactant may be an effective method for alleviating local pulmonary inflammation in severe RDS.

  9. Pulmonary toxicity of well-dispersed titanium dioxide nanoparticles following intratracheal instillation

    Energy Technology Data Exchange (ETDEWEB)

    Yoshiura, Yukiko, E-mail: y-yoshiura@med.uoeh-u.ac.jp; Izumi, Hiroto [University of Occupational and Environmental Health, Department of Occupational Pneumology, Institute of Industrial Ecological Science (Japan); Oyabu, Takako [University of Occupational and Environmental Health, Department of Environmental Health Engineering, Institute of Industrial Ecological Sciences (Japan); Hashiba, Masayoshi; Kambara, Tatsunori [University of Occupational and Environmental Health, Department of Occupational Pneumology, Institute of Industrial Ecological Science (Japan); Mizuguchi, Yohei; Lee, Byeong Woo; Okada, Takami [University of Occupational and Environmental Health, Department of Environmental Health Engineering, Institute of Industrial Ecological Sciences (Japan); Tomonaga, Taisuke [University of Occupational and Environmental Health, Department of Occupational Pneumology, Institute of Industrial Ecological Science (Japan); Myojo, Toshihiko [University of Occupational and Environmental Health, Department of Environmental Health Engineering, Institute of Industrial Ecological Sciences (Japan); Yamamoto, Kazuhiro [National Institute of Advanced Industrial Science and Technology (AIST) (Japan); Kitajima, Shinichi [National Sanatorium Hoshizuka Keiaien (Japan); Horie, Masanori [National Institute of Advanced Industrial Science and Technology (AIST), Health Research Institute (HRI) (Japan); Kuroda, Etsushi [Osaka University, Laboratory of Vaccine Science, WPI Immunology Frontier Research Center (Japan); Morimoto, Yasuo [University of Occupational and Environmental Health, Department of Occupational Pneumology, Institute of Industrial Ecological Science (Japan)

    2015-06-15

    In order to investigate the pulmonary toxicity of titanium dioxide (TiO{sub 2}) nanoparticles, we performed an intratracheal instillation study with rats of well-dispersed TiO{sub 2} nanoparticles and examined the pulmonary inflammation and histopathological changes in the lung. Wistar Hannover rats were intratracheally administered 0.2 mg (0.66 mg/kg) and 1.0 mg (3.3 mg/kg) of well-dispersed TiO{sub 2} nanoparticles (P90; diameter of agglomerates: 25 nm), then the pulmonary inflammation responses were examined from 3 days to 6 months after the instillation, and the pathological features were examined up to 24 months. Transient inflammation and the upregulation of chemokines in the broncho-alveolar lavage fluid were observed for 1 month. No respiratory tumors or severe fibrosis were observed during the recovery time. These data suggest that transient inflammation induced by TiO{sub 2} may not lead to chronic, irreversible legions in the lung, and that TiO{sub 2} nanoparticles may not have a high potential for lung disorder.

  10. Pulmonary toxicity of well-dispersed titanium dioxide nanoparticles following intratracheal instillation

    International Nuclear Information System (INIS)

    Yoshiura, Yukiko; Izumi, Hiroto; Oyabu, Takako; Hashiba, Masayoshi; Kambara, Tatsunori; Mizuguchi, Yohei; Lee, Byeong Woo; Okada, Takami; Tomonaga, Taisuke; Myojo, Toshihiko; Yamamoto, Kazuhiro; Kitajima, Shinichi; Horie, Masanori; Kuroda, Etsushi; Morimoto, Yasuo

    2015-01-01

    In order to investigate the pulmonary toxicity of titanium dioxide (TiO 2 ) nanoparticles, we performed an intratracheal instillation study with rats of well-dispersed TiO 2 nanoparticles and examined the pulmonary inflammation and histopathological changes in the lung. Wistar Hannover rats were intratracheally administered 0.2 mg (0.66 mg/kg) and 1.0 mg (3.3 mg/kg) of well-dispersed TiO 2 nanoparticles (P90; diameter of agglomerates: 25 nm), then the pulmonary inflammation responses were examined from 3 days to 6 months after the instillation, and the pathological features were examined up to 24 months. Transient inflammation and the upregulation of chemokines in the broncho-alveolar lavage fluid were observed for 1 month. No respiratory tumors or severe fibrosis were observed during the recovery time. These data suggest that transient inflammation induced by TiO 2 may not lead to chronic, irreversible legions in the lung, and that TiO 2 nanoparticles may not have a high potential for lung disorder

  11. Pulmonary toxicity of well-dispersed titanium dioxide nanoparticles following intratracheal instillation

    Science.gov (United States)

    Yoshiura, Yukiko; Izumi, Hiroto; Oyabu, Takako; Hashiba, Masayoshi; Kambara, Tatsunori; Mizuguchi, Yohei; Lee, Byeong Woo; Okada, Takami; Tomonaga, Taisuke; Myojo, Toshihiko; Yamamoto, Kazuhiro; Kitajima, Shinichi; Horie, Masanori; Kuroda, Etsushi; Morimoto, Yasuo

    2015-06-01

    In order to investigate the pulmonary toxicity of titanium dioxide (TiO2) nanoparticles, we performed an intratracheal instillation study with rats of well-dispersed TiO2 nanoparticles and examined the pulmonary inflammation and histopathological changes in the lung. Wistar Hannover rats were intratracheally administered 0.2 mg (0.66 mg/kg) and 1.0 mg (3.3 mg/kg) of well-dispersed TiO2 nanoparticles (P90; diameter of agglomerates: 25 nm), then the pulmonary inflammation responses were examined from 3 days to 6 months after the instillation, and the pathological features were examined up to 24 months. Transient inflammation and the upregulation of chemokines in the broncho-alveolar lavage fluid were observed for 1 month. No respiratory tumors or severe fibrosis were observed during the recovery time. These data suggest that transient inflammation induced by TiO2 may not lead to chronic, irreversible legions in the lung, and that TiO2 nanoparticles may not have a high potential for lung disorder.

  12. Changes in bronchoalveolar lavage cells after intratracheal instillation of dimethyl selenide in mice.

    Science.gov (United States)

    Cherdwongcharoensuk, Duangrudee; Upatham, Suchart; Oliveira, José Carlos; Sousa Pereira, António; AGuas, Artur P

    2004-01-01

    CD-1 mice were exposed to a single intratracheal instillation of either 0.025 or 0.075 mg Se/kg wt of dimethyl selenide (DMSe). They were studied over 4 weeks to define the cellular inflammatory response of the airways to DMSe. Bronchoalveolar (BAL) lavage was used to collect the DMSe-induced inflammatory exudates. The DMSe instillation resulted in phlogistic responses that had the neutrophil as the main leukocyte; they were present in BAL samples, mostly at days 1 and 7. Macrophages were also increased during DMSe-induced inflammation. The lower DMSe dose resulted in an inflammatory reaction lasting for 2 weeks. Mice treated with the higher DMSe dose still showed elevated numbers of neutrophils and macrophages 4 weeks after instillation. DMSe did not change the number of lymphocytes harvested from the airways. An early increase in total protein of BAL, and late enhancement in lactate dehydrogenase was observed in mice treated with the high DMSe dose. We conclude that inhalation of DMSe triggers a moderate and dose-dependent inflammatory reaction in the mouse airways, and that this phlogistic reaction is likely to participate in the damage of respiratory epithelia that occurs upon DMSe inhalation.

  13. Toxicity of Carbon Nanotubes in the Lungs of Mice 7 and 90 Days After Intratracheal Instillation

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    Lam, Chiu-Wing; James, John T.; McCluskey, Richard; Hunter, Robert L.

    2002-01-01

    Single-walled carbon nanotubes have many potential applications in the electronic, computer, and aerospace industries. Because unprocessed nanotubes could become airborne and potentially reach the lungs, their pulmonary toxicity was investigated. The three products studied were made by different methods, and contained different types and amounts of residual catalytic metals. Mice were each intratracheally instilled once with 0,0.1 or 0.5 mg of nanotubes, a carbon black negative control, or a quartz positive control, and killed for histopathological study 7 d or 90 d after the treatment. All nanotube products induced epithelioid granulomas and, in some cases, interstitial inflammation in the animals of the 7 -d groups. These lesions persisted and were worse in the 90-d groups. We found that, if nanotubes reach the lung, they can be more toxic than quartz, which is considered a serious occupational health hazard in chronic inhalation exposures.

  14. Cardiopulmonary responses of intratracheally instilled tire particles and constituent metal components

    Science.gov (United States)

    Gottipolu, R.R.; Landa, E.R.; Schladweiler, M.C.; McGee, J.K.; Ledbetter, A.D.; Richards, J.H.; Wallenborn, G.J.; Kodavanti, U.P.

    2008-01-01

    Tire and brake wear particles contain transition metals, and contribute to near-road PM. We hypothesized that acute cardiopulmonary injury from respirable tire particles (TP) will depend on the amount of soluble metals. Respirable fractions of two types of TP (TP1 and TP2) were analyzed for water and acid-leachable metals using ICP-AES. Both TP types contained a variety of transition metals, including zinc (Zn), copper (Cu), aluminum, and iron. Zn and Cu were detected at high levels in water-soluble fractions (TP2 > TP1). Male Wistar Kyoto rats (12-14 wk) were intratracheally instilled, in the first study, with saline, TP1 or TP2 (5 mg/kg), and in the second study, with soluble Zn, Cu (0.5 ??mol/kg), or both. Pulmonary toxicity and cardiac mitochondrial enzymes were analyzed 1 d, 1 wk, or 4 wk later for TP and 4 or 24 h later for metals. Increases in lavage fluid markers of inflammation and injury were observed at d 1 (TP2 > TP1), but these changes reversed by wk 1. No effects on cardiac enzymes were noted with either TP. Exposure of rats to soluble Zn and Cu caused marked pulmonary inflammation and injury but temporal differences were apparent (Cu effects peaked at 4 h and Zn at 24 h). Instillation of Zn, Cu, and Zn+ Cu decreased the activity of cardiac aconitase, isocitrate dehydrogenase, succinate dehydrogenase, cytochrome-c-oxidase and superoxide dismutase suggesting mitochondrial oxidative stress. The observed acute pulmonary toxicity of TP could be due to the presence of water soluble Zn and Cu. At high concentrations these metals may induce cardiac oxidative stress. Copyright ?? Informa Healthcare USA, Inc.

  15. Pulmonary responses to printer toner particles in mice after intratracheal instillation.

    Science.gov (United States)

    Bai, Ru; Zhang, Lili; Liu, Ying; Meng, Li; Wang, Liming; Wu, Yan; Li, Wei; Ge, Cuicui; Le Guyader, Laurent; Chen, Chunying

    2010-12-15

    The release of ultrafine particles from office equipment is currently receiving great concerns due to its potential threat to human health when inhaled. Printer toner is one of the largest consumables in daily office work, and the particles released from printers and photocopiers may pose damage to respiratory system. In this study, we found the particles can be released into the surrounding environment during the printing process and the concentrations of PM(2.5) and PM(10) particles increased obviously. To evaluate the time-course pulmonary responses caused by toner particles, the toner suspension was instilled into the lungs of the male mice through intratracheally instillation every other day for four times and the pulmonary responses of the lung were monitored at days 9, 28, 56 and 84. Indeed, mice treated with toner particles displayed a slower body weight growth rate during the recovery phase. The total cell number in bronchoalveolar lavage fluids (BALF) of toner-exposed groups was much higher than the saline-treated groups. The total protein, lactate dehydrogenase and acid phosphatase in BALF exhibited significant changes (ptoner-exposed groups also exhibited significant changes (ptoner particles can adhere to the alveolar septal walls, then enter into the alveoli and cause pulmonary lesion. During the experimental period, particles phagocytosed by alveolar macrophages (AMs) led to an increase of both AMs number and apoptosis. The pulmonary stress still remained over time even with a clearance period for 12 weeks. These results indicate that exposure to toner particles can inhibit the normal growth of the mice and induce significant inflammatory responses and lesion in the lung tissues. The health and safety effects from working indoors in offices with fumes and particles released from photocopiers and printers need to be paid more attention. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  16. Lung deposition and extrapulmonary translocation of nano-ceria after intratracheal instillation

    International Nuclear Information System (INIS)

    He Xiao; Zhang Haifeng; Ma Yuhui; Bai Wei; Zhang Zhiyong; Ding Yayun; Zhao Yuliang; Chai Zhifang; Lu Kai

    2010-01-01

    The broad potential applications of manufactured nanomaterials call for urgent assessment of their environmental and biological safety. However, most of the previous work focused on the cell level performance; little was known about the consequences of nanomaterial exposure at the whole-body and organ levels. In the present paper, the radiotracer technique was employed to study the pulmonary deposition and the translocation to secondary target organs after ceria nanoparticles (nano-ceria) were intratracheally instilled into Wistar rats. It was found that 63.9 ± 8.2% of the instilled nano-ceria remained in the lung by 28 d postexposure and the elimination half-life was 103 d. At the end of the test period, only 1/8-1/3 of the daily elimination of nano-ceria from the lung was cleared via the gastrointestinal tract, suggesting that phagocytosis by alveolar macrophages (AMs) with subsequent removal towards the larynx was no longer the predominant route for the elimination of nano-ceria from the lung. The whole-body redistribution of nano-ceria demonstrated that the deposited nano-ceria could penetrate through the alveolar wall into the systemic circulation and accumulate in the extrapulmonary organs. In vitro study suggested that nano-ceria would agglomerate and form sediments in the bronchoalveolar aqueous surrounding while binding to protein would be conducive to the redispersion of nano-ceria. The decrease in the size of agglomerates might enhance the penetration of nano-ceria into the systemic circulation. Our findings suggested that the effect of nanomaterial exposure, even at low concentration, should be assessed because of the potential lung and systemic cumulative toxicity of the nanomaterials.

  17. Dose-dependent pulmonary response of well-dispersed titanium dioxide nanoparticles following intratracheal instillation

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    Oyabu, Takako [Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health, Department of Environmental Health Engineering (Japan); Morimoto, Yasuo, E-mail: yasuom@med.uoeh-u.ac.jp; Hirohashi, Masami; Horie, Masanori; Kambara, Tatsunori [Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health, Department of Occupational Pneumology (Japan); Lee, Byeong Woo [Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health, Department of Environmental Health Engineering (Japan); Hashiba, Masayoshi [Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health, Department of Occupational Pneumology (Japan); Mizuguchi, Yohei; Myojo, Toshihiko [Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health, Department of Environmental Health Engineering (Japan); Kuroda, Etsushi [Osaka University, Laboratory of Vaccine Science, WPI Immunology Frontier Research Center (Japan)

    2013-04-15

    In order to investigate the relationship between pulmonary inflammation and particle clearance of nanoparticles, and also their dose dependency, we performed an instillation study of well-dispersed TiO{sub 2} nanoparticles and examined the pulmonary inflammations, the particle clearance rate and histopathological changes. Wistar rats were intratracheally administered 0.1 mg (0.33 mg/kg), 0.2 mg (0.66 mg/kg), 1 mg (3.3 mg/kg), and 3 mg (10 mg/kg) of well-dispersed TiO{sub 2} nanoparticles (diameter of agglomerates: 25 nm), and the pulmonary inflammation response and the amount of TiO{sub 2} in the lung were determined from 3 days up to 12 months sequentially after the instillation. There were no increases of total cell or neutrophil counts in bronchoalveolar lavage fluid (BALF) in the 0.1 and the 0.2 mg-administered groups. On the other hand, mild infiltration of neutrophils was observed in the 1 and 3 mg-administered groups. Histopathological findings showed infiltration of neutrophils in the 1 and 3 mg-administered groups. Of special note, a granulomatous lesion including a local accumulation of TiO{sub 2} was observed in the bronchioli-alveolar space in the 3 mg-administered group. The biological half times of the TiO{sub 2} in the lung were 4.2, 4.4, 6.7, and 10.8 months in the 0.1, 0.2, 1, and 3 mg-administered groups, respectively. Neutrophil infiltration was observed as the particle clearance was delayed, suggesting that an excessive dose of TiO{sub 2} nanoparticles may induce pulmonary inflammation and clearance delay.

  18. Pulmonary Toxicity, Distribution, and Clearance of Intratracheally Instilled Silicon Nanowires in Rats

    Directory of Open Access Journals (Sweden)

    Jenny R. Roberts

    2012-01-01

    Full Text Available Silicon nanowires (Si NWs are being manufactured for use as sensors and transistors for circuit applications. The goal was to assess pulmonary toxicity and fate of Si NW using an in vivo experimental model. Male Sprague-Dawley rats were intratracheally instilled with 10, 25, 50, 100, or 250 μg of Si NW (~20–30 nm diameter; ~2–15 μm length. Lung damage and the pulmonary distribution and clearance of Si NW were assessed at 1, 3, 7, 28, and 91 days after-treatment. Si NW treatment resulted in dose-dependent increases in lung injury and inflammation that resolved over time. At day 91 after treatment with the highest doses, lung collagen was increased. Approximately 70% of deposited Si NW was cleared by 28 days with most of the Si NW localized exclusively in macrophages. In conclusion, Si NW induced transient lung toxicity which may be associated with an early rapid particle clearance; however, persistence of Si NW over time related to dose or wire length may lead to increased collagen deposition in the lung.

  19. Functional ability and fate of pulmonary alveolar macrophages after intratracheal instillation into rats

    International Nuclear Information System (INIS)

    Snipes, M.B.; Feddersen, D.; Mueller, H.L.; Guilmette, R.A.; Haley, P.J.

    1988-01-01

    Pulmonary alveolar macrophages (PAM) from donor rats were intratracheally instilled into recipient rats to determine if donor macrophages were functionally similar to the recipient's own macrophages. Recipient and donor (extrinsic) PAM were equivalent in their ability to phagocytize 1.7 μm and 3.9 μm latex microspheres in vivo and sensitized sheep red blood cells in vitro. Also, the extrinsic PAM appeared functionally equivalent to recipient PAM with respect to ability to translocate into interstitial tissue and migrate to the lung-associated lymph nodes (LALN). The recipient PAN appeared to phagocytize the extrinsic PAM, but the extrinsic PAM did not appear to phagocytize the recipient PAM. This could represent a different degree of physiological coordination of intrinsic and extrinsic PAM activities in the lung. Overall, results indicated that extrinsic PAM can live and function in the lungs of recipient rats, and perform most or all of the functions ascribed to recipient PAM. Results also support the hypothesis that PAM are able to move into the pulmonary interstitium and translocate to the LALM without the involvement of other pulmonary macrophages. (author)

  20. Quantitative biokinetics of titanium dioxide nanoparticles after intratracheal instillation in rats: Part 3.

    Science.gov (United States)

    Kreyling, Wolfgang G; Holzwarth, Uwe; Haberl, Nadine; Kozempel, Ján; Wenk, Alexander; Hirn, Stephanie; Schleh, Carsten; Schäffler, Martin; Lipka, Jens; Semmler-Behnke, Manuela; Gibson, Neil

    2017-05-01

    The biokinetics of a size-selected fraction (70 nm median size) of commercially available and 48 V-radiolabeled [ 48 V]TiO 2 nanoparticles has been investigated in healthy adult female Wistar-Kyoto rats at retention time-points of 1 h, 4 h, 24 h, 7 d and 28 d after intratracheal instillation of a single dose of an aqueous [ 48 V]TiO 2 -nanoparticle suspension. A completely balanced quantitative biodistribution in all organs and tissues was obtained by applying typical [ 48 V]TiO 2 -nanoparticle doses in the range of 40-240 μg·kg -1 bodyweight and making use of the high sensitivity of the radiotracer technique. The [ 48 V]TiO 2 -nanoparticle content was corrected for residual blood retained in organs and tissues after exsanguination and for 48 V-ions not bound to TiO 2 -nanoparticles. About 4% of the initial peripheral lung dose passed through the air-blood-barrier after 1 h and were retained mainly in the carcass (4%); 0.3% after 28 d. Highest organ fractions of [ 48 V]TiO 2 -nanoparticles present in liver and kidneys remained constant (0.03%). [ 48 V]TiO 2 -nanoparticles which entered across the gut epithelium following fast and long-term clearance from the lungs via larynx increased from 5 to 20% of all translocated/absorbed [ 48 V]TiO 2 -nanoparticles. This contribution may account for 1/5 of the nanoparticle retention in some organs. After normalizing the fractions of retained [ 48 V]TiO 2 -nanoparticles to the fraction that reached systemic circulation, the biodistribution was compared with the biodistributions determined after IV-injection (Part 1) and gavage (GAV) (Part 2). The biokinetics patterns after IT-instillation and GAV were similar but both were distinctly different from the pattern after intravenous injection disproving the latter to be a suitable surrogate of the former applications. Considering that chronic occupational inhalation of relatively biopersistent TiO 2 -particles (including nanoparticles) and accumulation in

  1. Cardiovascular effects in rats after intratracheal instillation of metal welding particles.

    Science.gov (United States)

    Zheng, Wen; Antonini, James M; Lin, Yen-Chang; Roberts, Jenny R; Kashon, Michael L; Castranova, Vincent; Kan, Hong

    2015-01-01

    Studies have indicated that pulmonary exposure to welding fumes can induce a series of adverse effects in the respiratory system, including infection, bronchitis, siderosis and decreased pulmonary function. Recent clinical and epidemiological studies have found that pulmonary exposure to welding fumes is also associated with a higher incidence of cardiovascular events. However, there is insufficient evidence to confirm a direct effect of welding fumes on the cardiovascular system. The present study investigated the effects of pulmonary exposure to welding fumes on the heart and the vascular system in rats. Two chemically distinct welding fumes generated from manual metal arc-hard surfacing (MMA-HS) and gas metal arc-mild steel (GMA-MS) welding were tested. Three groups of rats were instilled intratracheally with MMA-HS (2 mg/rat), GMA-MS (2 mg/rat) or saline as control once a week for seven weeks. On days 1 and 7 after the last treatment, basal cardiovascular function and the cardiovascular response to increasing doses of adrenoreceptor agonists were assessed. MMA-HS treatment reduced the basal levels of left ventricle end-systolic pressure and dP/dt(max) at 1 day post-treatment, and decreased dP/dt(min) in response to isoproterenol (ISO) at 7 days post-treatment. Unlike MMA-HS, GMA-MS only affected left ventricular end-diastolic pressure in response to ISO at 7 days post-treatment. Treatment with MMA-HS or GMA-MS did not alter heart rate and blood pressure. Our findings suggest that exposure to different welding fumes can induce different adverse effects on the cardiovascular system, and that cardiac contractility may be a sensitive indicator of cardiovascular dysfunction.

  2. Acute inflammatory responses of nanoparticles in an intra-tracheal instillation rat model.

    Science.gov (United States)

    Armstead, Andrea L; Minarchick, Valerie C; Porter, Dale W; Nurkiewicz, Timothy R; Li, Bingyun

    2015-01-01

    Exposure to hard metal tungsten carbide cobalt (WC-Co) "dusts" in enclosed industrial environments is known to contribute to the development of hard metal lung disease and an increased risk for lung cancer. Currently, the influence of local and systemic inflammation on disease progression following WC-Co exposure remains unclear. To better understand the relationship between WC-Co nanoparticle (NP) exposure and its resultant effects, the acute local pulmonary and systemic inflammatory responses caused by WC-Co NPs were explored using an intra-tracheal instillation (IT) model and compared to those of CeO2 (another occupational hazard) NP exposure. Sprague-Dawley rats were given an IT dose (0-500 μg per rat) of WC-Co or CeO2 NPs. Following 24-hr exposure, broncho-alveolar lavage fluid and whole blood were collected and analyzed. A consistent lack of acute local pulmonary inflammation was observed in terms of the broncho-alveolar lavage fluid parameters examined (i.e. LDH, albumin, and macrophage activation) in animals exposed to WC-Co NP; however, significant acute pulmonary inflammation was observed in the CeO2 NP group. The lack of acute inflammation following WC-Co NP exposure contrasts with earlier in vivo reports regarding WC-Co toxicity in rats, illuminating the critical role of NP dose and exposure time and bringing into question the potential role of impurities in particle samples. Further, we demonstrated that WC-Co NP exposure does not induce acute systemic effects since no significant increase in circulating inflammatory cytokines were observed. Taken together, the results of this in vivo study illustrate the distinct differences in acute local pulmonary and systemic inflammatory responses to NPs composed of WC-Co and CeO2; therefore, it is important that the outcomes of pulmonary exposure to one type of NPs may not be implicitly extrapolated to other types of NPs.

  3. Acute Inflammatory Responses of Nanoparticles in an Intra-Tracheal Instillation Rat Model

    Science.gov (United States)

    Armstead, Andrea L.; Minarchick, Valerie C.; Porter, Dale W.; Nurkiewicz, Timothy R.; Li, Bingyun

    2015-01-01

    Exposure to hard metal tungsten carbide cobalt (WC-Co) “dusts” in enclosed industrial environments is known to contribute to the development of hard metal lung disease and an increased risk for lung cancer. Currently, the influence of local and systemic inflammation on disease progression following WC-Co exposure remains unclear. To better understand the relationship between WC-Co nanoparticle (NP) exposure and its resultant effects, the acute local pulmonary and systemic inflammatory responses caused by WC-Co NPs were explored using an intra-tracheal instillation (IT) model and compared to those of CeO2 (another occupational hazard) NP exposure. Sprague-Dawley rats were given an IT dose (0-500 μg per rat) of WC-Co or CeO2 NPs. Following 24-hr exposure, broncho-alveolar lavage fluid and whole blood were collected and analyzed. A consistent lack of acute local pulmonary inflammation was observed in terms of the broncho-alveolar lavage fluid parameters examined (i.e. LDH, albumin, and macrophage activation) in animals exposed to WC-Co NP; however, significant acute pulmonary inflammation was observed in the CeO2 NP group. The lack of acute inflammation following WC-Co NP exposure contrasts with earlier in vivo reports regarding WC-Co toxicity in rats, illuminating the critical role of NP dose and exposure time and bringing into question the potential role of impurities in particle samples. Further, we demonstrated that WC-Co NP exposure does not induce acute systemic effects since no significant increase in circulating inflammatory cytokines were observed. Taken together, the results of this in vivo study illustrate the distinct differences in acute local pulmonary and systemic inflammatory responses to NPs composed of WC-Co and CeO2; therefore, it is important that the outcomes of pulmonary exposure to one type of NPs may not be implicitly extrapolated to other types of NPs. PMID:25738830

  4. [Clinical efficacy of porcine pulmonary surfactant combined with budesonide suspension intratracheal instillation in the treatment of neonatal meconium aspiration syndrome].

    Science.gov (United States)

    Tan, Xiu-Zhen; Wu, Shi-Guang; Zhang, Jian-Hua; Li, Xiao-Fen; Gao, Ping-Ming; Wang, Yu

    2016-12-01

    To study the clinical efficacy of porcine pulmonary surfactant (PS) combined with budesonide suspension intratracheal instillation in the treatment of neonatal meconium aspiration syndrome (MAS). Seventy neonates with MAS were enrolled for a prospective study. The neonates were randomly assigned to PS alone treatment group and PS+budesonide treatment group (n=35 each). The PS alone treatment group was given PS (100 mg/kg) by intratracheal instillation. The treatment group was given budesonide suspension (0.25 mg/kg) combined with PS (100 mg/kg). The rate of repeated use of PS in the PS+ budesonide group was significantly lower than that in the PS alone group 12 hours after treatment (p<0.05). The improvement of PaO 2 /FiO 2 , TcSaO 2 , PaO 2 , and PaCO 2 in the PS+ budesonide group was significantly greater than that in the PS alone group 6, 12, and 24 hours after treatment (p<0.05). The chest X-ray examination showed that the pulmonary inflammation absorption in the PS+ budesonide group was significantly better than that in the PS alone group 48 hours after treatment (p<0.05). The incidence of complications in the PS+budesonide group was significantly lower than that in the PS alone group (p<0.05), and the average hospitalization duration was significantly shorter than that in the PS alone group (p<0.01). PS combined with budesonide suspension intratracheal instillation for the treatment of neonatal MAS is effective and superior to PS alone treatment.

  5. Genotoxicity of synthetic amorphous silica nanoparticles in rats following short-term exposure. Part 2: intratracheal instillation and intravenous injection.

    Science.gov (United States)

    Guichard, Yves; Maire, Marie-Aline; Sébillaud, Sylvie; Fontana, Caroline; Langlais, Cristina; Micillino, Jean-Claude; Darne, Christian; Roszak, Joanna; Stępnik, Maciej; Fessard, Valérie; Binet, Stéphane; Gaté, Laurent

    2015-03-01

    Synthetic amorphous silica nanomaterials (SAS) are extensively used in food and tire industries. In many industrial processes, SAS may become aerosolized and lead to occupational exposure of workers through inhalation in particular. However, little is known about the in vivo genotoxicity of these particulate materials. To gain insight into the toxicological properties of four SAS (NM-200, NM-201, NM-202, and NM-203), rats are treated with three consecutive intratracheal instillations of 3, 6, or 12 mg/kg of SAS at 48, 24, and 3 hrs prior to tissue collection (cumulative doses of 9, 18, and 36 mg/kg). Deoxyribonucleic acid (DNA) damage was assessed using erythrocyte micronucleus test and the standard and Fpg-modified comet assays on cells from bronchoalveolar lavage fluid (BALF), lung, blood, spleen, liver, bone marrow, and kidney. Although all of the SAS caused increased dose-dependent changes in lung inflammation as demonstrated by BALF neutrophilia, they did not induce any significant DNA damage. As the amount of SAS reaching the blood stream and subsequently the internal organs is probably to be low following intratracheal instillation, an additional experiment was performed with NM-203. Rats received three consecutive intravenous injections of 5, 10, or 20 mg/kg of SAS at 48, 24, and 3 hrs prior to tissue collection. Despite the hepatotoxicity, thrombocytopenia, and even animal death induced by this nanomaterial, no significant increase in DNA damage or micronucleus frequency was observed in SAS-exposed animals. It was concluded that under experimental conditions, SAS induced obvious toxic effects but did cause any genotoxicity following intratracheal instillation and intravenous injection. © 2014 Wiley Periodicals, Inc.

  6. The acute pulmonary and thrombotic effects of cerium oxide nanoparticles after intratracheal instillation in mice

    Directory of Open Access Journals (Sweden)

    Nemmar A

    2017-04-01

    Full Text Available Abderrahim Nemmar,1 Suhail Al-Salam,2 Sumaya Beegam,1 Priya Yuvaraju,2 Badreldin H Ali3 1Department of Physiology, 2Department of Pathology, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, UAE; 3Department of Pharmacology and Clinical Pharmacy, College of Medicine & Health Sciences, Sultan Qaboos University, Muscat, Al-Khod, Sultanate of Oman Abstract: Cerium oxide nanoparticles (CeO2 NPs, used as a diesel fuel catalyst, can be emitted into the ambient air, resulting in exposure to humans by inhalation. Recent studies have reported the development of lung toxicity after pulmonary exposure to CeO2 NPs. However, little is known about the possible thrombotic effects of these NPs. The present study investigated the acute (24 hours effect of intratracheal (IT instillation of either CeO2 NPs (0.1 or 0.5 mg/kg or saline (control on pulmonary and systemic inflammation and oxidative stress and thrombosis in mice. CeO2 NPs induced a significant increase of neutrophils into the bronchoalveolar lavage (BAL fluid with an elevation of tumor necrosis factor α (TNFα and a decrease in the activity of the antioxidant catalase. Lung sections of mice exposed to CeO2 NPs showed a dose-dependent infiltration of inflammatory cells consisting of macrophages and neutrophils. Similarly, the plasma levels of C-reactive protein and TNFα were significantly increased, whereas the activities of catalase and total antioxidant were significantly decreased. Interestingly, CeO2 NPs significantly and dose dependently induced a shortening of the thrombotic occlusion time in pial arterioles and venules. Moreover, the plasma concentrations of fibrinogen and plasminogen activator inhibitor-1 were significantly elevated by CeO2 NPs. The direct addition of CeO2 NPs (1, 5, or 25 µg/mL to mouse whole blood, collected from the inferior vena cava, in vitro neither caused significant platelet aggregation nor affected prothrombin time or partial

  7. Acute inflammatory reaction in rats after intratracheal instillation of material collected from a nylon flocking plant.

    Science.gov (United States)

    Porter, D W; Castranova, V; Robinson, V A; Hubbs, A F; Mercer, R R; Scabilloni, J; Goldsmith, T; Schwegler-Berry, D; Battelli, L; Washko, R; Burkhart, J; Piacitelli, C; Whitmer, M; Jones, W

    1999-05-14

    Several cases of interstitial lung disease have been diagnosed among workers at a nylon flock plant, but the etiologic agent for the disease outbreak was unknown. The results of a medical survey and industrial hygiene study indicated that the dust present in the plant may be responsible. Thus, airborne dust collected at the plant was examined for its inflammatory potential in rat lungs. The endpoints measured were: (1) breathing rates, (2) differential cell counts of bronchoalveolar lavage cells, (3) alveolar macrophage (AM) chemiluminescence, (4) albumin concentration and matrix metalloprotease activities in the acellular fluid from the initial bronchoalveolar lavage, and (5) pulmonary histopathology. In the first study, rats received a single dose of the airborne dust sample (10 mg/kg body weight) by intratracheal (IT) instillation. At 1 d post-IT, all inflammatory endpoints were significantly increased versus controls, but by 29 d post-IT they did not differ significantly from controls. Histopathology demonstrated mild to moderate, multifocal, suppurative pneumonia, usually centered around bronchioles, at 1 d post-IT. At 29 d post-IT, pulmonary inflammation was minimal to mild and characterized by alveolar histocytosis usually restricted to the immediate area of retained bire-fringent fibers. In subsequent experiments, airborne dust was extracted with water and the dust (washed airborne dust) and water extract (soluble fraction) were separated by centrifugation for further study. Nylon tow dust was prepared in the laboratory by milling uncut nylon strands (called tow) that had not been treated with the finish or dyes that are commonly used in the flock plants. Rats were administered a single dose of a dust sample (10 mg/kg body weight) or the soluble fraction (1.3 ml/kg body weight) by IT administration and the same endpoints were measured at 1 d post-IT. The dust samples caused significant increases in all of the inflammatory endpoints; however, the soluble

  8. Intratracheal Instillation of High Dose Adenoviral Vectors Is Sufficient to Induce Lung Injury and Fibrosis in Mice

    Science.gov (United States)

    Zhou, Qiyuan; Chen, Tianji; Bozkanat, Melike; Ibe, Joyce Christina F.; Christman, John W.; Raj, J. Usha; Zhou, Guofei

    2014-01-01

    Rationale Replication deficient adenoviruses (Ad) vectors are common tools in gene therapy. Since Ad vectors are known to activate innate and adaptive immunity, we investigated whether intratracheal administration of Ad vectors alone is sufficient to induce lung injury and pulmonary fibrosis. Methods We instilled Ad viruses ranging from 107 to 1.625×109 ifu/mouse as well as the same volume of PBS and bleomycin. 14 and 21 days after administration, we collected bronchoalveolar lavage fluid (BALF) and mouse lung tissues. We measured the protein concentration, total and differential cell counts, and TGF-β1 production, performed Trichrome staining and Sircol assay, determined gene and protein levels of profibrotic cytokines, MMPs, and Wnt signaling proteins, and conducted TUNEL staining and co-immunofluorescence for GFP and α-SMA staining. Results Instillation of high dose Ad vectors (1.625×109 ifu/mouse) into mouse lungs induced high levels of protein content, inflammatory cells, and TGF-β1 in BALF, comparable to those in bleomycin-instilled lungs. The collagen content and mRNA levels of Col1a1, Col1a2, PCNA, and α-SMA were also increased in the lungs. Instillation of both bleomycin and Ad vectors increased expression levels of TNFα and IL-1β but not IL-10. Instillation of bleomycin but not Ad increased the expression of IL-1α, IL-13 and IL-16. Treatment with bleomycin or Ad vectors increased expression levels of integrin α1, α5, and αv, MMP9, whereas treatment with bleomycin but not Ad vectors induced MMP2 expression levels. Both bleomycin and Ad vectors induced mRNA levels of Wnt2, 2b, 5b, and Lrp6. Intratracheal instillation of Ad viruses also induced DNA damages and Ad viral infection-mediated fibrosis is not limited to the infection sites. Conclusions Our results suggest that administration of Ad vectors induces an inflammatory response, lung injury, and pulmonary fibrosis in a dose dependent manner. PMID:25551570

  9. Cardiovascular and inflammatory effects of intratracheally instilled ambient dust from Augsburg, Germany, in spontaneously hypertensive rats (SHRs

    Directory of Open Access Journals (Sweden)

    Peters Annette

    2010-09-01

    Full Text Available Abstract Rationale Several epidemiological studies associated exposure to increased levels of particulate matter in Augsburg, Germany with cardiovascular mortality and morbidity. To elucidate the mechanisms of cardiovascular impairments we investigated the cardiopulmonary responses in spontaneously hypertensive rats (SHR, a model for human cardiovascular diseases, following intratracheal instillation of dust samples from Augsburg. Methods 250 μg, 500 μg and 1000 μg of fine ambient particles (aerodynamic diameter 2.5-AB collected from an urban background site in Augsburg during September and October 2006 (PM2.5 18.2 μg/m3, 10,802 particles/cm3 were instilled in 12 months old SHRs to assess the inflammatory response in bronchoalveolar lavage fluid (BALF, blood, lung and heart tissues 1 and 3 days post instillation. Radio-telemetric analysis was performed to investigate the cardiovascular responses following instillation of particles at the highest dosage based on the inflammatory response observed. Results Exposure to 1000 μg of PM2.5-AB was associated with a delayed increase in delta mean blood pressure (ΔmBP during 2nd-4th day after instillation (10.0 ± 4.0 vs. -3.9 ± 2.6 mmHg and reduced heart rate (HR on the 3rd day post instillation (325.1 ± 8.8 vs. 348.9 ± 12.5 bpm. BALF cell differential and inflammatory markers (osteopontin, interleukin-6, C-reactive protein, and macrophage inflammatory protein-2 from pulmonary and systemic level were significantly induced, mostly in a dose-dependent way. Protein analysis of various markers indicate that PM2.5-AB instillation results in an activation of endothelin system (endothelin1, renin-angiotensin system (angiotensin converting enzyme and also coagulation system (tissue factor, plasminogen activator inhibitor-1 in pulmonary and cardiac tissues during the same time period when alternation in ΔmBP and HR have been detected. Conclusions Our data suggests that high concentrations of PM2.5-AB

  10. Oxidative DNA damage in vitamin C-supplemented guinea pigs after intratracheal instillation of diesel exhaust particles

    DEFF Research Database (Denmark)

    Moller, P.; Daneshvar, B.; Loft, S.

    2003-01-01

    The health effects of diesel exhaust particles (DEP) are thought to involve oxidative damage. We have investigated the effect of intratracheal DEP instillation to guinea pigs in three groups of 12 animals each given 0, 0.7, or 2.1 mg. Five days later guinea pigs exposed to DEP had increased levels...... of oxidized amino acids (gamma-glutamyl semialdehyde), DNA strand breaks, and 7-hydro-8-oxo-2'-deoxyguanosine (8-oxodG) in the lung. Bulky DNA ad- ducts were not significantly elevated in the lung. The antioxidant enzyme activity of glutathione reductase was increased in the lung of DEP-exposed guinea pigs....... The concentrations of ascorbate in liver, lung, and plasma were unaltered by the DEP exposure. The results indicate that in guinea pigs DEP causes oxidative DNA damage rather than bulky DNA adducts in the lung. Guinea pigs, which are similar to humans with respect to vitamin C metabolism, may serve as a new model...

  11. Oxidative DNA damage in vitamin C-supplemented guinea pigs after intratracheal instillation of diesel exhaust particles

    DEFF Research Database (Denmark)

    Moller, P.; Daneshvar, B.; Loft, S.

    2003-01-01

    of oxidized amino acids (gamma-glutamyl semialdehyde), DNA strand breaks, and 7-hydro-8-oxo-2'-deoxyguanosine (8-oxodG) in the lung. Bulky DNA ad- ducts were not significantly elevated in the lung. The antioxidant enzyme activity of glutathione reductase was increased in the lung of DEP-exposed guinea pigs......, whereas glutathione peroxidase and superoxide dismutase enzyme activities were unaltered. There was no difference in DNA strand breaks in lymphocytes or urinary excretion of 8-oxodG at the two doses tested. Protein oxidations in plasma and in erythrocytes were not altered by DEP exposure......The health effects of diesel exhaust particles (DEP) are thought to involve oxidative damage. We have investigated the effect of intratracheal DEP instillation to guinea pigs in three groups of 12 animals each given 0, 0.7, or 2.1 mg. Five days later guinea pigs exposed to DEP had increased levels...

  12. Intratracheally instilled titanium dioxide nanoparticles translocate to heart and liver and activate complement cascade in the heart of C57BL/6 mice

    DEFF Research Database (Denmark)

    Husain, Mainul; Wu, Dongmei; Saber, Anne T.

    2015-01-01

    translocation from the lungs. Adult female C57BL/6 mice were exposed via intratracheal instillation to 18 or 162 mu g of industrially relevant titanium dioxide nanoparticles (nano-TiO2) alongside vehicle controls. Using the nano-scale hyperspectral microscope, translocation to heart and liver was confirmed...

  13. Acute and subchronic airway inflammation after intratracheal instillation of quartz and titanium dioxide agglomerates in mice

    DEFF Research Database (Denmark)

    Roursgaard, Martin; Jensen, Keld A; Poulsen, Steen Seier

    2011-01-01

    compounds were the two micro-size reference quartzes, SRM1878a and DQ12, a micro- and nano-size rutile titanium dioxide (TiO2), a nano-size anatase, and an amorphous TiO2. Particles were administered by a single i.t. instillation in mice at a fixed dose of 5, 50, and 500 micrograms, respectively...

  14. Size effect of intratracheally instilled particles on pulmonary inflammation and vascular thrombosis.

    Science.gov (United States)

    Nemmar, Abderrahim; Hoylaerts, Marc F; Hoet, Peter H M; Vermylen, Jozef; Nemery, Benoit

    2003-01-01

    Particulate air pollution is associated with cardiorespiratory effects and ultrafine particles (UFPs, diameter particles on bronchoalveolar lavage (BAL) indices and on peripheral thrombosis in hamster. The latter was assessed by measuring the extent of photochemically induced thrombosis in a femoral vein via transillumination. Unmodified and negative UFPs did not modify thrombosis and BAL indices. Positive UFPs increased thrombosis at 500 microg per animal (+ 341 +/- 96%) and at 50 microg per animal (+ 533 +/- 122%), but not at 5 microg per animal. Neutrophils, lactate dehydrogenase, and histamine were increased in BAL at all these doses but protein concentration was increased only at 500 microg per animal. Positive 400-nm particles (500 microg per animal) did not affect thrombosis, although they led to a neutrophil influx and an increase in BAL proteins and histamine. Using the Platelet Function Analyser (PFA-100), the platelets of hamsters were activated by the in vitro addition of positive UFPs and 400-nm particles to blood. We conclude that intratracheally administered positive ultrafine and 400-nm particles induce pulmonary inflammation within 1 h. Positive UFPs, but not the 400-nm particles enhance thrombosis. Hence, particle-induced lung inflammation and thrombogenesis can be partially uncoupled. Copyright 2003 Elsevier Science (USA)

  15. Injurious mechanical ventilation causes kidney apoptosis and dysfunction during sepsis but not after intra-tracheal acid instillation: an experimental study.

    Science.gov (United States)

    Kuiper, Jan Willem; Groeneveld, A B Johan; Haitsma, Jack J; Smeding, Lonneke; Begieneman, Mark P V; Jothy, Serge; Vaschetto, Rosanna; Plötz, Frans B

    2014-07-29

    Intratracheal aspiration and sepsis are leading causes of acute lung injury that frequently necessitate mechanical ventilation (MV), which may aggravate lung injury thereby potentially increasing the risk of acute kidney injury (AKI). We compared the effects of ventilation strategies and underlying conditions on the development of AKI. Spraque Dawley rats were challenged by intratracheal acid instillation or 24 h of abdominal sepsis, followed by MV with a low tidal volume (LVT) and 5 cm H2O positive end-expiratory pressure (PEEP) or a high tidal volume (HVT) and no PEEP, which is known to cause more lung injury after acid instillation than in sepsis. Rats were ventilated for 4 hrs and kidney function and plasma mediator levels were measured. Kidney injury was assessed by microscopy; apoptosis was quantified by TUNEL staining. During sepsis, but not after acid instillation, MV with HVT caused more renal apoptosis than MV with LVT. Increased plasma active plasminogen activator inhibitor-1 correlated to kidney apoptosis in the cortex and medulla. Increased apoptosis after HVT ventilation during sepsis was associated with a 40% decrease in creatinine clearance. AKI is more likely to develop after MV induced lung injury during an indirect (as in sepsis) than after a direct (as after intra-tracheal instillation) insult to the lungs, since it induces kidney apoptosis during sepsis but not after acid instillation, opposite to the lung injury it caused. Our findings thus suggest using protective ventilatory strategies in human sepsis, even in the absence of overt lung injury, to protect the kidney.

  16. Comparison of the Pulmonary Oxidative Stress Caused by Intratracheal Instillation and Inhalation of NiO Nanoparticles when Equivalent Amounts of NiO Are Retained in the Lung

    Directory of Open Access Journals (Sweden)

    Masanori Horie

    2016-01-01

    Full Text Available NiO nanoparticles were administered to rat lungs via intratracheal instillation or inhalation. During pulmonary toxicity caused by NiO nanoparticles, the induction of oxidative stress is a major factor. Both intratracheal instillation and inhalation of NiO nanoparticles induced pulmonary oxidative stress. The oxidative stress response protein, heme oxygenase-1 (HO-1, was induced by the administration of NiO nanoparticles at both the protein and gene expression level. Additionally, certain oxidative-stress markers in the lung, such as 8-iso-prostaglandin F2α, thioredoxin, and inducible nitric oxide synthase were increased. Furthermore, the concentration of myeloperoxidase (MPO in the lung was also increased by the administration of NiO nanoparticles. When the amount of NiO in the lung is similar, the responses against pulmonary oxidative stress of intratracheal instillation and inhalation are also similar. However, the state of pulmonary oxidative stress in the early phase was different between intratracheal instillation and inhalation, even if the amount of NiO in the lung was similar. Inhalation causes milder oxidative stress than that caused by intratracheal instillation. On evaluation of the nanoparticle-induced pulmonary oxidative stress in the early phase, we should understand the different states of oxidative stress induced by intratracheal instillation and inhalation.

  17. Pulmonary toxicity of simulated lunar and Martian dusts in mice: II. Biomarkers of acute responses after intratracheal instillation

    Science.gov (United States)

    Lam, Chiu-Wing; James, John T.; Latch, Judith N.; Hamilton, Raymond F Jr; Holian, Andrij

    2002-01-01

    Volcanic ashes from Arizona and Hawaii, with chemical and mineral properties similar to those of lunar and Martian soils, respectively, are used by the National Aeronautics and Space Administration (NASA) to simulate lunar and Martian environments for instrument tests. NASA needs toxicity data on these volcanic soils to assess health risks from potential exposures of workers in facilities where these soil simulants are used. In this study we investigated the acute effects of lunar soil simulant (LSS) and Martian soil simulant (MSS), as a complement to a histopathological study assessing their subchronic effects (Lam et al., 2002). Fine dust of LSS, MSS, TiO(2), or quartz suspended in saline was intratracheally instilled into C57Bl/6J mice (4/group) in single doses of 0.1 mg/mouse or 1 mg/mouse. The mice were euthanized 4 or 24 h after the dust treatment, and bronchoalveolar lavage fluid (BALF) was obtained. Statistically significant lower cell viability and higher total protein concentration in the BALF were seen only in mice treated with the high dose of quartz for 4 h and with the high dose of MSS or quartz for 24 h, compared to mice treated only with saline. A significant increase in the percentage of neutrophils was not observed with any dust-treated group at 4 h after the instillation, but was observed after 24 h in all the dust-treated groups. This observation indicates that these dusts were not acutely toxic and the effects were gradual; it took some time for neutrophils to be recruited into and accumulate significantly in the lung. A statistically significant increase in apoptosis of lavaged macrophages from mice 4 h after treatment was found only in the high-dose silica group. The overall results of this study on the acute effects of these dusts in the lung indicate that LSS is slightly more toxic than TiO(2), and that MSS is comparable to quartz. These results were consistent with the subchronic histopathological findings in that the order of severity of

  18. Repeated intratracheal instillation of PM10 induces lipid reshaping in lung parenchyma and in extra-pulmonary tissues.

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    Angela Maria Rizzo

    Full Text Available Adverse health effects of air pollution attributed mainly to airborne particulate matter have been well documented in the last couple of decades. Short term exposure, referring to a few hours exposure, to high ambient PM10 concentration is linked to increased hospitalization rates for cardiovascular events, typically 24 h after air pollution peaks. Particulate matter exposure is related to pulmonary and cardiovascular diseases, with increased oxidative stress and inflammatory status. Previously, we have demonstrated that repeated intratracheal instillation of PM10sum in BALB/c mice leads to respiratory tract inflammation, creating in lung a condition which could potentially evolve in a systemic toxic reaction. Additionally, plasma membrane and tissue lipids are easily affected by oxidative stress and directly correlated with inflammatory products. With this aim, in the present investigation using the same model, we analyzed the toxic potential of PM10sum exposure on lipid plasma membrane composition, lipid peroxidation and the mechanisms of cells protection in multiple organs such as lung, heart, liver and brain. Obtained results indicated that PM10 exposure led to lung lipid reshaping, in particular phospholipid and cholesterol content increases; concomitantly, the generation of oxidative stress caused lipid peroxidation. In liver we found significant changes in lipid content, mainly due to an increase of phosphatidylcholine, and in total fatty acid composition with a more pronounced level of docosahexaenoic acid; these changes were statistically correlated to lung molecular markers. Heart and brain were similarly affected; heart was significantly enriched in triglycerides in half of the PM10sum treated mice. These results demonstrated a direct involvement of PM10sum in affecting lipid metabolism and oxidative stress in peripheral tissues that might be related to the serious systemic air-pollution effects on human health.

  19. Pulmonary toxicity of single-wall carbon nanotubes in mice 7 and 90 days after intratracheal instillation

    Science.gov (United States)

    Lam, Chiu-Wing; James, John T.; McCluskey, Richard; Hunter, Robert L.

    2004-01-01

    Nanomaterials are part of an industrial revolution to develop lightweight but strong materials for a variety of purposes. Single-wall carbon nanotubes are an important member of this class of materials. They structurally resemble rolled-up graphite sheets, usually with one end capped; individually they are about 1 nm in diameter and several microns long, but they often pack tightly together to form rods or ropes of microscopic sizes. Carbon nanotubes possess unique electrical, mechanical, and thermal properties and have many potential applications in the electronics, computer, and aerospace industries. Unprocessed nanotubes are very light and could become airborne and potentially reach the lungs. Because the toxicity of nanotubes in the lung is not known, their pulmonary toxicity was investigated. The three products studied were made by different methods and contained different types and amounts of residual catalytic metals. Mice were intratracheally instilled with 0, 0.1, or 0.5 mg of carbon nanotubes, a carbon black negative control, or a quartz positive control and euthanized 7 d or 90 d after the single treatment for histopathological study of the lungs. All nanotube products induced dose-dependent epithelioid granulomas and, in some cases, interstitial inflammation in the animals of the 7-d groups. These lesions persisted and were more pronounced in the 90-d groups; the lungs of some animals also revealed peribronchial inflammation and necrosis that had extended into the alveolar septa. The lungs of mice treated with carbon black were normal, whereas those treated with high-dose quartz revealed mild to moderate inflammation. These results show that, for the test conditions described here and on an equal-weight basis, if carbon nanotubes reach the lungs, they are much more toxic than carbon black and can be more toxic than quartz, which is considered a serious occupational health hazard in chronic inhalation exposures.

  20. Effects of intratracheally instilled laser printer-emitted engineered nanoparticles in a mouse model: A case study of toxicological implications from nanomaterials released during consumer use

    Science.gov (United States)

    Pirela, Sandra V.; Lu, Xiaoyan; Miousse, Isabelle; Sisler, Jennifer D.; Qian, Yong; Guo, Nancy; Koturbash, Igor; Castranova, Vincent; Thomas, Treye; Godleski, John; Demokritou, Philip

    2016-01-01

    Incorporation of engineered nanomaterials (ENMs) into toners used in laser printers has led to countless quality and performance improvements. However, the release of ENMs during printing (consumer use) has raised concerns about their potential adverse health effects. The aim of this study was to use “real world” printer-emitted particles (PEPs), rather than raw toner powder, and assess the pulmonary responses following exposure by intratracheal instillation. Nine-week old male Balb/c mice were exposed to various doses of PEPs (0.5, 2.5 and 5 mg/kg body weight) by intratracheal instillation. These exposure doses are comparable to real world human inhalation exposures ranging from 13.7 to 141.9 h of printing. Toxicological parameters reflecting distinct mechanisms of action were evaluated, including lung membrane integrity, inflammation and regulation of DNA methylation patterns. Results from this in vivo toxicological analysis showed that while intratracheal instillation of PEPs caused no changes in the lung membrane integrity, there was a pulmonary immune response, indicated by an elevation in neutrophil and macrophage percentage over the vehicle control and low dose PEPs groups. Additionally, exposure to PEPs upregulated expression of the Ccl5 (Rantes), Nos1 and Ucp2 genes in the murine lung tissue and modified components of the DNA methylation machinery (Dnmt3a) and expression of transposable element (TE) LINE-1 compared to the control group. These genes are involved in both the repair process from oxidative damage and the initiation of immune responses to foreign pathogens. The results are in agreement with findings from previous in vitro cellular studies and suggest that PEPs may cause immune responses in addition to modifications in gene expression in the murine lung at doses that can be comparable to real world exposure scenarios, thereby raising concerns of deleterious health effects. PMID:26989787

  1. Effects of intratracheally instilled laser printer-emitted engineered nanoparticles in a mouse model: A case study of toxicological implications from nanomaterials released during consumer use.

    Science.gov (United States)

    Pirela, Sandra V; Lu, Xiaoyan; Miousse, Isabelle; Sisler, Jennifer D; Qian, Yong; Guo, Nancy; Koturbash, Igor; Castranova, Vincent; Thomas, Treye; Godleski, John; Demokritou, Philip

    2016-01-01

    Incorporation of engineered nanomaterials (ENMs) into toners used in laser printers has led to countless quality and performance improvements. However, the release of ENMs during printing (consumer use) has raised concerns about their potential adverse health effects. The aim of this study was to use "real world" printer-emitted particles (PEPs), rather than raw toner powder, and assess the pulmonary responses following exposure by intratracheal instillation. Nine-week old male Balb/c mice were exposed to various doses of PEPs (0.5, 2.5 and 5 mg/kg body weight) by intratracheal instillation. These exposure doses are comparable to real world human inhalation exposures ranging from 13.7 to 141.9 h of printing. Toxicological parameters reflecting distinct mechanisms of action were evaluated, including lung membrane integrity, inflammation and regulation of DNA methylation patterns. Results from this in vivo toxicological analysis showed that while intratracheal instillation of PEPs caused no changes in the lung membrane integrity, there was a pulmonary immune response, indicated by an elevation in neutrophil and macrophage percentage over the vehicle control and low dose PEPs groups. Additionally, exposure to PEPs upregulated expression of the Ccl5 ( Rantes ), Nos1 and Ucp2 genes in the murine lung tissue and modified components of the DNA methylation machinery ( Dnmt3a ) and expression of transposable element (TE) LINE-1 compared to the control group. These genes are involved in both the repair process from oxidative damage and the initiation of immune responses to foreign pathogens. The results are in agreement with findings from previous in vitro cellular studies and suggest that PEPs may cause immune responses in addition to modifications in gene expression in the murine lung at doses that can be comparable to real world exposure scenarios, thereby raising concerns of deleterious health effects.

  2. Comparative study of the toxic effects of gallium arsenide, indium arsenide and arsenic trioxide following intratracheal instillations to the lung of Syrian golden hamsters.

    Science.gov (United States)

    Tanaka, A; Hirata, M; Omura, M; Zhao, M; Makita, Y; Yamazaki, K; Inoue, N; Gotoh, K

    2000-01-01

    Toxic effects of gallium arsenide (GaAs), indium arsenide (InAs) and arsenic trioxide (As2O3) were studied in male Syrian golden hamsters. GaAs (7.7 mg/kg) and As2O3 (1.3 mg/kg) particles were instilled intratracheally twice a week a total of 16 times, while InAs (7.7 mg/kg) was instilled a total of 14 times. As a control, hamsters were treated with the vehicle, phosphate buffer solution. During the instillation period, the cumulative body weight gain of the InAs-, but not the GaAs- or As2O3-treated hamsters was suppressed significantly, when compared with the control group. Slight to severe inflammatory responses were observed in the lung for all treatment groups. The most severe inflammatory change, characterized by an accumulation of neutrophils and macrophages, exudation, thickness of the pleura and fibrotic proliferation was found in the InAs-treated hamsters. Extensive alveolar or bronchiolar cell hyperplasia with or without keratinizing squamous cell metaplasia was observed in almost all the InAs-treated hamsters. Furthermore, squamous cell metaplasia or squamous cell hyperplasia developed in some of the InAs-treated hamsters, but not in the GaAs- or As2O3-treated hamsters. Slight to mild lesions were found in the convoluted tubules of the kidney in both the GaAs and InAs groups. From the present study, the toxic potency of these particles was provisionally estimated to be in the following order: InAs > GaAs > As2O3, at the dosage level used in this study. Furthermore, there was evidence that InAs particles could induce pulmonary, renal or systemic toxicity, and as such, InAs particles may produce pulmonary precancerous change when instilled intratracheally into hamsters.

  3. Induction of biotransformation enzymes by the carcinogenic air-pollutant 3-nitrobenzanthrone in liver, kidney and lung, after intra-tracheal instillation in rats.

    Science.gov (United States)

    Mizerovská, Jana; Dračínská, Helena; Frei, Eva; Schmeiser, Heinz H; Arlt, Volker M; Stiborová, Marie

    2011-02-28

    3-Nitrobenzanthrone (3-NBA), a carcinogenic air pollutant, was investigated for its ability to induce cytochrome P450 (CYP) 1A1/2 and NAD(P)H:quinone oxidoreductase (NQO1) in liver, kidney and lung of rats treated by intra-tracheal instillation. The organs used were from a previous study performed to determine the persistence of 3-NBA-derived DNA adducts in target and non-target tissues (Bieler et al., Carcinogenesis 28 (2007) 1117-1121, [22]). NQO1 is the enzyme reducing 3-NBA to N-hydroxy-3-aminobenzanthrone (N-OH-3-ABA) and CYP1A enzymes oxidize a human metabolite of 3-NBA, 3-aminobenzanthrone (3-ABA), to yield the same reactive intermediate. 3-NBA and 3-ABA are both activated to species forming DNA adducts by cytosols and/or microsomes isolated from rat lung, the target organ for 3-NBA carcinogenicity, and from liver and kidney. Each compound generated the same five DNA adducts detectable by (32)P-postlabelling. When hepatic cytosols from rats treated with 0.2 or 2mg/kg body weight of 3-NBA were incubated with 3-NBA, DNA adduct formation was 3.2- and 8.6-fold higher, respectively, than in incubations with cytosols from control animals. Likewise, cytosols isolated from lungs and kidneys of rats exposed to 3-NBA more efficiently activated 3-NBA than those of control rats. This increase corresponded to an increase in protein levels and enzymatic activities of NQO1. Incubations of hepatic, pulmonary or renal microsomes of 3-NBA-treated rats with 3-ABA led to an 9.6-fold increase in DNA-adduct formation relative to controls. The highest induction in DNA-adduct levels was found in lung. The stimulation of DNA-adduct formation correlated with expression of CYP1A1/2 induced by the intra-tracheal instillation of 3-NBA. The results demonstrate that 3-NBA induces NQO1 and CYP1A1/2 in livers, lungs and kidneys of rats after intra-tracheal instillation, thereby enhancing its own genotoxic and carcinogenic potential. Copyright © 2010 Elsevier B.V. All rights reserved.

  4. Oxidative stress, inflammation, and DNA damage in rats after intratracheal instillation or oral exposure to ambient air and wood smoke particulate matter

    DEFF Research Database (Denmark)

    Danielsen, Pernille Høgh; Loft, Steffen; Jacobsen, Nicklas Raun

    2010-01-01

    or intratracheal exposure in terms of oxidative stress, inflammation, genotoxicity, and DNA repair after 24 h in liver and lung tissue of rats. Rats were exposed to WSPM from high or low oxygen combustion and ambient PM collected in areas with and without many operating wood stoves or carbon black (CB) at the dose...... expression of proinflammatory cytokines, heme oxygenase-1, and oxoguanine DNA glycosylase 1 was observed in the liver following intragastric exposure and in the lung following instillation in particular of LOWS. Exposure to LOWS also increased the proportion of neutrophils in BAL fluid. These results...... indicate that WSPM and CB exert the strongest effect in terms of oxidative stress-induced response, inflammation, and genotoxicity in the organ closest to the port of entry....

  5. Rat strain differences in levels and effects of chronic inflammation due to intratracheal instillation of quartz on lung tumorigenesis induced by DHPN.

    Science.gov (United States)

    Nakano, Yuko; Yokohira, Masanao; Hashimoto, Nozomi; Yamakawa, Keiko; Kishi, Sosuke; Ninomiya, Fumiko; Kanie, Shohei; Saoo, Kousuke; Imaida, Katsumi

    2014-10-01

    Chronic inflammatory effects of single intratracheal instillation (i.t.) of quartz on rat lung tumorigenesis were examined using 4 different animal models. At first, in order to determine an appropriate dose of quartz i.t. to promote lung tumorigenesis, F344 male rats were administrated single 0, 0.5, 1, 2 or 4 mg quartz/rat after initiation by N-bis(2-hydroxypropyl) nitrosamine (DHPN). Further studies were performed to examine strain differences of the effects of chronic inflammation caused by quartz i.t. in 3 strains of rat, i.e. F344, Wistar-Hannover and SD. Each was instilled with 2mg quartz/rat after DHPN administration and sacrificed in week 24. In addition, strain differences in generation of inflammation were determined at days 1 and 28. Finally, for determination of long-term effects period, F344 and Wistar-Hannover rats were similarly treated, but the experiment was terminated at week 52. In F344 rats, the tumor areas in DHPN treated groups showed a tendency to increase along with the dose of quartz. F344 rats demonstrated the highest and Wistar-Hannover rats the lowest sensitivity to quartz in acute and chronic phases in the 3 strains. In 52 week, in F344 rats, the multiplicity of tumors and the serum concentration of IL-6 in the group treated with DHPN and quartz were significantly increased. The present experiments indicated that chronic inflammation due to quartz instillation exerted promoting effects on lung carcinogenesis in F344, SD and Wistar-Hannover rats. The strain differences in tumor promotion appeared to correlate with inflammatory reactions to quartz and increase of IL-6. Copyright © 2014 Elsevier GmbH. All rights reserved.

  6. Biological availability of lead in a paint aerosol. 2. Absorption, distribution and excretion of intratracheally instilled lead paint particles in the rat.

    Science.gov (United States)

    Eaton, D L; Kalman, D; Garvey, D; Morgan, M; Omenn, G S

    1984-09-01

    Four groups of rats received by intratracheal instillation (1) a lead chromate paint particulate suspension, (2) lead tetraoxide suspension, (3) lead acetate solution, or (4) saline. Lead-dosed animals received an equivalent dose of 1 mg lead/kg body weight. Distribution of lead was monitored through assays of urine, feces, and tissues (lung, bone, muscle kidney, liver) obtained at post-mortem 5 weeks after exposure. Delta-aminolevulinic acid dehydratase (ALA-D) activity was measured to determine the effect of lead on heme biosynthesis. The vast majority of the dosed lead in the paint matrix remained in the lung. In contrast, in the lead acetate-dosed animals, little remained in the lung, but significant elevations were found in bone and kidney. Blood ADA-D was significantly depressed in the lead acetate-treated animals, but was not significantly different from control animals in the animals dosed with lead paint or lead tetraoxide. These findings suggest that lead chromate in an alkyd resin paint matrix is poorly absorbed from the lung compared with lead acetate and lead tetraoxide.

  7. In vitro the differences of inflammatory and oxidative reactions due to sulfur mustard induced acute pulmonary injury underlying intraperitoneal injection and intratracheal instillation in rats.

    Science.gov (United States)

    Yu, Dan; Bei, Yuan-Yuan; Li, Yuan; Han, Wei; Zhong, Yu-Xu; Liu, Fei; Zhao, Yu-Ling; Zhu, Xiao-Ji; Zhao, Jian

    2017-06-01

    This study was to investigate the differences of inflammatory reaction and oxidative stress due to sulfur mustard (SM)-induced acute pulmonary injury via two ways in rats. In intraperitoneal and tracheal SM groups, injected intraperitoneally and instilled intratracheally with 0.1mL diluted SM (0.96 LD 50 =8mg/kg) and SM (0.98 LD 50 =2mg/kg) were administered in rats. In bronchoalveolar lavage fluid, serum, and alveolar septum, lactate dehydrogenase, glutathione peroxidase, tumor necrosis factor-α, interleukin-1β, interleukin-6, C-reactive protein, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, l-selectin, r-glutamyl transpeptidase, thiobarbituric acid reactive substances levels as well as the expression of CD4, CD20, CD68, 8-hydroxy deoxyguanosine, nuclear factor-E2-related factor 2, and heme oxygenase-1 measured by ELISA, immune scatter turbidimetry and immunohistochemical method in the intraperitoneal SM group were increased at each time-point compared with the tracheal SM groups, respectively. These data demonstrated an increased inflammatory reaction and oxidative stress indices in rat via intraperitoneal injection under similar SM LD 50 doses. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Biological effects of nano-nickel in rat lungs after administration by inhalation and by intratracheal instillation

    International Nuclear Information System (INIS)

    Ogami, A; Morimoto, Y; Murakami, M; Myojo, T; Oyabu, T; Tanaka, I

    2009-01-01

    We examined the biological effects of the nickel oxide (NiO) nanoparticles by inhalation and instillation study. Wistar male rats were exposed to NiO nanoparticles (nNiOs) for 4 weeks (6 hrs/day). The nNiOs was black-colored NiO (99.8%) and average particle size (APS) was 20 nm. The geometric mean diameter of the particles in the chamber and the daily average exposure concentration were 139 ± 12 nm and 1.0 ± 0.5 x 105 particles/cc, respectively. The deposited amount of nNiOs in the rat lungs at 4 days after the inhalation exposure ended was 29 ± 4 μg. Although nNiOs exposure group showed temporal significant increase in the number of total cells in brochoalveolar lavage fluid (BALF) at 4 days after the exposure end, the difference were not seen at one month after an exposure end compared with control group. The histopathological change was not severe just after the inhalation nor throughout the observation time. Elemental mappings of nickel showed that nickel particles were located in agglomeration at the pulmonary macrophages.

  9. In vivo study with quartz-containing ceramic dusts: Inflammatory effects of two factory samples in lungs after intratracheal instillation in a 28-day study with rats

    Energy Technology Data Exchange (ETDEWEB)

    Creutzenberg, O; Ziemann, C; Hansen, T; Ernst, H [Fraunhofer Institute of Toxicology and Experimental Medicine, Hannover (Germany); Jackson, P; Cartlidge, D [CERAM Research Ltd., Stoke-on-Trent (United Kingdom); Brown, R, E-mail: otto.creutzenberg@item.fraunhofer.d [TOXSERVICES, Stretton (United Kingdom)

    2009-02-01

    As various quartz polymorphs react differently in lungs, a differentiation of effects is needed while setting occupational exposure levels. The objective of this European Collective Research Project SILICERAM was to characterize differences in biological activity of four quartz species, i.) 2 quartz-containing materials collected at typical ceramic manufacturing sites (Tableware granulate, TG and Tableware cast, TC) versus ii.) a designed ceramic dust sample (Contrived Sample, CS) and iii.) ground quartz DQ12 (well-characterised standard quartz (Positive Control, PC) and TiO{sub 2} (negative control). TG and TC had been selected as the most promising two candidates based on a preceding in vitro screening of 5 factory samples. Total doses of 5 mg per rat of the TG and TC, 1.1 mg of the CS and 0.33 mg of the PC corresponding to 0.29, 0.16, 0.29 and 0.29 mg quartz per rat, respectively, were administered to rats by intratracheal instillation. After 3 days, bronchoalveolar lavagate (BAL) analysis resulted in polymorphonuclear neutrophil (PMN) levels of 15%, 25%, 0.6% and 25% in the TG, TC, CS and PC groups, respectively. At 28 days, the values were 29%, 20%, 7% and 45%. Histopathologically, the TG and TC groups showed very slight to slight effects, the PC group, however, stronger effects after the same period. In conclusion, the following ranking was found: PC > TG > TC > CS > TiO{sub 2} > Vehicle Control. Thus, a clear differentiation of effects for TG and TC, CS and PC was found. From a regulatory point of view, the substance-specific toxic potentials of TG and TC may need to be considered when devising occupational exposure limits.

  10. Carbon black nanoparticles induce biphasic gene expression changes associated with inflammatory responses in the lungs of C57BL/6 mice following a single intratracheal instillation

    DEFF Research Database (Denmark)

    Husain, Mainul; Kyjovska, Zdenka O.; Bourdon-Lacombe, Julie

    2015-01-01

    instilled with 162μg CBNPs alongside vehicle controls. Lung tissues were examined 3h, and 1, 2, 3, 4, 5, 14, and 42days (d) post-exposure. Global gene expression and pulmonary inflammation were assessed. DNA damage was evaluated in bronchoalveolar lavage (BAL) cells and lung tissue using the comet assay....... Increased neutrophil influx was observed at all time-points. DNA strand breaks were increased in BAL cells 3h post-exposure, and in lung tissues 2-5d post-exposure. Approximately 2600 genes were differentially expressed (±1.5 fold; p≤0.05) across all time-points in the lungs of exposed mice. Altered...... transcript levels were associated with immune-inflammatory response and acute phase response pathways, consistent with the BAL profiles and expression changes found in common respiratory infectious diseases. Genes involved in DNA repair, apoptosis, cell cycle regulation, and muscle contraction were also...

  11. Evaluation of the role of oxidative stress, inflammation and apoptosis in the pulmonary and the hepatic toxicity induced by cerium oxide nanoparticles following intratracheal instillation in male Sprague-Dawley rats

    Science.gov (United States)

    Nalabotu, Siva Krishna

    The field of nanotechnology is rapidly progressing with potential applications in the automobile, healthcare, electronics, cosmetics, textiles, information technology, and environmental sectors. Nanomaterials are engineered structures with at least one dimension of 100 nanometers or less. With increased applications of nanotechnology, there are increased chances of exposure to manufactured nanomaterials. Recent reports on the toxicity of engineered nanomaterials have given scientific and regulatory agencies concerns over the safety of nanomaterials. Specifically, the Organization for Economic Co-operation and Development (OECD) has identified fourteen high priority nanomaterials for study. Cerium oxide (CeO2) nanoparticles are one among the high priority group. Recent data suggest that CeO2 nanoparticles may be toxic to lung cell lines in vitro and lung tissues in vivo. Other work has proposed that oxidative stress may play an important role in the toxicity; however, the exact mechanism of the toxicity, has to our knowledge, not been investigated. Similarly, it is not clear whether CeO2 nanoparticles exhibit systemic toxicity. Here, we investigate whether pulmonary exposure to CeO2 nanoparticles is associated with oxidative stress, inflammation and apoptosis in the lungs and liver of adult male Sprague-Dawley rats. Our data suggest that the intratracheal instillation of CeO2 nanoparticles can cause an increased lung weight to body weight ratio. Changes in lung weights were associated with the accumulation of cerium in the lungs, elevations in serum inflammatory markers, an increased Bax to Bcl-2 ratio, elevated caspase-3 protein levels, increased phosphorylation of p38-MAPK and diminished phosphorylation of ERK1/2-MAPK. Our findings from the study evaluating the possible translocation of CeO2 nanoparticles from the lungs to the liver suggest that CeO 2 nanoparticle exposure was associated with increased liver ceria levels, elevations in serum alanine transaminase

  12. Pulmonary instillation of low doses of titanium dioxide nanoparticles in mice leads to particle retention and gene expression changes in the absence of inflammation

    DEFF Research Database (Denmark)

    Husain, Mainul; Saber, Anne Thoustrup; Guo, Charles

    2013-01-01

    We investigated gene expression, protein synthesis, and particle retention in mouse lungs following intratracheal instillation of varying doses of nano-sized titanium dioxide (nano-TiO2). Female C57BL/6 mice were exposed to rutile nano-TiO2 via single intratracheal instillations of 18, 54, and 162...

  13. Intrapulmonary perfluorooctyl bromide instillation in fetal rabbits.

    Science.gov (United States)

    Muensterer, Oliver J; Klis, Verena J; Till, Holger; Bergmann, Florian; Metzger, Roman; Simbruner, Georg

    2005-07-01

    Instilling perfluorooctyl bromide (PFOB) into the fetal lung may lead to alveolar distension. The aim of the study was to evaluate the safety of PFOB instillation into fetal lungs and to determine the radiographic distribution and tissue concentration of PFOB in New Zealand white rabbits. Sibling fetuses of pregnant (day 27) New Zealand white rabbits were randomized to intratracheal instillation of 1 mL PFOB with tracheal ligation, instillation without ligation, and unmanipulated controls. The maternal animals were killed directly after instillation, at 3 or 6 hours (n = 10 each). For each study cohort, we determined fetal lung/body weight (FLBW) ratios, the radiographic distribution of PFOB, as well as pulmonary PFOB and water content by tissue distillation. PFOB concentrations in maternal and fetal tissues were assessed by gas chromatography. The relative amount of fetal lung PFOB recovered by fractional distillation was highest in ligated (25%) and lower in unligated lungs (9%). Extrapulmonary PFOB was found in the fetal brain (2.0 +/- 0.7 ppm), but not in any other fetal or maternal tissues. Mean FLBW ratios were highest in ligated fetuses, followed by unligated fetuses and controls. PFOB partially displaced fetal lung water. PFOB was visible in the lungs of all treated fetuses. Fetal survival between manipulated and unmanipulated fetuses did not differ. After prenatal intrapulmonary instillation, some PFOB remains in the lung, even if the trachea is not ligated, and may exert distending pressure on the alveoli.

  14. Exposure of pregnant mice to carbon black by intratracheal instillation

    DEFF Research Database (Denmark)

    Jackson, Petra; Hougaard, Karin S.; Vogel, Ulla

    2011-01-01

    Exposure to nanomaterials (NM) during sensitive developmental stages may predispose organisms to diseases later in life. However, direct translocation of NM from mother to fetus through the placenta is limited. The present study tests the hypothesis that pulmonary exposure to NM and NM-induced re......Exposure to nanomaterials (NM) during sensitive developmental stages may predispose organisms to diseases later in life. However, direct translocation of NM from mother to fetus through the placenta is limited. The present study tests the hypothesis that pulmonary exposure to NM and NM...

  15. Pulmonary exposure to carbon black by inhalation or instillation in pregnant mice: Effects on liver DNA strand breaks in dams and offspring

    DEFF Research Database (Denmark)

    Jackson, Petra; Hougaard, Karin Sørig; Boisen, Anne Mette Zenner

    2011-01-01

    cells and liver, and in offspring liver. Persistent lung inflammation was observed in exposed mothers. Inhalation exposure induced more DNA strand breaks in the liver of mothers and their offspring, whereas intratracheal instillation did not. Neither inhalation nor instillation affected gestation...... and lactation. Maternal inhalation exposure to Printex 90-induced liver DNA damage in the mothers and the in utero exposed offspring....

  16. Protective effect of heme oxygenase-1 on lung injury induced by erythrocyte instillation in rats.

    Science.gov (United States)

    Pang, Qing-Feng; Zhou, Qiao-Mei; Zeng, Si; Dou, Li-Dong; Ji, Yong; Zeng, Yin-Ming

    2008-09-05

    Intratracheal instillation of blood induces self-repaired acute lung injury. However, the mechanism of repair has been unclear. Heme-oxygenase (HO)-1, which catalyzes heme breakdown, acts as an inducible defense against oxidative stress and plays an important role in inflammation. The objective of this study was to test the role of HO-1 in lung injury caused by intratracheal instillation of red cells. Forty healthy, male Sprague-Dawley rats were randomly divided into five groups: normal group, saline group, erythrocyte group, erythrocyte+zinc-protoporphyrin (ZnPP, HO-1 inhibitor) group and saline+ZnPP group. At 2 days after intratracheal instillation of red cells, lung tissues and lavage samples were isolated for biochemical determinations and histological measurements. Histological analysis revealed that administration of ZnPP worsened the acute lung injury induced by instilled erythrocytes. HO-1 was over-expressed in the erythrocyte group and in the erythrocyte + ZnPP group. Compared with the erythrocyte + ZnPP group, the levels of total protein, lactate dehydrogenase and tumor necrosis factor-alpha in the lavage were lower (P < 0.01), while the level of interleukin-10 was higher in the erythrocyte group (P < 0.01). HO-1 protects against erythrocyte-induced inflammatory injury in lung.

  17. Chronic intratracheal application of the soluble guanylyl cyclase stimulator BAY 41-8543 ameliorates experimental pulmonary hypertension.

    Science.gov (United States)

    Amirjanians, Matthieu; Egemnazarov, Bakytbek; Sydykov, Akylbek; Kojonazarov, Baktybek; Brandes, Ralf; Luitel, Himal; Pradhan, Kabita; Stasch, Johannes-Peter; Redlich, Gorden; Weissmann, Norbert; Grimminger, Friedrich; Seeger, Werner; Ghofrani, Hossein; Schermuly, Ralph

    2017-05-02

    Dysfunction of the NO/sGC/cGMP signaling pathway has been implicated in the pathogenesis of pulmonary hypertension (PH). Therefore, agents stimulating cGMP synthesis via sGC are important therapeutic options for treatment of PH patients. An unwanted effect of this novel class of drugs is their systemic hypotensive effect. We tested the hypothesis that aerosolized intra-tracheal delivery of the sGC stimulator BAY41-8543 could diminish its systemic vasodilating effect.Pharmacodynamics and -kinetics of BAY41-8543 after single intra-tracheal delivery was tested in healthy rats. Four weeks after a single injection of monocrotaline (MCT, 60 mg/kg s.c.), rats were randomized to a two-week treatment with either placebo, BAY 41-8543 (10 mg/kg per os (PO)) or intra-tracheal (IT) instillation (3 mg/kg or 1 mg/kg).Circulating concentrations of the drug 10 mg/kg PO and 3 mg/kg IT were comparable. BAY 41-8543 was detected in the lung tissue and broncho-alveolar fluid after IT delivery at higher concentrations than after PO administration. Systemic arterial pressure transiently decreased after oral BAY 41-8543 and was unaffected by intratracheal instillation of the drug. PO 10 mg/kg and IT 3 mg/kg regimens partially reversed pulmonary hypertension and improved heart function in MCT-injected rats. Minor efficacy was noted in rats treated IT with 1 mg/kg. The degree of pulmonary vascular remodeling was largely reversed in all treatment groups.Intratracheal administration of BAY 41-8543 reverses PAH and vascular structural remodeling in MCT-treated rats. Local lung delivery is not associated with systemic blood pressure lowering and represents thus a further development of PH treatment with sGC stimulators.

  18. Inflammation and Vascular Effects after Repeated Intratracheal Instillations of Carbon Black and Lipopolysaccharide

    DEFF Research Database (Denmark)

    Christophersen, Daniel Vest; Jacobsen, Nicklas Raun; Jensen, Ditte Marie

    2016-01-01

    mediators in plasma of exposed ApoE-/- mice was assessed in aorta rings isolated from naive C57BL/6 mice. Pulmonary exposure to CB and/or LPS resulted in pulmonary inflammation with a robust influx of neutrophils. The CB exposure did not promote plaque progression in aorta or BCA. Incubation with 0......Inflammation and oxidative stress are considered the main drivers of vasomotor dysfunction and progression of atherosclerosis after inhalation of particulate matter. In addition, new studies have shown that particle exposure can induce the level of bioactive mediators in serum, driving vascular......-and systemic toxicity. We aimed to investigate if pulmonary inflammation would accelerate nanoparticle-induced atherosclerotic plaque progression in Apolipoprotein E knockout (ApoE-/-) mice. ApoE-/- mice were exposed to vehicle, 8.53 or 25.6 mu g nanosized carbon black (CB) alone or spiked with LPS (0.2 mu g...

  19. Cardiac Ischemia Reperfusion Injury Following Instillation of 20 nm Citrate-capped Nanosilver

    Energy Technology Data Exchange (ETDEWEB)

    Becak DP, Holland NA; Shannahan, Jonathan H.

    2015-01-01

    Background: Silver nanoparticles (AgNP) have garnered much interest due to their antimicrobial properties, becoming one of the most utilized nano scale materials. However, any potential evocable cardiovascular injury associated with exposure has not been previously reported. We have previously demonstrated expansion of myocardial infarction after intratracheal (IT) instillation of other nanomaterials. We hypothesized that pulmonary exposure to Ag core AgNP induces persistent increase in circulating cytokines, expansion of cardiac ischemia-reperfusion (I/R) injury and associated with altered coronary vessel reactivity. Methods: Male Sprague-Dawley rats were exposed to 200 µg of 20 nm citrate capped Ag core AgNP, or a citrate vehicle intratracheally (IT). One and 7 days following IT instillation lungs were evaluated for inflammation and silver presence, serum was analyzed for concentrations of selected cytokines, and cardiac I/R injury and coronary artery reactivity was assessed. Results: AgNP instillation resulted in modest pulmonary injury with detection of silver in lung tissue and infiltrating cells, elevation of serum cytokines: G-CSF, MIP-1α, IL-1β, IL-2, IL-6, IL-13, IL-10, IL-18, IL-17, TNFα, and RANTES, expansion of I/R injury and depression of the coronary vessel reactivity at 1 day post IT compared to vehicle treated rats. Seven days post IT instillation was associated with persistent detection of silver in lungs, elevation in cytokines: IL-2, IL-13, and TNFα and expansion of I/R injury. Conclusions: Based on these data, IT instillation of AgNP increases circulating levels of several cytokines, which may contribute to persistent expansion of I/R injury possibly through an impaired vascular responsiveness.

  20. Characterization of a Mouse Model of Emphysema Induced by Multiple Instillations of Low-Dose Elastase

    Directory of Open Access Journals (Sweden)

    Milena V. Oliveira

    2016-10-01

    Full Text Available Many experimental models have been proposed to study the pathophysiological features of emphysema, as well as to search for new therapeutic approaches for acute or chronically injured lung parenchyma. We aimed to characterize an emphysema model induced by multiple instillations of elastase by tracking the changes in inflammation, remodeling, and cardiac function after each instillation. Forty-eight C57BL/6 mice were randomly assigned across 2 groups. Emphysema (ELA animals received 1, 2, 3, or 4 intratracheal instillations of pancreatic porcine elastase (PPE, 0.2 IU with a 1-week interval between them. Controls (C received saline following the same protocol. Before and after implementation of the protocol, animals underwent echocardiographic analysis. After the first instillation of PPE, the percentage of mononuclear cells in the lung parenchyma was increased compared to C (p = 0.0001. The second instillation resulted in hyperinflated alveoli, increased mean linear intercept, and reduced elastic fiber content in lung parenchyma compared to C (p=0.0197. Following the third instillation, neutrophils and collagen fiber content in alveolar septa and airways were increased, whereas static lung elastance was reduced compared to C (p=0.0094. After the fourth instillation, the percentage of M1 macrophages in lungs; levels of interleukin-1beta, keratinocyte-derived chemokine, hepatocyte growth factor, and vascular endothelial growth factor; and collagen fiber content in the pulmonary vessel wall were increased compared to C (p=0.0096. At this time point, pulmonary arterial hypertension was apparent, with increased diastolic right ventricular wall thickness. In conclusion, the initial phase of emphysema was characterized by lung inflammation with predominance of mononuclear cells, whereas at the late stage, impairment of pulmonary and cardiovascular functions was observed. This model enables analysis of therapies at different time points during controlled

  1. The delayed lung responses to single and repeated intratracheal administration of pure cobalt and hard metal powder in the rat.

    Science.gov (United States)

    Lasfargues, G; Lardot, C; Delos, M; Lauwerys, R; Lison, D

    1995-05-01

    Epidemiological and clinical studies suggest that inhalation of cobalt metal dust (Co) mixed with tungsten carbide particles (WC), but not of cobalt dust alone, may cause interstitial pulmonary lesions (hard metal disease). In previous experimental studies in the rat, we have demonstrated the greater acute pulmonary toxicity of a WC-Co mixture compared to Co or WC alone. The present study was undertaken to compare in the same animal model the delayed lung response after intratracheal administration of Co or WC-Co particles (cobalt particle 6.3 wt%). The responses were also compared with those obtained after treatment with arsenic trioxide and crystalline silica used a reference materials producing an acute toxic insult and a progressive fibrogenic response, respectively. Cellular (total and differential counts) and biochemical parameters (LDH, N-acetyl-beta-D-glucosaminidase, total protein, albumin, fibronectin, and hyaluronic acid) were measured in bronchoalveolar lavage fluid following single and repeated intratracheal instillations. The results indicate that the delayed lung response observed after WC-Co is different from that after cobalt metal alone. A single intratracheal dose of WC-Co (1, 5, or 10 mg/100 g body wt) induced an acute alveolitis which persisted for at least 1 month. Four months after a single instillation of WC-Co, no clear histological lung fibrosis could however be evidenced, indicating a reversibility of the lesions. The effects of cobalt (0.06, 0.3, or 0.6 mg/100 g body wt) or tungsten carbide alone (1, 5, 10 mg/ 100 g body wt) were very modest, if any. Following repeated intratracheal instillations (four administrations at 1-month interval), increased lung hydroxyproline content and histopathological evidence of interstitial fibrosis were observed after WC-Co (4 x 1 mg/100 g body wt), but not after administration of each component separately, i.e., Co (4 x 0.06 mg/100 g body wt) or WC (4 x 1 mg/100 g body wt). The mechanism of the fibrotic

  2. Enhanced bioavailability of opiates after intratracheal administration

    Energy Technology Data Exchange (ETDEWEB)

    Findlay, J.W.A.; Jones, E.C.; McNulty, M.J.

    1986-03-01

    Several opiate analgesics have low oral bioavailabilities in the dog because of presystemic metabolism. Intratracheal administration may circumvent this first-pass effect. Three anesthetized beagles received 5-mg/kg doses of codeine phosphate intratracheally (i.t.), orally (p.o.) and intravenously (i.v.) in a crossover study. The following drugs were also studied in similar experiments: ethylmorphine hydrochloride (5 mg/kg), pholcodine bitartrate (10 mg/kg, hydrocodone bitartrate (4 mg/kg) and morphine sulfate (2.5 mg/kg). Plasma drug concentrations over the 24- to 48-hr periods after drug administrations were determined by radioimmunoassays. I.t. bioavailabilities (codeine (84%), ethylmorphine (100%), and morphine (87%)) of drugs with poor oral availabilities were all markedly higher than the corresponding oral values (14, 26, and 23%, respectively). I.t. bioavailabilities of pholcodine (93%) and hydrocodone (92%), which have good oral availabilities (74 and 79%, respectively), were also enhanced. In all cases, peak plasma concentrations occurred more rapidly after i.t. (0.08-0.17 hr) than after oral (0.5-2 hr) dosing and i.t. disposition often resembled i.v. kinetics. I.t. administration may be a valuable alternative dosing route, providing rapid onset of pharmacological activity for potent drugs with poor oral bioavailability.

  3. Acute and subacute pulmonary toxicity and mortality in mice after intratracheal instillation of ZnO nanoparticles in three laboratories

    DEFF Research Database (Denmark)

    Jacobsen, Nicklas Raun; Stoeger, Tobias; van den Brule, Sybille

    2015-01-01

    Inhalation is the main pathway of ZnO exposure in the occupational environment but only few studies have addressed toxic effects after pulmonary exposure to ZnO nanoparticles (NP). Here we present results from three studies of pulmonary exposure and toxicity of ZnO NP in mice. The studies were pr...

  4. Intratracheal Bleomycin Aerosolization: The Best Route of Administration for a Scalable and Homogeneous Pulmonary Fibrosis Rat Model?

    Directory of Open Access Journals (Sweden)

    Alexandre Robbe

    2015-01-01

    Full Text Available Idiopathic pulmonary fibrosis (IPF is a chronic disease with a poor prognosis and is characterized by the accumulation of fibrotic tissue in lungs resulting from a dysfunction in the healing process. In humans, the pathological process is patchy and temporally heterogeneous and the exact mechanisms remain poorly understood. Different animal models were thus developed. Among these, intratracheal administration of bleomycin (BML is one of the most frequently used methods to induce lung fibrosis in rodents. In the present study, we first characterized histologically the time-course of lung alteration in rats submitted to BLM instillation. Heterogeneous damages were observed among lungs, consisting in an inflammatory phase at early time-points. It was followed by a transition to a fibrotic state characterized by an increased myofibroblast number and collagen accumulation. We then compared instillation and aerosolization routes of BLM administration. The fibrotic process was studied in each pulmonary lobe using a modified Ashcroft scale. The two quantification methods were confronted and the interobserver variability evaluated. Both methods induced fibrosis development as demonstrated by a similar progression of the highest modified Ashcroft score. However, we highlighted that aerosolization allows a more homogeneous distribution of lesions among lungs, with a persistence of higher grade damages upon time.

  5. Lentivirus-ABCG1 instillation reduces lipid accumulation and improves lung compliance in GM-CSF knock-out mice

    Energy Technology Data Exchange (ETDEWEB)

    Malur, Anagha; Huizar, Isham [Program in Lung Cell Biology and Translational Research, Division of Pulmonary, Critical Care and Sleep Medicine, East Carolina University, Greenville, NC (United States); Wells, Greg [Department of Microbiology and Immunology, East Carolina University, Greenville, NC (United States); Barna, Barbara P. [Program in Lung Cell Biology and Translational Research, Division of Pulmonary, Critical Care and Sleep Medicine, East Carolina University, Greenville, NC (United States); Malur, Achut G. [Department of Microbiology and Immunology, East Carolina University, Greenville, NC (United States); Thomassen, Mary Jane, E-mail: thomassenm@ecu.edu [Program in Lung Cell Biology and Translational Research, Division of Pulmonary, Critical Care and Sleep Medicine, East Carolina University, Greenville, NC (United States); Department of Microbiology and Immunology, East Carolina University, Greenville, NC (United States)

    2011-11-18

    Highlights: Black-Right-Pointing-Pointer Lentivirus-ABCG1 reduces lipid accumulation in lungs of GM-CSF knock-out mice. Black-Right-Pointing-Pointer Up-regulation of ABCG1 improves lung function. Black-Right-Pointing-Pointer Upregulation of ABCG1 improves surfactant metabolism. -- Abstract: We have shown decreased expression of the nuclear transcription factor, peroxisome proliferator-activated receptor-gamma (PPAR{gamma}) and the PPAR{gamma}-regulated ATP-binding cassette transporter G1 (ABCG1) in alveolar macrophages from patients with pulmonary alveolar proteinosis (PAP). PAP patients also exhibit neutralizing antibodies to granulocyte-macrophage colony stimulating factor (GM-CSF), an upregulator of PPAR{gamma}. In association with functional GM-CSF deficiency, PAP lung is characterized by surfactant-filled alveolar spaces and lipid-filled alveolar macrophages. Similar pathology characterizes GM-CSF knock-out (KO) mice. We reported previously that intratracheal instillation of a lentivirus (lenti)-PPAR{gamma} plasmid into GM-CSF KO animals elevated ABCG1 and reduced alveolar macrophage lipid accumulation. Here, we hypothesized that instillation of lenti-ABCG1 might be sufficient to decrease lipid accumulation and improve pulmonary function in GM-CSF KO mice. Animals received intratracheal instillation of lenti-ABCG1 or control lenti-enhanced Green Fluorescent Protein (eGFP) plasmids and alveolar macrophages were harvested 10 days later. Alveolar macrophage transduction efficiency was 79% as shown by lenti-eGFP fluorescence. Quantitative PCR analyses indicated a threefold (p = 0.0005) increase in ABCG1 expression with no change of PPAR{gamma} or ABCA1 in alveolar macrophages of lenti-ABCG1 treated mice. ABCG1 was unchanged in control lenti-eGFP and PBS-instilled groups. Oil Red O staining detected reduced intracellular neutral lipid in alveolar macrophages from lenti-ABCG1 treated mice. Extracellular cholesterol and phospholipids were also decreased as shown by

  6. Successful treatment of intratracheal cuterebrosis in two cats.

    Science.gov (United States)

    Dvorak, L D; Bay, J D; Crouch, D T; Corwin, R M

    2000-01-01

    Two cases of feline intratracheal myiasis due to Cuterebra spp. larvae are reported. Both cats presented with inspiratory dyspnea and a nonproductive cough. One larva was successfully removed during thoracotomy, and the other was removed during bronchoscopy using forceps passed through a bronchoscope operating channel. Clinical signs were alleviated following removal of the larvae.

  7. Topical medication instillation techniques for glaucoma.

    Science.gov (United States)

    Xu, Li; Wang, Xuemei; Wu, Meijing

    2017-02-20

    Glaucoma is a leading cause of irreversible blindness worldwide and the second most common cause of blindness after cataracts. The primary treatment for glaucoma aims to lower intraocular pressure (IOP) with the use of topical medicines. Topical medication instillation techniques, such as eyelid closure and nasolacrimal occlusion when instilling drops, have been proposed as potential methods to increase ocular absorption and decrease systemic absorption of the drops. To investigate the effectiveness of topical medication instillation techniques compared with usual care or another method of instillation of topical medication in the management of glaucoma or ocular hypertension. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2016, Issue 12), MEDLINE Ovid (1946 to 8 December 2016), Embase Ovid (1947 to 8 December 2016), PubMed (1948 to 8 December 2016), LILACS (Latin American and Caribbean Health Sciences Literature Database) (1982 to 8 December 2016), International Pharmaceutical Abstracts Database (1970 to 8 December 2016), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com) (last searched 13 May 2013), ClinicalTrials.gov (www.clinicaltrials.gov) (searched 8 December 2016) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en) (searched 8 December 2016). We did not use any date or language restrictions in the electronic searches for trials. We included randomized controlled trials which had compared any topical medication instillation technique with usual care or a different method of instillation of topical medication. Two review authors independently screened records from the searches for eligibility, assessed the risk of bias, and extracted data. We followed methods recommended by Cochrane. We identified two trials (122 eyes of 61 participants) that had evaluated a topical medication instillation technique. We

  8. Pulmonary toxicity of nanomaterials: a critical comparison of published in vitro assays and in vivo inhalation or instillation studies.

    Science.gov (United States)

    Landsiedel, Robert; Sauer, Ursula G; Ma-Hock, Lan; Schnekenburger, Jürgen; Wiemann, Martin

    2014-11-01

    To date, guidance on how to incorporate in vitro assays into integrated approaches for testing and assessment of nanomaterials is unavailable. In addressing this shortage, this review compares data from in vitro studies to results from in vivo inhalation or intratracheal instillation studies. Globular nanomaterials (ion-shedding silver and zinc oxide, poorly soluble titanium dioxide and cerium dioxide, and partly soluble amorphous silicon dioxide) and nanomaterials with higher aspect ratios (multiwalled carbon nanotubes) were assessed focusing on the Organisation for Economic Co-Operation and Development (OECD) reference nanomaterials for these substances. If in vitro assays are performed with dosages that reflect effective in vivo dosages, the mechanisms of nanomaterial toxicity can be assessed. In early tiers of integrated approaches for testing and assessment, knowledge on mechanisms of toxicity serves to group nanomaterials thereby reducing the need for animal testing.

  9. Transoral intratracheal inoculation method for use with neonatal rats.

    Science.gov (United States)

    Martínez-Burnes, J; López, A; Lemke, K; Dobbin, G

    2001-04-01

    Studying the effects of toxic and infective compounds on the respiratory system requires a reliable method for delivering inoculum into the distal region of the lung. Although transoral intratracheal inoculation methods have been well documented for adult rats, to the authors' knowledge, a reliable method has not been validated for neonatal rats. The purpose of the study reported here was to develop a simple method for transoral inoculation in rat neonates. Seven-day-old Fischer 344 rats were anesthetized with halothane, and a spinal needle was inserted in the tracheal lumen, by use of illumination and a modified otoscope. Meconium was injected into the lungs as a marker, and the neonates were kept under close observation. After euthanasia at 24 h, lungs were removed and fixed in formalin, and the microscopic distribution of the inoculum was assessed in the left, right cranial, middle, median, and caudal lung lobes. Microscopic examination of lungs indicated that intratracheal inoculation was achieved in 100% of neonatal lungs and the inoculum was consistently distributed in the alveoli of all pulmonary lobes. Important complications or mortality were not observed in the neonates. Intratracheal inoculation of neonatal rats is possible by use of a modified otoscope for transoral illumination. This technique is simple and reproducible and ensures, without complications, widespread distribution of inoculum in the lungs of neonatal rats.

  10. Attenuation of lung inflammation and fibrosis in CD69-deficient mice after intratracheal bleomycin

    Directory of Open Access Journals (Sweden)

    Matsunaga Hirofumi

    2011-10-01

    Full Text Available Abstract Background Cluster of differentiation 69 (CD69, an early activation marker antigen on T and B cells, is also expressed on activated macrophages and neutrophils, suggesting that CD69 may play a role in inflammatory diseases. To determine the effect of CD69 deficiency on bleomycin(BLM-induced lung injury, we evaluated the inflammatory response following intratracheal BLM administration and the subsequent fibrotic changes in wild type (WT and CD69-deficient (CD69-/- mice. Methods The mice received a single dose of 3 mg/kg body weight of BLM and were sacrificed at 7 or 14 days post-instillation (dpi. Lung inflammation in the acute phase (7 dpi was investigated by differential cell counts and cytokine array analyses of bronchoalveolar lavage fluid. In addition, lung fibrotic changes were evaluated at 14 dpi by histopathology and collagen assays. We also used reverse transcription polymerase chain reaction to measure the mRNA expression level of transforming growth factor β1 (TGF-β1 in the lungs of BLM-treated mice. Results CD69-/- mice exhibited less lung damage than WT mice, as shown by reductions in the following indices: (1 loss of body weight, (2 wet/dry ratio of lung, (3 cytokine levels in BALF, (4 histological evidence of lung injury, (5 lung collagen deposition, and (6 TGF-β1 mRNA expression in the lung. Conclusion The present study clearly demonstrates that CD69 plays an important role in the progression of lung injury induced by BLM.

  11. Gene expression profiling in rat kidney after intratracheal exposure to cadmium-doped nanoparticles

    International Nuclear Information System (INIS)

    Coccini, Teresa; Roda, Elisa; Fabbri, Marco; Sacco, Maria Grazia; Gribaldo, Laura; Manzo, Luigi

    2012-01-01

    While nephrotoxicity of cadmium is well documented, very limited information exists on renal effects of exposure to cadmium-containing nanomaterials. In this work, “omics” methodologies have been used to assess the action of cadmium-containing silica nanoparticles (Cd-SiNPs) in the kidney of Sprague-Dawley rats exposed intratracheally. Groups of animals received a single dose of Cd-SiNPs (1 mg/rat), CdCl 2 (400 μg/rat) or 0.1 ml saline (control). Renal gene expression was evaluated 7 and 30 days post exposure by DNA microarray technology using the Agilent Whole Rat Genome Microarray 4x44K. Gene modulating effects were observed in kidney at both time periods after treatment with Cd-SiNPs. The number of differentially expressed genes being 139 and 153 at the post exposure days 7 and 30, respectively. Renal gene expression changes were also observed in the kidney of CdCl 2 -treated rats with a total of 253 and 70 probes modulated at 7 and 30 days, respectively. Analysis of renal gene expression profiles at day 7 indicated in both Cd-SiNP and CdCl 2 groups downregulation of several cluster genes linked to immune function, oxidative stress, and inflammation processes. Differing from day 7, the majority of cluster gene categories modified by nanoparticles in kidney 30 days after dosing were genes implicated in cell regulation and apoptosis. Modest renal gene expression changes were observed at day 30 in rats treated with CdCl 2 . These results indicate that kidney may be a susceptible target for subtle long-lasting molecular alterations produced by cadmium nanoparticles locally instilled in the lung.

  12. Single Silver Nanoparticle Instillation Induced Early and Persisting Moderate Cortical Damage in Rat Kidneys

    Directory of Open Access Journals (Sweden)

    Elisa Roda

    2017-10-01

    Full Text Available The potential toxic effects of silver nanoparticles (AgNPs, administered by a single intratracheal instillation (i.t, was assessed in a rat model using commercial physico-chemical characterized nanosilver. Histopathological changes, overall toxic response and oxidative stress (kidney and plasma protein carbonylation, paralleled by ultrastructural observations (TEM, were evaluated to examine renal responses 7 and 28 days after i.t. application of a low AgNP dose (50 µg/rat, compared to an equivalent dose of ionic silver (7 µg AgNO3/rat. The AgNPs caused moderate renal histopathological and ultrastructural alteration, in a region-specific manner, being the cortex the most affected area. Notably, the bulk AgNO3, caused similar adverse effects with a slightly more marked extent, also triggering apoptotic phenomena. Specifically, 7 days after exposure to both AgNPs and AgNO3, dilatation of the intercapillary and peripheral Bowman’s space was observed, together with glomerular shrinkage. At day 28, these effects still persisted after both treatments, accompanied by an additional injury involving the vascular component of the mesangium, with interstitial micro-hemorrhages. Neither AgNPs nor AgNO3 induced oxidative stress effects in kidneys and plasma, at either time point. The AgNP-induced moderate renal effects indicate that, despite their benefits, novel AgNPs employed in consumer products need exhaustive investigation to ensure public health safety.

  13. Ectopic Intratracheal Thyroid: A Rare Cause of Airway Obstruction

    Directory of Open Access Journals (Sweden)

    Waheed Rahman

    2018-01-01

    Full Text Available Ectopic intratracheal thyroid tissue (EITT is a rare abnormality with only limited cases reported so far. The presenting symptoms can be very similar to those of bronchial asthma. We discuss the case of a 29-year-old man with subglottic ectopic thyroid, with a history of thyroid surgery for goiter, which has been managed with laser-assisted endoscopic approach. We have also included presenting symptoms, pathophysiology, diagnosis, and management of EITT. We aim to include EITT in the differentials of airway obstruction, particularly in those patients who have goiter or previous thyroid surgeries.

  14. Subchronic immunotoxicity and screening of reproductive toxicity and developmental immunotoxicity following single instillation of HIPCO-single-walled carbon nanotubes: purity-based comparison.

    Science.gov (United States)

    Park, Eun-Jung; Choi, Je; Kim, Jae-Ho; Lee, Byoung-Seok; Yoon, Cheolho; Jeong, Uiseok; Kim, Younghun

    2016-10-01

    Impurity has been suggested as an important factor determining toxicity following exposure to single-walled carbon nanotubes (SWCNTs). In this study, we first compared immunotoxicity based on iron content on day 90 after a single intratracheal instillation of SWCNTs in male and female mice. The inflammatory responses were generally stronger in mice exposed to acid-purified (P)-SWCNTs compared to raw (R)-SWCNTs. In addition, both R- and P-SWCNTs induced Th1-polarized immune responses with apoptotic death of BAL cells and systemically impaired the function of antigen-presenting cells (APC). We also screened reproductive and developmental toxicity by cohabitating male and female mice on day 14 after instillation. Interestingly, the pregnancy rate rapidly decreased following exposure to both types of SWCNTs, especially R-SWCNTs. In addition, we investigated developmental immunotoxicity of the offspring on day 28 after exposure to both types of SWCNTs. Their hematological changes were clearer relative to those of the parents and a significant decrease in the alkaline phosphatase and potassium levels was observed in mice of both sexes exposed to the higher dose of R- and P-SWCNTs. In conclusion, we suggest that SWCNTs may induce Th1-polarized immune responses accompanied by suppression of APC function on day 90 after a single instillation without significant iron content dependance. In addition, the consecutive exposure of SWCNTs to the subsequent generation may exacerbate metabolic and hematological disturbance. Furthermore, our results underscore the need to clarify the reproductive and developmental health effects of SWCNTs.

  15. Comparison of efficacy of intraperitoneal instillation of bupivacaine ...

    African Journals Online (AJOL)

    Comparison of efficacy of intraperitoneal instillation of bupivacaine alone with bupivacaine – fentanyl and bupivacaine –tramadol combination for alleviation of post-operative pain following laparoscopic cholecystectomy: a randomized prospective study.

  16. Instillation of coarse ash particulate matter and lipopolysaccharide produces a systemic inflammatory response in mice

    Energy Technology Data Exchange (ETDEWEB)

    Finnerty, K.; Choi, J.E.; Lau, A.; Davis-Gorman, G.; Diven, C.; Seaver, N.; Linak, W.P.; Witten, M.; McDonagh, P.F. [Arizona Health Science Center, Tucson, AZ (United States)

    2007-07-01

    Coronary ischemic events increase significantly following a 'bad air' day. Ambient particulate matter (PM10) is the pollutant most strongly associated with these events. PM10 produces inflammatory injury to the lower airways. It is not clear, however, whether pulmonary inflammation translates to a systemic response. Lipopolysaccharide (LPS) is a proinflammatory molecule often associated with the coarse fraction of PM. It was hypothesized that PM > 2.5 from coal plus LPS induce pulmonary inflammation leading to a systemic inflammatory response. Mice were intratracheally instilled with saline, PM (200 {mu} g), PM+ LPS10 (PM+ 10 {mu} g LPS), or PM+ LPS100 (PM+ 100 {mu} g LPS). Eighteen hours later, histologic analysis was performed on lungs from each group. Pulmonary and systemic inflammation were assessed by measuring the proinflammatory cytokines tumor necrosis factor (TNF)-{alpha} and interleukin (IL)-6 in the pulmonary supernatant and plasma. In a follow-up study, the effects of LPS alone were assessed. Histologic analysis revealed a dose-dependent elevation in pulmonary inflammation with all treatments. Pulmonary TNF-{alpha} and IL-6 both increased significantly with PM+ LPS100 treatment. Regarding plasma, TNF-{alpha} significantly increased in both PM+ LPS10 and PM+ LPS100 treatments. For plasma IL-6, all groups tended to rise with a significant increase in the PM+ LPS100 group. The results of the follow-up study indicate that the responses to PM+ LPS were not due to LPS alone. These results suggest that coarse coal fly ash PM > 2.5 combined with LPS produced pulmonary and systemic inflammatory responses. The resulting low-level systemic inflammation may contribute to the increased severity of ischemic heart disease observed immediately following a bad air day.

  17. Pulmonary instillation of low doses of titanium dioxide nanoparticles in mice leads to particle retention and gene expression changes in the absence of inflammation

    Energy Technology Data Exchange (ETDEWEB)

    Husain, Mainul, E-mail: mainul.husain@hc-sc.gc.ca [Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario K1A 0K9 (Canada); Saber, Anne T., E-mail: ats@nrcwe.dk [The Danish NanoSafety Centre, National Research Centre for the Working Environment, Copenhagen DK-2100 (Denmark); Guo, Charles, E-mail: charles.guo@hc-sc.gc.ca [Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario K1A 0K9 (Canada); Jacobsen, Nicklas R., E-mail: nrj@nrcwe.dk [The Danish NanoSafety Centre, National Research Centre for the Working Environment, Copenhagen DK-2100 (Denmark); Jensen, Keld A., E-mail: kaj@nrcwe.dk [The Danish NanoSafety Centre, National Research Centre for the Working Environment, Copenhagen DK-2100 (Denmark); Yauk, Carole L., E-mail: carole.yauk@hc-sc.gc.ca [Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario K1A 0K9 (Canada); Williams, Andrew, E-mail: andrew.williams@hc-sc.gc.ca [The Danish NanoSafety Centre, National Research Centre for the Working Environment, Copenhagen DK-2100 (Denmark); Vogel, Ulla, E-mail: ubv@nrcwe.dk [The Danish NanoSafety Centre, National Research Centre for the Working Environment, Copenhagen DK-2100 (Denmark); Department of Micro- and Nanotechnology, Technical University of Denmark, Kgs. Lyngby DK-2800 (Denmark); Wallin, Hakan, E-mail: hwa@nrcwe.dk [The Danish NanoSafety Centre, National Research Centre for the Working Environment, Copenhagen DK-2100 (Denmark); Institute of Public Health, University of Copenhagen, Copenhagen DK-1014 (Denmark); Halappanavar, Sabina, E-mail: sabina.halappanavar@hc-sc.gc.ca [Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario K1A 0K9 (Canada)

    2013-06-15

    We investigated gene expression, protein synthesis, and particle retention in mouse lungs following intratracheal instillation of varying doses of nano-sized titanium dioxide (nano-TiO{sub 2}). Female C57BL/6 mice were exposed to rutile nano-TiO{sub 2} via single intratracheal instillations of 18, 54, and 162 μg/mouse. Mice were sampled 1, 3, and 28 days post-exposure. The deposition of nano-TiO{sub 2} in the lungs was assessed using nanoscale hyperspectral microscopy. Biological responses in the pulmonary system were analyzed using DNA microarrays, pathway-specific real-time RT-PCR (qPCR), gene-specific qPCR arrays, and tissue protein ELISA. Hyperspectral mapping showed dose-dependent retention of nano-TiO{sub 2} in the lungs up to 28 days post-instillation. DNA microarray analysis revealed approximately 3000 genes that were altered across all treatment groups (± 1.3 fold; p < 0.1). Several inflammatory mediators changed in a dose- and time-dependent manner at both the mRNA and protein level. Although no influx of neutrophils was detected at the low dose, changes in the expression of several genes and proteins associated with inflammation were observed. Resolving inflammation at the medium dose, and lack of neutrophil influx in the lung fluid at the low dose, were associated with down-regulation of genes involved in ion homeostasis and muscle regulation. Our gene expression results imply that retention of nano-TiO{sub 2} in the absence of inflammation over time may potentially perturb calcium and ion homeostasis, and affect smooth muscle activities. - Highlights: • Pulmonary effects following exposure to low doses of nano-TiO{sub 2} were examined. • Particle retention in lungs was assessed using nanoscale hyperspectral microscopy. • Particles persisted up to 28 days in lungs in all dose groups. • Inflammation was the pathway affected in the high dose group at all time points. • Ion homeostasis and muscle activity pathways were affected in the low dose

  18. Lavage drain extension for local anaesthetic instillation into ...

    African Journals Online (AJOL)

    Thirty-one patients who had undergone abdominoplasty procedures were selected for instillation of a local anaesthetic preparation, ropivacaine (Naropin, AstraZeneca) into the wound site on day 1 and 2 after surgery, followed by early mobilisation. Efficacy of the system, patient comfort and mobilisation were documented.

  19. The effect of normal saline instillation on cardiorespiratory ...

    African Journals Online (AJOL)

    The effect of normal saline instillation on cardiorespiratory parameters in intubated cardiothoracic patients. ... S Schmollgruber, JC Bruce, JC Rachidi, PJ Becker ... Even though the patient population was at high risk of haemodynamic disturbance and hypoxia during this manoeuvre, there was no meaningful clinical effect; ...

  20. Intraocular penetration of sequentially instilled topical moxifloxacin, gatifloxacin, and levofloxacin

    Directory of Open Access Journals (Sweden)

    Koji Sugioka

    2009-10-01

    Full Text Available Koji Sugioka1, Masahiko Fukuda1, Shohei Komoto1, Motoki Itahashi1, Masakazu Yamada2, Yoshikazu Shimomura11Department of Ophthalmology, Kinki University School of Medicine, Osaka-Sayama City, Osaka, Japan; 2Division for Vision Research, National Institute of Sensory Organs, National Tokyo Medical Center, Tokyo, JapanPurpose: The objective of the study was to compare the intraocular penetration levels of the newer fluoroquinolones, moxifloxacin, gatifloxacin, and levofloxacin in the rabbit’s cornea, aqueous humor, and conjunctiva after topical instillation.Methods: 0.5% moxifloxacin, 0.3% gatifloxacin, and 0.5% levofloxacin were instilled in random sequence in both eyes of nine New Zealand White rabbits at two-minute intervals. Instillation was repeated every 15 minutes for a total of three drops of each fluoroquinolone per eye. Three additional animals had only moxifloxacin instilled bilaterally using the same schedule. Sixty minutes after the final instillation, the rabbits were sacrificed for determination of corneal, aqueous humor, and conjunctival fluoroquinolone concentrations using highperformance liquid chromatography.Results: Moxifloxacin achieved significantly higher concentrations than levofloxacin and gatifloxacin in the cornea (P = 0.0102 and P = 0.0006, respectively, aqueous humor (P = 0.0015 and P < 0.0001, respectively, and conjunctiva (P = 0.0191 and P = 0.0236, respectively. Conclusions: 0.5% moxifloxacin eyedrops provided superior intraocular penetration in rabbits’ eyes compared with the two other fluoroquinolones, 0.5% levofloxacin and 0.3% gatifloxacin.Keywords: fluoroquinolone, gatifloxacin, levofloxacin, moxifloxacin, penetration, rabbit

  1. Intratracheal catheter suction removes the same volume of meconium with less impact on desaturation compared with meconium aspirator in meconium aspiration syndrome.

    Science.gov (United States)

    Akazawa, Yohei; Ishida, Takefumi; Baba, Atsushi; Hiroma, Takehiko; Nakamura, Tomohiko

    2010-08-01

    To evaluate the impact of suction technique on the rate of meconium removal, oxygenation, and hemodynamics in an animal experimental model of meconium aspiration syndrome (MAS). MAS was induced in ventilated rabbits using 3.5 ml/kg of 20% human meconium. Tracheal suction with either catheter suction (CS) or meconium aspirator (MA) was performed after meconium instillation. Percentage of meconium collection rate, PaO(2) trends for 2h after tracheal suction, and acute-phase SpO(2) trends were compared between CS and the other three groups, the tube was withdrawn while meconium was aspirated with an MA, then the trachea was reintubated 5, 10 or 15s after suctioning of meconium. Percentage of meconium collection rate and PaO(2) showed no significant differences between groups. The MA group taking 15s for reintubation after meconium suctioning, showed a significantly lower acute-phase SpO(2) than the CS group (Por=90% was also longer in the MA group taking 15s for reintubation than in the CS group (Pmeconium with less impact on desaturation compared with meconium aspiration in an animal model of MAS. Intratracheal CS may be benefit to remove meconium in non-vigorous infants with meconium-stained amniotic fluid at birth. Copyright 2010 Elsevier Ltd. All rights reserved.

  2. Weldability of Stainless Steels

    International Nuclear Information System (INIS)

    Saida, Kazuyoshi

    2010-01-01

    It gives an outline of metallographic properties of welding zone of stainless steels, generation and mechanisms of welding crack and decreasing of corrosion resistance of welding zone. It consists of seven chapters such as introduction, some kinds of stainless steels and properties, metallographic properties of welding zone, weld crack, toughness of welding zone, corrosion resistance and summary. The solidification modes of stainless steels, each solidification mode on the cross section of Fe-Cr-Ni alloy phase diagram, each solidification mode of weld stainless steels metal by electron beam welding, segregation state of alloy elements at each solidification mode, Schaeffler diagram, Delong diagram, effects of (P + S) mass content in % and Cr/Ni equivalent on solidification cracking of weld stainless steels metal, solidification crack susceptibility of weld high purity stainless steels metal, effects of trace impurity elements on solidification crack susceptibility of weld high purity stainless steels metal, ductile fracture susceptibility of weld austenitic stainless steels metal, effects of H2 and ferrite content on generation of crack of weld 25Cr-5N duplex stainless steels, effects of O and N content on toughness of weld SUS 447J1 metals, effect of ferrite content on aging toughness of weld austenitic stainless steel metal, corrosion morphology of welding zone of stainless steels, generation mechanism of knife line attack phenomenon, and corrosion potential of some kinds of metals in seawater at room temperature are illustrated. (S.Y.)

  3. Metallic intratracheal stent application on relapsing polychondritis with severe tracheobronchial malacia

    International Nuclear Information System (INIS)

    Ao Guokun; Zhao Weiguo; Guo Qinyun; Huang Qin

    2007-01-01

    Objective: To evaluate the therapeutic and adverse effects of metallic intratracheal stent placement in relapsing polychondritis with severe tracheobronchial malaeia. Methods: Five tracheal stents had been implanted in three patients with tracheobronchial malaeia. One patient was implanted with two tubular stents in trachea and one 'Y' shaped stent for bilateral bronchi. Another patient used a tubular stent in total tracheal segment. The last patient used a tubular stent in the upper segment of trachea. Results: All the stents were implanted successfully with obvious improvement of dyspnea after the treatment. Conclusions: Metallic intratracheal stent placement can really relieve symptoms and improve the life quality in patients with tracheobronchial malacia caused by relapsing polychondritis. (authors)

  4. Late sensory function after intraoperative capsaicin wound instillation

    DEFF Research Database (Denmark)

    Aasvang, E K; Hansen, J B; Kehlet, H

    2010-01-01

    is partly re-established after skin injection of capsaicin. However, no study has evaluated the long-term effects of wound instillation of purified capsaicin on sensory functions. METHODS: Patients included in a double-blind placebo-controlled randomized study of the analgesic effect of capsaicin after....... placebo group at the 1-week follow-up (Pfunction on the operated side between groups at the pre-operative, 1-week or 2 1/2 year post-operative follow-up (P>0.05). The sensory function......BACKGROUND: Intense capsaicin-induced C-fiber stimulation results in reversible lysis of the nerve soma, thereby making capsaicin wound instillation of potential interest for the treatment of post-operative pain. Clinical histological and short-term sensory studies suggest that the C-fiber function...

  5. Iloprost Instillation in Two Neonates with Pulmonary Hypertension

    International Nuclear Information System (INIS)

    Aktas, S.; Aksu, M.; Hirfanoglu, I. M.; Atalay, Y.; Turkyilmaz, C.; Unal, S.

    2017-01-01

    Pulmonary hypertension may coexist with certain diseases in neonates. Iloprost inhalation is one of the treatments which cause selective pulmonary vasodilatation. Inhalation is not an easy way of drug administration in mechanically ventilated infants; as some exhibit desaturations during inhalation. Moreover, inhalation of drug requires cessation of mechanical ventilation, if patient is on high frequency oscillatory ventilation. We presented two patients with pulmonary hypertension; term baby with congenital diaphragmatic hernia and preterm baby with respiratory distress syndrome; who had iloprost instillation during mechanical ventilation treatment. Iloprost instillation was well tolerated with no side effects in the term patient with diaphragmatic hernia; whereas severe blood pressure fluctuations were observed in the preterm infant. This report may courage administration of iloprost in term neonates with resistant pulmonary hypertension. (author)

  6. Reiter's syndrome postintravesical Bacillus Calmette–Guérin instillations

    Directory of Open Access Journals (Sweden)

    Keng Lim Ng

    2017-03-01

    Full Text Available Intravesical Bacillus Calmette–Guérin (BCG has been a proven and effective immunotherapy treatment for superficial transitional cell carcinoma (TCC of the bladder, especially for high-grade tumors and carcinoma in situ. Nevertheless, significant side effects are associated with BCG instillations, including fever, myalgia, malaise, dysuria, hematuria, and irritable lower urinary tract symptoms. We herein report the case of a patient who developed Reiter's syndrome following intravesical BCG instillations. A 39-year-old Chinese man presented with a 3-week history of dysuria, suprapubic pain, and pain at the tip of the penis postmicturition. Initial investigations revealed that he had microhematuria, and an ultrasound with computed tomography scan of the abdomen showed a bladder mass. Transurethral resection of the bladder tumor was performed and the patient received a single dose of intravesical mitomycin postoperatively. Results of histopathological examination revealed high-grade bladder TCC (G3pT1, and the patient was managed with intravesical BCG for 2 weeks following the surgery. Four weekly cycles of BCG were administered uneventfully; however, before the fifth instillation, the patient complained of urethral discharge, bilateral conjunctivitis, and low back pain. Reiter's syndrome was diagnosed as a rare but known complication of BCG instillation and the BCG immunotherapy was withheld. The patient was treated with nonsteroidal antiinflammatory drugs (for back pain and eye ointment (for conjunctivitis and his condition improved. This case report of Reiter's syndrome should be highlighted as a rare but significant complication of BCG immunotherapy and urologists should have a high index of suspicion to diagnose this rare complication.

  7. Negative-pressure wound therapy with instillation: international consensus guidelines.

    Science.gov (United States)

    Kim, Paul J; Attinger, Christopher E; Steinberg, John S; Evans, Karen K; Lehner, Burkhard; Willy, Christian; Lavery, Larry; Wolvos, Tom; Orgill, Dennis; Ennis, William; Lantis, John; Gabriel, Allen; Schultz, Gregory

    2013-12-01

    Negative-pressure wound therapy with instillation is increasingly utilized as an adjunct therapy for a wide variety of wounds. Despite its growing popularity, there is a paucity of evidence and lack of guidance to provide effective use of this therapy. A panel of experts was convened to provide guidance regarding the appropriate use of negative-pressure wound therapy with instillation. A face-to-face meeting was held where the available evidence was discussed and individual clinical experience with this therapy was shared. Follow-up communication among the panelists continued until consensus was achieved. The final consensus recommendations were derived through more than 80 percent agreement among the panelists. Nine consensus statements were generated that address the appropriate use of negative-pressure wound therapy with instillation. The question of clinical effectiveness of this therapy was not directly addressed by the consensus panel. This document serves as preliminary guidelines until more robust evidence emerges that will support or modify these consensus recommendations.

  8. Toxicokinetics of hexavalent chromium in the rat after intratracheal administration of chromates of different solubilities

    NARCIS (Netherlands)

    Bragt, P.C.; Dura, E.A. van

    1983-01-01

    The kinetics of chromium in the rat after a single intratracheal dose of sodium, zinc or lead 51Cr-chromate have been investigated. Sodium chromate and the less soluble zinc chromate were absorbed into the blood and this resulted in increased excretion of chromium into the urine. The insoluble lead

  9. Recurrent pregnancy-related upper airway obstruction caused by intratracheal ectopic thyroid tissue

    DEFF Research Database (Denmark)

    Døssing, H; Jørgensen, K E; Oster-Jørgensen, E

    1999-01-01

    during her second pregnancy. Her 58-mL multinodular goiter (by ultrasound) was not thought to be responsible for her upper airway symptoms. Therefore, fiber laryngoscopy and computed tomographic (CT) scan were performed and revealed a 20 x 15 x 10 mm intratracheal tumor. After tracheostomy...

  10. Can vacuum-assisted closure and instillation therapy (VAC-Instill therapy) play a role in the treatment of the infected open abdomen?

    Science.gov (United States)

    D'Hondt, M; D'Haeninck, A; Dedrye, L; Penninckx, F; Aerts, R

    2011-03-01

    Severe superimposed infection during open abdomen treatment with development of intra-abdominal sepsis is a challenging complication associated with high mortality rates. We report our experience with VAC-Instill therapy (KCI, San Antonio, USA) used for treatment of an infected open abdomen following pancreatic surgery. A literature search revealed no analogous case reports using VAC-Instill therapy for treatment of an infected laparostomy. The encouraging result of the case presented seems to indicate that VAC-Instill therapy could be used as adjunctive treatment in the management of the infected open abdomen when traditional therapy fails to control the infection.

  11. Systemic BCG-osis following intravesical BCG instillation for bladder carcinoma.

    Science.gov (United States)

    Liaw, Frank; Tan, Yan Yu; Hendry, David

    2017-10-01

    Intravesical instillation of Bacillus Calmette-Guérin (BCG) has been shown to be an effective form of immunotherapy for bladder cancer. This case report describes a patient who develops systemic BCG-osis following intravesical BCG instillation and demonstrates the importance of being aware of more severe complications associated with BCG immunotherapy.

  12. Therapeutic effects and predictive factors for successful intravesical hyaluronic acid instillation in patients with interstitial cystitis/bladder pain syndrome

    Directory of Open Access Journals (Sweden)

    Cheng-Ling Lee

    2015-06-01

    Conclusion: Intravesical HA administrations improved IC symptoms, decreased bladder pain, and decreased frequency after four instillations, and decreased nocturia and increased bladder capacity after completion of all nine instillations. Low-grade glomerulation predicts successful outcome.

  13. Articles comprising ferritic stainless steels

    Science.gov (United States)

    Rakowski, James M.

    2016-06-28

    An article of manufacture comprises a ferritic stainless steel that includes a near-surface region depleted of silicon relative to a remainder of the ferritic stainless steel. The article has a reduced tendency to form an electrically resistive silica layer including silicon derived from the steel when the article is subjected to high temperature oxidizing conditions. The ferritic stainless steel is selected from the group comprising AISI Type 430 stainless steel, AISI Type 439 stainless steel, AISI Type 441 stainless steel, AISI Type 444 stainless steel, and E-BRITE.RTM. alloy, also known as UNS 44627 stainless steel. In certain embodiments, the article of manufacture is a fuel cell interconnect for a solid oxide fuel cell.

  14. Chromium-Makes stainless steel stainless

    Science.gov (United States)

    Kropschot, S.J.; Doebrich, Jeff

    2010-01-01

    Chromium, a steely-gray, lustrous, hard metal that takes a high polish and has a high melting point, is a silvery white, hard, and bright metal plating on steel and other material. Commonly known as chrome, it is one of the most important and indispensable industrial metals because of its hardness and resistance to corrosion. But it is used for more than the production of stainless steel and nonferrous alloys; it is also used to create pigments and chemicals used to process leather.

  15. Nonvalue of Neomycin Instillation after Intermittent Urinary Catheterization

    Science.gov (United States)

    Haldorson, Alice M.; Keys, Thomas F.; Maker, Myron D.; Opitz, Joachim L.

    1978-01-01

    This study evaluated weekly urine cultures of patients with neurogenic bladder disease who underwent intermittent urinary catheterization for bladder retraining. One group of 53 patients in 1974 received regular instillations of 0.1% neomycin after each catheterization. A similar group of 55 patients in 1975 did not receive neomycin and constituted a control group. Distribution of age, sex, diagnosis, and duration of bladder retraining was comparable in both groups. Quantitative bacterial colony counts of 104 to 105 or greater per ml of urine were considered significant. There was no difference in the incidence of bacteriuria between the neomycin-treated group and the control group (53 versus 49%, respectively), and most patients in each group had colony counts >105/ml. Escherichia coli was seen less frequently in neomycin-treated patients (43.4 versus 62.5%), but a greater percentage of infections due to Pseudomonas aeruginosa, group D streptococci, and yeasts was noted in the neomycin-treated group than in the control group (41.5 versus 22.5%). PMID:360984

  16. Mitomycin C instillation following ureterorenoscopic laser ablation of upper urinary tract carcinoma

    Directory of Open Access Journals (Sweden)

    Omar M Aboumarzouk

    2013-01-01

    Conclusions: Using a set standard protocol, MMC can safely be instilled into the UUT after TCC ablation with minimal complications or side effects, good preservation of renal function, and with a low recurrences rate comparable to the literature.

  17. Endotracheal instillation of prostacyclin in preterm infants with persistent pulmonary hypertension

    NARCIS (Netherlands)

    J.N. van den Anker (John); A. de Jaegere (Anne)

    1998-01-01

    textabstractDoes endotracheal instilled prostacyclin (epoprostenol) improve oxygenation in preterm infants with persistent pulmonary hypertension? Four preterm infants were studied. Prostacyclin (50 ng x kg(-1)) was injected as an endotracheal bolus. In two patients the

  18. Alleviating effects of artificial tear instillation on S-1-induced ocular toxicity in dogs.

    Science.gov (United States)

    Kanie, Shohei; Fujieda, Mitsuhiro; Hitotsumachi, Tomoaki; Suzuki, Satoshi; Morita, Fumio; Hakoi, Kazuo; Yasui, Hirofumi

    2017-01-01

    S-1 is an anticancer agent that consists of tegafur, gimeracil, and oteracil potassium at a molar ratio of 1:0.4:1. S-1 is used to treat metastatic and resectable gastric cancer. However, the extensive use of S-1 in clinical practice results in watery eyes, a serious clinical problem, which worsens patients' quality of life. Although repeated instillation of artificial tears is recommended, therapy or prophylaxis against S-1-induced ocular toxicity has not been established. In the present study, we evaluated the alleviating effects of repeated artificial tear instillation on S-1-induced ocular toxicity in dogs. Ten beagle dogs (5 males and 5 females) were orally administered 3 mg/kg/day of S-1 for up to 21 days. Five drops of artificial tears were instilled to the left eye, eight times daily, within 6 hr after S-1 administration. The mean cornea staining score tended to be low in the left eye with repeated artificial tear instillation. In 4 out of 10 dogs, the corneal staining score of the left eye was more than 2-fold lower than that of the right eye. The incidence of dogs indicating normal tear drainage increased and stenosed tear drainage decreased by repeated artificial tear instillation. In conclusion, we demonstrated that artificial tear instillation can alleviate corneal surface damage induced by S-1 in dogs.

  19. High Nitrogen Stainless Steel

    Science.gov (United States)

    2011-07-19

    crack growth (FCG) test (ASTM E 647-95a) - square bar specimen of 0.4x0.4x2.8 in. in L-orientation with a Charpy notch at the mid- length for SCC...Hydrogen Embrittlement in Steel by the Increment Loading Technique. Fractography: After the stress-life fatigue tests , the fracture surface morphology...NAWCADPAX/TR-2011/162 HIGH NITROGEN STAINLESS STEEL by E. U. Lee R. Taylor 19 July 2011 Approved for

  20. A newly developed tool for intra-tracheal temperature and humidity assessment in laryngectomized individuals: the Airway Climate Explorer (ACE)

    NARCIS (Netherlands)

    Zuur, J.K.; Muller, S.H.; Jongh, F.H.C.; Horst, M.J. van der; Shehata, M.; Leeuwen, J. van; Sinaasappel, M.; Hilgers, F.J.M.

    2007-01-01

    The aim of this study is to develop a postlaryngectomy airway climate explorer (ACE) for assessment of intratracheal temperature and humidity and of influence of heat and moisture exchangers (HMEs). Engineering goals were within-device condensation prevention and fast response time characteristics.

  1. Investigation of the pathogenesis of Enterococcus cecorum after intravenous, intratracheal or oral experimental infections of broilers and broiler breeders

    DEFF Research Database (Denmark)

    Thoefner, Ida; Christensen, Jens Peter

    is known concerning transmission and pathogenesis in broilers and their parents. Consequently, a set of experimental E. cecorum infections were conducted in broiler breeders and broilers. The bacteria was inoculated at two doses using intravenous (IV), intratracheal (IT) and oral (PO) route of infection...

  2. Hepatic microsomal phospholipids in rats exposed intratracheally to coal fly ash

    International Nuclear Information System (INIS)

    Srivastava, P.K.; Chauhan, S.S.; Misra, U.K.

    1986-01-01

    The effects of intratracheal administration of fly ash (50 mg/kg body weight, daily for 7 days) on hepatic microsomal phospholipid metabolism has been studied in rats using various phospholipid precursors, viz NaH 2 32 PO 4 , (methyl- 14 C)-choline, and (methyl- 14 C)-methionine. Fly ash administration significantly increased microsomal phosphatidylcholine (PC), and lysophosphatidylcholine (LPC). The incorporation of NaH 2 32 PO 4 into total liver phospholipids, PC and Phosphatidyl ethanolamine (PE) was significantly increased in fly ash-treated rats as compared to the control. Fly ash administration also increased the incorporation of (methyl- 14 C)-choline into microsomal PC. Incorporation of (methyl- 14 C)-methionine into microsomal PC was not affected. Fly ash administration decreased the per cent distribution of arachidonic acid in PC and PE and increased that of oleic acid in PC and of linoleic acid in PE. (orig.)

  3. Hydrogen effects in stainless steel

    International Nuclear Information System (INIS)

    Caskey, G.R. Jr.

    1983-01-01

    The effects of hydrogen on stainless steels have been reviewed and are summarized in this paper. Discussion covers hydrogen solution and transport in stainless steels as well as the effects of hydrogen on deformation and fracture under various loading conditions. Damage is caused also by helium that arises from decay of the hydrogen isotope tritium. Austenitic, ferritic, martensite, and precipitation-hardenable stainless steels are included in the discussion. 200 references

  4. Intratracheally administered pathogen-associated molecular patterns affect antibody responses of poultry.

    Science.gov (United States)

    Ploegaert, T C W; De Vries Reilingh, G; Nieuwland, M G B; Lammers, A; Savelkoul, H F J; Parmentier, H K

    2007-08-01

    Various potential immune-modulating microbially derived pathogen-associated molecular patterns (PAMP), or so called homotopes, are present in high concentrations in the environment of food animals. In previous studies, intravenously administered PAMP had variable effects on specific primary and secondary immune responses of poultry to systemically administered antigens. In the present study, we evaluated the effects of intratracheal (i.t.) challenge with the PAMP lipopolysaccharide, lipoteichoic acid (LTA), and Zymosan-A (containing 1,3 beta-glucan) on primary and secondary (total) antibody (Ab) responses and (isotype) IgM, IgG, and IgA responses to systemically administered human serum albumin (HuSA), and Ab titers to infectious bursal disease (Gumboro virus) and infectious bronchitis vaccines in layer hens at 9 and 22 wk of age. Birds were challenged via the trachea with PAMP for 5 consecutive days prior to primary and secondary immunization with HuSA. Intratracheally administered LTA and, to a minor extent, lipopolysaccharide significantly enhanced secondary total and IgG Ab responses to HuSA. 1,3 beta-Glucan did not significantly affect Ab responses to HuSA. All birds challenged with PAMP showed a decreased BW. Higher total Ab titers to infectious bursal disease and infectious bronchitis were found in birds challenged with LTA. The present results indicate that i.t. administered PAMP affect the humoral immune responsiveness of poultry, which may lead to an enhanced status of immune reactivity. Furthermore, our results suggest that the hygienic status of the environment influences BW (gain). The consequences of immune modulation by airborne PAMP or hygienic conditions in chicken husbandry for vaccine delivery and immune responsiveness of poultry are discussed.

  5. Stainless super p-branes

    International Nuclear Information System (INIS)

    Lue, H.; Pope, C.N.; Sezgin, E.; Stelle, K.S.

    1995-01-01

    The elementary and solitonic supersymmetric p-brane solutions to supergravity theories form families related by dimensional reduction, each headed by a maximal ('stainless') member that cannot be isotropically dimensionally oxidized into higher dimensions. We find several new families, headed by stainless solutions in various dimensions D≤9. In some cases, these occur with dimensions (D,p) that coincide with those of descendants of known families, but since the new solutions are stainless, they are necessarily distinct. The new stainless supersymmetric solutions include a 6-brane and a 5-brane in D=9, a string in D=5, and particles in all dimensions 5≤D≤9. (orig.)

  6. Current recommendations for bladder instillation therapy in the treatment of interstitial cystitis/bladder pain syndrome.

    Science.gov (United States)

    Colaco, Marc A; Evans, Robert J

    2013-10-01

    Bladder instillation therapy refers to the direct introduction of medication into the bladder and is a common treatment modality for patients with interstitial cystitis/bladder pain syndrome (IC/BPS) who have failed conservative and oral therapies. The current American Urological Association (AUA) recommendations list three medications as options for IC/BPS instillation therapy: dimethyl sulfoxide, heparin, and lidocaine. The purpose of this review is to examine the evidence behind the recommendations for these medications. We also examine several historical or experimental therapies that do not hold recommendations but are still used on rare occasion. Finally, we discuss our bladder instillation strategies as well as potential future research and development in intravesicular therapy.

  7. Intratracheal transplantation of endothelial progenitor cells attenuates smoking-induced COPD in mice

    Directory of Open Access Journals (Sweden)

    Shi Z

    2017-03-01

    Full Text Available Zhihui Shi,1 Yan Chen,1 Jun Cao,2 Huihui Zeng,1 Yue Yang,1 Ping Chen,1 Hong Luo,1 Hong Peng,1 Shan Cai,1 Chaxiang Guan3 1Department of Internal Medicine, Division of Respiratory Disease, The Second Xiangya Hospital, Central-South University, 2Department of Internal Medicine, Division of Respiratory Disease, The People’s Hospital of Hunan Province, 3Department of Physiology, Xiangya Medical School, Central-South University, Changsha, Hunan, People’s Republic of China Background: Endothelial progenitor cells (EPCs might play a protective role in COPD. The aim of this study was to investigate whether intratracheal allogeneic transplantation of bone-marrow-derived EPCs would attenuate the development of smoking-induced COPD in mice.Methods: Isolated mononuclear cells from the bone marrow of C57BL/6J mice were cultured in endothelial cell growth medium-2 for 10 days, yielding EPCs. A murine model of COPD was established by passive 90-day exposure of cigarette smoke. On day 30, EPCs or phosphate-buffered saline alone was administered into the trachea. On day 90, EPCs or 30 µL phosphate-buffered saline alone was administered into the trachea, and on day 120, inflammatory cells, antioxidant activity, apoptosis, matrix metalloproteinase (MMP-2, and MMP-9 were measured.Results: After EPC treatment, the lung function of the mice had improved compared with the untreated mice. Mean linear intercept and destructive index were reduced in the EPCs-treated group compared with the untreated group. In addition, the EPCs-treated mice exhibited less antioxidant activity in bronchoalveolar lavage fluid compared with the untreated mice. Moreover, decreased activities of MMP-2, MMP-9, and TUNEL-positive cells in lung tissues were detected in EPCs-treated mice.Conclusion: Intratracheal transplantation of EPCs attenuated the development of pulmonary emphysema and lung function disorder probably by alleviating inflammatory infiltration, decelerating apoptosis

  8. Intranasal H5N1 vaccines, adjuvanted with chitosan derivatives, protect ferrets against highly pathogenic influenza intranasal and intratracheal challenge.

    Directory of Open Access Journals (Sweden)

    Alex J Mann

    Full Text Available We investigated the protective efficacy of two intranasal chitosan (CSN and TM-CSN adjuvanted H5N1 Influenza vaccines against highly pathogenic avian Influenza (HPAI intratracheal and intranasal challenge in a ferret model. Six groups of 6 ferrets were intranasally vaccinated twice, 21 days apart, with either placebo, antigen alone, CSN adjuvanted antigen, or TM-CSN adjuvanted antigen. Homologous and intra-subtypic antibody cross-reacting responses were assessed. Ferrets were inoculated intratracheally (all treatments or intranasally (CSN adjuvanted and placebo treatments only with clade 1 HPAI A/Vietnam/1194/2004 (H5N1 virus 28 days after the second vaccination and subsequently monitored for morbidity and mortality outcomes. Clinical signs were assessed and nasal as well as throat swabs were taken daily for virology. Samples of lung tissue, nasal turbinates, brain, and olfactory bulb were analysed for the presence of virus and examined for histolopathological findings. In contrast to animals vaccinated with antigen alone, the CSN and TM-CSN adjuvanted vaccines induced high levels of antibodies, protected ferrets from death, reduced viral replication and abrogated disease after intratracheal challenge, and in the case of CSN after intranasal challenge. In particular, the TM-CSN adjuvanted vaccine was highly effective at eliciting protective immunity from intratracheal challenge; serologically, protective titres were demonstrable after one vaccination. The 2-dose schedule with TM-CSN vaccine also induced cross-reactive antibodies to clade 2.1 and 2.2 H5N1 viruses. Furthermore ferrets immunised with TM-CSN had no detectable virus in the respiratory tract or brain, whereas there were signs of virus in the throat and lungs, albeit at significantly reduced levels, in CSN vaccinated animals. This study demonstrated for the first time that CSN and in particular TM-CSN adjuvanted intranasal vaccines have the potential to protect against significant

  9. Protective Effects of Intratracheally-Administered Bee Venom Phospholipase A2 on Ovalbumin-Induced Allergic Asthma in Mice

    Directory of Open Access Journals (Sweden)

    Kyung-Hwa Jung

    2016-09-01

    Full Text Available Asthma is a common chronic disease characterized by bronchial inflammation, reversible airway obstruction, and airway hyperresponsiveness (AHR. Current therapeutic options for the management of asthma include inhaled corticosteroids and β2 agonists, which elicit harmful side effects. In the present study, we examined the capacity of phospholipase A2 (PLA2, one of the major components of bee venom (BV, to reduce airway inflammation and improve lung function in an experimental model of asthma. Allergic asthma was induced in female BALB/c mice by intraperitoneal administration of ovalbumin (OVA on days 0 and 14, followed by intratracheal challenge with 1% OVA six times between days 22 and 30. The infiltration of immune cells, such as Th2 cytokines in the lungs, and the lung histology, were assessed in the OVA-challenged mice in the presence and absence of an intratracheal administration of bvPLA2. We showed that the intratracheal administration of bvPLA2 markedly suppressed the OVA-induced allergic airway inflammation by reducing AHR, overall area of inflammation, and goblet cell hyperplasia. Furthermore, the suppression was associated with a significant decrease in the production of Th2 cytokines, such as IL-4, IL-5, and IL-13, and a reduction in the number of total cells, including eosinophils, macrophages, and neutrophils in the airway.

  10. Intratracheal co-administration of antioxidants and ceftriaxone reduces pulmonary injury and mortality rate in an experimental model of sepsis.

    Science.gov (United States)

    Galvão, Andre M; Wanderley, Marcela S O; Silva, Roberto A; Filho, Carlos A M; Melo-Junior, Mário R; Silva, Luciano A; Streck, Emílio L; Dornelas de Andrade, Armele F; Souza Maia, Maria B; Barbosa de Castro, Celia M M

    2014-10-01

    Recent studies showed that both sepsis and antibiotic therapy are associated with cell death and linked to reactive oxygen species generation. This study investigated the effects of intratracheal administration of combinations of antioxidants (n-acetyl cysteine (NAC), vitamins C and E) in the treatment of sepsis-induced lung injury. Ninety-six male Wistar rats subjected to sepsis were treated with ceftriaxone plus NAC with or without vitamins C and E and compared to appropriate controls. As an index of oxidative damage protein carbonyls, sulfhydryl groups, lipid peroxidation and superoxide anion were measured, as well as superoxide dismutase and catalase. Histopathological alterations and mortality rate were also analyzed. Twenty-four hours after sepsis induction, markers of oxidative stress increased in all lungs examined. Ceftriaxone plus intratracheal combination of NAC, vitamins C and E decreased lung injury in infected animals by reducing superoxide anion production (54%), lipid peroxidation (53%) and protein carbonyl (58%) and restored the redox status (7.5 times). This therapy also reduced the imbalance of antioxidant enzymes activities and attenuated the alveolar architectural disorganization, inflammatory cell infiltration and pulmonary oedema. Survival increased from 66.6% with ceftriaxone to 83.2% with ceftriaxone plus antioxidants. Ceftriaxone plus intratracheal co-administration of antioxidants provides better protection, by decreasing pulmonary oxidative stress, limiting histophatological alterations and improving survival. Antioxidants should be explored as a co-adjuvant in the treatment of severe lung injury. © 2014 Asian Pacific Society of Respirology.

  11. Vitamin A is systemically bioavailable after intratracheal administration with surfactant in an animal model of newborn respiratory distress.

    Science.gov (United States)

    Singh, Avash J; Bronshtein, Vadim; Khashu, Minesh; Lee, Kyle; Potts, James E; Friel, James; Chessex, Philippe

    2010-06-01

    Chronic lung disease (CLD) is a major cause of long-term morbidity in extremely LBW infants with respiratory distress syndrome. Parenteral vitamin A administration decreases the risk of CLD. We tested the hypothesis that intratracheal vitamin A administration with surfactant is systemically bioavailable without interfering with the functional properties of exogenous surfactant. Newborn piglets were ventilated with 100% FiO2 and sequential saline lavage induced respiratory distress syndrome. During lung injury induction, ventilator changes were allowed, but none were made following treatment allocation. Animals were assigned by chance in a blinded control trial to three groups: I=control; II=surfactant; III=surfactant+vitamin A. Hemodynamics, lung mechanics, and blood gases were measured following instrumentation, pre- and posttreatment for 4 h, at which time the liver was sampled for retinol determination. All parameters improved in animals receiving surfactant. A significant interaction existed between time and group for PaO2 and alveolar-arterial oxygen difference (A-aDO2). Hepatic levels of retinol were higher (p<0.001) in animals receiving retinyl acetate. Intratracheal administration of surfactant+vitamin A did not alter the beneficial effects of surfactant on lung compliance and gas exchange. Intratracheal Vitamin A was associated with rapid hepatic uptake. Further studies are warranted.

  12. Intratracheal administration of fullerene nanoparticles activates splenic CD11b{sup +} cells

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Ning [Department of Immunology and Parasitology, School of Medicine, University of Occupational and Environmental Health, Japan, 1-1 Iseigaoka, Yahata-nishi-ku, Kitakyushu 807-8555 (Japan); Kunugita, Naoki [Department of Environmental Health, National Institute of Public Health, 2-3-6, Minami, Wako 351-0197 (Japan); Ichinose, Takamichi [Department of Health Sciences, Oita University of Nursing and Health Sciences, Oita 870-1201 (Japan); Song, Yuan [Department of Immunology and Parasitology, School of Medicine, University of Occupational and Environmental Health, Japan, 1-1 Iseigaoka, Yahata-nishi-ku, Kitakyushu 807-8555 (Japan); Yokoyama, Mitsuru [Bio-information Research Center, University of Occupational and Environmental Health, Japan, 1-1 Iseigaoka, Yahata-nishi-ku, Kitakyushu 807-8555 (Japan); Arashidani, Keiichi [School of Health Sciences, University of Occupational and Environmental Health, Japan, 1-1 Iseigaoka, Yahata-nishi-ku, Kitakyushu 807-8555 (Japan); Yoshida, Yasuhiro, E-mail: freude@med.uoeh-u.ac.jp [Department of Immunology and Parasitology, School of Medicine, University of Occupational and Environmental Health, Japan, 1-1 Iseigaoka, Yahata-nishi-ku, Kitakyushu 807-8555 (Japan)

    2011-10-30

    Highlights: {yields} Fullerene administration triggered splenic responses. {yields} Splenic responses occurred at different time-points than in the lung tissue. {yields} CD11b{sup +} cells were demonstrated to function as responder cells to fullerene. - Abstract: Fullerene nanoparticles ('Fullerenes'), which are now widely used materials in daily life, have been demonstrated to induce elevated pulmonary inflammation in several animal models; however, the effects of fullerenes on the immune system are not fully understood. In the present study, mice received fullerenes intratracheally and were sacrificed at days 1, 6 and 42. Mice that received fullerenes exhibited increased proliferation of splenocytes and increased splenic production of IL-2 and TNF-{alpha}. Changes in the spleen in response to fullerene treatment occurred at different time-points than in the lung tissue. Furthermore, fullerenes induced CDK2 expression and activated NF-{kappa}B and NFAT in splenocytes at 6 days post-administration. Finally, CD11b{sup +} cells were demonstrated to function as responder cells to fullerene administration in the splenic inflammatory process. Taken together, in addition to the effects on pulmonary responses, fullerenes also modulate the immune system.

  13. Gene expression analysis in rat lungs after intratracheal exposure to nanoparticles doped with cadmium

    Science.gov (United States)

    Coccini, Teresa; Fabbri, Marco; Roda, Elisa; Grazia Sacco, Maria; Manzo, Luigi; Gribaldo, Laura

    2011-07-01

    Silica nanoparticles (NPs) incorporating cadmium (Cd) have been developed for a range of potential application including drug delivery devices. Occupational Cd inhalation has been associated with emphysema, pulmonary fibrosis and lung tumours. Mechanistically, Cd can induce oxidative stress and mediate cell-signalling pathways that are involved in inflammation.This in vivo study aimed at investigating pulmonary molecular effects of NPs doped with Cd (NP-Cd, 1 mg/animal) compared to soluble CdCl2 (400 μg/animal), in Sprague Dawley rats treated intra-tracheally, 7 and 30 days after administration. NPs of silica containing Cd salt were prepared starting from commercial nano-size silica powder (HiSil™ T700 Degussa) with average pore size of 20 nm and surface area of 240 m2/g. Toxicogenomic analysis was performed by the DNA microarray technology (using Agilent Whole Rat Genome Microarray 4×44K) to evaluate changes in gene expression of the entire genome. These findings indicate that the whole genome analysis may represent a valuable approach to assess the whole spectrum of biological responses to cadmium containing nanomaterials.

  14. Gene expression analysis in rat lungs after intratracheal exposure to nanoparticles doped with cadmium

    International Nuclear Information System (INIS)

    Coccini, Teresa; Manzo, Luigi; Fabbri, Marco; Sacco, Maria Grazia; Gribaldo, Laura; Roda, Elisa

    2011-01-01

    Silica nanoparticles (NPs) incorporating cadmium (Cd) have been developed for a range of potential application including drug delivery devices. Occupational Cd inhalation has been associated with emphysema, pulmonary fibrosis and lung tumours. Mechanistically, Cd can induce oxidative stress and mediate cell-signalling pathways that are involved in inflammation.This in vivo study aimed at investigating pulmonary molecular effects of NPs doped with Cd (NP-Cd, 1 mg/animal) compared to soluble CdCl 2 (400 μg/animal), in Sprague Dawley rats treated intra-tracheally, 7 and 30 days after administration. NPs of silica containing Cd salt were prepared starting from commercial nano-size silica powder (HiSil T M T700 Degussa) with average pore size of 20 nm and surface area of 240 m 2 /g. Toxicogenomic analysis was performed by the DNA microarray technology (using Agilent Whole Rat Genome Microarray 4x44K) to evaluate changes in gene expression of the entire genome. These findings indicate that the whole genome analysis may represent a valuable approach to assess the whole spectrum of biological responses to cadmium containing nanomaterials.

  15. Gene expression analysis in rat lungs after intratracheal exposure to nanoparticles doped with cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Coccini, Teresa; Manzo, Luigi [Toxicology Division, Salvatore Maugeri Foundation IRCCS, Pavia (Italy); Fabbri, Marco; Sacco, Maria Grazia; Gribaldo, Laura [European Commission, Joint Research Centre, IHCP- 21027 Ispra (Italy); Roda, Elisa [European Centre for Nanomedicine, University of Pavia, 27100 Pavia (Italy)

    2011-07-06

    Silica nanoparticles (NPs) incorporating cadmium (Cd) have been developed for a range of potential application including drug delivery devices. Occupational Cd inhalation has been associated with emphysema, pulmonary fibrosis and lung tumours. Mechanistically, Cd can induce oxidative stress and mediate cell-signalling pathways that are involved in inflammation.This in vivo study aimed at investigating pulmonary molecular effects of NPs doped with Cd (NP-Cd, 1 mg/animal) compared to soluble CdCl{sub 2} (400 {mu}g/animal), in Sprague Dawley rats treated intra-tracheally, 7 and 30 days after administration. NPs of silica containing Cd salt were prepared starting from commercial nano-size silica powder (HiSil{sup TM} T700 Degussa) with average pore size of 20 nm and surface area of 240 m{sup 2}/g. Toxicogenomic analysis was performed by the DNA microarray technology (using Agilent Whole Rat Genome Microarray 4x44K) to evaluate changes in gene expression of the entire genome. These findings indicate that the whole genome analysis may represent a valuable approach to assess the whole spectrum of biological responses to cadmium containing nanomaterials.

  16. Intratracheal administration of fullerene nanoparticles activates splenic CD11b+ cells

    International Nuclear Information System (INIS)

    Ding, Ning; Kunugita, Naoki; Ichinose, Takamichi; Song, Yuan; Yokoyama, Mitsuru; Arashidani, Keiichi; Yoshida, Yasuhiro

    2011-01-01

    Highlights: → Fullerene administration triggered splenic responses. → Splenic responses occurred at different time-points than in the lung tissue. → CD11b + cells were demonstrated to function as responder cells to fullerene. - Abstract: Fullerene nanoparticles ('Fullerenes'), which are now widely used materials in daily life, have been demonstrated to induce elevated pulmonary inflammation in several animal models; however, the effects of fullerenes on the immune system are not fully understood. In the present study, mice received fullerenes intratracheally and were sacrificed at days 1, 6 and 42. Mice that received fullerenes exhibited increased proliferation of splenocytes and increased splenic production of IL-2 and TNF-α. Changes in the spleen in response to fullerene treatment occurred at different time-points than in the lung tissue. Furthermore, fullerenes induced CDK2 expression and activated NF-κB and NFAT in splenocytes at 6 days post-administration. Finally, CD11b + cells were demonstrated to function as responder cells to fullerene administration in the splenic inflammatory process. Taken together, in addition to the effects on pulmonary responses, fullerenes also modulate the immune system.

  17. Intravesical instillation of Formalin for hemorrhagic cystitis secondary to radiation for gynecologic malignancies

    International Nuclear Information System (INIS)

    Behnam, K.; Patil, U.B.; Mariano, E.

    1983-01-01

    Our experience with the use of Formalin instillation in intractable gross hematuria secondary to radiation cystitis in patients with gynecological malignancies is reported. This study indicates coagulative effect of low concentration of Formalin with minimal side effects as a method to control hemorrhage

  18. Intraperitoneal instillation of saline and local anesthesia for prevention of shoulder pain after laparoscopic cholecystectomy

    DEFF Research Database (Denmark)

    Donatsky, Anders Meller; Bjerrum, Flemming; Gögenür, Ismayil

    2013-01-01

    instillation (IPI) of saline and local anesthesia (LA) to minimize SP. METHODS: A search of the literature was conducted using PubMed and Excerpta Medica Database (EMBASE). Eligibility criteria were: randomized clinical trials (RCT) evaluating IPI of saline and/or LA to minimize incidence or severity of SP...

  19. Prophylactic yttrium 90 instillation in the case of bladder carcinomas Jewett 0

    International Nuclear Information System (INIS)

    Donn, F.; Becker, H.; Kaufmann, J.; Montz, H.R.

    1982-01-01

    We performed in a prospective pilot study the treatment of bladder cancer Jewett 0 by 90-Yttrium-instillation. The chief aim is to prevent recurrent tumour formation. Our technique delivers an average dose of ca. 3000 rad to the surface of the bladder. The complication rate was moderate. The results were encouraging because the recurrent tumour formation was distinctly reduced. (orig.) [de

  20. Gentamicin bladder instillations decrease symptomatic urinary tract infections in neurogenic bladder patients on intermittent catheterization.

    Science.gov (United States)

    Cox, Lindsey; He, Chang; Bevins, Jack; Clemens, J Quentin; Stoffel, John T; Cameron, Anne P

    2017-09-01

    This study aimed to determine if gentamicin bladder instillations reduce the rate of symptomatic urinary tract infection (UTI) in neurogenic bladder (NGB) patients on intermittent self-catheterization (ISC) who have recurrent UTIs. Secondary aims were to examine the effects of intravesical gentamicin on the organism resistance patterns. We retrospectively reviewed our prospective NGB database. Inclusion criteria were NGB patients performing ISC exclusively for bladder drainage with clinical data available for six months before and six months after initiating prophylactic intravesical gentamicin instillations. Symptomatic UTIs were defined as symptoms consistent with UTI plus the need for antibiotic treatment. Twenty-two patients met inclusion criteria; etiology of NGB was 63.6% spinal cord injury, 13.6% multiple sclerosis. Median time since injury/diagnosis was 14 years and 6/22 (27.3%) had undergone urological reconstruction. Patients had fewer symptomatic UTI's (median 4 vs. 1 episodes; pbladder instillations decrease symptomatic UTI episodes and reduce oral antibiotics in patients with NGB on ISC who were suffering from recurrent UTIs. Antibiotic resistance decreased while on gentamicin instillations.

  1. [Our experience with 1 mg BCG vaccine instillation in T1 stage cancer of the bladder].

    Science.gov (United States)

    Rivera, P; Orio, M; Hinostroza, J; Venegas, P; Pastor, P; Gorena, M; Lagos, M; Pinochet, R

    1999-10-01

    We studied 67 patients with bladder cancer in stage T1, with terminated BCG treatment and in pursuit. No stage Ta neither carcinoma in situ was included. The protocol was: beginning of treatment upon retiring vesical catheter, instilation of 1 mg of liofilized BCG vaccine (16 x 10(6) bacilles) in 40-50 ml of intravesical saline solution. A weekly instilation during the first month. An instilation each 15 days during the second and third month and one monthly until complete 12 months of treatment. Also was carried out an study of T lymphocites and cytokines. The average followup of the 67 patients treated was 51.3 months. 17 patients relapses (25.4%). A 33% were grade 3 and 27% grade 2. Like complications there was a case of inguinal TBC adenititis, 2 TBC prostatitis, 2 TBC cistitis and 5 cases of slight disuric syndrome. The study of subpopulations of lymphocites in peripheral blood demonstrated a significant increase of CD3 and CD4/CD8 ratio. The interleukin 2 measurement in serum also increased significantly after the BCG instilations. Our protocol gets similar results to the higher doses, but with minimal complications diminishing the relapses of the tumors in stage T1. A monthly maintenance dose would help to maintain immunity.

  2. Extracellular matrix alterations after blood instillation in tunica albuginea of rats.

    Science.gov (United States)

    Cohen, David J; Oliveira, André V; Theodoro, Théresè R; Petri, Giuliana; Melo, Carina M; Cavalheiro, Renan P; Nader, Helena B; Mader, Ana M; Pinhal, Maria A S; Glina, Sidney

    2017-12-15

    The cause of Peyronie's disease (PD) is still not completely understood. The objective of this study, therefore, was to analyze the histological and biochemical alterations that occur after the instillation of blood in the tunica albuginea (TA) of rats with an emphasis on the remodeling process of ECM. Thirty male Wistar rats were divided into 4 groups: two control groups with instillation of distilled water in TA followed by penectomy after 15 days or 45 days, respectively and two experimental groups with instillation of blood in TA followed by penectomy after 15 days or 45 days, respectively. Histological, immunofluorescent and immunohistochemical analyses were performed. The higher presence of fibrotic tissue in rats injected with blood demonstrated alterations in TA similar to inflammation found in PD. The increased expression of TGF-β, MMP9, HPSE, and biglycan associated with the decreased expression of syndecan-1 and aggrecan in the experimental groups suggested an enhancement in the remodeling of ECM. The results contribute to show that blood instillation on TA appears to trigger alterations in the ECM similar to the ones found in inflammatory diseases such as PD.

  3. Distribution assessment comparing continuous and periodic wound instillation in conjunction with negative pressure wound therapy using an agar-based model.

    Science.gov (United States)

    Rycerz, Anthony M; Slack, Paul; McNulty, Amy K

    2013-04-01

    Negative pressure wound therapy (NPWT) is a widely accepted and effective treatment for various wound types, including complex wounds. Negative pressure with instillation was initially used as a gravity-fed system whereby reticulated, open-cell foam in the wound bed was periodically exposed to cycles of soaking with instillation solution followed by NPWT. Recent publications have alluded to positive outcomes with continuous instillation, where fluid is delivered simultaneously with negative pressure. To evaluate the distribution of instillation solutions to wound beds in conjunction with negative pressure, agar-based models were developed and exposed to coloured instillation solutions to identify exposure intensity via agar staining. This model allowed comparison of continuous- versus periodic-instillation therapy with negative pressure. Continuous instillation at a rate of 30 cc/hour with negative pressure showed isolated exposure of instillation fluid to wound beds in agar wound models with and without undermining and tunnelling. In contrast, periodic instillation illustrated uniform exposure of the additive to the entire wound bed including undermined and tunnel areas, with increased staining with each instillation cycle. These findings suggest that periodic instillation facilitates more uniform exposure throughout the wound, including tunnels and undermining, to instillation solutions, thereby providing therapy consistent with the clinician-ordered treatment. © 2012 The Authors. International Wound Journal © 2012 Blackwell Publishing Ltd and Medicalhelplines.com Inc.

  4. Pharmacokinetic/Pharmacodynamic Profiles of Tiamulin in an Experimental Intratracheal Infection Model of Mycoplasma gallisepticum

    Directory of Open Access Journals (Sweden)

    Xia Xiao

    2016-09-01

    Full Text Available Mycoplasma gallisepticum is the most important pathogen in poultry among four pathogenic Mycoplasma species. Tiamulin is a pleuromutilin antibiotic that shows a great activity against M. gallisepticum and has been approved for use in veterinary medicine particularly for poultry. However, the Pharmacokinetic/Pharmacodynamics (PK/PD profiles of tiamulin against M. gallisepticum are not well understood. Therefore, in the current studies, we investigated the in vivo PK/PD profiles of tiamulin using a well-established experimental intratracheal infection model of M. gallisepticum. The efficacy of tiamulin against M. gallisepticum was studied in 8-day-old chickens after intramuscular (i.m. administration at 10 doses between 0-80 mg/kg. Liquid chromatography-tandem mass spectrometry (LC-MS/MS was used to evaluate the PK parameters of tiamulin following i.m. administration at doses of 5, 40 and 80 mg/kg in Mycoplasma gallisepticum infected neutropenic chickens. Real time PCR (RT-PCR was used for quantitative detection of M. gallisepticum. The MIC of tiamulin against M. gallisepticum strain S6 was 0.03 μg/mL. The PK/PD index, AUC24h/MIC, correlated well with the in vivo antibacterial efficacy. The in vivo data suggest that animal dosage regimens should supply AUC24h/MIC of tiamulin of 382.68 h for 2 log10 ccu equivalents M. gallisepticum reduction. To attain that goal, the administered dose is expected to be 45 mg/kg b.w. for treatment of M. gallisepticum infection with an MIC90 of 0.03 μg/mL.

  5. Intratracheal infection as an efficient route for testing vaccines against Chlamydia abortus in sheep.

    Science.gov (United States)

    Álvarez, D; Salinas, J; Buendía, A J; Ortega, N; del Río, L; Sánchez, J; Navarro, J A; Gallego, M C; Murcia-Belmonte, A; Cuello, F; Caro, M R

    2015-09-01

    Pregnant ewes have been widely used to test vaccines against Chlamydia abortus. However, this model entails many disadvantages such as high economic costs and long periods of pregnancy. The murine model is very useful for specific studies but cannot replace the natural host for the later stages of vaccine evaluation. Therefore, a non-pregnant model of the natural host might be useful for a vaccine trial to select the best vaccine candidates prior to use of the pregnant model. With this aim, two routes of infection were assessed in young non-pregnant sheep, namely, intranasal (IN) and intratracheal (IT). In addition, groups of non-vaccinated sheep and sheep immunised with an inactivated vaccine were established to investigate the suitability of the model for testing vaccines. After the experimental infection, isolation of the microorganism in several organs, with pathological and immunohistochemical analyses, antibody production assessment and investigation by PCR of the presence of chlamydia in the vagina or rectum were carried out. Experimental IT inoculation of C. abortus induced pneumonia in sheep during the first few days post-infection, confirming the suitability of the IT route for testing vaccines in the natural host. The course of infection and the resulting pathological signs were less severe in vaccinated sheep compared with non-vaccinated animals, demonstrating the success of vaccination. IN infection did not produce evident lesions or demonstrate the presence of chlamydial antigen in the lungs and cannot be considered an appropriate model for testing vaccines. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Comparison of Three Different Administration Positions for Intratracheal Beractant in Preterm Newborns with Respiratory Distress Syndrome.

    Science.gov (United States)

    Karadag, Ahmet; Ozdemir, Ramazan; Degirmencioglu, Halil; Uras, Nurdan; Dilmen, Ugur; Bilgili, Gokmen; Erdeve, Omer; Cakir, Ufuk; Atasay, Begum

    2016-04-01

    The aim of this study was to compare the efficacy and adverse effects of various intratracheal beractant administration positions in preterm newborns with respiratory distress syndrome. This study was performed on preterm newborns with respiratory distress syndrome. The inclusion criteria were being between 26 weeks and 32 weeks of gestational age, having a birth weight between 600 g and 1500 g, having received clinical and radiological confirmation for the diagnosis of respiratory distress syndrome (RDS) within 3 hours of life, having been born in one of the centers where the study was carried out, and having fractions of inspired oxygen (FiO2) ≥ 0.40 to maintain oxygen saturation by pulse oximeter at 88-96%. Beractant was administered in four positions to Group I newborns, in two positions to Group II, and in neutral position to Group III. Groups I and II consisted of 42 preterm infants in each whereas Group III included 41 preterm infants. No significant differences were detected among the groups with regards to maternal and neonatal risk factors. Groups were also similar in terms of the following complications: patent ductus arteriosus (PDA), pneumothorax, intraventricular hemorrhage (IVH), chronic lung disease (CLD), retinopathy of prematurity (ROP), necrotising enterocolitis (NEC), death within the first 3 days of life, death within the first 28 days of life, and rehospitalization within 1 month after discharge. Neither any statistically significant differences among the parameters related with surfactant administration, nor any significant statistical differences among the FiO2 levels and the saturation levels before and after the first surfactant administration among the groups were determined. In terms of efficacy and side effects, no important difference was observed between the recommended four position beractant application, the two position administration, and the neutral position. Copyright © 2016. Published by Elsevier B.V.

  7. Visualization of murine intranasal dosing efficiency using luminescent Francisella tularensis: effect of instillation volume and form of anesthesia.

    Directory of Open Access Journals (Sweden)

    Mark A Miller

    Full Text Available Intranasal instillation is a widely used procedure for pneumonic delivery of drugs, vaccine candidates, or infectious agents into the respiratory tract of research mice. However, there is a paucity of published literature describing the efficiency of this delivery technique. In this report we have used the murine model of tularemia, with Francisella tularensis live vaccine strain (FTLVS infection, to evaluate the efficiency of pneumonic delivery via intranasal dosing performed either with differing instillation volumes or different types of anesthesia. FTLVS was rendered luminescent via transformation with a reporter plasmid that constitutively expressed the Photorhabdus luminescens lux operon from a Francisella promoter. We then used an IVIS Spectrum whole animal imaging system to visualize FT dissemination at various time points following intranasal instillation. We found that instillation of FT in a dose volume of 10 µl routinely resulted in infection of the upper airways but failed to initiate infection of the pulmonary compartment. Efficient delivery of FT into the lungs via intranasal instillation required a dose volume of 50 µl or more. These studies also demonstrated that intranasal instillation was significantly more efficient for pneumonic delivery of FTLVS in mice that had been anesthetized with inhaled (isoflurane vs. parenteral (ketamine/xylazine anesthesia. The collective results underscore the need for researchers to consider both the dose volume and the anesthesia type when either performing pneumonic delivery via intranasal instillation, or when comparing studies that employed this technique.

  8. On- and post-treatment symptom relief by repeated instillations of heparin and alkalized lidocaine in interstitial cystitis.

    Science.gov (United States)

    Nomiya, Akira; Naruse, Takashi; Niimi, Aya; Nishimatsu, Hiroaki; Kume, Haruki; Igawa, Yasuhiko; Homma, Yukio

    2013-11-01

    To examine outcomes of intravesical instillations of heparin and alkalized lidocaine in patients with interstitial cystitis. Patients with interstitial cystitis refractory to conventional therapies were given a solution of 20 000 U heparin, 5 mL 4% lidocaine and 25 mL 7% sodium bicarbonate, intravesically, weekly for 12 weeks consecutively. The treatment was regarded as "effective", when patients rated "slightly improved" or "better" on a seven-graded scale of global response assessment. Other assessment measures included O'Leary and Sant's symptom index and problem index, visual analog scale for pain, and frequency volume chart variables. A total of 32 patients were enrolled in the study. The average age was 63.3 years. All participants had received hydrodistension 2.2 times on average, and fulfilled National Institute of Diabetes and Digestive and Kidney Diseases criteria. The therapy was effective in 60.0% of the patients at the fourth instillation, in 76.7% at the last instillation, and 90.0%, 46.7% and 16.7% at 1, 2 and 6 months after the last instillation, respectively. Most of other assessment measures improved significantly at the fourth instillation and further beyond until the end of therapy. On termination of therapy, the efficacy gradually diminished, yet mostly maintained statistical significance by 2 months post-instillation. No severe adverse events occurred. A 12-week course of weekly intravesical instillations of heparin combined with alkalized lidocaine is safe and effective in relieving symptoms in interstitial cystitis patients. The effect of the treatment is maintained for 6 months. Further studies are required to optimize the number of instillations and maintenance intervals in order to maximize the therapeutic potential of simple or combined instillations in the management of interstitial cystitis. © 2013 The Japanese Urological Association.

  9. Intratracheal atomized surfactant provides similar outcomes as bolus surfactant in preterm lambs with respiratory distress syndrome.

    Science.gov (United States)

    Milesi, Ilaria; Tingay, David G; Zannin, Emanuela; Bianco, Federico; Tagliabue, Paolo; Mosca, Fabio; Lavizzari, Anna; Ventura, Maria Luisa; Zonneveld, C Elroy; Perkins, Elizabeth J; Black, Don; Sourial, Magdy; Dellacá, Raffaele L

    2016-07-01

    Aerosolization of exogenous surfactant remains a challenge. This study is aimed to evaluate the efficacy of atomized poractant alfa (Curosurf) administered with a novel atomizer in preterm lambs with respiratory distress syndrome. Twenty anaesthetized lambs, 127 ± 1 d gestational age, (mean ± SD) were instrumented before birth and randomized to receive either (i) positive pressure ventilation without surfactant (Control group), (ii) 200 mg/kg of bolus instilled surfactant (Bolus group) at 10 min of life or (iii) 200 mg/kg of atomized surfactant (Atomizer group) over 60 min from 10 min of life. All lambs were ventilated for 180 min with a standardized protocol. Lung mechanics, regional lung compliance (electrical impedance tomography), and carotid blood flow (CBF) were measured with arterial blood gas analysis. Dynamic compliance and oxygenation responses were similar in the Bolus and Atomizer groups, and both better than Control by 180 min (all P < 0.05; two-way ANOVA). Both surfactant groups demonstrated more homogeneous regional lung compliance throughout the study period. There were no differences in CBFConclusion:In a preterm lamb model, atomized surfactant resulted in similar gas exchange and mechanics as bolus administration. This study suggests evaluation of supraglottic atomization with this system when noninvasive support is warranted.

  10. [Negative Pressure Wound Therapy with Instillation in the Treatment of Critical Wounds].

    Science.gov (United States)

    Gathen, M; Petri, M; Krettek, C; Omar, M

    2016-04-01

    In recent decades, negative pressure wound therapy (NPWT) has become the gold standard in the treatment of infected wounds. Negative pressure wound therapy with instillation (NPWTi) is a new development, that combines conventional NPWT with instillation of fluids. The purpose of this study was to review the results of current literature on the clinical use of NPWTi in acute and chronic wounds. A literature search was performed using Pubmed and the Cochrane Library, including articles in English and German. The data suggest that NPWTi is a promising therapeutic option in the treatment of wounds, and applicable in various fields. NPWTi appears to be a useful adjunct in the treatment of critical wounds. However, data from prospective randomised trials to support the validity of the results are sparse. Georg Thieme Verlag KG Stuttgart · New York.

  11. Hemostasis in acquired hemophilia--role of intracavitary instillation of EACA.

    Directory of Open Access Journals (Sweden)

    Sahu S

    1996-07-01

    Full Text Available An 82 year old man developed antibodies against coagulation factor VIII:C without any apparent cause. Bleeding from the soft tissue cavity could not be controlled by factor VIII:C concentrates, immunosuppression with steroids and intravenous immunoglobulin therapy in the standard dosages. However, a single injection of Epsilon Aminocaproic Acid (EACA instilled into the cavity under aseptic precautions achieved lasting hemostasis with resultant wound healing.

  12. The effect of wound instillation of a novel purified capsaicin formulation on postherniotomy pain

    DEFF Research Database (Denmark)

    Aasvang, Eske K; Hansen, Jeanette B; Malmstrøm, Jørgen

    2008-01-01

    , preclinical, and clinical studies, and may be an effective adjunct to postoperative pain management. METHODS: We performed a single-center, randomized, double-blind, placebo-controlled study of the analgesic efficacy of a single intraoperative wound instillation of 1000 microg ultrapurified capsaicin (ALGRX.......05), but not for the whole 1 or 4 wk postoperatively. Mixed-effects analysis with NONMEM revealed that pain scores were significantly lower (P observed, although a mild transient increase in liver enzymes was seen...

  13. A pharmacoeconomic analysis of the use of single MMC instillation in low risk NMIBC in Italy

    Directory of Open Access Journals (Sweden)

    Renzo Colombo

    2013-03-01

    Full Text Available BACKGROUND: Bladder cancer accounts for 5-10% of all cancers in Europe and up to 85% patients presents a noninvasive tumor, whose treatment of choice is the transurethral bladder resection (TURB paired with adjuvant intravesical chemotherapy or immunotherapy. Despite several clinical trials showed that this treatment is safe and decreases recurrences by 17% to 44% this practice is limited for many reasons. The study objective is to analyze the economical advantages of the single immediate post operative Mitomycin C instillation in Non Muscle-invasive Bladder Cancer (NMIBC low-risk patients.METHODS: A cost-benefit analysis was performed evaluating the economical gain that would raised from a scenario with a single immediate post operative mitomycin C instillation in each low-risk NMIBC patient who underwent to TURB. Net present value and cost-benefit ratio were calculated and sensitivity analyses were performed. Base case analysis was performed considering tumor recurrence rate reduction of 11.7% and a TURB costs of 2,167.0 €, while sensitivity analyses were performed using a recurrence rate reduction of 19.2% and 15.0% and a TURB cost of 2,472.93 €. The discount rate was 2%.RESULTS: The single immediate post operative instillation of mitomycin C resulted to be cost-beneficial with a cost-benefit ratio that goes from 0.48 to 0.79 when compared to TURB alone raising a Net Present Value that goes from 660,284.39 € to 2,650,530.79 €.CONCLUSION: This study demonstrates that even assuming conservative parameters for recurrence rates reduction, a single immediate post operative mitomycin C instillation in low risk NMIBC patients would lower not only the recurrence rate but also the caring cost for bladder cancer.

  14. Retrograde Instillation of Methylene Blue in the Difficult Diagnosis of BPF

    Directory of Open Access Journals (Sweden)

    F. Ravenna

    2012-01-01

    Full Text Available We report two cases in which we were able to diagnose bronchopleural fistula through retrograde methylene blue instillation during bronchoscopy. In the first case, methylene blue was injected through an abdominal drain, followed by air instillation and detected in the left bronchial tree, demonstrating the presence of a fistula in the lingula’s bronchus. In the second case, methylene blue was injected into a pleural drain, through a breach on a surgical suture and detected in the right bronchial tree, demonstrating the presence of a fistula in the right inferior bronchus. The retrograde instillation of methylene blue, through a drain in the abdomen or the thoracic wall, is a safe, cheap, and practical method that allows the bronchoscopist to identify the presence of a fistula and, more importantly, to identify the exact point on the bronchial tree where a fistula is located. This provides the possibility of sealing the fistula with a variety of devices. It is our opinion that this procedure should be considered a primary method of diagnosis when a bronchopleural fistula is suspected and a drain on the thoracic or abdominal wall is positioned such that effusions are able to drain.

  15. Steroid instillation for idiopathic urethritis in children: an 8-year experience.

    Science.gov (United States)

    Jayakumar, Sivasankar; Ninan, George Kaithayil; Pringle, Kirsty

    2015-04-01

    Idiopathic urethritis (IU) in children is of unknown etiology and treatment options are limited. We aim to report our experience with steroid instillation in IU in children. Retrospective data collection of all male children diagnosed with IU over a period of 8 years. Patients with balanitis xerotica obliterans (BXO) and positive urine culture at presentation were excluded from the study. Data were collected on patient demographics, laboratory and radiological investigations, cystoscopy findings, management, and outcomes. A total of 16 male children were diagnosed with IU. The mean age was 11.6 (7-16) years. Presenting symptoms included dysuria in 10; frank hematuria in 7; loin pain in 5; and scrotal pain in 2 patients. Serum C-reactive protein and full blood count was tested in 13 patients and was within normal limits in all of them. Endoscopy findings included posterior urethritis in 12, anterior urethritis in 2, and urethral stricture with inflammation in 2 patients. Ten patients required more than one episode of steroid instillation. Mean follow-up was 19.4 (1-74) months. Complete resolution of symptoms and signs occurred in 15 (93.6%) patients and improvement of symptoms and signs noted with ongoing treatment in 1 (6.4%) patient. IU in children can be successfully managed with steroid instillation. In our series, 93.6% of children had complete resolution of symptoms. Georg Thieme Verlag KG Stuttgart · New York.

  16. Evaluation of stainless steel reinforcement construction project

    Science.gov (United States)

    2003-02-01

    Stainless steel reinforcement has greater corrosion resistance than that of the conventional reinforcement. In this project, bridge A6059, the first in Missouri utilizing stainless steel reinforcement in the deck, was constructed, along with bridge A...

  17. Static and dynamic mechanics of the murine lung after intratracheal bleomycin

    Directory of Open Access Journals (Sweden)

    Papiris Spyridon

    2011-05-01

    Full Text Available Abstract Background Despite its widespread use in pulmonary fibrosis research, the bleomycin mouse model has not been thoroughly validated from a pulmonary functional standpoint using new technologies. Purpose of this study was to systematically assess the functional alterations induced in murine lungs by fibrogenic agent bleomycin and to compare the forced oscillation technique with quasi-static pressure-volume curves in mice following bleomycin exposure. Methods Single intratracheal injections of saline (50 μL or bleomycin (2 mg/Kg in 50 μL saline were administered to C57BL/6 (n = 40 and Balb/c (n = 32 mice. Injury/fibrosis score, tissue volume density (TVD, collagen content, airway resistance (RN, tissue damping (G and elastance coefficient (H, hysteresivity (η, and area of pressure-volume curve (PV-A were determined after 7 and 21 days (inflammation and fibrosis stage, respectively. Statistical hypothesis testing was performed using one-way ANOVA with LSD post hoc tests. Results Both C57BL/6 and Balb/c mice developed weight loss and lung inflammation after bleomycin. However, only C57BL/6 mice displayed cachexia and fibrosis, evidenced by increased fibrosis score, TVD, and collagen. At day 7, PV-A increased significantly and G and H non-significantly in bleomycin-exposed C57BL/6 mice compared to saline controls and further increase in all parameters was documented at day 21. G and H, but not PV-A, correlated well with the presence of fibrosis based on histology, TVD and collagen. In Balb/c mice, no change in collagen content, histology score, TVD, H and G was noted following bleomycin exposure, yet PV-A increased significantly compared to saline controls. Conclusions Lung dysfunction in the bleomycin model is more pronounced during the fibrosis stage rather than the inflammation stage. Forced oscillation mechanics are accurate indicators of experimental bleomycin-induced lung fibrosis. Quasi-static PV-curves may be more sensitive than

  18. Static and dynamic mechanics of the murine lung after intratracheal bleomycin

    Science.gov (United States)

    2011-01-01

    Background Despite its widespread use in pulmonary fibrosis research, the bleomycin mouse model has not been thoroughly validated from a pulmonary functional standpoint using new technologies. Purpose of this study was to systematically assess the functional alterations induced in murine lungs by fibrogenic agent bleomycin and to compare the forced oscillation technique with quasi-static pressure-volume curves in mice following bleomycin exposure. Methods Single intratracheal injections of saline (50 μL) or bleomycin (2 mg/Kg in 50 μL saline) were administered to C57BL/6 (n = 40) and Balb/c (n = 32) mice. Injury/fibrosis score, tissue volume density (TVD), collagen content, airway resistance (RN), tissue damping (G) and elastance coefficient (H), hysteresivity (η), and area of pressure-volume curve (PV-A) were determined after 7 and 21 days (inflammation and fibrosis stage, respectively). Statistical hypothesis testing was performed using one-way ANOVA with LSD post hoc tests. Results Both C57BL/6 and Balb/c mice developed weight loss and lung inflammation after bleomycin. However, only C57BL/6 mice displayed cachexia and fibrosis, evidenced by increased fibrosis score, TVD, and collagen. At day 7, PV-A increased significantly and G and H non-significantly in bleomycin-exposed C57BL/6 mice compared to saline controls and further increase in all parameters was documented at day 21. G and H, but not PV-A, correlated well with the presence of fibrosis based on histology, TVD and collagen. In Balb/c mice, no change in collagen content, histology score, TVD, H and G was noted following bleomycin exposure, yet PV-A increased significantly compared to saline controls. Conclusions Lung dysfunction in the bleomycin model is more pronounced during the fibrosis stage rather than the inflammation stage. Forced oscillation mechanics are accurate indicators of experimental bleomycin-induced lung fibrosis. Quasi-static PV-curves may be more sensitive than forced oscillations

  19. Plating on stainless steel alloys

    International Nuclear Information System (INIS)

    Dini, J.W.; Johnson, H.R.

    1981-01-01

    Quantitative adhesion data are presented for a variety of electroplated stainless steel type alloys. Results show that excellent adhesion can be obtained by using a Wood's nickel strike or a sulfamate nickel strike prior to final plating. Specimens plated after Wood's nickel striking failed in the deposit rather than at the interface between the substrate and the coating. Flyer plate quantitative tests showed that use of anodic treatment in sulfuric acid prior to Wood's nickel striking even further improved adhesion. In contrast activation of stainless steels by immersion or cathodic treatment in hydrochloric acid resulted in very reduced bond strengths with failure always occurring at the interface between the coating and substrate

  20. On the influence of the instillation time on the results of HAL (Hexvix) fluorescence detection of superficial bladder cancer

    Science.gov (United States)

    Jichlinski, Patrice; Aymon, Daniela; Wagnieres, Georges A.; Marti, Alexandre; Lange, Norbert; Guillou, Louis; Leisinger, Hans-Juerg; van den Bergh, Hubert

    2003-10-01

    Hexyl aminolevulinate (HAL) fluorescence cystoscopy is being investigated as a new diagnostic tool for the detection of flat urothelial malignancies in bladder cancers. However, the influence of the bladder instillation time on the performance of this detection modality has not been addressed up to now. We report our initial experience comparing different instillation schedules of HAL cystoscopy in the diagnosis of superficial bladder cancer. A total of 718 fluorescent positive (433) and fluorescence negative (285) biopsies have been taken in the bladder of 143 patients using the Storz D-light fluorescence imaging system (Karl Storz, Tuttlingen, Germany) which allows both white and blue light (380-450 nm) bladder wall inspection. Following hospitalisation, 50 ml of HAL (8mM) phosphate buffer solution was instilled into the bladder of patients during one hour (1 hour protocol involving 57 patients), or during two hours followed by a two hours resting time after removal of the solution (2+2 hours protocol involving 86 patients). Both instillation subgroups were homogeneous in terms of proportion of high risk disease, previous BCG treatment and/or recurrent disease. This study indicates that the instillation duration does not influence the results of HAL (Hexvix) fluorescence cystoscopy in our conditions. Compared to the standard use of ALA, HAL (Hexvix) fluorescence cystoscopy allows a significant reduction of the instillation time (to less than one hour) without prejudicing the efficacy of the method, what represents a real advantage in daily clinical practice.

  1. Weld bonding of stainless steel

    DEFF Research Database (Denmark)

    Santos, I. O.; Zhang, Wenqi; Goncalves, V.M.

    2004-01-01

    This paper presents a comprehensive theoretical and experimental investigation of the weld bonding process with the purpose of evaluating its relative performance in case of joining stainless steel parts, against alternative solutions based on structural adhesives or conventional spot-welding. Th...

  2. Nickel release from stainless steels.

    Science.gov (United States)

    Haudrechy, P; Mantout, B; Frappaz, A; Rousseau, D; Chabeau, G; Faure, M; Claudy, A

    1997-09-01

    In 1994, a study of nickel release and allergic contact dermatitis from nickel-plated metals and stainless steels was published in this journal. It was shown that low-sulfur stainless steel grades like AISI 304, 316L or 430 (S AISI 303-S approximately 0.3%) releases about 1.5 micrograms/cm2/week in this acid artificial sweat. Applied on patients sensitized to nickel, these metals elicit positive reactions in 96% and 14%, respectively, of the patients. The main conclusion was that low-sulfur stainless steels like AISI 304, 316L or 430, even when containing Ni, should not elicit nickel contact dermatitis, while metals having a mean corrosion resistance like a high-sulfur stainless steel (AISI 303) or nickel-plated steel should be avoided. The determining characteristic was in fact the corrosion resistance in chloride media, which, for stainless steels, is connected, among other factors, to the sulfur content. Thus, a question remained concerning the grades with an intermediate sulfur content, around 0.03%, which were not studied. They are the object of the study presented in this paper. 3 tests were performed: leaching experiments, dimethylglyoxime and HNO3 spot tests, and clinical patch tests; however, only stainless steels were tested: a low-sulfur AISI 304 and AISI 303 as references and 3 grades with a sulfur content around 0.03%: AISI 304L, AISI 304L added with Ca, AISI 304L+Cu. Leaching experiments showed that the 4 non-resulfurised grades released less than 0.5 microgram/cm2/week in acid sweat while the reulfurized AISI 303 released around or more than 0.5 microgram/cm2/week. This is explained by the poorer corrosion resistance of the resulfurized grade. Yet all these grades had the same reaction to the DMG test (negative result), which shows again its lack of sensitivity. In contrast, the HNO3 spot test distinguished AISI 303 from the non-resulfurized grades. Clinical patch tests again showed that some patients (4%) were intolerant to AISI 303, while none were

  3. Combined radiofrequency ablation and acetic acid-hypertonic saline solution instillation: an in vivo study of rabbit liver

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong-Min; Han, Joon-Koo; Kim, Se-Hyung; Choi, Byung-Ihn [Seoul National University, Seoul (Korea, Republic of); Kim, Young-Kon; Kim, Sang-Won [Chonbuk National University, Chonju (Korea, Republic of)

    2004-03-15

    We wanted to determine whether combined radiofrequency ablation (RFA) and acetic acid-hypertonic saline solution (AHS) instillation can increase the extent of thermally mediated coagulation in in vivo rabbit liver tissue. We also wished to determine the optimal concentration of the solution in order to maximize its effect on extent of the RFA-induced coagulation. Forty thermal ablation zones were produced in 40 rabbits by using a 17-gauge internally cooled electrode with a 1-cm active tip under ultrasound guidance. The rabbits were assigned to one of four groups: group A: RFA alone (n=10); group B: RFA with 50% AHS instillation (n=10); group C: RFA with 25% AHS instillation (n=10); group D: RFA with 15% AHS instillation (n=10). A range of acetic acid concentrations diluted in 36% NaCl to a total volume of 2 mL were instilled into the liver before RFA. The RF energy (30W) was applied for three minutes. After RFA, in each group, the maximum diameters to the thermal ablation zones in the gross specimens were compared. Technical success and the complication that arose were evaluated by CT and on the basis of autopsy findings. All procedures are technically successful. There were six procedure-related complications (6/40; 15%); two localized perihepatic hematomas and four chemical peritonitis. The incidence of chemical peritonitis was highest for group B with the 50% AHS solution instillation (30%). With instillation of 15% AHS solution, a marked decrease of tissue impedance (24.5 {+-} 15.6 {omega}) and an increase of current (250 mA) occurred as compared to RFA alone. With instillation of the solutions before RFA (group B, C and D). this produced a greater mean diameter of coagulation necrosis than the diameters for rabbits not instilled with the solution (group A) ({rho}<0.05). However, there was no significant difference between group B, C, and D. Combined AHS instillation and RFA can increase the dimension of coagulation necrosis in the liver with a single

  4. Olfactory toxicity in rats following manganese chloride nasal instillation: A pilot study.

    Science.gov (United States)

    Foster, Melanie L; Rao, Deepa B; Francher, Taylor; Traver, Samantha; Dorman, David C

    2018-01-01

    Following inhalation, manganese travels along the olfactory nerve from the olfactory epithelium (OE) to the olfactory bulb (OB). Occupational exposure to inhaled manganese is associated with changes in olfactory function. This pilot study evaluated two related hypotheses: (a) intranasal manganese administration increases OE and OB manganese concentrations; and (b) intranasal manganese exposure impairs performance of previously trained rats on a go-no-go olfactory discrimination (OD) task. Male Fischer 344 rats were trained to either lever press ("go") in response to a positive conditioned stimulus (CS+: vanillin) or to do nothing ("no go") when a negative conditioned stimulus (CS-: amyl acetate) was present. Following odor training, rats were randomly assigned to either a manganese (200mM MnCl 2 ) or 0.9% saline treatment group (n=4-5 rats/group). Administration of either saline or manganese was performed on isoflurane-anesthetized rats as 40μL bilateral intranasal instillations. Rats were retested 48h later using the vanillin/amyl acetate OD task, then euthanized, followed by collection of the OE and OB. Manganese concentrations in tissue samples were analyzed by ICP-MS. An additional cohort of rats (n=3-4/group) was instilled similarly with saline or manganese and nasal and OB pathology assessed 48h later. Manganese-exposed rats had increased manganese levels in both the OE and OB and decreased performance in the OD task when compared with control animals. Histopathological evaluation of the caudal nasal cavity showed moderate, acute to subacute suppurative inflammation of the olfactory epithelium and submucosa of the ethmoid turbinates and mild suppurative exudate in the nasal sinuses in animals given manganese. No histologic changes were evident in the OB. The nasal instillation and OD procedures developed in this study are useful methods to assess manganese - induced olfactory deficits. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Use of radioactively labelled bacteria in animal experiments. 4. Distribution of radioactivity in the mouse after intratracheal administration of labelled Pasteurella multocida germs

    Energy Technology Data Exchange (ETDEWEB)

    Flossmann, K.D.; Mueller, G.; Heilmann, P.; Finsterbusch, L.; Hubald, J. (Akademie der Landwirtschaftswissenschaften der DDR, Jena. Inst. fuer Bakterielle Tierseuchenforschung)

    1981-03-01

    Intratracheal administration of /sup 3/H-, /sup 14/C-, /sup 59/Fe- or /sup 125/I-labelled Pasteurella multocida germs to mice resulted in a more or less differentiated, nuclidedependent distribution of radioactivity in blood, spleen, liver, lung, kidney, and gastrointestinal tract, and was comparable to that following subcutaneous application. The elimination of the antigen from the lungs and other organs could be characterised by an e function, after having reached a certain level of distribution. Some of the antigen was persistent in the lung not less than 14 days. Extremely high activity concentration and persistence was recordable, following the use of /sup 59/Fe complete antigen. Phagocytosis of Pasteurella multocida germs through alveolar macrophages of the lung was secured by autoradiography. Most of the antigen seemed to be discharged from the lungs through the digestive tract. Antigen distribution recorded from immunized and non-immunized mice seemed to suggest that the fate of antigen applied was affected by the kind of immunization. No difference in antigen distribution between non-immunized and subcutaneously immunized animals were provable, following intratracheal antigen application, but is was clearly provable, following intratracheal immunization. Elimination of antigen from the lungs of intratracheally immunized animals was found to occur faster than it did from non-immunized animals.

  6. Pathogenesis of infection with 2009 pandemic H1N1 influenza virus in isogenic guinea pigs after intranasal or intratracheal inoculation.

    Science.gov (United States)

    Wiersma, Lidewij C M; Vogelzang-van Trierum, Stella E; van Amerongen, Geert; van Run, Peter; Nieuwkoop, Nella J; Ladwig, Mechtild; Banneke, Stefanie; Schaefer, Hubert; Kuiken, Thijs; Fouchier, Ron A M; Osterhaus, Albert D M E; Rimmelzwaan, Guus F

    2015-03-01

    To elucidate the pathogenesis and transmission of influenza virus, the ferret model is typically used. To investigate protective immune responses, the use of inbred mouse strains has proven invaluable. Here, we describe a study with isogenic guinea pigs, which would uniquely combine the advantages of the mouse and ferret models for influenza virus infection. Strain 2 isogenic guinea pigs were inoculated with H1N1pdm09 influenza virus A/Netherlands/602/09 by the intranasal or intratracheal route. Viral replication kinetics were assessed by determining virus titers in nasal swabs and respiratory tissues, which were also used to assess histopathologic changes and the number of infected cells. In all guinea pigs, virus titers peaked in nasal secretions at day 2 after inoculation. Intranasal inoculation resulted in higher virus excretion via the nose and higher virus titers in the nasal turbinates than intratracheal inoculation. After intranasal inoculation, infectious virus was recovered only from nasal epithelium; after intratracheal inoculation, it was recovered also from trachea, lung, and cerebrum. Histopathologic changes corresponded with virus antigen distribution, being largely limited to nasal epithelium for intranasally infected guinea pigs and more widespread in the respiratory tract for intratracheally infected guinea pigs. In summary, isogenic guinea pigs show promise as a model to investigate the role of humoral and cell-mediated immunities to influenza and their effect on virus transmission. Copyright © 2015 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  7. Anelasticity in austenitic stainless steel

    International Nuclear Information System (INIS)

    Time-dependent anelastic deformation mechanisms arise in austenitic stainless steel when load is removed during a high-temperature creep test. This phenomenon is investigated by conducting creep tests, with intermittent load removal, on AISI Type 316H austenitic stainless steel at 550 and 650 °C, supported by in situ measurement of creep-induced intergranular residual strains by neutron diffraction. All the cyclic tests exhibit anelastic behaviour on unloading and develop substantially lower load-on creep strain rates, reduced ductility and longer rupture times than baseline steady-load creep tests at similar conditions. The mechanisms underlying the observed anelastic behaviour and changes in macroscopic creep properties are discussed with reference to the development of intergranular strains and dislocation behaviour.

  8. Analyzing the effects of instillation volume on intravesical delivery using biphasic solute transport in a deformable geometry.

    Science.gov (United States)

    Smith, Sean G; Griffith, Boyce E; Zaharoff, David A

    2018-04-05

    Ailments of the bladder are often treated via intravesical delivery-direct application of therapeutic into the bladder through a catheter. This technique is employed hundreds of thousands of times every year, but protocol development has largely been limited to empirical determination. Furthermore, the numerical analyses of intravesical delivery performed to date have been restricted to static geometries and have not accounted for bladder deformation. This study uses a finite element analysis approach with biphasic solute transport to investigate several parameters pertinent to intravesical delivery including solute concentration, solute transport properties and instillation volume. The volume of instillation was found to have a substantial impact on the exposure of solute to the deeper muscle layers of the bladder, which are typically more difficult to reach. Indeed, increasing the instillation volume from 50-100 ml raised the muscle solute exposure as a percentage of overall bladder exposure from 60-70% with higher levels achieved for larger instillation volumes. Similar increases were not seen for changes in solute concentration or solute transport properties. These results indicate the role that instillation volume may play in targeting particular layers of the bladder during an intravesical delivery.

  9. [Control of the rabbit's IOP after topic instillation of antiglaucomatic latanoprost and amino acid arginine with lysine mixture].

    Science.gov (United States)

    Veselovský, J; Oláh, Z; Veselá, A; Gressnerová, S

    2007-04-01

    To evaluate the effect of locally instilled 10% L-arginine.HCI and 10% L-lysine.2HC1.2H20 in 0.005% Latanoprost (Xalatane) mixture on the physiological IOP in rabbits. After instillation of the arginine and lysine in 0.005% latanoprost mixture into the left conjunctival sac of 5 female rabbits of the New Zealand White species the, IOP was measured at the time of instillation, and 5, 15, 30, 60, 120, 180, 240 min. and 24 hours after the instillation. The right eye was used as the control. The mixture of arginine with lysine in 0.005% latanoprost decreased significantly the IOP value. The decrease had two peaks. The major decrease of the IOP was observed after 30 min. (3.1 mmHg) and after 24 h (5.0 mmHg) after instillation of this mixture. Between 120 min. and to 240 min., the mild decrease of the mean value of the IOP was found at the control eye as well. The mixture of arginine with lysine in 10 % concentration in 0.005 % latanoprost (Xalatane) decreased significantly the physiological IOP values in rabbits during the whole experiment. The decrease was significant in comparison both to the IOP of the control eye and to the effect of the amino acids arginine and lysine alone.

  10. Thermophysical properties of stainless steels

    International Nuclear Information System (INIS)

    Kim, C.S.

    1975-09-01

    Recommended values of the thermodynamic and transport properties of stainless steels Type 304L and Type 316L are given for temperatures from 300 to 3000 0 K. The properties in the solid region were obtained by extrapolating available experimental data to the melting range, while appropriate correlations were used to estimate the properties in the liquid region. The properties evaluated include the enthalpy, entropy, specific heat, vapor pressure, density, thermal expansion coefficient, thermal conductivity, thermal diffusivity, and viscosity. (9 fig, 11 tables)

  11. Nano-composite stainless steel

    Science.gov (United States)

    Dehoff, Ryan R.; Blue, Craig A.; Peter, William H.; Chen, Wei; Aprigliano, Louis F.

    2015-07-14

    A composite stainless steel composition is composed essentially of, in terms of wt. % ranges: 25 to 28 Cr; 11 to 13 Ni; 7 to 8 W; 3.5 to 4 Mo; 3 to 3.5 B; 2 to 2.5 Mn; 1 to 1.5 Si; 0.3 to 1.7 C; up to 2 O; balance Fe. The composition has an austenitic matrix phase and a particulate, crystalline dispersed phase.

  12. Intratracheal Administration of Mesenchymal Stem Cells Modulates Tachykinin System, Suppresses Airway Remodeling and Reduces Airway Hyperresponsiveness in an Animal Model.

    Directory of Open Access Journals (Sweden)

    Konrad Urbanek

    Full Text Available The need for new options for chronic lung diseases promotes the research on stem cells for lung repair. Bone marrow-derived mesenchymal stem cells (MSCs can modulate lung inflammation, but the data on cellular processes involved in early airway remodeling and the potential involvement of neuropeptides are scarce.To elucidate the mechanisms by which local administration of MSCs interferes with pathophysiological features of airway hyperresponsiveness in an animal model.GFP-tagged mouse MSCs were intratracheally delivered in the ovalbumin mouse model with subsequent functional tests, the analysis of cytokine levels, neuropeptide expression and histological evaluation of MSCs fate and airway pathology. Additionally, MSCs were exposed to pro-inflammatory factors in vitro.Functional improvement was observed after MSC administration. Although MSCs did not adopt lung cell phenotypes, cell therapy positively affected airway remodeling reducing the hyperplastic phase of the gain in bronchial smooth muscle mass, decreasing the proliferation of epithelium in which mucus metaplasia was also lowered. Decrease of interleukin-4, interleukin-5, interleukin-13 and increase of interleukin-10 in bronchoalveolar lavage was also observed. Exposed to pro-inflammatory cytokines, MSCs upregulated indoleamine 2,3-dioxygenase. Moreover, asthma-related in vivo upregulation of pro-inflammatory neurokinin 1 and neurokinin 2 receptors was counteracted by MSCs that also determined a partial restoration of VIP, a neuropeptide with anti-inflammatory properties.Intratracheally administered MSCs positively modulate airway remodeling, reduce inflammation and improve function, demonstrating their ability to promote tissue homeostasis in the course of experimental allergic asthma. Because of a limited tissue retention, the functional impact of MSCs may be attributed to their immunomodulatory response combined with the interference of neuropeptide system activation and tissue

  13. Evaluation of the conservative treatment of Trigger finger by local instillation of corticosteroids

    Directory of Open Access Journals (Sweden)

    Muris Pecar

    2011-12-01

    Full Text Available Introduction: Trigger Finger (tenosynovitis stenosans is a specific, named disease from a group of repetitive strain injury (RSI diseases, caused by inflammation which results in difficulties during muscle contraction and weakened and painful tendon movement. It is common in the outpatient physical medicine and rehabilitation practice. The aim of our study was to evaluate the success of conservative treatment of Trigger Finger by local instillation of corticosteroids.Methods: The study was designed as an observational and open analysis of the results of conservative treatment of 45 patients. We used precise instillation of steroid anti-inflammatory antirheumatic drugs in the area of patho-anatomic, microtraumatic injuries of tendon and its sheath. Patients were evaluated before and after the treatment with 0 to 5 evaluation score scale. The data were analyzed using X2 test.Results: Most of the patients had evaluation score of 2, 3 and 4, before the treatment. After the treatment 10 (29% patients had achieved score 4 and 35 (71% patients had achieved score 5. All of the patients with score 5 had excellent working ability with full working capacity. Other patients had well-preserved working ability, which improved to excellent in maximum of 7 days.Conclusions: Conservative treatment of Trigger finger shows good therapeutic effects and taking into account the benefits, convenience and generally lower cost of conservative treatment for the patient, should be considered as an effective alternative to surgical treatment.

  14. Endometritis therapy in sows by intra uterine instillation of yeast cell wall solution

    Directory of Open Access Journals (Sweden)

    Lazarević M.

    2012-01-01

    Full Text Available On the basis of our investigations it was possible to conclude that intrauterine treatment of sows with puerperal uterine infections with sterile YCW (Yeast Cell Wall resulted in significant clinical improvement. The percent of recidivism was the lowest (10% in groups of sows treated with 10 and 20 g of YCW. The degree of bacterial CFU (Colony Forming Units reduction in samples of sows uterine flushings following instillation of YCW (5, 10 and 20 g was wery high and ranged from 1361 to 1444 times, while in sows treated with Lotagen 2% solution (100 mL this parametar was only 32. At the moment of weaning, piglets from sows treated with 10 and 20 g of YCW were heavier when compared to the control and Lotagen group and their DBWG (Daily Body Weight Gain was higher when compared to the Lotagen and control group. Treatment of sows by IU instillation of YCW did not influence the number of piglets in the next breeding cycle.

  15. Metabolism of nasally instilled benzo(a)pyrene and dihydrosafrole in dogs and monkeys

    International Nuclear Information System (INIS)

    Petridou-Fischer, J.; Whaley, S.; Dahl, A.

    1987-01-01

    Cytochrome P-450 monooxygenases are found in the nasal cavities of a variety of species and could play an important role in the metabolism of inhaled airborne xenobiotics. The object of this study was to examine the metabolism of 14 C-benzo(a)pyrene (BaP) and 3 H-dihydrosafrole (DHS) deposited at the ethmoid and maxillary turbinate regions in Beagle dogs and Cynomolgus monkeys. While the animals were anesthetized, either compound was instilled at 10 minute intervals for 2 hours through catheters positioned at each region. Cotton swab samples of mucus from the nasopharynx were collected at 30 minute intervals during instillation. Metabolites in mucus were identified using high pressure liquid chromatography. Results showed that both regions in both species were capable of metabolizing BaP and DHS. BaP metabolites identified in the mucus were dihydrodiols, quinones, phenols, and tetrols. DHS metabolites were 2-methoxy-4-propyl-phenol, 2-methoxy-4-(2-propenyl)benzene, and 3,4-methylenedioxy-1-(1-hydroxypropyl)benzene. Radioactivity was found in urine and feces of animals treated with either compound, and was detected in the blood of animals treated with DHS. No differences were noted for the nasal metabolism between the two species. This study indicated that not only the nasal tissues, but also the alimentary tract, may be exposed to metabolites of inhaled xenobiotics carried by the mucus

  16. Health-Care Associated Mycobacterium bovis-BCG Infection in Cancer Patients without prior BCG Instillation.

    Science.gov (United States)

    Meije, Y; Martínez-Montauti, J; Caylà, J A; Loureiro, J; Ortega, L; Clemente, M; Sanz, X; Ricart, M; Santomà, M J; Coll, P; Sierra, M; Calsina, M; Vaqué, M; Ruiz-Camps, I; López-Sánchez, C; Montes, M; Ayestarán, A; Carratalà, J; Orcau, A

    2017-05-29

    Bacille Calmette-Guérin (BCG), an attenuated strain of Mycobacterium bovis, is widely used as adjunctive therapy for superficial bladder cancer. Intravesical administration of BCG has been associated with systemic infection. Disseminated infection due to M. bovis is otherwise uncommon. After identification of three patients with health-care associated BCG infection (HCBCGI) who had never received intravesical BCG administration, an epidemiologic study was performed. All patients with HCBCGI in the Barcelona tuberculosis (TB) program were reviewed from January 1, 2005 to December 31, 2015 searching for infections caused by M. bovis-BCG. Patients with HCBCGI who had not received intravesical BCG instillation were selected and the source of infection was investigated. Nine oncology patients with infection caused by M. bovis-BCG were studied. All had permanent central venous catheters. Catheter maintenance was performed at four different outpatient clinics in the same room in which other patients underwent BCG instillations for bladder cancer without required biological precautions. All patients developed pulmonary TB, either alone or with extrapulmonary disease. Catheter-related infection was considered the mechanism of acquisition based on the epidemiologic association and positive catheter cultures for BCG in patients in whom mycobacterial cultures were performed. Physicians should be alerted to the possibility of TB due to nosocomially acquired, catheter-related infections with M. bovis-BCG in patients with indwelling catheters. This problem may be more common than expected in centers providing BCG therapy for bladder cancer without adequate precautions.

  17. Hybrid Stainless Steel Girder for Bridge Construction

    OpenAIRE

    Tetsuya Yabuki; Yasunori Arizumi; Tetsuhiro Shimozato; Samy Guezouli; Hiroaki Matsusita; Masayuki Tai

    2017-01-01

    The main object of this paper is to present the research results of the development of a hybrid stainless steel girder system for bridge construction undertaken at University of Ryukyu. In order to prevent the corrosion damage and reduce the fabrication costs, a hybrid stainless steel girder in bridge construction is developed, the stainless steel girder of which is stiffened and braced by structural carbon steel materials. It is verified analytically and experimentally that the ultimate stre...

  18. Palpebral position interdependence in blepharoptosis: comparison of the effect of instillation of 10% phenylephrine drop and digital lifting

    Directory of Open Access Journals (Sweden)

    Ivana Cardoso Pereira

    2014-12-01

    Full Text Available Purpose: To quantify and compare the effects of instillation with 10% phenylephrine and digital lifting on the contralateral upper eyelid of patients with involutional bilateral blepharoptosis. Methods: The present prospective clinical study involved patients with involutional bilateral blepharoptosis who underwent two tests: 1 digital lifting of the more ptotic eyelid and observation of the effect on the contralateral eyelid and 2 instillation of two drops of 10% phenylephrine in the more ptotic eye and observation of the effect on the contralateral eyelid. Patients were filmed before and 5, 10, and 15 min after instillation, and the resulting images were analyzed to obtain eyelid measurements. The results were tested using a linear mixed-effects model. Results: A total of 27 patients, ranging from 52 to 82 years of age (mean age 68.51 ± 8.21 years, 24 (88.88% of whom were women, were included in the present study. In eyes that received instillation, the marginal distance reflex-1 (MDR1 values increased from baseline (1.21 ± 0.60 mm until 10 min after instillation, then remained statistically unchanged until 15 min after instillation (2.42 ± 0.90 mm. Significant differences were observed in the contralateral eye of the group that underwent digital lifting (1.51 ± 0.53 mm - 1.63 ± 0.56 mm and in the contralateral eye of the group that underwent 10% phenylephrine instillation (1.38 ± 0.54 mm - 1.63 ± 0.56 mm; p=0.02 and p<0.01, respectively. Conclusion: In all eyes, 10% phenylephrine elevated the upper eyelid, with improved eyelid height at 10 min after instillation. Significant differences were observed in the height of the contralateral eyelid when compared before and after each intervention in each group; however, this difference was very small and nearly undetectable by conventional clinical evaluation in the digital lifting group. However, the 10% phenylephrine eye-drop test resulted in substantial changes in MDR1 values in the

  19. Alterations in cardiomyocyte function after pulmonary treatment with stainless steel welding fume in rats.

    Science.gov (United States)

    Popstojanov, Risto; Antonini, James M; Salmen, Rebecca; Ye, Morgan; Zheng, Wen; Castranova, Vincent; Fekedulegn, Desta B; Kan, Hong

    2014-01-01

    Welding fume is composed of a complex of different metal particulates. Pulmonary exposure to different welding fumes may exert a negative impact on cardiac function, although the underlying mechanisms remain unclear. To explore the effect of welding fumes on cardiac function, Sprague-Dawley rats were exposed by intratracheal instillation to 2 mg/rat of manual metal arc hard surfacing welding fume (MMA-HS) once per week for 7 wk. Control rats received saline. Cardiomyocytes were isolated enzymatically at d 1 and 7 postexposure. Intracellular calcium ([Ca(2+)]i) transients (fluorescence ratio) were measured on the stage of an inverted phase-contrast microscope using a myocyte calcium imaging/cell length system. Phosphorylation levels of cardiac troponin I (cTnI) were determined by Western blot. The levels of nonspecific inflammatory marker C-reactive protein (CRP) and proinflammatory cytokine interleukin-6 (IL-6) in serum were measured by enzyme-linked immunosorbent assay (ELISA). Contraction of isolated cardiomyocytes was significantly reduced at d 1 and d 7 postexposure. Intracellular calcium levels were decreased in response to extracellular calcium stimulation at d 7 postexposure. Changes of intracellular calcium levels after isoprenaline hydrochloride (ISO) stimulation were not markedly different between groups at either time point. Phosphorylation levels of cTnI in the left ventricle were significantly lower at d 1 postexposure. The serum levels of CRP were not markedly different between groups at either time point. Serum levels of IL-6 were not detectable in both groups. Cardiomyocyte alterations observed after welding fume treatment were mainly due to alterations in intracellular calcium handling and phosphorylation levels of cTnI.

  20. In what type of interstitial cystitis/bladder pain syndrome is DMSO intravesical instillation therapy effective?

    Science.gov (United States)

    2015-01-01

    Background Dimethylsulfoxide (DMSO) is the most-used agent for intravesical instillation. We conducted this retrospective clinical study to determine in what type of the interstitial cystitis (IC)/bladder pain syndrome (BPS) DMSO was effective. Methods We combined DMSO with hydrodistension in 2003 and from 2004 we performed hydrodistension alone. Hydrodistension had been performed in 7 cases of IC/BPS with Hunner’s lesions (H group) and 7 cases of IC/BPS without Hunner’s lesions (non-H group), and they served as the control group (C group; n=14). There was also a DMSO group (D group; n=14) that consisted of an H group of 7 cases and an non-H group of 7 cases in which the hydrodistension had been immediately followed by intravesical instillation of 50% DMSO 50 mL. Before, and 2, 6, 12, 18, and 24 months (M) after the intervention, the patients were asked to complete a 4-day frequency-volume chart (FVC) and the O’Leary-Sant IC symptom index (ICSI) questionnaire and IC problem index (ICPI) questionnaire, and to rate their pain on a visual analogue scale (VAS). Results All parameters were improved after hydrodistension in both the C group and the D group. However, comparison of the C group and D group according to whether Hunner lesions were present showed that there were no significant differences in any of the postoperative parameters between the non-H groups in the C group and D group, but in the H groups, average and maximum voided volume were significantly higher and the ICSI, ICPI, and VAS scores were lower in the D group. Moreover, the significant differences increased with the duration of the postoperative period. Conclusions DMSO intravesical instillation therapy was useful in both maintaining and improving the effectiveness of hydrodistension in IC/BPS with Hunner lesions. However, DMSO did not have any particular efficacy in the treatment of IC/BPS in the absence of Hunner lesions. PMID:26816859

  1. Negative Pressure Wound Therapy With Instillation: Review of Evidence and Recommendations.

    Science.gov (United States)

    Kim, Paul J; Attinger, Christopher E; Olawoye, Olayinka; Crist, Brett D; Gabriel, Allen; Galiano, Robert D; Gupta, Subhas; Lantis Ii, John C; Lavery, Lawrence; Lipsky, Benjamin A; Teot, Luc

    2015-12-01

    Negative pressure wound therapy with instillation (NPWTi) and dwell time is an adjunctive treatment modality for selected complex wounds. Because of the greater amount of research now available, a multidisciplinary expert panel comprising the fields of podiatry, plastic and general surgery, burn treatment, infectious diseases, and orthopedics was convened on July 11, 2015, to produce a summary of the data and recommendations on the use of NPWTi. The panel members each reviewed available published literature on NPWTi in the PubMed, Cochrane, and Google Scholar databases from 1 January 2012 up until 20 July 2015 using the string search term negative pressure wound therapy instillation provided by the panel moderator; there were no restrictions on the language or type of publication. Panel members discussed their experiences and worked to reach consensus on several predefined topics. NPWTi was found to be most appropriate for properly selected complex hosts or wounds such as patients with multiple comorbidities, patients with an American Society of Anesthesiology Classification ≥ 2, severe traumatic wounds, diabetic foot infections, and wounds complicated by invasive infection or extensive biofilm. NPWTi should not be used routinely to treat simple wounds or hosts without comorbidities.There is evidence that when NPWTi is added to standard of care in properly selected cases it provides better overall clinical outcomes than standard of care alone, even when including NPWT. Based on published evidence and panel member experience, the Panel recommends a dwell time - fluid briefly instilled into the wound and allowed to diffuse for a user-specified time - of 10-20 minutes followed by 2-4 hours of negative pressure at -125 mmHg, although larger wounds may need times of up to 6 hours. Normal saline (0.9%) is the preferred solution for NPWTi, except in special situations. NPWTi with dwell time is an adjunct to other standard principles of appropriate wound assessment and

  2. Assessment of ocular surface toxicity after topical instillation of nitric oxide donors

    Directory of Open Access Journals (Sweden)

    Angelino Julio Cariello

    2013-02-01

    Full Text Available PURPOSE: To evaluate the ocular surface toxicity of two nitric oxide donors in ex vivo and in vivo animal models: S-nitrosoglutathione (GSNO and S-nitroso-N-acetylcysteine (SNAC in a hydroxypropyl methylcellulose (HPMC matrix at final concentrations 1.0 and 10.0 mM. METHODS: Ex vivo GSNO and SNAC toxicities were clinically and histologically analyzed using freshly excised pig eyeballs. In vivo experiments were performed with 20 albino rabbits which were randomized into 4 groups (5 animals each: Groups 1 and 2 received instillations of 150 µL of aqueous HPMC solution containing GSNO 1.0 and 10.0 mM, respectively, in one of the eyes; Groups 3 and 4 received instillations of 150 µL of aqueous HPMC solution-containing SNAC 1.0 and 10.0 mM, respectively, in one of the eyes. The contralateral eyes in each group received aqueous HPMC as a control. All animals underwent clinical evaluation on a slit lamp and the eyes were scored according to a modified Draize eye test and were histologically analyzed. RESULTS: Pig eyeballs showed no signs of perforation, erosion, corneal opacity or other gross damage. These findings were confirmed by histological analysis. There was no difference between control and treated rabbit eyes according to the Draize eye test score in all groups (p>0.05. All formulations showed a mean score under 1 and were classified as "non-irritating". There was no evidence of tissue toxicity in the histological analysis in all animals. CONCLUSION: Aqueous HPMC solutions containing GSNO and SNAC at concentrations up to 10.0 mM do not induce ocular irritation.

  3. Assessment of ocular surface toxicity after topical instillation of nitric oxide donors.

    Science.gov (United States)

    Cariello, Angelino Julio; Souza, Gabriela Freitas Pereira de; Lowen, Márcia Serva; Oliveira, Marcelo Ganzarolli de; Höfling-Lima, Ana Luisa

    2013-01-01

    To evaluate the ocular surface toxicity of two nitric oxide donors in ex vivo and in vivo animal models: S-nitrosoglutathione (GSNO) and S-nitroso-N-acetylcysteine (SNAC) in a hydroxypropyl methylcellulose (HPMC) matrix at final concentrations 1.0 and 10.0 mM. Ex vivo GSNO and SNAC toxicities were clinically and histologically analyzed using freshly excised pig eyeballs. In vivo experiments were performed with 20 albino rabbits which were randomized into 4 groups (5 animals each): Groups 1 and 2 received instillations of 150 µL of aqueous HPMC solution containing GSNO 1.0 and 10.0 mM, respectively, in one of the eyes; Groups 3 and 4 received instillations of 150 µL of aqueous HPMC solution-containing SNAC 1.0 and 10.0 mM, respectively, in one of the eyes. The contralateral eyes in each group received aqueous HPMC as a control. All animals underwent clinical evaluation on a slit lamp and the eyes were scored according to a modified Draize eye test and were histologically analyzed. Pig eyeballs showed no signs of perforation, erosion, corneal opacity or other gross damage. These findings were confirmed by histological analysis. There was no difference between control and treated rabbit eyes according to the Draize eye test score in all groups (p>0.05). All formulations showed a mean score under 1 and were classified as "non-irritating". There was no evidence of tissue toxicity in the histological analysis in all animals. Aqueous HPMC solutions containing GSNO and SNAC at concentrations up to 10.0 mM do not induce ocular irritation.

  4. Solidification cracking in austenitic stainless steel welds

    Indian Academy of Sciences (India)

    M. Senthilkumar (Newgen Imaging) 1461 1996 Oct 15 13:05:22

    V Shankar et al. Although much research experience exists on the nature of hot cracking in stainless steels ... that crack-resistant weld deposits could be produced if the composition is adjusted to result in 5–35% fer- .... A large volume of literature is devoted to the prediction and measurement of δ-ferrite in stainless steel ...

  5. The value of perioperative mitomycin C instillation in improving subsequent bacillus calmette-guerin instillation efficacy in intermediate and high-risk patients with non-muscle invasıve bladder cancer: a prospective randomized study

    Directory of Open Access Journals (Sweden)

    Ömer Gülpinar

    2012-08-01

    Full Text Available PURPOSE: We evaluated the efficacy of perioperative mitomycin C (MMC instillation to improve subsequent bacillus Calmette-Guérin (BCG instillation efficacy in intermediate and high risk patients with non-muscle invasive bladder cancer (NMIBC. MATERIALS AND METHODS: From November 2004 to May 2006, 51 patients with intermediate or high risk NMIBC were enrolled in this prospective randomized trial. In group A, patients were treated with perioperative MMC (40 mg MMC in 40 mL saline was administered within 6 hours of surgery followed by delayed (at least 15 days from surgery BCG instillations (once a week for 6 weeks, 5 x 108 colony-forming units in 50 mL saline. Patients in group B were treated with delayed BCG instillations alone. The primary end points were recurrence-free interval and recurrence rate. RESULTS: There were 25 and 26 patients in groups A and B, respectively. Median follow-up was 41.3 months (range 8 to 64 in group A and 40.9 months (range 6 to 68 in group B. Recurrence rate was 36% (9 of 25 and 19.3% (5 of 26 in group A and B, respectively (p = 0.052. Median time to the first recurrence was 8 months in group A and 7 months in group B (p = 0.12. CONCLUSIONS: The present study showed no statistically significant difference in terms of recurrence rate and median time to first recurrence between intermediate or high-risk patients with NMIBC who were treated with early single dose instillation of MMC plus delayed BCG and those who were treated with only BCG.

  6. Analgesic Efficacy of Intrarectal Instillation of Lidocaine Gel prior to Transrectal Ultrasound Guided Prostate Biopsy: A Prospective Randomized Trial

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Tae Jin; Kim, Seung Hyup; Cho, Jeong Yeon [Seoul National University Hospital, Seoul (Korea, Republic of); Lee, Hak Jong; Lee, Sang Eun; Byun, Seok Soo [Seoul National University Bundang Hospital, Seongnam (Korea, Republic of); Seong, Chang Kyu [Seoul National University Borame Hospital, Seoul (Korea, Republic of)

    2006-06-15

    To assess the analgesic efficacy of intrarectal lidocaine gel instillation prior to periprostatic nerve block during transrectal, ultrasound-guided prostate biopsies. Between March 2004 and October 2004, 203 consecutive patients for prostate biopsies were randomized into two groups. In 90 patients of group A, 10ml of 2% lidocaine gel was instilled intrarectally 10 minutes prior to periprostatic neurovascular bundle block, while 113 patients of group B received only periprostatic neurovascular bundle block without lidocaine gel instillation. Pain was assessed with the visual analogue pain scale, during periprostatic neurovascular bundle block (VAS 1), during the biopsy procedures (VAS 2) and 20 minutes after the procedure (VAS 3). The difference in VAS scores between patients in the two groups was evaluated with the unpaired t-test, with p < 0.05 considered significant. Patients in group A experienced statistically less pain during transrectal ultrasound guided prostate biopsy (VAS 2, 2.994 versus 3.903, p < 0.01). However, no significant difference in VAS values could be demonstrated during periprostatic neurovascular bundle block (VAS 1, 4.761 versus 5.133, p > 0.05) or at after 20 minutes after the procedure (VAS 3, 0.9778 versus 1.257, p > 0.05). Intrarectal instillation of lidocaine gel leads to significant additional analgesic efficacy during the biopsy procedure. It is a simple, safe and rapid technique that should be considered in all patients undergoing TRUS guided prostate biopsy

  7. Disseminated Mycobacterium bovis Infection Complicating Intravesical BCG Instillation for the Treatment of Superficial Transitional Cell Carcinoma of the Bladder.

    Science.gov (United States)

    Elzein, Fatehi; Albogami, Nada; Saad, Mustafa; El Tayeb, Nazik; Alghamdi, Abdullah; Elyamany, Ghaleb

    2016-01-01

    Intravesical instillation of Bacillus Calmette-Guérin (BCG) remains a first-line treatment for superficial transitional cell carcinoma of the bladder. Although its use is relatively safe, severe complications such as granulomatous hepatitis, osteomyelitis, pneumonitis, and sepsis occur in few patients. Complications of intravesical instillation of BCG can be local or systemic, with early or late presentation. Here, we report an 88-year-old man who developed fever, rigors, and episodes of syncope following fourth intravesical BCG instillation for the treatment of superficial transitional cell carcinoma of the bladder. Pancytopenia, disseminated intravascular coagulation, ground glass appearance on computerized tomography of the chest scan in addition to multiple bone marrow granulomas, suggested the diagnosis of disseminated BCG infection. All these features recovered on antituberculosis treatment. Our case study highlights the importance of early recognition and prompt treatment of patients with disseminated BCG infection following intravesical instillation. Although isolation of mycobacterium is desirable to make the diagnosis, it is not unusual to have negative smears and cultures and this should not be used to dismiss the possibility of BCG infection.

  8. The comparison of frictional resistance in titanium, self-ligating stainless steel, and stainless steel brackets using stainless steel and TMA archwires: An in vitro study

    Directory of Open Access Journals (Sweden)

    Syed Altaf Khalid

    2012-01-01

    Full Text Available Aim: The aim of the study was to compare the frictional resistance of titanium, self-ligating stainless steel, and conventional stainless steel brackets, using stainless steel and titanium molybdenum alloy (TMA archwires. Materials and Methods: We compared the frictional resistance in 0.018 slot and 0.022 slot of the three brackets - titanium, self-ligating stainless steel, and conventional stainless steel - using stainless steel archwires and TMA archwires. An in vitro study of simulated canine retraction was undertaken to evaluate the difference in frictional resistance between titanium, self-ligating stainless steel, and stainless steel brackets, using stainless steel and TMA archwires. Results and Conclusion: We compared the frictional resistance of titanium, self-ligating stainless steel, and conventional stainless steel brackets, using stainless steel and TMA archwires, with the help of Instron Universal Testing Machine. One-way analysis of variance (ANOVA, Student′s "t" test, and post hoc multiple range test at level of <0.05 showed statistically significant difference in the mean values of all groups. Results demonstrated that the titanium, self-ligating stainless steel, and stainless steel brackets of 0.018-inch and 0.022-inch slot had no significant variations in frictional résistance. The self-ligating bracket with TMA archwires showed relatively less frictional resistance compared with the other groups. The titanium bracket with TMA archwires showed relatively less frictional resistance compared with the stainless steel brackets.

  9. Pretreatment Features to Influence Effectiveness of Intravesical Hyaluronic Acid Instillation in Refractory Interstitial Cystitis/Painful Bladder Syndrome

    Science.gov (United States)

    Kim, Aram; Lim, Bumjin; Song, Miho

    2014-01-01

    Purpose To determine the efficacy of intravesical hyaluronic acid (HA) instillation in treating patients with refractory interstitial cystitis/painful bladder syndrome (IC/PBS) and to identify any related factors that influence its therapeutic effect. Methods Thirty-three female IC/PBS patients who demonstrated poor or unsatisfactory responses to previous treatments between December 2010 and October 2012 were enrolled. Despite previous treatments, the enrolled patients had visual analogue scale (VAS) pain scores ≥4 and total scores (symptom and bother scores) ≥13 on the pelvic pain and urgency/frequency (PUF) questionnaire and ≥12 on the O'Leary-Sant interstitial cystitis symptoms index (ICSI)/problems index (ICPI). All patients received once weekly intravesical instillations of 40-mg HA diluted in 50-mL saline for 4 weeks. The efficacy of the HA instillation was evaluated by comparing the mean changes in the scores of the VAS and questionnaires from baseline to 4 weeks after treatment. Improvement was defined as a ≥2 decrease in the VAS. Moreover, we investigated the effects of the presence of Hunner's ulcer and previous treatment modalities on the therapeutic outcome of HA instillation. Results The mean age was 57.0±1.8 years (range, 28-75 years). The VAS score significantly decreased from baseline to 4 weeks after treatment (-2.5, P<0.001). The mean changes in the PUF, ICSI, and ICPI from baseline to 4 weeks after the treatment were -3.8 (P<0.001), -2.3 (P<0.001), and -2.7 (P<0.001), respectively. Twenty patients (61%) showed improvements. Previous treatment modalities did not affect the efficacy of HA instillation and the presence of Hunner's ulcer was unrelated to outcomes. No complications were observed. Conclusions These results show that intravesical HA instillation is an effective and safe treatment for patients with refractory IC/PBS. Previous treatment modalities and presence of Hunner's ulcer do not affect the efficacy of HA instillation. PMID

  10. Mini-open vacuum-assisted closure therapy with instillation for debilitated and septic patients with pleural empyema.

    Science.gov (United States)

    Sziklavari, Zsolt; Ried, Michael; Neu, Reiner; Schemm, Rudolf; Grosser, Christian; Szöke, Tamas; Hofmann, Hans-Stefan

    2015-08-01

    This prospective study is an evaluation of the mini-open vacuum-assisted closure with instillation (Mini-VAC-Instill) therapy for the treatment of complicated pleural empyema. We investigated septic patients in poor general physical condition (Karnofsky index ≤50%) with multimorbidity and/or immunosuppression who were treated by minimally invasive intrathoracic VAC-Instill therapy without the insertion of an open-window thoracostomy (OWT) between December 2012 and November 2014. All patients underwent mini-thoracotomy with position of a tissue retractor, surgical debridement and local decortication. Surgery was followed by intrathoracic vacuum therapy including periodic instillation using antiseptics. The VAC dressings were changed under general anaesthesia and the chest wall was closed during the same hospital stay. All patients received systemic antibiotic therapy. Fifteen patients (13 males, median age: 71 years) underwent intrathoracic Mini-VAC-Instill dressings for the management of pleural empyema without bronchopleural fistula. The median length of vacuum therapy was 9 days (5-25 days) and the median number of VAC changes per patient was 1 (1-5). In-hospital mortality was 6.7% (n = 1) and was not related to Mini-VAC-Instill therapy or intrathoracic infection. Control of intrathoracic infection and closure of the chest cavity was achieved in 85.7% of surviving patients (12 of 14). After the follow-up at an average of 13.2 months (range, 3-25 months), we observed recurrence once, 21 days after discharge. Two patients died in the late postoperative period (Day 43 and Day 100 after discharge) of fulminant urosepsis and carcinoma-related multiorgan failure, respectively. Analysis of the follow-up interviews in the outpatient clinic showed a good quality of life and a subjectively good long-term aesthetic result. Mini-VAC-Instill therapy is an upgrade of Mini-VAC, which guarantees the advantage of an open treatment, including flushing but without OWT. This

  11. Hydrogen Gas Inhalation Attenuates Seawater Instillation-Induced Acute Lung Injury via the Nrf2 Pathway in Rabbits.

    Science.gov (United States)

    Diao, Mengyuan; Zhang, Sheng; Wu, Lifeng; Huan, Le; Huang, Fenglou; Cui, Yunliang; Lin, Zhaofen

    2016-12-01

    Seawater instillation-induced acute lung injury involves oxidative stress and apoptosis. Although hydrogen gas inhalation is reportedly protective in multiple types of lung injury, the effect of hydrogen gas inhalation on seawater instillation-induced acute lung injury remains unknown. This study investigated the effect of hydrogen gas on seawater instillation-induced acute lung injury and explored the mechanisms involved. Rabbits were randomly assigned to control, hydrogen (2 % hydrogen gas inhalation), seawater (3 mL/kg seawater instillation), and seawater + hydrogen (3 mL/kg seawater instillation + 2 % hydrogen gas inhalation) groups. Arterial partial oxygen pressure and lung wet/dry weight ratio were detected. Protein content in bronchoalveolar lavage fluid (BALF) and serum as well as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 levels were determined. Hematoxylin-eosin staining was used to monitor changes in lung specimens, and malondialdehyde (MDA) content and myeloperoxidase (MPO) activity were assayed. In addition, NF-E2-related factor (Nrf) 2 and heme oxygenase (HO)-1 mRNA and protein expression were measured, and apoptosis was assessed by measuring caspase-3 expression and using terminal deoxy-nucleotidyl transferase dUTP nick end-labeling (TUNEL) staining. Hydrogen gas inhalation markedly improved lung endothelial permeability and decreased both MDA content and MPO activity in lung tissue; these changes were associated with decreases in TNF-α, IL-1β, and IL-6 in BALF. Hydrogen gas also alleviated histopathological changes and cell apoptosis. Moreover, Nrf2 and HO-1 expressions were significantly activated and caspase-3 expression was inhibited. These results demonstrate that hydrogen gas inhalation attenuates seawater instillation-induced acute lung injury in rabbits and that the protective effects observed may be related to the activation of the Nrf2 pathway.

  12. Developing cell therapy techniques for respiratory disease: intratracheal delivery of genetically engineered stem cells in a murine model of airway injury

    Science.gov (United States)

    Leblond, Anne-Laure; Naud, Patrice; Forest, Virginie; Gourden, Clothilde; Sagan, Christine; Romefort, Bénédicte; Mathieu, Eva; Delorme, Bruno; Collin, Christine; Pagès, Jean-Christophe; Sensebé, Luc; Pitard, Bruno; Lemarchand, Patricia

    2009-01-01

    Over the past decade, interest has increased in the use of exogenous stem cells to optimize lung repair and serve as carriers of a therapeutic gene for genetic airway disease such as cystic fibrosis. We investigated the survival and the engraftment of exogenous stem cells after intratracheal injection, in a murine model of acute epithelial airway injury already used in gene therapy experiments on cystic fibrosis. Embryonic stem cells and mesenchymal stem cells were intratracheally injected 24hr after 2% polidocanol administration, when epithelial airway injury was maximal. Stem cells were transfected with reporter genes immediately prior to administration. Reporter gene expression was analyzed in trachea-lungs and bronchoalveolar lavages using non-fluorescent, quantitative and sensitive methods. ELISA quantitative results showed that 0.4 to 5.5% stem cells survived in the injured airway. Importantly, no stem cells survived in healthy airway or in the epithelial lining fluid. Using X-Gal staining, transduced mesenchymal stem cells were detected in injured trachea and bronchi lumen. When the epithelium was spontaneously regenerated, the in vivo amount of engrafted mesenchymal stem cells from cell line decreased dramatically. No stem cells from primary culture were located within lungs at 7 days. This study demonstrated the feasibility of the intratracheal cell delivery for airway diseases with acute epithelial injury. PMID:19606934

  13. The utilization of oropharyngeal intratracheal PAMP administration and bronchoalveolar lavage to evaluate the host immune response in mice.

    Science.gov (United States)

    Allen, Irving C

    2014-04-02

    The host immune response to pathogens is a complex biological process. The majority of in vivo studies classically employed to characterize host-pathogen interactions take advantage of intraperitoneal injections of select bacteria or pathogen associated molecular patterns (PAMPs) in mice. While these techniques have yielded tremendous data associated with infectious disease pathobiology, intraperitoneal injection models are not always appropriate for host-pathogen interaction studies in the lung. Utilizing an acute lung inflammation model in mice, it is possible to conduct a high resolution analysis of the host innate immune response utilizing lipopolysaccharide (LPS). Here, we describe the methods to administer LPS using nonsurgical oropharyngeal intratracheal administration, monitor clinical parameters associated with disease pathogenesis, and utilize bronchoalveolar lavage fluid to evaluate the host immune response. The techniques that are described are widely applicable for studying the host innate immune response to a diverse range of PAMPs and pathogens. Likewise, with minor modifications, these techniques can also be applied in studies evaluating allergic airway inflammation and in pharmacological applications.

  14. Irradiation embrittlement of ferritic stainless steels

    International Nuclear Information System (INIS)

    Suganuma, K.; Kayano, H.

    1984-01-01

    The characteristics of the irradiation embrittlement of some ferritic stainless steels were examined by tensile tests. Steels selected in this investigation were classified into three groups: chi phase, precipitation hardened Fe-13Cr steels; tempered martensitic Fe-12Cr steels; and low alloy steels. The latter steels were chosen in order to compare the irradiation embrittlement characteristics with those of stainless steels. The stainless steels were superior to the low alloy steels with regard to the irradiation embrittlement (the changes in both ductile-brittle transition temperature (DBTT) and unstable plastic flow transition temperature (UPFTT)), irrespective of whether these stainless steels had chi phase precipitated structures or tempered martensitic structures. The suppression of the DBTT increase owing to irradiation results from low yield stress increase Δσsub(y) and high |[dσsub(y)(u)/dT]|, where u denotes unirradiated, in the stainless steels. The suppression of the UPFTT results from the high work hardening rate or the high work exponent and the low Lueders strain in the stainless steels. These characteristics of irradiation embrittlement in the ferritic stainless steels are thought to be caused by the defect structure, which is modified by Cr atoms. (author)

  15. Development of new high-performance stainless steels

    International Nuclear Information System (INIS)

    Park, Yong Soo

    2002-01-01

    This paper focused on high-performance stainless steels and their development status. Effect of nitrogen addition on super-stainless steel was discussed. Research activities at Yonsei University, on austenitic and martensitic high-performance stainless, steels, and the next-generation duplex stainless steels were introduced

  16. Hydrogen damage in stainless steel

    International Nuclear Information System (INIS)

    Caskey, G.R. Jr.

    1981-01-01

    Hydrogen damage has been studied in a wide variety of stainless steels. Both internal and external hydrogen damage were evaluated by ductility or J-integral under rising tensile loads and by fractography. Analysis of the data has emphasized the potential effects of strain-induced martensite on hydrogen damage. Strain-induced martensite was neither necessary nor sufficient for hydrogen damage in the alloys studied. Neither ductility loss nor fracture-mode change correlated generally with martensite formation. Alloy composition, particularly nickel and nitrogen contents, was the primary factor in resistance to hydrogen damage. Thermomechanical processing, however, could alter the degree of hydrogen damage in an alloy and was critical for optimizing resistance to hydrogen damage. 10 figures, 10 tables

  17. Special stainless steels for sea water service

    International Nuclear Information System (INIS)

    Tomaselli, A.C.

    1983-01-01

    Very exacting demands are made on the corrosion resistance and mechanical properties of materials which in their service come into contact with seawater, and in many cases simultaneously with corrosive process solutions. The demand for higher alloy stainless steels for seawater application is rising in pace with the increasing requirements for safety and operation economy. The corrosion conditions in seawater and the resistance of stainless steels in this medium will be dealt with in the following. Sanicro 28 will then be compared with stainless steels, types AISI 304, 316 and 317, as well as with Alloy 20, Alloy 825 and SANDVIK 2RK65. (Author) [pt

  18. Recycle of radiologically contaminated austenitic stainless steels

    International Nuclear Information System (INIS)

    Imrich, K.J.; Leader, D.R.; Iyer, N.C.; Louthan, M.R. Jr.

    1995-01-01

    The United States Department of Energy owns large quantities of radiologically contaminated austenitic stainless steel which could by recycled for reuse if appropriate release standards were in place. Unfortunately, current policy places the formulation of a release standard for USA industry years, if not decades, away. The Westinghouse Savannah River Company, Idaho National Engineering Laboratory and various university and industrial partners are participating in initiative to recycle previously contaminated austenitic stainless steels into containers for the storage and disposal of radioactive wastes. This paper describes laboratory scale experiments which demonstrated the decontamination and remelt of stainless steel which had been contaminated with radionuclides

  19. Horizontal electron beam welding for stainless steels

    International Nuclear Information System (INIS)

    Martin, P.; Olivera, J.J.

    1977-01-01

    Stainless steel samples have been realized by local vacuum apparatus for electron beam welding applications to reactor core shell realizations. The best welding parameters have been determined by a systematic study. The welds have been characterized by mechanical tests [fr

  20. Consitutive modeling of metastable austenitic stainless steel

    NARCIS (Netherlands)

    Perdahcioglu, Emin Semih; Perdahcioglu, Emin Semih

    2008-01-01

    Metastable austenitic stainless steels combine high formability and high strength, which are generally opposing properties in materials. This property is a consequence of the martensitic phase transformation that takes place during deformation. This transformation is purely mechanically induced

  1. Stainless Steel to Titanium Bimetallic Transitions

    Energy Technology Data Exchange (ETDEWEB)

    Kaluzny, J. A. [Fermilab; Grimm, C. [Fermilab; Passarelli, D. [Fermilab

    2015-01-01

    In order to use stainless steel piping in an LCLS-II (Linac Coherent Light Source Upgrade) cryomodule, stainless steel to titanium bimetallic transitions are needed to connect the stainless steel piping to the titanium cavity helium vessel. Explosion bonded stainless steel to titanium transition pieces and bimetallic transition material samples have been tested. A sample transition tube was subjected to tests and x-ray examinations between tests. Samples of the bonded joint material were impact and tensile tested at room temperature as well as liquid helium temperature. The joint has been used successfully in horizontal tests of LCLS-II cavity helium vessels and is planned to be used in LCLS-II cryomodules. Results of material sample and transition tube tests will be presented.

  2. Intergenerational Transmission of Religious Giving: Instilling Giving Habits across the Life Course

    Directory of Open Access Journals (Sweden)

    Patricia Snell Herzog

    2016-07-01

    Full Text Available This paper investigates the research question: How do religious youth learn to give? While it is likely that youth learn religious financial giving from a variety of different sources, this investigation focuses primarily on how parents teach giving to their children. Supplementary data are also analyzed on the frequency in which youth hear extra-familial calls to give within their religious congregations. In focusing on parental transmission, the analysis identifies a number of approaches that parents report using to teach their children religious financial giving. It also investigates thoughts and feelings about religious financial giving by the children of these parents as a means of assessing the potential impacts of parental methods. Additionally, congregation member reflections on how they learned to give provide insights on giving as a process that develops across the life course, often instilled in childhood, but not appearing behaviorally until adulthood. As such, this paper contributes to a life course understanding of religious giving and has implications for giving across generations.

  3. Floating Hydrogel with Self-Generating Micro-Bubbles for Intravesical Instillation

    Directory of Open Access Journals (Sweden)

    Tingsheng Lin

    2016-12-01

    Full Text Available Intravesical instillation is the main therapy for bladder cancer and interstitial cystitis. However, most drug solutions are eliminated from bladder after the first voiding of urine. To solve this problem, we proposed a floating hydrogel with self-generating micro-bubbles as a new delivery system. It floated in urine, avoiding the urinary obstruction and bladder irritation that ordinary hydrogels caused. In this study, we abandoned traditional gas-producing method like chemical decomposition of NaHCO3, and used the foamability of Poloxamer 407 (P407 instead. Through simple shaking (just like shaking SonoVue for contrast-enhanced ultrasound in clinical, the P407 solution will “lock” many micro-bubbles and float in urine as quickly and steadily as other gas producing materials. In vivo release experiments showed that drug was released continually from hydrogel for 10 h during the erosion process. Thus, the residence time of drug in bladder was prolonged and drug efficacy was improved. In vivo efficacy study using rabbit acute bladder injury model showed that prolonged drug residence time in bladder increased the efficiency of heparin in the protection of bladder mucosal permeability. Therefore, our floating hydrogel system with self-generating micro-bubbles was single-component, simply prepared and efficacy enhancing, successfully exempting users from worries on safety and clinical efficiency from bench to bedside.

  4. Focal seizures after instillation of cyclomydril to a neonate with congenital CMV infection.

    Science.gov (United States)

    Hu, L; Dow, K

    2014-01-01

    We present the case of a term neonate who underwent a diagnostic eye examination on day one for possible genetic disorders. Five minutes after Cyclomydril (0.2% clyclopentolate and 1% phenylephrine) eye drops were instilled, a focal seizure lasting for approximately one hour occurred. The electroencephalograph (EEG) was normal but the magnetic resonance imaging (MRI) revealed calcifications in the bilateral periventricular regions. Urine CMV-DNA and maternal serum CMV-IgM were both positive. Auditory brainstem testing suggested severe sensoneural hearing loss. The baby was treated for congenital CMV infection and did not have further seizures. In this case the congenital CMV infection may have been the predisposing factor to central nervous system (CNS) toxicity induced by cyclopentolate. The exact mechanism is unknown but severe neurological impairment may be considered a contraindication for cyclopentolate eye drops in the neonate. To our knowledge, this is the first report of seizures occurring within the first week of life secondary to cyclomydril eye drops in a term neonate.

  5. Gel instillation sonohysterography (GIS) and saline contrast sonohysterography (SCSH): comparison of two diagnostic techniques.

    Science.gov (United States)

    Bij de Vaate, A J M; Brölmann, H A M; van der Slikke, J W; Emanuel, M H; Huirne, J A F

    2010-04-01

    To compare gel instillation sonohysterography (GIS) with saline contrast sonohysterography (SCSH) as diagnostic methods for the evaluation of the uterine cavity. A prospective cohort study was performed at the Department of Obstetrics and Gynecology of the VU University Medical Center, Amsterdam, between September 2007 and April 2008. We included 65 women suspected of having an intrauterine abnormality with an indication for SCSH/GIS. First SCSH and subsequently GIS were performed in all women. Distension of the uterine cavity, image quality, visualization of intrauterine abnormalities and pain experienced on a visual analog scale (VAS score) were recorded for both procedures. The mean distension with GIS was 9.0 mm and with SCSH it was 8.5 mm (P = 0.15). The mean image quality, on a scale from 0 to 5, for SCSH was 4.0 and for GIS it was 3.6 (P = 0.01). No difference was found for the visualization of intrauterine abnormalities, and the VAS scores for pain experienced on SCSH and GIS were 1.5 and 1.6, respectively (P = 0.62). The image quality of SCSH is slightly better than that of GIS. This difference is likely to be attributable to the presence of air bubbles in the gel. The small difference in uterine cavity distension in favor of GIS and comparable stable distension during at least 4 min make GIS a suitable alternative for SCSH if air bubbles can be prevented. Copyright 2009 ISUOG. Published by John Wiley & Sons, Ltd.

  6. Duplex stainless steel—Microstructure and properties

    Science.gov (United States)

    Debold, Terry A.

    1989-03-01

    Literature describing the microstructure of austenitic-ferritic stainless steels is reviewed, including phases which can be deleterious, such as σ and ά. The mechanical properties and corrosion resistance of Carpenter Technology's 7-Mo PLUSsr stainless (UNS S32950) demonstrate the resistance of this material to the formation of these phases and their deleterious effects. This material was evaluated in the annealed and welded conditions and after extended thermal treatments to simulate boiler and pressure vessel service.

  7. Preliminary Experience with Instillation of Triamcinolone Acetonide into the Urethra for Idiopathic Urethritis: A Prospective Pilot Study.

    Science.gov (United States)

    Ashraf, Junaid; Radford, Anna R; Turner, Alexander; Subramaniam, Ramnath

    2017-11-01

    Idiopathic bulbar urethritis (IBU) is characterized by hematuria ± dysuria without infection. Symptoms result from inflammation of the bulbar urethra, distal to external sphincter. IBU is difficult to manage and there is no recommended therapy. To determine whether instillation of triamcinolone acetonide is a useful treatment of IBU and its associated complications. Data were prospectively collected, for 22 months, on 14 consecutive patients presenting with terminal hematuria or blood spotting ± dysuria to a pediatric urology unit. Median age was 12 years (range: 10-15). Mean symptom duration was 13 months (range: 8-24). Normal baseline laboratory blood tests, urine cultures, and ultrasound assessments were seen in all; therefore, none were excluded on the basis of a known pathology. Follow-up telephone interviews, to assess symptom persistence and side effects, were performed at 6 weeks postintervention. The mean follow-up period was 15 months (range: 4-20). Visual confirmation of IBU was obtained cystoscopically and 40 mg of triamcinolone was instilled to the inflamed area under direct vision using an open-ended ureteral catheter. Symptoms resolution was the primary outcome. Repeat cystoscopic assessment ± triamcinolone instillation was recorded, as was the occurrence of complications. Seven patients (50%) required at least one further treatment. Overall complete or partial resolution was reported in 12/14 patients (85.7%). No side effects were reported. This small prospective series demonstrates that intraurethral instillation of triamcinolone seems to be a promising treatment option to alleviate inflammatory symptoms in majority of cases of idiopathic urethritis. Patient Summary: Fourteen boys with inflammation of the urethra, with no identifiable cause, were treated by topically triamcinolone, directly to the inflamed area. We demonstrate an 85.7% complete/partial resolution of symptoms with no side effects seen.

  8. Comparison of Outcomes for Normal Saline and an Antiseptic Solution for Negative-Pressure Wound Therapy with Instillation.

    Science.gov (United States)

    Kim, Paul J; Attinger, Christopher E; Oliver, Noah; Garwood, Caitlin; Evans, Karen K; Steinberg, John S; Lavery, Larry A

    2015-11-01

    Negative-pressure wound therapy with instillation is an adjunctive treatment that uses periodic instillation of a solution and negative pressure for a wide diversity of wounds. A variety of solutions have been reported, with topical antiseptics as the most frequently chosen option. The objective of this study was to compare the outcomes of normal saline versus an antiseptic solution for negative-pressure wound therapy with instillation for the adjunctive treatment of infected wounds. This was a prospective, randomized, effectiveness study comparing 0.9% normal saline versus 0.1% polyhexanide plus 0.1% betaine for the adjunctive treatment of infected wounds that required hospital admission and operative débridement. One hundred twenty-three patients were eligible, with 100 patients randomized for the intention-to-treat analysis and 83 patients for the per-protocol analysis. The surrogate outcomes measured were number of operative visits, length of hospital stay, time to final surgical procedure, proportion of closed or covered wounds, and proportion of wounds that remained closed or covered at the 30-day follow-up. There were no statistically significant differences in the demographic profiles in the two cohorts except for a larger proportion of male patients (p = 0.004). There was no statistically significant difference in the surrogate outcomes with the exception of the time to final surgical procedure favoring normal saline (p = 0.038). The authors' results suggest that 0.9% normal saline may be as effective as an antiseptic (0.1% polyhexanide plus 0.1% betaine) for negative-pressure wound therapy with instillation for the adjunctive inpatient management of infected wounds. Therapeutic, II.

  9. Radioautographic identification of central monoaminergic neurons after local micro-instillation of tritiated serotonin and norepinephrine in the cat

    International Nuclear Information System (INIS)

    Leger, Lucienne; Mouren-Mathieu, A.-M.; Descarries, Laurent.

    1978-01-01

    Monoaminergic neurons in nuclei raphe dorsalis and locus coeruleus of the cat may be visualized by radioautography after local micro-instillation of tritiated serotonin and noradrenaline. The concomitant administration of the appropriate tracer with the other biogenic amine in non radioactive form permits a specific identification of serotoninergic and catecholaminergic nerve cell bodies. A small contingent of presumptive serotoninergic neurons is thus demonstrated in the region of the locus coeruleus [fr

  10. Is intravesical instillation of hyaluronic acid and chondroitin sulfate useful in preventing recurrent bacterial cystitis? A multicenter case control analysis

    OpenAIRE

    Giorgio Gugliotta; Gloria Calagna; Giorgio Adile; Salvatore Polito; Salvatore Saitta; Patrizia Speciale; Stefano Palomba; Antonino Perino; Roberta Granese; Biagio Adile

    2015-01-01

    Objective: Urinary tract infections (UTIs) are common in the female population and, over a lifetime, about half of women have at least one episode of UTI requiring antibiotic therapy. The aim of the current study was to compare two different strategies for preventing recurrent bacterial cystitis: intravesical instillation of hyaluronic acid (HA) plus chondroitin sulfate (CS), and antibiotic prophylaxis with sulfamethoxazole plus trimethoprim. Materials and methods: This was a retrospective...

  11. Tumor associated macrophages polarization dictates the efficacy of BCG instillation in non-muscle invasive urothelial bladder cancer.

    Science.gov (United States)

    Suriano, Francesca; Santini, Daniele; Perrone, Giuseppe; Amato, Michela; Vincenzi, Bruno; Tonini, Giuseppe; Muda, Andrea; Boggia, Sara; Buscarini, Maurizio; Pantano, Francesco

    2013-11-05

    To evaluate the prognostic role of TAMs in patients affected by non-muscle invasive bladder cancer (NMIBC), undergone Trans Urethral Resection of Bladder (TURB) and Bacillus Calmette-Guerin (BCG) therapy. Data from 40 patients (36 men, 4 women), mean age 69 years (40-83 years), treated for NMIBC with TURB and BCG instillation were collected. Two different groups were considered: group with and group without bladder cancer recurrence. Correlations between immunofluorescence measured Mtot, M1 and M2 infiltration and clinicopathological parameters were evaluated using Spearman and Mann-Whitney methods. The recurrence-free survival rate was calculated using the Kaplan-Meier method. CD68 positive cells (Mtot) were observed in all specimens tested. High Mtot, M1 and M2 infiltration was observed in patients with disease recurrence, even before endovescical BCG instillation. Significant value for M2 infiltration (p = 0,042) was found calculating significativity between two group medians before BCG therapy. p = 0,072 and p = 0,180 were observed correlating median of Mtot and M1 between two groups of patients respectively. Values of p = 0,44, p = 0,23 and p = 0,64 from correlation between DFS and Mtot, M1 and M2 median in patients before endovescical BCG instillation, were calculated respectively. Comparing DFS and Mtot, M1 and M2 median in patients group after endovescical BCG instillation significant values were obtained (p = 0,020; p = 0,02; and p = 0,029 respectively). M2 tumor infiltration could be a prognostic value of recurrence in patients with NMIBC.

  12. Effect of Kushen injection in combined with continuing nursing on the patients with instillation therapy after bladder cancer surgery

    Directory of Open Access Journals (Sweden)

    Rui-Xia Han

    2016-07-01

    Full Text Available Objective: To observe the effect of Kushen injection in combined with continuing nursing on the patients with instillation therapy after bladder cancer surgery. Methods: A total of 60 patients with bladder cancer who were admitted in our hospital from January, 2013 to January, 2015 for instillation therapy were included in the study and were randomized into the observation group and the control group. The patients in the two groups were given routine THP instillation therapy. On this basis, the patients in the observation group were given additional Kushen injection in combined with continuing nursing. The occurrence rate of adverse reactions during the chemotherapy period and the improvement of immunological indicators in the two groups were compared. SF-36 health survey scale was used to evaluate the living qualities. Results: After treatment, CD4+ and NK cell level in the observation group were significantly elevated, but CD8+ level was significantly reduced when compared with before treatment. CD4+, CD8+, and NK cell levels after treatment in the control group were not significantly different from those before treatment. The bladder irritation symptoms during the chemotherapy period in the observation group were significantly lighter than those in the control group. The occurrence rate of main adverse reactions during the chemotherapy period in the observation group was significantly lower than that in the control group. The living quality scores in the observation group were significantly higher than those in the control group. Conclusions: Kushen injection in combined with continuing nursing can effectively regulate the immunological function in patients with instillation therapy after bladder cancer surgery, reduce the occurrence rate of adverse reactions, and enhance the living qualities.

  13. A comparison between bupivacaine instillation versus ilioinguinal/iliohypogastric nerve block for postoperative analgesia following inguinal herniorrhaphy in children.

    Science.gov (United States)

    Casey, W F; Rice, L J; Hannallah, R S; Broadman, L; Norden, J M; Guzzetta, P

    1990-04-01

    This study compared the postoperative pain relief provided by simple instillation of bupivacaine into a hernia wound with that provided by ilioinguinal/iliohypogastric (IG/IH) nerve block. Sixty children undergoing inguinal hernia repair under general anesthesia were randomized to receive 0.25 ml/kg of 0.25% bupivacaine for either IG/IH nerve block or up to 0.5 ml/kg of the same solution for instillation nerve blocks. In the postanesthesia care unit (PACU), a trained blinded observer evaluated the patient's level of postoperative pain using a standardized 10-point objective pain scale. Fentanyl 1-2 micrograms/kg was administered intravenously to any child scoring 6 or more points on the pain scale. The difference in pain scores among the two groups were compared. The two groups were not significantly different in age, duration of surgery, or anesthesia. There was no significant difference between patients who received the two treatment modalities in their pain scores, analgesic requirements in the PACU, recovery times, and discharge times. These results demonstrate that the simple instillation of local anesthetics into a wound provides postoperative pain relief following hernia repair, which is as effective as that provided by intraoperative IG/IH nerve block.

  14. Is intravesical instillation of hyaluronic acid and chondroitin sulfate useful in preventing recurrent bacterial cystitis? A multicenter case control analysis.

    Science.gov (United States)

    Gugliotta, Giorgio; Calagna, Gloria; Adile, Giorgio; Polito, Salvatore; Saitta, Salvatore; Speciale, Patrizia; Palomba, Stefano; Perino, Antonino; Granese, Roberta; Adile, Biagio

    2015-10-01

    Urinary tract infections (UTIs) are common in the female population and, over a lifetime, about half of women have at least one episode of UTI requiring antibiotic therapy. The aim of the current study was to compare two different strategies for preventing recurrent bacterial cystitis: intravesical instillation of hyaluronic acid (HA) plus chondroitin sulfate (CS), and antibiotic prophylaxis with sulfamethoxazole plus trimethoprim. This was a retrospective review of two different cohorts of women affected by recurrent bacterial cystitis. Cases (experimental group) were women who received intravesical instillations of a sterile solution of high concentration of HA + CS in 50 mL water with calcium chloride every week during the 1(st) month and then once monthly for 4 months. The control group included women who received traditional therapy for recurrent cystitis based on daily antibiotic prophylaxis using sulfamethoxazole 200 mg plus trimethoprim 40 mg for 6 weeks. Ninety-eight and 76 patients were treated with experimental and control treatments, respectively. At 12 months after treatment, 69 and 109 UTIs were detected in the experimental and control groups, respectively. The proportion of patients free from UTIs was significantly higher in the experimental than in the control group (36.7% vs. 21.0%; p = 0.03). Experimental treatment was well tolerated and none of the patients stopped it. The intravesical instillation of HA + CS is more effective than long-term antibiotic prophylaxis for preventing recurrent bacterial cystitis. Copyright © 2015. Published by Elsevier B.V.

  15. CT-guided lung biopsy: incidence of pneumothorax after instillation of NaCl into the biopsy track

    Energy Technology Data Exchange (ETDEWEB)

    Billich, Christian; Brenner, Gerhard; Schmidt, Stefan A.; Brambs, Hans-Juergen; Pauls, Sandra [University of Ulm, Department of Diagnostic and Interventional Radiology, Ulm (Germany); Muche, Rainer [University of Ulm, Institute of Biometrics, Ulm (Germany); Krueger, Stefan [University of Ulm, Department of Internal Medicine, Ulm (Germany)

    2008-06-15

    This study was conducted to evaluate whether instillation of NaCl 0.9% solution into the biopsy track reduces the incidence of pneumothoraces after CT-guided lung biopsy. A total of 140 consecutive patients with pulmonary lesions were included in this prospective study. All patients were alternatingly assigned to one of two groups: group A in whom the puncture access was sealed by instillation of NaCl 0.9% solution during extraction of the guide needle (n = 70) or group B for whom no sealing was performed (n = 70). CT-guided biopsy was performed with a 18-G coaxial system. Localization of lesion (pleural, peripheral, central), lesion size, needle-pleural angle, rate of pneumothorax and alveolar hemorrhage were evaluated. In group A, the incidence of pneumothorax was lower compared to group B (8%, 6/70 patients vs. 34%, 24/70 patients; P < 0.001). All pneumothoraces occurred directly post punctionem after extraction of the guide needle. One patient in group A and eight patients in group B developed large pneumothoraces requiring chest tube placement (P = 0.01). The frequency of pneumothorax was independent of other variables. After CT-guided biopsy, instillation of NaCl 0.9% solution into the puncture access during extraction of the needle significantly reduces the incidence of pneumothorax. (orig.)

  16. Current status of stainless steel industry and development of stainless steel

    International Nuclear Information System (INIS)

    Lee, Yong Deuk; Lee, Chan Soo; Kim Kwang Tae

    2000-01-01

    Stainless steel is not only clean and smooth in its surface, but also it is superior in quality in terms of corrosion resistance and strength. So that, it is widely in use in the field of construction, chemical installations, and other industries. Growth of stainless steel industry started since the steel technology was developed for mass production in 1960s. Since then stainless steel industry grew rapidly on account of diversified development in this field and growth rate went up to 5.8% per year comparable to 2.3% of steel growth. The rapid growth is attributed to significant industry developments in Europe and Japan in the years of 1970s and 1980s. In addition to these the expansion of stainless steel industry in Korea and Taiwan. Presently Korea produces about 120,000 tons of stainless steel and occupies about 8% of international market. This means Korea become the second largest single country in world in stainless steel production. Moreover Korea is to reinforce its domestic production line by affiliating production companies, increasing of production capability, and specializing in types of stainless steel. This paper is to describe activity of material development, and types of stainless steel for industry use. (Hong, J. S.)

  17. TEACHERS AND EDUCATION OF CHARACTER INSTILLATION (Research Result at Private Elementary School of Muhammadiyah in Medan

    Directory of Open Access Journals (Sweden)

    Amini

    2018-04-01

    Full Text Available Teachers are the most important element in the development of character education in elementary school, because it becomes the main foundation for a child. Therefore character education made a continuous process to produce a future human figure rooted in the cultural values of the Indonesian nation. Character education in the current context is very relevant to students to tackle the ongoing moral crisis in our country, including free association, crime against friends, teenage theft, cheating, drug abuse and drugs, pornography, brawls, and others. This is based on the results of research on SDS Muhammadiyah about teacher and character education education. The research methodology was conducted with qualitative descriptive analysis. Data obtained based on interviews, observation, and study documentation with the object of research. The result of the research shows that character education education in SDS Muhammadiyah 29 Medan City is contained in all subjects and outside subjects that are instilled early on by all teachers. Cultivation of character education conducted in all subjects through 3 content, ie general content (PAI, PKn, IPS, IPA, Bahasa Indonesia, Mathematics, Arts and Culture, special content (Kemuhammadiyahan, and Local Content (Malay Arabic / Arabic, English, Computer. Character education model performed outside the subjects through 4 things, namely: religious habituation (religious, discipline exercises, fun activities, and sports activities. Commonalities include (the implementation of Zuhr prayers bertamaaah, dhuha congregation, tadarus Al-Qur'an and memorizing the verses of Al-Qur'an, and culture shake. Discipline includes (the existence of rules and school rules and liaison books every day. Kewiraaan include (Flag ceremony and Hizbul wathan. Exercise includes (physical fitness exercise.

  18. Analysis of Japanese Patients Treated with or without Long-Term Epirubicin Plus Ara-C Intravesical Instillation Therapy for Low-Grade Superficial Bladder Cancer

    Directory of Open Access Journals (Sweden)

    Tomonori Kato

    2015-01-01

    Full Text Available The high incidence of tumor recurrence following transurethral resection (TUR represents a major problem encountered in the management of bladder cancer. This study examined the efficacy of intravesical chemotherapy in superficial bladder cancer. We retrospectively analyzed 90 Japanese cases with low-grade superficial transitional cell carcinoma (stage T1, grades 1 and 2 who were rendered tumor-free by TURBT (TUR of bladder tumor and who thereafter were treated with or without intravesical chemotherapy. Among them, instillation was terminated in 2 patients due to adverse effects (severe but reversible chemical cystitis. Remaining 88 patients were divided into 2 groups according to therapy: the TURBT-only group (n=46, defined as patients treated with TURBT alone, and the Instillation group (n=42, defined as patients treated with weekly intravesical instillation therapies using epirubicin plus Ara-C. Recurrence-free rate was significantly higher in the Instillation group than in the TURBT-only group (p=0.02, HR = 0.457. The 5-year recurrence-free rate was 58.5% for the Instillation group and 38.6% for the TURBT-only group. Our instillation schedule represents the most intensive regimen among previously reported therapies and resulted in a 54.3% decrease in incidence of tumor recurrence. We believe that the results of this study could provide useful information on management of bladder cancer.

  19. Effect of nasal instillation of female urine or vaginal exudate on serum cortisol and prolactin levels in isolated and anesthetized male rhesus monkeys (Macaca mulatta).

    Science.gov (United States)

    Mora, O A; García Castiñeiras, S; Ezquerra, C; Guisado, S

    1991-01-01

    Two male adult rhesus monkeys were used and caged individually. The room was temperature-controlled having a light-dark period of 12/12 hours. The animals were rapidly immobilized and immediately anesthetized with ketamine i. m. (10 mg/kg of body weight). They were bled four times at 15, 30, 45 and 60 mins after the ketamine injection, twice a week for 6 weeks. When necessary, maintenance doses of ketamine were administered. The serum levels of cortisol and prolactin after nasal instillation of a suspension of vaginal exudate showed lower values than in control conditions (nasal instillation of saline). The control levels of cortisol tended to increase up to 60 mins, whilst in experimental conditions (nasal instillation of female urine or vaginal exudate) did not show such an increase. Cortisol remained similar during the sampling and similar to the 15 mins control levels, but the difference is statistically significant only after instillation of vaginal exudate as compared with control. The levels of prolactin did not show significant variations during sampling either in control or after female urine instillation. However, the instillation of vaginal exudate decreased the prolactin levels at 15 mins which tended to recover the control levels up to 60 mins. These results support the hypothesis, discussed in a previous paper, that some chemical information from females suppresses or mitigates the effect of acute stress resulting from handling the animals before anesthesia.

  20. Effects of intratracheal administration of nuclear factor-kappaB decoy oligodeoxynucleotides on long-term cigarette smoke-induced lung inflammation and pathology in mice

    OpenAIRE

    Li, Yu-Tao; He, Bei; Wang, Yu-Zhu; Wang, Jing

    2009-01-01

    Abstract To determine if nuclear factor-κB (NF-κB) activation may be a key factor in lung inflammation and respiratory dysfunction, we investigated whether NF-κB can be blocked by intratracheal administration of NF-κB decoy oligodeoxynucleotides (ODNs), and whether decoy ODN-mediated NF-κB inhibition can prevent smoke-induced lung inflammation, respiratory dysfunction, and improve pathological alteration in the small airways and lung parenchyma in the long-term smoke-induced mouse model syste...

  1. Ion-nitriding of austenitic stainless steels

    International Nuclear Information System (INIS)

    Pacheco, O.; Hertz, D.; Lebrun, J.P.; Michel, H.

    1995-01-01

    Although ion-nitriding is an extensively industrialized process enabling steel surfaces to be hardened by nitrogen diffusion, with a resulting increase in wear, seizure and fatigue resistance, its direct application to stainless steels, while enhancing their mechanical properties, also causes a marked degradation in their oxidation resistance. However, by adaption of the nitriding process, it is possible to maintain the improved wear resistant properties while retaining the oxidation resistance of the stainless steel. The controlled diffusion permits the growth of a nitrogen supersaturated austenite layer on parts made of stainless steel (AISI 304L and 316L) without chromium nitride precipitation. The diffusion layer remains stable during post heat treatments up to 650 F for 5,000 hrs and maintains a hardness of 900 HV. A very low and stable friction coefficient is achieved which provides good wear resistance against stainless steels under diverse conditions. Electrochemical and chemical tests in various media confirm the preservation of the stainless steel characteristics. An example of the application of this process is the treatment of Reactor Control Rod Cluster Assemblies (RCCAs) for Pressurized Water Nuclear Reactors

  2. Aging degradation of cast stainless steel

    International Nuclear Information System (INIS)

    Chopra, O.K.; Chung, H.M.

    1985-10-01

    A program is being conducted to investigate the significance of in-service embrittlement of cast-duplex stainless steels under light-water reactor operating conditions. Data from room-temperature Charpy-impact tests for several heats of cast stainless steel aged up to 10,000 h at 350, 400, and 450 0 C are presented and compared with results from other studies. Microstructures of cast-duplex stainless steels subjected to long-term aging either in the laboratory or in reactor service have been characterized. The results indicate that at least two processes contribute to the low-temperature embrittleent of duplex stainless steels, viz., weakening of the ferrite/austenite phase boundary by carbide precipitation and embrittlement of ferrite matrix by the formation of additional phases such as G-phase, Type X, or the α' phase. Carbide precipitation has a significant effect on the onset of embrittlement of CF-8 and -8M grades of stainless steels aged at 400 or 450 0 C. The existing correlations do not accurately represent the embrittlement behavior over the temperature range 300 to 450 0 C. 18 refs., 13 figs

  3. HTPro: Low-temperature Surface Hardening of Stainless Steel

    DEFF Research Database (Denmark)

    Christiansen, Thomas Lundin; Somers, Marcel A. J.

    2013-01-01

    Low-temperature surface hardening of stainless steel provides the required performance properties without affecting corrosion resistance.......Low-temperature surface hardening of stainless steel provides the required performance properties without affecting corrosion resistance....

  4. 77 FR 64545 - Drawn Stainless Steel Sinks From China

    Science.gov (United States)

    2012-10-22

    ... merchandise as ``drawn stainless steel sinks with single or multiple drawn bowls, with or without drain boards... finishing the vertical corners to form the bowls. Stainless steel sinks with fabricated bowls may sometimes...

  5. Intratracheal Seal Disc

    DEFF Research Database (Denmark)

    Christiansen, Karen J; Moeslund, Niels; Lauridsen, Henrik

    2017-01-01

    21, CT was repeated before euthanasia. The trachea and epidermis were excised en bloc for histopathological evaluation. RESULTS: Insertion and correct placement of the disc was unproblematic in all animals. CT at day 14 confirmed a clear airway, appropriate placement of the disc, and full closure...

  6. Phosphate coating on stainless steel 304 sensitized

    International Nuclear Information System (INIS)

    Cruz V, J. P.; Vite T, J.; Castillo S, M.; Vite T, M.

    2009-01-01

    The stainless steel 304 can be sensitized when welding processes are applied, that causes the precipitation of chromium carbide in the grain limits, being promoted in this way the formation of galvanic cells and consequently the corrosion process. Using a phosphate coating is possible to retard the physiochemical damages that can to happen in the corrosion process. The stainless steel 304 substrate sensitized it is phosphate to base of Zn-Mn, in a immersion cell very hot. During the process was considered optimization values, for the characterization equipment of X-rays diffraction and scanning electron microscopy was used. The XRD technique confirmed the presence of the phases of manganese phosphate, zinc phosphate, as well as the phase of the stainless steel 304. When increasing the temperature from 60 to 90 C in the immersion process a homogeneous coating is obtained. (Author)

  7. Ultrasonic testing of austenitic stainless steel welds

    International Nuclear Information System (INIS)

    Nishino, Shunichi; Hida, Yoshio; Yamamoto, Michio; Ando, Tomozumi; Shirai, Tasuku.

    1982-05-01

    Ultrasonic testing of austenitic stainless steel welds has been considered difficult because of the high noise level and remarkable attenuation of ultrasonic waves. To improve flaw detectability in this kind of steel, various inspection techniques have been studied. A series of tests indicated: (1) The longitudinal angle beam transducers newly developed during this study can detect 4.8 mm dia. side drilled holes in dissimilar metal welds (refraction angle: 55 0 from SUS side, 45 0 from CS side) and in cast stainless steel welds (refraction angle: 45 0 , inspection frequency: 1 MHz). (2) Cracks more than 5% t in depth in the heat affected zones of fine-grain stainless steel pipe welds can be detected by the 45 0 shear wave angle beam method (inspection frequency: 2 MHz). (3) The pattern recognition method using frequency analysis technology was presumed useful for discriminating crack signals from spurious echoes. (author)

  8. Stainless Steel Microstructure and Mechanical Properties Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Switzner, Nathan T

    2010-06-01

    A nitrogen strengthened 21-6-9 stainless steel plate was spinformed into hemispherical test shapes. A battery of laboratory tests was used to characterize the hemispheres. The laboratory tests show that near the pole (axis) of a spinformed hemisphere the yield strength is the lowest because this area endures the least “cold-work” strengthening, i.e., the least deformation. The characterization indicated that stress-relief annealing spinformed stainless steel hemispheres does not degrade mechanical properties. Stress-relief annealing reduces residual stresses while maintaining relatively high mechanical properties. Full annealing completely eliminates residual stresses, but reduces yield strength by about 30%.

  9. Pulmonary pharmacokinetics of tulathromycin in swine. Part I: Lung homogenate in healthy pigs and pigs challenged intratracheally with lipopolysaccharide of Escherichia coli.

    Science.gov (United States)

    Villarino, N; Lesman, S; Fielder, A; García-Tapia, D; Cox, S; Lucas, M; Robinson, J; Brown, S A; Martín-Jiménez, T

    2013-08-01

    The objective of the study was to assess the pharmacokinetics of tulathromycin in lung tissue homogenate (LT) and plasma from healthy and lipopolysaccharide (LPS)-challenged pigs. Clinically healthy pigs were allocated to two dosing groups of 36 animals each (group 1 and 2). All animals were treated with tulathromycin (2.5 mg/kg). Animals in group 2 were also challenged intratracheally with LPS from Escherichia coli (LPS-Ec) 3 h prior to tulathromycin administration. Blood and LT samples were collected from all animals during 17-day post-tulathromycin administration. For LT, one sample from the middle (ML) and caudal lobes (CL) was taken. The concentration of tulathromycin was significantly lower in the ML after the intratracheal administration of LPS-E. coli (P lungs was rapid and persisted at high levels for 17-day postadministration. The distribution of the drug within the lung seems to be homogenous, at least between the middle and caudal lobes within dosing groups. The concentration versus time profile of the drug and pharmacokinetic parameters in two different lung areas (middle and caudal lobe) were consistent within the groups. The clinical significance of these findings is unknown. © 2012 John Wiley & Sons Ltd.

  10. 77 FR 1504 - Stainless Steel Wire Rod From India

    Science.gov (United States)

    2012-01-10

    ... COMMISSION Stainless Steel Wire Rod From India Determination On the basis of the record \\1\\ developed in the... antidumping duty order on stainless steel wire rod From India would be likely to lead to continuation or... contained in USITC Publication 4300 (January 2012), entitled Stainless Steel Wire Rod From India...

  11. Low temperature gaseous surface hardening of stainless steel

    DEFF Research Database (Denmark)

    Christiansen, Thomas; Somers, Marcel A. J.

    2010-01-01

    The present contribution gives an overview of some of the technological aspects of low temperature thermochemical treatment of stainless steel. Examples of low temperature gaseous nitriding, carburising and nitrocarburising of stainless steel are presented and discussed. In particular......, the morphology, microstructure and characteristics of so-called expanite “layers” on stainless steel are addressed....

  12. Low temperature gaseous surface hardening of stainless steel

    DEFF Research Database (Denmark)

    Christiansen, Thomas; Somers, Marcel A. J.

    2011-01-01

    The present contribtion gives an overview of some of the technological aspects of low temperature thermochemical treatment of stainless steel. Examples of low temperature gaseous nitriding, carburising and nitrocarburising of stainless steel are presented and discussed. In particular......, the morphology, microstructure and characteristics of so-called expanded austenite "layers" on stainless steel are addressed....

  13. 21 CFR 872.3350 - Gold or stainless steel cusp.

    Science.gov (United States)

    2010-04-01

    ...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3350 Gold or stainless steel cusp. (a) Identification. A gold or stainless steel cusp is a prefabricated device made of austenitic alloys or alloys containing 75 percent or greater gold and metals of the platinum group or stainless steel intended to provide...

  14. 78 FR 21417 - Drawn Stainless Steel Sinks From China

    Science.gov (United States)

    2013-04-10

    ... COMMISSION Drawn Stainless Steel Sinks From China Determinations On the basis of the record \\1\\ developed in... drawn stainless steel sinks from China, provided for in subheading 7324.10.00 of the Harmonized Tariff... notification of a preliminary determinations by Commerce that imports of drawn stainless steel sinks from China...

  15. Bladder instillation of Escherichia coli lipopolysaccharide alters the muscle contractions in rat urinary bladder via a protein kinase C-related pathway

    International Nuclear Information System (INIS)

    Weng, T.I.; Chen, W.J.; Liu, S.H.

    2005-01-01

    Uropathogenic Escherichia coli is a common cause of urinary tract infection. We determined the effects of intravesical instillation of E. coli lipopolysaccharide (LPS, endotoxin) on muscle contractions, protein kinase C (PKC) translocation, and inducible nitric oxide synthase (iNOS) expression in rat urinary bladder. The contractions of the isolated rat detrusor muscle evoked by electrical field stimulations were measured short-term (1 h) or long-term (24 h) after intravesical instillation of LPS. One hour after LPS intravesical instillation, bladder PKC-α translocation from cytosolic fraction to membrane fraction and endothelial (e)NOS protein was elevated, and detrusor muscle contractions were significantly increased. PKC inhibitors chelerythrine and Ro32-0432 inhibited this LPS-enhanced contractile response. Application of PKC activator β-phorbol-12,13-dibutyrate enhanced the muscle contractions. Three hours after intravesical instillation of LPS, iNOS mRNA was detected in the bladder. Immunoblotting study also demonstrated that the induction of iNOS proteins is detected in bladder in which LPS was instilled. 24 h after intravesical instillation of LPS, PKC-α translocation was impaired in the bladder; LPS did not affect PKC-δ translocation. Muscle contractions were also decreased 24 h after LPS intravesical instillation. Aminoguanidine, a selective iNOS inhibitor, blocked the decrease in PKC-α translocation and detrusor contractions induced by LPS. These results indicate that there are different mechanisms involved in the alteration of urinary bladder contractions after short-term and long-term treatment of LPS; an iNOS-regulated PKC signaling may participate in causing the inhibition of muscle contractions in urinary bladder induced by long-term LPS treatment

  16. Potential health impact on mice after nasal instillation of nano-sized copper particles and their translocation in mice.

    Science.gov (United States)

    Liu, Yang; Gao, Yuxi; Zhang, Lili; Wang, Tiancheng; Wang, Jiangxue; Jiao, Fang; Li, Wei; Liu, Ying; Li, Yufeng; Li, Bai; Chai, Zhifang; Wu, Gang; Chen, Chunying

    2009-11-01

    The purpose of this study is to evaluate the overall toxicity of nasal instilled nanoscale copper particles (23.5 nm) in mice. Pathological examination, target organs identification, and blood biochemical assay of experimental mice were carried out in comparison with micro-sized copper particles (17 microm). However, only in the high-dose group of copper nanoparticles (40 mg/kg body weight instilled for three times in one week), the body weight of mice were retarded and significant pathological changes were observed. There were hydropic degeneration around the central vein and the spotty necrosis of hepatocytes in the liver and swelling in the renal glomerulus, while, severe lesion associated with the decreased number of olfactory cells and the dilapidated laminated structure were also observed in the olfactory bulb. The serum biochemical assay also indicated the sign of renal and hepatic lesion. However, there were no obvious pathological and physiological damages in the mice after instilling different-sized copper nanoparticles with low dose of 1 mg/kg body weight. The retention and distribution of copper in various tissues show that the liver, kidneys and olfactory bulb are the main accumulated tissues for copper particles, which were determined by high sensitive element-specific technique of ICP-MS. The copper contents of the liver, kidneys and the olfactory bulb increase significantly at the group of 40 mg/kg compared to the control group, which is in agreement with the histological changes. Therefore, the data indicate that nasal inhaled copper particles at very high dosage can translocate to other organs and tissues and further induce certain lesions. The present results are helpful to get better understanding of the risk assessment and evaluation for copper nanoparticles.

  17. Intravesical instillation of hyaluronic acid prolonged the effect of bladder hydrodistention in patients with severe interstitial cystitis.

    Science.gov (United States)

    Shao, Yuan; Shen, Zhou-Jun; Rui, Wen-Bin; Zhou, Wen-Long

    2010-03-01

    To evaluate the efficacy of intravesical instillation of hyaluronic acid (HA) after hydrodistention for the treatment of patients with interstitial cystitis (IC) having small bladder capacity. A total of 47 patients with IC (aged 27-76 years) whose functional bladder capacity was less than 200 mL received bladder hydrodistention. Thereafter, 20 patients received intravesical instillation of 40 mg HA weekly in the first month and then monthly in the following 2 months. Sixteen patients received intravesical heparin instead and 11 patients received hydrodistention alone as the control. Mean voids per day, visual analog scale for pain, and functional bladder capacity were measured before hydrodistention and 3 and 6 months after hydrodistention in all 3 groups and 9 months after hydrodistention in HA and heparin groups. Two patients in the HA group and 1 in the heparin group failed to complete the treatment. Three months after hydrodistention, there was no improvement in the control group. Six and 9 months after hydrodistention, rate of improvement was significantly higher in the HA group than in the heparin group (77.8% vs 33.3%, P < .05; 50% vs 20%, P < .05). At 9 months, heparin treatment did not show any improvement. Improvement in voids per day (-1.8 +/- 2.5, P < .01), visual analog scale (-0.9 +/- 1.1, P < .01), and bladder capacity (16 +/- 18 mL, P < .01) was still significant in the HA group. Intravesical instillation of HA may obviously prolong the effect of bladder hydrodistention in patients with severe IC. Its effect was better than heparin. 2010 Elsevier Inc. All rights reserved.

  18. DNA Damage Following Pulmonary Exposure by Instillation to Low Doses of Carbon Black (Printex 90) Nanoparticles in Mice

    DEFF Research Database (Denmark)

    Kyjovska, Zdenka O.; Jacobsen, Nicklas R.; Saber, Anne T.

    2015-01-01

    We previously observed genotoxic effects of carbon black nanoparticles at low doses relative to the Danish Occupational Exposure Limit (3.5 mg/m3). Furthermore, DNA damage occurred in broncho-alveolar lavage (BAL) cells in the absence of inflammation, indicating that inflammation is not required...... for the genotoxic effects of carbon black. In this study, we investigated inflammatory and acute phase response in addition to genotoxic effects occurring following exposure to nanoparticulate carbon black (NPCB) at even lower doses. C57BL/6JBomTac mice were examined 1, 3, and 28 days after a single instillation...

  19. Integrated analytical techniques with high sensitivity for studying brain translocation and potential impairment induced by intranasally instilled copper nanoparticles.

    Science.gov (United States)

    Bai, Ru; Zhang, Lili; Liu, Ying; Li, Bai; Wang, Liming; Wang, Peng; Autrup, Herman; Beer, Christiane; Chen, Chunying

    2014-04-07

    Health impacts of inhalation exposure to engineered nanomaterials have attracted increasing attention. In this paper, integrated analytical techniques with high sensitivity were used to study the brain translocation and potential impairment induced by intranasally instilled copper nanoparticles (CuNPs). Mice were exposed to CuNPs in three doses (1, 10, 40 mg/kg bw). The body weight of mice decreased significantly in the 10 and 40 mg/kg group (ptechniques for systematic investigations is a promising direction to better understand the biological activities of nanomaterials. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  20. Quantitative Comparison of the Effect of 10% Phenylephrine Instillation and Manual Elevation in Patients with Involutional Blepharoptosis.

    Science.gov (United States)

    Pereira, Ivana Cardoso; Matayoshi, Suzana

    2017-01-01

    To compare the effect of 10% phenylephrine (PE) instillation and manual elevation (ME) on the upper eyelid position of the tested eye and the contralateral eye in patients with involutional blepharoptosis (IB). IB patients were submitted to two tests followed by observation of the effect on the contralateral eyelid: (1) ME of the more ptotic eyelid; and (2) instillation of two drops of 10% PE (phenylephrine test) in the more ptotic eye. The patients were filmed before and 5, 10, and 15 minutes after instillation. The upper eyelid margin reflex distance (MRD1) was measured using the software Image J, and the results were analyzed with the linear mixed-effects model. The study included 70 patients aged 44-86 years, 64 of whom were female (91.43%), divided into three groups: subjects with unilateral IB, subjects with bilateral IB, and controls. The eye submitted to instillation with 10% PE displayed significant elevation during the first 10 min: from 1.33 ± 0.66 mm to 2.06 ± 0.89 mm (unilateral group), from 1.26 ± 0.63 mm to 2.29 ± 0.86 mm (bilateral group), and from 3.12 ± 0.68 mm to 4.06 ± 0.92 mm (control group). MRD1 decreased in the contralateral eye in IB patients, significantly more so after the phenylephrine test: PE vs. ME = 18.9% versus 17.2% reduction in the unilateral group, and 13.6% versus 10.7% reduction in the bilateral group. The outcome was not influenced by IB severity and the concurrence of IB and eye dominance. Both ME and 10% PE affected the contralateral upper eyelid, but the response was significantly better with the latter.

  1. Modelling the material behaviour of metastable stainless

    NARCIS (Netherlands)

    Datta, K.; Geijselaers, Hubertus J.M.; Post, J.; Beyer, J.; Huetink, Han; Cesar de Sa, Jose M.A.; Santos, Abel D.

    2007-01-01

    Metastable austenitic stainless steels are designed to be thermodynamically unstable such that deformation even at room temperatures can bring about a change in the phase of face centred cubic austenite to either hexagonal close packed martensite and/or to body centred cubic martensite. This solid

  2. DETERMINATION OF METAL IONS RELEASED BY STAINLESS ...

    African Journals Online (AJOL)

    The amounts of cobalt, iron, manganese, nickel and chromium ions released from new and reused stainless steel arch bar used for maxillomandibular fixation was determined in Hank's solutions of different hydrogen and chloride ions concentrations, whole blood serum and phosphate buffered saline (PBS) in vitro, over a ...

  3. Granulate of stainless steel as compensator material

    NARCIS (Netherlands)

    J.P.C. van Santvoort (J. P C)

    1995-01-01

    textabstractCompensators produced with computer controlled milling devices usually consist of a styrofoam mould, filled with an appropriate material. We investigated granulate of stainless steel as filling material. This cheap, easy to use, clean and re-usable material can be obtained with an

  4. Stainless steel forgings for nuclear chemical plants

    International Nuclear Information System (INIS)

    1982-02-01

    This Specification covers detailed requirements for the supply of austenitic stainless steel forgings used in radioactive and corrosive areas within the Nuclear Industry. With the exception of 316S51 the materials specified are all suitable for contact with nitric acid, 316S51 being included as suitable for use in contact with sodium and other alkali metals at elevated temperatures. (author)

  5. Austenitic stainless steels for cryogenic service

    International Nuclear Information System (INIS)

    Dalder, E.N.C.; Juhas, M.C.

    1985-01-01

    Presently available information on austenitic Fe-Cr-Ni stainless steel plate, welds, and castings for service below 77 K are reviewed with the intent (1) of developing systematic relationships between mechanical properties, composition, microstructure, and processing, and (2) of assessing the adequacy of these data bases in the design, fabrication, and operation of engineering systems at 4 K

  6. CASE-HARDENING OF STAINLESS STEEL

    DEFF Research Database (Denmark)

    2004-01-01

    The invention relates to case-hardening of a stainless steel article by means of gas including carbon and/or nitrogen, whereby carbon and/or nitrogen atoms diffuse through the surface into the article. The method includes activating the surface of the article, applying a top layer on the activated...

  7. Maintained inspiratory activity during proportional assist ventilation in surfactant-depleted cats early after surfactant instillation: phrenic nerve and pulmonary stretch receptor activity

    Directory of Open Access Journals (Sweden)

    Schaller Peter

    2006-03-01

    Full Text Available Abstract Background Inspiratory activity is a prerequisite for successful application of patient triggered ventilation such as proportional assist ventilation (PAV. It has recently been reported that surfactant instillation increases the activity of slowly adapting pulmonary stretch receptors (PSRs followed by a shorter inspiratory time (Sindelar et al, J Appl Physiol, 2005 [Epub ahead of print]. Changes in lung mechanics, as observed in preterm infants with respiratory distress syndrome and after surfactant treatment, might therefore influence the inspiratory activity when applying PAV early after surfactant treatment. Objective To investigate the regulation of breathing and ventilatory response in surfactant-depleted young cats during PAV and during continuous positive airway pressure (CPAP early after surfactant instillation in relation to phrenic nerve activity (PNA and the activity of PSRs. Methods Seven anesthetized, endotracheally intubated young cats were exposed to periods of CPAP and PAV with the same end-expiratory pressure (0.2–0.5 kPa before and after lung lavage and after surfactant instillation. PAV was set to compensate for 75% of the lung elastic recoil. Results Tidal volume and respiratory rate were higher with lower PaCO2 and higher PaO2 during PAV than during CPAP both before and after surfactant instillation (p Conclusion PSR activity and the control of breathing are maintained during PAV in surfactant-depleted cats early after surfactant instillation, with a higher ventilatory response and a lower breathing effort than during CPAP.

  8. Nickel-free austenitic stainless steels for medical applications.

    Science.gov (United States)

    Yang, Ke; Ren, Yibin

    2010-02-01

    The adverse effects of nickel ions being released into the human body have prompted the development of high-nitrogen nickel-free austenitic stainless steels for medical applications. Nitrogen not only replaces nickel for austenitic structure stability but also much improves steel properties. Here we review the harmful effects associated with nickel in medical stainless steels, the advantages of nitrogen in stainless steels, and emphatically, the development of high-nitrogen nickel-free stainless steels for medical applications. By combining the benefits of stable austenitic structure, high strength and good plasticity, better corrosion and wear resistances, and superior biocompatibility compared to the currently used 316L stainless steel, the newly developed high-nitrogen nickel-free stainless steel is a reliable substitute for the conventional medical stainless steels.

  9. Serial measurement of tear meniscus by FD-OCT after instillation of artificial tears in patients with dry eyes.

    Science.gov (United States)

    Bujak, Matthew C; Yiu, Samuel; Zhang, Xinbo; Li, Yan; Huang, David

    2011-01-01

    To use Fourier-domain optical coherence tomography (FD-OCT) to study the effect of artificial tears on the tear meniscus in patients with dry eyes. The lower tear meniscus of 16 consecutive patients with dry eyes was imaged by an FD-OCT system (RTVue; Optovue, Inc., Fremont, CA). Baseline and five serial pairs of measurements were taken after the instillation of artificial tears (Optive; Allergan, Irvine, CA) at 1, 2, 5, 10, and 15 minutes. The lower meniscus height, depth, and area were measured with a computer caliper. Baseline meniscus measurements were 235.5 ± 150.0 μm, 138.1 ± 78.7 μm, and 0.020 ± 0.022 mm(2) for height, depth, and area, respectively. After instillation of artificial tears, all lower tear meniscus parameters remained significantly elevated for 5 minutes and returned to baseline by 10 minutes. FD-OCT is able to quantify a dramatic initial increase in tear meniscus, followed by a decay back to baseline values after approximately 5 minutes. FD-OCT may be useful in objectively quantifying the dynamic efficacy of dry eye treatments. Copyright 2011, SLACK Incorporated.

  10. Long-term follow-up of lung biodistribution and effect of instilled SWCNTs using multiscale imaging techniques

    International Nuclear Information System (INIS)

    Al Faraj, Achraf; Bessaad, Amine; Cieslar, Katarzyna; Canet-Soulas, Emmanuelle; Cremillieux, Yannick; Lacroix, Ghislaine

    2010-01-01

    Due to their distinctive properties, single-walled carbon nanotubes (SWCNTs) are being more and more extensively used in nanotechnology, with prospects in nanomedicine. It would therefore appear essential to develop and apply appropriate imaging tools for detecting and evaluating their biological impacts with the prospect of medical applications or in the situation of accidental occupational exposure. It has been shown recently that raw SWCNTs with metallic impurities can be noninvasively detected in the lungs by hyperpolarized 3 helium (HP- 3 He) MRI. Moreover raw and purified SWCNTs had no acute biological effect. The purpose of the present longitudinal study was to investigate long-term follow-up by imaging, as well as chronic lung effects. In a 3-month follow-up study, multiscale imaging techniques combining noninvasive HP- 3 He and proton (H) MRI to ex vivo light (histopathological analysis) and transmission electron microscopy (TEM) were used to assess the biodistribution and biological effects of intrapulmonary instilled raw SWCNTs. Specific in vivo detection of carbon nanotubes with MRI relied on their intrinsic metal impurities. MRI also has the ability to evaluate tissue inflammation by the follow-up of local changes in signal intensity. MRI and ex vivo microscopy techniques showed that granulomatous and inflammatory reactions were produced in a time and dose dependent manner by instilled raw SWCNTs.

  11. Studies of stainless steel exposed to sandblasting

    Directory of Open Access Journals (Sweden)

    Horodek Paweł

    2015-12-01

    Full Text Available The influence of sandblasting on surface and subsurface of stainless steel is investigated using variable energy positron beam (VEP, positron annihilation spectroscopy (PAS, scanning electron microscopy (SEM, and atomic force microscopy (AFM. Samples of stainless steel were blasted using 110 μm particles of Al2O3 under different pressure and time duration. In the case of sandblasting for 90 s, the reduction of positron diffusion length depending on the applied pressure was observed. Sandblasting during 30 s leads only to the reduction of positron diffusion length to about 60 nm for all samples. Positron lifetimes close to 170 ps measured using positrons emitted directly from the source point to the presence of vacancies on the dislocation lines. SEM and AFM images show that surface roughness depends rather on pressure of sandblasting than time of exposition.

  12. Plasma spot welding of ferritic stainless steels

    International Nuclear Information System (INIS)

    Lesnjak, A.; Tusek, J.

    2002-01-01

    Plasma spot wedding of ferritic stainless steels studied. The study was focused on welding parameters, plasma and shieldings and the optimum welding equipment. Plasma-spot welded overlap joints on a 0.8 mm thick ferritic stainless steel sheet were subjected to a visual examination and mechanical testing in terms of tension-shear strength. Several macro specimens were prepared Plasma spot welding is suitable to use the same gas as shielding gas and as plasma gas , i. e. a 98% Ar/2% H 2 gas mixture. Tension-shear strength of plasma-spot welded joint was compared to that of resistance sport welded joints. It was found that the resistance welded joints withstand a somewhat stronger load than the plasma welded joints due to a large weld sport diameter of the former. Strength of both types of welded joints is approximately the same. (Author) 32 refs

  13. State on AISI 304 Stainless Steel

    Directory of Open Access Journals (Sweden)

    A. Fattah-alhosseini

    2011-01-01

    Full Text Available The passivity and protective nature of the passive films are essentially related to ionic and electronic transport processes, which are controlled by the optical and electronic properties of passive films. In this study, the electrochemical behavior of passive films anodically formed on AISI 304 stainless steel in sulfuric acid solution has been examined using electrochemical impedance spectroscopy. AISI 304 in sulphuric acid solution is characterized by high interfacial impedance, thereby illustrating its high corrosion resistance. Results showed that the interfacial impedance and the polarization resistance (pol initially increase with applied potential, within the low potential passive. However, at a sufficiently high potential passive (>0.4 V, the interfacial impedance and the polarization resistance decrease with increasing potential. An electrical equivalent circuit based on the impedance analysis, which describes the behavior of the passive film on stainless steel more satisfactorily than the proposed models, is presented.

  14. Evolution of stainless steels in nuclear industry

    International Nuclear Information System (INIS)

    Tavassoli, Farhad

    2010-01-01

    Starting with the stainless steels used in the conventional industry, their adoption and successive evolutions in the nuclear industry, from one generation of nuclear reactors to another, is presented. Specific examples for several steels are given, covering fabrication procedures, qualification methods, property databases and design allowable stresses, to show how the ever-increasing demands for better performance and reliability, in particular under neutron irradiation, have been met. Particular attention is paid to the austenitic stainless steels types 304L, 316L, 316L(N), 316L(N)-IG, titanium stabilized grade 321, precipitation strengthened alloy 800, conventional and low activation ferritic/martensitic steels and their oxygen dispersion strengthening (ODS) derivatives. For each material, the evolution of the associated filler metal and welding techniques are also presented. (author)

  15. Microstructure of laser cladded martensitic stainless steel

    CSIR Research Space (South Africa)

    Van Rooyen, C

    2006-08-01

    Full Text Available of austenitic solidification. Table 4 - Chemical composition of the laser cladded martensitic stainless steel in the dendritic and interdendritic areas Material Area C* Cr Ni Mn Si Mo Dendritic 0.3 12.8 0.15 0.7 0.65 0.02 Fe211-1 (420) Off... alloy steels and are shown in Table 4. Ms (ºC) = 550 – 350C – 40Mn - 20Cr – 10Mo – 17Ni – 8W – 35V – 10Cu + 15Co + 30Al (Eq 3) Table 5 - Ms temperatures of laser cladded martensitic stainless steel Material Ms Dendritic area (ºC) Ms...

  16. Diffraction study on aging duplex stainless steel

    International Nuclear Information System (INIS)

    Ishigaki, Toru; Miura, Takayuki; Kuwano, Hisashi; Torii, Syuuki; Kamiyama, Takashi

    2001-01-01

    SUS329J2L duplex stainless steels exhibit high strength and resistance to corrosion, so widely used in piping of industrial plants. However, it is known that they are brought deterioration of strength using for long time. This reason of this deterioration is that ferrite decomposes to Fe-rich α phase and Cr-rich α' phase and, Cr-rich α' phase decreases mechanical properties and resistance for corrosion. In this experiment, we made neutron diffraction experiments on long time aging (625 K, 16000 h) duplex stainless steel to observe the behavior for α phase and α' phase, using Sirius diffractometer at KENS. The result shows, the lattice parameters in α phase were decreased. In contrast to, its in austenite (γ phase) were slightly increased. (author)

  17. 76 FR 34964 - Stainless Steel Bar From India: Partial Rescission of Antidumping Duty Administrative Review

    Science.gov (United States)

    2011-06-15

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-533-810] Stainless Steel Bar From... the antidumping duty order on stainless steel bar from India for the period of review February 1, 2010....; Outokumpu Stainless Bar, Inc.; Universal Stainless & Alloy Products, Inc.; and Valbruna Slater Stainless...

  18. Pitting corrosion resistant austenite stainless steel

    Science.gov (United States)

    van Rooyen, D.; Bandy, R.

    A pitting corrosion resistant austenite stainless steel comprises 17 to 28 wt. % chromium, 15 to 26 wt. % nickel, 5 to 8 wt. % molybdenum, and 0.3 to 0.5 wt. % nitrogen, the balance being iron, unavoidable impurities, minor additions made in the normal course of melting and casting alloys of this type, and may optionally include up to 10 wt. % of manganese, up to 5 wt. % of silicon, and up to 0.08 wt. % of carbon.

  19. Fatigue fracture modes of a stainless steel

    International Nuclear Information System (INIS)

    Pacheco, D.J.; Souza e Silva, A.S. de; Monteiro, S.N.

    1977-01-01

    The influence of strain hardening and martensite phase transformation on the fatigue fracture regions (pulsative tension) of a Stainless Steel type AISI 316 was investigated. This lead to the conclusion that the greater austenite strain hardening level only favours the occurrence of a brittle fracture. Also, in as much as the static induced martensite is concerned, a direct influence on the failure process was not observed, whereas, apparently, the one transformed under cyclic loading has no contribution to the rupture mechanisms. (author) [pt

  20. Corrosion Properties of Laser Welded Stainless Steel

    DEFF Research Database (Denmark)

    Weldingh, Jakob; Olsen, Flemmming Ove

    1997-01-01

    In this paper the corrosion properties of laser welded AISI 316L stainless steel are examined. A number of different welds has been performed to test the influence of the weld parameters of the resulting corrosion properties. It has been chosen to use the potential independent critical pitting...... temperature (CPT) test as corrosion test. The following welding parameters are varied: Welding speed, lsser power, focus point position and laser operation mode (CW or pulsed)....

  1. Ferritic stainless steels: corrosion resistance + economy

    International Nuclear Information System (INIS)

    Remus, A.L.

    1976-01-01

    Ferritic stainless steels provide corrosion resistance at lower cost. They include Type 409, Type 439, 18SR, 20-Mo (1.6 Mo), 18-2 (2 Mo), 26-1S, E-Brite 26-1, 29 Cr-4 Mo, and 29 Cr-4 Mo-2 Ni. Their corrosion and mechanical properties are examined. Resistance to stress-corrosion cracking is an advantage compared to austenitic types

  2. Impact Testing of Stainless Steel Materials

    International Nuclear Information System (INIS)

    R. K. Blandford; D. K. Morton; T. E. Rahl; S. D. Snow

    2005-01-01

    Stainless steels are used for the construction of numerous spent nuclear fuel or radioactive material containers that may be subjected to high strains and moderate strain rates (10 to 200 per second) during accidental drop events. Mechanical characteristics of these materials under dynamic (impact) loads in the strain rate range of concern are not well documented. The goal of the work presented in this paper was to improve understanding of moderate strain rate phenomena on these materials. Utilizing a drop-weight impact test machine and relatively large test specimens (1/2-inch thick), initial test efforts focused on the tensile behavior of specific stainless steel materials during impact loading. Impact tests of 304L and 316L stainless steel test specimens at two different strain rates, 25 per second (304L and 316L material) and 50 per second (304L material) were performed for comparison to their quasi-static tensile test properties. Elevated strain rate stress-strain curves for the two materials were determined using the impact test machine and a ''total impact energy'' approach. This approach considered the deformation energy required to strain the specimens at a given strain rate. The material data developed was then utilized in analytical simulations to validate the final elevated stress-strain curves. The procedures used during testing and the results obtained are described in this paper

  3. Colorimetric values of esthetic stainless steel crowns.

    Science.gov (United States)

    Hosoya, Yumiko; Omachi, Koichi; Staninec, Michal

    2002-01-01

    The colorimetric values of two different kinds of esthetic stainless steel crowns were measured and compared with the colorimetric values of primary anterior teeth in Japanese children. The colorimetric values of resin composite-faced stainless steel crowns (Kinder Krown) and epoxy-coated stainless steel crowns (White Steel Crown) were measured with a color difference meter. The Commission Internationale de Eclairage L*, a*, b*, and delta E*ab values and Munsell value, chroma, and hue were calculated. The data were compared with previously reported colorimetric values of Japanese primary anterior teeth measured with the same color difference meter used in this study. Compared to Japanese primary anterior teeth, Kinder Krown Pedo I and Pedo II showed much higher L* values and lower hue; on the other hand, White Steel Crown showed much higher L*, a*, b* values, much higher value and chroma, and much lower hue. Color analysis revealed that the colors of the White Steel Crown and Kinder Krown Pedo I were substantially different from the color of Japanese primary anterior teeth. The color difference between Pedo II crowns and Japanese primary anterior teeth was relatively high, but the color of Pedo II might be acceptable for clinical use.

  4. Computer simulation of sensitization in stainless steels

    Energy Technology Data Exchange (ETDEWEB)

    Logan, R W

    1983-12-20

    Stainless steel containers are prime candidates for the containment of nuclear waste in tuff rock. The thermal history of a container involves exposure to temperatures of 500 to 600/sup 0/C when it is welded and possibly filled with molten waste glass, followed by hundreds of years exposure in the 100 to 300/sup 0/C range. The problems of short- and long-term sensitization in stainless steels have been addressed by two computer programs. The TTS program uses classical nucleation and growth theory plus experimental input to predict the onset of precipitation or sensitization under complex thermal histories. The FEMGB program uses quadratic finite-element methods to analyze diffusion processes and chromium depletion during precipitate growth. The results of studies using both programs indicate that sensitization should not be a problem in any of the austenitic stainless steels considered. However, more precise information on the process thermal cycles, especially during welding of the container, is needed. Contributions from dislocation pipe diffusion could promote long-term low-temperature sensitization.

  5. Impact of hydrochloric acid instillation on salvage of infected central venous catheters in children with acute lymphoblastic leukaemia.

    Science.gov (United States)

    Madsen, Mette; Rosthøj, Steen

    2013-01-01

    Bacteraemia associated with indwelling central venous catheters (CVC) causes significant morbidity in children with cancer. Hydrochloric acid (HCl) instillations have been reported to salvage CVCs with antibiotic-refractory infection. We implemented this treatment in 2002. The impact on the survival of CVCs has been evaluated in a retrospective cohort study of children with acute lymphoblastic leukaemia (ALL). Children with newly diagnosed ALL during 1999-2005 having their first CVC inserted before (n = 16) and after (n = 24) the introduction of the procedure were studied. All bacteraemic episodes were reviewed, recording bacteriological findings and treatment, and the time to premature or planned removal of the CVC was determined. In the comparison cohort, 31.0% (9/29) of bacteraemic episodes led to removal of the CVC, compared to 5.5% (2/36) in the intervention cohort (p = 0.01). Thus, the rate of catheter loss due to infection fell from 56.3% (9/16) to 8.3% (2/24) after introducing HCl treatment (p = 0.0025). Overall, the premature catheter removal rate fell from 75.0% (12/16) to 45.8% (11/24) (p = 0.10). Analysed in a CUSUM plot the reduced frequency of premature CVC removal evidently coincided with the introduction of the procedure. In a subgroup analysis of 21 monobacterial infections with coagulase-negative staphylococci, a decrease in systemic and lock antibiotic therapy was found. No adverse events were noted. HCl instillations significantly reduced the need to remove and replace CVCs. The procedure is practical, appears to be safe, and may reduce the consumption of antibiotics.

  6. Characterization of thermal aging of duplex stainless steel by SQUID

    International Nuclear Information System (INIS)

    Isobe, Y.; Kamimura, A.; Aoki, K.; Nakayasu, F.

    1995-01-01

    Thermal aging is a growing concern for long-term-aged duplex stainless steel piping in nuclear power plants. Superconducting QUantum Interference Device (SQUID) was used for the detection of thermal aging of SUS329 rolled duplex stainless steel and SCS16 cast duplex stainless steel. It was found that the SQUID output signal pattern in the presence of AC magnetic field applied to the specimen was sensitive to the changes in electromagnetic properties due to thermal aging

  7. Tritium distributing in stainless steel determined by chemical etchin

    International Nuclear Information System (INIS)

    Xiong Yifu; Luo Deli; Chen Changan; Chen Shicun; Jing Wenyong

    2009-01-01

    The depth distribution of tritium in stainless steel was measured by chemical etching. The results show that the method can more quantitatively evaluate the tritium distributing in stainless steel. The maximum amount of tritium which distributed in crystal lattice of stainless steel is limitted by its solubility at room temperature. The other form of tritium in stainless steel is gaseous tritium that are trapped by defects, impurities, fractures, etc. within it. The gaseous tritium is several times more than the solid-dissolved tritium. (authors)

  8. Stainless Steel Leaches Nickel and Chromium into Foods During Cooking

    Science.gov (United States)

    Kamerud, Kristin L.; Hobbie, Kevin A.; Anderson, Kim A.

    2014-01-01

    Toxicological studies show that oral doses of nickel and chromium can cause cutaneous adverse reactions such as dermatitis. Additional dietary sources, such as leaching from stainless steel cookware during food preparation, are not well characterized. This study examined stainless steel grades, cooking time, repetitive cooking cycles, and multiple types of tomato sauces for their effects on nickel and chromium leaching. Trials included three types of stainless steels and a stainless steel saucepan; cooking times of 2 to 20 hours, ten consecutive cooking cycles, and four commercial tomato sauces. After a simulated cooking process, samples were analyzed by ICP-MS for Ni and Cr. After six hours of cooking, Ni and Cr concentrations in tomato sauce increased up to 26- and 7-fold respectively, depending on the grade of stainless steel. Longer cooking durations resulted in additional increases in metal leaching, where Ni concentrations increased 34 fold and Cr increased approximately 35 fold from sauces cooked without stainless steel. Cooking with new stainless steel resulted in the largest increases. Metal leaching decreases with sequential cooking cycles and stabilized after the sixth cooking cycle, though significant metal contributions to foods were still observed. The tenth cooking cycle, resulted in an average of 88 μg of Ni and 86 μg of Cr leached per 126 g serving of tomato sauce. Stainless steel cookware can be an overlooked source of nickel and chromium, where the contribution is dependent on stainless steel grade, cooking time, and cookware usage. PMID:23984718

  9. Colleges Urged to Instill "Charitable Impulse" in Students, Inspire Them to Reorient Public Policy as Well as Donate Their Time and Money.

    Science.gov (United States)

    McMillen, Liz

    1987-01-01

    The president of the Council on Foundations, James A. Joseph, urges educators to develop volunteers who can eliminate the causes of social problems. Colleges and universities are in a special position to instill a sense of social responsibility in students. (MLW)

  10. Stainless steel reinforcement as a replacement for epoxy coated steel in bridge decks : final report.

    Science.gov (United States)

    2013-08-01

    The corrosion resistance of 2304 stainless steel reinforcement and stainless steel clad reinforcement was compared to conventional and epoxy-coated reinforcement (ECR). 2304 stainless steel was tested in both the as-received condition (dark mottled f...

  11. Low temperature surface hardening of stainless steel; the role of plastic deformation

    DEFF Research Database (Denmark)

    Bottoli, Federico; Jespersen, Freja Nygaard; Hattel, Jesper Henri

    2016-01-01

    Thermochemical surface engineering by nitriding of austenitic stainless steel transforms the surface zone into expanded austenite, which improves the wear resistance of the stainless steel while preserving the stainless behavior. As a consequence of the thermochemical surface engineering, huge re...

  12. Investigating the Crevice Corrosion Behavior of Coated Stainless Steel in Seawater

    National Research Council Canada - National Science Library

    Kain, Robert

    2000-01-01

    .... austenitic stainless steel. Testing in natural seawater has demonstrated that coatings can protect susceptible stainless steel from barnacle related crevice corrosion and localized corrosion at weldments...

  13. Antimicrobial Cu-bearing stainless steel scaffolds

    International Nuclear Information System (INIS)

    Wang, Qiang; Ren, Ling; Li, Xiaopeng; Zhang, Shuyuan; Sercombe, Timothy B.; Yang, Ke

    2016-01-01

    Copper-bearing stainless steel scaffolds with two different structures (Body Centered Cubic and Gyroid labyrinth) at two solid fractions (25% and 40%) were fabricated from both 316L powder and a mixture of 316L and elemental Cu powder using selective laser melting, and relative 316L scaffolds were served as control group. After processing, the antimicrobial testing demonstrated that the 316L-Cu scaffolds presented excellent antimicrobial activity against Escherichia coli and Staphylococcus aureus, and the cell viability assay indicated that there was no cytotoxic effect of 316L-Cu scaffolds on rat marrow mesenchymal stem cells. As such, these have the potential to reduce implant-associated infections. The Cu was also found to homogeneously distribute within the microstructure by scanning electronic microcopy. The addition of Cu would not significantly affect its strength and stiffness compared to 316L scaffold, and the stiffness of all the scaffolds (3-20GPa) is similar to that of bone and much less than that of bulk stainless steel. Consequently, fabrication of such low stiffness porous structures, especially coupled with the addition of antimicrobial Cu, may provide a new direction for medical stainless steels. - Highlights: • 316L-Cu scaffolds were fabricated by using selective laser melting (SLM). • 316L-Cu scaffolds showed satisfied antimicrobial activities. • 316L-Cu scaffolds have no cytotoxic effect on normal cells. • Other properties of 316L-Cu scaffolds were similar to 316L scaffolds. • 316L-Cu scaffolds have the potential to be used in orthopedic applications.

  14. Aging degradation of cast stainless steel

    International Nuclear Information System (INIS)

    Chopra, O.K.; Chung, H.M.

    1986-10-01

    A program is being conducted to investigate the significance of in-service embrittlement of cast duplex stainless steels under light-water reactor operating conditions. Microstructures of cast materials subjected to long-term aging either in reactor service or in the laboratory have been characterized by TEM, SANS, and APFIM techniques. Two precipitate phases, i.e., the Cr-rich α' and Ni- and Si-rich G phase, have been identified in the ferrite matrix of the aged steels. The results indicate that the low-temperature embrittlement is primarily caused by α' precipitates which form by spinodal decomposition. The relative contribution of G phase to loss of toughness is now known. Microstructural data also indicate that weakening of ferrite/austenite phase boundary by carbide precipitates has a significant effect on the onset and extent of embrittlement of the high-carbon CF-8 and CF-8M grades of stainless steels, particularly after aging at 400 or 450 0 C. Data from Charpy-impact, tensile, and J-R curve tests for several heats of cast stainless steel aged up to 10,000 h at 350, 400, and 450 0 C are presented and correlated with the microstructural results. Thermal aging of the steels results in an increase in tensile strength and a decrease in impact energy, J/sub IC/, and tearing modulus. The fracture toughness results show good agreement with the Charpy-impact data. The effects of compositional and metallurgical variables on loss of toughness are discussed

  15. Diamond deposition on siliconized stainless steel

    International Nuclear Information System (INIS)

    Alvarez, F.; Reinoso, M.; Huck, H.; Rosenbusch, M.

    2010-01-01

    Silicon diffusion layers in AISI 304 and AISI 316 type stainless steels were investigated as an alternative to surface barrier coatings for diamond film growth. Uniform 2 μm thick silicon rich interlayers were obtained by coating the surface of the steels with silicon and performing diffusion treatments at 800 deg. C. Adherent diamond films with low sp 2 carbon content were deposited on the diffused silicon layers by a modified hot filament assisted chemical vapor deposition (HFCVD) method. Characterization of as-siliconized layers and diamond coatings was performed by energy dispersive X-ray analysis, scanning electron microscopy, X-ray diffraction and Raman spectroscopy.

  16. STRUCTURAL STRESS RELAXATION IN STAINLESS INSTABILITY STEEL

    Directory of Open Access Journals (Sweden)

    S. Lyabuk

    2017-06-01

    Full Text Available The approach to the description of conditions of martensitic transformation in austenitic steel is advanced. Transformation induced hardening is the result of Le Chatelier principle in instability alloys. The phase transformation in austenitic instability stainless steel is the cause of reduction of grain refining and increase of strength. It was experimentally shown that physical-mechanical characteristics of the prepared materials were defined by the structure and inhomogeneous distribution of the hardening phase within a grain. The reasons for high thermal stability of inverse austenitic were established. The factors determining the inverse austenitic relaxation resistibility and resources for its increasing were revealed.

  17. Static strain aging in austenitic stainless steels

    International Nuclear Information System (INIS)

    Monteiro, S.N.

    1978-07-01

    The static strain aging effects were investigated in austenitic stainless steels by measuring the yield points developed in tensile tests following the arrest of the crosshead for some period of time. The results appear to indicate that the dragging of dislocations in the interval of temperatures from 100 to 300 0 C, where the strain aging is effective, does not apparently depend on the Cottrell's atmosphere. Moreover the influence of the pre-deformation and time on the yield point intensity displayed the existence of stages. The strain aging mechanics and the reasons for the stages were discussed. (Author) [pt

  18. Effects of intratracheal administration of nuclear factor-kappaB decoy oligodeoxynucleotides on long-term cigarette smoke-induced lung inflammation and pathology in mice

    Directory of Open Access Journals (Sweden)

    Wang Yu-Zhu

    2009-08-01

    Full Text Available Abstract To determine if nuclear factor-κB (NF-κB activation may be a key factor in lung inflammation and respiratory dysfunction, we investigated whether NF-κB can be blocked by intratracheal administration of NF-κB decoy oligodeoxynucleotides (ODNs, and whether decoy ODN-mediated NF-κB inhibition can prevent smoke-induced lung inflammation, respiratory dysfunction, and improve pathological alteration in the small airways and lung parenchyma in the long-term smoke-induced mouse model system. We also detected changes in transcriptional factors. In vivo, the transfection efficiency of NF-κB decoy ODNs to alveolar macrophages in BALF was measured by fluorescein isothiocyanate (FITC-labeled NF-κB decoy ODNs and flow cytometry post intratracheal ODN administration. Pulmonary function was measured by pressure sensors, and pathological changes were assessed using histology and the pathological Mias software. NF-κB and activator protein 1(AP-1 activity was detected by the electrophoretic motility shift assay (EMSA. Mouse cytokine and chemokine pulmonary expression profiles were investigated by enzyme-linked immunosorbent assay (ELISA in bronchoalveolar lavage fluid (BALF and lung tissue homogenates, respectively, after repeated exposure to cigarette smoke. After 24 h, the percentage of transfected alveolar macrophages was 30.00 ± 3.30%. Analysis of respiratory function indicated that transfection of NF-κB decoy ODNs significantly impacted peak expiratory flow (PEF, and bronchoalveolar lavage cytology displayed evidence of decreased macrophage infiltration in airways compared to normal saline-treated or scramble NF-κB decoy ODNs smoke exposed mice. NF-κB decoy ODNs inhibited significantly level of macrophage inflammatory protein (MIP 1α and monocyte chemoattractant protein 1(MCP-1 in lung homogenates compared to normal saline-treated smoke exposed mice. In contrast, these NF-κB decoy ODNs-treated mice showed significant increase in the

  19. Effects of intratracheal administration of nuclear factor-kappaB decoy oligodeoxynucleotides on long-term cigarette smoke-induced lung inflammation and pathology in mice.

    Science.gov (United States)

    Li, Yu-Tao; He, Bei; Wang, Yu-Zhu; Wang, Jing

    2009-08-25

    To determine if nuclear factor-kappaB (NF-kappaB) activation may be a key factor in lung inflammation and respiratory dysfunction, we investigated whether NF-kappaB can be blocked by intratracheal administration of NF-kappaB decoy oligodeoxynucleotides (ODNs), and whether decoy ODN-mediated NF-kappaB inhibition can prevent smoke-induced lung inflammation, respiratory dysfunction, and improve pathological alteration in the small airways and lung parenchyma in the long-term smoke-induced mouse model system. We also detected changes in transcriptional factors. In vivo, the transfection efficiency of NF-kappaB decoy ODNs to alveolar macrophages in BALF was measured by fluorescein isothiocyanate (FITC)-labeled NF-kappaB decoy ODNs and flow cytometry post intratracheal ODN administration. Pulmonary function was measured by pressure sensors, and pathological changes were assessed using histology and the pathological Mias software. NF-kappaB and activator protein 1(AP-1) activity was detected by the electrophoretic motility shift assay (EMSA). Mouse cytokine and chemokine pulmonary expression profiles were investigated by enzyme-linked immunosorbent assay (ELISA) in bronchoalveolar lavage fluid (BALF) and lung tissue homogenates, respectively, after repeated exposure to cigarette smoke. After 24 h, the percentage of transfected alveolar macrophages was 30.00 +/- 3.30%. Analysis of respiratory function indicated that transfection of NF-kappaB decoy ODNs significantly impacted peak expiratory flow (PEF), and bronchoalveolar lavage cytology displayed evidence of decreased macrophage infiltration in airways compared to normal saline-treated or scramble NF-kappaB decoy ODNs smoke exposed mice. NF-kappaB decoy ODNs inhibited significantly level of macrophage inflammatory protein (MIP) 1alpha and monocyte chemoattractant protein 1(MCP-1) in lung homogenates compared to normal saline-treated smoke exposed mice. In contrast, these NF-kappaB decoy ODNs-treated mice showed

  20. 77 FR 23752 - Drawn Stainless Steel Sinks From China

    Science.gov (United States)

    2012-04-20

    ... COMMISSION Drawn Stainless Steel Sinks From China Determinations On the basis of the record \\1\\ developed in... reason of imports from China of drawn stainless sinks, provided for in subheading 7324.10.00 of the... than fair value (LTFV) and subsidized by the Government of China. \\1\\ The record is defined in sec. 207...

  1. Solidification cracking in austenitic stainless steel welds

    Indian Academy of Sciences (India)

    Solidification cracking is a significant problem during the welding of austenitic stainless steels, particularly in fully austenitic and stabilized compositions. Hot cracking in stainless steel welds is caused by low-melting eutectics containing impurities such as S, P and alloy elements such as Ti, Nb. The WRC-92 diagram can be ...

  2. Stress corrosion cracking of AISI 321 stainless steel in acidic ...

    Indian Academy of Sciences (India)

    Unknown

    The stress corrosion cracking (SCC) of AISI 321 stainless steel in acidic chloride solution was studied by slow strain rate (SSR) ... Stress corrosion cracking; chloride; stainless steel; inhibitor. 1. Introduction. Stress corrosion cracking (SCC) ..... Xi'an Jiaotong University Press) (in Chinese). Huang Y L, Cao C N, Lu M and Lin ...

  3. Analysis of polypyrrole-coated stainless steel electrodes-Estimation ...

    Indian Academy of Sciences (India)

    Analysis of polypyrrole-coated stainless steel electrodes - Estimation of specific capacitances and construction of equivalent circuits. R Ramya M V Sangaranarayanan ... The galvanostatic polymerization of pyrrole is carried out on stainless steel electrodes using -toluene sulphonic acid. The morphology of the film is ...

  4. Estimation of embrittlement during aging of AISI 316 stainless steel ...

    Indian Academy of Sciences (India)

    Unknown

    Nitrogen additions to stainless steels have been found beneficial as it improves austenite stability and thereby ... selected keeping in mind the service conditions in the nuclear reactors where these steels are used. .... increases. δ-Ferrite in austenitic stainless steel weld met- als containing FN4–FN11 decomposes to α + α′ ...

  5. Withdrawal Strength and Bending Yield Strength of Stainless Steel Nails

    Science.gov (United States)

    Douglas R. Rammer; Samuel L. Zelinka

    2015-01-01

    It has been well established that stainless steel nails have superior corrosion performance compared to carbon steel or galvanized nails in treated wood; however, their mechanical fastening behavior is unknown. In this paper, the performance of stainless steel nails is examined with respect to two important properties used in wood connection design: withdrawal strength...

  6. Stainless steels for seawater desalination plants; Nichtrostende Staehle fuer Meerwasserentsalzungsanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Uhlig, G. [ThyssenKrupp Nirosta GmbH, Krefeld (Germany)

    2007-07-01

    Seawater desalination plants can be used to produce drinking water with low chloride concentrations. Stainless steels are an elementary component of the various process technologies in such plants. Due to growing demand for drinking water - especially in the Arabian states, but also in southern Europe - seawater desalination plants represent a very interesting area of application with increasing economic importance for stainless steels. (orig.)

  7. Reliability and performance evaluation of stainless and mild steel ...

    African Journals Online (AJOL)

    Reliability and performance of stainless and mild steel products in methanolic and aqueous sodium chloride media have been investigated. Weight-loss and pre-exposure methods were used. There was a higher rate of weight-loss of mild steels and stainless steels in 1% HCl methanolic solution than in aqueous NaCl ...

  8. Rapport du congrès EUROCALL 2000 et du symposium InSTIL 2000 (Dundee, Ecosse

    Directory of Open Access Journals (Sweden)

    Pierre Machu

    2000-12-01

    Full Text Available Le congrès annuel de EUROCALL (2000 (European Association for Computer Assisted Language Learning s'est déroulé du 31 août au 2 septembre 2000 à l'Université d'Abertay-Dundee et avait pour thème : Innovations dans l'apprentissage des langues au troisième millénaire - Réseaux pour la formation continue, interdisciplinarité et réponse intelligente de la machine (voir le site EUROCALL 2000 (2000. Environ 230 délégués provenant de 30 pays se sont rassemblés à Dundee. Les séances plénières et les communications (présentation de recherches ou démonstrations s'articulaient par conséquent autour de sous-thèmes tels que recherche en acquisition d'une langue seconde et ALAO, exploitation ou conception de matériaux pour la toile, communication médiatisée par ordinateur, centres de langues et apprentissage des langues de spécialité, traitement du language naturel et technologie de la parole. La technologie de la parole était également au coeur des préoccupations et travaux des 80 participants au symposium d'InSTIL 2000 (2000 (Intégration des technologies de la parole dans l'apprentissage des langues qui s'est déroulé durant les deux jours précédant le congrès EUROCALL 2000. InSTIL 2000 était organisé par le groupe d'intérêts spéciaux (GIS InSTIL (2000, (Integrating Speech Technology in Language Learning issu des trois associations CALICO (2000 (Computer Assisted Language Instruction Consortium, EUROCALL (2000 et ISCA (2000 (International Speech Communication Association.

  9. Citric Acid Passivation of Stainless Steel

    Science.gov (United States)

    Yasensky, David; Reali, John; Larson, Chris; Carl, Chad

    2009-01-01

    Passivation is a process for cleaning and providing corrosion protection for stainless steel. Currently, on Kennedy Space Center (KSC), only parts passivated with nitric acid are acceptable for use. KSC disposes of approximately 125gal of concentrated nitric acid per year, and receives many parts from vendors who must also dispose of used nitric acid. Unfortunately, nitric acid presents health and environmental hazards. As a result, several recent industry studies have examined citric acid as an alternative. Implementing a citric acid-based passivation procedure would improve the health and environmental safety aspects of passivation process. However although there is a lack of published studies that conclusively prove citric acid is a technically sound passivation agent. In 2007, NASA's KSC Materials Advisory Working Group requested the evaluation of citric acid in place of nitric acid for passivation of parts at KSC. United Space Alliance Materials & Processes engineers have developed a three-phase test plan to evaluate citric acid as an alternative to nitric acid on three stainless steels commonly used at KSC: UNS S30400, S41000, and S17400. Phases 1 and 2 will produce an optimized citric acid treatment based on results from atmospheric exposure at NASA's Beach Corrosion Facility. Phase 3 will compare the optimized solution(s) with nitric acid treatments. If the results indicate that citric acid passivates as well or better than nitric acid, NASA intends to approve this method for parts used at the Kennedy Space Center.

  10. Carburization of stainless steel furnace tubes

    Energy Technology Data Exchange (ETDEWEB)

    Mirabal, E.; Molina, C. [Refineria Isla, Curazao, S.A., P.O. Box 3843. Curacao, (Netherlands Antilles); Hau, J.L.; Mayorga, A.G. [PDVSA-Intevep. P.O. Box 76343. Caracas 1070A, Venezuela (Venezuela)

    1998-12-31

    Stainless steel containing molybdenum are usually recommended to resist naphtenic acid corrosion in vacuum heaters. In 1993 the original 5Cr-1/2Mo roof tubes of the furnace in a vacuum unit were replaced by stainless steel 316 Ti to minimize tube replacement and increase heater reliability. Unexpectedly, some of the new tubes failed after only three years of service and just one year after undergoing the last inspection. The damage occurred in the form of deep holes and perforations, starting from the outside tube surface on the fireside. Coke build-up occurred due to severe operating conditions, overheating the tubes on the fireside, above 675 Centigrade. Metallographic and Scanning Electron Microscopy (Sem) examination revealed internal and external carburization of the material due to the presence of coke and combustion ashes, respectively. The increase in the skin metal temperature facilitated the diffusion of carbon from these carbon-rich deposits into the low carbon content material (0.023%). Depletion of chromium at the grain boundaries due to the massive formation of chromium carbides, resulted in a severe intergranular corrosion attack by molten salts rich in vanadium and sulfur produced by asphalt burning. Normal operating practice demands the use of steam for the heater tubes to control coke build-up. This practice had been first reduced and then eliminated, during the past two years prior to the failure, because of economic incentives. This paper describes the root cause analysis conducted to account for these premature tube failures. (Author)

  11. Carburization of stainless steel furnace tubes

    International Nuclear Information System (INIS)

    Mirabal, E.; Molina, C.; Hau, J.L.; Mayorga, A.G.

    1998-01-01

    Stainless steel containing molybdenum are usually recommended to resist naphtenic acid corrosion in vacuum heaters. In 1993 the original 5Cr-1/2Mo roof tubes of the furnace in a vacuum unit were replaced by stainless steel 316 Ti to minimize tube replacement and increase heater reliability. Unexpectedly, some of the new tubes failed after only three years of service and just one year after undergoing the last inspection. The damage occurred in the form of deep holes and perforations, starting from the outside tube surface on the fireside. Coke build-up occurred due to severe operating conditions, overheating the tubes on the fireside, above 675 Centigrade. Metallographic and Scanning Electron Microscopy (Sem) examination revealed internal and external carburization of the material due to the presence of coke and combustion ashes, respectively. The increase in the skin metal temperature facilitated the diffusion of carbon from these carbon-rich deposits into the low carbon content material (0.023%). Depletion of chromium at the grain boundaries due to the massive formation of chromium carbides, resulted in a severe intergranular corrosion attack by molten salts rich in vanadium and sulfur produced by asphalt burning. Normal operating practice demands the use of steam for the heater tubes to control coke build-up. This practice had been first reduced and then eliminated, during the past two years prior to the failure, because of economic incentives. This paper describes the root cause analysis conducted to account for these premature tube failures. (Author)

  12. Single pit propagation on austenitic stainless steel

    International Nuclear Information System (INIS)

    Heurtault, Stephane

    2016-01-01

    The electrochemical characterization of metastable events such as pitting corrosion of stainless steel in chloride electrolyte remains complex because many individual processes may occur simultaneously on the alloy surface. To overcome these difficulties, an experimental setup, the flow micro-device, has been developed to achieve the initiation of a single pit and to propagate the single pit in three dimensions. In this work, we take advantage of such a device in order to revisit the pitting process on a 316L stainless steel in a chloride - sulphate bulk. In a first step, the time evolution of the pit geometry (depth, radius) and the chemical evolution of the pit solution investigated using in situ Raman spectroscopy have shown that the pit depth propagation depends on the formation of a metal chloride and sulphate gel in the pit solution, and is controlled by the metallic cations diffusion from the pit bottom to the pit mouth. The pit radius growth is defined by the initial surface de-passivation, by the presence of a pit cover and by the gel development in the solution. all of these phenomena are function of applied potential and chemical composition of the solution. In a last step, it was demonstrated that a critical chloride concentration is needed in order to maintain the pit propagation. This critical concentration slightly increases with the pit depth. From statistical analysis performed on identical experiments, a zone diagram showing the pit stability as a function of the chloride concentration and the pit dimensions was built. (author) [fr

  13. Ion nitriding in 316=L stainless steel

    International Nuclear Information System (INIS)

    Rojas-Calderon, E.L.

    1989-01-01

    Ion nitriding is a glow discharge process that is used to induce surface modification in metals. It has been applied to 316-L austenitic stainless steel looking for similar benefits already obtained in other steels. An austenitic stainless steel was selected because is not hardenable by heat treatment and is not easy to nitride by gas nitriding. The samples were plastically deformed to 10, 20, 40, 50 AND 70% of their original thickness in order to obtain bulk hardening and to observe nitrogen penetration dependence on it. The results were: an increase of one to two rockwell hardness number (except in 70% deformed sample because of its thickness); an increase of even several hundreds per cent in microhardness knoop number in nitrided surface. The later surely modifies waste resistance which would be worth to quantify in further studies. Microhardness measured in an internal transversal face to nitrided surface had a gradual diminish in its value with depth. Auger microanalysis showed a higher relative concentration rate C N /C F e near the surface giving evidence of nitrogen presence till 250 microns deep. The color metallography etchant used, produced faster corrosion in nitrited regions. Therefore, corrosion studies have to be done before using ion nitrited 316-L under these chemicals. (Author)

  14. Antitumor activity of intratracheal inhalation of temozolomide (TMZ) loaded into gold nanoparticles and/or liposomes against urethane-induced lung cancer in BALB/c mice.

    Science.gov (United States)

    Hamzawy, Mohamed A; Abo-Youssef, Amira M; Salem, Heba F; Mohammed, Sameh A

    2017-11-01

    The current study aimed to develop gold nanoparticles (GNPs) and liposome-embedded gold nanoparticles (LGNPs) as drug carriers for temozolomide (TMZ) and investigate the possible therapeutic effects of intratracheal inhalation of nanoformulation of TMZ-loaded gold nanoparticles (TGNPs) and liposome-embedded TGNPs (LTGNPs) against urethane-induced lung cancer in BALB/c mice. Physicochemical characters and zeta potential studies for gold nanoparticles (GNPs) and liposome-embedded gold nanoparticles (LGNPs) were performed. The current study was conducted by inducing lung cancer chemically via repeated exposure to urethane in BALB/C mice. GNPs and LGNPs were exhibited in uniform spherical shape with adequate dispersion stability. GNPs and LGNPs showed no significant changes in comparison to control group with high safety profile, while TGNPs and LTGNPs succeed to improve all biochemical data and histological patterns. GNPs and LGNPs are promising drug carriers and succeeded in the delivery of small and efficient dose of temozolomide in treatment lung cancer. Antitumor activity was pronounced in animal-treated LTGNPs, these effects may be due to synergistic effects resulted from combination of temozolomide and gold nanoparticles and liposomes that may improve the drug distribution and penetration.

  15. Characterization of friction stir welded joint of low nickel austenitic stainless steel and modified ferritic stainless steel

    Science.gov (United States)

    Mondal, Mounarik; Das, Hrishikesh; Ahn, Eun Yeong; Hong, Sung Tae; Kim, Moon-Jo; Han, Heung Nam; Pal, Tapan Kumar

    2017-09-01

    Friction stir welding (FSW) of dissimilar stainless steels, low nickel austenitic stainless steel and 409M ferritic stainless steel, is experimentally investigated. Process responses during FSW and the microstructures of the resultant dissimilar joints are evaluated. Material flow in the stir zone is investigated in detail by elemental mapping. Elemental mapping of the dissimilar joints clearly indicates that the material flow pattern during FSW depends on the process parameter combination. Dynamic recrystallization and recovery are also observed in the dissimilar joints. Among the two different stainless steels selected in the present study, the ferritic stainless steels shows more severe dynamic recrystallization, resulting in a very fine microstructure, probably due to the higher stacking fault energy.

  16. Comparison of frictional resistance between conventional stainless steel, metal insert ceramic, self ligating stainless steel and self ligating ceramic with stainless steel wire : invitro study

    Directory of Open Access Journals (Sweden)

    Sivaram Subbiah

    2010-01-01

    Full Text Available Friction is an integral part of fixed orthodontic treatment. Several innovations have been made to reduce friction and thereby get predictable and faster tooth movements. Self ligating brackets are one such innovation which is said to offer the possibility of a significant reduction in average treatment times and also in anchorage requirements. Ceramic Self ligating brackets introduce recently have the added advantage of aesthetics. This study was conducted to compare the frictional resistance of conventional stainless steel, metal insert ceramic, Self ligating stainless steel and Self ligating ceramic brackets against a common stainless steel wire. Fifteen premolar in each group (0.022 Roth prescription were tested against 0.019x0.025 stainless steel wire using Lloyd universal testing machine. The conventional stainless steel brackets showed a frictional resistance of 66.47±7.86g metal insert ceramic brackets showed a frictional resistance of 77.52± 8.59g . the Self ligating stainless steel brackets had a frictional resistance of 40.21±7.76g Self ligating ceramic brackets had a frictional resistance of 72.67±5.76 g Self ligating ceramic brackets do have slightly lesser friction than metal insert ceramic brackets but significantly more than metal brackets .

  17. Intermittent negative pressure wound therapy with instillation for the treatment of persistent periprosthetic hip infections: a report of two cases

    Directory of Open Access Journals (Sweden)

    Söylemez MS

    2016-02-01

    Full Text Available Mehmet Salih Söylemez,1 Korhan Özkan,2 Bülent Kılıç,3 Samet Erinç41Department of Orthopaedics and Traumatology, Bingöl State Hospital, Bingöl, 2Department of Orthopaedics and Traumatology, Faculty of Medicine, Medeniyet University, Istanbul, 3Department of Orthopaedics and Traumatology, Orthopaedic Surgery Clinic, Istanbul Gelişim University, Tekirdağ, 4Department of Orthopaedics and Traumatology, Istanbul Medeniyet University, Göztepe Training and Research Hospital, Istanbul, TurkeyAbstract: Intermittent negative pressure wound therapy with instillation (NPWTi is starting to be used successfully to treat early periprosthetic infections of endoprostheses. However, few articles have reported the outcome of treatment with intermittent NPWTi for late persistent periprosthetic infections of the hip. In this study, we report two cases who underwent several rounds of radical wound debridement for the treatment of a late persistent periprosthetic infection of the hip. Intermittent NPWTi was used in both cases. Patients were treated successfully and there was no recurrence after 3 and 1 years of follow-up, respectively.Keywords: negative pressure, vacuum-assisted, periprosthetic infection, hip

  18. Macau, world capital for gambling: A longitudinal study of a youth program designed to instill positive values

    Directory of Open Access Journals (Sweden)

    Andrew Leung Luk

    2013-11-01

    Full Text Available Macau, world capital for gambling: A longitudinal study of a youth program designed to instil positive valuesABSTRACTThis study investigated the effectiveness of a positive youth development program for Chinese Secondary 3 students in two schools, who had been followed up since their entry to Secondary 1. A mixed research method was carried out using a pre- and post-test pre-experimental design and a focus group for the participants. The subjective outcome evaluations included participants’ perceptions of the program, program instructors, benefits of the program and overall satisfaction, and were positive. The longitudinal data from the objective outcome evaluation showed some notable improvements, and the overall effect of the program was also found to be positive for newcomers in the junior secondary years. The focus group interviews revealed mostly positive feedback in terms of the students’ general impressions of the program, with the majority of participants perceiving benefits to themselves from the program. The findings offer positive evidence of the effectiveness of the program. KEYWORDS: adolescents, positive youth development, objective outcome evaluation, subjective outcome evaluation

  19. Systematic Review and Meta-Analysis of Intravesical Hyaluronic Acid and Hyaluronic Acid/Chondroitin Sulfate Instillation for Interstitial Cystitis/Painful Bladder Syndrome

    OpenAIRE

    Jung-Soo Pyo; Won Jin Cho

    2016-01-01

    Background/Aims: To assess the efficacy of intravesical hyaluronic acid (HA) and HA/chondroitin sulfate (CS) instillation in patients with interstitial cystitis/painful bladder syndrome by systematic review and meta-analysis. Methods: A systematic literature search was performed using the keywords: ‘interstitial cystitis' or ‘painful bladder syndrome' or ‘bladder pain syndrome' and ‘hyaluronic acid', up to March 31, 2016. The primary outcome was visual analogue scale related pain symptom (VAS...

  20. The effect of wound instillation of a novel purified capsaicin formulation on postherniotomy pain: A double-blind, randomized, placebo-controlled study

    DEFF Research Database (Denmark)

    Aasvang, Eske Kvanner; Hansen, J.B.; Malmstrom, J.

    2008-01-01

    , preclinical, and clinical studies, and may be an effective adjunct to postoperative pain management. METHODS: We performed a single-center, randomized, double-blind, placebo-controlled study of the analgesic efficacy of a single intraoperative wound instillation of 1000 mu g ultrapurified capsaicin (ALGRX.......05), but not for the whole I or 4 wk postoperatively. Mixed-effects analysis with NONMEM revealed that pain scores were significantly lower (P observed, although a mild transient increase in liver enzymes was seen...

  1. Instillation of Hyaluronic Acid via Electromotive Drug Administration Can Improve the Efficacy of Treatment in Patients With Interstitial Cystitis/Painful Bladder Syndrome: A Randomized Prospective Study

    OpenAIRE

    Gülpınar, Ömer; Haliloğlu, Ahmet Hakan; Gökce, Mehmet İlker; Arıkan, Nihat

    2014-01-01

    Purpose In the treatment of interstitial cystitis, intravesical hyaluronic acid application may be suggested as a treatment option. In this randomized prospective study, the authors aimed to identify whether instilling the hyaluronic acid with electromotive drug administration (EMDA) would increase the tissue uptake and improve the efficacy. Materials and Methods The data of 31 patients who had been diagnosed with bladder pain syndrome/interstitial cystitis (BPS/IC) between 2004 and 2005 were...

  2. Compressibility of 304 Stainless Steel Powder Metallurgy Materials Reinforced with 304 Short Stainless Steel Fibers

    Directory of Open Access Journals (Sweden)

    Bibo Yao

    2016-03-01

    Full Text Available Powder metallurgy (P/M technique is usually used for manufacturing porous metal materials. However, some P/M materials are limitedly used in engineering for their performance deficiency. A novel 304 stainless steel P/M material was produced by a solid-state sintering of 304 stainless steel powders and 304 short stainless steel fibers, which were alternately laid in layers according to mass ratio. In this paper, the compressive properties of the P/M materials were characterized by a series of uniaxial compression tests. The effects of fiber content, compaction pressure and high temperature nitriding on compressive properties were investigated. The results indicated that, without nitriding, the samples changed from cuboid to cydariform without damage in the process of compression. The compressive stress was enhanced with increasing fiber content ranging from 0 to 8 wt.%. For compaction pressure from 55 to 75 MPa, greater compaction pressure improved compressive stress. Moreover, high temperature nitriding was able to significantly improve the yield stress, but collapse failure eventually occurred.

  3. Overlaying of type 316 austenitic stainless steel with type 430 ferritic stainless steel

    International Nuclear Information System (INIS)

    Sujith, S.; Gill, T.P.S.

    1993-01-01

    Overlaying of type 316 austenitic stainless steel vessel with type 430 ferritic stainless is proposed for liquid magnesium service. The interface in this type of bimetallic configuration has been shown to be a cause for concern as it contains a hard and brittle martensite micro constituent which becomes susceptible to cracking under certain conditions. This study was carried out to standardize the welding conditions and characterise the interface in order to obtain sound overlay. Some tests were also conducted to simulate the elevated temperature service. The investigation has shown that the interface hardness approaches 400 VPN when no preheating is employed. However, in the preheated samples, appreciable reduction in the peak hardness was observed. This has been attributed to a decrease in the cooling rate of the clad metal with an increase in the preheating temperature which results in softening of the martensite. The minimum recommended preheat is 473 K. The samples exposed to thermal cycle tests to a peak temperature of 1223 K to simulate the service condition did not show any cracking at the interface after 20 cycles of testing. Therefore, this study has demonstrated the stability of the interface between type 316 and 430 stainless steels at the intended temperature of service. (author)

  4. Compressibility of 304 Stainless Steel Powder Metallurgy Materials Reinforced with 304 Short Stainless Steel Fibers.

    Science.gov (United States)

    Yao, Bibo; Zhou, Zhaoyao; Duan, Liuyang; Xiao, Zhiyu

    2016-03-04

    Powder metallurgy (P/M) technique is usually used for manufacturing porous metal materials. However, some P/M materials are limitedly used in engineering for their performance deficiency. A novel 304 stainless steel P/M material was produced by a solid-state sintering of 304 stainless steel powders and 304 short stainless steel fibers, which were alternately laid in layers according to mass ratio. In this paper, the compressive properties of the P/M materials were characterized by a series of uniaxial compression tests. The effects of fiber content, compaction pressure and high temperature nitriding on compressive properties were investigated. The results indicated that, without nitriding, the samples changed from cuboid to cydariform without damage in the process of compression. The compressive stress was enhanced with increasing fiber content ranging from 0 to 8 wt.%. For compaction pressure from 55 to 75 MPa, greater compaction pressure improved compressive stress. Moreover, high temperature nitriding was able to significantly improve the yield stress, but collapse failure eventually occurred.

  5. Cast alumina forming austenitic stainless steels

    Science.gov (United States)

    Muralidharan, Govindarajan; Yamamoto, Yukinori; Brady, Michael P

    2013-04-30

    An austenitic stainless steel alloy consisting essentially of, in terms of weight percent ranges 0.15-0.5C; 8-37Ni; 10-25Cr; 2.5-5Al; greater than 0.6, up to 2.5 total of at least one element selected from the group consisting of Nb and Ta; up to 3Mo; up to 3Co; up to 1W; up to 3Cu; up to 15Mn; up to 2Si; up to 0.15B; up to 0.05P; up to 1 total of at least one element selected from the group consisting of Y, La, Ce, Hf, and Zr; steel alloys is also disclosed.

  6. Electrochemical decontamination of Pu contaminated stainless steel

    International Nuclear Information System (INIS)

    Turner, A.D.; Pottinger, J.S.; Junkison, A.R.

    1983-08-01

    Electrochemical decontamination has been demonstrated to be very effective in removing plutonium nitrate contamination (0.5 μg cm -2 ) on stainless steels. The amount of metal dissolved to achieve a DF of 10 2 to 10 3 was 2 to 7 μm depending on the electrolyte used. In unstirred electrolytes 1M HNO 3 , 1M HNO 3 /0.1M NaF, 5M HNO 3 perform best. Under stirred electrolyte conditions, there is a general marginal fall in effectiveness except for 5M HNO 3 where there is a slight improvement. The optimum performance is a compromise between maximizing the electrolyte throwing power and minimizing substrate surface roughening during decontamination. (author)

  7. Stainless steels for cryogenic bolts and nuts

    International Nuclear Information System (INIS)

    Leroy, F.; Rabbe, P.; Odin, G.

    1975-01-01

    Stainless steel for cryogenic applications are generally austenitic steels which, under the effect of cold-drawing, can or cannot undergo a partial martensitic transformation according to their composition. It has been shown that very high ductility and endurance characteristics at low temperatures, together with very high yield strength and resistances values, can be attained with grades of nitrogenous steels of types Z2CN18-10N and Z3CMN18-8-6N. Optimum ductility values are obtained by employing to the best possible, the martensitic transformations which develop during cold-drawing. From the plotting of the rational traction curves, it is possible to analyse very simply the influence of the composition on the martensitic transformations [fr

  8. Phase identification in neutron irradiated stainless steels

    International Nuclear Information System (INIS)

    Lee, E.H.; Rowcliffe, A.F.

    1980-01-01

    Techniques used for the identification of phases which develop in AISI 316 stainless steel which has been modified by the addition of Ti are described. Five major phases were identified in the alloy containing 0.2 wt % Ti after irradation by 7 x 10 22 n.cm -2 at temperatures ranging from 400 to 650 0 C. Once identification was established from diffraction pattern measurements, subsequent identification could be made by observation of the characteristic shape of each phase combined with the observation of certain characteristic features of te x-ray spectrum of each phase. This combination permitted rapid identification of large numbers of particles necessary for the elucidation of the role of phase instabilities in void swelling

  9. Complex Protection of Vertical Stainless Steel Tanks

    Directory of Open Access Journals (Sweden)

    Fakhrislamov Radik Zakievich

    2014-03-01

    Full Text Available The authors consider the problem of fail-safe oil and oil products storage in stainless steel tanks and present the patented tank inner side protection technology. The latter provides process, ecological and fire safety and reducing soil evaporation of oil products, which is a specific problem. The above-mentioned technology includes corrosion protection and heat insulation protection providing increase of cover durability and RVS service life in general. The offered technological protection scheme is a collaboration of the author, Steel Paint GmbH firm and JSC “Koksokhimmontazhproyekt”. PU foam unicomponent materials of Steel Paint GmbH firm provide the protection of tank inner side and cover.

  10. Segregation effects in welded stainless steels

    International Nuclear Information System (INIS)

    Akhter, J.I.; Shoaid, K.A.; Ahmed, M.; Malik, A.Q.

    1987-01-01

    Welding of steels causes changes in the microstructure and chemical composition which could adversely affect the mechanical and corrosion properties. The report describes the experimental results of an investigation of segregation effects in welded austenitic stainless steels of AISI type 304, 304L, 316 and 316L using the techniques of scanning electron microscopy and electron probe microanalysis. Considerable enhancement of chromium and carbon has been observed in certain well-defined zones on the parent metal and on composition, particularly in the parent metal, in attributed to the formation of (M 23 C 6 ) precipitates. The formation of geometrically well-defined segregation zones is explained on the basis of the time-temperature-precipitation curve of (M 23 C 6 ). (author)

  11. Hydrogenation of stainless steels implanted with nitrogen

    International Nuclear Information System (INIS)

    Silva Ramos, L.E. da.

    1989-01-01

    In the present work the effects of both ion implantation and hydrogenation on the fatigue behaviour of an AISI-304 type unstable stainless steel was studied. The material was tested under the following microstructural conditions: annealed; annealed plus hydrogenated; annealed plus ion-implanted; annealed, ion-implanted and hydrogeneted. The hydrogen induced phase transformations were also studied during the outgassing of the samples. The ion implanted was observed to retard the kinetics of the hydrogen induced phase transformations. It was also observed that the nitrogen ion implantation followed by both natural (for about 4 months) and artificial (100 0 C for 6 hours) aging treatments was beneficial to the fatigue life of both non hydrogenated and severely hydrogenated samples. (author) [pt

  12. Sepse fatal após instilação intravesical de BCG: relato de caso Fatal sepsis after intravesical instillation of BCG: case report

    Directory of Open Access Journals (Sweden)

    Ulysses Vasconcellos de Andrade e Silva

    2011-03-01

    Full Text Available A instilação intravesical do bacilo de Calmette-Guérin (BCG é o tratamento de escolha para carcinoma de bexiga in situ ou tumores superficiais de bexiga de alto grau não invasivos. Este tratamento geralmente é bem tolerado, mas podem ocorrer complicações graves. Paciente idoso, coronariopata, portador de carcinoma superficial de bexiga de alto grau recidivado foi submetido à instilação intravesical de BCG, evoluindo com choque séptico. Recebeu antibioticoterapia de amplo espectro, tuberculostáticos, corticóide, aminas vasoativas, suporte ventilatório e tratamento hemodialítico, sem melhora. Faleceu nove dias após a instilação intravesical de BCG por insuficiência de múltiplos órgãos.Intravesical instillation of bacillus Calmette-Guérin (BCG is the treatment of choice for carcinoma in situ and non-invasive high-grade superficial tumors of the urinary bladder. This treatment is well tolerated overall, but serious complications can occur. An elderly man with coronary disease and recurrent high-grade superficial carcinoma of the bladder underwent intravesical instillation of BCG and developed septic shock. He received wide range antibiotics, tuberculostatic and vasoactive drugs, corticosteroids, mechanical ventilation and renal replacement therapy without improvement. He died nine days after the intravesical instillation of BCG because of multiple organ failure.

  13. [Study on biocompatibility of MIM 316L stainless steel].

    Science.gov (United States)

    Wang, Guohui; Zhu, Shaihong; Li, Yiming; Zhao, Yanzhong; Zhou, Kechao; Huang, Boyun

    2007-04-01

    This study was aimed to evaluate the biocompatibility of metal powder injection molding (MIM) 316L stainless steel. The percentage of S-period cells was detected by flow cytometry after L929 cells being incubated with extraction of MIM 316L stainless steel, and titanium implant materials for clinical application were used as control. In addition, both materials were implanted in animals and the histopathological evaluations were carried out. The statistical analyses show that there are no significant differences between the two groups (P > 0.05), which demonstrate that MIM 316L stainless steel has good biocompatibility.

  14. Kinetics of chemical interactions between zirconium alloys and stainless steels

    International Nuclear Information System (INIS)

    Frecska, J.; Maroti, L.; Matus, L.

    1995-01-01

    The chemical interaction kinetics of reactor core component zirconium alloys and stainless steels at high temperatures was examined. Interaction of as-received and preoxidized Zr1%Nb with X18H10T stainless steel used in WWER type nuclear reactors, and also that of Zircaloy-4 and AISI-316 stainless steel, for comparison, were investigated. The reaction rate measurements were supplemented with post-test metallographical examinations. Results are presented and evaluated, and compared with literature data. (author). 14 refs., 31 figs., 8 tabs

  15. Systemic hypersensitivity reaction to endovascular stainless steel stent.

    Science.gov (United States)

    Univers, Junior; Long, Chandler; Tonks, Stephen A; Freeman, Michael B

    2018-02-01

    Endovascular intervention has become the mainstay for treatment of most patients suffering from peripheral vascular disease. We describe a patient with a known nickel allergy who underwent placement of a stainless steel stent for aortoiliac occlusive disease. Despite our attempt to avoid a nickel-containing stent, the patient developed a diffuse rash consistent with a nickel or metal allergy. A review of stainless steel metallurgy revealed that nickel, cobalt, and titanium are frequently used to provide anticorrosive properties to stainless steel. The clinical significance of the use of nickel-alloy stents in the setting of patients with a nickel allergy is discussed. Published by Elsevier Inc.

  16. Structural Analysis of Cavitation for Different Stainless Steels

    Directory of Open Access Journals (Sweden)

    Mădălina-Elena Mânzână

    2011-09-01

    Full Text Available The cavitation phenomenon is currently approaching all areas of technology and modern industry, where are fluid in motion. In this paper cavitational erosion was conducted on different samples of stainless steels. The cavitation were performed in magnetostrictive vibrating apparatus at Cavitation Laboratory (Polytechnic University of Timisoara. The present paper intends to identify specific structural features in stainless steels. Several investigations were done: macrostructural analysis (Olympus SZX57, scaning electron microscope (Philips SEM and X-ray diffraction (D8 ADVANCE. After quantitative and qualitative investigations structural features were put in evidence on experimental stainless steels.

  17. Fireside carburization of stainless steel furnace tubes

    Energy Technology Data Exchange (ETDEWEB)

    Mirabal, E.; Molina, C. [PDVSA-Refineria Isla, Curayao (Netherlands); Mayorga, A.; Hau, J.L. [PDVSA-Intevep, Caracas (Venezuela)

    1999-11-01

    Most heavy Venezuelan crudes are recognized for having a high total acid number (TAN) that is usually associated with a high tendency to produce naphthenic acid corrosion. To resist this type of corrosion in vacuum heaters, 9Cr-1Mo steel and stainless steels containing molybdenum are usually recommended. In 1993 the original 5Cr-1/2Mo roof tubes of the furnace in a vacuum unit were replaced by stainless steel 316Ti to minimize tube replacement and increase heater reliability. Unexpectedly, some of the new tubes failed after only three years of service, and just one year after undergoing the last turnaround inspection. The damage occurred in the form of deep holes and perforations, starting from the outside tube surface on the fireside. Coke build-up occurred due to severe operating conditions, overheating the tubes on the fireside, above 675 C (1250 F). Metallographic and Scanning Electron Microscopic (SEM) examination revealed internal and external carburization of the material due to the presence of coke and combustion ashes, respectively. The increase in the skin metal temperature facilitated the diffusion of carbon from these carbon-rich deposits into the low carbon content material (0.023 O/O).Depletion of chromium at the grain boundaries due to the massive formation of chromium carbides, resulted in a severe intergranular corrosion attack by molten salts rich in vanadium and sulfur due to asphalt burning. Normal operating practice demands the use of steam for the heater tubes to control coke build-up. This practice had been first reduced and then eliminated, during the past two years prior to the failure, because of economic incentives. This paper describes the root cause analysis conducted to account for these premature tube failures.

  18. Stainless steel-zirconium alloy waste forms

    International Nuclear Information System (INIS)

    McDeavitt, S.M.; Abraham, D.P.; Keiser, D.D. Jr.; Park, J.Y.

    1996-01-01

    An electrometallurgical treatment process has been developed by Argonne National Laboratory to convert various types of spent nuclear fuels into stable storage forms and waste forms for repository disposal. The first application of this process will be to treat spent fuel alloys from the Experimental Breeder Reactor-II. Three distinct product streams emanate from the electrorefining process: (1) refined uranium; (2) fission products and actinides extracted from the electrolyte salt that are processed into a mineral waste form; and (3) metallic wastes left behind at the completion of the electrorefining step. The third product stream (i.e., the metal waste stream) is the subject of this paper. The metal waste stream contains components of the chopped spent fuel that are unaffected by the electrorefining process because of their electrochemically ''noble'' nature; this includes the cladding hulls, noble metal fission products (NMFP), and, in specific cases, zirconium from metal fuel alloys. The selected method for the consolidation and stabilization of the metal waste stream is melting and casting into a uniform, corrosion-resistant alloy. The waste form casting process will be carried out in a controlled-atmosphere furnace at high temperatures with a molten salt flux. Spent fuels with both stainless steel and Zircaloy cladding are being evaluated for treatment; thus, stainless steel-rich and Zircaloy-rich waste forms are being developed. Although the primary disposition option for the actinides is the mineral waste form, the concept of incorporating the TRU-bearing product into the metal waste form has enough potential to warrant investigation

  19. Stainless steel anodes for alkaline water electrolysis and methods of making

    Science.gov (United States)

    Soloveichik, Grigorii Lev

    2014-01-21

    The corrosion resistance of stainless steel anodes for use in alkaline water electrolysis was increased by immersion of the stainless steel anode into a caustic solution prior to electrolysis. Also disclosed herein are electrolyzers employing the so-treated stainless steel anodes. The pre-treatment process provides a stainless steel anode that has a higher corrosion resistance than an untreated stainless steel anode of the same composition.

  20. Comparing Transcervical Intrauterine Lidocaine Instillation with Rectal Diclofenac for Pain Relief During Outpatient Hysteroscopy: A Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Sussan S. Mohammadi

    2015-05-01

    Full Text Available Objectives: There are a number of potential advantages to performing hysteroscopy in an outpatient setting. However, the ideal approach, using local uterine anesthesia or rectal non-steroidal anti-inflammatory drugs, has not been determined. Our objective was to compare the efficacy of intrauterine lidocaine instillation with rectal diclofenac for pain relief during diagnostic hysteroscopy. Methods: We conducted a double-blind randomized controlled trial on 70 nulliparous women with primary infertility undergoing diagnostic hysteroscopy. Subjects were assigned into one of two groups to receive either 100mg of rectal diclofenac or 5mL of 2% intrauterine lidocaine. The intensity of pain was measured by a numeric rating scale 0–10. Pain scoring was performed during insertion of the hysteroscope, during visualization of the intrauterine cavity, and during extrusion of the hysteroscope. Results: There were no statistically significant differences between the groups with regard to the mean pain score during intrauterine visualization (p=0.500. The mean pain score was significantly lower during insertion and extrusion of the hysteroscope in the diclofenac group (p=0.001 and p=0.030, respectively. Nine patients in the lidocaine group and five patients in diclofenac group needed supplementary intravenous propofol injection for sedation (p=0.060. Conclusions: Rectal diclofenac appears to be more effective than intrauterine lidocaine in reducing pain during insertion and extrusion of hysteroscope, but there are no significant statistical and clinical differences between the two methods with regard to the mean pain score during intrauterine inspection.

  1. Evaluation of the respiratory route as a viable portal of entry for Salmonella in poultry via intratracheal challenge of Salmonella Enteritidis and Salmonella Typhimurium.

    Science.gov (United States)

    Kallapura, G; Morgan, M J; Pumford, N R; Bielke, L R; Wolfenden, A D; Faulkner, O B; Latorre, J D; Menconi, A; Hernandez-Velasco, X; Kuttappan, V A; Hargis, B M; Tellez, G

    2014-02-01

    Experimental and epidemiological evidence suggests that primary infection of Salmonella is by the oral-fecal route for poultry. However, the airborne transmission of Salmonella and similar enteric zoonotic pathogens has been historically neglected. Increasing evidence of Salmonella bioaerosol generation in production facilities and studies suggesting the vulnerabilities of the avian respiratory architecture together have indicated the possibility of the respiratory system being a potential portal of entry for Salmonella in poultry. Presently, we evaluated this hypothesis through intratracheal (IT) administration of Salmonella Enteritidis and Salmonella Typhimurium, as separate challenges, in a total of 4 independent trials, followed by enumeration of cfu recovery in ceca-cecal tonsils and recovery incidence in liver and spleen. In all trials, both Salmonella Enteritidis and Salmonella Typhimurium, challenged IT colonized cecae to a similar or greater extent than oral administration at identical challenge levels. In most trials, chickens cultured for cfu enumeration from IT-challenged chicks at same dose as orally challenged, resulted in an increase of 1.5 log higher Salmonella Enteritidis from ceca-cecal tonsils and a much lower dose IT of Salmonella Enteritidis could colonize ceca to the same extent than a higher oral challenge. This trend of increased cecal colonization due to IT challenge was observed with all trails involving week-old birds (experiment 2 and 3), which are widely considered to be more difficult to infect via the oral route. Liver-spleen incidence data showed 33% of liver and spleen samples to be positive for Salmonella Enteritidis administered IT (10(6) cfu/chick), compared with 0% when administered orally (experiment 2, trial 1). Collectively, these data suggest that the respiratory tract may be a largely overlooked portal of entry for Salmonella infections in chickens.

  2. Evaluation of the respiratory route as a viable portal of entry for Salmonella in poultry via intratracheal challenge of Salmonella Enteritidis and Salmonella Typhimurium1

    Science.gov (United States)

    Kallapura, G.; Morgan, M. J.; Pumford, N. R.; Bielke, L. R.; Wolfenden, A. D.; Faulkner, O. B.; Latorre, J. D.; Menconi, A.; Hernandez-Velasco, X.; Kuttappan, V. A.; Hargis, B. M.; Tellez, G.

    2014-01-01

    Experimental and epidemiological evidence suggests that primary infection of Salmonella is by the oral-fecal route for poultry. However, the airborne transmission of Salmonella and similar enteric zoonotic pathogens has been historically neglected. Increasing evidence of Salmonella bioaerosol generation in production facilities and studies suggesting the vulnerabilities of the avian respiratory architecture together have indicated the possibility of the respiratory system being a potential portal of entry for Salmonella in poultry. Presently, we evaluated this hypothesis through intratracheal (IT) administration of Salmonella Enteritidis and Salmonella Typhimurium, as separate challenges, in a total of 4 independent trials, followed by enumeration of cfu recovery in ceca-cecal tonsils and recovery incidence in liver and spleen. In all trials, both Salmonella Enteritidis and Salmonella Typhimurium, challenged IT colonized cecae to a similar or greater extent than oral administration at identical challenge levels. In most trials, chickens cultured for cfu enumeration from IT-challenged chicks at same dose as orally challenged, resulted in an increase of 1.5 log higher Salmonella Enteritidis from ceca-cecal tonsils and a much lower dose IT of Salmonella Enteritidis could colonize ceca to the same extent than a higher oral challenge. This trend of increased cecal colonization due to IT challenge was observed with all trails involving week-old birds (experiment 2 and 3), which are widely considered to be more difficult to infect via the oral route. Liver-spleen incidence data showed 33% of liver and spleen samples to be positive for Salmonella Enteritidis administered IT (106 cfu/chick), compared with 0% when administered orally (experiment 2, trial 1). Collectively, these data suggest that the respiratory tract may be a largely overlooked portal of entry for Salmonella infections in chickens. PMID:24570455

  3. Stress Corrosion Cracking of Type 304 Stainless Steel

    National Research Council Canada - National Science Library

    Louthan, M

    1964-01-01

    Stress corrosion cracking of type 304 stainless steel exposed in dilute chloride solutions is being investigated at the Savannah River Laboratory in attempts to develop a fundamental understanding of the phenomenon...

  4. Enhanced Corrosion Resistance of Stainless Steel Carburized at Low Temperature

    Science.gov (United States)

    Martin, F. J.; Natishan, P. M.; Lemieux, E. J.; Newbauer, T. M.; Rayne, R. J.; Bayles, R. A.; Kahn, H.; Michal, G. M.; Ernst, F.; Heuer, A. H.

    2009-08-01

    The pitting corrosion resistance of surface-modified 316L austenitic stainless steel and N08367 (a “superaustenitic” stainless steel) were evaluated in 0.6 M NaCl solutions and compared to untreated samples of the same materials. The surface modification process used to treat the surfaces was a low-temperature carburization technology termed “low-temperature colossal supersaturation” (LTCSS). The process typically produces surface carbon concentrations of ~15 at. pct without the formation of carbides. The pitting potential of the LTCSS-treated 316L stainless steel in the NaCl solution substantially increased compared to untreated 316L stainless steel, while the pitting behavior of the LTCSS-treated N08367 was unchanged compared to the untreated alloy.

  5. Controlled dissolution of colossal quantities of nitrogen in stainless steel

    DEFF Research Database (Denmark)

    Christiansen, Thomas; Somers, Marcel A. J.

    2006-01-01

    The solubility of nitrogen in austenitic stainless steel was investigated thermogravimetrically by equilibrating thin foils of AISI 304 and AISI 316 in ammonia/hydrogen gas mixtures. Controlled dissolution of colossal amounts of nitrogen under metastable equilibrium conditions was realized...

  6. Strengthening of stainless steel weldment by high temperature precipitation

    Directory of Open Access Journals (Sweden)

    Sergio Neves Monteiro

    2017-10-01

    Full Text Available The mechanical behavior and the strengthening mechanism of stainless steel welded joints at 600 °C have been investigated. The welds were composed of AISI 304 stainless steel, as base metal, and niobium containing AISI 347 stainless steel, as weld metal. The investigation was conducted by means of creep tests. The welded specimens were subjected to both high temperature (600 °C and long periods (up to 2000 h under constant load, and both mechanical properties and microstructural changes in the material were monitored. It was found that the exposure of the material at 600 °C under load contributes to a strengthening effect on the weld. The phenomenon might be correlated with an accelerated process of second phase precipitation hardening. Keywords: Stainless steel, Weld, AISI 304, Precipitation hardening

  7. Stainless steels in power plant and plant construction. Papers

    International Nuclear Information System (INIS)

    1994-01-01

    The conference report comprises 14 papers on the corrosion characteristics of stainless steels in power plant and plant engineering. 9 papers are available as separate records in the ENERGY database. (MM) [de

  8. Stress-Corrosion Cracking in Martensitic PH Stainless Steels

    Science.gov (United States)

    Humphries, T.; Nelson, E.

    1984-01-01

    Precipitation-hardening alloys evaluated in marine environment tests. Report describes marine-environment stress-corrosion cracking (SCC) tests of three martensitic precipitation hardening (PH) stainless-steel alloys.

  9. Development of oxide dispersion strengthened 2205 duplex stainless steel composite

    Directory of Open Access Journals (Sweden)

    Oladayo OLANIRAN

    2015-05-01

    Full Text Available Composites of duplex stainless steel were produced by oxide dispersion strengthening with comparatively improved mechanical properties by hot press sintering of partially stabilized Zirconia (PSZ, 3% yttria, mole fraction dispersion in 2205 duplex stainless steels. Ceramic oxide was added as reinforcement, while chromium (Cr and Nickel (Ni were incorporated to maintain the austenitic/ferritic phase balance of the duplex stainless steel. The powders and sintered were characterized in detail using scanning electron microscopy (SEM and X-ray diffraction (XRD. The microstructural evolution and phase formation during oxide dispersion strengthening of duplex stainless steel composites were investigated. The influence of composition variation of the reinforcements on the microstructural and corrosion behaviour in simulated mine water of the composites were investigated. In this manuscript, it was established that composition has great influence on the structure/properties relationship of the composites developed.

  10. HIP bonding between niobium/copper/stainless steel materials

    International Nuclear Information System (INIS)

    Inoue, Hitoshi; Fujino, Takeo; Hitomi, Nobuteru; Saito, Kenji; Yamada, Masahiro; Shibuya, Junichi; Ota, Tomoko

    2000-01-01

    We have used niobium flanges for the niobium bulk superconducting RF cavities, however, they are expensive. Stainless steel flanges instead of the niobium flanges will be used in the future large scale production of sc cavities like the KEK/JAERI joint project. For a future R and D of the vacuum sealing related to the clean horizontal assembly method or development of cavities welded a helium vessel in the KEK/JAERI joint project, a converter section of niobium material to stainless steel is required. From these requirements we need to develop the converter. We have tried a HIP bonding method between niobium materials and stainless steel or copper material. It was made clear that the technology could offer an enough bonding strength even higher than niobium tensile strength in the joined surface between niobium and stainless steel or copper. (author)

  11. A Study of Localized Corrosion in Supermartensitic Stainless Steel Weldments

    OpenAIRE

    Enerhaug, Jakob

    2002-01-01

    This doctoral thesis is concerned with pitting corrosion in super martensitic stainless steel (SMSS) weldments in slightly sour service. Thee main objective with the present thesis has been to find out why pitting corrosion occurs in the heat affected zone (HAZ) at ambient rather than at elevated temperatures and how the corrosion mechanism depends on the welding process. The thesis is divided into six parts. Part I gives a general introduction to martensitic stainless steels, focusing on...

  12. Nickel release from nickel-plated metals and stainless steels.

    Science.gov (United States)

    Haudrechy, P; Foussereau, J; Mantout, B; Baroux, B

    1994-10-01

    Nickel release from nickel-plated metals often induces allergic contact dermatitis, but, for nickel-containing stainless steels, the effect is not well-known. In this paper, AISI 304, 316L, 303 and 430 type stainless steels, nickel and nickel-plated materials were investigated. 4 tests were performed: patch tests, leaching experiments, dimethylglyoxime (DMG) spot tests and electrochemical tests. Patch tests showed that 96% of the patients were intolerant to Ni-plated samples, and 14% to a high-sulfur stainless steel (303), while nickel-containing stainless steels with a low sulfur content elicited no reactions. Leaching experiments confirmed the patch tests: in acidic artificial sweat, Ni-plated samples released about 100 micrograms/cm2/week of nickel, while low-sulfur stainless steels released less than 0.03 microgram/cm2/week of nickel, and AISI 303 about 1.5 micrograms/cm2/week. Attention is drawn to the irrelevance of the DMG spot test, which reveals Ni present in the metal bulk but not its dissolution rate. Electrochemical experiments showed that 304 and 316 grades remain passive in the environments tested, while Ni-plated steels and AISI 303 can suffer significant cation dissolution. Thus, Ni-containing 304 and 316 steels should not induce contact dermatitis, while 303 should be avoided. A reliable nitric acid spot test is proposed to distinguish this grade from other stainless steels.

  13. Solidification behavior of austenitic stainless steel filler metals

    International Nuclear Information System (INIS)

    David, S.A.; Goodwin, G.M.; Braski, D.N.

    1980-02-01

    Thermal analysis and interrupted solidification experiments on selected austenitic stainless steel filler metals provided an understanding of the solidification behavior of austenitic stainless steel welds. The sequences of phase separations found were for type 308 stainless steel filler metal, L + L + delta + L + delta + γ → γ + delta, and for type 310 stainless steel filler metal, L → L + γ → γ. In type 308 stainless steel filler metal, ferrite at room temperature was identified as either the untransformed primary delta-ferrite formed during the initial stages of solidification or the residual ferrite after Widmanstaetten austenite precipitation. Microprobe and scanning transmission electron microscope microanalyses revealed that solute extensively redistributes during the transformation of primary delta-ferrite to austenite, leading to enrichment and stabilization of ferrite by chromium. The type 310 stainless steel filler metal investigated solidifies by the primary crystallization of austenite, with the transformation going to completion at the solidus temperature. In our samples residual ferrite resulting from solute segregation was absent at the intercellular or interdendritic regions

  14. Plasma spot welding of ferritic stainless steels

    Directory of Open Access Journals (Sweden)

    Lešnjak, A.

    2002-06-01

    Full Text Available Plasma spot welding of ferritic stainless steels is studied. The study was focused on welding parameters, plasma and shielding gases and the optimum welding equipment. Plasma-spot welded overlap joints on a 0.8 mm thick ferritic stainless steel sheet were subjected to a visual examination and mechanical testing in terms of tension-shear strength. Several macro specimens were prepared. Plasma spot welding is suitable to use the same gas as shielding gas and as plasma gas, i.e., a 98 % Ar/2 % H 2 gas mixture. Tension-shear strength of plasma-spot welded joints was compared to that of resistance-spot welded joints. It was found that the resistance welded joints withstand a somewhat stronger load than the plasma welded joints due to a larger weld spot diameter of the former. Strength of both types of welded joints is approximately the same.

    El artículo describe el proceso de soldeo de aceros inoxidables ferríticos por puntos con plasma. La investigación se centró en el establecimiento de los parámetros óptimos de la soldadura, la definición del gas de plasma y de protección más adecuado, así como del equipo óptimo para la realización de la soldadura. Las uniones de láminas de aceros inoxidables ferríticos de 0,8 mm de espesor, soldadas a solape por puntos con plasma, se inspeccionaron visualmente y se ensayaron mecánicamente mediante el ensayo de cizalladura por tracción. Se realizaron macro pulidos. Los resultados de la investigación demostraron que la solución más adecuada para el soldeo por puntos con plasma es elegir el mismo gas de plasma que de protección. Es decir, una mezcla de 98 % de argón y 2 % de hidrógeno. La resistencia a la cizalladura por tracción de las uniones soldadas por puntos con plasma fue comparada con la resistencia de las uniones soldadas por resistencia por puntos. Se llegó a la conclusión de que las uniones soldadas por resistencia soportan una carga algo mayor que la uniones

  15. Phase Transformations in Cast Duplex Stainless Steels

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yoon-Jun [Iowa State Univ., Ames, IA (United States)

    2004-01-01

    Duplex stainless steels (DSS) constitute both ferrite and austenite as a matrix. Such a microstructure confers a high corrosion resistance with favorable mechanical properties. However, intermetallic phases such as σ and χ can also form during casting or high-temperature processing and can degrade the properties of the DSS. This research was initiated to develop time-temperature-transformation (TTT) and continuous-cooling-transformation (CCT) diagrams of two types of cast duplex stainless steels, CD3MN (Fe-22Cr-5Ni-Mo-N) and CD3MWCuN (Fe-25Cr-7Ni-Mo-W-Cu-N), in order to understand the time and temperature ranges for intermetallic phase formation. The alloys were heat treated isothermally or under controlled cooling conditions and then characterized using conventional metallographic methods that included tint etching, and also using electron microscopy (SEM, TEM) and wavelength dispersive spectroscopy (WDS). The kinetics of intermetallic-phase (σ + χ) formation were analyzed using the Johnson-Mehl-Avrami (MA) equation in the case of isothermal transformations and a modified form of this equation in the case of continuous cooling transformations. The rate of intermetallic-phase formation was found to be much faster in CD3MWCuN than CD3MN due mainly to differences in the major alloying contents such as Cr, Ni and Mo. To examine in more detail the effects of these elements of the phase stabilities; a series of eight steel castings was designed with the Cr, Ni and Mo contents systematically varied with respect to the nominal composition of CD3MN. The effects of varying the contents of alloying additions on the formation of intermetallic phases were also studied computationally using the commercial thermodynamic software package, Thermo-Calc. In general, σ was stabilized with increasing Cr addition and χ by increasing Mo addition. However, a delicate balance among Ni and other minor elements such as N and Si also exists. Phase equilibria in DSS can be affected by

  16. Phase transformations in cast duplex stainless steels

    Science.gov (United States)

    Kim, Yoon-Jun

    Duplex stainless steels (DSS) constitute both ferrite and austenite as a matrix. Such a microstructure confers a high corrosion resistance with favorable mechanical properties. However, intermetallic phases such as sigma (sigma) and chi (chi) can also form during casting or high-temperature processing and can degrade the properties of the DSS. This research was initiated to develop time-temperature-transformation (TTT) and continuous-cooling-transformation (CCT) diagrams of two types of cast duplex stainless steels, CD3MN (Fe-22Cr-5Ni-Mo-N) and CD3MWCuN (Fe-25Cr-7Ni-Mo-W-Cu-N), in order to understand the time and temperature ranges for intermetallic phase formation. The alloys were heat treated isothermally or under controlled cooling conditions and then characterized using conventional metallographic methods that included tint etching, and also using electron microscopy (SEM, TEM) and wavelength dispersive spectroscopy (WDS). The kinetics of intermetallic-phase (sigma + chi) formation were analyzed using the Johnson-Mehl-Avrami (JMA) equation in the case of isothermal transformations and a modified form of this equation in the case of continuous cooling transformations. The rate of intermetallic-phase formation was found to be much faster in CD3MWCuN than CD3MN due mainly to differences in the major alloying contents such as Cr, Ni and Mo. To examine in more detail the effects of these elements of the phase stabilities, a series of eight steel castings was designed with the Cr, Ni and Mo contents systematically varied with respect to the nominal composition of CD3MN. The effects of varying the contents of alloying additions on the formation of intermetallic phases were also studied computationally using the commercial thermodynamic software package, Thermo-Calc. In general, a was stabilized with increasing Cr addition and chi by increasing Mo addition. However, a delicate balance among Ni and other minor elements such as N and Si also exists. Phase equilibria in

  17. EFFECT OF INTERMETALLIC PHASES ON CORROSION BEHAVIOR AND MECHANICAL PROPERTIES OF DUPLEX STAINLESS STEEL AND SUPER-DUPLEX STAINLESS STEEL

    OpenAIRE

    Prabhu Paulraj; Rajnish Garg

    2015-01-01

    Duplex Stainless Steels (DSS) and Super Duplex Stainless Steel (SDSS) have excellent integration of mechanical and corrosion properties. However, the formation of intermetallic phases is a major problem in their usage. The mechanical and corrosion properties are deteriorated due to the presence of intermetallic phases. These phases are induced during welding, prolonged exposure to high temperatures, and improper heat treatments. The main emphasis of this review article is on intermetallic pha...

  18. Martensite transformation in antimony implanted stainless steel

    International Nuclear Information System (INIS)

    Johnson, E.; Littmark, U.; Johansen, A.; Christodoulides, C.

    1981-01-01

    The authors have used Rutherford backscattering analysis (RBS) and transmission electron microscopy (TEM) and diffraction to investigate austenitic stainless steel crystals implanted at room temperature with 80 keV Sb + ions to a fluence of 5 x 10 20 ions/m 2 , thus providing implantation with a heavy group V element. RBS channeling spectra from implanted crystals show a damage peak which approaches the height of the random level and therefore indicates a very high degree of disorder in the implanted layers. The distribution of the disorder extends to a depth 3-5 times the depth of the primary radiation damage. The Sb peaks under channeling as well as random conditions are indistinguishable, confirming that substitutionality during implantation is negligible. To establish the nature of the disorder which cannot be assessed from the RBS analysis alone, and in particular to assess whether an amorphous alloy is formed in the implanted layer as indicated from the RBS spectra, samples implanted under similar conditions were investigated in the TEM. Significant extra spots in the patterns can be ascribed to the presence of a radiation induced b.c.c. phase of martensitic origin. The result that a significant amount of martensite can be induced by antimony implantation seems to indicate that the main driving force for the transition is due to damage induced stress concentrations. (Auth.)

  19. Nonmetallic inclusions in JBK-75 stainless steel

    International Nuclear Information System (INIS)

    Brewer, A.W.; Krenzer, R.W.; Doyle, J.H.; Riefenberg, D.H.

    1977-01-01

    Stainless steel alloys that are chemically complex, such as A-286 or JBK-75, are designed to improve such high-temperature properties as strength. This is accomplished by precipitating secondary phases during aging. Such multicomponent systems, however, can also produce undesirable phases that are detrimental to forgeability and final mechanical properties. Cast segregation and numerous nonmetallic inclusions can have a degrading influence on the toughness and ductility of the alloy. Several different heats of A-286 and JBK-75 were studied, and titanium carbide and/or molybdenum carbide [(Ti, Mo)C] plus titanium carbide and/or titanium carbonitride Ti(C,N)-type phases were qualitatively identified as the major nonmetallic constituent in these alloys. The common procedure for rating the microcleanliness of steels does not classify such carbide or carbonitride phases and thus does not provide an appropriate means of controlling in-process inspection. The results of this study are discussed in terms of alternative methods for evaluating the microcleanliness of superalloys

  20. Austenitic stainless steel for high temperature applications

    International Nuclear Information System (INIS)

    Johnson, G. D.; Powell, R. W.

    1985-01-01

    This invention describes a composition for an austenitic stainless steel which has been found to exhibit improved high temperature stress rupture properties. The composition of this alloy is about (in wt. %): 12.5 to 14.5 Cr; 14.5 to 16.5 Ni; 1.5 to 2.5 Mo; 1.5 to 2.5 Mn; 0.1 to 0.4 Ti; 0.02 to 0.08 C; 0.5 to 1.0 Si; 0.01 maximum, N; 0.02 to 0.008 P; 0.002 to 0.008 B; 0.004-0.0010 S; 0.02-0.05 Nb; 0.01-0.05 V; 0.005-0.02 Ta; 0.02-0.05 Al; 0.01-0.04 Cu; 0.02-0.05 Co; 0.03 maximum, As; 0.01 maximum, O; 0.01 maximum, Zr; and with the balance of the alloy being essentially iron. The carbon content of the alloy is adjusted such that wt. % Ti/(wt. % C+wt. % N) is between 4 and 6, and most preferably about 5. In addition the sum of the wt. % P+wt. % B+wt. % S is at least 0.03 wt. %. This alloy is believed to be particularly well suited for use as fast breeder reactor fuel element cladding

  1. Plasticity of low carbon stainless steels

    International Nuclear Information System (INIS)

    Bulat, S.I.; Fel'dgandler, Eh.G.; Kareva, E.N.

    1975-01-01

    In the temperature range 800-1200 0 C and with strain rates of from 10 -3 to 3 s -1 , austenitic (000Kh18N12) and austenitic-ferrite (000Kh26N6) very low carbon stainless steels containing 0.02-0.03% C exhibit no higher resilience than corresponding ordinary steels containing 0.10-0.12% C. However, the plasticity of such steels (particularly two-phase steels) at 900-1100 0 C is appreciably inferior owing to the development of intergranular brittle fracture. Pressure treatment preceded by partial cooling of the surface to 850 0 C yields rolled and forged products with acceptable indices but is inconvenient technically. At the Zlatoustovsk and Ashin metallurgical plants successful tests have been performed involving the forging and rolling of such steels heated to 1280-1300 0 C without partial cooling; it was necessary to improve the killing conditions, correct the chemical composition (increasing the proportion of ferrite) and take measures against heat loss. (author)

  2. New Economical 19Cr Duplex Stainless Steels

    Science.gov (United States)

    Li, Jun; Zhang, Zixing; Chen, Hong; Xiao, Xueshan; Zhao, Junliang; Jiang, Laizhu

    2012-02-01

    New economical duplex stainless steels (DSSs) containing 19Cr-6Mn- xNi-1.0Mo-0.5W-0.5Cu-0.2N ( x = 0.5 to 2.0) were developed, and the microstructure, impact property, and corrosion resistance of the alloys were studied. The ferrite content increases with the solution treatment temperature, but decreases with an increase in nickel. The sigma phase is not found precipitating in the alloys treated with solution from 1023 K to 1523 K (750 °C to 1250 °C). The low-temperature impact energy of the experimental alloys increases first and then decreases rapidly with an increase in nickel, which is mainly due to the martensite transformation with an increase in austenite. The alloys have a better mechanical property and pitting corrosion resistance than AISI 304. Among the designed DSS alloys, 19Cr-6Mn-1.3Ni-1.0Mo-0.5W-0.5Cu-0.2N is found to be an optimum alloy with proper phase proportion, a better combination of mechanical strength and elongation, and higher pitting corrosion resistance compared with those of the other alloys.

  3. Corrosion behaviour of sintered duplex stainless steels

    Energy Technology Data Exchange (ETDEWEB)

    Utrilla, M. Victoria; Urena, Alejandro; Otero, Enrique; Munez, Claudio Jose [Escuela Superior de Ciencias Experimentales y Tecnologia, Universidad Rey Juan Carlos, C/ Tulipan s/n, 28933 Mostoles, Madrid (Spain)

    2004-07-01

    Duplex austenite-ferrite stainless steels were prepared by mixing austenitic (316L) and ferritic (434L) atomized powders. Although different 316L/434L ratios were prepared, present work centred its study on 50% ferrite - 50% austenite sintered steel. The powders were mixed and pressed at 700 MPa and sintered at 1250 deg. C for 30 min in vacuum. The cooling rate was 5 deg. C/min. Solution treatment was carried out to homogenize the microstructure at 1100 deg. C during 20 min. A microstructural study of the material in solution was performed, evaluating the microstructure, proportion and shape of porosity, and ferrite percentage. This last was measured by two methods, quantitative metallography and Fischer ferrito-metry. The materials were heat treated in the range of 700 to 1000 deg. C, for 10, 30 and 60 min and water quenched, to study the microstructural changes and the influence on the intergranular corrosion resistance. The method used to evaluate the sensitization to the intergranular corrosion was the electrochemical potentio-kinetic reactivation procedure (EPR). The test solution was 0.5 M H{sub 2}SO{sub 4} + 0,01 M KSCN at 30 deg. C. The criterion used to evaluate the sensitization was the ratio between the maximum reactivation density (Ir) and the maximum activation density (Ia). The results of the electrochemical tests were discussed in relation with the microstructures observed at the different heat treatments. (authors)

  4. Fracture toughness of stainless steel welds

    International Nuclear Information System (INIS)

    Mills, W.J.

    1985-11-01

    The effects of temperature, composition and weld-process variations on the fracture toughness behavior for Types 308 and 16-8-2 stainless steel (SS) welds were examined using the multiple-specimen J/sub R/-curve procedure. Fracture characteristics were found to be dependent on temperature and weld process but not on filler material. Gas-tungsten-arc (GTA) welds exhibited the highest fracture toughness, a shielded metal-arc (SMA) weld exhibited an intermediate toughness and submerged-arc (SA) welds yielded the lowest toughness. Minimum-expected fracture properties were defined from lower-bound J/sub c/ and tearing modulus values generated here and in previous studies. Fractographic examination revealed that microvoid coalescence was the operative fracture mechanism for all welds. Second phase particles of manganese silicide were found to be detrimental to the ductile fracture behavior because they separated from the matrix during the initial stages of plastic straining. In SA welds, the high density of inclusions resulting from silicon pickup from the flux promoted premature dimple rupture. The weld produced by the SMA process contained substantially less manganese silicide, while GTA welds contained no silicide inclusions. Delta ferrite particles present in all welds were substantially more resistant to local failure than the silicide phase. In welds containing little or no manganese silicide, delta ferrite particles initiated microvoid coalescence but only after extensive plastic straining

  5. Neurotoxicity of low-dose repeatedly intranasal instillation of nano- and submicron-sized ferric oxide particles in mice

    Energy Technology Data Exchange (ETDEWEB)

    Wang Bing; Feng Weiyue, E-mail: fengwy@mail.ihep.ac.cn; Zhu Motao; Wang Yun; Wang Meng [Chinese Academy of Sciences, Laboratory for Bio-Environmental Effects of Nanomaterials and Nanosafety and Key Laboratory of Nuclear Analytical Techniques, Institute of High Energy Physics (China); Gu Yiqun [Maternity Hospital of Haidian District (China); Ouyang Hong; Wang Huajian; Li Ming; Zhao Yuliang, E-mail: zhaoyuliang@mail.ihep.ac.cn; Chai Zhifang [Chinese Academy of Sciences, Laboratory for Bio-Environmental Effects of Nanomaterials and Nanosafety and Key Laboratory of Nuclear Analytical Techniques, Institute of High Energy Physics (China); Wang Haifang [Peking University, College of Chemistry and Molecular Engineering (China)

    2009-01-15

    Olfactory tract has been demonstrated to be an important portal for inhaled solid nanoparticle transportation into the central nervous system (CNS). We have previously demonstrated that intranasally instilled Fe{sub 2}O{sub 3} nanoparticles could transport into the CNS via olfactory pathway. In this study, we investigated the neurotoxicity and size effect of repeatedly low-dose (130 {mu}g) intranasal exposure of nano- and submicron-sized Fe{sub 2}O{sub 3} particles (21 nm and 280 nm) to mice. The biomarkers of oxidative stress, activity of nitric oxide synthases and release of monoamine neurotransmitter in the brain were studied. Our results showed that significant oxidative stress was induced by the two sizes of Fe{sub 2}O{sub 3} particles. The activities of GSH-Px, Cu,Zn-SOD, and cNOS significantly elevated and the total GSH and GSH/GSSG ratio significantly decreased in the olfactory bulb and hippocampus after the nano- and submicron-sized Fe{sub 2}O{sub 3} particle treatment (p < 0.05). The nano-sized Fe{sub 2}O{sub 3} generally induced greater alteration and more significant dose-effect response than the submicron-sized particle did. Some slight perturbation of monoamine neurotransmitters were found in the hippocampus after exposure to the two sizes of Fe{sub 2}O{sub 3} particle. The TEM image showed that some ultrastructural alterations in nerve cells, including neurodendron degeneration, membranous structure disruption and lysosome increase in the olfactory bulb, slight dilation in the rough endoplasmic reticulum and lysosome increase in the hippocampus were induced by the nano-sized Fe{sub 2}O{sub 3} treatment. In contrast, in the submicron-sized Fe{sub 2}O{sub 3} treated mice, slightly swollen mitochondria and some vacuoles were observed in the olfactory bulb and hippocampus, respectively. These results indicate that intranasal exposure of Fe{sub 2}O{sub 3} nanoparticles could induce more severe oxidative stress and nerve cell damage in the brain than the

  6. Effects of microstructure on ultrasonic examination of stainless steel

    International Nuclear Information System (INIS)

    Kupperman, D.S.; Reimann, K.J.

    1976-01-01

    Ultrasonic inspection of cast stainless steel components or stainless steel welds is difficult, and the results obtained are hard to interpret. The present study describes the effects of stainless steel microstructure on ultrasonic test results. Welded coupons, 2.5 and 5.0 cm thick, were fabricated from Type 304 stainless steel, with Type 308 stainless steel as the weld material. Metallography of the base material shows grain sizes of 15 and 80 μm, and dendrites aligned from the top to the bottom surface in cast material. X-ray diffraction and ultrasonic velocity measurements indicate a random crystal orientation in the base material, but the cast sample had aligned dendrites. The weld material exhibits a dendritic structure with a preferred (100) direction perpendicular to the weld pass. Spectral analysis of ultrasonic broad-band signals through the base materials shows drastic attenuation of higher frequencies with increasing grain size (Rayleigh scattering). Annealing and recrystallization increases the ultrasonic attenuation and produces carbide precipitation at grain boundaries. The microstructural differences of the base metal, heat-affected zone, and weld metal affect the amplitude of ultrasonic reflections from artificial flaws in these zones. Data obtained from two samples of different grain sizes indicate that grain size has little effect when a 1-MHz transducer is used. When going from a 15 to an 80-μm crystalline structure, a 5-MHz unit suffers a 30-dB attenuation in the detection of a 1.2 mm deep notch. The anisotropy of the dendritic structure in stainless steel renewed the interest in the effect of shear-wave polarization. In the (110) crystallographic orientation of stainless steel, two modes of shear waves can be generated, which have velocities differing by a factor of two. This effect may be helpful in ''tuning'' of shear waves by polarization to obtain better penetration in large grain materials such as welds

  7. Surface modification does not influence the genotoxic and inflammatory effects of TiO2 nanoparticles after pulmonary exposure by instillation in mice

    DEFF Research Database (Denmark)

    Wallin, Håkan; Kyjovska, Zdenka O.; Poulsen, Sarah S.

    2016-01-01

    for comparison. The cellular composition and protein concentration were determined in bronchoalveolar lavage (BAL) fluid as markers for an inflammatory response. Pulmonary and systemic genotoxicity was analysed by the alkaline comet assay as DNA strand breaks in BAL cells, lung and liver tissue. The pulmonary...... instillation. NRCWE-001 was unmodified rutile TiO2 with endogenous negative surface charge, whereas NRCWE-002 was surface modified to be positively charged. C57BL/6J BomTac mice received 18, 54 and 162 µg/mouse and were humanely killed 1, 3 and 28 days post-exposure. Vehicle controls were tested alongside...

  8. A Prospective, Multicenter, Double-Blind, Randomized Trial of Bladder Instillation of Liposome Formulation OnabotulinumtoxinA for Interstitial Cystitis/Bladder Pain Syndrome.

    Science.gov (United States)

    Chuang, Yao-Chi; Kuo, Hann-Chorng

    2017-08-01

    Intravesical instillation of liposomal formulated botulinum toxin A (lipotoxin) has shown therapeutic effects as treatment of refractory overactive bladder without needle injections. We assessed lipotoxin to treat refractory interstitial cystitis/bladder pain syndrome. This 2-center, double-blind, randomized, placebo controlled, physician initiated study enrolled patients with refractory interstitial cystitis/bladder pain syndrome. A total of 31 patients were assigned to intravesical instillation of lipotoxin (onabotulinumtoxinA 200 U with 80 mg sphingomyelin), 28 were assigned to onabotulinumtoxinA 200 U in normal saline and 31 were assigned to normal saline alone. The primary end point was the average change in O'Leary-Sant symptom scores, including ICSI (Interstitial Cystitis Symptom Index) and ICPI (Interstitial Cystitis Problem Index) between baseline and 4 weeks after treatment. Other end points included the average changes in a 3-day voiding diary, a visual analog scale for pain and a global response assessment of patient satisfaction. Improvements in the pain scale and O'Leary-Sant symptom scores occurred in all 3 groups by 4 weeks after treatment. Lipotoxin instillation was associated with a statistically significant decrease in O'Leary-Sant symptom scores (mean ± SD 7.38 ± 8.75), ICSI (4.00 ± 4.28), ICPI (3.35 ± 5.11) and the visual analog scale pain scale (1.64 ± 2.52), and an increase in the global response assessment (1.35 ± 1.28). However, there was no difference in improvement among the 3 groups. No significant adverse events were found in any group. Lipotoxin failed to demonstrate a positive proof of concept compared to onabotulinumtoxinA or placebo. However, a single intravesical instillation of lipotoxin was associated with decreased interstitial cystitis/bladder pain syndrome symptoms compared to baseline in patients with moderate to severe interstitial cystitis/bladder pain syndrome. The effect was likely due to a significant placebo

  9. Antibacterial effect of silver nanofilm modified stainless steel surface

    Science.gov (United States)

    Fang, F.; Kennedy, J.; Dhillon, M.; Flint, S.

    2015-03-01

    Bacteria can attach to stainless steel surfaces, resulting in the colonization of the surface known as biofilms. The release of bacteria from biofilms can cause contamination of food such as dairy products in manufacturing plants. This study aimed to modify stainless steel surfaces with silver nanofilms and to examine the antibacterial effectiveness of the modified surface. Ion implantation was applied to produce silver nanofilms on stainless steel surfaces. 35 keV Ag ions were implanted with various fluences of 1 × 1015 to 1 × 1017 ions•cm-2 at room temperature. Representative atomic force microscopy characterizations of the modified stainless steel are presented. Rutherford backscattering spectrometry spectra revealed the implanted atoms were located in the near-surface region. Both unmodified and modified stainless steel coupons were then exposed to two types of bacteria, Pseudomonas fluorescens and Streptococcus thermophilus, to determine the effect of the surface modification on bacterial attachment and biofilm development. The silver modified coupon surface fluoresced red over most of the surface area implying that most bacteria on coupon surface were dead. This study indicates that the silver nanofilm fabricated by the ion implantation method is a promising way of reducing the attachment of bacteria and delay biofilm formation.

  10. Work of adhesion of dairy products on stainless steel surface

    Directory of Open Access Journals (Sweden)

    Patrícia Campos Bernardes

    2012-12-01

    Full Text Available The adhesion of the solids presents in food can difficult the process of surface cleaning and promotes the bacterial adhesion process and can trigger health problems. In our study, we used UHT whole milk, chocolate based milk and infant formula to evaluate the adhesion of Enterobacter sakazakii on stainless steel coupons, and we determine the work of adhesion by measuring the contact angle as well as measured the interfacial tension of the samples. Inaddition we evaluated the hydrophobicity of stainless steel after pre-conditioning with milk samples mentioned. E. sakazakii was able to adhere to stainless steel in large numbers in the presence of dairy products. The chocolate based milk obtained the lower contact angle with stainless steel surface, higher interfacial tension and consequently higher adhesion work. It was verified a tendency of decreasing the interfacial tension as a function of the increasing of protein content. The pre-conditioning of the stainless steel coupons with milk samples changed the hydrophobic characteristics of the surfaces and became them hydrophilic. Therefore, variations in the composition of the milk products affect parameters important that can influence the procedure of hygiene in surface used in food industry.

  11. Optimization of the A-TIG welding for stainless steels

    Science.gov (United States)

    Jurica, M.; Kožuh, Z.; Garašić, I.; Bušić, M.

    2018-03-01

    The paper presents the influence of the activation flux and shielding gas on tungsten inert gas (A-TIG) welding of the stainless steel. In introduction part, duplex stainless steel was analysed. The A-TIG process was explained and the possibility of welding stainless steels using the A-TIG process to maximize productivity and the cost-effectiveness of welded structures was presented. In the experimental part duplex, 7 mm thick stainless steel has been welded in butt joint. The influence of activation flux chemical composition upon the weld penetration has been investigated prior the welding. The welding process was performed by a robot with TIG equipment. With selected A-TIG welding technology preparation of plates and consumption of filler material (containing Cr, Ni and Mn) have been avoided. Specimens sectioned from the produced welds have been subjected to tensile strength test, macrostructure analysis and corrosion resistance analysis. The results have confirmed that this type of stainless steel can be welded without edge preparation and addition of filler material containing critical raw materials as Cr, Ni and Mn when the following welding parameters are set: current 200 A, welding speed 9,1 cm/min, heat input 1,2 kJ/mm and specific activation flux is used.

  12. Growth of MWCNTs on Flexible Stainless Steels without Additional Catalysts

    Directory of Open Access Journals (Sweden)

    Udomdej Pakdee

    2017-01-01

    Full Text Available Multiwalled carbon nanotubes (MWCNTs were synthesized on austenitic stainless steel foils (Type 304 using a home-built thermal chemical vapor deposition (CVD under atmospheric pressure of hydrogen (H2 and acetylene (C2H2. During the growth, the stainless steel substrates were heated at different temperatures of 600, 700, 800, and 900°C. It was found that MWCNTs were grown on the stainless steel substrates heated at 600, 700, and 800°C while amorphous carbon film was grown at 900°C. The diameters of MWCNTs, as identified by scanning electron microscope (SEM images together with ImageJ software program, were found to be 67.7, 43.0, and 33.1 nm, respectively. The crystallinity of MWCNTs was investigated by an X-ray diffractometer. The number of graphitic walled layers and the inner diameter of MWCNTs were investigated using a transmission electron microscope (TEM. The occurrence of Fe3O4 nanoparticles associated with carbon element can be used to reveal the behavior of Fe in stainless steel as catalyst. Raman spectroscopy was used to confirm the growth and quality of MWCNTs. The results obtained in this work showed that the optimum heated stainless steel substrate temperature for the growth of effective MWCNTs is 700°C. Chemical states of MWCNTs were investigated by X-ray photoelectron spectroscopy (XPS using synchrotron light.

  13. Precipitation reactions in austenitic stainless steels

    International Nuclear Information System (INIS)

    Hoch, M.; Yung-Shih Chen

    1979-01-01

    The precipitation reactions for commercial austenitic stainless steels (AISI type 347, 321, 316, 316L, 304 and 304L) and Ti-modified AISI type 316 SS were studied in the temperature range of 750 0 C-1350 0 C. Specimens were held at the temperature for 15 to 25 hours to ensure that equilibrium conditions were reached and followed by a water quench to prevent further precipitation reactions during cooling process. The precipitates were extracted from bulk specimens by anodic dissolution and identified by x-ray diffraction analysis. In Ti-stabilized 321 SS, large TiN and Ti 2 S (Ti 4 C 2 S2) precipitates were present in solution treated and subsequent annealed specimens. Small TiC precipitates were present in specimens annealed below 1150 0 C. The M 23 C 6 precipitates were found to be present after annealing at 850 0 C for 25 hours. The amount of M 23 C 6 was found to increase with decreased Ti content as shown in the Ti-motified 316 SS. In Nb-stabilized 347 SS, Nb(CN) precipitates were present in solution treated as well as annealed specimens. The M 23 C 6 precipitates were detected at an annealing temperature of 1050 0 C, which is higher than the precipitation temperature detected in 321 SS. Thermodynamic calculations were carried out to obtain the temperature where precipitation starts, and the temperatures where 50, 90 and 99% of the precipitates should be formed. The experimental results are in very good agreement with the calculations. (orig.) [de

  14. High cycle fatigue of austenitic stainless steels

    International Nuclear Information System (INIS)

    Gauthier, J.P.; Lehmann, D.; Picker

    1990-01-01

    This study concerns the evaluation of material data to be used in LMFBR design codes. High cycle fatigue properties of three austenitic stainless steels are evaluated: type AISI 316 (UKAEA tests), type AISI 316L (CEA tests) and type AISI 304 (Interatom tests). The data on these steels comprised some 550 data points from 14 casts. This data set covered a wide range of testing parameters: temperature from 20-625 0 C, frequency from 1-20 000 Hz, constant amplitude and random fatigue loading, with and without mean stress, etc. However, the testing conditions chosen by the three partners differed considerably because they had been fixed independently and not harmonized prior to the tests. This created considerable difficulties for the evaluations. Experimental procedures and statistical treatments used for the three subsets of data are described and discussed. Results are presented in tables and graphs. Although it is often difficult to single out the influence of each parameter due to the different testing conditions, several interesting conclusions can be drawn: The HCF properties of the three steels are consistent with the 0.2% proof stress, the fatigue limit being larger than the latter at temperatures above 550 0 C. The type 304 steel has lower tensile properties than the two other steels and hence also lower HCF properties. Parameters which clearly have a significant effect of HCF behaviour are mean stress or R-ratio (less in the non-endurance region than in the endurance region), temperature, cast or product. Other parameters have probably a weak or no effect but it is difficult to conclude due to insufficient data: environment, specimen orientation, frequency, specimen geometry

  15. Low stress creep of stainless steel

    International Nuclear Information System (INIS)

    Crossland, I.G.; Clay, B.D.; Baker, C.

    1976-06-01

    The creep of 20%Cr, 25%Ni, Nb stainless steel has been examined at temperatures from 675 to 775 0 C at sheer stressed below 13 MPa and grain sizes from 6 to 20μm. The results have indicated that the initial creep rates were linearly dependent upon stress but with a threshold stress below which no creep occurred, i.e. Bingham behaviour; in addition, the creep activation energy at small strains was substantially lower than the lattice self-diffusion value and the initial creep rates were approximately related to the grain size through an inverse cube relation. It has been concluded that at low strains (approaching the initial elastic deflection) the creep mechanism was probably that of grain boundary diffusion creep (Coble, 1963) and this is further supported by the close agreement between the observed and theoretically predicted creep rate values. Steady-state creep rates were not observed; initially the creep rates fell rapidly with strain after which a more gradual decrease occurred. Whilst the creep rate - stress relationship continued to be of a Bingham form, the progressive reduction in creep rate with strain was found to be mainly attributable to an increase in the effective viscosity, threshold stress effects being generally of secondary importance. A model has been proposed which explains the initial creep rates as being due to Cable creep with elastic accommodation at grain boundary particles. At higher strains grain boundary collapse caused by vacancy sinking is accommodated at precipitate particles by plastic deformation of the adjacent matrix material. (author)

  16. Corrosion-free precast prestressed concrete piles made with stainless steel reinforcement : construction, test and evaluation.

    Science.gov (United States)

    2015-03-01

    The use of duplex high-strength stainless steel (HSSS) grade 2205 prestressing strand and : austenitic stainless steel (SS) grade 304 spiral wire reinforcement is proposed as a replacement of : conventional prestressing steel, in order to provide a 1...

  17. 77 FR 60673 - Drawn Stainless Steel Sinks From the People's Republic of China: Antidumping Duty Investigation

    Science.gov (United States)

    2012-10-04

    ... without drain boards, whether finished or unfinished, regardless of type of finish, gauge, or grade of... the stainless steel, and then welding and finishing the vertical corners to form the bowls. Stainless...

  18. Evaluation of Additive Manufacturing for Stainless Steel Components

    Energy Technology Data Exchange (ETDEWEB)

    Peter, William H [ORNL; Lou, Xiaoyuan [General Electric (GE); List III, Frederick Alyious [ORNL; Webber, David [General Electric (GE)

    2016-09-01

    This collaboration between Oak Ridge National Laboratory and General Electric Company aimed to evaluate the mechanical properties, microstructure, and porosity of the additively manufactured 316L stainless steel by ORNL’s Renishaw AM250 machine for nuclear application. The program also evaluated the stress corrosion cracking and corrosion fatigue crack growth rate of the same material in high temperature water environments. Results show the properties of this material to be similar to the properties of 316L stainless steel fabricated additively with equipment from other manufacturers with slightly higher porosity. The stress corrosion crack growth rate is similar to that for wrought 316L stainless steel for an oxygenated high temperature water environment and slightly higher for a hydrogenated high temperature water environment. Optimized heat treatment of this material is expected to improve performance in high temperature water environments.

  19. Boron effect on stainless steel plasticity under hot deformation

    International Nuclear Information System (INIS)

    Bulat, S.I.; Kardonov, B.A.; Sorokina, N.A.

    1978-01-01

    The effect of boron on plasticity of stainless steels at temperatures of hot deformation has been studied at three levels of alloying, i.e. 0-0.01% (micro-alloying or modifying), 0.01-0.02% (low alloying) and 0.02-2.0% (high alloying). Introduction of 0.001-0.005% of boron increases hot plasticity of both low and high carbon stainless steels due to decrease in grain size and strengthening of grain boundaries. Microalloying by boron has a positive effect at temperatures below 1200-1220 deg C. At higher temperatures, particularly when its content exceeds 0.008%, boron deteriorates plasticity by increasing the size of grains and weakening their boundaries. 0.1-2% boron strengthen the stainless steel and dectease its plasticity

  20. Low-temperature creep of austenitic stainless steels

    Science.gov (United States)

    Reed, R. P.; Walsh, R. P.

    2017-09-01

    Plastic deformation under constant load (creep) in austenitic stainless steels has been measured at temperatures ranging from 4 K to room temperature. Low-temperature creep data taken from past and unreported austenitic stainless steel studies are analyzed and reviewed. Creep at cryogenic temperatures of common austenitic steels, such as AISI 304, 310 316, and nitrogen-strengthened steels, such as 304HN and 3116LN, are included. Analyses suggests that logarithmic creep (creep strain dependent on the log of test time) best describe austenitic stainless steel behavior in the secondary creep stage and that the slope of creep strain versus log time is dependent on the applied stress/yield strength ratio. The role of cold work, strain-induced martensitic transformations, and stacking fault energy on low-temperature creep behavior is discussed. The engineering significance of creep on cryogenic structures is discussed in terms of the total creep strain under constant load over their operational lifetime at allowable stress levels.

  1. Depth distribution of martensite in xenon implanted stainless steels

    International Nuclear Information System (INIS)

    Johansen, A.; Johnson, E.; Sarholt-Kristensen, L.; Steenstrup, S.; Hayashi, N.; Sakamoto, I.

    1989-01-01

    The amount of stress-induced martensite and its distribution in depth in xenon implanted austenitic stainless steel poly- and single crystals have been measured by Rutherford backscattering and channeling analysis, depth selective conversion electron Moessbauer spectroscopy, cross-sectional transmission electron microscopy and x-ray diffraction analysis. In low nickel 17/7, 304 and 316 commercial stainless steels and in 17:13 single crystals the martensitic transformation starts at the surface and develops towards greater depth with increasing xenon fluence. The implanted layer is nearly completely transformed, and the interface between martensite and austenite is rather sharp and well defined. In high nickel 310 commercial stainless steel and 15:19 and 20:19 single crystals, on the other hand, only insignificant amounts of martensite are observed. (orig.)

  2. Diffusionless bonding of aluminum to type 304 stainless steel

    International Nuclear Information System (INIS)

    Watson, R.D.

    1963-03-01

    High strength diffusionless bonds can be produced between 1S aluminum and oxidized 304 stainless steel by hot pressing and extrusion bonding. Both the hot pressing and extrusion bonding techniques have been developed to a point where consistently good bonds can be obtained. Although the bonding is performed at elevated temperatures (about 510 o C) a protective atmosphere is not required to produce strong bonds. The aluminum-stainless steel bonded specimens can be used to join aluminum and stainless steel by conventional welding. Welding close to the bond zone does not appear to affect the integrity of the bond. The extrusion bonding technique is covered by Canadian patent 702,438 January 26, 1965 and the hot press bonding technique by Canadian patent application 904,548 June 6, 1964. (author)

  3. Development of commercial nitrogen-rich stainless steels

    International Nuclear Information System (INIS)

    Liljas, M.

    1999-01-01

    This paper reviews the development of nitrogen alloyed stainless steels. Nitrogen alloying of austenitic stainless steels started at an early stage and was to a large extent caused by nickel shortage. However, direct technical advantages such as increased strength of the nitrogen alloyed steels made them attractive alternatives to the current steels. It was not until the advent of the AOD (argon oxygen decarburisation) process in the late 1960s that nitrogen alloying could be controlled to such accuracy that it became successful commercially on a broader scale. The paper describes production aspects and how nitrogen addition influences microstructure and the resulting properties of austenitic and duplex stainless steels. For austenitic steels there are several reasons for nitrogen alloying. Apart from increasing strength nitrogen also improves structural stability, work hardening and corrosion resistance. For duplex steels nitrogen also has a decisive effect in controlling the microstructure during thermal cycles such as welding. (orig.)

  4. Enhancement of Stainless Steel's Mechanical Properties via Carburizing Process

    Science.gov (United States)

    Ahmad, S.; Alias, S. K.; Abdullah, B.; Hafiz Mohd Bakri, Mohd.; Hafizuddin Jumadin, Muhammad; Mat Shah, Muhammad Amir

    2016-11-01

    Carburizing process is a method to disperse carbon into the steel surface in order to enhance its mechanical properties such as hardness and wear resistance. This paper study investigates the effect of carburizing temperature to the carbon dispersion layer in stainless steel. The standard AISI 304 stainless steel was carburized in two different temperatures which were 900°C and 950°C. The effect of carbon dispersion layers were observed and the results indicated that the increasing value of the average dispersion layer from 1.30 mm to 2.74 mm thickness was found to be related to increment of carburizing holding temperature . The increment of carbon thickness layer also resulted in improvement of hardness and tensile strength of carburized stainless steel.

  5. Corrosion in lithium-stainless steel thermal-convection systems

    International Nuclear Information System (INIS)

    Tortorelli, P.F.; DeVan, J.H.; Selle, J.E.

    1980-01-01

    The corrosion of types 304L and 316 austenitic stainless steel by flowing lithium was studied in thermal-convection loops operated at 500 to 650 0 C. Both weight and compositional changes were measured on specimens distributed throughout each loop and were combined with metallographic examinations to evaluate the corrosion processes. The corrosion rate and mass transfer characteristics did not significantly differ between the two austenitic stainless steels. Addition of 500 or 1700 wt ppM N to purified lithium did not increase the dissolution rate or change the attack mode of type 316 stainless steel. Adding 5 wt % Al to the lithium reduced the weight loss of this steel by a factor of 5 relative to a pure lithium-thermal-convection loop

  6. Systematic Review and Meta-Analysis of Intravesical Hyaluronic Acid and Hyaluronic Acid/Chondroitin Sulfate Instillation for Interstitial Cystitis/Painful Bladder Syndrome

    Directory of Open Access Journals (Sweden)

    Jung-Soo Pyo

    2016-09-01

    Full Text Available Background/Aims: To assess the efficacy of intravesical hyaluronic acid (HA and HA/chondroitin sulfate (CS instillation in patients with interstitial cystitis/painful bladder syndrome by systematic review and meta-analysis. Methods: A systematic literature search was performed using the keywords: ‘interstitial cystitis' or ‘painful bladder syndrome' or ‘bladder pain syndrome' and ‘hyaluronic acid', up to March 31, 2016. The primary outcome was visual analogue scale related pain symptom (VAS. Secondary outcomes were the O'Leary-Sant Interstitial Cystitis Symptom Index (ICSI and Problem Index (ICPI, frequency, nocturia, bladder volume, and voided urine volume. Results: Ten articles involving 390 patients were retrieved and assessed in analysis. A significant improvement in mean VAS on fixed-effect and random-effect models (mean difference [MD] -3.654, 95% confidence interval [CI] -3.814 to -3.495, and MD -3.206, 95% CI -4.156 to -2.257, respectively was found. Significant improvements were found in the ICSI (MD -3.223, 95% CI -4.132 to -2.315 and ICPI (MD -2.941, 95% CI -3.767 to -2.116. Similarly, the other outcomes were significantly improved. Conclusion: Intravesical HA and HA/CS instillation improved pain symptom, quality of life, and other outcomes and could be included as therapeutic modality of interstitial cystitis/painful bladder syndrome.

  7. Systematic Review and Meta-Analysis of Intravesical Hyaluronic Acid and Hyaluronic Acid/Chondroitin Sulfate Instillation for Interstitial Cystitis/Painful Bladder Syndrome.

    Science.gov (United States)

    Pyo, Jung-Soo; Cho, Won Jin

    2016-01-01

    To assess the efficacy of intravesical hyaluronic acid (HA) and HA/chondroitin sulfate (CS) instillation in patients with interstitial cystitis/painful bladder syndrome by systematic review and meta-analysis. A systematic literature search was performed using the keywords: 'interstitial cystitis' or 'painful bladder syndrome' or 'bladder pain syndrome' and 'hyaluronic acid', up to March 31, 2016. The primary outcome was visual analogue scale related pain symptom (VAS). Secondary outcomes were the O'Leary-Sant Interstitial Cystitis Symptom Index (ICSI) and Problem Index (ICPI), frequency, nocturia, bladder volume, and voided urine volume. Ten articles involving 390 patients were retrieved and assessed in analysis. A significant improvement in mean VAS on fixed-effect and random-effect models (mean difference [MD] -3.654, 95% confidence interval [CI] -3.814 to -3.495, and MD -3.206, 95% CI -4.156 to -2.257, respectively) was found. Significant improvements were found in the ICSI (MD -3.223, 95% CI -4.132 to -2.315) and ICPI (MD -2.941, 95% CI -3.767 to -2.116). Similarly, the other outcomes were significantly improved. Intravesical HA and HA/CS instillation improved pain symptom, quality of life, and other outcomes and could be included as therapeutic modality of interstitial cystitis/painful bladder syndrome. © 2016 The Author(s) Published by S. Karger AG, Basel.

  8. Instillation of Hyaluronic Acid via Electromotive Drug Administration Can Improve the Efficacy of Treatment in Patients With Interstitial Cystitis/Painful Bladder Syndrome: A Randomized Prospective Study.

    Science.gov (United States)

    Gülpınar, Omer; Haliloğlu, Ahmet Hakan; Gökce, Mehmet İlker; Arıkan, Nihat

    2014-05-01

    In the treatment of interstitial cystitis, intravesical hyaluronic acid application may be suggested as a treatment option. In this randomized prospective study, the authors aimed to identify whether instilling the hyaluronic acid with electromotive drug administration (EMDA) would increase the tissue uptake and improve the efficacy. The data of 31 patients who had been diagnosed with bladder pain syndrome/interstitial cystitis (BPS/IC) between 2004 and 2005 were examined. The patients were randomized to two groups: patients in group A received hyaluronic acid directly with a catheter and patients in group B received hyaluronic acid with EMDA. The patients were followed for 24 months and the two groups were compared at certain time intervals. The primary end points of the study were visual analogue scale (VAS) score, global response assessment, and micturition frequency in 24 hours. There were 6 males and 25 females. The two groups were similar in baseline parameters. The decrease in VAS score and the micturition frequency in 24 hours were significantly lower with EMDA at months 6 and 12. The difference between the two groups was not significant at months 1 and 24. Also, treatment with EMDA, positive KCl test, and pretreatment voiding frequency >17 were associated with higher response rates. Hyaluronic acid installation is an effective glycosaminoglycan substitution therapy in patients with BPS/IC. Instillation of hyaluronic acid via EMDA can improve the efficacy of the treatment; however, lack of long-term efficacy is the major problem with this glycosaminoglycan substitution therapy.

  9. Effect of nasal instillation of female urine or vaginal exudate on testosterone secretion in isolated and anesthetized male rhesus monkeys (Macaca mulatta).

    Science.gov (United States)

    Mora, O A; García Castiñeiras, S; Guisado, S; Ezquerra, C

    1990-01-01

    Two male adult rhesus monkeys were individually placed in cages with a pulling device in order to immobilize the animals for anesthesia. The room was temperature-controlled having a light/dark period of 12/12 hours. The animals were rapidly immobilized and immediately anesthetized with ketamine i. m. (10 mg/kg of body weight). They were bled four times at 15, 30, 45, and 60 mins after the ketamine injection, twice a week during 6 weeks. When necessary, maintenance doses of ketamine were administered. The levels of serum testosterone in experimental conditions (nasal instillation of female urine or a suspension of vaginal exudate) showed significant lower values with respect to those in control conditions (saline instillation). The control levels of testosterone tend to increase up to 60 mins. The testosterone from samples obtained in experimental conditions did not show such an increase, remaining similar during the sampling and similar to the 15 min control levels that could be considered as basal. These results seem to point out some chemical information from females capable of modifying the pattern of secretion of testosterone of the males in the above mentioned experimental conditions.

  10. Biomaterial Studies on AISI 316L Stainless Steel after Magnetoelectropolishing

    Science.gov (United States)

    Hryniewicz, Tadeusz; Rokosz, Krzysztof; Filippi, Massimiliano

    2009-01-01

    The polarisation characteristics of the electropolishing process in a magnetic field (MEP – magnetoelectropolishing), in comparison with those obtained under standard/conventional process (EP) conditions, have been obtained. The occurrence of an EP plateau has been observed in view of the optimization of MEP process. Up-to-date stainless steel surface studies always indicated some amount of free-metal atoms apart from the detected oxides and hydroxides. Such a morphology of the surface film usually affects the thermodynamic stability and corrosion resistance of surface oxide layer and is one of the most important features of stainless steels. With this new MEP process we can improve metal surface properties by making the stainless steel more resistant to halides encountered in a variety of environments. Furthermore, in this paper the stainless steel surface film study results have been presented. The results of the corrosion research carried out by the authors on the behaviour of the most commonly used material − medical grade AISI 316L stainless steel both in Ringer’s body fluid and in aqueous 3% NaCl solution have been investigated and presented earlier elsewhere, though some of these results, concerning the EIS Nyquist plots and polarization curves are also revealed herein. In this paper an attempt to explain this peculiar performance of 316L stainless steel has been undertaken. The SEM studies, Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS) were performed on 316L samples after three treatments: MP – abrasive polishing (800 grit size), EP – conventional electrolytic polishing, and MEP – magnetoelectropolishing. It has been found that the proposed magnetoelectropolishing (MEP) process considerably modifies the morphology and the composition of the surface film, thus leading to improved corrosion resistance of the studied 316L SS.

  11. Low temperature surface hardening of stainless steel; the role of plastic deformation

    DEFF Research Database (Denmark)

    Bottoli, Federico; Jespersen, Freja Nygaard; Hattel, Jesper Henri

    2016-01-01

    Thermochemical surface engineering by nitriding of austenitic stainless steel transforms the surface zone into expanded austenite, which improves the wear resistance of the stainless steel while preserving the stainless behavior. As a consequence of the thermochemical surface engineering, huge......: - plastic deformation of metastable austenitic stainless steels leads to the development of strain-induced martensite, which compromises the uniformity and the homogeneity of the expanded austenite zone. - during low temperature surface engineering composition and stress profiles develop. On numerical...

  12. Analysis of the Enameled AISI 316LVM Stainless Steel

    Science.gov (United States)

    Bukovec, Mitja; Xhanari, Klodian; Lešer, Tadej; Petovar, Barbara; Finšgar, Matjaž

    2018-03-01

    In this work, four different enamels were coated on AISI 316LVM stainless steel and the corrosion resistance of these samples was tested in 5 wt.% NaCl solution at room temperature. The preparation procedure of the enamels was optimized in terms of firing temperature, time and composition. First the thermal expansion was measured using dilatometry followed by electrochemical analysis using chronopotentiometry, electrochemical impedance spectroscopy and cyclic polarization. The topography of the most resistant sample was obtained by 3D-profilometry. All samples coated with enamel showed significantly higher corrosion and dilatation resistance compared with the uncoated stainless steel material.

  13. Corrosion behaviour of some conventional stainless steels in electrolyzing process

    Directory of Open Access Journals (Sweden)

    Amal NASSAR

    2015-12-01

    Full Text Available In this study, attempts were made to increase the amount of hydrogen generated from the water electrolysis process. Some conventional stainless steels (316; 409; 410 and 430 were used as anode and cathode in electrolysis process. Further study was carried out on the corrosion trend in all the investigated metals. It is observed that the electrode material can effect on the amount of hydrogen generate by electrolyzing process and metal composition of the stainless steels effects on the rate of corrosion.

  14. Analysis of the Enameled AISI 316LVM Stainless Steel

    Science.gov (United States)

    Bukovec, Mitja; Xhanari, Klodian; Lešer, Tadej; Petovar, Barbara; Finšgar, Matjaž

    2018-01-01

    In this work, four different enamels were coated on AISI 316LVM stainless steel and the corrosion resistance of these samples was tested in 5 wt.% NaCl solution at room temperature. The preparation procedure of the enamels was optimized in terms of firing temperature, time and composition. First the thermal expansion was measured using dilatometry followed by electrochemical analysis using chronopotentiometry, electrochemical impedance spectroscopy and cyclic polarization. The topography of the most resistant sample was obtained by 3D-profilometry. All samples coated with enamel showed significantly higher corrosion and dilatation resistance compared with the uncoated stainless steel material.

  15. Ozone decay on stainless steel and sugarcane bagasse surfaces

    Science.gov (United States)

    Souza-Corrêa, Jorge A.; Oliveira, Carlos; Amorim, Jayr

    2013-07-01

    Ozone was generated using dielectric barrier discharges at atmospheric pressure to treat sugarcane bagasse for bioethanol production. It was shown that interaction of ozone molecules with the pretreatment reactor wall (stainless steel) needs to be considered during bagasse oxidation in order to evaluate the pretreatment efficiency. The decomposition coefficients for ozone on both materials were determined to be (3.3 ± 0.2) × 10-8 for stainless steel and (2.0 ± 0.3) × 10-7 for bagasse. The results have indicated that ozone decomposition has occurred more efficiently on the biomass material.

  16. The use of titanium and stainless steel in fracture fixation.

    Science.gov (United States)

    Hayes, J S; Richards, R G

    2010-11-01

    The use of metal in fracture fixation has demonstrated unrivalled success for many years owing to its high stiffness, strength, biological toleration and overall reliable function. The most prominent materials used are electropolished stainless steel and commercially pure titanium, along with the more recent emergence of titanium alloys. Despite the many differences between electropolished stainless steel and titanium, both materials provide a relatively predictable clinical outcome, and offer similar success for fulfilling the main biomechanical and biological requirements of fracture fixation despite distinctive differences in implant properties and biological responses. This article explores these differences by highlighting the limitations and advantages of both materials, and addresses how this translates to clinical success.

  17. Resistance Element Welding of Magnesium Alloy/austenitic Stainless Steel

    Science.gov (United States)

    Manladan, S. M.; Yusof, F.; Ramesh, S.; Zhang, Y.; Luo, Z.; Ling, Z.

    2017-09-01

    Multi-material design is increasingly applied in the automotive and aerospace industries to reduce weight, improve crash-worthiness, and reduce environmental pollution. In the present study, a novel variant of resistance spot welding technique, known as resistance element welding was used to join AZ31 Mg alloy to 316 L austenitic stainless steel. The microstructure and mechanical properties of the joints were evaluated. It was found that the nugget consisted of two zones, including a peripheral fusion zone on the stainless steel side and the main fusion zone. The tensile shear properties of the joints are superior to those obtained by traditional resistance spot welding.

  18. Microstructural stability of 21-6-9 stainless steel

    International Nuclear Information System (INIS)

    Krenzer, R.W.; Sanderson, E.C.

    1978-01-01

    Two experiments were designed to better define parameters for thermomechanical processing of 21-6-9 stainless steel. This steel is one of the nitrogen-strengthened chromium, manganese, and nickel austenitic stainless steels having mechanical properties that can be improved by a combination of plastic deformation and heat treatments. By heat-treating coupons, the time-temperature relationship of the precipitate phase, and the solutionizing, recrystallizing, and stress-relieving temperature ranges in 21-6-9 were established. Secondly, mechanical properties and microstructure as a function of percent deformation and stress-relieving temperature are reported

  19. Failure of austenitic stainless steel tubes during steam generator operation

    OpenAIRE

    M. Głowacka; J. Łabanowski; S. Topolska

    2012-01-01

    Purpose: of this study is to analyze the causes of premature failure of steam generator coil made of austenitic stainless steel. Special attention is paid to corrosion damage processes within the welded joints.Design/methodology/approach: Examinations were conducted several segments of the coil made of seamless cold-formed pipes Ø 23x2.3 mm, of austenitic stainless steel grade X6CrNiTi18-10 according to EN 10088-1:2007. The working time of the device was 6 months. The reason for the withdrawa...

  20. Corrosion of 316L stainless steels MAVL wastes containers

    International Nuclear Information System (INIS)

    Helie, M.

    2003-01-01

    The long lived and medium activity wastes are conditioned or could be re-conditioned in primary drums of 316L stainless steels. In the framework of wastes storage, these drums will be placed in concrete containers; each containers would contain one or more drums. This document recalls global information on the corrosion of stainless steels, analyzes specific conditions bond to the drums conditioning in concrete containers and the nature of the wastes, and details the consequences on the possible risks of external and internal corrosion of the drums. (A.L.B.)

  1. Metal-ceramic interfaces: joining silicon nitride-stainless steel

    Science.gov (United States)

    Polanco, R.; De Pablos, A.; Miranzo, P.; Osendi, M. I.

    2004-11-01

    Joining of hot pressed silicon nitride using three types of stainless steel (AISI 304, 316 and 321) as interlayer was done by diffusion bonding at 1100 °C for 120 min. An extensive reaction zone of about 7 μm was formed in the contact region, where Cr2N, FexSiy and α-Fe were observed, outside that region the austenitic phase with precipitates of chromium nitride was observed. In the Mo-containing stainless steel (AISI 316) formation of Mo3Si was also detected. Moderate strengths were measured by shear testing for these joints.

  2. Stainless steel in contact with food and bevarage

    Directory of Open Access Journals (Sweden)

    Sveto Cvetkovski

    2012-12-01

    Full Text Available Stainless steels are probably the most important materials in the food and beverage industries. The main reason for such broad implementation of stainless steel in contact with food are excellent properties which they possess such as corrosion resistance, resistance to high and low temperatures, very good mechanical and physical properties, aesthetic appeal, inertness of surface, durability, easy cleaning and recycling. Low thermal conductivity of these steels produces steeper temperature coefficient provoking an increased distortion, shrinkage and stresses compared with carbon steel.

  3. Fatigue crack nucleation of type 316LN stainless steel

    International Nuclear Information System (INIS)

    Kim, Dae Whan; Kim, Woo Gon; Hong, Jun Hwa; Ryu, Woo Seog

    2000-01-01

    Low Cycle Fatigue (LCF) life decreases drastically with increasing temperature but increases with the addition of nitrogen at room and high temperatures. The effect of nitrogen on LCF life may be related to crack nucleation at high temperatures in austenitic stainless steel because the fraction of crack nucleation in LCF life is about 40%. The influence of nitrogen on the crack nucleation of LCF in type 316LN stainless steel is investigated by observations of crack population and crack depth after testing at 40% of fatigue life. Nitrogen increases the number of cycles to nucleate microcracks of 100 μm but decreases the crack population

  4. Intergranular stress corrosion in soldered joints of stainless steel 304

    International Nuclear Information System (INIS)

    Zamora R, L.

    1994-01-01

    The intergranular stress cracking of welded joints of austenitic stainless steel, AISI 304, is a serious problem in BWR type reactors. It is associated with the simultaneous presence of three factors; stress, a critical media and sensibilization (DOS). EPR technique was used in order to verify the sensibilization degree in the base metal, and the zone affected by heat and welding material. The characterization of material was done. The objective of this work is the study of microstructure and the evaluation of EPR technique used for the determination of DOS in a welded plate of austenitic stainless steel AISI 304. (Author)

  5. Pitting and stress corrosion cracking of stainless steel

    Science.gov (United States)

    Saithala, Janardhan R.

    An investigation has been performed to determine the pitting resistance of stainless steels and stress corrosion cracking of super duplex stainless steels in water containing chloride ions from 25 - 170°C. The steels studied are 12% Cr, FV520B, FV566, 304L, Uranus65, 2205, Ferallium Alloy 255, and Zeron 100. All these commercial materials used in very significant industrial applications and suffer from pitting and stress corrosion failures. The design of a new experimental setup using an autoclave enabled potentiodynamic polarisation experiments and slow strain rate tests in dilute environments to be conducted at elevated temperatures. The corrosion potentials were controlled using a three electrode cell with computer controlled potentiostat.The experimental programme to determine pitting potentials was designed to simulate the service conditions experienced in most industrial plants and develop mathematical model equations to help a design engineer in material selection decision. Stress corrosion resistance of recently developed Zeron100 was evaluated in dilute environments to propose a mechanism in chloride solutions at high' temperatures useful for the nuclear and power generation industry. Results have shown the significance of the composition of alloying elements across a wide range of stainless steels and its influence on pitting. Nitrogen and molybdenum added to modern duplex stainless steels was found to be unstable at higher temperatures. The fractographic results obtained using the scanning electron microscope (SEM) has given insight in the initiation of pitting in modem duplex and super duplex stainless steels. A mathematical model has been proposed to predict pitting in stainless steels based on the effect of environmental factors (temperature, chloride concentration, and chemical composition). An attempt has been made to identify the mechanism of SCC in Zeron100 super duplex stainless steel.The proposed empirical models have shown good correlation

  6. Topographical Anisotropy and Wetting of Ground Stainless Steel Surfaces

    Directory of Open Access Journals (Sweden)

    Cornelia Bellmann

    2012-12-01

    Full Text Available Microscopic and physico-chemical methods were used for a comprehensive surface characterization of different mechanically modified stainless steel surfaces. The surfaces were analyzed using high-resolution confocal microscopy, resulting in detailed information about the topographic properties. In addition, static water contact angle measurements were carried out to characterize the surface heterogeneity of the samples. The effect of morphological anisotropy on water contact angle anisotropy was investigated. The correlation between topography and wetting was studied by means of a model of wetting proposed in the present work, that allows quantifying the air volume of the interface water drop-stainless steel surface.

  7. 76 FR 1599 - Stainless Steel Bar From Brazil: Final Results of Antidumping Duty Administrative Review

    Science.gov (United States)

    2011-01-11

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-351-825] Stainless Steel Bar From... duty order on stainless steel bar from Brazil. The review covers one producer/exporter of the subject... its administrative review of the antidumping duty order on stainless steel bar (SSB) from Brazil. See...

  8. 77 FR 41969 - Stainless Steel Bar From Japan: Rescission of Antidumping Duty Administrative Review

    Science.gov (United States)

    2012-07-17

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-588-833] Stainless Steel Bar From... order on stainless steel bar from Japan (the Order) covering the period February 1, 2010, through... Suruga to the Secretary, ``Stainless Steel Bar--Withdrawal of Request for Administrative Review,'' dated...

  9. Modelling of composition and stress profiles in low temperature surface engineered stainless steel

    DEFF Research Database (Denmark)

    Jespersen, Freja Nygaard; Hattel, Jesper Henri; Somers, Marcel A. J.

    2015-01-01

    Thermochemical surface engineering by nitriding/carburizing of stainless steel causes a surface zone of expanded austenite, which improves the wear resistance of the stainless steel while preserving the stainless behavior. As a consequence of the thermochemical surface engineering, huge residual ...

  10. 76 FR 76437 - Certain Welded Stainless Steel Pipe From Korea and Taiwan

    Science.gov (United States)

    2011-12-07

    ... COMMISSION Certain Welded Stainless Steel Pipe From Korea and Taiwan Determination On the basis of the record... revocation of the antidumping duty orders on certain welded stainless steel pipe from Korea and Taiwan would... Publication 4280 (December 2011), entitled Certain Welded Stainless Steel Pipe from Korea and Taiwan...

  11. 75 FR 53714 - Stainless Steel Butt-Weld Pipe Fittings From Japan, Korea, and Taiwan

    Science.gov (United States)

    2010-09-01

    ... 564 (Third Review)] Stainless Steel Butt-Weld Pipe Fittings From Japan, Korea, and Taiwan AGENCY... antidumping duty orders on stainless steel butt-weld pipe fittings from Japan, Korea, and Taiwan. SUMMARY: The... stainless steel butt-weld pipe fittings from Japan, Korea, and Taiwan would be likely to lead to...

  12. Characterization of Stainless Steel Welding Fume Particles : Influence of Stainless Steel Grade, Welding Parameters and Particle Size

    OpenAIRE

    Mei, Nanxuan

    2016-01-01

    Welding is a widely used method to join two pieces of stainless steel. Since it produces a large amount of fume during the process, it can cause adverse health effects. The welding fume particles contain many elements. Among them Cr, Mn and Ni are of concern. These three elements can cause diseases if inhaled by humans, especially Cr(VI). In this project, welding fume particles are collected during welding of different stainless steel grades (austenitic AISI 304L and duplex LDX2101). Furtherm...

  13. Immobilization of mesoporous silica particles on stainless steel plates

    Energy Technology Data Exchange (ETDEWEB)

    Pasqua, Luigi, E-mail: luigi.pasqua@unical.it [University of Calabria, Department of Environmental and Chemical Engineering (Italy); Morra, Marco, E-mail: mmorra@nobilbio.com [Via Valcastellana 26 (Italy)

    2017-03-15

    A preliminary study aimed to the nano-engineering of stainless steel surface is presented. Aminopropyl-functionalized mesoporous silica is covalently and electrostatically anchored on the surface of stainless steel plates. The anchoring is carried out through the use of a nanometric spacer, and two different spacers are proposed (both below 2 nm in size). The first sample is obtained by anchoring to the stainless steel amino functionalized, a glutaryl dichloride spacer. This specie forms an amide linkage with the amino group while the unreacted acyl groups undergo hydrolysis giving a free carboxylic group. The so-obtained functionalized stainless steel plate is used as substrate for anchoring derivatized mesoporous silica particles. The second sample is prepared using 2-bromo-methyl propionic acid as spacer (BMPA). Successively, the carboxylic group of propionic acid is condensed to the aminopropyl derivatization on the external surface of the mesoporous silica particle through covalent bond. In both cases, a continuous deposition (coating thickness is around 10 μm) is obtained, in fact, XPS data do not reveal the metal elements constituting the plate. The nano-engineering of metal surfaces can represent an intriguing opportunity for producing long-term drug release or biomimetic surface.

  14. Lithium wetting of stainless steel for plasma facing components

    Science.gov (United States)

    Skinner, C. H.; Capece, A. M.; Roszell, J. P.; Koel, B. E.

    2014-10-01

    Ensuring continuous wetting of a solid container by the liquid metal is a critical issue in the design of liquid metal plasma facing components foreseen for NSTX-U and FNSF. Ultrathin wetting layers may form on metallic surfaces under ultrahigh vacuum (UHV) conditions if material reservoirs are present from which spreading and wetting can start. The combined scanning electron microscopy (SEM), Auger electron spectroscopy (AES) and ion beam etching capabilities of a Scanning Auger Microprobe (SAM) have been used to study the spreading of lithium films on stainless steel substrates. A small (mm-scale) amount of metallic lithium was applied to a stainless steel surface in an argon glove box and transferred to the SAM. Native impurities on the stainless steel and lithium surfaces were removed by Ar+ ion sputtering. Elemental mapping of Li and Li-O showed that surface diffusion of Li had taken place at room temperature, well below the 181°C Li melting temperature. The influence of temperature and surface oxidation on the rate of Li spreading on stainless steel will be reported. Support was provided through DOE Contract Number DE-AC02-09CH11466.

  15. Resistance microwelding of 316L stainless steel wire to block

    DEFF Research Database (Denmark)

    Friis, Kasper Storgaard; Khan, M.I.; Bay, Niels

    2011-01-01

    The excellent corrosion resistance of low carbon vacuum melted 316 stainless steel coupled with its non-magnetic properties makes it ideal for biomedical applications. The typical joint geometry for microcomponents, such as medical implants, includes joining of fine wire to a larger block. However...

  16. Design and construction of precast piles with stainless reinforcing steel.

    Science.gov (United States)

    2014-02-01

    The service life of prestressed concrete piles is, in part, dictated by the time required to corrode the steel once : chloride ions are at the surface of the steel. Stainless steel materials, although limited in availability in strand : form, have a ...

  17. Pitting corrosion protection of low nickel stainless steel by ...

    Indian Academy of Sciences (India)

    Pitting corrosion protection of low nickel stainless steel by electropolymerized conducting polymer coating in 0·5 M NaCl solution. T DHANABAL, G AMIRTHAGANESAN. ∗ and J RAVICHANDRAN. Post Graduate and Research Department of Chemistry, Sri Ramakrishna Mission Vidyalaya College of Arts and Science,.

  18. Quality control of stainless steel pipings for nuclear power generation

    International Nuclear Information System (INIS)

    Miki, Minoru; Kitamura, Ichiro; Ito, Hisao; Sasaki, Ryoichi

    1979-01-01

    The proportion of nuclear power in total power generation is increasing recently in order to avoid the concentrated dependence on petroleum resources, consequently the reliability of operation of nuclear power plants has become important. In order to improve the reliability of plants, the reliability of each machine or equipment must be improved, and for the purpose, the quality control at the time of manufacture is the important factor. The piping systems for BWRs are mostly made of carbon steel, and stainless steel pipings are used for the recirculation system cooling reactors and instrumentation system. Recently, grain boundary type stress corrosion cracking has occurred in the heat-affected zones of welded stainless steel pipings in some BWR plants. In this paper, the quality control of stainless steel pipings is described from the standpoint of preventing stress corrosion cracking in BWR plants. The pipings for nuclear power plants must have sufficient toughness so that the sudden rupture never occurs, and also sufficient corrosion resistance so that corrosion products do not raise the radioactivity level in reactors. The stress corrosion cracking occurred in SUS 304 pipings, the factors affecting the quality of stainless steel pipings, the working method which improves the corrosion resistance and welding control are explained. (Kako, I.)

  19. Analysis of polypyrrole-coated stainless steel electrodes ...

    Indian Academy of Sciences (India)

    WINTEC

    The galvanostatic polymerization of pyrrole is carried out on stainless steel electrodes using .... polymerization. Figure 3b indicates that the essential peaks anticipated for SS substrates are noticed. 3.2 Characterization of Ppy coated SS. In order to test the feasibility ..... Jesus Lopez-Palacios 2006 Polymer degradation and.

  20. Behavior of stainless steels in pressurized water reactor primary circuits

    International Nuclear Information System (INIS)

    Féron, D.; Herms, E.; Tanguy, B.

    2012-01-01

    Stainless steels are widely used in primary circuits of pressurized water reactors (PWRs). Operating experience with the various grades of stainless steels over several decades of years has generally been excellent. Nevertheless, stress corrosion failures have been reported in few cases. Two main factors contributing to SCC susceptibility enhancement are investigated in this study: cold work and irradiation. Irradiation is involved in the stress corrosion cracking and corrosion of in-core reactor components in PWR environment. Irradiated assisted stress corrosion cracking (IASCC) is a complex and multi-physics phenomenon for which a predictive modeling able to describe initiation and/or propagation is not yet achieved. Experimentally, development of initiation smart tests and of in situ instrumentation, also in nuclear reactors, is an important axis in order to gain a better understanding of IASCC kinetics. A strong susceptibility for SCC of heavily cold worked austenitic stainless steels is evidenced in hydrogenated primary water typical of PWRs. It is shown that for a given cold-working procedure, SCC susceptibility of austenitic stainless steels materials increases with increasing cold-work. Results have shown also strong influences of the cold work on the oxide layer composition and of the maximum stress on the time to fracture.

  1. Comparing creep in two stainless steels AISI 316

    International Nuclear Information System (INIS)

    Silveira, T.L. da; Monteiro, S.N.

    1976-07-01

    Two AISI 316 stainless steels, one of Brazilian fabrication (Villares), the other of foreign fabrication (Uddeholm) were submitted to creep tests with temperature ranging from 600 to 800 0 C. Some important differences in the mechanical behaviour of the two steels are pointed out. These differences are due to the particular thermomechanical history of the materials under consideration. (Author) [pt

  2. Integrated Computational Modelling of Thermochemical Surface Engineering of Stainless Steel

    DEFF Research Database (Denmark)

    Kücükyildiz, Ömer Can; Sonne, Mads Rostgaard; Thorborg, Jesper

    2017-01-01

    An implicit finite difference method (FDM) based numerical model for the prediction of composition- and stress-depth profiles developing during low temperature gas nitriding (LTGN) of 316 stainless steel is presented. The essential effects governing the kinetics of composition and coupled stress ...

  3. Monitoring of occupational exposure in manufacturing of stainless steel constructions

    Czech Academy of Sciences Publication Activity Database

    Kučera, Jan; Bencko, V.; Pápayová, A.; Šaligová, D.; Tejral, J.; Borská, L.

    2001-01-01

    Roč. 9, - (2001), s. 171-175 ISSN 1210-7778 R&D Projects: GA ČR GV202/97/K038 Institutional research plan: CEZ:AV0Z1048901 Keywords : occupational exposure * stainless steel construction industry * instrumental neutron activation analysis Subject RIV: FP - Other Medical Disciplines

  4. Chemical coloring on stainless steel by ultrasonic irradiation.

    Science.gov (United States)

    Cheng, Zuohui; Xue, Yongqiang; Ju, Hongbin

    2018-01-01

    To solve the problems of high temperature and non-uniformity of coloring on stainless steel, a new chemical coloring process, applying ultrasonic irradiation to the traditional chemical coloring process, was developed in this paper. The effects of ultrasonic frequency and power density (sound intensity) on chemical coloring on stainless steel were studied. The uniformity of morphology and colors was observed with the help of polarizing microscope and scanning electron microscopy (SEM), and the surface compositions were characterized by X-ray photoelectric spectroscopy (XPS), meanwhile, the wear resistance and the corrosion resistance were investigated, and the effect mechanism of ultrasonic irradiation on chemical coloring was discussed. These results show that in the process of chemical coloring on stainless steel by ultrasonic irradiation, the film composition is the same as the traditional chemical coloring, and this method can significantly enhance the uniformity, the wear and corrosion resistances of the color film and accelerate the coloring rate which makes the coloring temperature reduced to 40°C. The effects of ultrasonic irradiation on the chemical coloring can be attributed to the coloring rate accelerated and the coloring temperature reduced by thermal-effect, the uniformity of coloring film improved by dispersion-effect, and the wear and corrosion resistances of coloring film enhanced by cavitation-effect. Ultrasonic irradiation not only has an extensive application prospect for chemical coloring on stainless steel but also provides an valuable reference for other chemical coloring. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Pitting corrosion of low-Cr austenitic stainless steels

    International Nuclear Information System (INIS)

    Bullard, S.J.; Covino, B.S. Jr.

    1996-01-01

    The Albany Research Center has investigated the pitting corrosion resistance of experimental low-Cr stainless steels and several commercial stainless steels in chloride-containing aqueous and atmospheric environments. Previous research had shown the experimental alloys to be as corrosion resistant as commercial stainless steels in chloride-free acid environments. The alloys studied were Fe-8Cr-16Ni-5.5Si-1Cu-(0-1)Mo, 304 SS, and 316 SS. These alloys were examined by immersion and electrochemical tests in 3.5 wt. pct. NaCl and 6 wt.pct.FeCl 3 . Results of these tests showed that the addition of one weight percent Mo improved the pitting resistance of the low-Cr alloy and that the Mo-containing experimental alloy was as resistant to pitting as the commercial alloys. Electrochemical tests did, however, show the experimental alloys to be slightly less resistant to pitting than the commercial alloys. Because of these results, the low-Cr alloy with one weight percent Mo and 304 SS were exposed for one year to a marine atmospheric environment on the coast of Oregon. The marine atmospheric corrosion resistance of the low-Cr alloy was found to be comparable to that for type 304 stainless steel

  6. New Stainless Steel Alloys for Low Temperature Surface Hardening?

    DEFF Research Database (Denmark)

    Christiansen, Thomas Lundin; Dahl, Kristian Vinter; Somers, Marcel A. J.

    2015-01-01

    The present contribution showcases the possibility for developing new surface hardenable stainless steels containing strong nitride/carbide forming elements (SNCFE). Nitriding of the commercial alloys, austenitic A286, and ferritic AISI 409 illustrates the beneficial effect of having SNCFE present...

  7. Microstructural Characterization of Low Temperature Gas Nitrided Martensitic Stainless Steel

    DEFF Research Database (Denmark)

    Fernandes, Frederico Augusto Pires; Christiansen, Thomas Lundin; Somers, Marcel A. J.

    2015-01-01

    The present work presents microstructural investigations of the surface zone of low temperature gas nitrided precipitation hardening martensitic stainless steel AISI 630. Grazing incidence X-ray diffraction was applied to investigate the present phases after successive removal of very thin sections...

  8. Effect of Carvacrol on Salmonella Saintpaul Biofilms on Stainless ...

    African Journals Online (AJOL)

    environments, especially in the food processing industry. The surfaces of stainless steel equipment and utensils are known to be major sites of bacterial adhesion and biofilm formation and can consequently lead to food deterioration or food-borne disease transmission [2]. Several strategies for controlling bacterial adhesion ...

  9. Damage on 316LN stainless steel transformed by powder metallurgy

    International Nuclear Information System (INIS)

    Couturier, R.; Burlet, H.

    1998-01-01

    This study deals with the 316 LN stainless steel elaboration by powder metallurgy. This method allows the realization of structures in austenitic steel less affected by the thermal aging than the cast austenitic-ferritic components. The components are performed by the method of HIP (Hot Isostatic Pressing). Mechanical tests are provided to control mechanical properties

  10. Controlled dissolution of colossal quantities of nitrogen in stainless steel

    DEFF Research Database (Denmark)

    Christiansen, Thomas; Somers, Marcel A. J.

    2006-01-01

    The solubility of nitrogen in austenitic stainless steel was investigated thermogravimetrically by equilibrating thin foils of AISI 304 and AISI 316 in ammonia/hydrogen gas mixtures. Controlled dissolution of colossal amounts of nitrogen under metastable equilibrium conditions was realized, with ...

  11. Methane formation in tritium gas exposed to stainless steel

    International Nuclear Information System (INIS)

    Morris, G.A.

    1977-01-01

    Tests were performed to determine the effect cleanliness of a surface exposed to tritium gas had on methane formation. These tests performed on 304 stainless steel vessels, cleaned in various ways, showed that the methane formation was reduced by the use of various cleaning procedures

  12. Anomalous kinetics of lath martensite formation in stainless steel

    DEFF Research Database (Denmark)

    Villa, Matteo; Hansen, Mikkel Fougt; Pantleon, Karen

    2015-01-01

    The kinetics of lath martensite formation in Fe-17.3 wt-%Cr-7.1 wt-%Ni-1.1 wt-%Al-0.08 wt-%C stainless steel was investigated with magnetometry and microscopy. Lath martensite forms during cooling, heating and isothermally. For the first time, it is shown by magnetometry during extremely slow...

  13. No genotoxicity of a new nickel-free stainless steel.

    Science.gov (United States)

    Montanaro, L; Cervellati, M; Campoccia, D; Prati, C; Breschi, L; Arciola, C R

    2005-01-01

    Stainless steel is a metallic alloy largely employed in orthopedics, maxillofacial surgery and orthodontic therapy. However, the presence in its composition of a high quantity of nickel, an agent known to trigger toxic, allergic and cancerogenous responses in humans, is cause of some concern. In this study, we have investigated the in vitro mutagenicity and genotoxicity of a new nickel-free stainless steel, namely P558, in comparison to the conventional stainless steel AISI 316L. The cytogenetic effects were evaluated by studying the frequency of Sister Chromatid Exchanges (SCE) and chromosomal aberrations. Ames test was performed to detect the mutagenic activity. Both P558 and AISI 316L did not cause any significant increase in the average number of SCE and in chromosomal aberrations, either with or without metabolic activation. Furthermore, the Ames test showed that the extracts of both P558 and of AISI 316L are not mutagenic. Overall, these findings prove that P558 is devoid of genotoxicity and mutagenicity. The present results, together with other previous interesting observations that P558 promotes osseointegration, suggest that this new nickel-free stainless steel can represent a better alternative to other conventional steel alloys.

  14. Pitting corrosion protection of low nickel stainless steel by ...

    Indian Academy of Sciences (India)

    corrosive medium. The low value of Rct for uncoated speci- men is due to the easy penetration of the corrosive chloride ions through stainless steel surface. The double layer capacitance (Cdl) of PoPD decreases to a lower value than that of PANi and uncoated specimen, indi- cating the thickening of the PoPD polymer film.

  15. Effect of Carvacrol on Salmonella Saintpaul Biofilms on Stainless ...

    African Journals Online (AJOL)

    Purpose: To evaluate the effect of carvacrol against Salmonella Saintpaul biofilms on stainless steel surface. Methods: The effects of carvacrol on planktonic cells were evaluated by determining the minimum inhibitory concentration and minimal bactericidal concentration. The action of carvacrol on Salmonella Saintpaul ...

  16. Fatigue behavior of welded austenitic stainless steel in different environments

    Directory of Open Access Journals (Sweden)

    D.S. Yawas

    2014-01-01

    Full Text Available The fatigue behavior of welded austenitic stainless steel in 0.5 M hydrochloric acid and wet steam corrosive media has been investigated. The immersion time in the corrosive media was 30 days to simulate the effect on stainless steel structures/equipment in offshore and food processing applications and thereafter annealing heat treatment was carried out on the samples. The findings from the fatigue tests show that seawater specimens have a lower fatigue stress of 0.5 × 10−5 N/mm2 for the heat treated sample and 0.1 × 10−5 N/mm2 for the unheat-treated sample compared to the corresponding hydrochloric acid and steam samples. The post-welding heat treatment was found to increase the mechanical properties of the austenitic stainless steel especially tensile strength but it reduces the transformation and thermal stresses of the samples. These findings were further corroborated by the microstructural examination of the stainless steel specimen.

  17. Bending Behavior of Porous Sintered Stainless Steel Fiber Honeycombs

    Science.gov (United States)

    Zou, Shuiping; Wan, Zhenping; Lu, Longsheng; Tang, Yong

    2017-02-01

    A novel porous honeycomb-type substrate has been developed using solid-state sintering stainless steel fibers. The porous sintered stainless steel fiber honeycombs (PSSSFH) are composed of a skeleton of sintered stainless steel fibers, three-dimensionally interconnected porous structures and multiple parallel microchannels. The bending behavior of the PSSSFH is investigated using three-point bending tests. Four stages, including an elastic stage, a yielding stage with a plateau, a hardening stage and a failure stage, are observed during the bending process of the PSSSFH. In the initial yielding stage, the bending forces increase slowly with displacement increasing, and then a yielding plateau follows, which is unique compared with other porous materials. Moreover, the structure parameters of the PSSSFH are varied to investigate the influence on the bending strength. It is determined that the multiple parallel microchannels can enhance the bending strength of porous stainless steel fiber sintered substrates (PSSFSS) and do not influence the variation trend of bending strength of PSSFSS with porosity increasing. The open ratio is conducive to increasing the bending strength, and the microchannel diameters ranging from 0.5 mm to 1.5 mm have little influence on the bending strength. In addition, both the increasing of sintering temperature and sintering time can strengthen the PSSSFH.

  18. Bactericidal behavior of Cu-containing stainless steel surfaces

    Science.gov (United States)

    Zhang, Xiangyu; Huang, Xiaobo; Ma, Yong; Lin, Naiming; Fan, Ailan; Tang, Bin

    2012-10-01

    Stainless steels are one of the most common materials used in health care environments. However, the lack of antibacterial advantage has limited their use in practical application. In this paper, antibacterial stainless steel surfaces with different Cu contents have been prepared by plasma surface alloying technology (PSAT). The steel surface with Cu content 90 wt.% (Cu-SS) exhibits strong bactericidal activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) within 3 h. Although the Cu-containing surface with Cu content 2.5 wt.% (CuNi-SS) can also kill all tested bacteria, this process needs 12 h. SEM observation of the bacterial morphology and an agarose gel electrophoresis were performed to study the antibacterial mechanism of Cu-containing stainless steel surfaces against E. coli. The results indicated that Cu ions are released when the Cu-containing surfaces are in contact with bacterial and disrupt the cell membranes, killing the bacteria. The toxicity of Cu-alloyed surfaces does not cause damage to the bacterial DNA. These results provide a scientific explanation for the antimicrobial applications of Cu-containing stainless steel. The surfaces with different antibacterial abilities could be used as hygienic surfaces in healthcare-associated settings according to the diverse requirement of bactericidal activities.

  19. Laves intermetallics in stainless steel-zirconium alloys

    International Nuclear Information System (INIS)

    Abraham, D.P.; McDeavitt, S.M.; Richardson, J.W. Jr.

    1997-01-01

    Laves intermetallics have a significant effect on properties of metal waste forms being developed at Argonne National Laboratory. These waste forms are stainless steel-zirconium alloys that will contain radioactive metal isotopes isolated from spent nuclear fuel by electrometallurgical treatment. The baseline waste form composition for stainless steel-clad fuels is stainless steel-15 wt.% zirconium (SS-15Zr). This article presents results of neutron diffraction measurements, heat-treatment studies and mechanical testing on SS-15Zr alloys. The Laves intermetallics in these alloys, labeled Zr(Fe,Cr,Ni) 2+x , have both C36 and C15 crystal structures. A fraction of these intermetallics transform into (Fe,Cr,Ni) 23 Zr 6 during high-temperature annealing; the authors have proposed a mechanism for this transformation. The SS-15Zr alloys show virtually no elongation in uniaxial tension, but exhibit good strength and ductility in compression tests. This article also presents neutron diffraction and microstructural data for a stainless steel-42 wt.% zirconium (SS-42Zr) alloy

  20. Electroless nickel plating on stainless steels and aluminum

    Science.gov (United States)

    1966-01-01

    Procedures for applying an adherent electroless nickel plating on 303 SE, 304, and 17-7 PH stainless steels, and 7075 aluminum alloy was developed. When heat treated, the electroless nickel plating provides a hard surface coating on a high strength, corrosion resistant substrate.

  1. Analysis of polypyrrole-coated stainless steel electrodes

    Indian Academy of Sciences (India)

    The galvanostatic polymerization of pyrrole is carried out on stainless steel electrodes using -toluene sulphonic acid. The morphology of the film is studied from Scanning Electron Microscopy (SEM) measurements while the nature of the substrate is analysed using Energy Dispersive X-ray Spectroscopy (EDAX) technique.

  2. Static friction of stainless steel wire rope–rubber contacts.

    NARCIS (Netherlands)

    Loeve, A.J.; Krijger, T.; Mugge, W.; Breedveld, P.; Dodou, D.; Dankelman, J.

    2014-01-01

    Little is known about static friction of stainless-steel wire ropes ('cables') in contact with soft rubbers, an interface of potential importance for rigidifiable medical instruments. Although friction theories imply that the size and profile of the cables affect static friction, there are no

  3. Stress corrosion cracking of AISI 321 stainless steel in acidic ...

    Indian Academy of Sciences (India)

    Unknown

    seashore facilities showed that an acidic chloride solution film formed on the surface of steel and the stainless steel ... of the specimens was single phase auste- nite. After heat treatment, the specimens were pickled for .... metal at the crack tip reacted with the test solution to generate vacancies and the brittle fracture process ...

  4. Towards commercialization of fast gaseous nitrocarburising stainless steel

    DEFF Research Database (Denmark)

    Hummelshøj, Thomas Strabo; Christiansen, Thomas; Somers, Marcel A. J.

    2010-01-01

    A novel method for fast and versatile low temperature nitrocarburising of stainless steel has recently been invented by the present authors. Selected results obtained with this new surface hardening process are presented. It is shown that it is possible to obtain a case thickness of 20 μm...

  5. Assessment of Hot Crack Properties of Laser Welded Stainless Steel

    DEFF Research Database (Denmark)

    Juhl, Thomas Winther; Olsen, Flemming Ove

    2003-01-01

    Crack testing concerning small and fast solidifying laser welds in austenitic stainless steel has been studied. A set of methods has been applied to investigate alloy properties, including (1) Application of known information to predict solidification phases, (2) Weld metal solidification rate me...

  6. Properties of super stainless steels for orthodontic applications.

    Science.gov (United States)

    Oh, Keun-Taek; Kim, Young-Sik; Park, Yong-Soo; Kim, Kyoung-Nam

    2004-05-15

    Orthodontic stainless-steel appliances are considered to be corrosion resistant, but localized corrosion can occur in the oral cavity. This study was undertaken to evaluate the properties of super stainless steels in orthodontic applications. Accordingly, the metallurgical properties, mechanical properties, corrosion resistance, amount of the released nickel, cytotoxicity, and characteristics of the passive film were investigated. Corrosion resistances of the specimens were high and in the following order: super austenitic stainless steel (SR-50A) > super ferritic stainless steel (SFSS) = super duplex stainless steel (SR-6DX) > 316L SS > super martensitic stainless steel (SR-3Mo) in artificial saliva, 37 degrees C. At 500 mV (SCE), current densities of SR-50A, SFSS, SR-6DX, 316L SS, and SR-3Mo were 5.96 microA/cm(2), 20.3 microA/cm(2), 31.9 microA/cm(2), 805 microA/cm(2), and 5.36 mA/cm(2), respectively. Open circuit potentials of SR-50A, 316L SS, SR-6DX, SR-3Mo, and SFSS were - 0.2, - 0.22, - 0.24, - 0.43, and - 0.46 V (SCE), respectively. SR-50A, SFSS, and SR-6DX released below 3 ng/ml nickel for 8 weeks, and increased a little with immersion time, and 316L SS released about 3.5 ng/ml nickel, but SR-3Mo released a large amount of nickel, which increased with immersion time. The study demonstrated that SR-50A, SR-6DX, and SFSS have high corrosion resistance and mild or no cytotoxicity, due to the passive film enhanced by synergistic effect of Mo + N or by high addition effect of Cr + W. All super stainless steels showed very low cytotoxicity regardless of their nickel contents, although SR-3Mo was found to be relatively cytotoxic. From these studies, these steels are considered suitable for orthodontic applications. Copyright 2004 Wiley Periodicals, Inc.

  7. Thermal fatigue cracking of austenitic stainless steels

    International Nuclear Information System (INIS)

    Fissolo, A.

    2001-01-01

    This report deals with the thermal fatigue cracking of austenitic stainless steels as AISI 316 LN and 304 L. Such damage has been clearly observed for some components used in Fast Breeder reactors (FBR) and Pressure Water Reactor (PWR). In order to investigate thermal fatigue, quasi-structural specimen have been used. In this frame, facilities enforcing temperature variations similar to those found under the operation conditions have been progressively developed. As for components, loading results from impeded dilatation. In the SPLASH facility, the purpose was to establish accurate crack initiation conditions in order to check the relevance of the usual component design methodology. The tested specimen is continuously heated by the passage of an electrical DC current, and submitted to cyclic thermal down shock (up to 1000 deg C/s) by means of periodical spraying of water on two opposite specimen faces. The number of cycles to crack initiation N i is deduced from periodic examinations of the quenched surfaces, by means of optical microscopy. It is considered that initiation occurs when at least one 50μm to 150□m long crack is observed. Additional SPLASH tests were performed for N >> N i , with a view to investigate the evolution of a surface multiple cracking network with the number of cycles N. The CYTHIA test was mainly developed for the purpose of assessing crack growth dynamics of one isolated crack in thermal fatigue conditions. Specimens consist of thick walled tubes with a 1 mm circular groove is spark-machined at the specimen centre. During the test, the external wall of the tube is periodically heated by using a HF induction coil (1 MHz), while its internal wall is permanently cooled by flowing water. Total crack growth is derived from post-mortem examinations, whereby the thermal fatigue final rupture surface is oxidized at the end of the test. The specimen is broken afterwards under mechanical fatigue at room temperature. All the tests confirm that

  8. Management of the open abdomen using negative pressure wound therapy with instillation in severe abdominal sepsis: A review of 48 cases in Hospital Mexico, Costa Rica.

    Science.gov (United States)

    Sibaja, Pablo; Sanchez, Alfredo; Villegas, Guillermo; Apestegui, Alvaro; Mora, Esteban

    2017-01-01

    Despite the numerous advances in recent years, severe abdominal sepsis (with associated organ failure associated with infection) remains a serious, life-threatening condition with a high mortality rate. OA is a viable alternative to the previously used scheduled repeat laparotomy or continuous peritoneal lavage. The use of Negative Pressure Wound Therapy (NPWT) has been described as a successful method of management of the open abdomen. Adding instillation of saline solution to NPWT in a programmed and controlled manner, could offer the clinician an additional tool for the management of complex septic abdomen. To explore if the concept of active two-way therapy (Negative pressure wound therapy with instillation or NPWT-I) yields superior control of underlying, life-threatening abdominal infections and its effects on survival and morbidity in patients with severe abdominal sepsis when management with an open abdomen is required. A retrospective review of 48 patients with severe abdominal sepsis, who were managed with and open abdomen and NPWT-I was performed. NPWT-I was initiated utilizing the same parameters on all patients, this consisted of cycles of instillation of saline solution, which was removed through negative pressure after a short dwell period. We observed the effects on primary fascia closure rate, mortality, hospital and SICU length of stay and associated complications. Our patient group consisted of 20 (42%) males and 28 (58%) females. Average age was 48 years. Mortality in these patients was attributed to pulmonary embolism (n=1), acute renal failure (n=2) and cardiopulmonary arrest (n=1). Average total hospital stay was 24days, and stay in the SICU (n=26) averaged 7.5days. No acute complications related to the NPWT-I. All patients presenting with abdominal compartment syndrome resolved after initiation of the NPWT-I. A total of 46 patients (96%) patients achieved fascia closure after NPWT-I therapy after an average of 6days. Four patients (8%) died

  9. 75 FR 81966 - Top of the Stove Stainless Steel Cooking Ware From the Republic of Korea: Final Results of Sunset...

    Science.gov (United States)

    2010-12-29

    ... Stainless Steel Cooking Ware From the Republic of Korea: Final Results of Sunset Reviews and Revocation of... reviews of the antidumping and countervailing duty orders on top of the stove stainless steel cooking ware... the stove stainless steel cooking ware from Korea includes all non-electric cooking ware of stainless...

  10. Study to define NDE research for inspection of stainless steels

    International Nuclear Information System (INIS)

    Reinhart, E.R.

    1978-08-01

    After the boiling water reactor (BWR) stress corrosion cracking incidents on 4- and 10-inch stainless steel piping, the Electric Power Research Institute (EPRI) organized a round-robin ultrasonic examination of piping removed from service (TPS-75-609). Five inspection teams participated in this program, using both a standard procedure and the individual team procedure. The original intent was to section the piping after the program to evaluate the effectiveness of state-of-the-art ultrasonics in finding stress corrosion cracking. The sectioning was delayed, however, to allow research and development (R and D) groups time to perform basic measurements aimed at determining optimum search unit and instrument characteristics for the ultrasonic examination of stainless steel piping and to study the applicability of various advanced inspection methods. This additional effort was funded as part of an EPRI technical planning study (TPS-75-620), A Study to Define NDE Research for Inspection of Stainless Steels. Inspection methods evaluated in this study included (1) processing of manual scan data using a miniature programmable calculator (Aerojet Nuclear); (2) investigation into the performance characteristics of three experimental ultrasonic transducers (Battelle-Columbus Laboratories); (3) analysis of fundamental ultrasonic response data from intergranular stress corrosion cracks in stainless steels (Southwest Research Institute); and (4) a feasibility study of advanced signal processing and pattern recognition for analyzing flaws in stainless steel piping (Ultrasonics International). The results of the studies compiled in the report have indicated the direction for future research and development and have formed the basis for the recently initiated EPRI Research Project 892, Ultrasonic System Optimization

  11. A review of hot cracking in austenitic stainless steel weldments

    International Nuclear Information System (INIS)

    Shankar, V.; Gill, T.P.S.; Mannan, S.L.; Rodriguez, P.

    1991-01-01

    The occurrence of hot cracking in austenitic stainless steel weldments is discussed with respect to its origin and metallurgical contributory factors. Of the three types of hot cracking, namely solidification cracking, liquation and ductility dip cracking, solidification cracking occurs in the interdendritic regions in weld metal while liquation and ductility dip cracking occur intergranularly in the heat-affected zone (HAZ). Segregation of impurity and minor elements such as sulphur, phosphorous, silicon, niobium, boron etc to form low melting eutectic phases has been found to be the major cause of hot cracking. Control of HAZ cracking requires minimisation of impurity elements in the base metal. In stabilized stainless steels containing niobium, higher amounts of delta-ferrite have been found necessary to prevent cracking than in unstabilized compositions. Titanium compounds have been found to cause liquation cracking in maraging steels and titanium containing stainless steels and superalloys. In nitrogen added stainless steels, cracking resistance decreases when the solidification mode changes to primary austenitic due to nitrogen addition. A review of the test methods to evaluate hot cracking behaviour showed that several external restraint and semi-self-restraint tests are available. The finger Test, WRC Fissure Bend Test, the PVR test and the Varestraint Test are described along with typical test results. Hot ductility testing to reveal HAZ cracking tendency during welding is described, which is of particular importance to stabilized stainless steels. Based on the literature, recommendations are made for welding stabilized and nitrogen added steels, indicating areas of further work. (author). 81 refs., 30 figs., 1 tab

  12. Stress corrosion cracking (SCC) susceptibility of various stainless steels in oxygenated high temperature water

    International Nuclear Information System (INIS)

    Akashi, Masatsune; Kawamoto, Teruaki

    1978-01-01

    In order to evaluate new plant materials for their future applications to boiling water reactors (BWRs), the creviced bent beam SCC tests (CBB tests) were conducted on various sensitized stainless steels in oxygenated high temperature water. The results obtained are as follows. 1. Field SCC can be easily reproduced by the CBB test using the specimens taken from the 304 stainless steel pipe weld joints. 2. The SCC susceptibility of 18Cr-11Ni stainless steel in oxygenated high temperature water decreases markedly with the reduction of the carbon content. 3. The SCC susceptibility of low carbon stainless steels (304L, 316L) and stabilized stainless steels (321, 347) is significantly lower than that of the 304 and 316 stainless steels. 4. The addition of molybdenum causes the sensitization of stainless steels to delay at lower temperatures, improving the SCC resistance of the weld joints of BWR pipe materials. (auth.)

  13. DNA strand breaks, acute phase response and inflammation following pulmonary exposure by instillation to the diesel exhaust particle NIST1650b in mice

    DEFF Research Database (Denmark)

    Kyjovska, Zdenka O.; Jacobsen, Nicklas R.; Saber, Anne T.

    2015-01-01

    by the alkaline comet assay as DNA strand breaks in BAL cells, lung and liver tissue. The pulmonary acute phase response was analysed by Saa3 mRNA levels by real-time quantitative polymerase chain reaction. Instillation of DEP induced a strong neutrophil influx 1 and 3 days, but not 28 days post-exposure. Saa3 m......RNA levels were increased at all time point for the highest dose and 28 days post-exposure for the middle dose. DEP increased levels of DNA strand breaks in lung tissue for all doses 1 day post-exposure and after 28 days for mid- and high-dose groups. Pulmonary exposure to DEP induced transient inflammation...

  14. Albumin-binding of diclofenac and the effect of a site II inhibitor in the aqueous humor of cataract patients with the instillation of diclofenac.

    Science.gov (United States)

    Osaki, Takashi; Ozaki, Mineo; Takamura, Norito; Ogata, Kenji; Tokunaga, Jin; Setoguchi, Nao; Arimori, Kazuhiko

    2014-05-01

    Diclofenac instillation has been used widely in cataract surgery to prevent postoperative inflammation. Since diclofenac binds strongly to albumin in the circulation, it does not have a sufficient effect on patients in whom diclofenac binds strongly to albumin in the aqueous humor. A decrease in diclofenac binding and an increase in free diclofenac levels are necessary in these patients. The binding of diclofenac to albumin was investigated in the aqueous humor. In a diclofenac binding assay with albumin in the aqueous humor of individual patients, diclofenac was extracted from aliquots of the aqueous humor, and its total levels were measured using ultra high performance liquid chromatography (UHPLC). Free diclofenac levels were measured using ultrafiltration and UHPLC. The albumin-binding fraction of diclofenac was 0.8 or higher in the aqueous humor of some patients. Ibuprofen significantly inhibited diclofenac binding to site II of albumin in mimic aqueous humor, but not in pooled aqueous humor. This difference may have been due to the weak binding of diclofenac to site II in the pooled aqueous humor. Flurbiprofen was used instead of diclofenac. Flurbiprofen has been shown to bind more strongly than diclofenac to the same site of albumin. Thus, the inhibitory effect of ibuprofen on the binding of flurbiprofen to albumin was investigated in pooled aqueous humor. The results indicated that ibuprofen significantly inhibited the flurbiprofen binding. An effective diclofenac administration method may be established for clinical application by the instillation of an appropriate inhibitor of binding to the albumin site II. Copyright © 2014 John Wiley & Sons, Ltd.

  15. Low Temperature Surface Carburization of Stainless Steels

    Energy Technology Data Exchange (ETDEWEB)

    Collins, Sunniva R; Heuer, Arthur H; Sikka, Vinod K

    2007-12-07

    Low-temperature colossal supersaturation (LTCSS) is a novel surface hardening method for carburization of austenitic stainless steels (SS) without the precipitation of carbides. The formation of carbides is kinetically suppressed, enabling extremely high or colossal carbon supersaturation. As a result, surface carbon concentrations in excess of 12 at. % are routinely achieved. This treatment increases the surface hardness by a factor of four to five, improving resistance to wear, corrosion, and fatigue, with significant retained ductility. LTCSS is a diffusional surface hardening process that provides a uniform and conformal hardened gradient surface with no risk of delamination or peeling. The treatment retains the austenitic phase and is completely non-magnetic. In addition, because parts are treated at low temperature, they do not distort or change dimensions. During this treatment, carbon diffusion proceeds into the metal at temperatures that constrain substitutional diffusion or mobility between the metal alloy elements. Though immobilized and unable to assemble to form carbides, chromium and similar alloying elements nonetheless draw enormous amounts of carbon into their interstitial spaces. The carbon in the interstitial spaces of the alloy crystals makes the surface harder than ever achieved before by more conventional heat treating or diffusion process. The carbon solid solution manifests a Vickers hardness often exceeding 1000 HV (equivalent to 70 HRC). This project objective was to extend the LTCSS treatment to other austenitic alloys, and to quantify improvements in fatigue, corrosion, and wear resistance. Highlights from the research include the following: • Extension of the applicability of the LTCSS process to a broad range of austenitic and duplex grades of steels • Demonstration of LTCSS ability for a variety of different component shapes and sizes • Detailed microstructural characterization of LTCSS-treated samples of 316L and other alloys

  16. Accelerated corrosion of stainless steel in thiocyanate-containing solutions

    Energy Technology Data Exchange (ETDEWEB)

    Pistorius, P Chris; Li, Wen

    2012-09-19

    It is known that reduced sulfur compounds (such as thiocyanate and thiosulfate) can accelerate active corrosion of austenitic stainless steel in acid solutions, but before we started this project the mechanism of acceleration was largely unclear. This work combined electrochemical measurements and analysis using scanning electron microscopy (SEM) and X-ray photo-electron spectroscopy (XPS), which provided a comprehensive understanding of the catalytic effect of reduced sulfur species on the active corrosion of stainless steel. Both the behavior of the pure elements and the steel were studied and the work focused on the interaction between the pure elements of the steel, which is the least understood area. Upon completion of this work, several aspects are now much clearer. The main results from this work can be summarized as follows: The presence of low concentrations (around 0.1 mM) of thiocyanate or tetrathionate in dilute sulfuric acid greatly accelerates the anodic dissolution of chromium and nickel, but has an even stronger effect on stainless steels (iron-chromium-nickel alloys). Electrochemical measurements and surface analyses are in agreement with the suggestion that accelerated dissolution really results from suppressed passivation. Even well below the passivation potential, the electrochemical signature of passivation is evident in the electrode impedance; the electrode impedance shows clearly that this pre-passivation is suppressed in the presence of thiocyanate. For the stainless steels, remarkable changes in the morphology of the corroded metal surface and in the surface concentration of chromium support the suggestion that pre-passivation of stainless steels is suppressed because dissolution of chromium is accelerated. Surface analysis confirmed that adsorbed sulfur / sulfide forms on the metal surfaces upon exposure to solutions containing thiocyanate or thiosulfate. For pure nickel, and steels containing nickel (and residual copper), bulk sulfide

  17. Residual stresses and fatigue in a duplex stainless steel

    International Nuclear Information System (INIS)

    Johansson, Johan

    1999-01-01

    Duplex stainless steels, consisting of approximately equal amounts of austenite and ferrite, often combine the best features of austenitic and ferritic stainless steels. They generally have good mechanical properties, including high strength and ductility, and the corrosion resistance is often better than conventional austenitic grades. This has lead to a growing use of duplex stainless steels as a material in mechanically loaded constructions. However, detailed knowledge regarding its mechanical properties and deformation mechanisms are still lacking. In this thesis special emphasis has been placed on the residual stresses and their influence on mechanical behaviour of duplex stainless steels. Due to the difference in coefficient of thermal expansion between the two phases, tensile microstresses are found in the austenitic phase and balancing compressive microstresses in the ferritic phase. The first part of this thesis is a literature survey, which will give an introduction to duplex stainless steels and review the fatigue properties of duplex stainless steels and the influence of residual stresses in two-phase material. The second part concerns the evolution of the residual stress state during uniaxial loading. Initial residual stresses were found to be almost two times higher in the transverse direction compared to the rolling direction. During loading the absolute value of the microstresses increased in the macroscopic elastic regime but started to decrease with increasing load in the macroscopic plastic regime. A significant increase of the microstresses was also found to occur during unloading. Finite element simulations also show stress variation within one phase and a strong influence of both the elastic and plastic anisotropy of the individual phases on the simulated stress state. In the third part, the load sharing between the phases during cyclic loading is studied. X-ray diffraction stress analysis and transmission electron microscopy show that even if

  18. Residual stresses and fatigue in a duplex stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, Johan

    1999-05-01

    Duplex stainless steels, consisting of approximately equal amounts of austenite and ferrite, often combine the best features of austenitic and ferritic stainless steels. They generally have good mechanical properties, including high strength and ductility, and the corrosion resistance is often better than conventional austenitic grades. This has lead to a growing use of duplex stainless steels as a material in mechanically loaded constructions. However, detailed knowledge regarding its mechanical properties and deformation mechanisms are still lacking. In this thesis special emphasis has been placed on the residual stresses and their influence on mechanical behaviour of duplex stainless steels. Due to the difference in coefficient of thermal expansion between the two phases, tensile microstresses are found in the austenitic phase and balancing compressive microstresses in the ferritic phase. The first part of this thesis is a literature survey, which will give an introduction to duplex stainless steels and review the fatigue properties of duplex stainless steels and the influence of residual stresses in two-phase material. The second part concerns the evolution of the residual stress state during uniaxial loading. Initial residual stresses were found to be almost two times higher in the transverse direction compared to the rolling direction. During loading the absolute value of the microstresses increased in the macroscopic elastic regime but started to decrease with increasing load in the macroscopic plastic regime. A significant increase of the microstresses was also found to occur during unloading. Finite element simulations also show stress variation within one phase and a strong influence of both the elastic and plastic anisotropy of the individual phases on the simulated stress state. In the third part, the load sharing between the phases during cyclic loading is studied. X-ray diffraction stress analysis and transmission electron microscopy show that even if

  19. Efficacy and safety of 0.75% ropivacaine instillation into subinguinal wound in patients after bilateral microsurgical varicocelectomy: a bi-center, randomized, double-blind, placebo-controlled trial

    Directory of Open Access Journals (Sweden)

    Cui WS

    2017-07-01

    Full Text Available Wan Shou Cui,1,* Yu Seob Shin,2,3,* Jae Hyung You,3 A Ram Doo,4 Kiran Kumar Soni,3 Jong Kwan Park3 1Andrology Center, Peking University First Hospital, Beijing, People’s Republic of China; 2Department of Urology, Armed Forces Capital Hospital, Seongnam, 3Department of Urology, Chonbuk National University and Research Institute of Clinical Medicine of Chonbuk National University-Biomedical Research Institute and Medical Device Clinical Trial Center of Chonbuk National University Hospital, Jeonju, 4Department of Anesthesiology and Pain Medicine, Chonbuk National University Medical School, Jeonju, Republic of Korea *These authors contributed equally to this work Objective: To evaluate the efficacy and safety of 0.75% ropivacaine instillation into inguinal wound in patients who have undergone bilateral microsurgical varicocelectomy.Patients and methods: Eighty-five men who were screened for bilateral varicoceles from March 2015 to July 2016 were randomized for the treatment. All patients underwent inguinal varicocelectomy by general anesthesia. After ligation of the internal spermatic veins from the spermatic cord, additional delivery of testis through inguinal incision site was done to ligate external spermatic veins and gubernacular veins. Before repairing external oblique aponeurosis, 6 mL of 0.75% ropivacaine and 6 mL of normal saline were instilled under the fascia and around the funiculus (spermatic cord by a randomized and double-blind method. Visual analog scale (VAS pain score and Prince Henry Pain Score (PHPS were used for evaluating operative sites at 1, 2, 4, and 8 hours and 7 days after surgery. Safety and tolerability were evaluated throughout the course of this study by assessing adverse events.Results: A total of 55 men completed the study. Of these 55 men, 31 received instillation of ropivacaine on the left operative site, while 24 received instillation of ropivacaine on the right operative site. VAS pain scores and PHPS in

  20. In vivo fluorescence imaging of an orthotopic rat bladder tumor model indicates differential uptake of intravesically instilled near-infrared labeled 2-deoxyglucose analog by neoplastic urinary bladder tissues

    Science.gov (United States)

    Piao, Daqing; Davis, Carole A.; Hurst, Robert E.; Slaton, Joel W.

    2017-02-01

    Bladder cancer is one of the most expensive cancers to manage due to frequent recurrences requiring life-long surveillance and treatment. A near-infrared labeled 2-deoxy-d-glucose probe IRDye800CW-DG targeting glucose metabolism pathway has shown to enhance the sensitivity of diagnosing several types of cancers as tested on tumor models not including bladder tumor. This pilot study has explored differential uptake of intravesically administered IRDye800CW-DG in an orthotopic rat bladder tumor model. Twenty-five female Fischer rats were randomly grouped to four conditions: no-tumor-control (n=3), no-tumor-control intravesically instilled with IRDye800CWDG (n=6), rats bearing GFP-labeled AY-27 rat bladder urothelial cell carcinoma cells and washed with saline (n=5), and rats bearing AY-27 tumors and intravesically instilled with IRDye800CW-DG (n=11). Near-infrared fluorescence was measured from the opened bladder wall of anesthetized rat at an excitation wavelength of 750nm and an emission wavelength of 776nm, by using an in-house fluorescence imaging system. There is no statistically significant difference of the peak fluorescence intensity among the no-tumor-control bladders (n=3), the no-tumorcontrol bladders instilled with IRDye800CW-DG (n=6), and the GFP-labeled AY-27 treated bladders washed by saline (n=5). When compared to that of the no-tumor-control bladders instilled with IRDye800CW-DG (n=6), the fluorescence intensity of GFP-labeled AY-27 treated bladders instilled with IRDye800CW-DG and with histology confirmed neoplastic bladder tissue (n=11) was remarkably more intense (3.34 fold of over the former) and was also statistically significant (pbladder tissues suggests the potential for cystoscopy-adaptation to enhance diagnosis and guiding surgical management of flat urinary bladder cancer.

  1. Internal microporosity formation in stainless steel powders: kinetics and mechanism

    International Nuclear Information System (INIS)

    Martinez, M.; Suwardijo, W.; Garcia, L.; Formoso, A.; Cores, A.

    2002-01-01

    The internal microporosity of stainless steel powders is obtained by a technology developed in the Metallurgical Research Center (CIME) in collaboration with ISPETP, which consists of carbon enrichment of alloy during the fusion process, and after powder atomization a subsequent decarburization annealing. The internal microporosity , which can reach up to 10 volume percent of the steel particle, reduces powder density and improves powder compressibility, while costs for technology installation are also reduced. In this paper the technology for obtaining the microporosity, the mathematical models of the process, and the structural transformations undergone by stainless steel powder are shown. It is concluded that for carbon contents lower than 0.05% internal microporosity tends to disappear. (Author) 17 refs

  2. Infrared electro-thermal NDE of stainless steel

    International Nuclear Information System (INIS)

    Green, D.R.; Hassberger, J.A.

    1975-01-01

    Electro-thermal examination, a branch of thermal testing, is a promising method being developed for nondestructive examination of stainless steel welds. This paper describes the first phase of development; i.e., preliminary demonstration and laboratory evaluation of the method's sensitivity to notches in Type 304 stainless steel plate specimens. It also includes a description of the basic principles, together with a description of the hardware and experimental results showing that electrical discharge machined notches down to 0.16 cm long x 0.08 cm deep were detected. A qualitative technique for interpreting the test results to determine whether defects are at the surface or deeper within the material is demonstrated

  3. Aging degradation of cast stainless steel: status and program

    International Nuclear Information System (INIS)

    Chopra, O.K.; Ayrault, G.

    1983-10-01

    A program has been initiated to investigate the significance of in-service embrittlement of cast duplex stainless steels under light-water reactor operating conditions. The existing data are reviewed to determine the critical parameters that control the aging behavior and to define the objectives and scope of the investigation. The test matrices for microstructural studies and mechanical property measurements are presented. The initial experimental effort is focussed on characterizing the microstructure of long-term, low-temperature aged material. Specimens from three heats of cast CF-8 and CF-8M stainless steel aged for up to 70,000 h at 300, 350, and 400 0 C were obtained from George Fisher Ltd., of Switzerland. Initial analyses reveal the formation of three different types of precipitates which are not α'. An FCC phase, similar to the M 23 C 6 precipitates, was present in all the long-term aged material. 15 references, 10 figures, 2 tables

  4. PITTING CORROSION OF STAINLESS STEEL AT THE VARIOUS SURFACE TREATMENT

    Directory of Open Access Journals (Sweden)

    Viera Zatkalíková

    2011-09-01

    Full Text Available The stainless steel surface treatment is very important with regard to its pitting corrosion susceptibility. An effect of various types surfacing on pitting corrosion resistance of AISI 304stainless steel is investigated in this work. The samples of the tested material are turned, blasted, peened, grinded and a half of them are pickled to achieve higher purity of surfaces and better quality of passive film. Eight types of different finished surfaces are tested by electrochemical and immersion tests to determine corrosion behaviour in conditions where pitting is evoked by controlled potential and second by solution with high redox potential. By this way the effect of mechanical and chemical surface treatment on the resistance to pitting corrosion, character, size and shape of pits are compared in the conditions of different mechanisms of corrosion process.

  5. Inorganic coatings on stainless steel for protection against crevice corrosion

    International Nuclear Information System (INIS)

    Henrikson, Sture

    1989-12-01

    In order to create protection against crevice corrosion stainless steel test specimens of type 316 steel with various inorganic coatings applied on crevice surfaces were tested for 3-50 months at 25 and 30 degree C in natural seawater containing 0.2-1.5 ppm free chlorine. Various metallic coatings, Ni base alloys with Cr and Mo, Ni with W, pure Ag and pure Mo, as well as ceramic coatings - Cr 2 O 3 , TiO 2 and Al 2 O 3 - were studied. All the coatings tested, except pure Molybdenum applied by plasma spraying in a max 0.1 mm thick layer were found to promote crevice corrosion of the stainless steel. A significant reduction of the crevice corrosion susceptibility was obtained with Molybdenum. The result is considered promising enough to justify full scale tests in seawater on flange joints of pipes, valves or pumps. (author)

  6. Hydrogen transport through stainless steel under plasma irradiation

    Science.gov (United States)

    Airapetov, A. A.; Begrambekov, L. B.; Kaplevsky, A. S.; Sadovskiy, Ya A.

    2016-01-01

    The paper presents the results of investigation of gas exchange through stainless steel surface of the plasma chamber under irradiation with hydrogen atoms in oxygen atmosphere or oxygen contaminated hydrogen plasma. Dependence of this process on various irradiation parameters, such as the metal temperature, energy of irradiating ions, gas composition of plasma are studied. It is shown, that desorption from stainless steel is activated with the increase of the plasma chamber walls temperature and energy of irradiating ions. Hydrogen release occurs also under irradiation of the walls by helium and argon plasmas added with oxygen, however the amount of released hydrogen is several times lower than in the case of irradiation with oxygen contaminated deuterium plasma.

  7. Liquid Phase Sintering of Highly Alloyed Stainless Steel

    DEFF Research Database (Denmark)

    Mathiesen, Troels

    1996-01-01

    of boride to AISI 316L type steels have previously been studied, but were found to be sensitive to intergranular corrosion due to formation of intermetallic phases rich in chromium and molybdenum. In order to improve this system further, new investigations have focused on the use of higher alloyed stainless......Liquid phase sintering of stainless steel is usually applied to improve corrosion resistance by obtaining a material without an open pore system. The dense structure normally also give a higher strength when compared to conventional sintered steel. Liquid phase sintrering based on addition...... calculations, made by use of the computer programme Thermo-Calc, were also correlated with the observed microstructure. Corrosion measurements by electrochemical techniques show no signs of intergranular corrosion in contrast to the case of AISI 316L based steel. Furthermore most of the material showed...

  8. Multilayer modelling of stainless steel with a nanocrystallised superficial layer

    Energy Technology Data Exchange (ETDEWEB)

    Petit, J. [Laboratoire Energetique Mecanique Electromagnetisme (LEME), EA4416, Universite Paris Ouest, 92410 Ville d' Avray (France); Waltz, L., E-mail: laurent.waltz@univ-montp2.fr [Laboratoire de Mecanique et Genie Civil de Montpellier (LMGC), University of Montpellier II, Place Eugene Bataillon, 34000 Montpellier (France); Montay, G.; Retraint, D.; Roos, A.; Francois, M. [Institut Charles Delaunay - LASMIS, UMR CNRS 6279, University of Technology of Troyes, 10010 Troyes (France)

    2012-02-28

    Highlights: Black-Right-Pointing-Pointer SMAT has been used for nanocrystallisation of an austenitic stainless steel. Black-Right-Pointing-Pointer The mechanical response of the nano-phase has been obtained by an indirect method. Black-Right-Pointing-Pointer Minimisation of a stress formulated objective function. Black-Right-Pointing-Pointer The model predicts the strain at which diffuse necking occurs. - Abstract: In order to obtain the macroscopic mechanical response of a 316L stainless steel, nanocrystallised by Surface Mechanical Attrition Treatment (SMAT), a multilayer model is proposed. The constitutive behaviour of each layer is determined from tensile tests or by an inverse method and its thickness is evaluated from Scanning and Transmission Electron Microscopy (SEM and TEM) analyses and local hardness measurements. The consistency of the model is verified by its ability to predict the strain at which diffuse necking occurs.

  9. Failure Assessment of Stainless Steel and Titanium Brazed Joints

    Science.gov (United States)

    Flom, Yury A.

    2012-01-01

    Following successful application of Coulomb-Mohr and interaction equations for evaluation of safety margins in Albemet 162 brazed joints, two additional base metal/filler metal systems were investigated. Specimens consisting of stainless steel brazed with silver-base filler metal and titanium brazed with 1100 Al alloy were tested to failure under combined action of tensile, shear, bending and torsion loads. Finite Element Analysis (FEA), hand calculations and digital image comparison (DIC) techniques were used to estimate failure stresses and construct Failure Assessment Diagrams (FAD). This study confirms that interaction equation R(sub sigma) + R(sub tau) = 1, where R(sub sigma) and R(sub t u) are normal and shear stress ratios, can be used as conservative lower bound estimate of the failure criterion in stainless steel and titanium brazed joints.

  10. Magnetic properties of the austenitic stainless steels at cryogenic temperatures

    International Nuclear Information System (INIS)

    Kobayashi, T.; Tsuchiya, K.; Itoh, K.; Kobayashi, S.

    2002-01-01

    The magnetization was measured for the austenitic stainless steel of SUS304, SUS304L, SUS316, and SUS316L with the temperature from 5K to 300K and the magnetic field from 0T to 10T. The field dependences of the magnetizations changed at about 0.7T and 4T. The dependence was analyzed with ranges of 0-0.5T, 1-3T, and 5-10T. There was not so much difference between those stainless steels for the usage at small fields and 300 K. The SUS316 and SUS316L samples showed large non-linearity at high fields and 5K. Therefore, SUS304 was recommended for usage at high fields and low temperatures to design superconducting magnets with the linear approximation of the field dependence of magnetization

  11. Laser composite surfacing of stainless steel with SiC

    Science.gov (United States)

    Dutta Majumdar, J.; Chandra, B. Ramesh; Nath, A. K.; Manna, I.

    2006-07-01

    In the present study, an attempt has been made to improve wear resistance of AISI 304 stainless steel by laser composite surfacing with SiC. Laser processing has been carried out by pre-deposition of Fe + SiC powders (in the ratio of 85:15 and thickness of 100 m) on AISI 304 stainless steel substrate and subsequently, melting it using a 2 kW continuous wave CO2 laser. Following laser processing, a detailed characterization and evaluation of mechanical/electrochemical properties of the composite layer were undertaken to study the influence of laser processing on the characteristics and properties of the composite layer. Microstructure of the composite layer consisted of uniformly dispersed SiC particles in grain refined -Fe dendrites. Laser composite surfacing led to a significant improvement in microhardness and wear resistance as compared to as-received substrate. However, pitting corrosion property was marginally deteriorated due to laser composite surfacing.

  12. Robustness of steel joints with stainless steel bolts in fire

    Science.gov (United States)

    Satheeskumar, N.; Davison, J. B.

    2014-12-01

    The robustness of steel joints in fire is important for steel building structures because of the need to prevent progressive collapse. Stainless steel is widely used in building construction mainly because of its corrosion resistance, but it also possesses improved fire resistance compared with conventional non-alloy, fine grain structural steels. Extensive research performed on the robustness of steel joints in fire has revealed that failure at elevated temperature may be controlled by bolt shear for fin plate and web cleat connections. Hence, this study focussed on the use of stainless steel in experimental tests conducted on fin plate and web cleat connections at high temperatures. In addition, this study investigated the use of a component-based model to predict connection performance at elevated temperature.

  13. Finite Element Modelling of Cold Formed Stainless Steel Columns

    Directory of Open Access Journals (Sweden)

    M. Macdonald

    2005-01-01

    Full Text Available This paper describes the results obtained from a finite element investigation into the load capacity of column members of lipped channel cross-section, cold formed from Type 304 stainless steel, subjected to concentric and eccentric compression loading. The main aims of this investigation were to determine the effects which the non-linearity of the stress-strain behaviour of the material would have on the column behaviour under concentric or eccentric loading. Stress-strain curves derived from tests and design codes are incorporated into non-linear finite element analyses of eccentrically loaded columns and the results obtained are compared with those obtained on the basis of experiments on stainless steel channel columns with the same properties and dimensions. Comparisons of the finite element results and the test results are also made with existing design specifications and conclusions are drawn on the basis of the comparisons. 

  14. Stainless steel valves with enhanced performance through microstructure optimization

    Science.gov (United States)

    Barani, A. A.; Boukhattam, M.; Haggeney, M.; Güler, S.

    2017-08-01

    Compressor valves are made of hardened and tempered martensitic steels. The main design criterion for the material selection is the fatigue performance of the material under bending loads. In some cases impact loads and corrosive atmospheres additionally act on the part. For the first time, the microstructure of the most commonly used stainless steel and its influence on the properties relevant for flapper valves is presented and described in this paper. It is demonstrated how the tensile properties of a martensitic stainless steel can be enhanced by tailoring the microstructure. Electron back scatter diffraction method is carried out to explain the changes in monotonic mechanical properties. Through a modified heat treatment the martensite microstructure is refined resulting in an increase of yield and ultimate tensile strength and at the same time a significant increase of elongation.

  15. SCC-induced failure of a 304 stainless steel pipe

    International Nuclear Information System (INIS)

    Tapping, R.L.; Disney, D.J.; Szostak, F.J.

    1993-01-01

    On 1991 January 12, a 304 Stainless Steel (SS) suction line in the AECL-Research NRU reactor failed, shutting down the reactor for approximately 12 months. The pipe, a 32 mm schedule 40 304 stainless steel line exposed to D 2 O at temperatures ≤35 degrees C had been in service for approximately 20 years, although no manufacturing data or composition specifications were available. The failure and resultant leak resulted in a small loss of D 2 O moderator from the reactor vessel. The pipe cracked approximately 180 degrees C around the circumference of a weld. This failure was unexpected and hense a thorough metallographic examination was carried out on the failed section, on the rest of the line (Line 1212), and on representative samples from the rest of the reactor in order to assess the integrity of the remaining piping

  16. Microstructural and Mechanical Characterization of Solidified Austenitic Stainless Steels

    Directory of Open Access Journals (Sweden)

    Aktaş Çelik G.

    2017-09-01

    Full Text Available Among the family of stainless steels, cast austenitic stainless steels (CASSs are preferably used due to their high mechanical properties and corrosion resistance. These steels owe their properties to their microstructural features consisting of an austenitic matrix and skeletal or lathy type δ-ferrite depending on the cooling rate. In this study, the solidification behavior of CASSs (304L and 316L grades was studied using ThermoCalc software in order to determine the solidification sequence and final microstructure during cooling. Theoretical findings were supported by the microstructural examinations. For the mechanical characterization, not only hardness measurements but also tribological studies were carried out under dry sliding conditions and worn surfaces were examined by microscopy and 3D profilometric analysis. Results were discussed according to the type and amount of microstructural features.

  17. Investigation of Laser Peening Effects on Hydrogen Charged Stainless Steels

    Energy Technology Data Exchange (ETDEWEB)

    Zaleski, Tania M. [San Jose State Univ., CA (United States)

    2008-10-30

    Hydrogen-rich environments such as fuel cell reactors can exhibit damage caused by hydrogen permeation in the form of corrosion cracking by lowering tensile strength and decreasing material ductility. Coatings and liners have been investigated, but there were few shot-peening or laser peening studies referenced in the literature with respect to preventing hydrogen embrittlement. The surface compressive residual stress induced by laser peening had shown success in preventing stress corrosion cracking (SCC) for stainless steels in power plants. The question arose if the residual stresses induced by laser peening could delay the effects of hydrogen in a material. This study investigated the effect of laser peening on hydrogen penetration into metal alloys. Three areas were studied: laser peening, hydrogenation, and hydrogen detection. This study demonstrated that laser peening does not reduce the hydrogen permeation into a stainless steel surface nor does it prevent hydrogen embrittlement. The effect of laser peening to reduce hydrogen-assisted fatigue was unclear.

  18. High temperature damage of a re-sulfurized stainless steel

    International Nuclear Information System (INIS)

    Tinet, Hougo

    2002-01-01

    After having evoked the industrial problem raised by high-temperature damage in the 303 stainless steel, and outlined that the experimental study of high-temperature damage implies the study of the sane (or non damaged) material, the study of micro-voids germination, growth and coalescence, and the study of the material failure process, the author of this research thesis reports a bibliographical study on the behaviour of sane re-sulfurized stainless steel and different damage models. He presents experimental techniques (thermal-mechanical compression and tensile tests, image analysis in optical microscopy) which have been used in this work, and describes and comments results obtained on axisymmetric samples for micro-void germination, growth and coalescence in case of a damage under low and medium stress triaxiality. The last part addresses the study of the damage of strongly notched samples (stress triaxialities close to those existing at the crack bottom) [fr

  19. Electrochemical evaluation of crevice corrosion in stainless steels

    International Nuclear Information System (INIS)

    Flyg, J.; Jargelius-Pettersson, R.F.A.

    1998-01-01

    An electrochemical method for the evaluation of crevice corrosion in stainless steels is described. Specimens are carefully abraded in order to give a large number of microcrevices when the specimen is placed in contact with a rubber o-ring. Twelve specimens are tested simultaneously in a purpose-built electrochemical cell. A constant potential is applied to the specimens and the temperature automatically raised at intervals until a current increase indicates the onset of crevice corrosion and thereby defines the critical crevice corrosion temperature (CCT). Testing has been performed on a wide range of stainless steels in 3.5% NaCl at +700 mV SCE. The temperature was raised by 5 C every 70 minutes. Results show good reproducibility with a typical standard deviation of below 5 C. There is also excellent agreement with the ranking of crevice corrosion resistance for different steel grades which is obtained by immersion testing in 6% FeCl 3 solution. (orig.)

  20. Tensile properties of the modified 13Cr martensitic stainless steels

    International Nuclear Information System (INIS)

    Mabruri, Efendi; Anwar, Moch Syaiful; Prifiharni, Siska; Romijarso, Toni B.; Adjiantoro, Bintang

    2016-01-01

    This paper reports the influence of Mo and Ni on the tensile properties of the modified 13Cr martensitic stainless steels in tempered condition. Four steels with different content of Mo and Ni were prepared by induction melting followed by hot forging, quenching and tempering. The experimental results showed that the addition of about 1% and 3% Mo has a beneficial effect to increase both the tensile strength and the elongation of the steels. On the contrary, the addition of about 3% Ni into the martensitic stainless steel results in decreasing of both the tensile strength and the elongation. Among the alloys investigated the 13Cr3Mo type steel exhibited largest tensile strength of 1348 MPa and largest elongation of 12%. The observation on the tensile fractured surfaces by using scanning electron microscope supported these findings.

  1. Electroless Plated Nanodiamond Coating for Stainless Steel Passivation

    Energy Technology Data Exchange (ETDEWEB)

    Li, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Korinko, P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Spencer, W. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Stein, E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-09-15

    Tritium gas sample bottles and manifold components require passivation surface treatments to minimize the interaction of the hydrogen isotopes with surface contamination on the stainless steel containment materials. This document summarizes the effort to evaluate electroless plated nanodiamond coatings as a passivation layer for stainless steel. In this work, we developed an electroless nanodiamond (ND)-copper (Cu) coating process to deposit ND on stainless steel parts with the diamond loadings of 0%, 25% and 50% v/v in a Cu matrix. The coated Conflat Flanged Vessel Assemblies (CFVAs) were evaluated on surface morphology, composition, ND distribution, residual hydrogen release, and surface reactivity with deuterium. For as-received Cu and ND-Cu coated CFVAs, hydrogen off-gassing is rapid, and the off-gas rates of H2 was one to two orders of magnitude higher than that for both untreated and electropolished stainless steel CFVAs, and hydrogen and deuterium reacted to form HD as well. These results indicated that residual H2 was entrapped in the Cu and ND-Cu coated CFVAs during the coating process, and moisture was adsorbed on the surface, and ND and/or Cu might facilitate catalytic isotope exchange reaction for HD formation. However, hydrocarbons (i.e., CH3) did not form, and did not appear to be an issue for the Cu and ND-Cu coated CFVAs. After vacuum heating, residual H2 and adsorbed H2O in the Cu and ND-Cu coated CFVAs were dramatically reduced. The H2 off-gassing rate after the vacuum treatment of Cu and 50% ND-Cu coated CFVAs was on the level of 10-14 l mbar/s cm2, while H2O off-gas rate was on the level of 10-15 l mbar/s cm2, consistent with the untreated or electropolished stainless steel CFVA, but the HD formation remained. The Restek EP bottle was used as a reference for this work. The Restek Electro-Polished (EP) bottle and their Sil

  2. Inhibition of Sodium Benzoate on Stainless Steel in Tropical Seawater

    International Nuclear Information System (INIS)

    Seoh, S. Y.; Senin, H. B.; Nik, W. N. Wan; Amin, M. M.

    2007-01-01

    The inhibition of sodium benzoate for stainless steel controlling corrosion was studied in seawater at room temperature. Three sets of sample have been immersed in seawater containing sodium benzoate with the concentrations of 0.3M, 0.6M and 1.0M respectively. One set of sample has been immersed in seawater without adding any sodium benzoate. It was found that the highest corrosion rate was observed for the stainless steel with no inhibitor was added to the seawater. As the concentration of sodium benzoate being increased, the corrosion rate is decreases. Results show that by the addition of 1.0M of sodium benzoate in seawater samples, it giving ≥ 90% efficiencies

  3. Attack polish for nickel-base alloys and stainless steels

    Science.gov (United States)

    Not Available

    1980-05-28

    A chemical attack polish and polishing procedure for use on metal surfaces such as nickel base alloys and stainless steels is described. The chemical attack polich comprises FeNO/sub 3/, concentrated CH/sub 3/COOH, concentrated H/sub 2/SO/sub 4/ and H/sub 2/O. The polishing procedure includes saturating a polishing cloth with the chemical attack polish and submicron abrasive particles and buffing the metal surface.

  4. Method of polishing nickel-base alloys and stainless steels

    Science.gov (United States)

    Steeves, Arthur F.; Buono, Donald P.

    1981-01-01

    A chemical attack polish and polishing procedure for use on metal surfaces such as nickel base alloys and stainless steels. The chemical attack polish comprises Fe(NO.sub.3).sub.3, concentrated CH.sub.3 COOH, concentrated H.sub.2 SO.sub.4 and H.sub.2 O. The polishing procedure includes saturating a polishing cloth with the chemical attack polish and submicron abrasive particles and buffing the metal surface.

  5. Martensite transformations influence in austenite stainless steel fractures

    International Nuclear Information System (INIS)

    Fonseca, H.; Monteiro, S.N.

    1976-07-01

    The influence of martensitic transformation on the fracture of tensile specimens of type AISI 310, and type 302, stainless steels was studied in the temperature interval from 25 0 C to -196 0 C. The influence of the metastability through the amount and rate of martensite transformation leading to high stresses and work hardening, apparently explains the brittle characteristics observed in the fracture of type 302 alloy as well as its ductile nature at -196 0 C [pt

  6. EXAFS investigation of low temperature nitrided stainless steel

    DEFF Research Database (Denmark)

    Oddershede, Jette; Christiansen, Thomas; Ståhl, Kenny

    2008-01-01

    contents: (1) nitriding in pure NH3 and (2)nitriding in pure NH3 followed by reduction in H2. The majority of the Cr atoms in the stainless steel after treatment 1 and 2 was associated with a nitrogen–chromium bond distance comparable to that of the chemical compound CrN. The possibility of the occurrence...... of mixed substitutional– interstitial atom clusters or coherent nitride platelets in nitrogen-expanded austenite is discussed....

  7. Market Opportunities for Austenitic Stainless Steels in SO2 Scrubbers

    Science.gov (United States)

    Michels, Harold T.

    1980-10-01

    Recent U.S. federal legislation has created new opportunities for SO2 scrubbers because all coals, even low-sulfur western coals, will probably require scrubbing to remove SO2 from gaseous combustion products. Scrubbing, the chemical absorption of SO2 by vigorous contact with a slurry—usually lime or limestone—creates an aggressive acid-chloride solution. This presents a promising market for pitting-resistant austenitic stainless steels, but there is active competition from rubber and fiberglass-lined carbon steel. Since the latter are favored on a first-cost basis, stainless steels must be justified on a cost/performance or life-cost basis. Nickel-containing austenitic alloys are favored because of superior field fabricability. Ferritic stainless steels have little utility in this application because of limitations in weldability and resulting poor corrosion resistance. Inco corrosion test spools indicate that molybdenum-containing austenitic alloys are needed. The leanest alloys for this application are 316L and 317L. Low-carbon grades of stainless steel are specified to minimize corrosion in the vicinity of welds. More highly alloyed materials may be required in critical areas. At present, 16,000 MW of scrubber capacity is operational and 17,000 MW is under construction. Another 29,000 MW is planned, bringing the total to 62,000 MW. Some 160,000 MW of scrubber capacity is expected to be placed in service over the next 10 years. This could translate into a total potential market of 80,000 tons of alloy plate for new power industry construction in the next decade. Retrofitting of existing power plants plus scrubbers for other applications such as inert gas generators for oil tankers, smelters, municipal incinerators, coke ovens, the pulp and paper industry, sulfuric acid plants, and fluoride control in phosphoric acid plants will add to this large market.

  8. Versatility of superaustenitic stainless steels in marine applications

    International Nuclear Information System (INIS)

    Latha, G.; Rajeswari, S.

    1996-01-01

    Corrosion of construction materials in marine applications is a major problem. The frequent variations in chloride ion concentration and temperature experienced by a system pose a serious threat. This investigation evaluated the performance of superaustenitic stainless steels in marine applications by potentiodynamic anodic polarization studies. The concentrations of metal ions such as iron, chromium, and nickel at different impressed potentials were analyzed by inductively coupled plasma spectrometry, which revealed little tendency for leaching of metal ions

  9. Corrosion Properties of Sintered and Wrought Stainless Seel

    DEFF Research Database (Denmark)

    Mathiesen, Troels; Maahn, Ernst Emanuel

    1997-01-01

    The corrosion properties of a range of stainless steels produced by powder metallurgy (PM) are compared with wrought AISI304 and AISI316 Steel. Characterisation of the passivation properties in 0.5M H2SO4 and pittingresistance in 0.3% chloride solution by polarisation show properties...... of the sintered PM150 that are comparable or better than those of wrought 316 steel depending on the applied sintering technique....

  10. Corrosion Testing of Stainless Steel Fuel Cell Hardware

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, M.S.; Zawodzinski, C.; Gottesfeld, S.

    1998-11-01

    Metal hardware is gaining increasing interest in polymer electrolyte fuel cell (PEFC) development as a possible alternative to machined graphite hardware because of its potential for low-cost manufacturing combined with its intrinsic high conductivity, minimal permeability and advantageous mechanical properties. A major barrier to more widespread use of metal hardware has been the susceptibility of various metals to corrosion. Few pure metals can withstand the relatively aggressive environment of a fuel cell and thus the choices for hardware are quite limited. Precious metals such as platinum or gold are prohibitively expensive and so tend to be utilized as coatings on inexpensive substrates such as aluminum or stainless steel. The main challenge with coatings has been to achieve pin-hole free surfaces that will remain so after years of use. Titanium has been used to some extent and though it is very corrosion-resistant, it is also relatively expensive and often still requires some manner of surface coating to prevent the formation of a poorly conducting oxide layer. In contrast, metal alloys may hold promise as potentially low-cost, corrosion-resistant materials for bipolar plates. The dozens of commercially available stainless steel and nickel based alloys have been specifically formulated to offer a particular advantage depending upon their application. In the case of austenitic stainless steels, for example, 316 SS contains molybdenum and a higher chromium content than its more common counterpart, 304 SS, that makes it more noble and increases its corrosion resistance. Likewise, 316L SS contains less carbon than 316 SS to make it easier to weld. A number of promising corrosion-resistant, highly noble alloys such as Hastelloy{trademark} or Duplex{trademark} (a stainless steel developed for seawater service) are available commercially, but are expensive and difficult to obtain in various forms (i.e. wire screen, foil, etc.) or in small amounts for R and D

  11. Creep embrittlement of austenitic stainless steels with titanium addition

    International Nuclear Information System (INIS)

    Felsen, M.F.

    1983-04-01

    Some cold-worked austenitic stainless steels of the 316 type with titanium addition exhibit a low creep ductility and a notch sensitivity in the temperature range of 550 0 C to 750 0 C and for times to rupture from 10 to 10000 hours. It has been shown that this embrittlement increases highly with cold-work percentage, with solution annealing temperature, and depends on chemical composition because these factors can modify the difference of hardness between grains and grain boundaries

  12. Internal frictions of austenitic stainless steels at low temperature

    Science.gov (United States)

    Tsubono, K.; Owa, S.; Mio, N.; Akasaka, N.; Hirakawa, H.

    Internal frictions were measured for three types of austenitic stainless steel, AISI 304, 310S and 316, in the temperature range 4-300 K. The intrinsic friction is presented in terms of the quality factor of a 20 kHz eigenmode vibration of discs made from each material. Temperature dependence is also given for the resonant frequency of each disc. These mechanical properties show some peculiarities at low temperature.

  13. Welding Characteristics of Nitrogen Added Stainless Steels for Nuclear Application

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Y. D. [Pohang Iron and Steel Co., Ltd, Pohang (Korea, Republic of)

    1997-07-01

    Characteristics of properties and manufacturing process was evaluated in development of high strength and corrosion resistant stainless steel. The continuous cast structure of STS 316L was similar to that of STS 304. The most of residual {delta}-ferrite of STS 316L was vermicular type. The residual {delta}-ferrite content increased from the surface towards the center of the slab and after reaching a maximum value at about 50mm distance from surface and steeply decreased towards the center itself. Hot ductility of STS 304L and STS 316L stainless steels containing below 1000 ppm N was appeared to be reasonably good in the range of hot rolling temperature. In case of the steels containing over 1000 ppm N, the hot ductility was decreased rapidly when sulfur content of the steel was above 20 ppm. Therefore, to achieve good hot ductility of the high nitrogen containing steel, reduction of sulfur contents is required as low as possible. The inter granular corrosion resistance and impact toughness of STS 316L were increased with increasing the nitrogen contents. Yield strength and tensile strength of 304 and 316 stainless steels are increased linearly with increasing the nitrogen contents but their elongations are decreased with increasing the nitrogen contents. Therefore, the mechanical properties of these stainless steels could be controlled with variation of nitrogen. The effects of nitrogen on the resistance of stress corrosion cracking (SCC) can be explained by improvement of the load bearing capacity with increasing tensile strength rather than inhibition of trans granular SCC crack generation and propagation. 101 refs., 17 tabs., 105 figs. (author)

  14. Electrochemical reduction of hydrogen peroxide on stainless steel

    Indian Academy of Sciences (India)

    Administrator

    commercial 304 grade stainless steel (SS) foil. (thickness: 0⋅2 mm) was used as the substrate for. H2O2 reduction. A solution of 0⋅5 M NaClO4. (pH = 5⋅8) was .... oxide layers, unlike mediation of the reduction by. CuO present on Cu. A mechanism involving decomposition (or dis- proportionation) of H2O2 leading to the ...

  15. Instrumental Neuron Activation Analysis for certification of stainless steel materials

    International Nuclear Information System (INIS)

    Polkowska-Motrenko, H.

    2006-01-01

    The use of Instrumental Neuron Activation Analysis (INAA) may contribute to improve the certification of the materials, especially in the case of minor and trace elements. In presented paper the INAA method of analysis of stainless steel materials has been elaborated. The obtained results were compared with those of common analytical techniques. The presented results show the usefulness of the INAA method for the certification of CRMs for the iron and steel industry

  16. Pitting Corrosion Susceptibility of AISI 301 Stainless Steel in ...

    African Journals Online (AJOL)

    The susceptibility of austenitic (AISI 301) stainless steel to pitting corrosion was evaluated in sodium chloride (NaCl) solutions - 0.1M, 0.2M, 0.3M, 0.5M and 0.7M and 1.0M. Tensile tests and microscopic examinations were performed on samples prepared from the steel after exposure in the various environments.

  17. Simulation of Friction Stir Processing in 304L Stainless Steel

    Directory of Open Access Journals (Sweden)

    Miles M.P.

    2016-01-01

    Full Text Available A major dilemma facing the nuclear industry is repair or replacement of stainless steel reactor components that have been exposed to neutron irradiation. When conventional fusion welding is used for weld repair, the high temperatures and thermal stresses inherent in the process enhance the growth of helium bubbles, causing intergranular cracking in the heat-affected zone (HAZ. Friction stir processing (FSP has potential as a weld repair technique for irradiated stainless steel, because it operates at much lower temperatures than fusion welding, and is therefore less likely to cause cracking in the HAZ. Numerical simulation of the FSP process in 304L stainless steel was performed using an Eulerian finite element approach. Model input required flow stresses for the large range of strain rates and temperatures inherent in the FSP process. Temperature predictions in three locations adjacent to the stir zone were accurate to within 4% of experimentally measure values. Prediction of recrystallized grain size at a location about 6mm behind the tool center was less accurate, because the empirical model employed for the prediction did not account for grain growth that occurred after deformation in the experiment was halted.

  18. Biomonitoring of genotoxic exposure among stainless steel welders

    DEFF Research Database (Denmark)

    Knudsen, Lisbeth E.; Boisen, T; Christensen, J M

    1992-01-01

    A biosurvey in the Danish metal industry measured the genotoxic exposure from stainless steel welding. The study comprised measurements of chromosomal aberrations (CA), sister-chromatid exchanges (SCE), unscheduled DNA synthesis (UDS) in peripheral lymphocytes and serum immunoglobulin G. Environm......A biosurvey in the Danish metal industry measured the genotoxic exposure from stainless steel welding. The study comprised measurements of chromosomal aberrations (CA), sister-chromatid exchanges (SCE), unscheduled DNA synthesis (UDS) in peripheral lymphocytes and serum immunoglobulin G....... Environmental monitoring of welding fumes and selected metal oxides, biomonitoring of chromium and nickel in serum and urine and mutagenic activity in urine, and evaluation of semen quality were also done. Manual metal arc (MMA) welding and tungsten inert gas (TIG) welding were the dominant welding processes...... lymphocytes in exposed persons compared with non-exposed are suggested. MMA welding gave the highest exposure to chromium, an increased number of chromosomal aberrations and a decrease in SCE when compared with TIG welding. Consequently improvements in the occupational practice of stainless steel welding...

  19. Stainless steel and polyethylene surfaces functionalized with silver nanoparticles.

    Science.gov (United States)

    Fialho, José Fq; Naves, Emiliane Aa; Bernardes, Patrícia C; Ferreira, Deusmaque C; Dos Anjos, Letícia D; Gelamo, Rogério V; de Sá, João Pn; de Andrade, Nélio J

    2018-01-01

    The antimicrobial effects of a stainless steel surface and a polyethylene surface functionalized with silver nanoparticles on the adhesion of different bacteria and the changes in physical and chemical characteristics of these surfaces that influence biofilm formation were evaluated. The functionalized surfaces of polyethylene and stainless steel were more hydrophobic than the control ones. The bacterial surfaces were hydrophilic. The adhesion of all bacteria was thermodynamically favorable (ΔG adhesion functionalized and control. The numbers of adhered cells of Staphylococcus aureus, Escherichia coli, and Pseudomonas fluorescens were not significantly different (p > 0.05) between the control and functionalized surfaces, reaching values compatible with biofilm formation. Analysis of atomic absorption spectrometry using water and reconstituted skim milk as simulants showed no release of Ag from the functionalized surfaces. In conclusion, the surfaces that were functionalized with silver nanoparticles were modified in hydrophobicity, roughness, and did not avoid bacterial adhesion. Additional studies of surfaces functionalized with silver nanoparticles should be conducted addressing the adsorption technique of silver nanoparticles on the stainless steel surface as well as in the preparation of the polyethylene surface to allow the contact of microorganism with the antimicrobial agent.

  20. Effect of dual torch technique on duplex stainless steel welds

    International Nuclear Information System (INIS)

    Sun, Z.; Kuo, M.; Annergren, I.; Pan, D.

    2003-01-01

    Duplex stainless steels are characterized by balanced ferrite/austenite microstructures and are well known for their superior corrosion resistance and higher strength compared with the common austenitic stainless steels. One major concern, however, is that welding might degrade the corrosion resistance by producing unbalanced phase content, detrimental precipitates, and possible embrittlement of the weldment. In this paper, a dual-torch arc welding technique (plasma torch followed by a gas tungsten arc (GTA) torch) was proposed. Effects of the dual-torch technique on the microstructural changes and corrosion properties were investigated. The preliminary study indicated that a correlation between the welding parameters and the microstructural changes and corrosion resistance existed. It was found that the corrosion rate increases with increasing torch pitch and/or decreasing GTA welding current. By adjusting the distance between the torches, modification of weld microstructure may be realized. Although further studies are required to fine-tune the technique, the present study demonstrated the potential of using dual torch technique to improve weldability of duplex stainless steels

  1. Study on Thermal Physical Properties of 304 Stainless Steel

    Science.gov (United States)

    Fang, Dong; Jun-mao, Qie; Hao-hua, Deng

    The DIL402C thermal dilatometer and STA449C thermal analyzer were employed to test the linear expansion and contraction coefficient, CP and DSC curve of 304 stainless steel. The result showed that the linear expansion coefficient range was 20.9700×10-6˜21.5712×10-6 and the linear contraction coefficient range was 21.2528×10-6˜21.9471×10-6. The linear expansion and contraction coefficient were higher than other steel grade, so the 304 stainless steel belonged to the crack sensitive steel. Because of the crystal phase transformation occurred during the 1000˜1400 °C,the curve of CP fluctuated obviously and the defects of casting blank occurred easily. Chosen 1414°C as the liquidus temperature of 304 stainless steel based on the analysis results of DSC. The curve of DSC was unsmooth during 1450˜1100°C, the crystal phase transformation occurs and thermal stability of slab was inferior.When the initial solidified shell formed in this temperature range,the thickness of the shell would be nonuniform and the surface defects occurred more easily.

  2. Mechanical Properties of Austenitic Stainless Steel Made by Additive Manufacturing

    Science.gov (United States)

    Luecke, William E; Slotwinski, John A

    2014-01-01

    Using uniaxial tensile and hardness testing, we evaluated the variability and anisotropy of the mechanical properties of an austenitic stainless steel, UNS S17400, manufactured by an additive process, selective laser melting. Like wrought materials, the mechanical properties depend on the orientation introduced by the processing. The recommended stress-relief heat treatment increases the tensile strength, reduces the yield strength, and decreases the extent of the discontinuous yielding. The mechanical properties, assessed by hardness, are very uniform across the build plate, but the stress-relief heat treatment introduced a small non-uniformity that had no correlation to position on the build plate. Analysis of the mechanical property behavior resulted in four conclusions. (1) The within-build and build-to-build tensile properties of the UNS S17400 stainless steel are less repeatable than mature engineering structural alloys, but similar to other structural alloys made by additive manufacturing. (2) The anisotropy of the mechanical properties of the UNS S17400 material of this study is larger than that of mature structural alloys, but is similar to other structural alloys made by additive manufacturing. (3) The tensile mechanical properties of the UNS S17400 material fabricated by selective laser melting are very different from those of wrought, heat-treated 17-4PH stainless steel. (4) The large discontinuous yielding strain in all tests resulted from the formation and propagation of Lüders bands. PMID:26601037

  3. Accumulative Roll Bonding of Aluminum/Stainless Steel Sheets

    Directory of Open Access Journals (Sweden)

    Navid Mohammad Nejad Fard

    2017-06-01

    Full Text Available An Al/Stainless Steel/Al lamellar composite was produced by roll bonding of the starting sheets at 400 °C. Afterward, the roll bonded sheet was cut in half and the accumulative roll bonding (ARB process at room temperature was applied seven times. As a result, the central steel layer fractured and distributed in the Al matrix among different layers introduced by the repetition of roll bonding process. The tensile results showed that the roll bonded sheet has much higher strength and strength to weight ratio compared with the initial aluminum sheet as a result of the presence of continuous steel core. However, poor ductility properties were observed during tensile test, which were ascribed to the increasing deformation resistance and localized thinning of the central stainless steel sheet during the roll bonding process. The ARBed sample exhibited lower strength compared with the roll bonded sheet due to the breakup of stainless steel layer into many small segments. Anyway, an ultrafine grained microstructure with average grain size of 400 nm in the aluminum matrix and 71% strain-induced martensite in the steel segments were detected by the electron backscattered diffraction (EBSD technique, which were found to be responsible for the enhancement of mechanical properties compared with the initial aluminum sheet.

  4. Mechanical characteristics of welded joints between different stainless steels grades

    Science.gov (United States)

    Topolska, S.; Łabanowski, J.

    2017-08-01

    Investigation of mechanical characteristics of welded joints is one of the most important tasks that allow determining their functional properties. Due to the very high, still rising, cost of some stainless steels it is justified, on economic grounds, welding austenitic stainless steel with steels that are corrosion-resistant like duplex ones. According to forecasts the price of corrosion resistant steels stil can increase by 26 ÷ 30%. For technical reasons welded joints require appropriate mechanical properties such as: tensile strength, bending, ductility, toughness, and resistance to aggressive media. Such joints are applied in the construction of chemical tankers, apparatus and chemical plants and power steam stations. Using the proper binder makes possible the welds directly between the elements of austenitic stainless steels and duplex ones. It causes that such joits behave satisfactorily in service in such areas like maritime constructions and steam and chemical plants. These steels have high mechanical properties such as: the yield strength, the tensile strength and the ductility as well as the resistance to general corrosion media. They are resistant to both pitting and stress corrosions. The relatively low cost of production of duplex steels, in comparison with standard austenitic steels, is inter alia, the result of a reduced amount of scarce and expensive Nickel, which is seen as a further advantage of these steels.

  5. Corrosion Performance of Stainless Steels in a Simulated Launch Environment

    Science.gov (United States)

    Calle, Luz Marina; Vinje, Rubiela D.; MacDowell, Louis

    2004-01-01

    At the Kennedy Space Center, NASA relies on stainless steel (SS) tubing to supply the gases and fluids required to launch the Space Shuttle. 300 series SS tubing has been used for decades but the highly corrosive environment at the launch pad has proven to be detrimental to these alloys. An upgrade with higher alloy content materials has become necessary in order to provide a safer and long lasting launch facility. In the effort to find the most suitable material to replace the existing AISI 304L SS ([iNS S30403) and AISI 316L SS (UNS S31603) shuttle tubing, a study involving atmospheric exposure at the corrosion test site near the launch pads and electrochemical measurements is being conducted. This paper presents the results of an investigation in which stainless steels of the 300 series, 304L, 316L, and AISI 317L SS (UNS S31703) as well as highly alloyed stainless steels 254-SMO (UNS S32154), AL-6XN (N08367) and AL29-4C ([iNS S44735) were evaluated using direct current (DC) electrochemical techniques under conditions designed to simulate those found at the Space Shuttle Launch pad. The electrochemical results were compared to the atmospheric exposure data and evaluated for their ability to predict the long-term corrosion performance of the alloys.

  6. Stress corrosion cracking evaluation of martensitic precipitation hardening stainless steels

    Science.gov (United States)

    Humphries, T. S.; Nelson, E. E.

    1980-01-01

    The resistance of the martensitic precipitation hardening stainless steels PH13-8Mo, 15-5PH, and 17-4PH to stress corrosion cracking was investigated. Round tensile and c-ring type specimens taken from several heats of the three alloys were stressed up to 100 percent of their yield strengths and exposed to alternate immersion in salt water, to salt spray, and to a seacoast environment. The results indicate that 15-5PH is highly resistant to stress corrosion cracking in conditions H1000 and H1050 and is moderately resistant in condition H900. The stress corrosion cracking resistance of PH13-8Mo and 17-4PH stainless steels in conditions H1000 and H1050 was sensitive to mill heats and ranged from low to high among the several heats included in the tests. Based on a comparison with data from seacoast environmental tests, it is apparent that alternate immersion in 3.5 percent salt water is not a suitable medium for accelerated stress corrosion testing of these pH stainless steels.

  7. High specialty stainless steels and nickel alloys for FGD dampers

    Energy Technology Data Exchange (ETDEWEB)

    Herda, W.R.; Rockel, M.B.; Grossmann, G.K. [Krupp VDM GmbH, Werdohl (Germany); Starke, K. [Mannesmann-Seiffert GmbH, Beckum (Germany)

    1997-08-01

    Because of process design and construction, FGD installations normally have bypass ducts, which necessitates use of dampers. Due to corrosion from acid dew resulting from interaction of hot acidic flue gases and colder outside environments, carbon steel cannot be used as construction material under these specific conditions. In the past, commercial stainless steels have suffered by pitting and crevice corrosion and occasionally failed by stress corrosion cracking. Only high alloy specialty super-austenitic stainless steels with 6.5% Mo should be used and considered for this application. Experience in Germany and Europe has shown that with regard to safety and life cycle cost analysis as well as providing a long time warranty, a new specialty stainless steel, alloy 31--UNS N08031--(31 Ni, 27 Cr, 6.5 Mo, 0.2 N) has proven to be the best and most economical choice. Hundreds of tons in forms of sheet, rod and bar, as well as strip (for damper seals) have been used and installed in many FGD installations throughout Europe. Under extremely corrosive conditions, the new advanced Ni-Cr-Mo alloy 59--UNS N06059--(59 Ni, 23 Cr, 16 Mo) should be used. This paper describes qualification and workability of these alloys as pertains to damper applications. Some case histories are also provided.

  8. The repair of preveneered posterior stainless steel crowns.

    Science.gov (United States)

    Yilmaz, Yucel; Gurbuz, Taskin; Eyuboglu, Ozge; Belduz, Nihal

    2008-01-01

    This study's purposes were to determine the shear bond strength (SBS) for and to perform dye penetration (microleakage) and scanning electron microscopy (SEM) evaluations of preveneered posterior stainless steel crowns (SSCs) that were repaired using 2 different materials. Twenty-two crowns were used. They were stored in artificial saliva for 30 days and then thermocycled. A force was applied on the crowns' occlusal surfaces until the original veneer material appeared to be fractured. The fracture types and S8S values were recorded. The crowns were then repaired using Panavia opaque cement and Tetric Flow or Monoopaque and Tetric Flow. Twenty of the repaired crowns were subjected to dye penetration and SBS tests, and the remaining 2 were evaluated using SEM. Statistical analysis revealed no statistically significant differences in the results of either the S8S or the dye penetration test (P = .58 and P = 38, respectively). A statistically significant difference was found between original and repaired crowns regarding fracture extent (P = .02), but not failure type (P = .08). SEM evaluation showed that there was no observable gap at the interface of the original or repaired materials and the stainless steel base. Preveneered posterior stainless steel crowns may be repaired using either repair material types tested here.

  9. Development of nuclear grade stainless steels at KCSSL

    International Nuclear Information System (INIS)

    Balachandran, G.; Dhere, M.; Mahadik, A.; Hinge, N.M.; Balasubramanian, V.

    2011-01-01

    Kalyani Carpenter Special Steels Ltd is an alloy steel plant, where a variety of alloy steel grades are produced for automotive, defence, nuclear and aerospace applications. The plant has developed expertise in processing of several alloy steel grades of superior quality that meets stringent specifications. Primary steel is processed through a combination of electric arc furnace, ladle furnace and vacuum degassing where stringent control over dephosphorisation, desulphurization, deoxidation is effected to get a refined high quality steel. The molten steel is cast through continuous casting of slabs or ingot casting. In grades specific to nuclear application, the primary cast products are further subjected to electroslag remelting to achieve further freedom from inclusions and to achieve a favourable solidification grain structure, which ultimately improve the hot workability of the alloy steel. Appropriate choice of slag and operating parameters are needed for realising the required ingot quality. The present study would examine the processing and quality aspects of some important grades of steels used in nuclear industry namely ferritic 9Cr-1Mo steel, martensitic stainless steels 403, 410, precipitation hardenable 17-4 PH stainless steel and austenitic 321, 316LN stainless steel, which were made and supplied for applications to Indian nuclear industry. The expertise developed in processing the steels in terms of melting, heat treatment and their relationship to structural features and mechanical properties would be highlighted. (author)

  10. Mechanical Properties of Austenitic Stainless Steel Made by Additive Manufacturing.

    Science.gov (United States)

    Luecke, William E; Slotwinski, John A

    2014-01-01

    Using uniaxial tensile and hardness testing, we evaluated the variability and anisotropy of the mechanical properties of an austenitic stainless steel, UNS S17400, manufactured by an additive process, selective laser melting. Like wrought materials, the mechanical properties depend on the orientation introduced by the processing. The recommended stress-relief heat treatment increases the tensile strength, reduces the yield strength, and decreases the extent of the discontinuous yielding. The mechanical properties, assessed by hardness, are very uniform across the build plate, but the stress-relief heat treatment introduced a small non-uniformity that had no correlation to position on the build plate. Analysis of the mechanical property behavior resulted in four conclusions. (1) The within-build and build-to-build tensile properties of the UNS S17400 stainless steel are less repeatable than mature engineering structural alloys, but similar to other structural alloys made by additive manufacturing. (2) The anisotropy of the mechanical properties of the UNS S17400 material of this study is larger than that of mature structural alloys, but is similar to other structural alloys made by additive manufacturing. (3) The tensile mechanical properties of the UNS S17400 material fabricated by selective laser melting are very different from those of wrought, heat-treated 17-4PH stainless steel. (4) The large discontinuous yielding strain in all tests resulted from the formation and propagation of Lüders bands.

  11. Surface interactions of cesium and boric acid with stainless steel

    International Nuclear Information System (INIS)

    Grossman-Canfield, N.

    1995-08-01

    In this report, the effects of cesium hydroxide and boric acid on oxidized stainless steel surfaces at high temperatures and near one atmosphere of pressure are investigated. This is the first experimental investigation of this chemical system. The experimental investigations were performed using a mass spectrometer and a mass electrobalance. Surfaces from the different experiments were examined using a scanning electron microscope to identify the presence of deposited species, and electron spectroscopy for chemical analysis to identify the species deposited on the surface. A better understanding of the equilibrium thermodynamics, the kinetics of the steam-accelerated volatilizations, and the release kinetics are gained by these experiments. The release rate is characterized by bulk vaporization/gas-phase mass transfer data. The analysis couples vaporization, deposition, and desorption of the compounds formed by cesium hydroxide and boric acid under conditions similar to what is expected during certain nuclear reactor accidents. This study shows that cesium deposits on an oxidized stainless steel surface at temperatures between 1000 and 1200 Kelvin. Cesium also deposits on stainless steel surfaces coated with boric oxide in the same temperature ranges. The mechanism for cesium deposition onto the oxide layer was found to involve the chemical reaction between cesium and chromate. Some revaporization in the cesium hydroxide-boric acid system was observed. It has been found that under the conditions given, boric acid will react with cesium hydroxide to form cesium metaborate. A model is proposed for this chemical reaction

  12. EFFECT OF INTERMETALLIC PHASES ON CORROSION BEHAVIOR AND MECHANICAL PROPERTIES OF DUPLEX STAINLESS STEEL AND SUPER-DUPLEX STAINLESS STEEL

    Directory of Open Access Journals (Sweden)

    Prabhu Paulraj

    2015-08-01

    Full Text Available Duplex Stainless Steels (DSS and Super Duplex Stainless Steel (SDSS have excellent integration of mechanical and corrosion properties. However, the formation of intermetallic phases is a major problem in their usage. The mechanical and corrosion properties are deteriorated due to the presence of intermetallic phases. These phases are induced during welding, prolonged exposure to high temperatures, and improper heat treatments. The main emphasis of this review article is on intermetallic phases and their effects on corrosion and mechanical properties. First the effect of various alloying elements on DSS and SDSS has been discussed followed by formation of various intermetallic phases. The intermetallic phases affect impact toughness and corrosion resistance significantly. Their deleterious effect on weldments has also been reviewed.

  13. Blast and Fragment Protective Sandwich Panel Concepts for Stainless Steel Monohull Designs

    Science.gov (United States)

    2008-10-21

    and Johnson-Cook parameters for AISI 304 stainless steel used in the numerical analyses. 3. Experimental results 3.1. Honeycomb panels. 3.1.1...20Cr-2Mn-lSi (wt%). The material proper- ties for AISI 304 stainless steel are reported in Table 2. A slotted metal sheet assembly approach was used...Figure 3. AISI 304 stainless steel panel with square honeycomb core, (a) Solid-ring spacers were employed to prevent core crushing while fastening the

  14. Corrosion And Thermal Processing In Cold Gas Dynamic Spray Deposited Austenitic Stainless Steel Coatings

    Science.gov (United States)

    2016-06-01

    testing (ASTM G5) of low pressure cold spray austenitic stainless steel coatings. Several different powders and heat treatments will be applied to...diffusion eliminating the local low chromium region. The low carbon type stainless steel alloys as used here are generally considered to be...maximum 200words) This thesis presents research on the corrosion properties and effects of heat treatment on austenitic stainless steel coatings

  15. Particle Impact Ignition Test Data on a Stainless Steel Hand Valve

    Science.gov (United States)

    Peralta, Stephen

    2010-01-01

    This slide presentation reviews the particle impact ignition test of a stainless steel hand valve. The impact of particles is a real fire hazard with stainless steel hand valves, however 100 mg of particulate can be tolerated. Since it is unlikely that 100 mg of stainless steel contaminant particles can be simultaneously released into this type of valve in the WSTF configuration, this is acceptable and within statistical confidence as demonstrated by testing.

  16. Controlling radiation induced segregation in austenitic stainless steels

    International Nuclear Information System (INIS)

    Ahmedabadi, Parag M.; Kain, Vivekanand

    2011-01-01

    In-core components of austenitic stainless steels in light water reactors (LWRs) are susceptible to irradiation assisted stress corrosion cracking (IASCC) in high temperature and high pressure oxygenated water at temperature around 300 deg C . Though, the exact mechanism for IASCC is not fully understood, radiation-induced segregation (RIS) is considered to be a part of a complex process that leads to IASCC. Therefore, controlling RIS in austenitic stainless steels may lead to improvement in resistance to IASCC. RIS is non-equilibrium segregation/depletion of alloying elements in austenitic stainless steels at LWR operating temperatures. RIS occurs due to adsorption of point defects at grain boundaries and leads to segregation of Si and P and depletion of Cr at grain boundaries. Thus by controlling point defect flux towards grain boundaries, the extent of RIS at grain boundaries can be controlled. An extensive study was carried out to simulate and control RIS in austenitic stainless steels using proton irradiation at 300 deg C . The primary aim of this study was to reduce point defect flux towards grain boundaries. Various approaches viz. grain boundary engineering, addition of oversized alloying element, residual strain within matrix and presence of fine precipitates within the grains and at grain boundaries were employed to control RIS in austenitic stainless steels. A novel approach involving combination of electrochemical technique followed by atomic force microscopic (AFM) examination has been used to examine the nature and the extent of RIS. Type 304, 316 and 347 stainless steels were irradiated at 300 deg C (in FOTIA and PELLETRON) in the range of 0.2 to 1.0 dpa using proton beam. The results obtained so far have indicated that a small amount of pre-strain within the grains is very effective in reducing the flux of point defects towards grain boundaries and reducing the extent of RIS at grain boundaries. The presence of NbC precipitates within the grains is

  17. General and Localized corrosion of Austenitic and Borated Stainless Steels in Simulated Concentrated Ground Waters

    International Nuclear Information System (INIS)

    Fix, D.; Estill, J.; Wong, L.; Rebak, R.

    2004-01-01

    Boron containing stainless steels are used in the nuclear industry for applications such as spent fuel storage, control rods and shielding. It was of interest to compare the corrosion resistance of three borated stainless steels with standard austenitic alloy materials such as type 304 and 316 stainless steels. Tests were conducted in three simulated concentrated ground waters at 90 C. Results show that the borated stainless were less resistant to corrosion than the witness austenitic materials. An acidic concentrated ground water was more aggressive than an alkaline concentrated ground water

  18. Electrochemical and passivation behavior investigation of ferritic stainless steel in simulated concrete pore media.

    Science.gov (United States)

    Luo, Hong; Su, Huaizhi; Dong, Chaofang; Xiao, Kui; Li, Xiaogang

    2015-12-01

    The applications of stainless steel are one of the most reliable solutions in concrete structures to reduce chloride-induced corrosion problems and increase the structures service life, however, due to high prices of nickel, especially in many civil engineering projects, the austenitic stainless steel is replaced by the ferritic stainless steels. Compared with austenite stainless steel, the ferritic stainless steel is known to be extremely resistant of stress corrosion cracking and other properties. The good corrosion resistance of the stainless steel is due to the formation of passive film. While, there is little literature about the electrochemical and passive behavior of ferritic stainless steel in the concrete environments. So, here, we present the several corrosion testing methods, such as the potentiodynamic measurements, EIS and Mott-Schottky approach, and the surface analysis methods like XPS and AES to display the passivation behavior of 430 ferritic stainless steel in alkaline solution with the presence of chloride ions. These research results illustrated a simple and facile approach for studying the electrochemical and passivation behavior of stainless steel in the concrete pore environments.

  19. Effects of Thermal Aging on Type 316H Stainless Steel for Reactor Vessel

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Ji Hyun; Hong, Seok Min; Lee, Bong Sang; Koo, Gyeong Hoi [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    Type 316H stainless steel is a prime candidate for reactor vessel material of sodium-cooled fast reactor (SFR) which has been developed as one of the Gen IV nuclear reactors in Korea. The reactor vessel steel will be exposed to higher temperature for an extended design life time. It is known that austenitic stainless steel such as Type 316H stainless steel shows excellent toughness and adequate strength at a moderate temperature. However, the previous researches reported the mechanical properties of Type 316H stainless weld would be deteriorated by the aging at the elevated temperature range.

  20. Corrosion study of stainless steels in a dissolver off-gas environment

    International Nuclear Information System (INIS)

    Suzuki, K.; Tsukaue, Y.; Yoshida, K.; Hirose, Y.

    1991-01-01

    Iodine induced corrosion characteristics of stainless steels have been studied under various case of simulated dissolver off-gas environment. No corrosion of any kind of stainless steel so far tested was observed under typical dissolver off-gas environment, containing HNO 3 and NOx as well as I 2 . Pitting corrosion was observed, however, in humid air containing I 2 but no HNO 3 nor NOx, depending upon I 2 concentration on certain types of stainless steel. The higher content of Mo in stainless steels, the less depth of pitting was measured. A mechanism based on iodine concentration in water film on metal surface, was proposed to explain above phenomena. (author)

  1. NDE of explosion welded copper stainless steel first wall mock-up

    International Nuclear Information System (INIS)

    Taehtinen, S.; Kauppinen, P.; Jeskanen, H.; Lahdenperae, K.; Ehrnsten, U.

    1997-04-01

    The study showed that reflection type C-mode scanning acoustic microscope (C-SAM) and internal ultrasonic inspection (IRIS) equipment can be applied for ultrasonic examination of copper stainless steel compound structures of ITER first wall mock-ups. Explosive welding can be applied to manufacture fully bonded copper stainless steel compound plates. However, explosives can be applied only for mechanical tightening of stainless steel cooling tubes within copper plate. If metallurgical bonding between stainless steel tubes and copper plate is required Hot Isostatic Pressing (HIP) method can be applied. (orig.)

  2. HIP bonding for the different material between Niobium and Stainless steel

    International Nuclear Information System (INIS)

    Inoue, H.; Saito, K.; Abe, K.; Fujino, T.; Hitomi, N.; Kobayashi, Y.

    2000-01-01

    In the future advanced cryomodule for superconducting RF cavities, a helium vessel made from titanium or stainless steel has to be welded directly to the niobium cavity wall in order to be simple structure. For that, we need a transformer from niobium to titanium or stainless steel. Stainless steel will have many benefits if the reliable bonding to the niobium is developed. We have tested the niobium/stainless steel bonding by HIP (Hot Isostatic Pressing) with the heat shock between 1023K and 2K. The bonding interface was also observed by SEM. These test results will be presented. (author)

  3. Maintenance versus non-maintenance intravesical Bacillus Calmette-Guerin instillation for non-muscle invasive bladder cancer: A systematic review and meta-analysis of randomized clinical trials.

    Science.gov (United States)

    Chen, Siteng; Zhang, Ning; Shao, Jialiang; Wang, Xiang

    2018-02-28

    It is not clear whether maintenance Bacillus Calmette-Guerin (BCG) is necessary for intermediate- or high-risk non-muscle-invasive bladder cancer (NMIBC). This systematic review and meta-analysis aimed to illustrate the effects of maintenance BCG for intermediate- or high-risk NMIBC. A comprehensive literature search of PubMed, EMBASE, Cochrane Library, ClinicalTrials.gov databases and International Clinical Trials Register (ICTRP) Search was conducted to identify relevant randomized controlled trials (RCTs) that have assessed the efficacy of maintenance or non-maintenance BCG therapy for patients with NMIBC. The maintenance group first received induction BCG instillations, and subsequently received BCG intravesical instillations regularly for at least 1 year, while the control group only received induction BCG instillations. Systematic review and meta-analysis were performed according to Preferred Reporting Items for Systematic Reviews and Meta-analysis Criteria. Ten RCTs were eligible in this systematic review. The meta-analysis showed that induction BCG followed by maintenance BCG instillation after transurethral resection (TUR) could reduce the risk ratios of tumor recurrence by 21% (RR = 0.79; 95% CI 0.70-0.89; P maintenance BCG. It could also reduce the risk ratios of tumor progression (RR = 0.81; 95% CI 0.68-0.97; P = 0.02). However, these pooled results should be considered with caution since the quality of evidences for outcomes ranged low. Subgroup analysis implied that different durations of maintenance BCG instillations might be one of the sources of potential clinical heterogeneity of included studies. Begg's funnel plot and Egger's test did not reveal any evidence of publication bias in this meta-analysis. Induction BCG followed by maintenance BCG instillation after TUR, compared with induction BCG along, can reduce the risk ratios of tumor recurrence and tumor progression, and prolong RFS. However, these results with a lower level of

  4. The Effect of Negative Pressure Wound Therapy With Antiseptic Instillation on Biofilm Formation in a Porcine Model of Infected Spinal Instrumentation.

    Science.gov (United States)

    Singh, Devinder P; Gowda, Arvind U; Chopra, Karan; Tholen, Michael; Chang, Sarah; Mavrophilipos, Vasilios; Semsarzadeh, Nina; Rasko, Yvonne; Holton Iii, Luther

    2017-06-01

    This study evaluates the effect of negative pressure wound therapy with antiseptic instillation (NPWTi) in the clearance of infection and biofilm formation in an in vivo model of infected spinal implants compared to traditional treatment modalities. Five pigs underwent titanium rod implantation of their spinous processes followed by injection of 1 x 106 CFUs/100μL of methicillin-resistant Staphylococcus aureus through the fascia at each site. At 1 week postoperatively, an experimental arm of 3 pigs received NPWTi, and a control arm of 2 pigs received wet-to-dry dressings. The persistence of local infection in the experimental group was compared to the control group using tissue cultures. Biofilm development on spinal implants was evaluated using scanning electron microscopy. Mean bacterial count showed a statistical difference between the experimental and the control groups (P < .05). Scanning electron microscopy revealed the presence of uniform biofilm formation across the surface of control group instrumentation, whereas the experimental group showed interrupted areas between biofilm formations. The authors concluded that NPWTi is associated with decreased bacterial load and biofilm formation compared to wet-to-dry dressings in an in vivo porcine model of infected spinal instrumentation.

  5. [Fever, Hepatic Dysfunction and Interstitial Pneumonia Caused by Intravesical Bacillus Calmette-Guerin (BCG) Instillation after Urethral Bougie : A Case Report].

    Science.gov (United States)

    Nitta, Satoshi; Sakka, Shotaro; Endo, Tsuyoshi; Komine, Manabu; Tsutsumi, Masakazu; Nishiyama, Hiroyuki

    2017-10-01

    A 60-year-old man had a past history of urothelial carcinoma of the left renal pelvis treated with laparoscopic left total nephroureterectomy in October 2004. He underwent transurethral resection of the bladder tumor (TUR-Bt) twice for recurrence of urothelial carcinoma in the bladder in April 2014 and February 2015, and subsequently received intravesical Bacillus Calmette-Guerin (BCG) instillation at weekly intervalsfor prevention of recurrence. In November 2016, a year and a half after BCG induction, he received BCG therapy after urethral bougie to dilate the urethral stricture. After BCG therapy, he exhibited a continuously high fever. Immediate antituberculosis drug therapy in consideration of BCG sepsis failed to improve the symptoms, and all cultures from urine and blood were negative for mycobacterium tuberculosis. Serum liver enzyme was markedly elevated and chest CT showed diffuse interstitial shadows in both lower lungs. Thus, we considered that these symptoms were caused by a hypersensitivity reaction to BCG and started pulse steroid therapy. After pulse steroid therapy, body temperature, and hepatic function became normal and interstitial pneumonia subsided.

  6. Outcomes following intra-amniotic instillation with indigo carmine to diagnose prelabor rupture of membranes in singleton pregnancies: a single center experience.

    Science.gov (United States)

    Adekola, Henry; Gill, Navleen; Sakr, Sharif; Hobson, Deslyn; Bryant, David; Abramowicz, Jacques S; Soto, Eleazar

    2016-01-01

    To evaluate clinical outcomes of women with singleton pregnancies that underwent intra-amniotic dye instillation (amniodye test) following equivocal diagnosis of prelabor rupture of membranes (PROM). Records of 34 pregnant women who underwent amniodye test for equivocal PROM were reviewed. Comparisons of characteristics, amniotic fluid (AF) cultures, AF interleukin (IL)-6 concentrations, and placenta pathology results between women who tested positive and those who tested negative were performed. A sub-analysis of women who were amniodye test-negative was also performed. (1) Commonest indication for amniodye test was a typical history of PROM with positive conventional tests and persistently normal AF volume, (2) amniodye test-positive women had a shorter procedure-to-delivery interval (p = 0.008), and a greater proportion of histologic acute chorioamnionitis (p = 0.04) and funisitis (p = 0.01) than amniodye-negative women, and (3) in addition to similarities to women with amniodye-positive test, amniodye test-negative women who delivered <34 weeks, had a greater proportion of women with risk for preterm birth (p = 0.04), than their counterparts who delivered between 34 0/7 and 36 6/7 weeks. Equivocal diagnosis of PPROM should warrant an amniodye test to avoid iatrogenic intervention in women with intact amniotic membranes. AF analysis should be performed in amniodye test-negative women.

  7. Aging and Embrittlement of High Fluence Stainless Steels

    Energy Technology Data Exchange (ETDEWEB)

    Was, gary; Jiao, Zhijie; der ven, Anton Van; Bruemmer, Stephen; Edwards, Dan

    2012-12-31

    Irradiation of austenitic stainless steels results in the formation of dislocation loops, stacking fault tetrahedral, Ni-Si clusters and radiation-induced segregation (RIS). Of these features, it is the formation of precipitates which is most likely to impact the mechanical integrity at high dose. Unlike dislocation loops and RIS, precipitates exhibit an incubation period that can extend from 10 to 46 dpa, above which the cluster composition changes and a separate phase, (G-phase) forms. Both neutron and heavy ion irradiation showed that these clusters develop slowly and continue to evolve beyond 100 dpa. Overall, this work shows that the irradiated microstructure features produced by heavy ion irradiation are remarkably comparable in nature to those produced by neutron irradiation at much lower dose rates. The use of a temperature shift to account for the higher damage rate in heavy ion irradiation results in a fairly good match in the dislocation loop microstructure and the precipitate microstructure in austenitic stainless steels. Both irradiations also show segregation of the same elements and in the same directions, but to achieve comparable magnitudes, heavy ion irradiation must be conducted at a much higher temperature than that which produces a match with loops and precipitates. First-principles modeling has confirmed that the formation of Ni-Si precipitates under irradiation is likely caused by supersaturation of solute to defect sinks caused by highly correlated diffusion of Ni and Si. Thus, the formation and evolution of Ni-Si precipitates at high dose in austenitic stainless steels containing Si is inevitable.

  8. The role of duplex stainless steels for downhole tubulars

    International Nuclear Information System (INIS)

    Francis, R.

    1993-01-01

    In sour conditions there is an increasing trend to turn to corrosion resistant alloys for downhole tubulars. The most commonly used CRA tubular is 13Cr, and there are thousands of feet in service. However, there are limits to the use of 13Cr, ie., the risk of sulphide stress corrosion cracking at high H 2 S levels, and the possibility of pitting or high corrosion rates in waters with high chloride contents. Where the service conditions are felt to be too severe for 13Cr alloys it has been traditional to switch to nickel base alloys such as alloys 825 and C-276 (UNS N08825 and N10276). The alloys are much more expensive than 13Cr, and in recent years the duplex stainless steels have been selected as alloys with superior corrosion and SSCC resistance compared with 13Cr, and having lower cost than nickel alloys. Originally the 22Cr duplex alloy (UNS 31803) was used, but more recently the 25Cr super duplex alloys (UNS S32760 and S32750) have become more available. The present paper reviews the data available for 13Cr and the limits of applicability. Data is also presented for laboratory tests for both the 22Cr and 25Cr super duplex alloys. There is extensive service experience with both 22Cr and 25Cr super duplex in the North Sea, covering both downhole tubulars, manifold and post wellhead equipment. Data is presented showing some of the sour condition being experienced in the North Sea by super duplex alloys. These results show that there is a substantial gap between the limits of use for 13Cr and the 25Cr super duplex stainless steel alloys. This means that in many sour environments super duplex stainless steel provides a cost effective alternative to nickel-base alloys

  9. Creep rupture properties of oxidised 20%Cr austenitic stainless steels

    International Nuclear Information System (INIS)

    Lobb, R.C.; Ecob, R.C.

    1989-02-01

    Sheet specimens of stabilised 20%Cr/25%Ni/Nb and nitrided 20%Cr/25%Ni/Ti stainless steels, both used as fuel cladding materials in CAGRs, have been oxidised in simulated reactor gas (Co 2 /1-2%CO) for up to l.9kh at 850 0 C, including intermediate thermal cycles to room temperature. The oxidised specimens have been creep tested subsequently at 750 0 C, under conditions of constant stress. The creep rupture properties are affected differently for the two materials. For 20%Cr/25%Ni/Nb stainless steel, there was no effect of oxidation on the intrinsic microstructure, when compared with thermally aged, non-oxidised material. Any differences in creep ductility were ascribed to geometric effects in specimens of this alloy. Lower ductilities were associated with an increased incidence of pitting attack (higher oxide spallation) and it was concluded that the extent of local, rather than general, loss of section controlled the ductility. For nitrided 20%Cr/25%Ni/Ti stainless steel, the intrinsic microstructure was affected by oxidation, such that increased grain boundary precipitation of M 23 C 6 occurred. The resultant effect was for a greater tendency for intergranular failure at lower ductility than for the thermally aged material. The magnitude of this reduction could not be quantified because the specimen geometry was also changed by oxidation. In this instance, the oxidation mode that produced the most severe loss of section was grain boundary, rather than pitting, attack. This mode of attack was not linked directly to oxide fracture/spallation, but to the period of oxidation. (author)

  10. Experimental Study Of Fog Water Harvesting By Stainless Steel Mesh

    OpenAIRE

    Nikhil R. Pawar; Suman S. Jain; Smitha R. God

    2017-01-01

    The collection of fog water is a simple and sustainable technology to get hold of fresh water for various purposes. In areas where a substantial amount of fog can be obtained it is feasible to set up a stainless steel as well as black double layer plastic mesh structure for fog water harvesting. The mesh structure is directly exposed to the weather and the fog containing air is pushed through the active mesh surface by the wind. Afterward fog droplets are deposited on the active mesh area whi...

  11. Electrochemical noise measurements of stainless steel in high temperature water

    International Nuclear Information System (INIS)

    Arganis-Juarez, C.R.; Malo, J.M.; Uruchurtu, J.

    2007-01-01

    Corrosion in a high purity aqueous environment simulating a boiling water reactor (BWR) is addressed in this work. This condition necessitates autoclave experiments under high pressure and temperature. Long-term electrochemical noise measurements were explored as a mean to detect and monitor stress corrosion cracking phenomenon. An experimental set up, designed to insulate the working electrode from external interference, made possible to detect and monitor stress corrosion cracking in slow strain rate tests for sensitized and solution annealed 304 stainless steel at 288 o C. Time-series analysis showed variations in the signature of the current density series due to transgranular stress corrosion cracking (TGSCC) and intergranular stress corrosion cracking (IGSCC)

  12. Evaluation of Cutting Fluids in Multiple Reaming of Stainless Steel

    DEFF Research Database (Denmark)

    Belluco, Walter; Zeng, Z.; De Chiffre, Leonardo

    2001-01-01

    An investigation on the effect of different cutting fluids in reaming is presented. The performance of three water based cutting fluids and one cutting oil was compared to that of a reference water based commercial product by measurement of cutting forces, surface roughness and part accuracy. Three...... subsequent reaming operations were carried out on austenitic stainless steel using high-speed-steel and solid carbide tools. The tested fluids were all significantly different from the reference fluid in at least some of the tested conditions. Significant differences down to 2 percent in cutting forces and 6...

  13. High cycle fatigue of Type 422 stainless steel

    International Nuclear Information System (INIS)

    Soo, P.; Chow, J.G.Y.; Sabatini, R.L.

    1978-01-01

    High cycle fatigue testing has been carried out on Type 422 stainless steel to determine the performance of cyclically stressed disks and blades in the main and auxiliary HTGR helium circulators. Tests were performed at 316, 482, and 538 0 C (600, 900, and 1000 0 F) in air for the fully reversible and mean load conditions. Goodman's analysis is shown to be valid in predicting failure at 316 0 C (600 0 F), marginally valid at 482 0 C (900 0 F), and probably invalid at 538 0 C (1000 0 F). Metallographic analyses were conducted to characterize the nature of failure for the temperatures and loading conditions investigated

  14. High Nitrogen Austenitic Stainless Steel Precipitation During Isothermal Annealing

    Directory of Open Access Journals (Sweden)

    Maria Domankova

    2016-07-01

    Full Text Available The time-temperature-precipitation in high-nitrogen austenitic stainless steel was investigated using light optical microscopy, transmission electron microscopy, selected area diffraction and energy-dispersive X-ray spectroscopy. The isothermal precipitation kinetics curves and the corresponding precipitation activation energy were obtained. The diffusion activation energy of M2N precipitation is 129 kJ/mol. The results show that critical temperature for M2N precipitation is about 825°C with the corresponding incubation period 2.5 min.

  15. Cutting of Stainless Steel With Fiber and Disk Laser

    DEFF Research Database (Denmark)

    Wandera, Catherine; Salminen, Antti; Olsen, Flemming Ove

    2006-01-01

    role also in cutting applications. This has not happened mainly due to the fact that beam quality has not been sufficient. The introduction of new generation of solid state lasers has raised the interest of use of them in cutting application. This study was concentrated on use of fiber and disk lasers......, the new laser types with a high beam quality, in cutting of austenitic stainless steel. The performance of these new lasers at power level of 4 kW was compared with CO2-laser in respect of cutting speed, kerf width, kerf edge roughness and perpendicularity (squarness) in order to validate the potential...

  16. Austenite stability in the high strength metastable stainless steels

    OpenAIRE

    S.J. Pawlak

    2007-01-01

    Purpose: The aim of the present paper was to study the peculiarities of the austenite to martensite phase transformation (A-M), which is an essential step in the production technology of the high strength metastable stainless steels.Design/methodology/approach: The desired control over A-M transformation have been achieved by proper design of the steel chemistry, cold working and heat treatment.Findings: For a range of steel compositions, it was shown that severe cold working leads to fully m...

  17. SELECTIVE SEPARATION OF URANIUM FROM FERRITIC STAINLESS STEELS

    Science.gov (United States)

    Beaver, R.J.; Cherubini, J.H.

    1963-05-14

    A process is described for separating uranium from a nuclear fuel element comprising a uranium-containing core and a ferritic stainless steel clad by heating said element in a non-carburizing atmosphere at a temperature in the range 850-1050 un. Concent 85% C, rapidly cooling the heated element through the temperature range 815 un. Concent 85% to 650 EC to avoid annealing said steel, and then contacting the cooled element with an aqueous solution of nitric acid to selectively dissolve the uranium. (AEC)

  18. Compatibility of stainless steel with Pb-17 AT. % Li

    International Nuclear Information System (INIS)

    Tortorelli, P.F.; DeVan, J.H.

    1982-01-01

    The corrosion of type 316 stainless steel and Sandvik HT9 by static Pb-17 at. % Li between 300 and 500 0 C was studied. The resulting weight losses were significantly greater than those of these steels in lithium. The corrosive attack was very uniform, and the room-temperature tensile properties of the steels were unaffected by the exposure. The application of molten Pb-17 at. % Li as a tritium-breeding fluid in conjunction with ferrous alloys in a fusion reactor may be limited to 400 0 C or below

  19. Physical properties of the AISI 348 L* austenitic stainless steel

    International Nuclear Information System (INIS)

    Teodoro, Celso Antonio; Lucki, Georgi; Silva, Jose Eduardo Rosa da; Terremoto, Luis Antanio Albiac; Castanheira, Myrthes; Damy, Margaret de Almeida

    2005-01-01

    The study of radiation damage in metals and alloys, used as structural materials of nuclear reactors has a strategic meaning in nuclear technology, because it allows the performance evaluation of these materials in working conditions of PWR. For this sake it is necessary to know the detrimental structural changes that occur during fast neutron irradiation. The aim of the present work is to show some strain-stress results of the AISI 348 L * stainless steel utilized as a structural material of the fuel elements of PWR, in comparison with the AISI 304. (author)

  20. Recycled hydroxyapatite coatings on 316L stainless steel substrates

    International Nuclear Information System (INIS)

    Mendes Filho, Antonio Alves; Pereira, Renato Alves; Araujo, Fernando Gabriel da Silva; Sousa, Camila Mateus de

    2010-01-01

    In this work were evaluated recycled hydroxyapatite coatings on 316L stainless steel substrates by plasma thermal aspersion. The hydroxyapatite used was obtained from bovine bone by the hydrothermal method. The samples of hydroxyapatite powders were divided according to their particle size distribution. The adhesion of the powders coating to the substrate was evaluated by assay scratch. The X-ray diffraction techniques and scanning electron microscopy were also used. The results of scratch resistance were between 46N and 63N. Analysis by scanning electron microscopy and x-ray diffraction showed no cracks coatings, single-phase and with few fused particles. (author)