WorldWideScience

Sample records for american pit viper

  1. Neutralization of lethality and proteolytic activities of Malayan pit viper (Calloselasma rhodostoma) venom with North American Virginia opossum (Didelphis virginiana) serum.

    Science.gov (United States)

    Pornmanee, Piboon; Sánchez, Elda E; López, Gonzalo; Petsom, Amorn; Khow, Orawan; Pakmanee, Narumol; Chanhome, Lawan; Sangvanich, Polkit; Pérez, John C

    2008-07-01

    Malayan pit viper (Calloselasma rhodostoma) envenomation is a major health problem in South East Asia. During envenomation, venom components mainly affect the hemostatic system. The sera from the North American Virginia opossums (Didelphis virginiana) were able to neutralize the venom of the Malayan pit viper. These natural inhibitors could be explored as potential therapeutics against envenomations of a variety of venomous snake species in different geographical habitats.

  2. Effect of Trimeresurus albolabris (green pit viper) venom on mean ...

    African Journals Online (AJOL)

    An in vitro study was conducted by mixing small amounts of green pit viper venom with blood and observing changes. At a concentration of 10 mg crude venom, red blood cells (RBC) osmotic fragility slightly increased. RBC morphology changed to spherical shape which was compatible with what was observed in scanning ...

  3. PRESUMPTIVE PIT VIPER ENVENOMATION IN PSITTACINES IN A BRAZILIAN ZOO.

    Science.gov (United States)

    Dislich, Mathias; Wohlsein, Peter; Croukamp, Anna Sophie; Neumann, Ulrich

    2017-09-01

    Snake bites represent a serious public health risk in many regions of the globe, especially in tropical areas. Clinical signs and postmortem changes are well described in human and other mammalian species. However, detailed case reports about venomous snake attacks in avian species are limited. This report describes presumptive fatal envenomations in three psittacines caused by pit vipers in a Brazilian zoo. In one case, a Brazilian lancehead (Bothrops moojeni) was captured in the aviary. In all three cases the dermis around the suspected snake bite area exhibited hemorrhages and edema. Histologically, degeneration and necrosis of subcutaneous musculature were observed. Lung, heart, and kidneys displayed focal hemorrhages. The local changes are similar to those described for mammalian patients including humans. However, except for the parenchymatous hemorrhages, additional external and internal gross and histopathological lesions were missing. After ruling out other causes, such as aggression and dicoumarinic intoxication, the presumptive diagnosis of snake envenomation was made. The smaller size and variabilities of pathophysiological effects of the venom in parrots might explain the different lesion patterns observed, compared with mammals. Possibly, the birds may have reacted differently to envenomation by pit vipers and died before the venom could cause macroscopic and histological changes often observed in mammals.

  4. Lessons Learned from Pit Viper Integration into Hanford Tank Farm Reality

    International Nuclear Information System (INIS)

    Catalan, Michael A.; Bailey, Sharon A.; Alzheimer, James M.; Niebuhr, Daniel P.

    2002-01-01

    The Pit Viper is a tele-operated system intended to enhance worker safety while simultaneously improving the efficiency of pit operations at the Hanford Site. Commercial off-the-shelf (COTS) components were used in an attempt to increase system efficiency. During preparation for initial deployment, the Pit Viper team identified multiple areas where more advanced technology offers substantial improvement in system capabilities. The team also ensured that the system as is, was capable of fulfilling its mission. However, there are valid concerns of the reliability of the technology. Areas where improvement are desired include; operator feedback, manipulator dexterous envelope, and system reliability

  5. Microhabitat Assessment of Mangrove Pit Viper Cryptelytrops purpureomaculatus in Restricted Mangrove Area, Dumai, Riau Province, Sumatera

    Directory of Open Access Journals (Sweden)

    Nia Kurniawan

    2017-06-01

    Full Text Available Bandar Bakau is a mangrove conservation area with approximately 20 ha that preserves many kinds of fauna, including Mangrove Pit Viper Cryptelytrops purpureomaculatus. However, this species and its habitat are still poorly studied in Indonesia, particularly Sumatera island, despite it has a wide distribution in Southeast Asian countries. The main purpose of this study is to evaluate the microhabitat of Mangrove Pit Viper C. purpureomaculatus that found at a restricted mangrove area in Dumai, Riau Province. Visual Encounter Survey (VES and deep interview methods were used in this study. The survey found six individuals of C. purpureomaculatus that mostly basking on the Avicennia marina and artificial building. Although Bandar Bakau is a tourism object, but no snakebite cases were found.

  6. Microangiopathic Hemolytic Anemia Following Three Different Species of Hump-Nosed Pit Viper (Genus: Hypnale) Envenoming in Sri Lanka.

    Science.gov (United States)

    Namal Rathnayaka, Rathnayaka Mudiyanselage M K; Ranathunga, Anusha Nishanthi; Kularatne, Senanayake A M; Rajapakse, Jayanthe; Ranasinghe, Shirani; Jayathunga, Radha

    2018-03-01

    There are 3 species of hump-nosed pit vipers in Sri Lanka: Hypnale hypnale, Hypnale zara, and Hypnale nepa. The latter 2 are endemic to the country. Microangiopathic hemolytic anemia (MAHA) is a known complication of hump-nosed pit viper bites. It was previously documented as a complication of general viper bites and not species specific. We report a series of 3 patients who developed MAHA after being bitten by each species of hump-nosed pit viper. The first patient was bitten by H hypnale and developed a severe form of MAHA associated with acute kidney injury and thrombocytopenia falling into the category of thrombotic microangiopathy. The other 2 developed MAHA that resolved without any complications. Copyright © 2017 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

  7. The thermal background determines how the infrared and visual systems interact in pit vipers.

    Science.gov (United States)

    Chen, Qin; Liu, Yang; Brauth, Steven E; Fang, Guangzhan; Tang, Yezhong

    2017-09-01

    The thermal infrared (IR) sensing system of pit vipers is believed to complement vision and provide a substitute imaging system in dark environments. Theoretically, the IR system would best image a scene consisting of a homothermal target in cold surroundings as a bright spot on a dark background. To test this hypothesis, we evaluated how the pit viper ( Gloydius brevicaudus ) discriminates and strikes prey when the background temperature is either higher or lower than that of the prey (approximately 32-33°C) in different parts of the scene. Snakes were tested in a modified predation cage in which background temperatures were set to 26°C on one side and either 33 or 40°C on the opposite side when the eyes, the pit organs or neither sensory system was occluded. When the eyes were blocked, snakes preferred to strike prey on the 26°C side rather than on the 33°C side but showed no bias in the other conditions. Snakes showed no preference for 26 versus 40°C background temperature, although more missed strikes occurred when the eyes were occluded. The results thus revealed that the pit viper IR system can accomplish a 'brightness constancy' computation reflecting the difference between the target and background temperatures, much as the visual system compares the luminance of a figure and the background. Furthermore, the results show that the IR system performs less well for locating prey when the background is warmer than the target. © 2017. Published by The Company of Biologists Ltd.

  8. Venomics of New World pit vipers: genus-wide comparisons of venom proteomes across Agkistrodon.

    Science.gov (United States)

    Lomonte, Bruno; Tsai, Wan-Chih; Ureña-Diaz, Juan Manuel; Sanz, Libia; Mora-Obando, Diana; Sánchez, Elda E; Fry, Bryan G; Gutiérrez, José María; Gibbs, H Lisle; Sovic, Michael G; Calvete, Juan J

    2014-01-16

    We report a genus-wide comparison of venom proteome variation across New World pit vipers in the genus Agkistrodon. Despite the wide variety of habitats occupied by this genus and that all its taxa feed on diverse species of vertebrates and invertebrate prey, the venom proteomes of copperheads, cottonmouths, and cantils are remarkably similar, both in the type and relative abundance of their different toxin families. The venoms from all the eleven species and subspecies sampled showed relatively similar proteolytic and PLA2 activities. In contrast, quantitative differences were observed in hemorrhagic and myotoxic activities in mice. The highest myotoxic activity was observed with the venoms of A. b. bilineatus, followed by A. p. piscivorus, whereas the venoms of A. c. contortrix and A. p. leucostoma induced the lowest myotoxic activity. The venoms of Agkistrodon bilineatus subspecies showed the highest hemorrhagic activity and A. c. contortrix the lowest. Compositional and toxicological analyses agree with clinical observations of envenomations by Agkistrodon in the USA and Central America. A comparative analysis of Agkistrodon shows that venom divergence tracks phylogeny of this genus to a greater extent than in Sistrurus rattlesnakes, suggesting that the distinct natural histories of Agkistrodon and Sistrurus clades may have played a key role in molding the patterns of evolution of their venom protein genes. A deep understanding of the structural and functional profiles of venoms and of the principles governing the evolution of venomous systems is a goal of venomics. Isolated proteomics analyses have been conducted on venoms from many species of vipers and pit vipers. However, making sense of these large inventories of data requires the integration of this information across multiple species to identify evolutionary and ecological trends. Our genus-wide venomics study provides a comprehensive overview of the toxic arsenal across Agkistrodon and a ground for

  9. Venomics of New World pit vipers: Genus-wide comparisons of venom proteomes across Agkistrodon

    Science.gov (United States)

    Lomonte, Bruno; Tsai, Wan-Chih; Ureña-Diaz, Juan Manuel; Sanz, Libia; Mora-Obando, Diana; Sánchez, Elda E.; Fry, Bryan G.; Gutiérrez, José María; Gibbs, H. Lisle; Sovic, Michael G.; Calvete, Juan J.

    2015-01-01

    We report a genus-wide comparison of venom proteome variation across New World pit vipers in the genus Agkistrodon. Despite the wide variety of habitats occupied by this genus and that all its taxa feed on diverse species of vertebrates and invertebrate prey, the venom proteomes of copperheads, cottonmouths, and cantils are remarkably similar, both in the type and relative abundance of their different toxin families. The venoms from all the eleven species and subspecies sampled showed relatively similar proteolytic and PLA2 activities. In contrast, quantitative differences were observed in hemorrhagic and myotoxic activities in mice. The highest myotoxic activity was observed with the venoms of A. b. bilineatus, followed by A. p. piscivorus, whereas the venoms of A. c. contortrix and A. p. leucostoma induced the lowest myotoxic activity. The venoms of Agkistrodon bilineatus subspecies showed the highest hemorrhagic activity and A. c. contortrix the lowest. Compositional and toxicological analyses agree with clinical observations of envenomations by Agkistrodon in the USA and Central America. A comparative analysis of Agkistrodon shows that venom divergence tracks phylogeny of this genus to a greater extent than in Sistrurus rattlesnakes, suggesting that the distinct natural histories of Agkistrodon and Sistrurus clades may have played a key role in molding the patterns of evolution of their venom protein genes. Biological significance A deep understanding of the structural and functional profiles of venoms and of the principles governing the evolution of venomous systems is a goal of venomics. Isolated proteomics analyses have been conducted on venoms from many species of vipers and pit vipers. However, making sense of these large inventories of data requires the integration of this information across multiple species to identify evolutionary and ecological trends. Our genus-wide venomics study provides a comprehensive overview of the toxic arsenal across

  10. Identification and functional analysis of a novel bradykinin inhibitory peptide in the venoms of New World Crotalinae pit vipers

    International Nuclear Information System (INIS)

    James Graham, Robert Leslie; Graham, Ciaren; McClean, Stephen; Chen, Tianbao; O'Rourke, Martin; Hirst, David; Theakston, David; Shaw, Chris

    2005-01-01

    A novel undecapeptide has been isolated and structurally characterized from the venoms of three species of New World pit vipers from the subfamily, Crotalinae. These include the Mexican moccasin (Agkistrodon bilineatus), the prairie rattlesnake (Crotalus viridis viridis), and the South American bushmaster (Lachesis muta). The peptide was purified from all three venoms using a combination of gel permeation chromatography and reverse-phase HPLC. Automated Edman degradation sequencing and MALDI-TOF mass spectrometry established its peptide primary structure as: Thr-Pro-Pro-Ala-Gly-Pro-Asp-Val-Gly-Pro-Arg-OH, with a non-protonated molecular mass of 1063.18 Da. A synthetic replicate of the peptide was found to be an antagonist of bradykinin action at the rat vascular B2 receptor. This is the first bradykinin inhibitory peptide isolated from snake venom. Database searching revealed the peptide to be highly structurally related (10/11 residues) with a domain residing between the bradykinin-potentiating peptide and C-type natriuretic peptide domains of a recently cloned precursor from tropical rattlesnake (Crotalus durissus terrificus) venom gland. BIP thus represents a novel biological entity from snake venom

  11. Venoms of South Asian hump-nosed pit vipers (Genus: Hypnale cause muscarinic effects in BALB/c mice

    Directory of Open Access Journals (Sweden)

    A Silva

    2014-03-01

    Full Text Available Although clinical, in-vivo and in-vitro studies suggest the necrotic, haemorrhagic, pro-coagulant and nephrotoxic effects of South Asian Hump nosed pit vipers, reports on neurotoxic properties are limited to a single in-vitro study. Using BALB/c mice, for the first time, here we demonstrate the signs of envenoming suggestive of possible muscarinic effects of the venoms of all three Hypnale species. Further, we demonstrate that the muscarinic effects are occurred at lower venom doses by H. hypnale venom, compared to H. nepa and H. zara.

  12. Cross-recognition of a pit viper (Crotalinae) polyspecific antivenom explored through high-density peptide microarray epitope mapping

    DEFF Research Database (Denmark)

    Engmark, Mikael; Lomonte, Bruno; Gutiérrez, José María

    2017-01-01

    Snakebite antivenom is a 120 years old invention based on polyclonal mixtures of antibodies purified from the blood of hyper-immunized animals. Knowledge on antibody recognition sites (epitopes) on snake venom proteins is limited, but may be used to provide molecular level explanations...... for antivenom cross-reactivity. In turn, this may help guide antivenom development by elucidating immunological biases in existing antivenoms. In this study, we have identified and characterized linear elements of B-cell epitopes from 870 pit viper venom protein sequences by employing a high......-throughput methodology based on custom designed high-density peptide microarrays. By combining data on antibody-peptide interactions with multiple sequence alignments of homologous toxin sequences and protein modelling, we have determined linear elements of antibody binding sites for snake venom metalloproteases (SVMPs...

  13. Comparative in-vivo toxicity of venoms from South Asian hump-nosed pit vipers (Viperidae: Crotalinae: Hypnale

    Directory of Open Access Journals (Sweden)

    Silva Anjana

    2012-08-01

    Full Text Available Abstract Background Envenoming by south Asian hump-nosed pit vipers (Genus: Hypnale is a significant health issue in Sri Lanka and in peninsular India. Bites by these snakes frequently lead to local envenoming, coagulopathy and acute renal failure even resulting in death. Recently the genus was revised and the existence of three species viz H. hypnale, H. nepa and H. zara were recognized. There is, however, a paucity of information on the toxicity of the venoms of these species. Hence, we compared the toxic effects of the three Hypnale venoms using BALB/c mice. Findings Intraperitoneal median lethal doses (LD50 for H. hypnale, H. zara and H. nepa venoms were 1.6, 6.0 and 9.5 μg protein/g respectively. Minimum haemorrhagic doses for venoms of H. hypnale, H. zara and H. nepa were 3.4, 11.0 and 16.6 μg protein/mouse respectively. The minimum necrotic doses for the same venoms were 15.0, 55.1 and 68.2 μg protein/mouse respectively. Severe congestion and petecheal haemorrhages were observed in lungs, kidneys, liver and the alimentary tract. Histopathogical examination of kidneys revealed proximal tubular cell injury and acute tubular necrosis with intact basement membrane indicating possible direct nephrotoxicity. Hypnale venoms caused pulmonary oedema, hepatocellular degeneration and necrosis, focal neuronal degeneration in brain and extramedullary haemopoiesis in spleen. H. hypnale venom caused all above histopathological alterations at lower doses compared to the other two. Conclusion Hypnale venoms cause similar pathological changes with marked differences in the severity of the toxic effects in vivo. Therefore, differences in the severity of the clinical manifestations could possibly be seen among bite victims of the three Hypnale species.

  14. Canopy Venom: Proteomic Comparison among New World Arboreal Pit-Viper Venoms.

    Science.gov (United States)

    Debono, Jordan; Cochran, Chip; Kuruppu, Sanjaya; Nouwens, Amanda; Rajapakse, Niwanthi W; Kawasaki, Minami; Wood, Kelly; Dobson, James; Baumann, Kate; Jouiaei, Mahdokht; Jackson, Timothy N W; Koludarov, Ivan; Low, Dolyce; Ali, Syed A; Smith, A Ian; Barnes, Andrew; Fry, Bryan G

    2016-07-08

    Central and South American pitvipers, belonging to the genera Bothrops and Bothriechis, have independently evolved arboreal tendencies. Little is known regarding the composition and activity of their venoms. In order to close this knowledge gap, venom proteomics and toxin activity of species of Bothriechis, and Bothrops (including Bothriopsis) were investigated through established analytical methods. A combination of proteomics and bioactivity techniques was used to demonstrate a similar diversification of venom composition between large and small species within Bothriechis and Bothriopsis. Increasing our understanding of the evolution of complex venom cocktails may facilitate future biodiscoveries.

  15. Canopy Venom: Proteomic Comparison among New World Arboreal Pit-Viper Venoms

    Directory of Open Access Journals (Sweden)

    Jordan Debono

    2016-07-01

    Full Text Available Central and South American pitvipers, belonging to the genera Bothrops and Bothriechis, have independently evolved arboreal tendencies. Little is known regarding the composition and activity of their venoms. In order to close this knowledge gap, venom proteomics and toxin activity of species of Bothriechis, and Bothrops (including Bothriopsis were investigated through established analytical methods. A combination of proteomics and bioactivity techniques was used to demonstrate a similar diversification of venom composition between large and small species within Bothriechis and Bothriopsis. Increasing our understanding of the evolution of complex venom cocktails may facilitate future biodiscoveries.

  16. Molecular cloning, expression and characterization of albolamin: a type P-IIa snake venom metalloproteinase from green pit viper (Cryptelytrops albolabris).

    Science.gov (United States)

    Jangprasert, Panchalee; Rojnuckarin, Ponlapat

    2014-03-01

    Snake venom metalloproteinases (SVMPs) can damage vessel wall, degrade clotting factors, inhibit integrins and block platelet functions. Studying them not only gives us deeper insights in pathogenesis of snakebites, but also potentially yields novel therapeutic agents. Here, we discovered a clone of an RGD-containing SVMP from the green pit viper (Cryptelytrops albolabris) venom gland cDNA library. Sequence analysis revealed that it belonged to the P-IIa subclass of SVMP comprising signal peptide, prodomain, metalloproteinase and disintegrin. Compared with other P-II SVMPs, it contained 2 additional conserved cysteines that were predicted to prevent the release of disintegrin from the metalloproteinase domain in the mature protein. The N-terminal histidine-tagged construct of metalloproteinase and disintegrin domains of albolamin was inserted into the pPICZαA vector and expressed in Pichia pastoris. The recombinant protein molecular weight was approximately 35 kDa on Western blot probed with anti-polyhistidine antibody. The recombinant albolamin could digest human type IV collagen starting within 15 min after incubation. In addition, it dose-dependently inhibited collagen-induced platelet aggregation with the IC50 of 1.8 μM. However, there was no effect on ADP-induced platelet aggregation. Therefore, the inhibition mechanism is probably through blocking collagen receptor(s). Albolamin activities probably contributed to pathology of green pit viper bites. Its disintegrin domain deserves further studies for the potential to be a useful agent affecting platelet functions. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Proteomic and biochemical analyses of short-tailed pit viper (Gloydius brevicaudus) venom: age-related variation and composition-activity correlation.

    Science.gov (United States)

    Gao, Jian-Fang; Wang, Jin; He, Ying; Qu, Yan-Fu; Lin, Long-Hui; Ma, Xiao-Mei; Ji, Xiang

    2014-06-13

    We conducted an in-depth analysis of the proteomic and biochemical profiles of the venom of neonate and adult short-tailed pit vipers (Gloydius brevicaudus). Identified proteins were assigned to a few main toxin families. Disintegrin, phospholipase A2 (PLA2), serine proteinase, cysteine-rich secretory protein, C-type lectin-like protein, l-amino acid oxidase and snake venom metalloproteinase (SVMP) were detected in both venoms, while 5'-nucleotidase was detected only in the adult venom. SVMP was the predominant protein family in both venoms (neonate: 65.7%; adult: 64.4%), followed by PLA2 (neonate: 13.4%; adult: 25.0%). Antivenomic analysis revealed that commercial G. brevicaudus antivenom almost neutralized the chromatographic peaks with medium and high molecular masses in both venoms, but did not completely recognize peaks with low molecular mass. Toxicological and enzymatic activities show remarkable age-related variation in G. brevicaudus venom, probably resulting from variation in venom composition. Our data demonstrate age-related variation across venomics, antivenomics and biochemical profiles of G. brevicaudus venom, and have implications for the management of G. brevicaudus bites, including improving antivenom preparation by combining both venoms. This study investigates the composition and biochemical activity of neonate and adult Gloydius brevicaudus venoms. We found remarkable age-related variation in venom biological activity, likely the result of variation in venom composition. Antivenomics analysis was used to explore difference in neonate and adult G. brevicaudus venoms. Our findings have implications for the diagnosis and clinical management of G. brevicaudus bites, and the design of venom mixtures that will increase the efficacy of commercial antivenom. This article is part of a Special Issue entitled: Proteomics of non-model organisms. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Computerized electrocardiography in American pit bull terrier dogsEletrocardiografia computadorizada em cães da raça American pit bull terrier

    Directory of Open Access Journals (Sweden)

    Mauro José Lahm Cardoso

    2013-10-01

    Full Text Available Electrocardiography (ECG is an essential examination for evaluation of patient with heart disease is great importance the diagnosis of arrhythmias. The examination can determine source f rhythm and frequency depolarization heart, providing information in clinical status myocardium, since deflections P-QRS-T tracing can be altered by disease or physiological factor. With advancement of computer technology, computerized electrocardiography has been used in human medicine as auxiliary diagnostic method and currently is being increasingly used in veterinary medicine. The objectives this study were to study e computerized electrocardiographic parameters in dogs breed American Pit Bull Terrier, comparing them with patterns species. In present study, we evaluated electrocardiographic examinations 42 dogs the breed American Pit Bull clinically healthy, 22 males and 20 females, aged between 1 and 6 years. Sinus rhythm was observed in 57% of dogs showed sinus rhythm and only 26% were wandering pacemaker. The electrocardiographic values obtained from these dogs computerized ECG were within the normal range of species, except the duration of the P wave which had longer than 0.04 seconds in 24% of dogs. We conclude that the dogs of the breed American Pit Bull Terrier have the same electrocardiographic values obtained in other breeds by the computerized method, except for the increase in P-wave duration. A eletrocardiografia (ECG é um exame essencial para avaliação do paciente com doença cardíaca, sendo de grande importância para o diagnóstico das arritmias. O exame pode determinar a origem do ritmo e a freqüência de despolarização do coração, fornecendo informações do estado clínico do miocárdio, uma vez que as deflexões P-QRS-T do traçado podem ser alteradas por uma enfermidade ou fator fisiológico. Com o avanço da informática, a eletrocardiografia computadorizada tem sido utilizada na medicina humana e veterinária como método de

  19. Coal and Open-pit surface mining impacts on American Lands (COAL)

    Science.gov (United States)

    Brown, T. A.; McGibbney, L. J.

    2017-12-01

    Mining is known to cause environmental degradation, but software tools to identify its impacts are lacking. However, remote sensing, spectral reflectance, and geographic data are readily available, and high-performance cloud computing resources exist for scientific research. Coal and Open-pit surface mining impacts on American Lands (COAL) provides a suite of algorithms and documentation to leverage these data and resources to identify evidence of mining and correlate it with environmental impacts over time.COAL was originally developed as a 2016 - 2017 senior capstone collaboration between scientists at the NASA Jet Propulsion Laboratory (JPL) and computer science students at Oregon State University (OSU). The COAL team implemented a free and open-source software library called "pycoal" in the Python programming language which facilitated a case study of the effects of coal mining on water resources. Evidence of acid mine drainage associated with an open-pit coal mine in New Mexico was derived by correlating imaging spectrometer data from the JPL Airborne Visible/InfraRed Imaging Spectrometer - Next Generation (AVIRIS-NG), spectral reflectance data published by the USGS Spectroscopy Laboratory in the USGS Digital Spectral Library 06, and GIS hydrography data published by the USGS National Geospatial Program in The National Map. This case study indicated that the spectral and geospatial algorithms developed by COAL can be used successfully to analyze the environmental impacts of mining activities.Continued development of COAL has been promoted by a Startup allocation award of high-performance computing resources from the Extreme Science and Engineering Discovery Environment (XSEDE). These resources allow the team to undertake further benchmarking, evaluation, and experimentation using multiple XSEDE resources. The opportunity to use computational infrastructure of this caliber will further enable the development of a science gateway to continue foundational COAL

  20. Trilostane Treatment of Canine Alopecia X in an American Pit Bull Terrier

    Directory of Open Access Journals (Sweden)

    J. Kolevská

    2007-01-01

    Full Text Available This paper describes the case of a one-year-old female American Pit Bull Terrier, presented with the history of progressive baldness. The initial clinical signs were demonstrated by symmetric, primarily non-pruritic alopecia that began in the perineal, genital, and ventral abdominal regions and propagated cranially to the thorax and to the neck. Based on physical and dermatological examination, laboratory findings, and results of skin biopsy, a hormone-responsive dermatosis was diagnosed. Once hypothyroidism and hyperadrenocorticism were ruled out, with the help of hormonal tests, the diagnosis was specified as alopecia X. The first treatment option recommended for the patient and subsequently completed was ovariohysterectomy. After three months, the owner reported improvement; the dog was almost covered with hair. The patient was presented again six months later, showing almost the same dermatological symptoms, which, however, were of a more striking character than before ovariohysterectomy. Again a series of hormonal tests was carried out. Considering the elevated basal and post-adrenocorticothropin stimulation progesterone concentrations, the final aetiology of the disease was determined as an adrenal sex hormone imbalance. Therefore trilostan therapy was initiated. The trilostan dosage of 8 mg/kg/day was divided and given 2 times daily. This treatment led to complete hair regrowth in the dog within four months. No adverse effects associated with trilostane were recognized.

  1. PSEUDO-HERMAFRODITISMO MASCULINO EM CÃO DA RAÇA AMERICAN PIT-BULL TERRIER MASCULINE PSEUDOHERMAPHRODITE IN AMERICAN PIT-BULL TERRIER DOG (A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Luís Paulo Martins Filho

    2007-07-01

    Full Text Available Foi atendido, no Hospital Veterinário-UNESP Jaboticabal, um cão da raça American Pit Bull Terrier, de sete meses de idade, apresentando comportamento sexual masculino exacerbado, apesar de fenótipo feminino. Ao exame clínico e posteriormente cirúrgico, constatou-se a presença de testículos e clitóris peniano. Alguns exames complementares foram realizados como radiografia pélvica e cariótipo, confirmando um caso de pseudo-hermafrodita masculino 78 XY cromossomos. PALAVRAS-CHAVES: American Pit Bull Terrier, cão, pseudo-hermafroditismo. An American Pit Bull Terrier dog was attended to in the Veterinary Hospital- UNESP Jaboticabal. The dog, seven mounths old, presented exagerated masculine beha¬viour, althougth feminine fenotype. Through clinic survey and cirurgical it was confirmed the presence of testis and penile clitoris. Some complements tests were done such as pelvic radiography and cariotype, confirming a case of mas¬culine pseudohermaphrodite with 78 XY cromossomes. KEY-WORDS: Dog, pseudohermaphrodite.

  2. PSEUDO-HERMAFRODITISMO MASCULINO EM CÃO DA RAÇA AMERICAN PIT-BULL TERRIER MASCULINE PSEUDOHERMAPHRODITE IN AMERICAN PIT-BULL TERRIER DOG (A CASE REPORT)

    OpenAIRE

    Luís Paulo Martins Filho; Jeffrey Frederico Lui; Antonio Carlos Alessi; Júlio Carlos Canola; Gilson Hélio Toniollo; Aline Delfini; Valeska Rodrigues

    2007-01-01

    Foi atendido, no Hospital Veterinário-UNESP Jaboticabal, um cão da raça American Pit Bull Terrier, de sete meses de idade, apresentando comportamento sexual masculino exacerbado, apesar de fenótipo feminino. Ao exame clínico e posteriormente cirúrgico, constatou-se a presença de testículos e clitóris peniano. Alguns exames complementares foram realizados como radiografia pélvica e cariótipo, confirmando um caso de pseudo-hermafrodita masculino 78 XY cromossomos. PALAVRAS-CHAVES: Am...

  3. Effect of Trimeresurus albolabris (green pit viper) venom on mean ...

    African Journals Online (AJOL)

    Administrator

    2007-05-02

    May 2, 2007 ... 1Clinical Microscopy Research Unit, Department of Clinical Microscopy, Faculty of Allied Health Sciences,. Chulalongkorn University, Thailand. 2 Snake farm, Thai Red Cross, Thailand. 3Department of Laboratory Medicine, Faculty of Medicine, Chulalongkorn University, Thailand. Accepted 20 April, 2007.

  4. 21 CFR 864.8950 - Russell viper venom reagent.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Russell viper venom reagent. 864.8950 Section 864...) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8950 Russell viper venom reagent. (a) Identification. Russell viper venom reagent is a device used to determine the cause of an...

  5. Pitting corrosion

    International Nuclear Information System (INIS)

    Allgaier, W.

    1985-01-01

    Pitting corrosion is a kind of electrolytic corrosion by which the surface of a material is locally affected owing to inhomogeneities on the part of the material or medium. The paper deals briefly with questions relating to the importance, to parameters medium or materialwise, influence on production and construction, as well as the general conditions for pitting corrosion. In particular oxygen corrosion in unalloyed and low-alloy steel, and pitting corrosion in ferritic chromium-steel and austenitic chromium-nickel (molybdenum) steel is described. (DG) [de

  6. Predator facilitation or interference: a game of vipers and owls.

    Science.gov (United States)

    Embar, Keren; Raveh, Ashael; Hoffmann, Ishai; Kotler, Burt P

    2014-04-01

    In predator-prey foraging games, the prey's reaction to one type of predator may either facilitate or hinder the success of another predator. We ask, do different predator species affect each other's patch selection? If the predators facilitate each other, they should prefer to hunt in the same patch; if they interfere, they should prefer to hunt alone. We performed an experiment in a large outdoor vivarium where we presented barn owls (Tyto alba) with a choice of hunting greater Egyptian gerbils (Gerbillus pyramidum) in patches with or without Saharan horned vipers (Cerastes cerastes). Gerbils foraged on feeding trays set under bushes or in the open. We monitored owl location, activity, and hunting attempts, viper activity and ambush site location, and the foraging behavior of the gerbils in bush and open microhabitats. Owls directed more attacks towards patches with vipers, and vipers were more active in the presence of owls. Owls and vipers facilitated each other's hunting through their combined effect on gerbil behavior, especially on full moon nights when vipers are more active. Owls forced gerbils into the bushes where vipers preferred to ambush, while viper presence chased gerbils into the open where they were exposed to owls. Owls and vipers took advantage of their indirect positive effect on each other. In the foraging game context, they improve each other's patch quality and hunting success.

  7. [Venomous and poisonous animals. II. Viper bites].

    Science.gov (United States)

    Chippaux, J P

    2006-10-01

    Vipers are the main cause of the snake envenomations on all continents except Australia where they are none. Viper envenomation may lead to a minimal inflammatory syndrome with clinical (pain, edema) and biological (hyperleukocytosis, proteinuria) manifestations that may be accompanied by hypotension or shock. Emergency situations are due to hemorrhagic syndrome. In frequent cases in which envenomation is limited to a dramatic decrease in coagulation factors without clinical manifestations, severe local or systemic hemorrhage may occur especially if treatment is delayed. Necrotic complications around the bite or in distant vital organs are not uncommon and require careful medical and surgical surveillance. Intravenous antivenom therapy is the only effective treatment. It should be given as soon as possible but can be effective even when administered several days after the bite.

  8. Acute Renal Failure Following the Saharan Horned Viper (Cerastes ...

    African Journals Online (AJOL)

    Introduction: The Saharan horned viper (Cerastes cerastes) is a common snake in the sandy and rocky regions in the south of Morocco. Although nearly all snakes with medical relevance can induce acute renal failure (ARF), it's unusual except with bites by some viper species. ARF has very rarely been reported following ...

  9. Use of gamma irradiated viper venom as the toxoid against viper venom poisoning in mice and rabbits

    International Nuclear Information System (INIS)

    Hati, A.K.; Mandal, M.; Hati, R.N.; Das, S.

    1995-01-01

    The present paper deals with detoxification of the crude viper (Vipera russelli) venom by gamma irradiation and its effective immunogenic role in Balb/C mice, used as a toxoid. The successful immunization of rabbits with irradiated viper venom toxoid is also reported. Certain biochemical changes of the venom due to radiation exposure and neutralization capacity of the immune sera against phosphodiesterase and protease activity of the crude viper venom have also been studied. The neutralizing potency of Russell's viper venom (RVV) toxoid anti venom (anti venom raised in rabbits against γ-irradiated RVV toxoid adsorbed on aluminium phosphate), in comparison with a commercial bivalent anti venom (as a standard reference) with reference to haemorrhagic, necrotic and lethal effects of Russell's viper envenomation are reported. 25 refs

  10. Genomic and phylogenetic evidence of VIPER retrotransposon domestication in trypanosomatids

    Directory of Open Access Journals (Sweden)

    Adriana Ludwig

    Full Text Available Transposable elements are important residents of eukaryotic genomes and eventually the host can domesticate them to serve cellular functions. We reported here a possible domestication event of the vestigial interposed retroelement (VIPER in trypanosomatids. We found a large gene in a syntenic location in Leishmania braziliensis, L. panamensis, Leptomanas pyrrhocoris, and Crithidia fasciculata whose products share similarity in the C-terminal portion with the third protein of VIPER. No remnants of other VIPER regions surrounding the gene sequence were found. We hypothesise that the domestication event occurred more than 50 mya and the conservation of this gene suggests it might perform some function in the host species.

  11. Evidence-based clinical practice guideline for the use of pit-and-fissure sealants: A report of the American Dental Association and the American Academy of Pediatric Dentistry.

    Science.gov (United States)

    Wright, John T; Crall, James J; Fontana, Margherita; Gillette, E Jane; Nový, Brian B; Dhar, Vineet; Donly, Kevin; Hewlett, Edmond R; Quinonez, Rocio B; Chaffin, Jeffrey; Crespin, Matt; Iafolla, Timothy; Siegal, Mark D; Tampi, Malavika P; Graham, Laurel; Estrich, Cameron; Carrasco-Labra, Alonso

    2016-08-01

    This article presents evidence-based clinical recommendations for the use of pit-and-fissure sealants on the occlusal surfaces of primary and permanent molars in children and adolescents. A guideline panel convened by the American Dental Association (ADA) Council on Scientific Affairs and the American Academy of Pediatric Dentistry conducted a systematic review and formulated recommendations to address clinical questions in relation to the efficacy, retention, and potential side effects of sealants to prevent dental caries; their efficacy compared with fluoride varnishes; and a head-to-head comparison of the different types of sealant material used to prevent caries on pits and fissures of occlusal surfaces. This is an update of the ADA 2008 recommendations on the use of pit-and-fissure sealants on the occlusal surfaces of primary and permanent molars. The authors conducted a systematic search in MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and other sources to identify randomized controlled trials reporting on the effect of sealants (available on the US market) when applied to the occlusal surfaces of primary and permanent molars. The authors used the Grading of Recommendations Assessment, Development, and Evaluation approach to assess the quality of the evidence and to move from the evidence to the decisions. The guideline panel formulated 3 main recommendations. They concluded that sealants are effective in preventing and arresting pit-and-fissure occlusal carious lesions of primary and permanent molars in children and adolescents compared with the nonuse of sealants or use of fluoride varnishes. They also concluded that sealants could minimize the progression of noncavitated occlusal carious lesions (also referred to as initial lesions) that receive a sealant. Finally, based on the available limited evidence, the panel was unable to provide specific recommendations on the relative merits of 1 type of sealant material over the others. These

  12. Optic Nerve Pit

    Science.gov (United States)

    ... Conditions Frequently Asked Questions Español Condiciones Chinese Conditions Optic Nerve Pit What is optic nerve pit? An optic nerve pit is a ... may be seen in both eyes. How is optic pit diagnosed? If the pit is not affecting ...

  13. Antipredatory function of head shape for vipers and their mimics.

    Directory of Open Access Journals (Sweden)

    Janne K Valkonen

    Full Text Available Most research into the adaptive significance of warning signals has focused on the colouration and patterns of prey animals. However, behaviour, odour and body shape can also have signal functions and thereby reduce predators' willingness to attack defended prey. European vipers all have a distinctive triangular head shape; and they are all venomous. Several non-venomous snakes, including the subfamily Natricinae, commonly flatten their heads (also known as head triangulation when disturbed. The adaptive significance of this potential behavioural mimicry has never been investigated.We experimentally tested if the triangular head shape typical of vipers offers protection against predation. We compared the predation pressure of free-ranging predators on artificial snakes with triangular-shaped heads against the pressure on replicas with narrow heads. Snakes of both head types had either zigzag patterned bodies, typical of European vipers, or plain (patternless bodies. Plain snakes with narrower Colubrid-like heads suffered significantly higher predation by raptors than snakes with triangular-shaped heads. Head shape did not, however, have an additive effect on survival in zigzag-patterned snakes, suggesting that species which differ from vipers in colouration and pattern would benefit most from behavioural mimicry. Our results demonstrate that the triangular head shape typical of vipers can act as a warning signal to predators. We suggest that head-shape mimicry may be a more common phenomenon among more diverse taxa than is currently recognised.

  14. Palestine Saw-scaled Vipers hunt disadvantaged avian migrants.

    Science.gov (United States)

    Yosef, Reuven; Zduniak, Piotr

    2015-11-01

    The selection of an ambush-cum-foraging site and proper prey are indispensable for maintaining an adequate energy intake by sit-and-wait predators to optimize survival and future fitness. This is important for snakes, where an ambush site has suitable ambience. We studied the foraging strategy of the Palestine Saw-scaled Viper (Echis coloratus) at an avian migratory stopover site. Following initial observations, we hypothesized that vipers are able to discern the body mass of a perched bird and hunt accordingly. We implemented an experiment where vipers chose between four groups of migratory Blackcaps with different body mass. Prey choice by vipers of both age classes was not random and adults focused on Blackcaps with the lightest body mass. Juveniles displayed a variability of prey choice but selected mainly birds from the lightest categories. We concluded that Saw-scaled Vipers hunt prey based on thermal cues; juveniles practice on different prey groups prior to perfecting their foraging techniques i.e., hunting is a learned process; and that they prefer birds with the lowest body mass. The last because Blackcaps, when on migration, save energy by entering a state of deep torpor in which they sacrifice their vigilance capabilities. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Debunking the viper's strike: harmless snakes kill a common assumption.

    Science.gov (United States)

    Penning, David A; Sawvel, Baxter; Moon, Brad R

    2016-03-01

    To survive, organisms must avoid predation and acquire nutrients and energy. Sensory systems must correctly differentiate between potential predators and prey, and elicit behaviours that adjust distances accordingly. For snakes, strikes can serve both purposes. Vipers are thought to have the fastest strikes among snakes. However, strike performance has been measured in very few species, especially non-vipers. We measured defensive strike performance in harmless Texas ratsnakes and two species of vipers, western cottonmouths and western diamond-backed rattlesnakes, using high-speed video recordings. We show that ratsnake strike performance matches or exceeds that of vipers. In contrast with the literature over the past century, vipers do not represent the pinnacle of strike performance in snakes. Both harmless and venomous snakes can strike with very high accelerations that have two key consequences: the accelerations exceed values that can cause loss of consciousness in other animals, such as the accelerations experienced by jet pilots during extreme manoeuvres, and they make the strikes faster than the sensory and motor responses of mammalian prey and predators. Both harmless and venomous snakes can strike faster than the blink of an eye and often reach a target before it can move. © 2016 The Author(s).

  16. Case report: acute demyelinating encephalomyelitis following viper bite.

    Science.gov (United States)

    Xu, Anyi; Shan, Renfei; Huang, Daochao; Zhou, Jiajia; Keenoo, Anaswasseem; Qin, Jie

    2016-11-01

    The most serious complications of the central nervous system that occur after venomous snake bite are intracranial hemorrhage and ischemic stroke.We present a rarely seen central nervous system complication, acute demyelinating encephalomyelitis, after a treated Deinagkistrodon's viper bite.On April 5, 2015, a 50-year-old male farmer was bitten on his right leg by a Deinagkistrodon's viper. The bite rendered the victim unconscious for 14 days, during which he was treated with tetanus toxoid and polyvalent antisnake venom. Acute demyelinating encephalomyelitis (ADEM) was suspected after magnetic resonance imaging of the brain. After a high dose of methylprednisolone was used as diagnostic treatment, the patient started recovering fast.ADEM is a rare complication after snake bite, and is triggered by venom or antivenin. Magnetic resonance imaging helps in the early diagnosis of ADEM, and high-dose corticosteroid therapy appears to be effective in ADEM after viper bite or antivenin management.

  17. Pit Water Storage Ottrupgaard

    DEFF Research Database (Denmark)

    Heller, Alfred

    2000-01-01

    The pit water storage, a seasonal thermal storage, was built in 1993 with floating lid and hybrid clay-polymer for pit lining. The storage was leaking severe and solutions were to be found. In the paper solutions for pit lining and floating lids are discussed, cost estimations given and coming...

  18. Isolation of a Toxin from Venom of Wagler’s Pit Viper Trimeresurus wagleri

    Science.gov (United States)

    1990-01-31

    activity was performed following the protocol of MARINETTI (1965). Hemolytic activity was assayed by using rat erythrocytes accoding to the method of...activity ( MARINETTI , 1965) detected weak PLA activity in the Superose 12 lethal pool. Bio-Rex 70 isolation of lethal toxin from Suoerose-12 pool...head of bacteriophage T4. Nature 227, 680-685. MARINETTI , G. V. (1965). The action of phospholipase A on lipoproteins. Biochimie Biophys. Acta .98

  19. A mitochondrial DNA phylogeny of the endangered vipers of the Vipera ursinii complex

    Czech Academy of Sciences Publication Activity Database

    Gvoždík, Václav; Jandzik, D.; Cordos, B.; Řehák, I.; Kotlík, Petr

    2012-01-01

    Roč. 62, č. 3 (2012), s. 1019-1024 ISSN 1055-7903 R&D Projects: GA MŠk LC06073 Institutional research plan: CEZ:AV0Z50450515 Keywords : Conservation * Meadow viper * Phylogeny * Steppe viper * Systematics * Vipera ursinii complex Subject RIV: EH - Ecology, Behaviour Impact factor: 4.066, year: 2012

  20. Etch pits on caprolactam

    Science.gov (United States)

    van der Heijden, A. E. D. M.; Geertman, R. M.

    1992-09-01

    As an extension of the results on the morphology, we investigated the defect structure of solution-grown caprolactam crystals by means of slight etching in cyclohexane and subsequent microscopic observation of the resulting etch pits on the 200, 110, and faces. In case of the face (which is a cleavage plane), we confirmed that the etch pits are formed around dislocation lines by performing an "etch-and-match" experiment. Information is obtained on morphology and density of etch pits, the presence of grain boundaries, as well as qualitative information on the inclination of the dislocation lines.

  1. Structure of sump pit

    International Nuclear Information System (INIS)

    Goto, Kaneo; Takahashi, Yukichi; Suzuki, Kunihiko.

    1978-01-01

    Purpose: To provide a sump pit of a structure wherein the leaks of liquid wastes or underwater out of a sump pit storing radioactive liquid wastes can be readily detected. Constitution: A concrete pit is provided with a gap, in which a protective vessel is housed and installed. Furthermore, the protective vessel is provided at its inner side with a gap, in which a liquid waste storage container is installed. In the gap between the liquid waste storage container and the protective vessel there is provided a liquid waste leak detecting electrode. In a case where storage fails due to earthquake, corrosion or the like and the liquid wastes leak, the leak detecting electrode comes into contact with the liquid wastes, and detects the leak thereof. Furthermore, a detecting tube is installed in the gap between the concrete pit and the protective vessel thereby detecting the ingress of underwater. (Kamimura, M.)

  2. PIT Coating Requirements Analysis

    Energy Technology Data Exchange (ETDEWEB)

    MINTEER, D.J.

    2000-10-20

    This study identifies the applicable requirements for procurement and installation of a coating intended for tank farm valve and pump pit interior surfaces. These requirements are intended to be incorporated into project specification documents and design media. This study also evaluates previously recommended coatings and identifies requirement-compliant coating products.

  3. PIT Coating Requirements Analysis

    International Nuclear Information System (INIS)

    MINTEER, D.J.

    2000-01-01

    This study identifies the applicable requirements for procurement and installation of a coating intended for tank farm valve and pump pit interior surfaces. These requirements are intended to be incorporated into project specification documents and design media. This study also evaluates previously recommended coatings and identifies requirement-compliant coating products

  4. Effects of Tamarind (Tamarindus indicus Linn) seed extract on Russell's viper (Daboia russelli siamensis) venom.

    Science.gov (United States)

    Maung, K M; Lynn, Z

    2012-12-01

    Snake bite has been regarded as an important health problem in Myanmar since early 1960's. In the recent years, there has been growing interest in alternative therapies and therapeutic use of natural products, especially those derive from plants. In Myanmar and Indian traditional medicine, various plants have used as a remedy for treating snake bite. The present study was carried out to evaluate the effects of alcohol extract of Tamarind (Tamarindus indica Linn.) seed on some biologic properties of Russell's viper (Daboia russelli siamensis) venom (RVV). The Phospholipase A2 (PLA2) enzyme, coagulase enzyme and caseinolytic enzyme activities of Russell's viper venom (RVV) were reduced when mixed and incubated with the extract. When the RVV and the different amount of extracts were preincubated and injected intramuscularly into mice, all of them survived, but all the mice in the control group died. On the other hand, when RVV were injected first followed by the extract into mice, all of them died. If the extract was injected near the site where Russell's viper venom was injected, all the mice survived for more than 24 hours and the survival time prolonged but they all died within 96 hours. In conclusion, according to the results obtained, the extract neutralizes some biologic properties of the Russell's viper venom and prolonged the survival time if the extract was injected near the site where the Russell's viper venom was injected.

  5. Pitting process visualization

    Directory of Open Access Journals (Sweden)

    Michal Černý

    2010-01-01

    Full Text Available The paper describes time-domain simulation of gear pitting damage using animation program. Key frames have been used to create illusion of motion. The animation uses experimental results of high-cycle fatigue of material. The fatigue damage occurs in the nominal creep area on the side of the gear tooth sample loaded with variable-positioned Hertz pressure. By applying the force, the pressure cumulates between two convex surfaces. This phenomenon results in material damage under of curved surfaces in contact. Moreover, further damage has been registered on the surface. This is due to exceeding the elastic-plastic state limit and development of „tabs“. The tabs serve as origin of surface micro cracks powered by shear stress and enclosed grease pressure as well. This deformation and extreme pressures of Pascal law contribute to elongation and growth of the surface micro crack. Non-homogenous parts of material volume support the initialization/development of the micro cracks as well. Resulting visualization of the tooth-side fatigue damage provides clear and easy-to-understand description of the damage development process right from the micro crack initialization to the final fragmentation due to pitting degradation.

  6. pitting corrosion susceptibility pitting corrosion susceptibility of aisi ...

    African Journals Online (AJOL)

    eobe

    The susceptibility of austenitic (AISI 301) stainless steel to pitting corrosion was evaluated in sodium chloride ... halides, the most aggressive and thus, the most frequently investigated is the chloride ions, particularly its effect on pit formation in 18/8 stainless steel [1 - 3]. ... in sea water), and moderately high temperatures.

  7. PIT Tagging Anurans

    Science.gov (United States)

    McCreary, Brome

    2008-01-01

    The following video demonstrates a procedure to insert a passive integrated transponder (PIT) tag under the skin of an anuran (frog or toad) for research and monitoring purposes. Typically, a 12.5 mm tag (0.5 in.) is used to uniquely identify individual anurans as smal as 40 mm (1.6 in.) in length from snout to vent. Smaller tags are also available and allow smaller anurans to be tagged. The procedure does not differ for other sizes of tages or other sizes of anurans. Anyone using this procedure should ensure that the tag is small enough to fit easily behind the sacral hump of the anuran, as shown in this video.

  8. Power to the pits

    Energy Technology Data Exchange (ETDEWEB)

    Jurbin, T.

    2009-02-15

    This article discussed the need to provide transmission lines to new mines in British Columbia. Commodity pricing and energy use are topical issues in the mining industry, where the viability of a mine may depend on whether it can get electricity from the power grid. There is much incentive to switch from diesel to electricity where possible to reduce fuel consumption and avoid a carbon tax. Less than 0.03 per cent of the land base in British Columbia is used for mining, but 7 mines in BC consume 14 to 17 per cent of all power generated by BC Hydro. The large open pit mines need up to 930 GWh of electricity per year. This article listed some of the hard rock mines that are among the biggest energy users in the province. In general, one sixth of a mine's operating costs is in power consumption. The initial operation of the open pit process involves drilling, blasting, the use of large electric scoop shovels, and water pumping. While trucking is powered by diesel, some mines operate conveyors which increase the amount of electricity used to get ore to the mill. Large electric motors are used in the crushing process. The largest proportion of energy is used in the grinding circuit of the size reduction process. Electricity is also needed for the flotation process and pumping of tailings ponds. Mines dealing with BC Hydro require continuous reliable electricity delivered at a stable voltage . Even a short interruption of a millisecond outage can have a big impact on a mining operation. BC Hydro tries to align its maintenance and repair schedules with the needs of their customer's planned maintenance shut downs as much as possible. 5 figs.

  9. Individual Growth Rates of Nikolsky’s Viper, Vipera berus nikolskii (Squamata, Viperidae

    Directory of Open Access Journals (Sweden)

    Bondarenko Z. S.

    2016-02-01

    Full Text Available Capture-mark-recapture data was used to infer growth rates of the Nikolsky’s viper, Vipera berus nikolskii (Vedmederja, Grubant et Rudaeva, 1986, in the Eastern Ukraine. We have found that growth rate is negatively correlated with age. The difference in growth rates before maturation is not significant between different sexes. Growth rates decrease rapidly after maturation in males and females, however adult males retain significantly higher average growth rates. There is large dispersion of growth rates in the group of adult females, which is caused, probably, by alteration of complete arrest of growth in the years with reproduction and more intensive growth in the years without it. Asymptotic snout-ventral length estimated after Von Bertalanffy model was 680 mm in females and 630 mm in males. Females mature after fifth and males mature after fourth hibernation. The larger females in vipers can not be the result of higher growth rates in females, but are the outcome of a combination of other factors including different maturation time and size (older and being larger, and, perhaps, longer life span due to lower mortality. Growth rates of the Nikolsky’s viper in the nature are higher than in other species in the group of small Eurasian vipers.

  10. Venom Concentrations and Clotting Factor Levels in a Prospective Cohort of Russell's Viper Bites with Coagulopathy.

    Directory of Open Access Journals (Sweden)

    Geoffrey K Isbister

    Full Text Available Russell's viper envenoming is a major problem in South Asia and causes venom induced consumption coagulopathy. This study aimed to investigate the kinetics and dynamics of venom and clotting function in Russell's viper envenoming.In a prospective cohort of 146 patients with Russell's viper envenoming, we measured venom concentrations, international normalised ratio [INR], prothrombin time (PT, activated partial thromboplastin time (aPTT, coagulation factors I, II, V, VII, VIII, IX and X, and von Willebrand factor antigen. The median age was 39 y (16-82 y and 111 were male. The median peak INR was 6.8 (interquartile range [IQR]: 3.7 to >13, associated with low fibrinogen [median,3 at 6 h post-antivenom but had reduced to <2, by 24 h. The aPTT had also returned to close to normal (<50 sec at 24 h. Factor VII, VIII and IX levels were unusually high pre-antivenom, median peak concentrations of 393%, 307% and 468% respectively. Pre-antivenom venom concentrations and the INR (r = 0.20, p = 0.02 and aPTT (r = 0.19, p = 0.03 were correlated (non-parametric Spearman analysis.Russell's viper coagulopathy results in prolonged aPTT, INR, low fibrinogen, factors V, VIII and X which recover over 48 h. Severity of clotting abnormalities was associated with venom concentrations.

  11. VIPER: a web application for rapid expert review of variant calls.

    Science.gov (United States)

    Wöste, Marius; Dugas, Martin

    2018-01-15

    With the rapid development in next-generation sequencing, cost and time requirements for genomic sequencing are decreasing, enabling applications in many areas such as cancer research. Many tools have been developed to analyze genomic variation ranging from single nucleotide variants to whole chromosomal aberrations. As sequencing throughput increases, the number of variants called by such tools also grows. Often employed manual inspection of such calls is thus becoming a time-consuming procedure. We developed the Variant InsPector and Expert Rating tool (VIPER) to speed up this process by integrating the Integrative Genomics Viewer into a web application. Analysts can then quickly iterate through variants, apply filters and make decisions based on the generated images and variant metadata. VIPER was successfully employed in analyses with manual inspection of more than 10,000 calls. VIPER is implemented in Java and Javascript and is freely available at https://github.com/MarWoes/viper. Marius.Woeste@uni-muenster.de. Supplementary data are available at Bioinformatics online. © The Author (2018). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  12. The VIMOS Public Extragalactic Redshift Survey (VIPERS). Full spectroscopic data and auxiliary information release (PDR-2)

    Science.gov (United States)

    Scodeggio, M.; Guzzo, L.; Garilli, B.; Granett, B. R.; Bolzonella, M.; de la Torre, S.; Abbas, U.; Adami, C.; Arnouts, S.; Bottini, D.; Cappi, A.; Coupon, J.; Cucciati, O.; Davidzon, I.; Franzetti, P.; Fritz, A.; Iovino, A.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; Marchetti, A.; Marulli, F.; Polletta, M.; Pollo, A.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Bel, J.; Branchini, E.; De Lucia, G.; Ilbert, O.; McCracken, H. J.; Moutard, T.; Peacock, J. A.; Zamorani, G.; Burden, A.; Fumana, M.; Jullo, E.; Marinoni, C.; Mellier, Y.; Moscardini, L.; Percival, W. J.

    2018-01-01

    We present the full public data release (PDR-2) of the VIMOS Public Extragalactic Redshift Survey (VIPERS), performed at the ESO VLT. We release redshifts, spectra, CFHTLS magnitudes and ancillary information (as masks and weights) for a complete sample of 86 775 galaxies (plus 4732 other objects, including stars and serendipitous galaxies); we also include their full photometrically-selected parent catalogue. The sample is magnitude limited to iAB ≤ 22.5, with an additional colour-colour pre-selection devised as to exclude galaxies at z performed through a fully automated pipeline; all redshift determinations were then visually validated and assigned a quality flag. Measurements with a quality flag ≥ 2 are shown to have a confidence level of 96% or larger and make up 88% of all measured galaxy redshifts (76 552 out of 86 775), constituting the VIPERS prime catalogue for statistical investigations. For this sample the rms redshift error, estimated using repeated measurements of about 3000 galaxies, is found to be σz = 0.00054(1 + z). All data are available at http://vipers.inaf.it and on the ESO Archive. Based on observations collected at the European Southern Observatory, Cerro Paranal, Chile, using the Very Large Telescope under programmes 182.A-0886 and partly 070.A-9007. Also based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT), which is operated by the National Research Council (NRC) of Canada, the Institut National des Sciences de l'Univers of the Centre National de la Recherche Scientifique (CNRS) of France, and the University of Hawaii. This work is based in part on data products produced at TERAPIX and the Canadian Astronomy Data Centre as part of the Canada-France-Hawaii Telescope Legacy Survey, a collaborative project of NRC and CNRS. The VIPERS web site is http://www.vipers.inaf.it/

  13. SEROPREVALENCE AND MOLECULAR CHARACTERIZATION OF FERLAVIRUS IN CAPTIVE VIPERS OF COSTA RICA.

    Science.gov (United States)

    Solis, Cristina; Arguedas, Randall; Baldi, Mario; Piche, Martha; Jimenez, Carlos

    2017-06-01

    Ferlaviruses (FV, previously referred to as ophidian paramyxoviruses, OPMV), are enveloped viruses with a negative-strand RNA genome, affecting snakes in captivity worldwide. Infection is characterized by respiratory and nervous clinical signs and carries high mortality rates, but no specific treatment or vaccine is currently available. Costa Rica has 16 species of vipers, found in captivity in collections essential for antivenom production, reintroduction, and public education. FV circulation in these populations was previously unknown, and the risk of introducing the viruses into naïve collections or free-ranging populations exists if the virus's presence is confirmed. The objective of this study was to determine seroprevalence and FV shedding in 150 samples from captive vipers in nine collections across Costa Rica. A hemagglutination inhibition (HI) assay was performed to determine the antibody titer against two Ferlavirus strains, Bush viper virus (BV) and Neotropical virus (NT), and reverse-transcriptase polymerase chain reaction (RT-PCR) and sequencing to determine virus secretion in cloacal swabs. Ferlavirus strains were replicated in Vero cells, and chicken anti-FV polyclonal antibodies were produced and used as a positive control serum for the HI. Results demonstrate that seroprevalence of anti-FV antibodies in viper serum was 26.6% (n = 40) for the BV strain and 30% (n = 45) for the NT strain in the population tested. Furthermore, molecular characterization of FV group A was possible by sequencing the virus recovered from three cloacal swabs, demonstrating circulation of FV in one collection. This study demonstrates for the first time serological evidence of FV exposure and infection in vipers in captivity in Costa Rica, and suggests cross reactivity between antibodies against both strains. Appropriate biosafety measures could prevent the spread of FV between and within collections of reptiles in the country.

  14. 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

  15. Population Pharmacokinetics of an Indian F(ab')2 Snake Antivenom in Patients with Russell's Viper (Daboia russelii) Bites

    OpenAIRE

    Isbister, Geoffrey K.; Maduwage, Kalana; Saiao, Ana; Buckley, Nicholas A.; Jayamanne, Shaluka F.; Seyed, Shahmy; Mohamed, Fahim; Chathuranga, Umesh; Alexandre, Mendes; Abeysinghe, Chandana; Karunathilake, Harinda; Gawarammana, Indika; Lalloo, David; Janaka de Silva, H.

    2015-01-01

    Background\\ud \\ud There is limited information on antivenom pharmacokinetics. This study aimed to investigate the pharmacokinetics of an Indian snake antivenom in humans with Russell’s viper bites.\\ud \\ud Methods/Principal Findings\\ud \\ud Patient data and serial blood samples were collected from patients with Russell’s viper (Daboia russelii) envenoming in Sri Lanka. All patients received Indian F(ab’)2 snake antivenom manufactured by VINS Bioproducts Ltd. Antivenom concentrations were measur...

  16. Stochastic modeling of pitting corrosion: A new model for initiation and growth of multiple corrosion pits

    Energy Technology Data Exchange (ETDEWEB)

    Valor, A. [Facultad de Fisica, Universidad de La Habana, San Lazaro y L, Vedado, 10400 Havana (Cuba); Caleyo, F. [Departamento de Ingenieria, Metalurgica, IPN-ESIQIE, UPALM Edif. 7, Zacatenco, Mexico DF 07738 (Mexico)]. E-mail: fcaleyo@gmail.com; Alfonso, L. [Departamento de Ingenieria, Metalurgica, IPN-ESIQIE, UPALM Edif. 7, Zacatenco, Mexico DF 07738 (Mexico); Rivas, D. [Departamento de Ingenieria, Metalurgica, IPN-ESIQIE, UPALM Edif. 7, Zacatenco, Mexico DF 07738 (Mexico); Hallen, J.M. [Departamento de Ingenieria, Metalurgica, IPN-ESIQIE, UPALM Edif. 7, Zacatenco, Mexico DF 07738 (Mexico)

    2007-02-15

    In this work, a new stochastic model capable of simulating pitting corrosion is developed and validated. Pitting corrosion is modeled as the combination of two stochastic processes: pit initiation and pit growth. Pit generation is modeled as a nonhomogeneous Poisson process, in which induction time for pit initiation is simulated as the realization of a Weibull process. In this way, the exponential and Weibull distributions can be considered as the possible distributions for pit initiation time. Pit growth is simulated using a nonhomogeneous Markov process. Extreme value statistics is used to find the distribution of maximum pit depths resulting from the combination of the initiation and growth processes for multiple pits. The proposed model is validated using several published experiments on pitting corrosion. It is capable of reproducing the experimental observations with higher quality than the stochastic models available in the literature for pitting corrosion.

  17. On the issue of taxonomical status of steppe viper (Vipera renardi in Right-bank Ukraine

    Directory of Open Access Journals (Sweden)

    A. L. Baybuz

    2011-07-01

    Full Text Available Data on morphologic variability of the steppe viper in the Kirovograd region (Right-bank Ukraine are given firstly. Tentative estimation of the similaritylevel of the local population and the populations from the Left-bank Ukraine and the Crimea was carried out using methods of the multivariate statistics. Morphological data in line with the results of mitochondrial DNA analysis show that the population in the Kirovograd region belongs to widespread Eurasian species Vipera renardiand morphologically most close to the original populations of the lowland Crimea, Sivash and Forest-Steppe of the Left-bank Ukraine. This could indicate the complicated history of the Right-bank Ukraine colonization by the steppe viper and possible influence of environmental conditions on the vipers’ morphology

  18. A Rare Case Series of Ischemic Stroke Following Russell’s Viper Snake Bite in India

    Directory of Open Access Journals (Sweden)

    Venkata Krishna Pothukuchi

    2018-01-01

    Full Text Available Snakebite is an important medical problem in India. Among their various manifestations, cerebral complications are uncommonly found in literature. Moreover, Ischemic stroke following snake bite is quite rare. Here we report a case series of two such cases that developed neurological manifestations following Russell’s viper bite. On computerized tomography (CT scan of brain; cerebral infarcts were revealed. Their likely mechanisms are discussed in present study which include disseminated intravascular coagulation, toxin induced vasculitis and endothelial damage.

  19. Resembling a viper: implications of mimicry for conservation of the endangered smooth snake.

    Science.gov (United States)

    Valkonen, Janne K; Mappes, Johanna

    2014-12-01

    The phenomenon of Batesian mimicry, where a palatable animal gains protection against predation by resembling an unpalatable model, has been a core interest of evolutionary biologists for 150 years. An extensive range of studies has focused on revealing mechanistic aspects of mimicry (shared education and generalization of predators) and the evolutionary dynamics of mimicry systems (co-operation vs. conflict) and revealed that protective mimicry is widespread and is important for individual fitness. However, according to our knowledge, there are no case studies where mimicry theories have been applied to conservation of mimetic species. Theoretically, mimicry affects, for example, frequency dependency of predator avoidance learning and human induced mortality. We examined the case of the protected, endangered, nonvenomous smooth snake (Coronella austriaca) that mimics the nonprotected venomous adder (Vipera berus), both of which occur in the Åland archipelago, Finland. To quantify the added predation risk on smooth snakes caused by the rarity of vipers, we calculated risk estimates from experimental data. Resemblance of vipers enhances survival of smooth snakes against bird predation because many predators avoid touching venomous vipers. Mimetic resemblance is however disadvantageous against human predators, who kill venomous vipers and accidentally kill endangered, protected smooth snakes. We found that the effective population size of the adders in Åland is very low relative to its smooth snake mimic (28.93 and 41.35, respectively).Because Batesian mimicry is advantageous for the mimic only if model species exist in sufficiently high numbers, it is likely that the conservation program for smooth snakes will fail if adders continue to be destroyed. Understanding the population consequences of mimetic species may be crucial to the success of endangered species conservation. We suggest that when a Batesian mimic requires protection, conservation planners should

  20. Vibrationally resolved electronic spectra including vibrational pre-excitation: Theory and application to VIPER spectroscopy

    Science.gov (United States)

    von Cosel, Jan; Cerezo, Javier; Kern-Michler, Daniela; Neumann, Carsten; van Wilderen, Luuk J. G. W.; Bredenbeck, Jens; Santoro, Fabrizio; Burghardt, Irene

    2017-10-01

    Vibrationally resolved electronic absorption spectra including the effect of vibrational pre-excitation are computed in order to interpret and predict vibronic transitions that are probed in the Vibrationally Promoted Electronic Resonance (VIPER) experiment [L. J. G. W. van Wilderen et al., Angew. Chem., Int. Ed. 53, 2667 (2014)]. To this end, we employ time-independent and time-dependent methods based on the evaluation of Franck-Condon overlap integrals and Fourier transformation of time-domain wavepacket autocorrelation functions, respectively. The time-independent approach uses a generalized version of the FCclasses method [F. Santoro et al., J. Chem. Phys. 126, 084509 (2007)]. In the time-dependent approach, autocorrelation functions are obtained by wavepacket propagation and by the evaluation of analytic expressions, within the harmonic approximation including Duschinsky rotation effects. For several medium-sized polyatomic systems, it is shown that selective pre-excitation of particular vibrational modes leads to a redshift of the low-frequency edge of the electronic absorption spectrum, which is a prerequisite for the VIPER experiment. This effect is typically most pronounced upon excitation of modes that are significantly displaced during the electronic transition, such as ring distortion modes within an aromatic π-system. Theoretical predictions as to which modes show the strongest VIPER effect are found to be in excellent agreement with experiment.

  1. Snake Venom Metalloproteinases and Their Peptide Inhibitors from Myanmar Russell’s Viper Venom

    Directory of Open Access Journals (Sweden)

    Khin Than Yee

    2016-12-01

    Full Text Available Russell’s viper bites are potentially fatal from severe bleeding, renal failure and capillary leakage. Snake venom metalloproteinases (SVMPs are attributed to these effects. In addition to specific antivenom therapy, endogenous inhibitors from snakes are of interest in studies of new treatment modalities for neutralization of the effect of toxins. Two major snake venom metalloproteinases (SVMPs: RVV-X and Daborhagin were purified from Myanmar Russell’s viper venom using a new purification strategy. Using the Next Generation Sequencing (NGS approach to explore the Myanmar RV venom gland transcriptome, mRNAs of novel tripeptide SVMP inhibitors (SVMPIs were discovered. Two novel endogenous tripeptides, pERW and pEKW were identified and isolated from the crude venom. Both purified SVMPs showed caseinolytic activity. Additionally, RVV-X displayed specific proteolytic activity towards gelatin and Daborhagin showed potent fibrinogenolytic activity. These activities were inhibited by metal chelators. Notably, the synthetic peptide inhibitors, pERW and pEKW, completely inhibit the gelatinolytic and fibrinogenolytic activities of respective SVMPs at 5 mM concentration. These complete inhibitory effects suggest that these tripeptides deserve further study for development of a therapeutic candidate for Russell’s viper envenomation.

  2. VIPER: a visualisation tool for exploring inheritance inconsistencies in genotyped pedigrees.

    Science.gov (United States)

    Paterson, Trevor; Graham, Martin; Kennedy, Jessie; Law, Andy

    2012-01-01

    Pedigree genotype datasets are used for analysing genetic inheritance and to map genetic markers and traits. Such datasets consist of hundreds of related animals genotyped for thousands of genetic markers and invariably contain multiple errors in both the pedigree structure and in the associated individual genotype data. These errors manifest as apparent inheritance inconsistencies in the pedigree, and invalidate analyses of marker inheritance patterns across the dataset. Cleaning raw datasets of bad data points (incorrect pedigree relationships, unreliable marker assays, suspect samples, bad genotype results etc.) requires expert exploration of the patterns of exposed inconsistencies in the context of the inheritance pedigree. In order to assist this process we are developing VIPER (Visual Pedigree Explorer), a software tool that integrates an inheritance-checking algorithm with a novel space-efficient pedigree visualisation, so that reported inheritance inconsistencies are overlaid on an interactive, navigable representation of the pedigree structure. This paper describes an evaluation of how VIPER displays the different scales and types of dataset that occur experimentally, with a description of how VIPER's display interface and functionality meet the challenges presented by such data. We examine a range of possible error types found in real and simulated pedigree genotype datasets, demonstrating how these errors are exposed and explored using the VIPER interface and we evaluate the utility and usability of the interface to the domain expert.Evaluation was performed as a two stage process with the assistance of domain experts (geneticists). The initial evaluation drove the iterative implementation of further features in the software prototype, as required by the users, prior to a final functional evaluation of the pedigree display for exploring the various error types, data scales and structures. The VIPER display was shown to effectively expose the range of

  3. Clinical and Pharmacological Investigation of Myotoxicity in Sri Lankan Russell's Viper (Daboia russelii Envenoming.

    Directory of Open Access Journals (Sweden)

    Anjana Silva

    2016-12-01

    Full Text Available Sri Lankan Russell's viper (Daboia russelii envenoming is reported to cause myotoxicity and neurotoxicity, which are different to the effects of envenoming by most other populations of Russell's vipers. This study aimed to investigate evidence of myotoxicity in Russell's viper envenoming, response to antivenom and the toxins responsible for myotoxicity.Clinical features of myotoxicity were assessed in authenticated Russell's viper bite patients admitted to a Sri Lankan teaching hospital. Toxins were isolated using high-performance liquid chromatography. In-vitro myotoxicity of the venom and toxins was investigated in chick biventer nerve-muscle preparations. Of 245 enrolled patients, 177 (72.2% had local myalgia and 173 (70.6% had local muscle tenderness. Generalized myalgia and muscle tenderness were present in 35 (14.2% and 29 (11.8% patients, respectively. Thirty-seven patients had high (>300 U/l serum creatine kinase (CK concentrations in samples 24h post-bite (median: 666 U/l; maximum: 1066 U/l. Peak venom and 24h CK concentrations were not associated (Spearman's correlation; p = 0.48. The 24h CK concentrations differed in patients without myotoxicity (median 58 U/l, compared to those with local (137 U/l and generalised signs/symptoms of myotoxicity (107 U/l; p = 0.049. Venom caused concentration-dependent inhibition of direct twitches in the chick biventer cervicis nerve-muscle preparation, without completely abolishing direct twitches after 3 h even at 80 μg/ml. Indian polyvalent antivenom did not prevent in-vitro myotoxicity at recommended concentrations. Two phospholipase A2 toxins with molecular weights of 13kDa, U1-viperitoxin-Dr1a (19.2% of venom and U1-viperitoxin-Dr1b (22.7% of venom, concentration dependently inhibited direct twitches in the chick biventer cervicis nerve-muscle preparation. At 3 μM, U1-viperitoxin-Dr1a abolished twitches, while U1-viperitoxin-Dr1b caused 70% inhibition of twitch force after 3h. Removal of both

  4. On a meeting between the Horn Viper and a Centipede in the Peloponnese, southern Greece  or the Biter, bit

    DEFF Research Database (Denmark)

    Tan, Kit; Kretzschmar, Horst

    2009-01-01

    Vipera ammodytes L., (the European Horn-Nosed Viper) is a small venomous snake occurring in southern L., (the European Horn-Nosed Viper) is a small venomous snake occurring in southern Europe. It was documented attacking Scolopendra cingulata Latreille (the venomous Mediterranean Banded Centipede...

  5. The VIMOS Public Extragalactic Redshift Survey (VIPERS). The decline of cosmic star formation: quenching, mass, and environment connections

    Science.gov (United States)

    Cucciati, O.; Davidzon, I.; Bolzonella, M.; Granett, B. R.; De Lucia, G.; Branchini, E.; Zamorani, G.; Iovino, A.; Garilli, B.; Guzzo, L.; Scodeggio, M.; de la Torre, S.; Abbas, U.; Adami, C.; Arnouts, S.; Bottini, D.; Cappi, A.; Franzetti, P.; Fritz, A.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; Marulli, F.; Moutard, T.; Polletta, M.; Pollo, A.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Bel, J.; Blaizot, J.; Coupon, J.; Hawken, A.; Ilbert, O.; Moscardini, L.; Peacock, J. A.; Gargiulo, A.

    2017-06-01

    We use the final data of the VIMOS Public Extragalactic Redshift Survey (VIPERS) to investigate the effect of the environment on the evolution of galaxies between z = 0.5 and z = 0.9. We characterise local environment in terms of the density contrast smoothed over a cylindrical kernel, the scale of which is defined by the distance to the fifth nearest neighbour. This is performed by using a volume-limited sub-sample of galaxies complete up to z = 0.9, but allows us to attach a value of local density to all galaxies in the full VIPERS magnitude-limited sample to I web site is http://www.vipers.inaf.it/

  6. Sealants for preventing and arresting pit-and-fissure occlusal caries in primary and permanent molars: A systematic review of randomized controlled trials-a report of the American Dental Association and the American Academy of Pediatric Dentistry.

    Science.gov (United States)

    Wright, John T; Tampi, Malavika P; Graham, Laurel; Estrich, Cameron; Crall, James J; Fontana, Margherita; Gillette, E Jane; Nový, Brian B; Dhar, Vineet; Donly, Kevin; Hewlett, Edmond R; Quinonez, Rocio B; Chaffin, Jeffrey; Crespin, Matt; Iafolla, Timothy; Siegal, Mark D; Carrasco-Labra, Alonso

    2016-08-01

    National Health and Nutrition Examination Survey 2011-2012 data indicated that, in the United States, nearly one-fourth of children and over one-half of adolescents experienced dental caries in their permanent teeth. The purpose of this review was to summarize the available clinical evidence regarding the effect of dental sealants for the prevention and management of pit-and-fissure occlusal carious lesions in primary and permanent molars, compared with a control without sealants, with fluoride varnishes, or with other head-to head comparisons. The authors included parallel and split-mouth randomized controlled trials that included at least 2 years of follow-up, which they identified using MEDLINE (via PubMed), Embase, LILACS, the Cochrane Central Register of Controlled Trials, and registers of ongoing trials. Pairs of reviewers independently conducted the selection of studies, data extraction, risk of bias assessments, and quality of the evidence assessments by using the Grading of Recommendations Assessment, Development and Evaluation approach. Of 2,869 records screened, the authors determined that 24 articles (representing 23 studies) proved eligible. Moderate-quality evidence suggested that participants who received sealants had a reduced risk of developing carious lesions in occlusal surfaces of permanent molars compared with those who did not receive sealants (odds ratio [OR], 0.15; 95% confidence interval [CI], 0.08-0.27) after 7 or more years of follow-up. When the authors compared studies whose investigators had compared sealants with fluoride varnishes, they found that sealants reduced the incidence of carious lesions after 7 or more years of follow-up (OR, 0.19; 95% CI, 0.07-0.51); however, this finding was supported by low-quality evidence. On the basis of the evidence, the authors could not provide a hierarchy of effectiveness among the studies whose investigators had conducted head-to-head comparisons. The investigators of 2 trials provided

  7. Evolutionary trajectories of snake genes and genomes revealed by comparative analyses of five-pacer viper

    Science.gov (United States)

    Yin, Wei; Wang, Zong-ji; Li, Qi-ye; Lian, Jin-ming; Zhou, Yang; Lu, Bing-zheng; Jin, Li-jun; Qiu, Peng-xin; Zhang, Pei; Zhu, Wen-bo; Wen, Bo; Huang, Yi-jun; Lin, Zhi-long; Qiu, Bi-tao; Su, Xing-wen; Yang, Huan-ming; Zhang, Guo-jie; Yan, Guang-mei; Zhou, Qi

    2016-01-01

    Snakes have numerous features distinctive from other tetrapods and a rich history of genome evolution that is still obscure. Here, we report the high-quality genome of the five-pacer viper, Deinagkistrodon acutus, and comparative analyses with other representative snake and lizard genomes. We map the evolutionary trajectories of transposable elements (TEs), developmental genes and sex chromosomes onto the snake phylogeny. TEs exhibit dynamic lineage-specific expansion, and many viper TEs show brain-specific gene expression along with their nearby genes. We detect signatures of adaptive evolution in olfactory, venom and thermal-sensing genes and also functional degeneration of genes associated with vision and hearing. Lineage-specific relaxation of functional constraints on respective Hox and Tbx limb-patterning genes supports fossil evidence for a successive loss of forelimbs then hindlimbs during snake evolution. Finally, we infer that the ZW sex chromosome pair had undergone at least three recombination suppression events in the ancestor of advanced snakes. These results altogether forge a framework for our deep understanding into snakes' history of molecular evolution. PMID:27708285

  8. Phosphate (Pi)-regulated heterodimerization of the high-affinity sodium-dependent Pitransporters PiT1/Slc20a1 and PiT2/Slc20a2 underlies extracellular Pisensing independently of Piuptake.

    Science.gov (United States)

    Bon, Nina; Couasnay, Greig; Bourgine, Annabelle; Sourice, Sophie; Beck-Cormier, Sarah; Guicheux, Jérôme; Beck, Laurent

    2018-02-09

    Extracellular phosphate (P i ) can act as a signaling molecule that directly alters gene expression and cellular physiology. The ability of cells or organisms to detect changes in extracellular P i levels implies the existence of a P i -sensing mechanism that signals to the body or individual cell. However, unlike in prokaryotes, yeasts, and plants, the molecular players involved in P i sensing in mammals remain unknown. In this study, we investigated the involvement of the high-affinity, sodium-dependent P i transporters PiT1 and PiT2 in mediating P i signaling in skeletal cells. We found that deletion of PiT1 or PiT2 blunted the P i -dependent ERK1/2-mediated phosphorylation and subsequent gene up-regulation of the mineralization inhibitors matrix Gla protein and osteopontin. This result suggested that both PiTs are necessary for P i signaling. Moreover, the ERK1/2 phosphorylation could be rescued by overexpressing P i transport-deficient PiT mutants. Using cross-linking and bioluminescence resonance energy transfer approaches, we found that PiT1 and PiT2 form high-abundance homodimers and P i -regulated low-abundance heterodimers. Interestingly, in the absence of sodium-dependent P i transport activity, the PiT1-PiT2 heterodimerization was still regulated by extracellular P i levels. Of note, when two putative P i -binding residues, Ser-128 (in PiT1) and Ser-113 (in PiT2), were substituted with alanine, the PiT1-PiT2 heterodimerization was no longer regulated by extracellular P i These observations suggested that P i binding rather than P i uptake may be the key factor in mediating P i signaling through the PiT proteins. Taken together, these results demonstrate that P i -regulated PiT1-PiT2 heterodimerization mediates P i sensing independently of P i uptake. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

  9. Effect of lesion location on fixation strength of the meniscal viper repair system: an in vitro study using porcine menisci.

    Science.gov (United States)

    Chang, Haw Chong; Caborn, David N M; Nyland, John; Burden, Robert

    2006-04-01

    The Meniscal Viper Repair System (Arthrex, Naples, FL) is a novel suture-based all-inside meniscal repair system. This study was performed to test whether the Meniscal Viper Repair System would provide superior fixation characteristics for vertical longitudinal meniscal lesions located closer to the periphery compared with those located further away from the periphery. Vertical longitudinal lesions were created either 1 to 2 mm or 3 to 4 mm away from the periphery of porcine menisci. After repair with the Meniscal Viper Repair System, fixation characteristics were studied during cyclic (500 cycles, 5 to 50 N) and load to failure testing (5 mm/min) in a servo hydraulic device. Meniscal lesion repair location did not show significant differences in displacement or stiffness during cyclic testing. During load to failure testing, meniscal lesion repairs located 1 to 2 mm from the periphery showed superior load at failure (188.8 +/- 45.4 N) compared with repairs located 3 to 4 mm from the periphery (114.4 +/- 35.0 N) (P = .01). Stiffness and displacement during load to failure testing did not show statistically significant differences. The Meniscal Viper Repair System provides stronger meniscal repair strength when lesions are located within 1 to 2 mm of the periphery. The Meniscal Viper Repair System is better suited for repair of peripheral meniscal lesions located within 1 to 2 mm of the periphery. For lesions located in zone 2 (within the central 50%), careful assessment of their distance from the periphery is recommended. For lesions located more than 3 to 4 mm away from the periphery, alternative repair systems or augmentation with other devices may be prudent.

  10. Optimising management of hypertension in primary care: the Valsartan Intensified Primary Care Reduction of Blood Pressure (Viper-Bp) study.

    Science.gov (United States)

    Stewart, Simon; Carrington, Melinda J; Swemmer, Carla; Kurstjens, Nicol; Jennings, Garry L

    2011-12-15

    The Valstartan Intensified Primary CarE Reduction of Blood Pressure Study (VIPER-BP) Study is an open-label, randomised controlled trial comparing usual primary care management with an intensive BP management strategy using three forms of valsartan-based therapy (mono-therapy, thiazide diuretic or calcium channel blocker combinations) to achieve individualised BP control. To identify the features of General Practitioner (GP) management of hypertension in Australia, we analyse the response to a case scenario-based survey of 500 GPs. We subsequently recruited a national cohort of GP Investigators to enrol up to 2500 patients into the VIPER-BP Study. GP responses clearly demonstrated that, compared to the VIPER-BP intervention, a heterogeneous approach to the primary care management of hypertension persists in Australia. By November 2010, 2157 hypertensive patients from 272 actively recruiting GP Investigators were enrolled into the study. Of these, 1965 (91%) patients were entered into a standardised "run-in" phase of 28 days of valsartan 80 mg/day. Subsequently, 1285 patients were randomised to usual care (n=435) or the VIPER-BP intervention (n=850). There was a predominance of males (62%), whilst 55% had pre-existing diabetes or cardiovascular disease and 63% had been previously treated for hypertension. Mean systolic and diastolic BP on randomisation for men and women, respectively, was 148 ± 15/88 ± 11 and 148 ± 18/87 ± 10 mm Hg. In contrast to typical primary care management of hypertension, VIPER-BP combines more intensive and aggressive therapies with structured management to more rapidly attain and sustain individualised BP targets in hypertensive patients. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  11. Speed, Acceleration, Chameleons and Cherry Pit Projectiles

    Science.gov (United States)

    Planinsic, Gorazd; Likar, Andrej

    2012-01-01

    The paper describes the mechanics of cherry pit projectiles and ends with showing the similarity between cherry pit launching and chameleon tongue projecting mechanisms. The whole story is written as an investigation, following steps that resemble those typically taken by scientists and can therefore serve as an illustration of scientific…

  12. Aseismic structure evaluation tests on storage pit

    International Nuclear Information System (INIS)

    Uchida, Seiichi; Fuke, Hikaru; Shimosaka, Shigeru; Kitamura, Katsuhide; Zako, Masaru.

    1984-01-01

    To evaluate the aseismic structural property of a storage pit for vitrified radioactive waste canisters, a full-scale model of the storage pit and canisters filled with dummy vitrified waste were subjected to seismic tests on the shaking table owned by the National Research Center for Disaster Prevention. Three storage pits were tested, all measuring 558.8 mm in diameterx6765 mm in height, of Sch. 40 structural steel plate but with longitudinal internal ribs of different sizes to leave different clearances between the pit and the canister. The dummy canisters, each measuring 430 mm in diameterx1345 mm in height and weighting 480 kg, were piled five high in the pit. The table was shaken in horizontal direction, applying as exciting wave (a) wave pulse, (b) sinusoidal waves in frequency sweep, (c) continuous single-frequency wave and (d) reproduced actual seismic waves. (author)

  13. Floating Lid Constructions for Pit Water Storage

    DEFF Research Database (Denmark)

    Heller, Alfred

    1997-01-01

    Seasonal storage is necessary if renewable heat sources are to be applied on a large scale. Pit water storage seems to be a cheaper alternative to steel tank storage. The lid price is the largest component of a pit water store with a cost share of about 60% of the total storage cost. Due to the l...... to the large share in price the development of lid constructions is crucial for the development of pit water storage and seasonal storage.The current report gives a survey of the most important established and planned designs from Denmark, Sweden and Germany.......Seasonal storage is necessary if renewable heat sources are to be applied on a large scale. Pit water storage seems to be a cheaper alternative to steel tank storage. The lid price is the largest component of a pit water store with a cost share of about 60% of the total storage cost. Due...

  14. Is Playing in the Pit Really the Pits?: Pain, Strength, Music Performance Anxiety, and Workplace Satisfaction in Professional Musicians in Stage, Pit, and Combined Stage/Pit Orchestras.

    Science.gov (United States)

    Kenny, Dianna T; Driscoll, Tim; Ackermann, Bronwen J

    2016-03-01

    Typically, Australian orchestral musicians perform on stage, in an orchestra pit, or in a combination of both workplaces. This study explored a range of physical and mental health indicators in musicians who played in these different orchestra types to ascertain whether orchestra environment was a risk factor affecting musician wellbeing. Participants comprised 380 full-time orchestral musicians from the eight major state orchestras in Australia comprised of two dedicated pit orchestras, three stage-only symphonic orchestras, and three mixed stage/pit orchestras. Participants completed a physical assessment and a range of self-report measures assessing performance-related musculoskeletal disorders (PRMD), physical characteristics including strength and perceived exertion, and psychological health, including music performance anxiety (MPA), workplace satisfaction, and bullying. Physical characteristics and performance-related musculoskeletal profiles were similar for most factors on the detailed survey completed by orchestra members. The exceptions were that pit musicians demonstrated greater shoulder and elbow strength, while mixed-workload orchestra musicians had greater flexibility Significantly more exertion was reported by pit musicians when rehearsing and performing. Stage/pit musicians reported less physical exertion when performing in the pit compared with performing on stage. Severity of MPA was significantly greater in pit musicians than mixed orchestra musicians. Pit musicians also reported more frequent bullying and lower job satisfaction compared with stage musicians. There were few differences in the objective physical measures between musicians in the different orchestra types. However, pit musicians appear more psychologically vulnerable and less satisfied with their work than musicians from the other two orchestra types. The physical and psychological characteristics of musicians who perform in different orchestra types have not been adequately

  15. Women miners in developing countries: pit women and others

    Energy Technology Data Exchange (ETDEWEB)

    Kuntala Lahiri-Dutt; Martha Macintyre [Australian National University (Australia). Research School of Pacific and Asian Studies

    2006-05-15

    Contrary to their masculine portrayal, mines have always employed women in valuable and productive roles. Yet, pit life continues to be represented as a masculine world of work, legitimizing men as the only mineworkers and large, mechanized, and capitalized operations as the only form of mining. Bringing together a range of case studies of women miners from past and present in Asia, the Pacific Region, Latin America and Africa, this book makes visible the roles and contributions of women as miners. It also highlights the importance of engendering small and informal mining in the developing world as compared to the early European and American mines. The book shows that women are engaged in various kinds of mining and illustrates how gender and inequality are constructed and sustained in the mines, and also how ethnic identities intersect with those gendered identities. Chapters dealing with coal mining include: Introduction: Where life is in the pits (and elsewhere) and gendered; Japanese coal mining: women discovered; Mining gender at work in the Indian collieries: identity construction; Women in the mining industry of contemporary China; Roti do, ya goli do! (give us bread, or give us bullets!): stories of struggles of women workers in Bhowra colliery, India and Globalization and women's work in the mine pits in East Kalimantan, Indonesia. 17 ills.

  16. Risk factors for high-grade envenomations after French viper bites in children.

    Science.gov (United States)

    Claudet, Isabelle; Maréchal, Céline; Gurrera, Emmanuel; Cordier, Laurie; Honorat, Raphaele; Grouteau, Erick

    2012-07-01

    Viper bites and subsequent evolution to severe envenomations are more frequent in children. The aims of this study were to describe the clinical, biological, and therapeutic characteristics of children bitten by vipers in France and to identify risk factors associated with severe envenomations. A retrospective study was conducted between 2001 and 2009 in the pediatric emergency department of a tertiary-level children hospital. Collected data were age and sex of children; day and time of admission; day, time, and circumstances of the accident; snake identification; bite location; envenomation severity; presence of fang marks; prehospital care; use of specific immunotherapy and associated treatments; length of stay; and hospital course. Fifty-eight children were included (43 boys, 15 girls). The mean age was 7.8 ± 4.1 years. Bites were most often located on the lower extremities (77%). The classification of envenomation was: 83% low grade (absence or minor envenomation) and 17% high-grade (moderate to severe envenomations). All high-grade envenomations received specific immunotherapy (Viperfav). Being bitten on an upper extremity (P level (P = 0.016) were associated with a significant risk of high-grade envenomation. In the multivariate analysis, 3 factors remained significant: upper-extremity location (relative risk [RR], 60.5 [3.5-1040]; P = 0.005), immediate violent pain (RR, 21.5 [1.3-364.5]; P = 0.03), and female sex (RR, 17.5 [0.9-320.3]; P = 0.053). A certain number of criteria seem related to more significant risk of progression to high-grade envenomation. Bites to the upper extremities should be carefully observed because of the risk of evolution to a high-grade envenomation.

  17. Assessing granular pit construction from larval Neuroptera

    Science.gov (United States)

    Shea, Nicholas; Olafsen, Jeffrey S.; Loudon, Catherine; Steeples, Don W.

    2002-03-01

    Antlion larvae, Myrmeleon carolinus, build cone-shaped pits in dry sand for prey capture. The surface of these pits are prone to avalanches that can depend upon the physical properties of the sand in the local environment. The antlion larvae are observed to be capable of assessing both sand depth and particle size. In a polydisperse granular environment, the antlion demonstrates the ability to sort the sand by size in a dynamic manner. An imaging technique is developed to investigate the potential role of air viscosity on the pit construction process.

  18. The cuisine of the Pitted Ware Culture

    DEFF Research Database (Denmark)

    Philippsen, Bente; Persson, Per

    The Pitted Ware Culture is a Middle Neolithic culture in southwestern Scandinavia. It appears about thousand years after the introduction of agriculture to this area. In some regions, it is characterized by an almost fully “Mesolithic” economy with a heavy reliance on seal hunting. In Djursland......, northeastern Denmark, however, the Pitted Ware Culture has always been regarded as having a mixed economy, utilizing both domesticated and wild resources. The research presented here was prepared in the framework of the multi-disciplinary project “CONTACT. The Pitted Ware Phenomenon in Djursland and Maritime...

  19. Pitted keratolysis, erythromycin, and hyperhidrosis.

    Science.gov (United States)

    Pranteda, Guglielmo; Carlesimo, Marta; Pranteda, Giulia; Abruzzese, Claudia; Grimaldi, Miriam; De Micco, Sabrina; Muscianese, Marta; Bottoni, Ugo

    2014-01-01

    Pitted keratolysis (PK) is a plantar skin disorder mainly caused by coryneform bacteria. A common treatment consists of the topical use of erythromycin. Hyperhidrosis is considered a predisposing factor for bacterial proliferation and, consequently, for the onset of PK. The aim of this study was to evaluate the relationship between PK erythromycin and hyperhidrosis. All patients with PK seen in Sant'Andrea Hospital, between January 2009 and December 2011, were collected. PK was clinically and microscopically diagnosed. All patients underwent only topical treatment with erythromycin 3% gel twice daily. At the beginning of the study and after 5 and 10 days of treatment, a clinical evaluation and a gravimetric measurement of plantar sweating were assessed. A total of 97 patients were diagnosed as PK and were included in the study. Gravimetric measurements showed that in 94 of 97 examined patients (96.90%) at the time of the diagnosis, there was a bilateral excessive sweating occurring specifically in the areas affected by PK. After 10 days of antibiotic therapy, hyperhidrosis regressed together with the clinical manifestations. According to these data, we hypothesize that hyperhidrosis is due to an eccrine sweat gland hyperfunction, probably secondary to bacterial infection. © 2013 Wiley Periodicals, Inc.

  20. CHerenkov detectors In mine PitS (CHIPS) Letter of Intent to FNAL

    Energy Technology Data Exchange (ETDEWEB)

    Adamson, P. [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Austin, J. [Univ. of Minnesota, Duluth, MN (United States); Cao, S. V. [Univ. of Texas, Austin, TX (United States); Coelho, J. A. B. [Tufts Univ., Medford, MA (United States); Davies, G. S. [Iowa State Univ., Ames, IA (United States); Evans, J. J. [Univ. of Manchester (United Kingdom); Guzowski, P. [Univ. of Manchester (United Kingdom); Habig, A. [Univ. of Minnesota, Duluth, MN (United States); Holin, A. [Univ. College London, London (United Kingdom); Huang, J. [Univ. of Texas, Austin, TX (United States); Johnson, R. [Univ. of Cincinnati, OH (United States); St. John, J. [Univ. of Cincinnati, OH (United States); Kreymer, A. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Kordosky, M. [College of William and Mary, Williamsburg, VA (United States); Lang, K. [Univ. of Texas, Austin, TX (United States); Marshak, M. L. [Univ. of Minnesota, Minneapolis, MN (United States); Mehdiyev, R. [Univ. of Texas, Austin, TX (United States); Meier, J. [Univ. of Minnesota, Minneapolis, MN (United States); Miller, W. [Univ. of Minnesota, Minneapolis, MN (United States); Naples, D. [Univ. of Pittsburgh, PA (United States); Nelson, J. K. [College of William and Mary, Williamsburg, VA (United States); Nichol, R. J. [Univ. College London, London (United Kingdom); Patterson, R. B. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Paolone, V. [Univ. of Pittsburgh, PA (United States); Pawloski, G. [Univ. of Minnesota, Minneapolis, MN (United States); Perch, A. [Univ. College London, London (United Kingdom); Pfutzner, M. [Univ. College London, London (United Kingdom); Proga, M. [Univ. of Texas, Austin, TX (United States); Qian, X. [Brookhaven National Lab. (BNL), Upton, NY (United States); Radovic, A. [Univ. College London, London (United Kingdom); Sanchez, M. C. [Iowa State Univ., Ames, IA (United States); Schreiner, S. [Univ. of Minnesota, Minneapolis, MN (United States); Soldner-Rembold, S. [Univ. of Manchester (United Kingdom); Sousa, A. [Univ. of Cincinnati, OH (United States); Thomas, J. [Univ. College London, London (United Kingdom); Vahle, P. [College of William and Mary, Williamsburg, VA (United States); Wendt, C. [Univ. of Wisconsin, Madison, WI (United States); Whitehead, L. H. [Univ. College London, London (United Kingdom); Wojcicki, S. [Stanford Univ., CA (United States)

    2013-12-30

    This Letter of Intent outlines a proposal to build a large, yet cost-effective, 100 kton fiducial mass water Cherenkov detector that will initially run in the NuMI beam line. The CHIPS detector (CHerenkov detector In Mine PitS) will be deployed in a flooded mine pit, removing the necessity and expense of a substantial external structure capable of supporting a large detector mass. There are a number of mine pits in northern Minnesota along the NuMI beam that could be used to deploy such a detector. In particular, the Wentworth Pit 2W is at the ideal off-axis angle to contribute to the measurement of the CP violating phase. The detector is designed so that it can be moved to a mine pit in the LBNE beam line once that becomes operational.

  1. AHAR: Part 1 - PIT Estimates of Homelessness

    Data.gov (United States)

    Department of Housing and Urban Development — This report outlines the key findings of the 2014 Point-In-Time (PIT) and Housing Inventory (HIC) counts conducted in January 2014. Specifically, this report...

  2. CLPX-Ground: ISA Snow Pit Measurements

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set consists of snow pit data from nine study areas, within three larger-scale areas in northern Colorado (Fraser, North Park, and Rabbit Ears Meso-cell...

  3. Pitting corrosion of 5052 aluminum alloy

    Science.gov (United States)

    Lockwood, F.; Lee, S.; Faunce, J.; Green, J. A. S.; Ptashnick, W. J.

    1985-01-01

    The relative degree of pitting of 5052 aluminum alloy in a prepaint cleaning process is correlated with the proportion of MgO in the surface oxide of the alloy. Magnesium oxide, formed on the surface during process heat treatments of the alloy, is soluble in the acidic environment of the particular cleaning solutions, thus allowing easier access of corrosive ion to the aluminum metal. The pitting mechanism involves the: (1) formation of microscopic, localized galvanic cells between aluminum (anode) and iron-containing constituents (cathodic sites) normally found in the matrix of 5052 (and other 5xxx aluminum alloys), (2) aggravation of pit formation by chloride, and (3) enhancement of cathodic reactions and hence the overall corrosion process due to penetration of the oxide layer by cupric and ferric ions, and dissolved O 2 present in the cleaning solutions. Pitting was eliminated by adding 0.1% NaNO 3 to the cleaning bath.

  4. THE USE OF THE ANTI-VENOM SPECIFIC ANTIBODIES ISOLATED FROM DUCK EGGS FOR INACTIVATION OF THE VIPER VENOM

    Directory of Open Access Journals (Sweden)

    ADRIANA CRISTE

    2008-05-01

    Full Text Available The activity of specific anti-venom can be demonstrated using protection test in laboratory mice. Our study aimed to emphasize the possibility of viper venom inactivation by the antibodies produced and isolated from duck eggs and also to the activation concentration of these antibodies. The venom used for inoculation was harvested from two viper species (Vipera ammodytes and Vipera berus. The immunoglobulin extract had a better activity on the venom from Vipera berus compared to the venom from Vipera ammodytes. This could be the result of a better immunological response, as consequence of the immunization with this type of venom, compared to the response recorded when the Vipera ammodytes venom was used. Besides the advantages of low cost, high productivity and reduced risk of anaphylactic shock, the duck eggs also have high activity up to dilutions of 1/16, 1/32, respectively, with specific activity and 100 surviving in individuals which received 3 x DL50.

  5. Pit 9 project: A private sector initiative

    International Nuclear Information System (INIS)

    Macdonald, D.W.; Hughes, F.P.; Burton, B.N.

    1993-01-01

    This report discusses the Pit 9 Comprehensive Demonstration which is intended to demonstrate a cost-effective approach to remediate an Idaho National Engineering Laboratory (INEL) waste disposal pit through a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Interim Action. The remediation will include additional requirements, if needed, to provide high confidence that only minor additional work would be necessary to accomplish the final closure as part of the overall final closure strategy for the INEL's Subsurface Disposal Area (SDA)

  6. Sexual dimorphism in development and venom production of the insular threatened pit viper Bothrops insularism (Serpentes: Viperidae of Queimada Grande Island, Brazil

    Directory of Open Access Journals (Sweden)

    S.R. Travaglia-Cardoso

    2010-09-01

    Full Text Available Bothrops insularis is a threatened snake endemic to Queimada Grande Island, southern coast of São Paulo, Brazil, and the occurrence of sexual abnormalities in females (females with functional ovaries and rudimentary hemipenis has been reported in this population. To date there are few data regarding developmental features of this particular species. The aim of this study was to follow some developmental features in specimens maintained in captivity for seven years in the Herpetology Laboratory at Instituto Butantan, São Paulo, Brazil. We verified a pronounced sexual dimorphism in development and venom production in the specimens analyzed. In this regard, females showed greater length, mass and amount of venom in comparison to males. Our results suggest a possible niche partitioning between the sexes that reduces (or minimizes intraspecific disharmonic interactions (eg. competition on their small living area (Queimada Grande Island. Taken together, our data suggest that males and females probably are divergent in their diets, with females feeding preferentially on endothermic prey (such as migratory birds, while males maintain the juvenile diet (with the major items being ectothermic prey.

  7. Detection of venom after antivenom is not associated with persistent coagulopathy in a prospective cohort of Russell's viper (Daboia russelii envenomings.

    Directory of Open Access Journals (Sweden)

    Kalana Maduwage

    2014-12-01

    Full Text Available Venom recurrence or persistence in the circulation after antivenom treatment has been documented many times in viper envenoming. However, it has not been associated with clinical recurrence for many snakes, including Russell's viper (Daboia spp.. We compare the recovery of coagulopathy to the recurrence or persistence of venom in patients with Russell's viper envenoming.The study included patients with Russell's viper (D. russelii envenoming presenting over a 30 month period who had Russell's viper venom detected by enzyme immunoassay. Demographics, information on the snake bite, and clinical effects were collected for all patients. All patients had serum collected for venom specific enzyme immunoassay and citrate plasma to measure fibrinogen levels and prothrombin time (international normalised ratio; INR. Patients with venom recurrence/persistence were compared to those with no detectable recurrence of venom. There were 55 patients with confirmed Russell's viper envenoming and coagulopathy with low fibrinogen concentrations: 31 with venom recurrence/persistence, and 24 with no venom detected post-antivenom. Fibrinogen concentrations increased and INR decreased after antivenom in both the recurrence and non-recurrence patients. Clinical features, laboratory parameters, antivenom dose and length of hospital were similar for both groups. Pre-antivenom venom concentrations were higher in patients with venom recurrence/persistence with a median venom concentration of 385 ng/mL (16-1521 ng/mL compared to 128 ng/mL (14-1492 ng/mL; p = 0.008.Recurrence of Russell's viper venom was not associated with a recurrence of coagulopathy and length of hospital stay. Further work is required to determine if the detection of venom recurrence is due to the venom specific enzyme immunoassay detecting both venom-antivenom complexes as well as free venom.

  8. Pitting of malaria parasites and spherocyte formation

    Directory of Open Access Journals (Sweden)

    Gichuki Charity W

    2006-07-01

    Full Text Available Abstract Background A high prevalence of spherocytes was detected in blood smears of children enrolled in a case control study conducted in the malaria holoendemic Lake Victoria basin. It was speculated that the spherocytes reflect intraerythrocytic removal of malarial parasites with a concurrent removal of RBC membrane through a process analogous to pitting of intraerythrocytic inclusion bodies. Pitting and re-circulation of RBCs devoid of malaria parasites could be a host mechanism for parasite clearance while minimizing the anaemia that would occur were the entire parasitized RBC removed. The prior demonstration of RBCs containing ring-infected erythrocyte surface antigen (pf 155 or RESA but no intracellular parasites, support the idea of pitting. Methods An in vitro model was developed to examine the phenomenon of pitting and spherocyte formation in Plasmodium falciparum infected RBCs (iRBC co-incubated with human macrophages. In vivo application of this model was evaluated using blood specimens from patients attending Kisumu Ditrict Hospital. RBCs were probed with anti-RESA monoclonal antibody and a DNA stain (propidium iodide. Flow cytometry and fluorescent microscopy was used to compare RBCs containing both the antigen and the parasites to those that were only RESA positive. Results Co-incubation of iRBC and tumor necrosis factor-alpha activated macrophages led to pitting (14% ± 1.31% macrophages with engulfed trophozoites as opposed to erythrophagocytosis (5.33% ± 0.95% (P Conclusion It is proposed that in malaria holoendemic areas where prevalence of asexual stage parasites approaches 100% in children, RBCs with pitted parasites are re-circulated and pitting may produce spherocytes.

  9. Baseline Risk Assessment for the F-Area Burning/Rubble Pits and Rubble Pit

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, E. [Westinghouse Savannah River Company, AIKEN, SC (United States)

    1996-03-01

    This document provides an overview of the Savannah River Site (SRS) and a description of the F-Area Burning/Rubble Pits (BRPs) and Rubble Pit (RP) unit. It also describes the objectives and scope of the baseline risk assessment (BRA).

  10. NELL-1 increases pre-osteoblast mineralization using both phosphate transporter Pit1 and Pit2

    International Nuclear Information System (INIS)

    Cowan, Catherine M.; Zhang, Xinli; James, Aaron W.; Mari Kim, T.; Sun, Nichole; Wu, Benjamin; Ting, Kang; Soo, Chia

    2012-01-01

    Highlights: ► NELL-1 accelerates extracellular matrix mineralization in MC3T3-E1 pre-osteoblasts. ► NELL-1 significantly increases intracellular inorganic phosphate levels. ► NELL-1 positively regulates osteogenesis but not proliferation in MC3T3-E1 cells. ► NELL-1 regulates inorganic phosphate transporter activity. -- Abstract: NELL-1 is a potent osteoinductive molecule that enhances bone formation in multiple animal models through currently unidentified pathways. In the present manuscript, we hypothesized that NELL-1 may regulate osteogenic differentiation accompanied by alteration of inorganic phosphate (Pi) entry into the osteoblast via sodium dependent phosphate (NaPi) transporters. To determine this, MC3T3-E1 pre-osteoblasts were cultured in the presence of recombinant human (rh)NELL-1 or rhBMP-2. Analysis was performed for intracellular Pi levels through malachite green staining, Pit-1 and Pit-2 expression, and forced upregulation of Pit-1 and Pit-2. Results showed rhNELL-1 to increase MC3T3-E1 matrix mineralization and Pi influx associated with activation of both Pit-1 and Pit-2 channels, with significantly increased Pit-2 production. In contrast, Pi transport elicited by rhBMP-2 showed to be associated with increased Pit-1 production only. Next, neutralizing antibodies against Pit-1 and Pit-2 completely abrogated the Pi influx effect of rhNELL-1, suggesting rhNELL-1 is dependent on both transporters. These results identify one potential mechanism of action for rhNELL-1 induced osteogenesis and highlight a fundamental difference between NELL-1 and BMP-2 signaling.

  11. NELL-1 increases pre-osteoblast mineralization using both phosphate transporter Pit1 and Pit2

    Energy Technology Data Exchange (ETDEWEB)

    Cowan, Catherine M. [Department of Bioengineering, University of California, Los Angeles, 420 Westwood Plaza,7523 Boelter Hall, Los Angeles, CA 90095 (United States); Dental and Craniofacial Research Institute and Section of Orthodontics, School of Dentistry, University of California, Los Angeles, 40833 Le Conte Ave, Los Angeles, CA 90095 (United States); Zhang, Xinli; James, Aaron W.; Mari Kim, T.; Sun, Nichole [Dental and Craniofacial Research Institute and Section of Orthodontics, School of Dentistry, University of California, Los Angeles, 40833 Le Conte Ave, Los Angeles, CA 90095 (United States); Wu, Benjamin [Department of Bioengineering, University of California, Los Angeles, 420 Westwood Plaza,7523 Boelter Hall, Los Angeles, CA 90095 (United States); Dental and Craniofacial Research Institute and Section of Orthodontics, School of Dentistry, University of California, Los Angeles, 40833 Le Conte Ave, Los Angeles, CA 90095 (United States); Ting, Kang [Dental and Craniofacial Research Institute and Section of Orthodontics, School of Dentistry, University of California, Los Angeles, 40833 Le Conte Ave, Los Angeles, CA 90095 (United States); Soo, Chia, E-mail: bsoo@ucla.edu [UCLA and Orthopaedic Hospital Department of Orthopaedic Surgery and the Orthopaedic, Hospital Research Center, University of California, Los Angeles, 2641 Charles E. Young Dr. South, Los Angeles, CA 90095 (United States)

    2012-06-08

    Highlights: Black-Right-Pointing-Pointer NELL-1 accelerates extracellular matrix mineralization in MC3T3-E1 pre-osteoblasts. Black-Right-Pointing-Pointer NELL-1 significantly increases intracellular inorganic phosphate levels. Black-Right-Pointing-Pointer NELL-1 positively regulates osteogenesis but not proliferation in MC3T3-E1 cells. Black-Right-Pointing-Pointer NELL-1 regulates inorganic phosphate transporter activity. -- Abstract: NELL-1 is a potent osteoinductive molecule that enhances bone formation in multiple animal models through currently unidentified pathways. In the present manuscript, we hypothesized that NELL-1 may regulate osteogenic differentiation accompanied by alteration of inorganic phosphate (Pi) entry into the osteoblast via sodium dependent phosphate (NaPi) transporters. To determine this, MC3T3-E1 pre-osteoblasts were cultured in the presence of recombinant human (rh)NELL-1 or rhBMP-2. Analysis was performed for intracellular Pi levels through malachite green staining, Pit-1 and Pit-2 expression, and forced upregulation of Pit-1 and Pit-2. Results showed rhNELL-1 to increase MC3T3-E1 matrix mineralization and Pi influx associated with activation of both Pit-1 and Pit-2 channels, with significantly increased Pit-2 production. In contrast, Pi transport elicited by rhBMP-2 showed to be associated with increased Pit-1 production only. Next, neutralizing antibodies against Pit-1 and Pit-2 completely abrogated the Pi influx effect of rhNELL-1, suggesting rhNELL-1 is dependent on both transporters. These results identify one potential mechanism of action for rhNELL-1 induced osteogenesis and highlight a fundamental difference between NELL-1 and BMP-2 signaling.

  12. Impact of cool versus warm temperatures on gestation in the aspic viper (Vipera aspis).

    Science.gov (United States)

    Michel, Catherine Louise; Pastore, Jean-Henri; Bonnet, Xavier

    2013-07-01

    Previous experimental data suggested that digestion and growth rates are not impaired under cool constant temperature (23°C) in a viviparous snake (Vipera aspis). These results challenged the widespread notion that both elevated temperatures (e.g. 30°C) and temperature fluctuations are required for digestion and growth in temperate climate reptiles. Here, we investigated the impact of constant cool temperatures on another physiological performance that is crucial to population persistence: gestation. At the time when reproductive females were midway through vitellogenesis, we placed ten reproductive and two non-reproductive female aspic vipers at each of two contrasted constant temperature conditions: cool (23°C) versus warm (28°C). Sixty percent of the females placed at 28°C gave birth to healthy offspring, suggesting that constant warm body temperatures were compatible with normal offspring production. Conversely, none of the cool females gave birth to healthy offspring. A blister disease affected exclusively cool pregnant females. Apparently, the combination of cool temperatures plus gestation was too challenging for such females. Our results suggest that reproduction is more thermally sensitive than digestion or growth, indeed gestation faltered under moderately cool thermal constraints. This sensitivity could be a crucial factor determining the capacity of this species to colonize different habitats. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. The life and viper of Dr Patrick Russell MD FRS (1727-1805): physician and naturalist.

    Science.gov (United States)

    Hawgood, B J

    1994-11-01

    It is nearly two hundred years since the publication in 1796 of An Account of Indian Serpents collected on the Coast of Coromandel by Patrick Russell. Within the folio is a drawing and description of the venomous snake called Katuka Rekula Poda in the local Telugu language, whose venom was shown experimentally by Dr Russell to be nearly as lethal as that of Cobra de Capello. The snake is now known as Vipera russelli or Russell's viper. Dr Russell was representative of the naturalistic tendency of British medicine in the late 18th century. He was a keen observer and skilled doctor in clinical practice, particularly in Aleppo, Syria, during an outbreak of the plague, and indefatigable in his study of plant and animal life both in Aleppo and later in the Madras Province of India. As a physician as well as Naturalist to the East India Company in the Carnatic he was concerned with the problem of snakebite. His first aim was to find a means whereby the non-specialist could distinguish between poisonous and harmless snakes and so combat the terrible notion that all bites were mortal. His writing, encompassing social and natural histories and climaxed by a study of snakes, has left a rich legacy. Dr Patrick Russell was a man of the highest integrity and ability, a physician and naturalist par excellence.

  14. The Distinct Build-Up Of Dense And Normal Massive Passive Galaxies In Vipers

    Science.gov (United States)

    Gargiulo, Adriana; Vipers Team

    2017-06-01

    At fixed stellar mass, the population of passive galaxies has increased its mean effective radius by a factor 5 in the last 10 Gyr, decreasing its mean stellar mass density (S = Mstar/(2πRe 2 ) by a factor >> 10. Whether this increase in is mainly due to the size-growth of individual galaxies through dry mergers, or to the fact that newly quenched galaxies have a larger size, is still matter of debate. A promising approach to shed light on this issue is to investigate the evolution of the number density of passive galaxies as a function of their mass density. In this context, massive (Mstar >10^11 Msun) passive galaxies are the most intriguing systems to study, since, in a hierarchical scenario, they are expected to accrete their stellar mass mainly by mergers. The wide area (˜ 16 sq. deg) and high sampling rate (˜ 40%) of the spectroscopic survey VIPERS allowed us to collect a sample of ˜ 2000 passive massive galaxies over the redshift range 0.5 population of passive galaxies as function both of redshift and mass density. This information, combined with the evolution of the number density allowed us to put constraints on the mass accretion scenarios of passive galaxies. In this talk I will present our results and conclusions and how they depend on the environment in which the galaxies reside.

  15. Climate change and peripheral populations: predictions for a relict Mediterranean viper

    Directory of Open Access Journals (Sweden)

    José C. Brito

    2011-06-01

    Full Text Available Ecological niche-based models were developed in peripheral populations of Vipera latastei North Africa to: 1 identify environmental factors related to species occurrence; 2 identify present suitable areas; 3 estimate future areas according to forecasted scenarios of climate change; and 4 quantify habitat suitability changes between present and future climatic scenarios. Field observations were combined with environmental factors to derive an ensemble of predictions of species occurrence. The resulting models were projected to the future North African environmental scenarios. Species occurrence was most related to precipitation variation. Present suitable habitats were fragmented and ranged from coastal to mountain habitats, and the overall fragmented range suggests a relict distribution from wider past ranges. Future projections suggest a progressive decrease in suitable areas. The relationship with precipitation supports the current unsuitability of most North Africa for the species and predicts future increased extinction risk. Monitoring of population trends and full protection of mountain forests are key-targets for long-term conservation of African populations of this viper. Predicted trends may give indications about other peripheral populations of Palearctic vertebrates in North Africa which should be assessed in detail.

  16. Modeling and management of pit lake water chemistry 1: Theory

    International Nuclear Information System (INIS)

    Castendyk, D.N.; Eary, L.E.; Balistrieri, L.S.

    2015-01-01

    Highlights: • Review of pit lake literature in the context of pit lake predictions. • Review of approaches used to predict pit wall-rock runoff and leachate. • Review of approaches used to generate a pit lake water balance. • Review of approaches used to generate a hydrodynamic prediction. • Review of approaches used to generate a geochemical prediction of a future pit lake. - Abstract: Pit lakes are permanent hydrologic/landscape features that can result from open pit mining for metals, coal, uranium, diamonds, oil sands, and aggregates. Risks associated with pit lakes include local and regional impacts to water quality and related impacts to aquatic and terrestrial ecosystems. Stakeholders rely on predictive models of water chemistry to prepare for and manage these risks. This paper is the first of a two part series on the modeling and management of pit lakes. Herein, we review approaches that have been used to quantify wall-rock runoff geochemistry, wall-rock leachate geochemistry, pit lake water balance, pit lake limnology (i.e. extent of vertical mixing), and pit lake water quality, and conclude with guidance on the application of models within the mine life cycle. The purpose of this paper is to better prepare stakeholders, including future modelers, mine managers, consultants, permitting agencies, land management agencies, regulators, research scientists, academics, and other interested parties, for the challenges of predicting and managing future pit lakes in un-mined areas

  17. Markov Chain Models for the Stochastic Modeling of Pitting Corrosion

    Directory of Open Access Journals (Sweden)

    A. Valor

    2013-01-01

    Full Text Available The stochastic nature of pitting corrosion of metallic structures has been widely recognized. It is assumed that this kind of deterioration retains no memory of the past, so only the current state of the damage influences its future development. This characteristic allows pitting corrosion to be categorized as a Markov process. In this paper, two different models of pitting corrosion, developed using Markov chains, are presented. Firstly, a continuous-time, nonhomogeneous linear growth (pure birth Markov process is used to model external pitting corrosion in underground pipelines. A closed-form solution of the system of Kolmogorov's forward equations is used to describe the transition probability function in a discrete pit depth space. The transition probability function is identified by correlating the stochastic pit depth mean with the empirical deterministic mean. In the second model, the distribution of maximum pit depths in a pitting experiment is successfully modeled after the combination of two stochastic processes: pit initiation and pit growth. Pit generation is modeled as a nonhomogeneous Poisson process, in which induction time is simulated as the realization of a Weibull process. Pit growth is simulated using a nonhomogeneous Markov process. An analytical solution of Kolmogorov's system of equations is also found for the transition probabilities from the first Markov state. Extreme value statistics is employed to find the distribution of maximum pit depths.

  18. Parturition pit: the bony imprint of vaginal birth

    International Nuclear Information System (INIS)

    McArthur, Tatum A.; Meyer, Isuzu; Jackson, Bradford; Pitt, Michael J.; Larrison, Matthew C.

    2016-01-01

    To retrospectively evaluate for pits along the dorsum of the pubic body in females and compare the presence/absence of these pits to vaginal birth data. We retrospectively reviewed females with vaginal birth data who underwent pelvic CT. The presence of pits along the dorsum of the pubic body, pit grade (0 = not present; 1 = faintly imperceptible; 2 = present; 3 = prominent), and the presence of osteitis condensans ilii, preauricular sulcus, and sacroiliac joint vacuum phenomenon were assessed on imaging. Musculoskeletal radiologists who were blinded to the birth data evaluated the CTs. 48 males were also evaluated for the presence of pits. 482 female patients underwent CT pelvis and 171 were excluded due to lack of vaginal birth data. Of the 311 study patients, 262 had prior vaginal birth(s) and 194 had pits on CT. Only 7 of the 49 patients without prior vaginal birth had pits. There was a statistically significant association between vaginal birth and presence of pits (p < 0.0001). Patients with more prominent pits (grades 2/3) had a greater number of vaginal births. As vaginal deliveries increased, the odds of having parturition pits greatly increased, adjusting for age and race at CT (p < 0.0001). No males had pits. Our study indicates that parturition pits are associated with prior vaginal birth and should be considered a characteristic of the female pelvis. The lytic appearance of prominent pits on imaging can simulate disease and create a diagnostic dilemma for interpreting radiologists. (orig.)

  19. Modelling the filling rate of pit latrines

    African Journals Online (AJOL)

    2012-09-18

    Sep 18, 2012 ... the transfer of water into and out of the pit, biological trans- formations, and pathogen die-off (Buckley et al., 2008). .... formations that consumed or generated it. However, the age distribution of the originally deposited unbiodegradable mate- rial depends only on the deposition history, as it undergoes no.

  20. Evaluation of PIT-tagging in cyprinids

    DEFF Research Database (Denmark)

    Skov, Christian; Brodersen, J.; Brönmark, C.

    2005-01-01

    Laboratory and field experiments were used to investigate how different marking procedures, with 23 mm PIT (passive integrated transponders) - tags. affected mortality, body condition and tag expulsion in small roach Rutilus rutilus and rudd Scardinus erythrophthalmus (117 to 163 mm total length...

  1. The Application of Foundation Pit Monitoring Technology to the Excavation

    Directory of Open Access Journals (Sweden)

    Qiu Jin

    2015-01-01

    Full Text Available The foundation pit monitoring plays an important role in the foundation pit supporting projects especially in those deep foundation pit projects. Through the whole monitoring of the foundation pit construction from the excavation to the backfill, we can learn about the forcing and deforming process of the foundation pit supporting system, and grasp the impact of external condition changes on the foundation pit. This paper takes a project in Jinan as an example to establish a specific monitoring program, and then conducts the analysis and evaluation of the monitoring data; the real-time grasp of the foundation pit deformation and internal force changes can help to further ensure the security status of the foundation pit, thus better guiding the construction.

  2. Some questions on small uranium open-pit mines

    International Nuclear Information System (INIS)

    Li Junyi

    1992-01-01

    The experiences of the existing uranium open pits are summarized and the questions in design, erection and production are analyzed. It is important helpful to develop and to design such economical and reasonable small uranium open pits

  3. Pit Study, Geographic NAD83, LOSCO (1999) [pit_study_LOSCO_1998

    Data.gov (United States)

    Louisiana Geographic Information Center — The 'Pit Study' was meant to identify the remnants of former oil extraction sites which pose the threat of creating an oil spill. These remnants include many other...

  4. The VIMOS Public Extragalactic Redshift Survey (VIPERS). The distinct build-up of dense and normal massive passive galaxies

    Science.gov (United States)

    Gargiulo, A.; Bolzonella, M.; Scodeggio, M.; Krywult, J.; De Lucia, G.; Guzzo, L.; Garilli, B.; Granett, B. R.; de la Torre, S.; Abbas, U.; Adami, C.; Arnouts, S.; Bottini, D.; Cappi, A.; Cucciati, O.; Davidzon, I.; Franzetti, P.; Fritz, A.; Haines, C.; Hawken, A. J.; Iovino, A.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; Marulli, F.; Moutard, T.; Polletta, M.; Pollo, A.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Zamorani, G.; Bel, J.; Branchini, E.; Coupon, J.; Ilbert, O.; Moscardini, L.; Peacock, J. A.

    2017-10-01

    We have used the final data from the VIPERS redshift survey to extract an unparalleled sample of more than 2000 massive ℳ≥1011 M⊙ passive galaxies (MPGs) at redshift 0.5≤z≤1.0, based on their NUVrK colours. This has enabled us to investigate how the population of these objects was built up over cosmic time. We find that the evolution of the number density depends on the galaxy mean surface stellar mass density, Σ. In particular, dense (Σ≥2000 M⊙ pc-2) MPGs show a constant comoving number density over this redshift range, whilst this increases by a factor of approximately four for the least dense objects, defined as having Σ ages for the MPG population both fitting the spectral energy distribution (SED) and through the D4000n index, obtaining results in good agreement. Our findings are consistent with passive ageing of the stellar content of dense MPGs. We show that at any redshift the less dense MPGs are younger than dense ones and that their stellar populations evolve at a slower rate than predicted by passive evolution. This points to a scenario in which the overall population of MPGs was built up over the cosmic time by continuous addition of less dense galaxies: on top of an initial population of dense objects that passively evolves, new, larger, and younger MPGs continuously join the population at later epochs. Finally, we demonstrate that the observed increase in the number density of MPGs is totally accounted for by the observed decrease in the number density of correspondingly massive star forming galaxies (I.e. all the non-passive ℳ≥1011 M⊙ objects). Such systems observed at z ≃ 1 in VIPERS, therefore, represent the most plausible progenitors of the subsequent emerging class of larger MPGs. Based on observations collected at the European Southern Observatory, Cerro Paranal, Chile, using the Very Large Telescope under programs 182.A-0886 and partly 070.A-9007. Also based on observations obtained with MegaPrime/MegaCam, a joint

  5. Open Pit Water Control Safety A Case Of Nchanga Open Pit Mine Zambia

    Directory of Open Access Journals (Sweden)

    Silwamba C

    2015-08-01

    Full Text Available Abstract Mining in Chingola Zambia started underground in 1931 and was catastrophically flooded and closed. The present Nchanga Underground Mine NUG started in 1937. The Nchanga Open Pit NOP mine started in 1955 situated to the west of NUG and partially overlying it. Open pit water control safety operations in the Nchanga-Chingola area have successfully enabled the safe extraction of millions of tonnes of copper ore annually over the past 60 years from NUG mining as well as the NOP. At the start Nchanga mining license surface already had NUG and many watershed divides with the Nchanga and Chingola streams being the main streams feeding into Zambias second largest river Kafue river and 42 of the year was characterised by heavy rains ranging between 800mm to 1300mm per annum. In this paper the presence of very significant amounts of seasonal rain and subsurface water in the mining area was identified as both a curse and a blessing. An excess in seasonal rain and subsurface water would disrupt both open pit and underground mining operations. In order for NOP to be operated successfully stable and free from flooding coping water management tactics were adopted from 1955 to 2015 including 1. Underground mine pump chamber pumping system 2. Piezometer instrumented boreholes 3. Underground mine 1500-ft sub-haulage east borehole dewatering beneath the open pit 4. Nchanga and Chingola stream diversionary tunnel and open drains 5. Nchanga stream causeway and embankment dam in the Matero School Golf Club area 6. Pit perimeter borehole pumping 7. Outer and inner pit perimeter drains and bund walls 8. In-pit ramp side drains 9. In-pit sub-horizontal borehole geo-drains and water and 10. Pit bottom sump pumps. Application of grout curtains along the Vistula River Poland was noted as a possibility in the right circumstances although it had never been used at Nchanga Open Pit. An additional conclusion was that forward health safety and environmental end

  6. Application of Surpac and Whittle Software in Open Pit Optimisation ...

    African Journals Online (AJOL)

    Pit 36 was chosen having the highest the Net Present Value (NPV) @ 10% of $338.60 million. The optimal pit had 21.19 Mt of ore at an average grade of 1.557 g/t. The NPV was very sensitive to gold price changes but marginally sensitive to mining cost changes. From the optimal pit, a detailed pit designed with circular ...

  7. Interacting Effects Induced by Two Neighboring Pits Considering Relative Position Parameters and Pit Depth

    Directory of Open Access Journals (Sweden)

    Yongfang Huang

    2017-04-01

    Full Text Available For pre-corroded aluminum alloy 7075-T6, the interacting effects of two neighboring pits on the stress concentration are comprehensively analyzed by considering various relative position parameters (inclination angle θ and dimensionless spacing parameter λ and pit depth (d with the finite element method. According to the severity of the stress concentration, the critical corrosion regions, bearing high susceptibility to fatigue damage, are determined for intersecting and adjacent pits, respectively. A straightforward approach is accordingly proposed to conservatively estimate the combined stress concentration factor induced by two neighboring pits, and a concrete application example is presented. It is found that for intersecting pits, the normalized stress concentration factor Ktnor increases with the increase of θ and λ and always reaches its maximum at θ = 90°, yet for adjacent pits, Ktnor decreases with the increase of λ and the maximum value appears at a slight asymmetric location. The simulations reveal that Ktnor follows a linear and an exponential relationship with the dimensionless depth parameter Rd for intersecting and adjacent cases, respectively.

  8. Upward Altitudinal Shifts in Habitat Suitability of Mountain Vipers since the Last Glacial Maximum.

    Science.gov (United States)

    Yousefi, Masoud; Ahmadi, Mohsen; Nourani, Elham; Behrooz, Roozbeh; Rajabizadeh, Mehdi; Geniez, Philippe; Kaboli, Mohammad

    2015-01-01

    We determined the effects of past and future climate changes on the distribution of the Montivipera raddei species complex (MRC) that contains rare and endangered viper species limited to Iran, Turkey and Armenia. We also investigated the current distribution of MRC to locate unidentified isolated populations as well as to evaluate the effectiveness of the current network of protected areas for their conservation. Present distribution of MRC was modeled based on ecological variables and model performance was evaluated by field visits. Some individuals at the newly identified populations showed uncommon morphological characteristics. The distribution map of MRC derived through modeling was then compared with the distribution of protected areas in the region. We estimated the effectiveness of the current protected area network to be 10%, which would be sufficient for conserving this group of species, provided adequate management policies and practices are employed. We further modeled the distribution of MRC in the past (21,000 years ago) and under two scenarios in the future (to 2070). These models indicated that climatic changes probably have been responsible for an upward shift in suitable habitats of MRC since the Last Glacial Maximum, leading to isolation of allopatric populations. Distribution will probably become much more restricted in the future as a result of the current rate of global warming. We conclude that climate change most likely played a major role in determining the distribution pattern of MRC, restricting allopatric populations to mountaintops due to habitat alterations. This long-term isolation has facilitated unique local adaptations among MRC populations, which requires further investigation. The suitable habitat patches identified through modeling constitute optimized solutions for inclusion in the network of protected areas in the region.

  9. Viper venom hyaluronidase and its potential inhibitor analysis: a multipronged computational investigation.

    Science.gov (United States)

    Sivaramakrishnan, V; Ilamathi, M; Girish, K S; Kemparaju, K; Rangappa, K S; Dhananjaya, Bhadrapura Lakkappa

    2017-07-01

    Viper venom hyaluronidase (VV-HYA) inhibitors have long been used as therapeutic agents for arresting the local and systemic effects caused during its envenomation. Henceforth, to understand its structural features and also to identify the best potential inhibitor against it the present computational study was undertaken. Structure-based homology modeling of VV-HYA followed by its docking and free energy-based ranking analysis of ligand, the MD simulations of the lead complex was also performed. The sequence analysis and homology modeling of VV-HYA revealed a distorted (β/α) 8 folding as in the case of hydrolases family of proteins. Molecular docking of the resultant 3D structure of VV-HYA with known inhibitors (compounds 1-25) revealed the importance of molecular recognition of hotspot residues (Tyr 75, Arg 288, and Trp 321) other than that of the active site residues. It also revealed that Trp 321 of VV-HYA is highly important for mediating π-π interactions with ligands. In addition, the molecular docking and comparative free energy binding analysis was investigated for the VV-HYA inhibitors (compounds 1-25). Both molecular docking and relative free energy binding analysis clearly confirmed the identification of sodium chromoglycate (compound 1) as the best potential inhibitor against VV-HYA. Molecular dynamics simulations additionally confirmed the stability of their binding interactions. Further, the information obtained from this work is believed to serve as an impetus for future rational designing of new novel VV-HYA inhibitors with improved activity and selectivity.

  10. Upward Altitudinal Shifts in Habitat Suitability of Mountain Vipers since the Last Glacial Maximum.

    Directory of Open Access Journals (Sweden)

    Masoud Yousefi

    Full Text Available We determined the effects of past and future climate changes on the distribution of the Montivipera raddei species complex (MRC that contains rare and endangered viper species limited to Iran, Turkey and Armenia. We also investigated the current distribution of MRC to locate unidentified isolated populations as well as to evaluate the effectiveness of the current network of protected areas for their conservation. Present distribution of MRC was modeled based on ecological variables and model performance was evaluated by field visits. Some individuals at the newly identified populations showed uncommon morphological characteristics. The distribution map of MRC derived through modeling was then compared with the distribution of protected areas in the region. We estimated the effectiveness of the current protected area network to be 10%, which would be sufficient for conserving this group of species, provided adequate management policies and practices are employed. We further modeled the distribution of MRC in the past (21,000 years ago and under two scenarios in the future (to 2070. These models indicated that climatic changes probably have been responsible for an upward shift in suitable habitats of MRC since the Last Glacial Maximum, leading to isolation of allopatric populations. Distribution will probably become much more restricted in the future as a result of the current rate of global warming. We conclude that climate change most likely played a major role in determining the distribution pattern of MRC, restricting allopatric populations to mountaintops due to habitat alterations. This long-term isolation has facilitated unique local adaptations among MRC populations, which requires further investigation. The suitable habitat patches identified through modeling constitute optimized solutions for inclusion in the network of protected areas in the region.

  11. Laboratory protocols for testing the efficacy of commercial pit latrine ...

    African Journals Online (AJOL)

    There is considerable national interest in the use of commercial microbially derived products for controlling the rate of accumulation of the contents of pit latrines. Manufacturers claim that some of these products can reduce accumulation rates, prevent the pit from ever filling up, or even result in decreases in pit contents ...

  12. Application of Surpac and Whittle Software in Open Pit Optimisation ...

    African Journals Online (AJOL)

    Michael

    2015-06-01

    Jun 1, 2015 ... This paper studies the Surpac and Whittle software and their application in designing an optimised pit. Exploration data from. Mpeasem Gold Mining Project (MGMP) is used as the primary input for the work. The work entails: block modelling of. MGMP deposit; pit optimisation; analysis of the Pit NPV's ...

  13. Congenital pits of the optic nerve head and retinochoroidal colobomas.

    Science.gov (United States)

    Brown, G C; Augsburger, J J

    1980-07-01

    A 45-year-old man presented with bilateral retinochoroidal colobomas associated with an inferonasal congenital pit of the optic nerve head in each eye. Different theories on the origin of such pits are discussed. This case supports the theory that some congenital optic pits occur as a result of failure of closure of the superior end of the embryonic fissure.

  14. Analysis of BY-106 pump pit cover plate

    International Nuclear Information System (INIS)

    Coverdell, B.L.

    1994-01-01

    A new cover for the pump pit of Tank 241-BY-106 has been designed to allow the rotary core exhauster to be hooked up without requiring pit entry, riser modification, or equipment removal. The new pit cover is necessary to allow installation of two risers for reducing exposure, contamination, and waste. Computer analysis indicates that the safety margin of the pit cover plate with two risers is adequate. The computer stress model and input files are attached. The pit cover plate is a replacement for an existing plate; therefore seismic and wind loads were considered for the plate only

  15. One strategy for arthroscopic suture fixation of tibial intercondylar eminence fractures using the Meniscal Viper Repair System

    Directory of Open Access Journals (Sweden)

    Ochiai Satoshi

    2011-08-01

    Full Text Available Abstract Background Principles for the treatment of tibial intercondylar eminence fracture are early reduction and stable fixation. Numerous ways to treatment of this fracture have been invented. We designed a simple, low-invasive, and arthroscopic surgical strategy for tibial intercondylar eminence fracture utilizing the Meniscal Viper Repair System used for arthroscopic meniscal suture. Methods We studied 5 patients, who underwent arthroscopic suture fixation that we modified. The present technique utilized the Meniscal Viper Repair System for arthroscopic suture of the meniscus. With one handling, a high-strength ultra-high molecular weight polyethylene(UHMWPE suture can be passed through the anterior cruciate ligament (ACL and the loops for suture retrieval placed at both sides of ACL. Surgical results were evaluated by the presence or absence of bone union on plain radiographs, postoperative range of motion of the knee joint, the side-to-side differences measured by Telos SE, and Lysholm scores. Results The reduced position achieved after surgery was maintained and good function was obtained in all cases. The mean distance of tibia anterior displacement and assessment by Lysholm score showed good surgical results. Conclusion This method simplified the conventional arthroscopic suture fixation and increased its precision, and was applicable to Type II fractures that could be reduced, as well as surgically indicated Types III and IV. The present series suggested that our surgical approach was a useful surgical intervention for tibial intercondylar eminence fracture.

  16. Quantitative Proteomic Analysis of Venoms from Russian Vipers of Pelias Group: Phospholipases A₂ are the Main Venom Components.

    Science.gov (United States)

    Kovalchuk, Sergey I; Ziganshin, Rustam H; Starkov, Vladislav G; Tsetlin, Victor I; Utkin, Yuri N

    2016-04-12

    Venoms of most Russian viper species are poorly characterized. Here, by quantitative chromato-mass-spectrometry, we analyzed protein and peptide compositions of venoms from four Vipera species (V. kaznakovi, V. renardi, V. orlovi and V. nikolskii) inhabiting different regions of Russia. In all these species, the main components were phospholipases A₂, their content ranging from 24% in V. orlovi to 65% in V. nikolskii. Altogether, enzyme content in venom of V. nikolskii reached ~85%. Among the non-enzymatic proteins, the most abundant were disintegrins (14%) in the V. renardi venom, C-type lectin like (12.5%) in V. kaznakovi, cysteine-rich venom proteins (12%) in V. orlovi and venom endothelial growth factors (8%) in V. nikolskii. In total, 210 proteins and 512 endogenous peptides were identified in the four viper venoms. They represented 14 snake venom protein families, most of which were found in the venoms of Vipera snakes previously. However, phospholipase B and nucleotide degrading enzymes were reported here for the first time. Compositions of V. kaznakovi and V. orlovi venoms were described for the first time and showed the greatest similarity among the four venoms studied, which probably reflected close relationship between these species within the "kaznakovi" complex.

  17. 5G in Open-Pit Mines

    DEFF Research Database (Denmark)

    Portela Lopes de Almeida, Erika; Caldwell, George; Rodriguez Larrad, Ignacio

    2017-01-01

    for the future wireless network design, simulation and performance evaluation. The results show that, in order to comply with ultra-reliable communications (URC) availability requirements, larger shadowing margins will have to be considered in the network planning in open-pit mines, when compared to traditional......5G will play a pivotal role in the digitization of the industrial sector and is expected to make the best use of every bit of spectrum available. In this light, this paper presents the results of an extensive measurement campaign in two iron-ore open-pit mining complexes, at the 700 MHz and 2.6 GHz...... bands, considering macro and small cell deployments. The study is further motivated by the rise of unmanned machinery in the mining industry. We present values of path loss exponents, shadow fading standard deviations, autocorrelation distances and inter-frequency cross-correlation, which are all useful...

  18. Treatment of a mud pit by bioremediation.

    Science.gov (United States)

    Avdalović, Jelena; Đurić, Aleksandra; Miletić, Srdjan; Ilić, Mila; Milić, Jelena; Vrvić, Miroslav M

    2016-08-01

    The mud generated from oil and natural gas drilling, presents a considerable ecological problem. There are still insufficient remedies for the removal and minimization of these very stable emulsions. Existing technologies that are in use, more or less successfully, treat about 20% of generated waste drilling mud, while the rest is temporarily deposited in so-called mud pits. This study investigated in situ bioremediation of a mud pit. The bioremediation technology used in this case was based on the use of naturally occurring microorganisms, isolated from the contaminated site, which were capable of using the contaminating substances as nutrients. The bioremediation was stimulated through repeated inoculation with a zymogenous microbial consortium, along with mixing, watering and biostimulation. Application of these bioremediation techniques reduced the concentration of total petroleum hydrocarbons from 32.2 to 1.5 g kg(-1) (95% degradation) during six months of treatment. © The Author(s) 2016.

  19. 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.

  20. Investigating pitting in X65 carbon steel using potentiostatic polarisation

    Science.gov (United States)

    Mohammed, Sikiru; Hua, Yong; Barker, R.; Neville, A.

    2017-11-01

    Although pitting corrosion in passive materials is generally well understood, the growth of surface pits in actively-corroding materials has received much less attention to date and remains poorly understood. One of the key challenges which exists is repeatedly and reliably generating surface pits in a practical time-frame in the absence of deformation and/or residual stress so that studies on pit propagation and healing can be performed. Another pertinent issue is how to evaluate pitting while addressing general corrosion in low carbon steel. In this work, potentiostatic polarisation was employed to induce corrosion pits (free from deformation or residual stress) on actively corroding X65 carbon steel. The influence of applied potential (50 mV, 100 mV and 150 mV vs open circuit potential) was investigated over 24 h in a CO2-saturated, 3.5 wt.% NaCl solution at 30 °C and pH 3.8. Scanning electron microscopy (SEM) was utilised to examine pits, while surface profilometry was conducted to measure pit depth as a function of applied potential over the range considered. Analyses of light pitting (up to 120 μm) revealed that pit depth increased linearly with increase in applied potential. This paper relates total pit volume (measured using white light interferometry) to dissipated charge or total mass loss (using the current response for potentiostatic polarisation in conjunction with Faraday's law). By controlling the potential of the surface (anodic) the extent of pitting and general corrosion could be controlled. This allowed pits to be evaluated for their ability to continue to propagate after the potentiostatic technique was employed. Linear growth from a depth of 70 μm at pH 3.8, 80 °C was demonstrated. The technique offers promise for the study of inhibition of pitting.

  1. Influence of Pitting Corrosion on Fatigue and Corrosion Fatigue of Ship and Offshore Structures, Part II: Load - Pit - Crack Interaction

    Directory of Open Access Journals (Sweden)

    Jakubowski Marek

    2015-09-01

    Full Text Available In the paper has been discussed influence of stresses on general corrosion rate and corrosion pit nucleation rate and growth , whose presence has been questioned by some authors but accepted by most of them. Influence of roughness of pit walls on fatigue life of a plate suffering pit corrosion and presence of the so called „ non-damaging” pits which never lead to initiation of fatigue crack, has been presented. Possibility of prediction of pit-to-crack transition moment by two different ways, i.e. considering a pit a stress concentrator or an equivalent crack, has been analyzed. Also, influence of statistical distribution of depth of corrosion pits as well as anticorrosion protection on fatigue and corrosion fatigue has been described.

  2. Clinico epidemiological study of pitted keratolysis

    Directory of Open Access Journals (Sweden)

    Naik Chandra

    2007-01-01

    Full Text Available Background: Pitted keratolysis is a common dermatological condition. However, very few studies are available on the clinical characteristics and epidemiological features of this disorder from India and abroad. Materials and Methods: Fifty patients from rural area of Kolar at Sri R.L.J.H. and S.N.R. Hospital, presenting with clinically distinctive lesions of pitted keratolysis were included in the study. Cases were interviewed with particular emphasis on triggering factors and findings were recorded. Investigations like Gram′s stain, culture studies, Wood′s ultraviolet light examination, histopathology etc, was done in selected cases to ascertain the clinical diagnosis. Results: Age of the patients varied from 20 to 40 years in 52% with male preponderance in 82% of cases. Duration of the disease varied from 15 days to five years, most of the patients were bare-footed farmers (62% of cases. Hyperhidrosis and pruritus were most frequently observed symptoms in 70% and 60% of patients. Most of the patients presented with the characteristic pits which varied from 1 to 50 in number in 56 % of cases, located predominantly on the pressure bearing areas in 92% of cases and depth of the pits varied from 1 to 2 mm in 60% of cases. Associated skin conditions recorded in present study were fissuring of soles in 38%, psoriasis 10%, dermatophyte infections in 6%, planter warts 6% and Corynebacterial triad and corn in 2% of patients each. Discussion: Affection of bare-footed individuals, male preponderance, presence of hyperhidrosis and occurrence of lesions over pressure bearing areas of soles, observed in the present study were consistent with earlier studies on the subject. However, pruritus as commonest presenting symptom reported by 60% patients in the present study, has not been documented in the previous studies. Conclusion: Pitted keratolysis is fairly common in bare footed male farmers of rural India. The condition is predominantly seen over the

  3. Neurotoxicity in Sri Lankan Russell's Viper (Daboia russelii) Envenoming is Primarily due to U1-viperitoxin-Dr1a, a Pre-Synaptic Neurotoxin.

    Science.gov (United States)

    Silva, Anjana; Kuruppu, Sanjaya; Othman, Iekhsan; Goode, Robert J A; Hodgson, Wayne C; Isbister, Geoffrey K

    2017-01-01

    Russell's vipers are snakes of major medical importance in Asia. Russell's viper (Daboia russelii) envenoming in Sri Lanka and South India leads to a unique, mild neuromuscular paralysis, not seen in other parts of the world where the snake is found. This study aimed to identify and pharmacologically characterise the major neurotoxic components of Sri Lankan Russell's viper venom. Venom was fractionated using size exclusion chromatography and reverse-phase high-performance liquid chromatography (RP-HPLC). In vitro neurotoxicities of the venoms, fractions and isolated toxins were measured using chick biventer and rat hemidiaphragm preparations. A phospholipase A 2 (PLA 2 ) toxin, U1-viperitoxin-Dr1a (13.6 kDa), which constitutes 19.2 % of the crude venom, was isolated and purified using HPLC. U1-viperitoxin-Dr1a produced concentration-dependent in vitro neurotoxicity abolishing indirect twitches in the chick biventer nerve-muscle preparation, with a t 90 of 55 ± 7 min only at 1 μM. The toxin did not abolish responses to acetylcholine and carbachol indicating pre-synaptic neurotoxicity. Venom, in the absence of U1-viperitoxin-Dr1a, did not induce in vitro neurotoxicity. Indian polyvalent antivenom, at the recommended concentration, only partially prevented the neurotoxic effects of U1-viperitoxin-Dr1a. Liquid chromatography mass spectrometry analysis confirmed that U1-viperitoxin-Dr1a was the basic S-type PLA 2 toxin previously identified from this venom (NCBI-GI: 298351762; SwissProt: P86368). The present study demonstrates that neurotoxicity following Sri Lankan Russell's viper envenoming is primarily due to the pre-synaptic neurotoxin U1-viperitoxin-Dr1a. Mild neurotoxicity observed in severely envenomed Sri Lankan Russell's viper bites is most likely due to the low potency of U1-viperitoxin-Dr1a, despite its high relative abundance in the venom.

  4. Detecting pits in tart cherries by hyperspectral transmission imaging

    Science.gov (United States)

    Qin, Jianwei; Lu, Renfu

    2004-11-01

    The presence of pits in processed cherry products causes safety concerns for consumers and imposes potential liability for the food industry. The objective of this research was to investigate a hyperspectral transmission imaging technique for detecting the pit in tart cherries. A hyperspectral imaging system was used to acquire transmission images from individual cherry fruit for four orientations before and after pits were removed over the spectral region between 450 nm and 1,000 nm. Cherries of three size groups (small, intermediate, and large), each with two color classes (light red and dark red) were used for determining the effect of fruit orientation, size, and color on the pit detection accuracy. Additional cherries were studied for the effect of defect (i.e., bruises) on the pit detection. Computer algorithms were developed using the neural network (NN) method to classify the cherries with and without the pit. Two types of data inputs, i.e., single spectra and selected regions of interest (ROIs), were compared. The spectral region between 690 nm and 850 nm was most appropriate for cherry pit detection. The NN with inputs of ROIs achieved higher pit detection rates ranging from 90.6% to 100%, with the average correct rate of 98.4%. Fruit orientation and color had a small effect (less than 1%) on pit detection. Fruit size and defect affected pit detection and their effect could be minimized by training the NN with properly selected cherry samples.

  5. Bingham Pump Outage Pits: Environmental information document

    International Nuclear Information System (INIS)

    Pekkala, R.O.; Jewell, C.E.; Holmes, W.G.; Marine, I.W.

    1987-03-01

    Seven waste sites known as the Bingham Pump Outage Pits located in areas of the Savannah River Plant (SRP) received solid waste containing an estimated 4 Ci of low-level radioactivity in 1957-1958. These sites were subsequently backfilled and have been inactive since that time. Most of the radioactivity at the Bingham Pump Outage Pits has been eliminated by radioactive decay. A total of approximately 1 Ci of activity (primarily 137 Cs and 90 Sr) is estimated to remain at the seven sites. The closure options considered for the Bingham Pump Outage Pits are waste removal and closure, no waste removal and closure, and no action. The predominant pathways for human exposure to chemical and/or radioactive constituents are through surface, subsurface, and atmospheric transport. Modeling calculations were made to determine the risks to human population via these general pathways for the three postulated closure options. An ecological assessment was conducted to predict the environmental impacts on aquatic and terrestrial biota. The relative costs for each of the closure options were estimated. Evaluation indicates that the relative human health risks for all closure options are small. The greatest public risk would occur after the waste site was released to unrestricted public use (assumed to occur in Year 2085) via the groundwater pathway to a well. The cost estimates show that the waste removal and closure option is the most expensive (89.6 million dollars). The cost of the no waste removal and the no action options is $800,000. 35 refs., 26 figs., 47 tabs

  6. The stochastic model of pitting corrosion of metals

    Science.gov (United States)

    You, Y. H.; Wang, B. R.; Hu, H. Y.

    2017-12-01

    Considering that pitting corrosion is a stochastic process, the purpose of this paper is to use stochastic theory to investigate the growth process of pitting corrosion of metals. Based on the mechanism of pit growth and nonequilibrium statistical theory, the time evolution equations of pit depth and corrosion rate are obtained, and the probability density function can be derived by solving Fock-Plank Equation. Subsequently, the failure probability or reliability of metals is calculated based on the weakest link model of pitting corrosion. Finally, the stochastic model is used on the aircraft aluminum alloy LD2. Furthermore, this methodology can be applied to analyze the reliability and predict the pitting life of metals.

  7. Markov chain modelling of pitting corrosion in underground pipelines

    International Nuclear Information System (INIS)

    Caleyo, F.; Velazquez, J.C.; Valor, A.; Hallen, J.M.

    2009-01-01

    A continuous-time, non-homogenous linear growth (pure birth) Markov process has been used to model external pitting corrosion in underground pipelines. The closed form solution of Kolmogorov's forward equations for this type of Markov process is used to describe the transition probability function in a discrete pit depth space. The identification of the transition probability function can be achieved by correlating the stochastic pit depth mean with the deterministic mean obtained experimentally. Monte-Carlo simulations previously reported have been used to predict the time evolution of the mean value of the pit depth distribution for different soil textural classes. The simulated distributions have been used to create an empirical Markov chain-based stochastic model for predicting the evolution of pitting corrosion depth and rate distributions from the observed properties of the soil. The proposed model has also been applied to pitting corrosion data from pipeline repeated in-line inspections and laboratory immersion experiments.

  8. Thallium toxicosis in a Pit Bull Terrier.

    Science.gov (United States)

    Volmer, Petra A; Merola, Valentina; Osborne, Tanasa; Bailey, Keith L; Meerdink, Gavin

    2006-01-01

    Thallotoxicosis is described in an adult Pit Bull Terrier. The dog exhibited anorexia, emesis, weakness, conscious proprioceptive deficits, and a hemorrhagic diarrhea before death. A severe, acute necrotizing enterocolitis was evident upon histological examination, as was a multifocal to coalescing pulmonary edema. Liver and kidney thallium concentrations were 18 and 26 ppm, respectively. The source of the thallium was determined to be thallium sulfate obtained by a person with the intent to harm family members. Although thallium has not been produced in the United States for 20 years, this report demonstrates the need to consider thallium toxicosis as a differential diagnosis for animals presenting with vague and mixed gastrointestinal and neurological signs.

  9. The Pit and the Safety Pendulum

    Energy Technology Data Exchange (ETDEWEB)

    Nitschke, Robert Leon; Ramos, Amadeo Gabriel

    2000-11-01

    The hypothesis of this paper is that the safety analysis pendulum has swung considerably in the direction of increasingly complex and lengthy safety evaluations and intense reviews during the past 30 years. The test of this hypothesis will be a review of the safety analysis conducted for various activities associated with the retrieval of transuranic radioactive waste from burial pits at a National Laboratory site over a span of 30 years. The examination will focus on the safety aspects and the safety analysis that was conducted for the projects. At the conclusion of this examination, the paper will identify five reasons why the changes have taken place.

  10. Comparative toxicity of diphacinone to northern bobwhite (Colinus virginianus) and American kestrels (Falco sparverius)

    Science.gov (United States)

    Rattner, Barnett A.; Horak, Katherine E.; Warner, Sarah E.; Day, Daniel D.; Johnston, John J.

    2010-01-01

    The acute oral toxicity of the anticoagulant rodenticide diphacinone was found to be about 20 times greater to American kestrels (LD50=97 mg/kg) than to northern bobwhite (LD50=2,014 mg/kg). Several precise and sensitive clotting assays (prothrombin time, Russell's Viper venom time, thrombin clotting time) were adapted for use in these species, and this combination of assays is recommended to detect effects of diphacinone and other rodenticides on coagulation. Oral administration of diphacinone over a range of doses (sublethal to the extrapolated LD15) prolonged prothrombin time and Russell's Viper venom time within 24 to 48 hrs post-exposure. Prolongation of in vitro clotting time reflects impaired coagulation complex activity and was detected before or at the onset of overt signs of toxicity and lethality. These data will assist in the development of a pharmacodynamic model to assess and predict rodenticide toxicity to non-target avian species.

  11. Markov Chain Models for the Stochastic Modeling of Pitting Corrosion

    OpenAIRE

    Valor, A.; Caleyo, F.; Alfonso, L.; Velázquez, J. C.; Hallen, J. M.

    2013-01-01

    The stochastic nature of pitting corrosion of metallic structures has been widely recognized. It is assumed that this kind of deterioration retains no memory of the past, so only the current state of the damage influences its future development. This characteristic allows pitting corrosion to be categorized as a Markov process. In this paper, two different models of pitting corrosion, developed using Markov chains, are presented. Firstly, a continuous-time, nonhomogeneous linear growth (pure ...

  12. Fabrication of Nano-pit Array Using Electron Beam Lithography

    International Nuclear Information System (INIS)

    Maryam Alsadat Rad; Kamarulazizi Ibrahim

    2011-01-01

    This work reports the fabrication of nano-pits array pattern using electron beam lithography (EBL). We investigated the effect of different electron beam dosage and acceleration voltage in fabrication nano-pits array pattern and effect of them on dimension of nano-pits. The SEM images have shown effect of the voltage and dosage variation on them and also the proximity effect. (author)

  13. Data on the reproduction of a Caucasian Viper, Vipera kaznakovi Nikolsky, 1909 (Serpentes: Viperidae from Hopa (Northeastern Anatolia, Turkey

    Directory of Open Access Journals (Sweden)

    Bayram Göçmen

    2013-12-01

    Full Text Available In the current study we report an observation of a Caucasian Viper, Vipera kaznakovi from Hopa (Artvin, Turkey giving birth. During our field studies, we captured a female Vipera kaznakovi on July 21, 2012 from Esenkıyı village, Hopa (Artvin, Turkey, it was brought to the laboratory and kept in a terrarium for a period until May 28, 2013. The female (SVL= 483 mm, total length, TL = 541 mm gave birth to eight young (mean SVL= 146 mm, mean TL= 161.4 mm, range= 155 – 172 mm; mean weight, W= 3.11 g, range= 2.6 – 3.4 g on August 11, 2012. In six and a half months, the juvenile snakes had reached 163 mm SVL, 187 mm TL and 5.1g W and increased their size by approximately 15%.

  14. Differentiating percussion pits and carnivore tooth pits using 3D reconstructions and geometric morphometrics.

    Science.gov (United States)

    Yravedra, José; Aramendi, Julia; Maté-González, Miguel Ángel; Austin Courtenay, Lloyd; González-Aguilera, Diego

    2018-01-01

    During the end of the 20th century and the beginning of the 21st century the discussion on early human behavioral patterns revolved around the hunting versus scavenging debate. The correct identification of bone modifications, including percussion, cut and tooth marks, is a key issue within this debate. While many authors have shown that carnivore and human modifications can be easily distinguished, it is true that sometimes percussion marks without associated microstriations and tooth pits overlap morphologically, causing confusion, especially when unmodified hammerstones are used. In order to solve this equifinality problem, many investigations have focused their efforts on other pieces of evidence such as the identification of notches, fragmentation patterns and frequencies, among others. These studies, however, cannot be considered as fully conclusive. Within this paper we address the problem of equifinality when identifying percussion marks produced with unmodified hammerstones and tooth pits created by carnivores using new methodologies based on the 3D reconstruction of marks and their statistical multivariate analysis. For the purpose of this study a total of 128 marks- 39 percussion marks produced with an unmodified quartzite hammerstone, and 89 pits generated by different carnivores-were virtually modelled with the aid of a DAVID structured-light scanner SLS-2 and later analyzed by means of geometric morphometrics. Our results show that percussion marks not associated with striae fields and the pits generated by the carnivores studied here can be successfully distinguished.

  15. Pitting corrosion of Inconel 600 in chloride and thiosulfate solution

    International Nuclear Information System (INIS)

    Yu, Geping; Ho, Juiting.

    1990-01-01

    Inconel 600 has been widely used as the steam generator tube material in nuclear pressurized water reactors. Pitting corrosion of the steam generator tube mainly occurs at the secondary water side. It was reported in several papers that pits formed in Inconel 600 in steam generators always contained sulfur, and the main source of that sulfur was thought to be the feedwater. The thiosulfate anion is known to reduce the pitting potential and increase the corrosion rate of AISI Type 304 stainless steel in chloride at low temperatures. It is recognized as a dangerous corrosion promoter and as a reducer of the pitting potential of Inconel 600 in chloride solutions at high temperatures. In other cases, the addition of low-level sulfate to dilute chloride media reduces the pitting potential of alloy 800 at 30 degree C, and increasing the sulfate concentration results in improved chloride pitting resistance. The purpose of the work reported in this paper is mainly to identify the effect of thiosulfate on the chloride pitting of Inconel 600 at low temperatures and the effects of deoxygenation, pH value, and temperature. This study is divided into three parts: (1) potentiodynamic anodic polarization scanning; (2) open-circuit immersion test; and (3) determination of pit density and average pit depth

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

    Directory of Open Access Journals (Sweden)

    Bo ZHANG

    2017-12-01

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

  17. Population Pharmacokinetics of an Indian F(ab'2 Snake Antivenom in Patients with Russell's Viper (Daboia russelii Bites.

    Directory of Open Access Journals (Sweden)

    Geoffrey K Isbister

    Full Text Available There is limited information on antivenom pharmacokinetics. This study aimed to investigate the pharmacokinetics of an Indian snake antivenom in humans with Russell's viper bites.Patient data and serial blood samples were collected from patients with Russell's viper (Daboia russelii envenoming in Sri Lanka. All patients received Indian F(ab'2 snake antivenom manufactured by VINS Bioproducts Ltd. Antivenom concentrations were measured with sandwich enzyme immunoassays. Timed antivenom concentrations were analysed using MONOLIXvs4.2. One, two and three compartment models with zero order input and first order elimination kinetics were assessed. Models were parameterized with clearance (CL, intercompartmental clearance (Q, central compartment volume (V and peripheral compartment volume (VP. Between-subject-variability (BSV on relative bioavailability (F was included to account for dose variations. Covariates effects (age, sex, weight, antivenom batch, pre-antivenom concentrations were explored by visual inspection and in model building. There were 75 patients, median age 57 years (40-70 y and 64 (85% were male. 411 antivenom concentration data points were analysed. A two compartment model with zero order input, linear elimination kinetics and a combined error model best described the data. Inclusion of BSV on F and weight as a covariate on V improved the model. Inclusion of pre-antivenom concentrations or different batches on BSV of F did not. Final model parameter estimates were CL,0.078 L h(-1, V,2.2L, Q,0.178 L h(-1 and VP,8.33L. The median half-life of distribution was 4.6 h (10-90%iles:2.6-7.1 h and half-life of elimination, 140 h (10th-90th percentilesx:95-223h.Indian F(ab'2 snake antivenom displayed biexponential disposition pharmacokinetics, with a rapid distribution half-life and more prolonged elimination half-life.

  18. Introduction to Pits and Weapons Systems (U)

    Energy Technology Data Exchange (ETDEWEB)

    Kautz, D. [Los Alamos National Laboratory

    2012-07-02

    A Nuclear Explosive Package includes the Primary, Secondary, Radiation Case and related components. This is the part of the weapon that produces nuclear yield and it converts mechanical energy into nuclear energy. The pit is composed of materials that allow mechanical energy to be converted to electromagnetic energy. Fabrication processes used are typical of any metal fabrication facility: casting, forming, machining and welding. Some of the materials used in pits include: Plutonium, Uranium, Stainless Steel, Beryllium, Titanium, and Aluminum. Gloveboxes are used for three reasons: (1) Protect workers and public from easily transported, finely divided plutonium oxides - (a) Plutonium is very reactive and produces very fine particulate oxides, (b) While not the 'Most dangerous material in the world' of Manhattan Project lore, plutonium is hazardous to health of workers if not properly controlled; (2) Protect plutonium from reactive materials - (a) Plutonium is extremely reactive at ambient conditions with several components found in air: oxygen, water, hydrogen, (b) As with most reactive metals, reactions with these materials may be violent and difficult to control, (c) As with most fabricated metal products, corrosion may significantly affect the mechanical, chemical, and physical properties of the product; and (3) Provide shielding from radioactive decay products: {alpha}, {gamma}, and {eta} are commonly associated with plutonium decay, as well as highly radioactive materials such as {sup 241}Am and {sup 238}Pu.

  19. Daptomycin Tolerance in the Staphylococcus aureus pitA6 Mutant Is Due to Upregulation of the dlt Operon.

    Science.gov (United States)

    Mechler, Lukas; Bonetti, Eve-Julie; Reichert, Sebastian; Flötenmeyer, Matthias; Schrenzel, Jacques; Bertram, Ralph; François, Patrice; Götz, Friedrich

    2016-05-01

    Understanding the mechanisms of how bacteria become tolerant toward antibiotics during clinical therapy is a very important object. In a previous study, we showed that increased daptomycin (DAP) tolerance of Staphylococcus aureus was due to a point mutation in pitA (inorganic phosphate transporter) that led to intracellular accumulation of both inorganic phosphate (Pi) and polyphosphate (polyP). DAP tolerance in the pitA6 mutant differs from classical resistance mechanisms since there is no increase in the MIC. In this follow-up study, we demonstrate that DAP tolerance in the pitA6 mutant is not triggered by the accumulation of polyP. Transcriptome analysis revealed that 234 genes were at least 2.0-fold differentially expressed in the mutant. Particularly, genes involved in protein biosynthesis, carbohydrate and lipid metabolism, and replication and maintenance of DNA were downregulated. However, the most important change was the upregulation of the dlt operon, which is induced by the accumulation of intracellular Pi The GraXRS system, known as an activator of the dlt operon (d-alanylation of teichoic acids) and of the mprF gene (multiple peptide resistance factor), is not involved in DAP tolerance of the pitA6 mutant. In conclusion, DAP tolerance of the pitA6 mutant is due to an upregulation of the dlt operon, triggered directly or indirectly by the accumulation of Pi. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  20. An investigation of the effect of pit latrine additives on VIP latrine ...

    African Journals Online (AJOL)

    Manufacturers of various commercial pit latrine additives claim that by addition of this product to pit content, accumulation rate and pit content volume can be reduced, thereby preventing the pit from ever reaching capacity. This paper presents a comprehensive study conducted to determine the effects of additives on pit ...

  1. 241-AY-102 Leak Detection Pit Drain Line Inspection Report

    International Nuclear Information System (INIS)

    Boomer, Kayle D.; Engeman, Jason K.; Gunter, Jason R.; Joslyn, Cameron C.; Vazquez, Brandon J.; Venetz, Theodore J.; Garfield, John S.

    2014-01-01

    This document provides a description of the design components, operational approach, and results from the Tank AY-102 leak detection pit drain piping visual inspection. To perform this inspection a custom robotic crawler with a deployment device was designed, built, and operated by IHI Southwest Technologies, Inc. for WRPS to inspect the 6-inch leak detection pit drain line

  2. Establishing Ground Vibration Threshold Level for Open Pit Mining ...

    African Journals Online (AJOL)

    To assess the impact of blasting activities on building structures in open pit mining districts in Ghana a study was carried out in Prestea, a township very close to the perimeter of the Plant North pit of the Bogoso Gold Ltd (now Golden Star Resources Bogoso/Prestea Mines), in the Western Region of Ghana. It was observed ...

  3. Sustainable Environmental Protection Using Modified Pit-Latrines

    NARCIS (Netherlands)

    Chaggu, E.J.

    2004-01-01

    Pit-latrines are on-site excreta disposal facilities widely used as anaerobic accumulation system for stabilizing human wastes like excreta, both in rural and urban settlements of developing countries. Flooding of pit-latrines is often a common phenomenon, especially in situations of high water

  4. Modelling the filling rate of pit latrines | Brouckaert | Water SA

    African Journals Online (AJOL)

    Excreta (faeces and urine) that are deposited into a pit latrine are subject to biodegradation, which substantially reduces the volume that remains. On the other hand, other matter that is not biodegradable usually finds itsway into pit latrines. The net filling rate is thus dependent on both the rate of addition of material and its ...

  5. 241-AY-102 Leak Detection Pit Drain Line Inspection Report

    Energy Technology Data Exchange (ETDEWEB)

    Boomer, Kayle D. [Hanford Site (HNF), Richland, WA (United States); Engeman, Jason K. [Hanford Site (HNF), Richland, WA (United States); Gunter, Jason R. [Hanford Site (HNF), Richland, WA (United States); Joslyn, Cameron C. [Hanford Site (HNF), Richland, WA (United States); Vazquez, Brandon J. [Hanford Site (HNF), Richland, WA (United States); Venetz, Theodore J. [Hanford Site (HNF), Richland, WA (United States); Garfield, John S. [AEM Consulting, Richland, WA (United States)

    2014-01-20

    This document provides a description of the design components, operational approach, and results from the Tank AY-102 leak detection pit drain piping visual inspection. To perform this inspection a custom robotic crawler with a deployment device was designed, built, and operated by IHI Southwest Technologies, Inc. for WRPS to inspect the 6-inch leak detection pit drain line.

  6. Pit membranes of Ephedra resemble gymnosperms more than angiosperms

    Science.gov (United States)

    Roland Dute; Lauren Bowen; Sarah Schier; Alexa Vevon; Troy Best; Maria Auad; Thomas Elder; Pauline Bouche; Steven Jansen

    2014-01-01

    Bordered pit pairs of Ephedra species were characterized using different types of microscopy. Pit membranes contained tori that did not stain for lignin. SEM and AFM views of the torus surface showed no plasmodesmatal openings, but branched, secondary plasmodesmata were occasionally noted using TEM in conjunction with ultrathin sections. The margo consisted of radial...

  7. The phylogenetic significance of vestured pits in Boraginaceae

    NARCIS (Netherlands)

    Rabaey, D.; Lens, F.; Smets, E.; Jansen, S.

    2010-01-01

    The bordered pit structure in tracheary elements of 105 Boraginaceae species is studied using scanning electron microscopy to examine the systematic distribution of vestured pits. Forty-three species out of 16 genera show a uniform presence of this feature throughout their secondary xylem. Most

  8. Analysis of two Pit-1 gene polymorphisms: Single nucleotide ...

    African Journals Online (AJOL)

    Pit-1 is a pituitary-specific transcription factor responsible for pituitary development and hormone expression in mammals. Pit-1 is a member of the POU domain containing proteins, a group of transcriptional regulators with a critical role in cell differentiation and proliferation. It was shown that this group of proteins control the ...

  9. Construction of the KUT test pits

    International Nuclear Information System (INIS)

    Knapp, K.E.; Bush, W.E.

    1976-09-01

    Models are required to calibrate spectral logging systems to differentiate between U, Th, and K (''KUT''), in order to determine the grade of low-grade U deposits. The models were constructed by excavating three pits, emplacing three form tanks (11 ft long, 4 ft dia culvert) with 4-in. dia central holes, and pouring the following zones: 3-ft concrete lower barren zone, a 5-ft ore zone, and a final 3-ft upper barren zone. The U ore zone comprised 0.33 percent U 3 O 8 Climax ore, sand, cement, and water; the Th ore zone comprised monazite sands, plaster sand, cement, and water; and the K ore zone comprised feldspar, cement, and water. Form pipes were used to form the central holes. Analyses were made of samples taken from the zones

  10. 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.

  11. Stochastic models for predicting pitting corrosion damage of HLRW containers

    International Nuclear Information System (INIS)

    Henshall, G.A.

    1991-10-01

    Stochastic models for predicting aqueous pitting corrosion damage of high-level radioactive-waste containers are described. These models could be used to predict the time required for the first pit to penetrate a container and the increase in the number of breaches at later times, both of which would be useful in the repository system performance analysis. Monte Carlo implementations of the stochastic models are described, and predictions of induction time, survival probability and pit depth distributions are presented. These results suggest that the pit nucleation probability decreases with exposure time and that pit growth may be a stochastic process. The advantages and disadvantages of the stochastic approach, methods for modeling the effects of environment, and plans for future work are discussed

  12. Method for Identifying Lava Tubes Among Pit Craters Using Brightness Profile Across Pits on the Moon or Mars

    Directory of Open Access Journals (Sweden)

    Jongil Jung

    2016-03-01

    Full Text Available Caves can serve as major outposts for future human exploration of the Moon and Mars. In addition, caves can protect people and electronic equipment from external hazards such as cosmic ray radiation and meteorites impacts and serve as a shelter. Numerous pit craters have been discovered on the Moon and Mars and are potential entrances to caves; the principal topographic features of pit craters are their visible internal floors and pits with vertical walls. We have devised two topographical models for investigating the relationship between the topographical characteristics and the inner void of pit craters. One of our models is a concave floor void model and the other is a convex floor tube model. For each model, optical photographs have been obtained under conditions similar to those in which optical photographs have been acquired for craters on the Moon and Mars. Brightness profiles were analyzed for determining the profile patterns of the void pit craters. The profile patterns were compared to the brightness profiles of Martian pit craters, because no good-quality images of lunar pit craters were available. In future studies, the model profile patterns will be compared to those of lunar pit craters, and the proposed method will likely become useful for finding lunar caves and consequently for planning lunar bases for manned lunar expeditions.

  13. Fecal indicator and Ascaris removal from double pit latrine content.

    Science.gov (United States)

    Dey, Digbijoy; Ridwanul Haque, A T M; Kabir, Babar; Ubaid, Sharmin Farhat

    2016-12-01

    Since May 2006, the BRAC Water, Sanitation and Hygiene (WASH) Programme in Bangladesh has enabled more than 30 million people to achieve hygienic sanitation, contributing to an increase in sanitation coverage from 33 to 83% in programme areas and rapid progress towards universal access. In rural areas, most families have single pit latrines that need to be emptied when full. Since 2007, BRAC has promoted the use of hygienic double-pit latrines. Use of double-pit latrines, where appropriate, is also recommended in the Bangladeshi Draft National Water Supply and Sanitation Strategy. More than 800,000 double-pit latrines are in use in BRAC WASH areas, delaying the need for emptying and allowing time for the fecal matter to decompose while the resting pit is sealed. This paper focuses on a study undertaken by BRAC WASH to treat and safely use fecal material from double pit latrines as an organic fertilizer for rice and other crops. The study investigated the removal of pathogens from pit waste through simple solar drying and conducted analysis on nutrient properties of fecal sludge. The study showed a significant positive impact on developing organic fertilizer from fecal sludge.

  14. Pitting corrosion of copper. An equilibrium - mass transport study

    Energy Technology Data Exchange (ETDEWEB)

    Taxen, C. [Swedish Corrosion Inst., Stockholm (Sweden)

    2002-08-01

    A mathematical model for the propagation of corrosion pits is described and used to calculate the potentials below which copper is immune to pitting. The model uses equilibrium data and diffusion coefficients and calculates the stationary concentration profiles of 26 aqueous species from the bulk water outside a corrosion pit to the site of the metal dissolution. Precipitation of oxides and salts of copper is considered. Studied conditions include water compositions from tap waters to seawater at the temperatures 25 deg C and 75 deg C. Carbonate and sulphate are aggressive towards copper because of complex formation with divalent copper. Carbonate is less aggressive in a corrosion pit than outside at the pH of the bulk. Carbonate carries acidity out from the pit, favours oxide formation and may prevent the initiation of acidic corrosion pits. The concentration profiles are used to estimate the maximum propagation rates for a corrosion pit. A high potential is found to be the most important factor for the rate of propagation. The levels of potential copper can sustain, as corrosion potentials are discussed in terms of the stability of cuprous oxide as a cathode material for oxygen reduction relative to non-conducting cupric phases.

  15. Influence of remanent magnetization on pitting corrosion in pipeline steel

    Energy Technology Data Exchange (ETDEWEB)

    Espina-Hernandez, J. H. [ESIME Zacatenco, SEPI Electronica Instituto Politecnico Nacional Mexico, D. F. (Mexico); Caleyo, F.; Hallen, J. M. [DIM-ESIQIE, Instituto Politecnico Nacional Mexico D. F. (Mexico); Lopez-Montenegro, A.; Perez-Baruch, E. [Pemex Exploracion y Produccion, Region Sur Villahermosa, Tabasco (Mexico)

    2010-07-01

    Statistical studies performed in Mexico indicate that leakage due to external pitting corrosion is the most likely cause of failure of buried pipelines. When pipelines are inspected with the magnetic flux leakage (MFL) technology, which is routinely used, the magnetization level of every part of the pipeline changes as the MFL tool travels through it. Remanent magnetization stays in the pipeline wall after inspection, at levels that may differ from a point to the next. This paper studies the influence of the magnetic field on pitting corrosion. Experiments were carried out on grade 52 steel under a level of remanent magnetization and other laboratory conditions that imitated the conditions of a pipeline after an MLF inspection. Non-magnetized control samples and magnetized samples were subjected to pitting by immersion in a solution containing chlorine and sulfide ions for seven days, and then inspected with optical microscopy. Results show that the magnetic field in the pipeline wall significantly increases pitting corrosion.

  16. Ultimate strength of stiffened plates with pitting corrosion

    Directory of Open Access Journals (Sweden)

    Ahmad Rahbar-Ranji

    2015-05-01

    Full Text Available Predicting residual strength of corroded plates is of crucial importance for service life estimation of aged structures. A series of nonlinear finite element method is employed for ultimate strength analysis of stiffened plates with pitting corrosion. Influential parameters, including plate thickness, type and size of stiffeners, pit depth and degree of pitting are varied and more than 208 finite element models are analyzed. It is found that ultimate strength is reduced by increasing pit depth to thickness ratio. Thin and intermediate plates have minimum and maximum reduction of ultimate strength with stronger stiffeners, respectively. In weak stiffener, reduction of ultimate strength in thin and intermediate plates depends on DOP. Reduction of ultimate strength in thick plates depends on thickness ofplate and DOP. For intermediate plates, reduction for all stiffeners regardless of shape and size are the same.

  17. CLPX-Ground: ISA Snow Pit Measurements, Version 2

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set consists of snow pit data from nine study areas, within three larger-scale areas in northern Colorado (Fraser, North Park, and Rabbit Ears Meso-cell...

  18. Studies in pitting corrosion on archaeological bronzes. Copper

    International Nuclear Information System (INIS)

    Bresle, Aa.; Saers, J.; Arrhenius, B.

    1983-01-01

    Copper has been proposed as a canister material for use in the long-term storage of radioactive waste from nuclear power reactors. The storage period has been set to at least 100 000 years, during which time the copper cylinders must remain intact so that the contained waste has no possibility of leaking out. In this work, the pitting factor in archaelogical copper objects have been determined. The absolute values of the pitting factor obtained are generally very low. In the case of the most thoroughly studied material the pitting factor is only slightly more than three units. Nor does the native copper, with a presumed burial period of about 8000 years, exhibit particularly high values. In summary, it can therefore be concluded that the present study does not provide support for the assumption of extremely high pitting factors in copper-base material that has been buried for periods of several millenia. (G.B.)

  19. South Pole Snow Pit, 1988 and 1989, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — Information from 6-meter snow pits dug close to the South Pole in austral summer 1988-1989 by the Glacier Research Group of the University of New Hampshire (location...

  20. Numerical Simulation of Material Strength Deterioration due to Pitting Corrosion

    OpenAIRE

    Kolios, Athanasios J.; Srikanth, Sumant; Salonitis, Konstantinos

    2014-01-01

    Pitting corrosion is an insidious form of localized corrosion affecting characteristics of various engineering metallic alloys. Currently very limited literature exists with regard to systematic characterization of pitted surfaces or the efficient use of numerical methods to assess its effect, i.e. fatigue life reduction caused by the state of a corroded specimen and particularly through the study of stress concentrations considering the geometrical anomalies introduced to a surface. Much of ...

  1. Ecological geology environmental assessment of open-pit mines

    International Nuclear Information System (INIS)

    Dong Shuangfa; Jiang Xue

    2010-01-01

    In this paper, there is a detail description of ecological geology environmental assessment of open-pit mines, including method, process and results. We took ecological geology environmental assessment work on the base of the results of some open-pit mines such as extremely low content magnetite in Hebei Province, inducted and summarized the ecological geology environment quality. The results are reasonable. It provides basic data for the second mines programming in Hebei Province. (authors)

  2. New diagnostic technology and hidden pits and fissures caries

    OpenAIRE

    Fabrizio Guerra; Marta Mazur; Francesca Rinaldo; Denise Corridore; Daniele Salvi; Debora Pasqualotto; Gianna Maria Nardi; Livia Ottolenghi

    2015-01-01

    The accuracy in pits and fissures caries detection is of paramount importance in dental caries primary and secondary prevention. A combination of visual examination and probing is currently the mainstay of occlusal caries diagnosis. Unfortunately, these types of inspection alone may leave a certain number of pit and fissure caries undetected. The Vista Cam iX fluorescence camera (Durr Dental, Bietigheim-Bissingen, Germany) is a novel dental diagnostic tool for quantitative assessment of denta...

  3. Force-displacement measurements of earlywood bordered pits using a mesomechanical tester

    Science.gov (United States)

    Samuel L. Zelinka; Keith J. Bourne; John C. Hermanson; Samuel V. Glass; Adriana Costa; Alex C. Wiedenhoeft

    2015-01-01

    The elastic properties of pit membranes are reported to have important implications in understanding air-seeding phenomena in gymnosperms, and pit aspiration plays a large role in wood technological applications such as wood drying and preservative treatment. Here we present force–displacement measurements for pit membranes of circular bordered pits, collected on a...

  4. Deterministic chaos in the pitting phenomena of passivable alloys

    International Nuclear Information System (INIS)

    Hoerle, Stephane

    1998-01-01

    It was shown that electrochemical noise recorded in stable pitting conditions exhibits deterministic (even chaotic) features. The occurrence of deterministic behaviors depend on the material/solution severity. Thus, electrolyte composition ([Cl - ]/[NO 3 - ] ratio, pH), passive film thickness or alloy composition can change the deterministic features. Only one pit is sufficient to observe deterministic behaviors. The electrochemical noise signals are non-stationary, which is a hint of a change with time in the pit behavior (propagation speed or mean). Modifications of electrolyte composition reveals transitions between random and deterministic behaviors. Spontaneous transitions between deterministic behaviors of different features (bifurcation) are also evidenced. Such bifurcations enlighten various routes to chaos. The routes to chaos and the features of chaotic signals allow to suggest the modeling (continuous and discontinuous models are proposed) of the electrochemical mechanisms inside a pit, that describe quite well the experimental behaviors and the effect of the various parameters. The analysis of the chaotic behaviors of a pit leads to a better understanding of propagation mechanisms and give tools for pit monitoring. (author) [fr

  5. Statistical characterization of pitting corrosion process and life prediction

    International Nuclear Information System (INIS)

    Sheikh, A.K.; Younas, M.

    1995-01-01

    In order to prevent corrosion failures of machines and structures, it is desirable to know in advance when the corrosion damage will take place, and appropriate measures are needed to mitigate the damage. The corrosion predictions are needed both at development as well as operational stage of machines and structures. There are several forms of corrosion process through which varying degrees of damage can occur. Under certain conditions these corrosion processes at alone and in other set of conditions, several of these processes may occur simultaneously. For a certain type of machine elements and structures, such as gears, bearing, tubes, pipelines, containers, storage tanks etc., are particularly prone to pitting corrosion which is an insidious form of corrosion. The corrosion predictions are usually based on experimental results obtained from test coupons and/or field experiences of similar machines or parts of a structure. Considerable scatter is observed in corrosion processes. The probabilities nature and kinetics of pitting process makes in necessary to use statistical method to forecast the residual life of machine of structures. The focus of this paper is to characterization pitting as a time-dependent random process, and using this characterization the prediction of life to reach a critical level of pitting damage can be made. Using several data sets from literature on pitting corrosion, the extreme value modeling of pitting corrosion process, the evolution of the extreme value distribution in time, and their relationship to the reliability of machines and structure are explained. (author)

  6. The VIMOS Public Extragalactic Redshift Survey (VIPERS). An unprecedented view of galaxies and large-scale structure at 0.5 < z < 1.2

    Science.gov (United States)

    Guzzo, L.; Scodeggio, M.; Garilli, B.; Granett, B. R.; Fritz, A.; Abbas, U.; Adami, C.; Arnouts, S.; Bel, J.; Bolzonella, M.; Bottini, D.; Branchini, E.; Cappi, A.; Coupon, J.; Cucciati, O.; Davidzon, I.; De Lucia, G.; de la Torre, S.; Franzetti, P.; Fumana, M.; Hudelot, P.; Ilbert, O.; Iovino, A.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; Marulli, F.; McCracken, H. J.; Paioro, L.; Peacock, J. A.; Polletta, M.; Pollo, A.; Schlagenhaufer, H.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zamorani, G.; Zanichelli, A.; Burden, A.; Di Porto, C.; Marchetti, A.; Marinoni, C.; Mellier, Y.; Moscardini, L.; Nichol, R. C.; Percival, W. J.; Phleps, S.; Wolk, M.

    2014-06-01

    We describe the construction and general features of VIPERS, the VIMOS Public Extragalactic Redshift Survey. This ESO Large Programme is using the Very Large Telescope with the aim of building a spectroscopic sample of ~ 100 000 galaxies with iABcontamination is found to be only 3.2%, endorsing the quality of the star-galaxy separation process and fully confirming the original estimates based on the VVDS data, which also indicate a galaxy incompleteness from this process of only 1.4%. Using a set of 1215 repeated observations, we estimate an rms redshift error σz/ (1 + z) = 4.7 × 10-4 and calibrate the internal spectral quality grading. Benefiting from the combination of size and detailed sampling of this dataset, we conclude by presenting a map showing in unprecedented detail the large-scale distribution of galaxies between 5 and 8 billion years ago. Based on observations collected at the European Southern Observatory, Cerro Paranal, Chile, using the Very Large Telescope under programmes 182.A-0886 and partly 070.A-9007. Also based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT), which is operated by the National Research Council (NRC) of Canada, the Institut National des Sciences de l'Univers of the Centre National de la Recherche Scientifique (CNRS) of France, and the University of Hawaii. This work is based in part on data products produced at TERAPIX and the Canadian Astronomy Data Centre as part of the Canada-France-Hawaii Telescope Legacy Survey, a collaborative project of NRC and CNRS. The VIPERS website is http://www.vipers.inaf.it/

  7. The VIMOS Public Extragalactic Redshift Survey (VIPERS). Downsizing of the blue cloud and the influence of galaxy size on mass quenching over the last eight billion years

    Science.gov (United States)

    Haines, C. P.; Iovino, A.; Krywult, J.; Guzzo, L.; Davidzon, I.; Bolzonella, M.; Garilli, B.; Scodeggio, M.; Granett, B. R.; de la Torre, S.; De Lucia, G.; Abbas, U.; Adami, C.; Arnouts, S.; Bottini, D.; Cappi, A.; Cucciati, O.; Franzetti, P.; Fritz, A.; Gargiulo, A.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; Marulli, F.; Moutard, T.; Polletta, M.; Pollo, A.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Zamorani, G.; Bel, J.; Branchini, E.; Coupon, J.; Ilbert, O.; Moscardini, L.; Peacock, J. A.; Siudek, M.

    2017-08-01

    We use the full VIPERS redshift survey in combination with SDSS-DR7 to explore the relationships between star-formation history (using d4000), stellar mass and galaxy structure, and how these relationships have evolved since z 1. We trace the extents and evolutions of both the blue cloud and red sequence by fitting double Gaussians to the d4000 distribution of galaxies in narrow stellar mass bins, for four redshift intervals over 0 1011M⊙, d4000 parallel, their structures change, showing higher Sérsic indices and central stellar mass densities. For these galaxies, bulge growth is required for them to reach the high-mass limit of the blue cloud and be quenched by internal mechanisms. The blue-cloud galaxies that are being quenched at z 0.8 lie along the same size-mass relation as present day quiescent galaxies and seem the likely progenitors of today's S0s. Based on observations collected at the European Southern Observatory, Cerro Paranal, Chile, using the Very Large Telescope under programs 182.A-0886 and partly 070.A-9007. Also based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT), which is operated by the National Research Council (NRC) of Canada, the Institut National des Sciences de l'Univers of the Centre National de la Recherche Scientifique (CNRS) of France, and the University of Hawaii. This work is based in part on data products produced at TERAPIX and the Canadian Astronomy Data Centre as part of the Canada-France-Hawaii Telescope Legacy Survey, a collaborative project of NRC and CNRS. The VIPERS web site is http://www.vipers.inaf.it/

  8. Nobody’s perfect: Can irregularities in pit structure influence vulnerability to cavitation?

    Directory of Open Access Journals (Sweden)

    Lenka ePlavcová

    2013-11-01

    Full Text Available Recent studies have suggested that species-specific pit properties such as pit membrane thickness, pit membrane porosity, torus-to-aperture diameter ratio and pit chamber depth influence xylem vulnerability to cavitation. Despite the indisputable importance of using mean pit characteristics, considerable variability in pit structure within a single species or even within a single pit field should be acknowledged. According to the rare pit hypothesis, a single pit that is more air-permeable than many neighboring pits is sufficient to allow air-seeding. Therefore, any irregularities or morphological abnormalities in pit structure allowing air-seeding should be associated with increased vulnerability to cavitation. Considering the currently proposed models of air-seeding, pit features such as rare, large pores in the pit membrane, torus extensions, and plasmodesmatal pores in a torus can represent potential glitches. These aberrations in pit structure could either result from inherent developmental flaws, or from damage caused to the pit membrane by chemical and physical agents. This suggests the existence of interesting feedbacks between abiotic and biotic stresses in xylem physiology.

  9. Nobody's perfect: can irregularities in pit structure influence vulnerability to cavitation?

    Science.gov (United States)

    Plavcová, Lenka; Jansen, Steven; Klepsch, Matthias; Hacke, Uwe G

    2013-01-01

    Recent studies have suggested that species-specific pit properties such as pit membrane thickness, pit membrane porosity, torus-to-aperture diameter ratio and pit chamber depth influence xylem vulnerability to cavitation. Despite the indisputable importance of using mean pit characteristics, considerable variability in pit structure within a single species or even within a single pit field should be acknowledged. According to the rare pit hypothesis, a single pit that is more air-permeable than many neighboring pits is sufficient to allow air-seeding. Therefore, any irregularities or morphological abnormalities in pit structure allowing air-seeding should be associated with increased vulnerability to cavitation. Considering the currently proposed models of air-seeding, pit features such as rare, large pores in the pit membrane, torus extensions, and plasmodesmatal pores in a torus can represent potential glitches. These aberrations in pit structure could either result from inherent developmental flaws, or from damage caused to the pit membrane by chemical and physical agents. This suggests the existence of interesting feedbacks between abiotic and biotic stresses in xylem physiology.

  10. Characterization of transport mechanisms and determinants critical for Na+-dependent Pi symport of the PiT family paralogs human PiT1 and PiT2

    DEFF Research Database (Denmark)

    Bøttger, Pernille; Hede, Susanne E; Grunnet, Morten

    2006-01-01

    The general phosphate need in mammalian cells is accommodated by members of the P(i) transport (PiT) family (SLC20), which use either Na(+) or H(+) to mediate inorganic phosphate (P(i)) symport. The mammalian PiT paralogs PiT1 and PiT2 are Na(+)-dependent P(i) (NaP(i)) transporters...... and are exploited by a group of retroviruses for cell entry. Human PiT1 and PiT2 were characterized by expression in Xenopus laevis oocytes with (32)P(i) as a traceable P(i) source. For PiT1, the Michaelis-Menten constant for P(i) was determined as 322.5 +/- 124.5 microM. PiT2 was analyzed for the first time...... and showed positive cooperativity in P(i) uptake with a half-maximal activity constant for P(i) of 163.5 +/- 39.8 microM. PiT1- and PiT2-mediated Na(+)-dependent P(i) uptake functions were not significantly affected by acidic and alkaline pH and displayed similar Na(+) dependency patterns. However, only PiT2...

  11. Ion induced changes in the structure of bordered pit membranes

    Directory of Open Access Journals (Sweden)

    Jinkee eLee

    2012-03-01

    Full Text Available Xylem hydraulic resistance varies with ion concentration in sap solution. It is assumed that this variation in resistance results from hydrogel like properties of pectins located in bordered pit membranes separating adjacent vessels. Although kinetics of the resistance change suggests swelling/deswelling behavior of the pectins, there is no direct evidence of this activity. In this report we provide evidence of structural changes in bordered pit membranes responding to variation in ionic concentration of solute around it using atomic force microscopy (AFM. AFM revealed bordered pit membranes as relatively smooth, soft and lacking any sharp edges surface when submerged in de-ionized water, in contrast to pictures from scanning electron microscope (SEM or AFM performed on air dry material. Exposure of the bordered pit membranes to 50 mM KCl solution resulted in significant changes in both surface physical properties with and elevation features as bordered pit membrane became harder, with visible edges of fibers and collapsed, while no change in porosity was observed. Analysis suggests a need for a major shift in our understanding to the physical bases of variable xylem resistance from change in porosity to change in pathway length. Findings support the role of actuating properties of hybrid hydrogel-cellulose materials in water redistribution and embolism resistance.

  12. Fukushima Nuclear Accident Recorded in Tibetan Plateau Snow Pits

    Science.gov (United States)

    Wang, Ninglian; Wu, Xiaobo; Kehrwald, Natalie; Li, Zhen; Li, Quanlian; Jiang, Xi; Pu, Jianchen

    2015-01-01

    The β radioactivity of snow-pit samples collected in the spring of 2011 on four Tibetan Plateau glaciers demonstrate a remarkable peak in each snow pit profile, with peaks about ten to tens of times higher than background levels. The timing of these peaks suggests that the high radioactivity resulted from the Fukushima nuclear accident that occurred on March 11, 2011 in eastern Japan. Fallout monitoring studies demonstrate that this radioactive material was transported by the westerlies across the middle latitudes of the Northern Hemisphere. The depth of the peak β radioactivity in each snow pit compared with observational precipitation records, suggests that the radioactive fallout reached the Tibetan Plateau and was deposited on glacier surfaces in late March 2011, or approximately 20 days after the nuclear accident. The radioactive fallout existed in the atmosphere over the Tibetan Plateau for about one month. PMID:25658094

  13. Fukushima nuclear accident recorded in Tibetan Plateau snow pits.

    Directory of Open Access Journals (Sweden)

    Ninglian Wang

    Full Text Available The β radioactivity of snow-pit samples collected in the spring of 2011 on four Tibetan Plateau glaciers demonstrate a remarkable peak in each snow pit profile, with peaks about ten to tens of times higher than background levels. The timing of these peaks suggests that the high radioactivity resulted from the Fukushima nuclear accident that occurred on March 11, 2011 in eastern Japan. Fallout monitoring studies demonstrate that this radioactive material was transported by the westerlies across the middle latitudes of the Northern Hemisphere. The depth of the peak β radioactivity in each snow pit compared with observational precipitation records, suggests that the radioactive fallout reached the Tibetan Plateau and was deposited on glacier surfaces in late March 2011, or approximately 20 days after the nuclear accident. The radioactive fallout existed in the atmosphere over the Tibetan Plateau for about one month.

  14. Congenital upper lip pit: A rare case report

    Directory of Open Access Journals (Sweden)

    Leena James

    2015-01-01

    Full Text Available One of the rarest developmental malformations of the lip is congenital lip pits. They are usually seen as bilateral depressions in the vermilion zone of the lip and occur on the paramedian portion of the vermilion border of the lip. They are extremely rare in the upper lip. Lip pits are due to the failure of complete union of embryonic lateral sulci of the lip/notching of lip at an early stage of development with fixation of tissues of the base of the notch. Lip pits have also been associated with a variety of other congenital disorders and other malformations. The clinical and pathologic picture and the therapeutic aspects of this condition are discussed in this paper.

  15. Pit Distribution Design for Computer-Generated Waveguide Holography

    Science.gov (United States)

    Yagi, Shogo; Imai, Tadayuki; Ueno, Masahiro; Ohtani, Yoshimitsu; Endo, Masahiro; Kurokawa, Yoshiaki; Yoshikawa, Hiroshi; Watanabe, Toshifumi; Fukuda, Makoto

    2008-02-01

    Multilayered waveguide holography (MWH) is one of a number of page-oriented data multiplexing holographies that will be applied to optical data storage and three-dimensional (3D) moving images. While conventional volumetric holography using photopolymer or photorefractive materials requires page-by-page light exposure for recording, MWH media can be made by employing stamping and laminating technologies that are suitable for mass production. This makes devising an economical mastering technique for replicating holograms a key issue. In this paper, we discuss an approach to pit distribution design that enables us to replace expensive electron beam mastering with economical laser beam mastering. We propose an algorithm that avoids the overlapping of even comparatively large adjacent pits when we employ laser beam mastering. We also compensate for the angular dependence of the diffraction power, which strongly depends on pit shape, by introducing an enhancement profile so that a diffracted image has uniform intensity.

  16. 200 West Ash Pit Demolition Site closure plan

    International Nuclear Information System (INIS)

    1992-11-01

    The Hanford Facility is owned by the US Government and operated by the US Department of Energy, Richland Field Office. Dangerous waste and mixed waste (containing both radioactive and dangerous components) are managed and produced on the Hanford Facility. Westinghouse Hanford Company is a major contractor to the US Department of Energy, Richland Field Office and serves as cooperator of the 200 West Ash Pit Demolition Site, the unit addressed in this closure plan. The 200 West Ash Pit Demolition Site Closure Plan consists of a Part A Permit Application (Revision 3) and a closure plan. An explanation of the Part A Permit Application revision is provided at the beginning of the Part A section. The closure plan consists of nine chapters and three appendices. This 200 West Ash Pit Demolition Site Closure Plan submittal contains information current as of October 15, 1992

  17. State Waste Discharge Permit application: 200-W Powerhouse Ash Pit

    Energy Technology Data Exchange (ETDEWEB)

    Atencio, B.P.

    1994-06-01

    As part of the Hanford Federal Facility Agreement and Consent Order negotiations; the US Department of Energy, Richland Operations Office, the US Environmental Protection Agency, and the Washington State Department of Ecology agreed that liquid effluent discharges to the ground on the Hanford Site which affect groundwater or have the potential to affect groundwater would be subject to permitting under the structure of Chapter 173-216 (or 173-218 where applicable) of the Washington Administrative Code, the State Waste Discharge Permit Program. This document constitutes the State Waste Discharge Permit application for the 200-W Powerhouse Ash Pit. The 200-W Powerhouse Ash Waste Water discharges to the 200-W Powerhouse Ash Pit via dedicated pipelines. The 200-W Powerhouse Ash Waste Water is the only discharge to the 200-W Powerhouse Ash Pit. The 200-W Powerhouse is a steam generation facility consisting of a coal-handling and preparation section and boilers.

  18. State Waste Discharge Permit application: 200-E Powerhouse Ash Pit

    Energy Technology Data Exchange (ETDEWEB)

    Atencio, B.P.

    1994-06-01

    As part of the Hanford Federal Facility Agreement and Consent Order negotiations, the US Department and Energy, Richland Operations Office, the US Environmental Protection Agency, and the Washington State Department of Ecology agreed that liquid effluent discharges to the ground on the Hanford Site which affect groundwater or have the potential to affect groundwater would be subject to permitting under the structure of Chapter 173-216 (or 173-218 where applicable) of the Washington Administrative Code, the State Waste Discharge Permit Program. This document constitutes the State Waste Discharge Permit application for the 200-E Powerhouse Ash Pit. The 200-E Powerhouse Ash Waste Water discharges to the 200-E Powerhouse Ash Pit via dedicated pipelines. The 200-E Ash Waste Water is the only discharge to the 200-E Powerhouse Ash Pit. The 200-E Powerhouse is a steam generation facility consisting of a coal-handling and preparation section and boilers.

  19. Detection of Pitting in Gears Using a Deep Sparse Autoencoder

    Directory of Open Access Journals (Sweden)

    Yongzhi Qu

    2017-05-01

    Full Text Available In this paper; a new method for gear pitting fault detection is presented. The presented method is developed based on a deep sparse autoencoder. The method integrates dictionary learning in sparse coding into a stacked autoencoder network. Sparse coding with dictionary learning is viewed as an adaptive feature extraction method for machinery fault diagnosis. An autoencoder is an unsupervised machine learning technique. A stacked autoencoder network with multiple hidden layers is considered to be a deep learning network. The presented method uses a stacked autoencoder network to perform the dictionary learning in sparse coding and extract features from raw vibration data automatically. These features are then used to perform gear pitting fault detection. The presented method is validated with vibration data collected from gear tests with pitting faults in a gearbox test rig and compared with an existing deep learning-based approach.

  20. The VIMOS Public Extragalactic Redshift Survey (VIPERS):. A quiescent formation of massive red-sequence galaxies over the past 9 Gyr

    Science.gov (United States)

    Fritz, A.; Scodeggio, M.; Ilbert, O.; Bolzonella, M.; Davidzon, I.; Coupon, J.; Garilli, B.; Guzzo, L.; Zamorani, G.; Abbas, U.; Adami, C.; Arnouts, S.; Bel, J.; Bottini, D.; Branchini, E.; Cappi, A.; Cucciati, O.; De Lucia, G.; de la Torre, S.; Franzetti, P.; Fumana, M.; Granett, B. R.; Iovino, A.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; Marulli, F.; McCracken, H. J.; Paioro, L.; Polletta, M.; Pollo, A.; Schlagenhaufer, H.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Burden, A.; Di Porto, C.; Marchetti, A.; Marinoni, C.; Mellier, Y.; Moscardini, L.; Nichol, R. C.; Peacock, J. A.; Percival, W. J.; Phleps, S.; Wolk, M.

    2014-03-01

    We explore the evolution of the colour-magnitude relation (CMR) and luminosity function (LF) at 0.4 contamination varies for the different methods and with redshift, but regardless of the method we measure a consistent evolution of the red-sequence (RS). Between 0.4 1011 M⊙) and expeditious RS formation over a short period of ~1.5 Gyr starting before z = 1. This is supported by the detection of ongoing SF in early-type galaxies at 0.9 Chile, using the Very Large Telescope under programs 182.A-0886 and partly 070.A-9007. Also based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT), which is operated by the National Research Council (NRC) of Canada, the Institut National des Sciences de l'Univers of the Centre National de la Recherche Scientifique (CNRS) of France, and the University of Hawaii. This work is based in part on data products produced at TERAPIX and the Canadian Astronomy Data Centre as part of the Canada-France-Hawaii Telescope Legacy Survey, a collaborative project of NRC and CNRS. The VIPERS website is http://www.vipers.inaf.it/.Appendices are available in electronic form at http://www.aanda.org

  1. Nuclear markers support the mitochondrial phylogeny of Vipera ursinii-renardi complex (Squamata: Viperidae) and species status for the Greek meadow viper.

    Science.gov (United States)

    Mizsei, Edvárd; Jablonski, Daniel; Roussos, Stephanos A; Dimaki, Maria; Ioannidis, Yannis; Nilson, Göran; Nagy, Zoltán T

    2017-01-31

    Meadow vipers (Vipera ursinii-renardi complex) are small-bodied snakes that live in either lowland grasslands or montane subalpine-alpine meadows spanning a distribution from France to western China. This complex has previously been the focus of several taxonomic studies which were based mainly on morphological, allozyme or immunological characters and did not clearly resolve the relationships between the various taxa. Recent mitochondrial DNA analyses found unexpected relationships within the complex which had taxonomical consequences for the detected lineages. The most surprising was the basal phylogenetic position of Vipera ursinii graeca, a taxon described almost 30 years ago from the mountains of Greece. We present here new analyses of three nuclear markers (BDNF, NT3, PRLR; a first for studies of meadow and steppe vipers) as well as analyses of newly obtained mitochondrial DNA sequences (CYT B, ND4).Our Bayesian analyses of nuclear sequences are concordant with previous studies of mitochondrial DNA, in that the phylogenetic position of the graeca clade is a clearly distinguished and distinct lineage separated from all other taxa in the complex. These phylogenetic results are also supported by a distinct morphology, ecology and isolated distribution of this unique taxon. Based on several data sets and an integrative species concept we recommend to elevate this taxon to species level: Vipera graeca Nilson & Andrén, 1988 stat. nov.

  2. Relationship between foveal cone specialization and pit morphology in albinism.

    Science.gov (United States)

    Wilk, Melissa A; McAllister, John T; Cooper, Robert F; Dubis, Adam M; Patitucci, Teresa N; Summerfelt, Phyllis; Anderson, Jennifer L; Stepien, Kimberly E; Costakos, Deborah M; Connor, Thomas B; Wirostko, William J; Chiang, Pei-Wen; Dubra, Alfredo; Curcio, Christine A; Brilliant, Murray H; Summers, C Gail; Carroll, Joseph

    2014-05-20

    Albinism is associated with disrupted foveal development, though intersubject variability is becoming appreciated. We sought to quantify this variability, and examine the relationship between foveal cone specialization and pit morphology in patients with a clinical diagnosis of albinism. We recruited 32 subjects with a clinical diagnosis of albinism. DNA was obtained from 25 subjects, and known albinism genes were analyzed for mutations. Relative inner and outer segment (IS and OS) lengthening (fovea-to-perifovea ratio) was determined from manually segmented spectral domain-optical coherence tomography (SD-OCT) B-scans. Foveal pit morphology was quantified for eight subjects from macular SD-OCT volumes. Ten subjects underwent imaging with adaptive optics scanning light ophthalmoscopy (AOSLO), and cone density was measured. We found mutations in 22 of 25 subjects, including five novel mutations. All subjects lacked complete excavation of inner retinal layers at the fovea, though four subjects had foveal pits with normal diameter and/or volume. Peak cone density and OS lengthening were variable and overlapped with that observed in normal controls. A fifth hyper-reflective band was observed in the outer retina on SD-OCT in the majority of the subjects with albinism. Foveal cone specialization and pit morphology vary greatly in albinism. Normal cone packing was observed in the absence of a foveal pit, suggesting a pit is not required for packing to occur. The degree to which retinal anatomy correlates with genotype or visual function remains unclear, and future examination of larger patient groups will provide important insight on this issue. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  3. Relationship Between Foveal Cone Specialization and Pit Morphology in Albinism

    Science.gov (United States)

    Wilk, Melissa A.; McAllister, John T.; Cooper, Robert F.; Dubis, Adam M.; Patitucci, Teresa N.; Summerfelt, Phyllis; Anderson, Jennifer L.; Stepien, Kimberly E.; Costakos, Deborah M.; Connor, Thomas B.; Wirostko, William J.; Chiang, Pei-Wen; Dubra, Alfredo; Curcio, Christine A.; Brilliant, Murray H.; Summers, C. Gail; Carroll, Joseph

    2014-01-01

    Purpose. Albinism is associated with disrupted foveal development, though intersubject variability is becoming appreciated. We sought to quantify this variability, and examine the relationship between foveal cone specialization and pit morphology in patients with a clinical diagnosis of albinism. Methods. We recruited 32 subjects with a clinical diagnosis of albinism. DNA was obtained from 25 subjects, and known albinism genes were analyzed for mutations. Relative inner and outer segment (IS and OS) lengthening (fovea-to-perifovea ratio) was determined from manually segmented spectral domain-optical coherence tomography (SD-OCT) B-scans. Foveal pit morphology was quantified for eight subjects from macular SD-OCT volumes. Ten subjects underwent imaging with adaptive optics scanning light ophthalmoscopy (AOSLO), and cone density was measured. Results. We found mutations in 22 of 25 subjects, including five novel mutations. All subjects lacked complete excavation of inner retinal layers at the fovea, though four subjects had foveal pits with normal diameter and/or volume. Peak cone density and OS lengthening were variable and overlapped with that observed in normal controls. A fifth hyper-reflective band was observed in the outer retina on SD-OCT in the majority of the subjects with albinism. Conclusions. Foveal cone specialization and pit morphology vary greatly in albinism. Normal cone packing was observed in the absence of a foveal pit, suggesting a pit is not required for packing to occur. The degree to which retinal anatomy correlates with genotype or visual function remains unclear, and future examination of larger patient groups will provide important insight on this issue. PMID:24845642

  4. The Influence of Radiation on Pit Solution Chemistry as it Pertains to the Transition from Metastable to Stable Pitting in Steels

    International Nuclear Information System (INIS)

    Galuszka-Muga, Barbara; Muga, Luis M.

    2006-01-01

    Previous work relevant to current efforts is summarized. A description of an improved version of a new electrochemical probe, the ArtPit, is given. The distinct feature of the probe for investigating metastable pitting of carbon steels is specified and compared to other approaches. The electrochemical response of the ArtPit under the gamma irradiation and elevated temperature conditions that occur at high level waste (HLW) storage tanks is presented. In particular, the Tafel slope determinations and chemical analyses of the ArtPit confined volume electrolyte are described. Based on results a possible approach for reducing the corrosion rate of HLW tank walls is suggested. Additional statistical analysis of the occurrence of short duration (passivated pits) and long term (stable pitting) electrochemical pulses (current surges) during exposure confirm that radiation enhances the occurrence of both more and smaller sized pits due to increased likelihood of repassivation

  5. Interior drains for open pit disposal of uranium mill tailings

    International Nuclear Information System (INIS)

    Staub, W.P.

    1978-01-01

    A conceptualized interior drainage system is presented for reducing the environmental impact on natural groundwater by disposal of uranium mill tailings in the mined-out open pit. The evaporation/seepage ratio can be increased through the use of interior drains, long-term monitoring of groundwater quality can be eliminated, and the open pit will not require an extensive liner. Other advantages not related to groundwater are: control of fugitive dust and radon emanation during mill operations and timely reclamation after the impoundment is filled with tailings

  6. 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

  7. Microstructural evolution and pitting resistance of annealed lean duplex stainless steel UNS S32304

    International Nuclear Information System (INIS)

    Zhang Ziying; Han Dong; Jiang Yiming; Shi Chong; Li Jin

    2012-01-01

    Highlights: ► The relationship between pitting corrosion resistance and annealing temperature for UNS S32304 was systemically studied. ► The specimens annealed at 1080 °C for 1 h, quenched in water exhibit the best pitting corrosion resistance. ► The relationship between microstructural evolution and pitting resistance of annealed UNS S32304 was discussed in detail. ► The pitting corrosion resistance is consistent with pitting resistance equivalent number of weaker phase for UNS S32304 alloy. - Abstract: The effect of annealing temperature in the range from 1000 to 1200 °C on the pitting corrosion behavior of duplex stainless steel UNS S32304 was investigated by the potentiodynamic polarization and potentiostatic critical pitting temperature techniques. The microstructural evolution and pit morphologies were studied using a scanning electron microscopy with energy dispersive X-ray spectroscopy. The results demonstrated that the nucleation of metastable pits transformed from austenite phase to ferrite phase with the increasing annealing temperature. As the annealing temperature increased, the pitting corrosion resistance firstly increased and then decreased. The highest pitting corrosion resistance was obtained at 1080 °C with the highest critical pitting temperature value and pitting nucleation resistance. The results could be well explained by the microstructural evolution of ferrite and austenite phases induced by annealing treatment.

  8. Pitting Corrosion Topography Characteristics and Evolution Laws of LC4 Aluminum Alloy in Service Environment

    Directory of Open Access Journals (Sweden)

    LIU Zhiguo

    2017-08-01

    Full Text Available Aircraft aluminum alloy is easy to initiate pitting corrosion in the service environment, the pitting corrosion topography characteristics could directly affect the fatigue mechanical property of structure material. In order to obtain the pitting corrosion topography characteristics of LC4 aluminum alloy in the service environment, the accelerated corrosion test was carried out along the accelerated corrosion test environment spectrum which imitated the service environment spectrum, and the corrosion topography characteristic parameters of corrosion pit depth H,corrosion pit surface length L and corrosion pit surface width W were defined respectively. During the corrosion test process,the three parameters of typical corrosion pit were successively measured in different equivalent corrosion years for obtaining the corrosion pit damage size data, then the data were analysed through the statistics method and fractal theory. Further more in order to gain the pit topography characteristics in the same equivalent corrosion year and the topography evolution laws during different equivalent corrosion years were gained. The analysis results indicate that LC4 aluminum alloy corrosion pit topography characteristics in the service environment include the following:firstly, the pit topography characteristic parameters conform to the lognormal distributions in the same equivalent corrosion years; secondly,the pit topography characteristic parameters gradually reflect the fractal feature in accordance with the equivalent corrosion year increment, and the pits tend to be shallow, long and moderate wide topography character.

  9. A fundamental understanding of the electrochemical noise related to pitting corrosion of carbon steel

    Science.gov (United States)

    Cheng, Yufeng

    The pitting behavior of carbon steel in chloride-containing solutions was studied by the electrochemical noise technique. The semiconducting nature of the passive film formed on carbon steel was revealed as well. The initiation of metastable pits is generally indicated by a typical current and potential transient with the shape of a quick current rise and potential drop followed by a slow recovery. The potential fluctuations mainly come from the response of the electrode capacitance to pit growth charge. Only the current transients directly reflect the metastable pitting process. The potential dependence of the pit initiation rate is well illustrated by the point defect model, which assumes that pitting initiation is due to the anion-catalyzed cation vacancy condensation at the film/metal interface. Pit growth kinetics are controlled by the ohmic potential drop across the cover over the pits. The repassivation time of metastable pits is affected by the potential drop across the pit cover. A pit stabilization criterion of the ratio of peak pit current to pit radius indicates that the critical condition to maintain the stable pit growth must exceed 2 x 10-2 A cm-1 to avoid repassivation. The main role of chloride ions in pitting is to increase the chance of the breakdown of a passive film, rather than to inhibit surface repassivation. The initiation of a metastable pit will have a certain influence on subsequent pitting events in the case of high pitting activity. When the pitting activity decreases, the metastable pitting events will follow the Poisson distribution. Spectral analysis of noise data indicates that any transient having a sudden birth or a sudden death generates f-2 noise, while that without sudden change shows f -4 behavior. The roll-off frequency reflects the repassivation or growth rate of metastable pits. The noise resistance coincides with the polarization resistance only in passivity or general corrosion. For pitting, the noise resistance cannot

  10. Modeling sludge accumulation rates in lined pit latrines in slum ...

    African Journals Online (AJOL)

    Yvonne

    emptying methods include use of vacuum tankers, manual emptying and the newer use of gulpers and nibblers. ... extra vacuum pipe to be added, the price goes up by 3 to. 10 US dollars (Murungi and Van Dijk, 2014). ..... of the ideal portable pit-emptying machine. Waterlines 32:187-199. Still DA, Salisbury RH, Foxon KM, ...

  11. A critical analysis of physiochemical properties influencing pit latrine ...

    African Journals Online (AJOL)

    Abstract. Inadequate information on physiochemical properties of faecal sludge leads to inappropriate design of pit emptying devices and poor faecal sludge disposal contributing to environmental pollution. ... A sample of 300 g was sucked from each depth using a manual sampling tool and emptied into a plastic container.

  12. 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,.

  13. Cormorant predation on PIT-tagged lake fish

    DEFF Research Database (Denmark)

    Skov, Christian; Jepsen, Niels; Baktoft, Henrik

    2014-01-01

    The present study use data from recovered PIT (Passive Integrated Transponder) tags to explore species-and size-specific annual predation rates by cormorants on three common lacustrine fishes (size range 120-367 mm) in a European lake; roach (Rutilus rutilus), common bream (Abramis brama) and per...

  14. Modeling sludge accumulation rates in lined pit latrines in slum ...

    African Journals Online (AJOL)

    Modeling sludge accumulation rates in lined pit latrines in slum areas of Kampala City, Uganda. ... African Journal of Environmental Science and Technology ... methods such as open defecation and emptying into storm drainages are employed which consequently contribute to environmental and health-related challenges.

  15. Oxygen pitting failure of a bagasse boiler tube

    CSIR Research Space (South Africa)

    Heyes, AM

    2001-04-01

    Full Text Available that the pitting occurred during an idle period (a drought) due to oxygen ingress and failure to maintain a sufficient excess of the oxygen scavenger, sodium sulphite. The transverse orientation of the cracks and other factors suggest that the fatigue cracking...

  16. Bitter pit in apples: pre- and postharvest factors: A review

    Directory of Open Access Journals (Sweden)

    Tomislav Jemrić

    2016-12-01

    Full Text Available Bitter pit is a physiological disorder that significantly reduces the quality of apples. Although it has been detected since the beginning of the last century, still there is little known about the mechanism of its occurrence. According to numerous studies, bitter pit is formed as a result of calcium deficiency in the fruit. Some authors cite the high concentration of gibberellins, later in the production season, most probably caused by excessive activity of the roots, as the chief causative factor. Beside Ca, there are several factors that can also contribute to its development, like imbalance among some mineral elements (N, P, K and Mg, cultivar, rootstock, the ratio of vegetative and generative growth, post-harvest treatments and the storage methods. There are some prediction models available that can estimate the risk of bitter pit in apples, but even those are not always reliable. The aim of this review was to encompass the pre and postharvest factors which cause bitter pit and point out the directions for solving this problem.

  17. Laboratory protocols for testing the efficacy of commercial pit latrine ...

    African Journals Online (AJOL)

    additive products. Protocols were developed and tested on a range of different commercial products sold for their ability to control the rate of accumulation of pit latrine contents. The effect of commercial additives on mass loss from VIP sludge in. 300 g honey jars was compared to mass loss from similar units subjected to no ...

  18. 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

  19. Metallography of pitted aluminum-clad, depleted uranium fuel

    International Nuclear Information System (INIS)

    Nelson, D.Z.; Howell, J.P.

    1994-01-01

    The storage of aluminum-clad fuel and target materials in the L-Disassembly Basin at the Savannah River Site for more than 5 years has resulted in extensive pitting corrosion of these materials. In many cases the pitting corrosion of the aluminum clad has penetrated in the uranium metal core, resulting in the release of plutonium, uranium, cesium-137, and other fission product activity to the basin water. In an effort to characterize the extent of corrosion of the Mark 31A target slugs, two unirradiated slug assemblies were removed from basin storage and sent to the Savannah River Technology Center for evaluation. This paper presents the results of the metallography and photographic documentation of this evaluation. The metallography confirmed that pitting depths varied, with the deepest pit found to be about 0.12 inches (3.05 nun). Less than 2% of the aluminum cladding was found to be breached resulting in less than 5% of the uranium surface area being affected by corrosion. The overall integrity of the target slug remained intact

  20. Plantar pitted keratolysis: a study from non-risk groups

    Directory of Open Access Journals (Sweden)

    Asli Feride Kaptanoglu

    2012-02-01

    Full Text Available Pitted keratolysis is an acquired, superficial bacterial infection of the skin which is characterized by typical malodor and pits in the hyperkeratotic areas of the soles. It is more common in barefooted people in tropical areas, or those who have to wear occlusive shoes, such as soldiers, sailors and athletes. In this study, we evaluated 41 patients who had been diagnosed with plantar pitted keratolysis. The patients were of high socioeconomic status, were office-workers, and most had a university degree. Malodor and plantar hyperhydrosis were the most frequently reported symptoms. The weight-bearing metatarsal parts of the feet were those most affected. Almost half the women in the study gave a history of regular pedicure and foot care in a spa salon. Mean treatment duration was 19 days. All patients were informed about the etiology of the disease, predisposing factors and preventive methods. Recurrences were observed in only 17% of patients during the one year follow-up period. This study emphasizes that even malodorous feet among non-risk city dwellers may be a sign of plantar pitted keratolysis. A study of the real incidence of the disease in a large population-based series is needed.

  1. Dental Pit and Fissure Sealants: Implications for School Health Personnel.

    Science.gov (United States)

    McCormack-Brown, K. R.; And Others

    1989-01-01

    To promote good personal hygiene practices in students, school health personnel must be informed about dental pit and fissure sealants and related programs. Adoption and maintenance of such programs may depend on the success of school health personnel in educating administrators and policymakers. (SM)

  2. A critical analysis of physiochemical properties influencing pit latrine ...

    African Journals Online (AJOL)

    User

    also done after each day of field sampling. During sampling maximum care was done to avoid spillage and contact of faecal sludge with skin. Furthermore, all waste samples onsite were disposed of according to the standards for faeces sample disposal and where possible pits were dug for purposes of burying the wastes.

  3. Rubber Tire Dozer Operator. Open Pit Mining Job Training Series.

    Science.gov (United States)

    British Columbia Dept. of Education, Victoria.

    This training outline for rubber tire dozer operators, one in a series of eight outlines, is designed primarily for company training foremen or supervisors and for trainers to use as an industry-wide guideline for heavy equipment operator training in open pit mining in British Columbia. Intended as a guide for preparation of lesson plans both for…

  4. New diagnostic technology and hidden pits and fissures caries

    Directory of Open Access Journals (Sweden)

    Fabrizio Guerra

    2015-10-01

    Full Text Available The accuracy in pits and fissures caries detection is of paramount importance in dental caries primary and secondary prevention. A combination of visual examination and probing is currently the mainstay of occlusal caries diagnosis. Unfortunately, these types of inspection alone may leave a certain number of pit and fissure caries undetected. The Vista Cam iX fluorescence camera (Durr Dental, Bietigheim-Bissingen, Germany is a novel dental diagnostic tool for quantitative assessment of dental caries with high specificity for carious lesions detection. In the presented cases photographic images, representing the visual diagnostic approach, are applied as integration to VistaCam iX Proof images. A step-by-step sequence of inspection and assessment of operative treatment need is presented in a case of hidden pit and fissure caries on a permanent molar. Based on the reported case, it could be observed that VistaCam iX Proof shows promising results in hidden pits and fissures caries detection and could be considered a non-invasive examination method that facilitate the detection of early lesions and a potential diagnostic aid.

  5. Atomic force microscopy of torus-bearing pit membranes

    Science.gov (United States)

    Roland R. Dute; Thomas Elder

    2011-01-01

    Atomic force microscopy was used to compare the structures of dried, torus-bearing pit membranes from four woody species, three angiosperms and one gymnosperm. Tori of Osmanthus armatus are bipartite consisting of a pustular zone overlying parallel sets of microfibrils that form a peripheral corona. Microfibrils of the corona form radial spokes as they traverse the...

  6. Optimal grade control sampling practice in open-pit mining

    DEFF Research Database (Denmark)

    Engström, Karin; Esbensen, Kim Harry

    2017-01-01

    Misclassification of ore grades results in lost revenues, and the need for representative sampling procedures in open pit mining is increasingly important in all mining industries. This study evaluated possible improvements in sampling representativity with the use of Reverse Circulation (RC) drill...

  7. Micro Pulsed Inductive Thruster with Solid Fuel Option (uPIT_SF), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The Micro Pulsed Inductive Thruster with Solid Fuel Option (µPIT_SF) is a high-precision impulse bit electromagnetic plasma micro-thruster. The µPIT prototype is a...

  8. Demonstration of In-Situ Stabilization of Buried Waste at Pit G-11 at the Brookhaven National laboratory Glass Pits Disposal Site

    International Nuclear Information System (INIS)

    Dwyer, B.P.; Gilbert, J.; Heiser, J.

    1999-01-01

    In 1989 BNL was added to the EPAs National Priorities List. The site is divided into seven operable units (OU). OU-I includes the former landfill area. The field task site is noted as the AOC 2C Glass Holes location. Beginning in the 1960s and continuing into the 1980s, BNL disposed of laboratory waste (glassware, chemicals and animal carcasses) in numerous shallow pits. The drivers for remediating the pits are; historical records that indicate hazardous materials may have been disposed of in the pits; ground water contamination down gradient of the pits; a test excavation of one of the glass holes that unearthed laboratory glass bottles with unidentified liquids still contained; and the fact that BNL rests atop an EPA designated sole-source aquifer. The specific site chosen for this demonstration was pit G-11. The requirements that lead to choosing this pit were; a well characterized pit and a relatively isolated pit where our construction operations would not impact on adjacent pits. The glass holes area, including pit G-11, was comprehensively surveyed using a suite of geophysical techniques (e.g., EM-31, EM-61, GPR). Prior to stabilizing the waste form a subsurface barrier was constructed to contain the entire waste pit. The pit contents were then stabilized using a cement grout applied via jet grouting. The stabilization was performed to make removal of the waste from the pit easier and safer in terms of worker exposure. The grouting process would mix and masticate the waste and grout and form a single monolithic waste form. This large monolith would then be subdivided into smaller 4 foot by 4 foot by 10-12 foot block using a demolition grout. The smaller blocks would then be easily removed from the site and disposed of in a CERCLA waste site

  9. Evaluation of water chemistry on the pitting susceptibility of aluminum

    International Nuclear Information System (INIS)

    Chandler, G.T.; Sindelar, R.L.; Lam, P.S.

    1997-01-01

    Aluminum-clad spent nuclear fuels are being stored in water in the Receiving Basin for Off-site Fuels (RBOF) and the reactor disassembly (cooling) basins at the Savannah River Site (SRS). Experience shows that fuels stored in water are subject to rapid pitting corrosion if the water quality is poor. Upgrade projects and actions, including those to improve water quality, were recently undertaken to upgrade the disassembly basins for extended storage. A technical strategy was developed for continued basin storage of aluminum-clad fuel assemblies. The strategy includes development and implementation of basin technical standards for water quality to minimize attack due to pitting corrosion over a desired storage period. In the absence of localized corrosion, only slow, general corrosion of the cladding would be expected. A laboratory corrosion program is being performed to provide the bases for technical standards by identifying the region of aggressive water qualities where existing oxide films would tend to break down and pits would initiate and remain active. Initial results from corrosion potential and cyclic polarization testing of aluminum alloys in various water chemistries have shown that low conductivity water (< 50 μS/cm) should not be aggressive to cause self-pitting corrosion. Initial results from tests of 8001 and 5052 aluminum and aluminium-10% uranium alloy indicate that a strong galvanic couple should not exist between the aluminum cladding materials and the aluminum-uranium fuel. Additional laboratory testing will include immersion testing to allow characterization of the growth rate of active pits to benchmark a kinetic model. This model will form the basis for a water quality technical standard and enable prediction of the life of aluminum-clad spent nuclear fuels in basin storage

  10. Standardized emissions inventory methodology for open-pit mining areas.

    Science.gov (United States)

    Huertas, Jose I; Camacho, Dumar A; Huertas, Maria E

    2011-08-01

    There is still interest in a unified methodology to quantify the mass of particulate material emitted into the atmosphere by activities inherent to open-pit mining. For the case of total suspended particles (TSP), the current practice is to estimate such emissions by developing inventories based on the emission factors recommended by the USEPA for this purpose. However, there are disputes over the specific emission factors that must be used for each activity and the applicability of such factors to cases quite different to the ones under which they were obtained. There is also a need for particulate matter with an aerodynamic diameter less than 10 μm (PM(10)) emission inventories and for metrics to evaluate the emission control programs implemented by open-pit mines. To address these needs, work was carried out to establish a standardized TSP and PM(10) emission inventory methodology for open-pit mining areas. The proposed methodology was applied to seven of the eight mining companies operating in the northern part of Colombia, home to the one of the world's largest open-pit coal mining operations (∼70 Mt/year). The results obtained show that transport on unpaved roads is the mining activity that generates most of the emissions and that the total emissions may be reduced up to 72% by spraying water on the unpaved roads. Performance metrics were defined for the emission control programs implemented by mining companies. It was found that coal open-pit mines are emitting 0.726 and 0.180 kg of TSP and PM(10), respectively, per ton of coal produced. It was also found that these mines are using on average 1.148 m(2) of land per ton of coal produced per year.

  11. Evaluation of water chemistry on the pitting susceptibility of aluminum

    Energy Technology Data Exchange (ETDEWEB)

    Chandler, G.T.; Sindelar, R.L.; Lam, P.S. [Westinghouse Savannah River Co., Aiken, SC (United States)

    1997-12-01

    Aluminum-clad spent nuclear fuels are being stored in water in the Receiving Basin for Off-site Fuels (RBOF) and the reactor disassembly (cooling) basins at the Savannah River Site (SRS). Experience shows that fuels stored in water are subject to rapid pitting corrosion if the water quality is poor. Upgrade projects and actions, including those to improve water quality, were recently undertaken to upgrade the disassembly basins for extended storage. A technical strategy was developed for continued basin storage of aluminum-clad fuel assemblies. The strategy includes development and implementation of basin technical standards for water quality to minimize attack due to pitting corrosion over a desired storage period. In the absence of localized corrosion, only slow, general corrosion of the cladding would be expected. A laboratory corrosion program is being performed to provide the bases for technical standards by identifying the region of aggressive water qualities where existing oxide films would tend to break down and pits would initiate and remain active. Initial results from corrosion potential and cyclic polarization testing of aluminum alloys in various water chemistries have shown that low conductivity water (< 50 {micro}S/cm) should not be aggressive to cause self-pitting corrosion. Initial results from tests of 8001 and 5052 aluminum and aluminium-10% uranium alloy indicate that a strong galvanic couple should not exist between the aluminum cladding materials and the aluminum-uranium fuel. Additional laboratory testing will include immersion testing to allow characterization of the growth rate of active pits to benchmark a kinetic model. This model will form the basis for a water quality technical standard and enable prediction of the life of aluminum-clad spent nuclear fuels in basin storage.

  12. Analysis of Proximity-1 Space Link Interleaved Time Synchronization (PITS) Protocol

    Science.gov (United States)

    Woo, Simon S.

    2011-01-01

    To synchronize clocks between spacecraft in proximity, the Proximity-1 Space Link Interleaved Time Synchronization (PITS) Protocol has been proposed. PITS is based on the NTP Interleaved On-Wire Protocol and is capable of being adapted and integrated into CCSDS Proximity-1 Space Link Protocol with minimal modifications. In this work, we will discuss the correctness and liveness of PITS. Further, we analyze and evaluate the performance of time synchronization latency with various channel error rates in different PITS operational modes.

  13. Studies on soil and water characteristics of Burrow pits for possible ...

    African Journals Online (AJOL)

    Studies on soil and water characteristics of Burrow pits for possible conversion into fish ponds in Niger Delta, Nigeria. ... Soil and water parameters were investigated in 34 burrow pits in Egiland, Rivers State, in the Niger Delta region of Nigeria. The pits surface areas and depths ranged from 30,000 to 40,000 m2 and 1.00 to ...

  14. An investigation of the effect of pit latrine additives on VIP latrine ...

    African Journals Online (AJOL)

    2015-07-04

    Jul 4, 2015 ... trials nor field trials provided any evidence that the use of pit additives has any beneficial effect on pit contents. .... diagram showing how measurements were taken using the infrared laser meter (Bakare, 2014). Laser Tape Measure. Pedestal Top. Wall Support to the pit. Cylindrical rings / concrete walls. P1.

  15. 78 FR 33894 - Proposed Information Collection (Open Burn Pit Registry Airborne Hazard Self-Assessment...

    Science.gov (United States)

    2013-06-05

    ... Burn Pit Registry Airborne Hazard Self-Assessment Questionnaire) Activity: Comment Request AGENCY... to ``OMB Control No. 2900-NEW, Open Burn Pit Registry Airborne Hazard Self-Assessment Questionnaire.... Title: Open Burn Pit Registry Airborne Hazard Self-Assessment Questionnaire, VA Form 10-10066. OMB...

  16. 78 FR 54956 - Agency Information Collection (Open Burn Pit Registry Airborne Hazard Self-Assessment...

    Science.gov (United States)

    2013-09-06

    ... Pit Registry Airborne Hazard Self-Assessment Questionnaire) Activities Under OMB Review AGENCY... Burn Pit Registry Airborne Hazard Self-Assessment Questionnaire.'' SUPPLEMENTARY INFORMATION: Title: Open Burn Pit Registry Airborne Hazard Self-Assessment Questionnaire, VA Form 10-10066. Type of Review...

  17. Study of pitting corrosion in line-pipe steel under the influence of remanent magnetization

    Energy Technology Data Exchange (ETDEWEB)

    Espina-Hernandez, J.H.; Caleyo, F.; Hallen, J.M. [Instituto Politecnico Nacional (IPN), Zacatenco (Mexico)

    2009-07-01

    The influence of remanent magnetization on pitting corrosion in line-pipe steels is studied. Pitting corrosion experiments have been carried out on samples of an API 5L grade 52 steel under a magnetization level of the same order of magnitude of the remanent magnetization in the pipeline wall after in-line inspection based on magnetic flux leakage. The samples were magnetized using rings of the same grade as the investigated steel. Immediately after magnetization, the investigated samples were subjected to pitting by immersing them in a solution containing dissolved Cl{sup -} and SO{sup 2-}{sub 4} and ions. The pitting experiments were conducted during a seven days period. The pit depth distribution and the maximum pit depth in each sample were recorded and used to conduct extreme value analyses of the pitting process in magnetized and non-magnetized control samples. The statistical assessment of the pitting corrosion data collected during this study shows that the magnetic field reduces the average depth of the pit population and also the extreme pit depth values that can be predicted from the maximum values observed in the magnetized samples in comparison with to the non-magnetized control samples. Scanning electron microscopy observations show that the magnetic field alters the pit morphology by increasing the pit mouth opening. (author)

  18. The convection stack - a device for ridding pit toilets of bad odor

    Science.gov (United States)

    J. Alan Wagar

    1962-01-01

    One of the common problems on outdoor recreation areas is that pit toilets smell bad. Flush plumbing is one answer to the problem. But pit toilets are needed in many places where modern sewage systems are economically or physically impractical. To reduce the smell of the pit toilet, one simple, safe, and inexpensive device that can be used is the convection stack....

  19. Effect of PIT tags on the survival and recruitment of Great Tits Parus major

    NARCIS (Netherlands)

    Nicolaus, Marion; Bouwman, Karen M.; Dingemanse, Niels J.

    2008-01-01

    We describe the use of subcutaneous passive integrated transponder (PIT) tags in nestling and adult Great Tits Parus major. We investigated whether subcutaneous PIT tags affected fledging success, winter condition, survival and/or recruitment. We found no negative effects of PIT tags on any of these

  20. Syngeneic Mouse Models of Oral Cancer Are Effectively Targeted by Anti-CD44-Based NIR-PIT.

    Science.gov (United States)

    Nagaya, Tadanobu; Nakamura, Yuko; Okuyama, Shuhei; Ogata, Fusa; Maruoka, Yasuhiro; Choyke, Peter L; Allen, Clint; Kobayashi, Hisataka

    2017-12-01

    Oral cavity squamous cell carcinoma (OSCC) is considered one of the most aggressive subtypes of cancer. Anti-CD44 monoclonal antibodies (mAb) are a potential therapy against CD44 expressing OSCC; however, to date the therapeutic effects have been disappointing. Here, a new cancer treatment is described, near-infrared photoimmunotherapy (NIR-PIT), that uses anti-CD44 mAbs conjugated to the photoabsorber IR700DX. This conjugate is injected into mice harboring one of three CD44 expressing syngeneic murine oral cancer cell (MOC) lines, MOC1 (immunogenic), MOC2 mKate2 (moderately immunogenic), and MOC2-luc (poorly immunogenic). Binding of the anti-CD44-IR700 conjugate was shown to be specific and cell-specific cytotoxicity was observed after exposure of the cells to NIR light in vitro The anti-CD44-IR700 conjugate, when assessed in vivo , demonstrated deposition within the tumor with a high tumor-to-background ratio. Tumor-bearing mice were separated into four cohorts: no treatment; 100 μg of anti-CD44-IR700 i.v. only; NIR light exposure only; and 100 μg of anti-CD44-IR700 i.v. with NIR light exposure. NIR-PIT therapy, compared with the other groups, significantly inhibited tumor growth and prolonged survival in all three cell model systems. In conclusion, these data reveal that anti-CD44 antibodies are suitable as mAb-photoabsorber conjugates for NIR-PIT in MOC cells. Implications: This study using syngeneic mouse models, which better model the disease in humans than conventional xenografts, suggests that NIR-PIT with anti-CD44-IR700 is a potential candidate for the treatment of OSCC. Mol Cancer Res; 15(12); 1667-77. ©2017 AACR . ©2017 American Association for Cancer Research.

  1. Impacts of swine manure pits on groundwater quality

    International Nuclear Information System (INIS)

    Krapac, I.G.; Dey, W.S.; Roy, W.R.; Smyth, C.A.; Storment, E.; Sargent, S.L.; Steele, J.D.

    2002-01-01

    New information is presented on impacts on groundwater by manure storage in deep ground pits. - Manure deep-pits are commonly used to store manure at confined animal feeding operations. However, previous to this study little information had been collected on the impacts of deep-pits on groundwater quality to provide science-based guidance in formulating regulations and waste management strategies that address risks to human health and the environment. Groundwater quality has been monitored since January 1999 at two hog finishing facilities in Illinois that use deep-pit systems for manure storage. Groundwater samples were collected on a monthly basis and analyzed for inorganic and bacteriological constituent concentrations. The two sites are located in areas with geologic environments representing different vulnerabilities for local groundwater contamination. One site is underlain by more than 6 m of clayey silt, and 7-36 m of shale. Concentrations of chloride, ammonium, phosphate, and potassium indicated that local groundwater quality had not been significantly impacted by pit leakage from this facility. Nitrate concentrations were elevated near the pit, often exceeding the 10 mg N/l drinking water standard. Isotopic nitrate signatures suggested that the nitrate was likely derived from soil organic matter and fertilizer applied to adjacent crop fields. At the other site, sandstone is located 4.6-6.1 m below land surface. Chloride concentrations and δ 15 N and δ 18 O values of dissolved nitrate indicated that this facility may have limited and localized impacts on groundwater. Other constituents, including ammonia, potassium, phosphate, and sodium were generally at or less than background concentrations. Trace- and heavy-metal concentrations in groundwater samples collected from both facilities were at concentrations less than drinking water standards. The concentration of inorganic constituents in the groundwater would not likely impact human health. Fecal

  2. New insight into the pit-to-crack transition from finite element analysis of the stress and strain distribution around a corrosion pit

    International Nuclear Information System (INIS)

    Turnbull, A.; Wright, L.; Crocker, L.

    2010-01-01

    A finite element (FE) analysis has been undertaken to evaluate the stress and strain distribution associated with a single corrosion pit in a cylindrical steel specimen stressed remotely in tension. A key observation was the localisation of plastic strain to the pit walls (just below the surface of the specimen). Simulation of a growing pit in a static stress field indicated corresponding plastic strain rates that were commensurate with values associated with stress corrosion cracking. This observation introduces a wholly new concept in understanding of the evolution of stress corrosion cracks from pits and correlates with recent X-ray tomography measurements.

  3. Formation of primary pit connection during conchocelis phase of Porphyra yezoensis (Bangiophyceae, Rhodophyta)

    Science.gov (United States)

    Shual, Li; Jiang, Ming; Duan, Delin

    2006-09-01

    The formation of pit connection during conchocelis phase of Porphyra yezoensis Ueda was observed and examined with transmission electron microscope (TEM) and epifluorence microscope. It is indicated that the pit connection was formed in late stage of conchocelis phase and the early stages of conchosporangial cell development, and disappeared in bispore stage. The pit connection contained a thin membrane layer at outer pit plug. Stained with 4', 6'-diamidino-2-phenylidole dihydrochloride hydrate (DAPI), transferring of DNA or RNA between adjacent cells were observed in late stage of conchocelis development, it was deduced that pit connection might serve as a channel for signal transduction and genetic substance transportation in conchocelis phase.

  4. Water and chemical budgets of gravel pit lakes : Case studies of fluvial gravel pit lakes along the Meuse River (The Netherlands) and coastal gravel pit lakes along the Adriatic Sea (Ravenna, Italy)

    NARCIS (Netherlands)

    Mollema, P.N.

    2016-01-01

    Gravel pit lakes form when gravel is excavated from below the water table of a phreatic or shallow confined aquifer. Typically many of these lakes are concentrated along naturally occurring sedimentary gravel deposits in areas where gravel is needed for construction. Most gravel pit lakes are

  5. Acute toxicity, histopathology, and coagulopathy in American kestrels (Falco sparverius) following administration of the rodenticie diphacinone

    Science.gov (United States)

    Rattner, Barnett A.; Horak, Katherine E.; Warner, Sarah E.; Day, Daniel D.; Meteyer, Carol U.; Voler, Steven F.; Eisemann, John D.; Johnston, John J.

    2011-01-01

    The acute oral toxicity of the anticoagulant rodenticide diphacinone was found to be over 20 times greater in American kestrels (Falco sparverius; median lethal dose 96.8 mg/kg body weight) compared with Northern bobwhite (Colinus virginianus) and mallards (Anas platyrhynchos). Modest evidence of internal bleeding was observed at necropsy, although histological examination of heart, liver, kidney, lung, intestine, and skeletal muscle revealed hemorrhage over a wide range of doses (35.1-675 mg/kg). Residue analysis suggests that the half-life of diphacinone in the liver of kestrels that survived was relatively short, with the majority of the dose cleared within 7 d of exposure. Several precise and sensitive clotting assays (prothrombin time, Russell's viper venom time, thrombin clotting time) were adapted for use in this species, and oral administration of diphacinone at 50 mg/kg increased prothrombin time and Russell?s viper venom time at 48 and 96 h postdose compared with controls. Prolongation of in vitro clotting time reflects impaired coagulation complex activity, and generally corresponded with the onset of overt signs of toxicity and lethality. In view of the toxicity and risk evaluation data derived from American kestrels, the involvement of diphacinone in some raptor mortality events, and the paucity of threshold effects data following short-term dietary exposure for birds of prey, additional feeding trials with captive raptors are warranted to characterize more fully the risk of secondary poisoning.

  6. The influence of tungsten on the pitting of aluminum films

    International Nuclear Information System (INIS)

    Shaw, B.A.; Fritz, T.L.; Davis, G.D.; Moshier, W.C.

    1990-01-01

    Many of the alloying additions responsible for the corrosion resistance of stainless steels can also be used to enhance the passivity of aluminum, provided that these elements remain in solid solution in the alloy. Passivity enhancing elements such as Cr, Mo, Ta, Zr, and W typically exhibit very low solubility limits in aluminum, below 1 atomic percent, and at these concentrations exert little influence on corrosion behavior. However, these solubility limits can be increased with a concomitant enhancement in corrosion performance if the alloys are produced using a rapid solidification process. One such process is co-sputter deposition of two metals, such as Al and W, simultaneously to form a binary alloy of W in solid solution with Al. Co-sputter deposition is routinely used to produce compound semiconductor films. The authors report on shifts in pitting potentials and on the effect of a transition element (W) on pitting resistance of Al

  7. Integrating Safeguards into the Pit Disassembly and Conversion Facility

    International Nuclear Information System (INIS)

    Clark, T.G.

    2002-01-01

    In September 2000, the United States and the Russian Federation entered into an agreement which stipulates each country will irreversibly transform 34 metric tons of weapons-grade plutonium into material which could not be used for weapon purposes. Supporting the Department of Energy's (DOE) program to dispose of excess nuclear materials, the Pit Disassembly and Conversion Facility (PDCF) is being designed and constructed to disassemble the weapon ''pits'' and convert the nuclear material to an oxide form for fabrication into reactor fuel at the separate Mixed Oxide Fuel Fabrication Facility. The PDCF design incorporates automation to the maximum extent possible to facilitate material safeguards, reduce worker dose, and improve processing efficiency. This includes provisions for automated guided vehicle movements for shipping containers, material transport via automated conveyor between processes, remote process control monitoring, and automated Nondestructive Assay product systems

  8. Geologic report for the Weldon Spring Raffinate Pits Site

    International Nuclear Information System (INIS)

    1984-10-01

    A preliminary geologic site characterization study was conducted at the Weldon Spring Raffinate Pits Site, which is part of the Weldon Spring Site, in St. Charles County, Missouri. The Raffinate Pits Site is under the custody of the Department of Energy (DOE). Surrounding properties, including the Weldon Spring chemical plant, are under the control of the Department of the Army. The study determined the following parameters: site stratigraphy, lithology and general conditions of each stratigraphic unit, and groundwater characteristics and their relation to the geology. These parameters were used to evaluate the potential of the site to adequately store low-level radioactive wastes. The site investigation included trenching, geophysical surveying, borehole drilling and sampling, and installing observation wells and piezometers to monitor groundwater and pore pressures

  9. Surface aspects of pitting and stress corrosion cracking

    Science.gov (United States)

    Truhan, J. S., Jr.; Hehemann, R. F.

    1977-01-01

    The pitting and stress corrosion cracking of a stable austenitic stainless steel in aqueous chloride environments were investigated using a secondary ion mass spectrometer as the primary experimental technique. The surface concentration of hydrogen, oxygen, the hydroxide, and chloride ion, magnesium or sodium, chromium and nickel were measured as a function of potential in both aqueous sodium chloride and magnesium chloride environments at room temperature and boiling temperatures. It was found that, under anodic conditions, a sharp increase in the chloride concentration was observed to occur for all environmental conditions. The increase may be associated with the formation of an iron chloride complex. Higher localized chloride concentrations at pits and cracks were also detected with an electron microprobe.

  10. Development of pits and cones on ion bombarded copper

    International Nuclear Information System (INIS)

    Tanovic, L.A.; Carter, G.; Nobes, M.J.; Whitton, I.L.; Williams, J.S.

    1980-01-01

    The formation of pits and cones on Ar ion bombarded copper has been studied. Carefully polished surfaces of large grained 99.999% pure copper crystals have been bombarded at normal incidence with 40 keV argon ions. The cone formation has been investigated for annealed and non-annealed crystals at room temperature and at 30 K and in the case of monocrystal and polycrystal samples. Although in the most other studies the presence of impurities is as a necessary condition for generation of cones and pits the obtained experimental results show that under certain conditions these features are formed on clean surfaces. It is shown that the dominant parameter in the production of cones on copper is the crystal orientation [ru

  11. A Bayesian approach to modeling and predicting pitting flaws in steam generator tubes

    International Nuclear Information System (INIS)

    Yuan, X.-X.; Mao, D.; Pandey, M.D.

    2009-01-01

    Steam generators in nuclear power plants have experienced varying degrees of under-deposit pitting corrosion. A probabilistic model to accurately predict pitting damage is necessary for effective life-cycle management of steam generators. This paper presents an advanced probabilistic model of pitting corrosion characterizing the inherent randomness of the pitting process and measurement uncertainties of the in-service inspection (ISI) data obtained from eddy current (EC) inspections. A Markov chain Monte Carlo simulation-based Bayesian method, enhanced by a data augmentation technique, is developed for estimating the model parameters. The proposed model is able to predict the actual pit number, the actual pit depth as well as the maximum pit depth, which is the main interest of the pitting corrosion model. The study also reveals the significance of inspection uncertainties in the modeling of pitting flaws using the ISI data: Without considering the probability-of-detection issues and measurement errors, the leakage risk resulted from the pitting corrosion would be under-estimated, despite the fact that the actual pit depth would usually be over-estimated.

  12. Heterogeneous distribution of pectin epitopes and calcium in different pit types of four angiosperm species.

    Science.gov (United States)

    Plavcová, Lenka; Hacke, Uwe G

    2011-12-01

    Intervessel pits act as safety valves that prevent the spread of xylem embolism. Pectin-calcium crosslinks within the pit membrane have been proposed to affect xylem vulnerability to cavitation. However, as the chemical composition of pit membranes is poorly understood, this hypothesis has not been verified. Using electron microscopy, immunolabeling, an antimonate precipitation technique, and ruthenium red staining, we studied the distribution of selected polysaccharides and calcium in the pit membranes of four angiosperm tree species. We tested whether shifts in xylem vulnerability resulting from perfusion of stems with a calcium chelating agent corresponded with the distribution of pectic homogalacturonans (HG) and/or calcium within interconduit pit membranes. No HG were detected in the main part of intervessel pit membranes, but were consistently found in the marginal membrane region known as the annulus. Calcium colocalized with HG in the annulus. In contrast to intervessel pits, the membrane of vessel-ray pits showed a high pectin content. The presence of two distinct chemical domains, the annulus and the actual pit membrane, can have substantial implications for pit membrane functioning. We propose that the annulus could affect the observed shift in xylem vulnerability after calcium removal by allowing increased pit membrane deflection. © 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.

  13. Quantitative Correlation of 7B04 Aluminum Alloys Pitting Corrosion Morphology Characteristics with Stress Concentration Factor

    Science.gov (United States)

    Liu, Zhiguo; Yan, Guangyao; Mu, Zhitao; Li, Xudong

    2018-01-01

    The accelerated pitting corrosion test of 7B04 aluminum alloy specimen was carried out according to the spectrum which simulated airport environment, and the corresponding pitting corrosion damage was obtained and was defined through three parameters A and B and C which respectively denoted the corrosion pit surface length and width and corrosion pit depth. The ratio between three parameters could determine the morphology characteristics of corrosion pits. On this basis the stress concentration factor of typical corrosion pit morphology under certain load conditions was quantitatively analyzed. The research shows that the corrosion pits gradually incline to be ellipse in surface and moderate in depth, and most value of B/A and C/A lies in 1 between 4 and few maximum exceeds 4; The stress concentration factor Kf of corrosion pits is obviously affected by the its morphology, the value of Kf increases with corrosion pits depth increasement under certain corrosion pits surface geometry. Also, the value of Kf decreases with surface width increasement under certain corrosion pits depth. The research conclusion can set theory basis for corrosion fatigue life analysis of aircraft aluminum alloy structure.

  14. The Effects of Hot Corrosion Pits on the Fatigue Resistance of a Disk Superalloy

    Science.gov (United States)

    Gabb, Timothy P.; Telesman, Jack; Hazel, Brian; Mourer, David P.

    2009-01-01

    The effects of hot corrosion pits on low cycle fatigue life and failure modes of the disk superalloy ME3 were investigated. Low cycle fatigue specimens were subjected to hot corrosion exposures producing pits, then tested at low and high temperatures. Fatigue lives and failure initiation points were compared to those of specimens without corrosion pits. Several tests were interrupted to estimate the fraction of fatigue life that fatigue cracks initiated at pits. Corrosion pits significantly reduced fatigue life by 60 to 98 percent. Fatigue cracks initiated at a very small fraction of life for high temperature tests, but initiated at higher fractions in tests at low temperature. Critical pit sizes required to promote fatigue cracking were estimated, based on measurements of pits initiating cracks on fracture surfaces.

  15. Dependence of Crystallographic Orientation on Pitting Corrosion Behavior of Ni-Fe-Cr Alloy 028

    Science.gov (United States)

    Zhang, LiNa; Szpunar, Jerzy A.; Dong, JianXin; Ojo, Olanrewaju A.; Wang, Xu

    2018-03-01

    The influence of crystallographic orientation on the pitting corrosion behavior of Ni-Fe-Cr alloy 028 was studied using a combination of X-ray diffraction (XRD), electron backscatter diffraction (EBSD), potentiodynamic polarization technique, and atomic force microscopy (AFM). The results show that there is anisotropy of pitting corrosion that strongly depends on crystallographic orientation of the surface plane. The distribution of pit density in a standard stereographic triangle indicates that the crystallographic planes close to {100} are more prone to pitting corrosion compared to planes {110} and {111}. The surface energy calculation of (001) and (111) shows that the plane with a high atomic packing density has a low surface energy with concomitant strong resistance to pitting corrosion. A correlation function between crystallographic orientation and pitting corrosion susceptibility suggests a method that not only predicts the pitting resistance of known textured materials, but also could help to improve corrosion resistance by controlling material texture.

  16. Markov chain model helps predict pitting corrosion depth and rate in underground pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Caleyo, F.; Velazquez, J.C.; Hallen, J. M. [ESIQIE, Instituto Politecnico Nacional, Mexico D. F. (Mexico); Esquivel-Amezcua, A. [PEMEX PEP Region Sur, Villahermosa, Tabasco (Mexico); Valor, A. [Universidad de la Habana, Vedado, La Habana (Cuba)

    2010-07-01

    Recent reports place pipeline corrosion costs in North America at seven billion dollars per year. Pitting corrosion causes the higher percentage of failures among other corrosion mechanisms. This has motivated multiple modelling studies to be focused on corrosion pitting of underground pipelines. In this study, a continuous-time, non-homogenous pure birth Markov chain serves to model external pitting corrosion in buried pipelines. The analytical solution of Kolmogorov's forward equations for this type of Markov process gives the transition probability function in a discrete space of pit depths. The transition probability function can be completely identified by making a correlation between the stochastic pit depth mean and the deterministic mean obtained experimentally. The model proposed in this study can be applied to pitting corrosion data from repeated in-line pipeline inspections. Case studies presented in this work show how pipeline inspection and maintenance planning can be improved by using the proposed Markovian model for pitting corrosion.

  17. SIMULATION OF OLIVE PITS PYROLYSIS IN A ROTARY KILN PLANT

    OpenAIRE

    Giacobbe Braccio; Vincenzo Lorefice; Cesare Freda; Enzo Benanti; Vinod Kumar Sharma

    2011-01-01

    This work deals with the simulation of an olive pits fed rotary kiln pyrolysis plant installed in Southern Italy. The pyrolysis process was simulated by commercial software CHEMCAD. The main component of the plant, the pyrolyzer, was modelled by a Plug Flow Reactor in accordance to the kinetic laws. Products distribution and the temperature profile was calculated along reactor's axis. Simulation results have been found to fit well the experimental data of pyrolysis. Moreover, sensitivity anal...

  18. Analysis of traversable pits model to make intelligent wheeled vehicles

    Directory of Open Access Journals (Sweden)

    F. Abbasi

    2017-11-01

    Full Text Available In this paper, the issue of passing wheeled vehicles from pits is discussed. The issue is modeled by defining the limits of passing wheeled vehicles. The proposed model has been studied based on changes in the effective parameters. Finally, in order to describe the problem, the proposed model has been solved for wheeled vehicles based on the effective parameters by using one of the numerical methods.

  19. Image features of herniation pit of the femoral neck

    International Nuclear Information System (INIS)

    Zhang Xuezhe; Li Guangming; Wang Cunli; Wang Guimin

    2008-01-01

    Objective: To evaluate imaging appearances of herniation pit of the femoral neck. Methods: We retrospectively analyzed the X-ray, CT and MRI findings of 9 patients with herniation pit of the femoral neck. All nine patients were male with the age ranging from 21 to 73 years. They had pain in the hip from two months to two years duration. Results: The bilateral hips were affected in six patients, the right hips in the other 3 patients. Of the nine patients, X-ray plain films (2 cases), CT scanning(6 cases), and MR scanning (5 cases ) were performed. The size of the lesions ranged from 0.5 cm x 0.6 cm to 1.0 cm x 1.5 cm, located in the anterosuperior portion of the femoral neck (n=7) or anteroinferior portion (n=2). X-ray plain films showed an osteolytic lesion surrounded by a sclerotic rim. CT scanning showed the lesion just below the cortex of the femoral neck surrounded by a rim of sclerosis or associated with a small cortical break in two patients. MR scanning showed low signal intensity in five patients on T 1 WI and high signal intensity surrounded by a rim of low signal intensity (n=3) or low signal intensity (n=2) on T 2 WI, and high signal intensity on fat suppression MR image. A small joint effusion was observed in two cases on T 2 WI. Conclusion: The CT and MRI findings of herniation pit of the femoral neck are characteristic, it is useful in defining the diagnosis of the herniation pit of the femoral neck. (authors)

  20. A mathematical model of crevice and pitting corrosion. Pt. 2

    International Nuclear Information System (INIS)

    Sharland, S.M.

    1985-09-01

    The time-independent equations of mass transport governing the concentration of species and electrode potential within a corroding crevice or pit are solved using a number of mathematical approximations based on physical observations. A variety of analytic and numerical techniques is described and several methods which reduce computing time are developed. A simple method of time stepping is described for a calculation of the effect of precipitation of solid hydroxide in the crevice. (author)

  1. 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.

  2. Viper Plague Project

    Science.gov (United States)

    2009-07-01

    and Streptococcus pyogenes , (gram positive), labeled with the conjugated Proteus antibody, 40x………………………………………………………………………………………….….…….……18 Figure...aureus and Streptococcus pyogenes ) bacterial organisms. After demonstrating its usefulness, the conjugated Proteus antibody has been utilized in a wide...Figure 10i, 10j. Staphylococcus aureus and Streptococcus pyogenes , (gram positive), labeled with the conjugated Proteus antibody, 40x

  3. Visual PEF Reader - VIPER

    Science.gov (United States)

    Luo, Victor; Khanampornpan, Teerapat; Boehmer, Rudy A.; Kim, Rachel Y.

    2011-01-01

    This software graphically displays all pertinent information from a Predicted Events File (PEF) using the Java Swing framework, which allows for multi-platform support. The PEF is hard to weed through when looking for specific information and it is a desire for the MRO (Mars Reconn aissance Orbiter) Mission Planning & Sequencing Team (MPST) to have a different way to visualize the data. This tool will provide the team with a visual way of reviewing and error-checking the sequence product. The front end of the tool contains much of the aesthetically appealing material for viewing. The time stamp is displayed in the top left corner, and highlighted details are displayed in the bottom left corner. The time bar stretches along the top of the window, and the rest of the space is allotted for blocks and step functions. A preferences window is used to control the layout of the sections along with the ability to choose color and size of the blocks. Double-clicking on a block will show information contained within the block. Zooming into a certain level will graphically display that information as an overlay on the block itself. Other functions include using hotkeys to navigate, an option to jump to a specific time, enabling a vertical line, and double-clicking to zoom in/out. The back end involves a configuration file that allows a more experienced user to pre-define the structure of a block, a single event, or a step function. The individual will have to determine what information is important within each block and what actually defines the beginning and end of a block. This gives the user much more flexibility in terms of what the tool is searching for. In addition to the configurability, all the settings in the preferences window are saved in the configuration file as well

  4. Crimson Viper 2015

    Science.gov (United States)

    2015-08-01

    91 Figure 56: Cisco Access Points (Left) ASTERIA (Center) ASUS ROG G751 (Right) ........ 92 Figure 57: Actual gear onsite at CV15 (1) SEEK...Pro Tablet; (5) ASUS server and Toughbook server remote screen...operations. Biometrics Support Technologies Figure 56: Cisco Access Points (Left) ASTERIA (Center) ASUS ROG G751 (Right) The Cisco

  5. Micro pit formation by mercury-sphere collision

    International Nuclear Information System (INIS)

    Ishikura, Syuichi; Kogawa, Hiroyuki; Futakawa, Masatoshi; Kaminaga, Masanori; Hino, Ryutaro

    2004-01-01

    The development of a MW-class spallation neutron source facility is being carried out under the Japan Proton Accelerator Research Complex (J-PARC) Project promoted by JAERI and KEK. A mercury target working as the spallation neutron source will be subjected to pressure waves generated by rapid thermal expansion of mercury due to a pulsed proton beam injection. The pressure wave will impose dynamic stress on the vessel and deform the vessel, which would cause cavitation in mercury. To evaluate the effect of mercury micro jets, driven by cavitation bubble collapse, on the micro-pit formation, analyses on mercury sphere collision were carried out: single bubble dynamics and collision behavior on interface between liquid and solid, which take the nonlinearity due to shock wave in mercury and the strain rate dependency of yield stress in solid metal into account. Analytical results give a good explanation to understand relationship between the micro-pit formation and material properties: the pit size could decrease with increasing the yield strength of materials. (author)

  6. Restoration of Secondary Containment in Double Shell Tank (DST) Pits

    International Nuclear Information System (INIS)

    SHEN, E.J.

    2000-01-01

    Cracks found in many of the double-shell tank (DST) pump and valve pits bring into question the ability of the pits to provide secondary containment and remain in compliance with State and Federal regulations. This study was commissioned to identify viable options for maintain/restoring secondary containment capability in these pits. The basis for this study is the decision analysis process which identifies the requirements to be met and the desired goals (decision criteria) that each option will be weighed against. A facilitated workshop was convened with individuals knowledgeable of Tank Farms Operations, engineering practices, and safety/environmental requirements. The outcome of this workshop was the validation or identification of the critical requirements, definition of the current problem, identification and weighting of the desired goals, baselining of the current repair methods, and identification of potential alternate solutions. The workshop was followed up with further investigations into the potential solutions that were identified in the workshop and through other efforts. These solutions are identified in the body of this report. Each of the potential solutions were screened against the list of requirements and only those meeting the requirements were considered viable options. To expand the field of viable options, hybrid concepts that combine the strongest features of different individual approaches were also examined. Several were identified. The decision analysis process then ranked each of the viable options against the weighted decision criteria, which resulted in a recommended solution. The recommended approach is based upon installing a sprayed on coating system

  7. Restoration of Secondary Containment in Double Shell Tank (DST) Pits

    Energy Technology Data Exchange (ETDEWEB)

    SHEN, E.J.

    2000-10-05

    Cracks found in many of the double-shell tank (DST) pump and valve pits bring into question the ability of the pits to provide secondary containment and remain in compliance with State and Federal regulations. This study was commissioned to identify viable options for maintain/restoring secondary containment capability in these pits. The basis for this study is the decision analysis process which identifies the requirements to be met and the desired goals (decision criteria) that each option will be weighed against. A facilitated workshop was convened with individuals knowledgeable of Tank Farms Operations, engineering practices, and safety/environmental requirements. The outcome of this workshop was the validation or identification of the critical requirements, definition of the current problem, identification and weighting of the desired goals, baselining of the current repair methods, and identification of potential alternate solutions. The workshop was followed up with further investigations into the potential solutions that were identified in the workshop and through other efforts. These solutions are identified in the body of this report. Each of the potential solutions were screened against the list of requirements and only those meeting the requirements were considered viable options. To expand the field of viable options, hybrid concepts that combine the strongest features of different individual approaches were also examined. Several were identified. The decision analysis process then ranked each of the viable options against the weighted decision criteria, which resulted in a recommended solution. The recommended approach is based upon installing a sprayed on coating system.

  8. Investigation of the pitting corrosion of low carbon steel containers

    International Nuclear Information System (INIS)

    Mughabghab, S.F.; Sullivan, T.M.

    1988-01-01

    The present study was undertaken because the prediction of the degradation rate of low carbon steel contains over long time frames is one of the crucial elements in the development of a source term model for low-level shallow land burial. The principal data base considered is that of the NBS corrosion measurements of ferrous materials buried in the ground for periods of up to 18 years. In this investigation, the maximum penetration in mils, hm, due to pitting corrosion was found to conform closely to the relation h m = kt n where it is the exposure time of the sample in years, κ is the pitting parameter in mil/(years) n , and n > O is a parameter related to the aeration property of the soil. The central objective of the present investigation is the determination of the dependence of the pitting parameters κ and n on the soil properties. The result of a detailed linear correlation analysis of κ on one hand, the pH value and the resistivity of the soil on the other hand revealed that κ is principally influenced by the pH value of the soil. The resistivity of the soil is found to play a minor role

  9. Investigation on Floating Lid Construction, pit Water Storage, Ottrupgaard, Denmark

    DEFF Research Database (Denmark)

    Heller, Alfred

    At Ottrupgaard a pit water storage of 1,500 m3 and a lid area of about 700 m2 is built for seasonal storage of a solar collector field of 560 m2. The lid price is the largest component of a pit water store with a cost share of about 57%, more precisely 1,163 Dkr./m2. Due to the large share in price...... the development of lid constructions is crucial for the development of pit water storage and seasonal storage, as it seems that the development of solar collectors will not have a breakthrough in the near future.The Ottrupgaard lid design is basically a sandwich element construction of PUR-foam between two...... conditions floating on hot water. The test lids were examined for tightness by a number of means. The results showed critical construction errors of the first lid design. A redesigned lid showed acceptable results, but also some water penetration into the lid insulation. The entered water gathers...

  10. Open pit coal exploitation viability. Margarita mine. Case of study

    International Nuclear Information System (INIS)

    Veloza, Julia; Molina, Jorge; Mejia, Humberto

    2006-01-01

    This paper provides an analysis of financial viability, planning and design for the new coal open pit exploitation for La Margarita mine, with coal-resources estimated on 440.139,7 ton. Dimension, design and economic evaluation were possible by three exploitation methods: (multiple bench, open cast contour, and terraces). Net present values (NVP) were calculated: $c 817,5; $c 518,5 and $c 645,2 respectively for each method (given in million current Colombian pesos $. $c 2380 are equivalent to $us 1) and rate of return (ROR) 78,33%; 34,0% and 38,62% respectively for each method. These indicators served as a parameter to choose the multiple bench method, which should be recalculated because it was necessary to work jointly with two pits and making feasible the project. in addition a general environmental evaluation was done, which is vital for the exploitation. Important impacts on the flower, animals, air, water were found, and measures of control, prevention and mitigation were stated. it is expected that this paper can be useful as a technical-economical support for the development of the open pit exploitation in the margarita mine

  11. Composição mineral e severidade de "bitter pit" em maçãs 'Catarina' Mineral composition and bitter pit severity in 'Catarina' apples

    Directory of Open Access Journals (Sweden)

    Cassandro Vidal Talamini do Amarante

    2006-04-01

    Full Text Available Maçãs 'Catarina', colhidas na maturação comercial em pomar no município de São Joaquim-SC, foram separadas em quatro lotes de 14 frutos, de acordo com a severidade de incidência de "bitter pit": nula (nenhuma lesão/fruto, baixa (1-2 lesões/fruto, moderada (3-5 lesões/fruto e alta (6-18 lesões/fruto. Foram determinadas as concentrações de Ca, Mg, K e N na casca e na polpa de cada fruto. Foram verificadas relação linear (P 'Catarina' apples were harvested at the commercial maturity in an orchard in São Joaquim-SC and segregated in four lots of 14 fruits with different levels of bitter pit severity: null (none pit/fruit, low (1-2 pits/fruit, moderate (3-5 pits/fruit, and high (6-18 pits/fruit. Nutritional analysis (Ca, Mg, K, and N in the skin and flesh tissues were performed on individual fruits of each severity level. The average number of pits/fruit (calculated for each lot of bitter pit severity showed a negative linear relationship (P < 0.05 with the skin Ca content, and a negative linear relationship (P < 0.05 with the ratios of Mg/Ca, (K+Mg/Ca, and (K+Mg+N/Ca in the skin. For the flesh, the increasing of bitter pit severity was accompanied by significant reduction of Ca and Mg contents. The multivariate analysis (canonical discriminant analysis showed that the Mg/Ca ratio in the skin provided the best discrimination between the lots of fruit with different levels of bitter pit severity. Therefore, for 'Catarina' apples, increasing values of the Mg/Ca ratio in the skin are indicative of fruits with increasing bitter pit susceptibility.

  12. Impacts of swine manure pits on groundwater quality

    Science.gov (United States)

    Krapac, I.G.; Dey, W.S.; Roy, W.R.; Smyth, C.A.; Storment, E.; Sargent, S.L.; Steele, J.D.

    2002-01-01

    Manure deep-pits are commonly used to store manure at confined animal feeding operations. However, previous to this study little information had been collected on the impacts of deep-pits on groundwater quality to provide science-based guidance in formulating regulations and waste management strategies that address risks to human health and the environment. Groundwater quality has been monitored since January 1999 at two hog finishing facilities in Illinois that use deep-pit systems for manure storage. Groundwater samples were collected on a monthly basis and analyzed for inorganic and bacteriological constituent concentrations. The two sites are located in areas with geologic environments representing different vulnerabilities for local groundwater contamination. One site is underlain by more than 6 m of clayey silt, and 7-36 m of shale. Concentrations of chloride, ammonium, phosphate, and potassium indicated that local groundwater quality had not been significantly impacted by pit leakage from this facility. Nitrate concentrations were elevated near the pit, often exceeding the 10 mg N/l drinking water standard. Isotopic nitrate signatures suggested that the nitrate was likely derived from soil organic matter and fertilizer applied to adjacent crop fields. At the other site, sandstone is located 4.6-6.1 m below land surface. Chloride concentrations and ??15N and ??18O values of dissolved nitrate indicated that this facility may have limited and localized impacts on groundwater. Other constituents, including ammonia, potassium, phosphate, and sodium were generally at or less than background concentrations. Trace- and heavy-metal concentrations in groundwater samples collected from both facilities were at concentrations less than drinking water standards. The concentration of inorganic constituents in the groundwater would not likely impact human health. Fecal streptococcus bacteria were detected at least once in groundwater from all monitoring wells at both sites

  13. Fokker-Planck modeling of pitting corrosion in underground pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Camacho, Eliana Nogueira [Risco Ambiental Engenharia, Rio de Janeiro, RJ (Brazil); Melo, Paulo F. Frutuoso e [Coordenacao dos Programas de Pos-Graduacao de Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear; Saldanha, Pedro Luiz C. [Comissao Nacional de Energia Nuclear (CGRC/CNEN), Rio de Janeiro, RJ (Brazil). Coordenacao Geral de Reatores e Ciclo do Combustivel; Silva, Edson de Pinho da [Universidade Federal Rural do Rio de Janeiro (UFRRJ), Seropedica, RJ (Brazil). Dept. of Physics

    2011-07-01

    Full text: The stochastic nature of pitting corrosion has been recognized since the 1930s. It has been learned that this damage retains no memory of its past. Instead, the future state is determined only by the knowledge of its present state. This Markovian property that underlies the stochastic process governing pitting corrosion has been explored as a discrete Markovian process by many authors since the beginning of the 1990s for underground pipelines of the oil and gas industries and nuclear power plants. Corrosion is a genuine continuous time and space state Markovian process, so to model it as a discrete time and/or state space is an approximation to the problem. Markovian chains approaches, with an increasing number of states, could involve a large number of parameters, the transition rates between states, to be experimentally determined. Besides, such an increase in the number of states produces matrices with huge dimensions leading to time-consuming computational solutions. Recent approaches involving Markovian discrete process have overcome those difficulties but, on the other hand, a large number of soil and pipe stochastic variables have to be known. In this work we propose a continuous time and space state approach to the evolution of pit corrosion depths in underground pipelines. In order to illustrate the application of the model for defect depth growth a combination of real life data and Monte Carlo simulation was used. The process is described by a Fokker-Planck equation. The Fokker-Planck equation is completely determined by the knowledge of two functions known as the drift and diffusion coefficients. In this work we also show that those functions can be estimated from corrosion depth data from in-line inspections. Some particular forms of drift and diffusion coefficients lead to particular Fokker-Planck equations for which analytical solutions are known, as is the case for the Wiener process, the Ornstein-Uhlenbeck process and the Brownian motion

  14. Canister Storage Building Receiving Pit Modification Informal Design Verification

    International Nuclear Information System (INIS)

    KRIEG, S.A.

    2000-01-01

    The design for modifications to the CSB Cask Receiving pit guides was verified by the informal design verification (meeting) method on August 9, 2000. The invited list of attendees and the meeting attendance sheet are included in attachment 1. The design modifications that were reviewed are documented in ECN 654484 (attachment 2). The requirement that the design is to be verified against is to ''center the transportation cask sufficiently to allow installation of the guide funnel on the cask (± 0.25 inches or less)''. The alternatives considered are detailed in attachment 3. Alternative number 4, ''Modify The Pit Guides'', was determined to be the preferred alternative primarily due to considerations of simplicity, reliability, and low cost. Alternative 1, ''Rotate the impact Absorber 180 o '', was successfully performed but was considered a temporary fix that was not acceptable for a long term operational mode. The requirement to position the receiving crane accurately enough to lower the transportation cask into the pit with the redesigned guides was discussed and considered to be achievable without undue effort from the operator. The tolerance on the OD of the transfer cask was discussed (± 1/8 inch) relative to the clearance with the guides. As-built dimensions for the cask OD will be looked at to verify sufficient clearance exists with the maximum cask OD. The final design thickness of the shims under the guides will be based on the as-built cask OD dimensions and field measurements between the pit guides. The need for a ''plastic'' cover for the guides was discussed and deemed unnecessary. Thermal growth of the cask OD was calculated at 3-5 mils and considered insignificant. The possibility of reducing the OD of the guide funnel was reviewed but this was considered impractical due to the requirement for the MCO to miss the edge of the funnel in case of a MCO drop. One of the transportation casks have the lift trunions installed 3/8 inch off center. This is

  15. Retrospective Analysis of Mosh-Pit-Related Injuries.

    Science.gov (United States)

    Milsten, Andrew M; Tennyson, Joseph; Weisberg, Stacy

    2017-12-01

    Moshing is a violent form of dancing found world-wide at rock concerts, festivals, and electronic dance music events. It involves crowd surfing, shoving, and moving in a circular rotation. Moshing is a source of increased morbidity and mortality. The goal of this study was to report epidemiologic information on patient presentation rate (PPR), transport to hospital rate (TTHR), and injury patterns from patients who participated in mosh-pits. Materials and Methods Subjects were patrons from mosh-pits seeking medical care at a single venue. The events reviewed were two national concert tours which visited this venue during their tour. The eight distinct events studied occurred between 2011 and 2014. Data were collected retrospectively from prehospital patient care reports (PCRs). A single Emergency Medical Service (EMS) provided medical care at this venue. The following information was gathered from each PCR: type of injury, location of injury, treatment received, alcohol or drug use, Advanced Life Support/ALS interventions required, age and gender, disposition, minor or parent issues, as well as type of activity engaged in when injured. Attendance for the eight events ranged from 5,100 to 16,000. Total patient presentations ranged from 50 to 206 per event. Patient presentations per ten thousand (PPTT) ranged from 56 to 130. The TTHR per 10,000 ranged from seven to 20. The mean PPTT was 99 (95% CI, 77-122) and the median was 98. The mean TTHR was 16 (95% CI, 12-29) and the median TTHR was 17. Patients presenting from mosh-pits were more frequently male (57.6%; P<.004). The mean age was 20 (95% CI, 19-20). Treatment received was overwhelmingly at the Basic Life Support (BLS) level (96.8%; P<.000001). General moshing was the most common activity leading to injury. Crowd surfing was the next most significant, accounting for 20% of presentations. The most common body part injured was the head (64% of injuries). This retrospective review of mosh-pit-associated injury

  16. A single base difference between Pit-1 binding sites at the hGH promoter and locus control region specifies distinct Pit-1 conformations and functions.

    Science.gov (United States)

    Shewchuk, Brian M; Ho, Yugong; Liebhaber, Stephen A; Cooke, Nancy E

    2006-09-01

    Activation of the human growth hormone (hGH-N) gene in pituitary somatotropes is mediated by a locus control region (LCR). This LCR is composed of DNase I-hypersensitive sites (HS) located -14.5 kb to -32 kb relative to the hGH-N promoter. HSI, at -14.5 kb, is the dominant determinant of hGH-N expression and is essential for establishment of a 32-kb domain of histone acetylation that encompasses the active hGH locus. This activity is conferred by three binding sites for the POU domain transcription factor Pit-1. These Pit-1 elements are sufficient to activate hGH-N expression in the mouse pituitary. In contrast, Pit-1 sites at the hGH-N promoter are consistently unable to mediate similar activity. In the present study, we demonstrate that the functional difference between the promoter-proximal and the HSI Pit-1 binding sites can be attributed in part to a single base difference. This base affects the conformation of the Pit-1/DNA complex, and reciprocal exchange of the divergent bases between the two sets of Pit-1 elements results in a partial reversal of their transgenic activities. These data support a model in which the Pit-1 binding sites in the hGH LCR allosterically program the bound Pit-1 complex for chromatin activating functions.

  17. The Influence of Radiation on Pit Solution Chemistry as it Pertains to the Transition from Metastable to Stable Pitting in Steels.

    Energy Technology Data Exchange (ETDEWEB)

    Galuszka-Muga, Barbara

    2005-05-19

    An investigation was undertaken of the effect of gamma radiation on metastable pitting of mild carbon steels immersed in a solution similar to those existing at high level waste (HLW) deposits in the US. The object was to observe the extent to which a dosage rate of 1 Mrad/hour (10 Kgrey/hour) affected measurable electrochemical parameters such as pitting potential, open circuit potential, rate of metastable pitting and repassivation potential. Methods for reliably measuring electrochemical potentials in a high radiation field were developed. Exploratory analyses were made of the ion product release and electrolyte composition change in a confined volume simulating the conditions of a corrosion initiated pit during gamma irradiation. As expected the results indicated that the metastable pitting rate (as well as the general rate of corrosion) was significantly enhanced by a radiation field.

  18. Draft Supplemental Programmatic Environmental Impact Statement on Stockpile Stewardship and Management for a Modern Pit Facility

    International Nuclear Information System (INIS)

    2003-01-01

    The U.S. Department of Energy's (DOE) National Nuclear Security Administration (NNSA) is responsible for the safety and reliability of the U.S. nuclear weapons stockpile, including production readiness required to maintain that stockpile. Since 1989, DOE has been without the capability to produce stockpile certified plutonium pits, which are an essential component of nuclear weapons. NNSA, the Department of Defense (DOD), and Congress have highlighted the lack of long-term pit production capability as a national security issue requiring timely resolution. While a small interim capacity is currently being established at the Los Alamos National Laboratory (LANL), classified analyses indicate projected capacity requirements (number of pits to be produced over a period of time), and agility (ability to rapidly change from production of one pit type to another, ability to simultaneously produce multiple pit types, or the flexibility to produce pits of a new design in a timely manner) necessary for long-term support of the stockpile will require a long-term pit production capability. In particular, identification of a systemic problem associated with an existing pit type, class of pits, or aging phenomenon cannot be adequately responded to today, nor could it be with the small capability being established at LANL (see Section S.2 for a more detailed discussion regarding the purpose and need for a Modern Pit Facility [MPF])

  19. Numerical simulation of the double pits stress concentration in a curved casing inner surface

    Directory of Open Access Journals (Sweden)

    Wei Yan

    2016-12-01

    Full Text Available Sour or sweet oil fields development is common in recent years. Casing and tubing are usually subjected to pitting corrosion because of exposure to the strong corrosion species, such as CO2, H2S, and saline water. When the corrosion pits formed in the casing inner surface, localized stress concentration will occur and the casing strength will be degraded. Thus, it is essential to evaluate the degree of stress concentration factor accurately. This article performed a numerical simulation on double pits stress concentration factor in a curved inner surface using the finite element software ABAQUS. The results show that the stress concentration factor of double pits mainly depends on the ratio of two pits distance to the pit radius (L/R. It should not be only assessed by the absolute distance between the two pits. When the two pits are close and tangent, the maximum stress concentration factor will appear on the inner tangential edges. Stress concentration increased by double pits in a curved casing inner surface is more serious than that in a flat surface. A correction factor of 1.9 was recommended in the curved inner surface double pits stress concentration factor predict model.

  20. Observation of etch pits in Fe-36wt%Ni Invar alloy

    Science.gov (United States)

    Lu, Dong-zhu; Wu, Min-jie

    2014-07-01

    To indirectly investigate the dislocation behavior of Fe-36wt%Ni Invar alloy by the etch pit method, polished Invar specimens were etched by a solution containing 4 g copper sulfate, 20 mL hydrochloric acid, and 20 mL deionized water for 2 min. Etch pits in the etched surfaces were observed. All the etch pits in one specific grain exhibited similar shapes, which are closely related to the grain orientations. These etch pits were characterized as dislocation etch pits. It was observed that etch pits arranged along grain boundaries, gathered at grain tips and strip-like etch pit clusters passed through a number of grains in the pure Invar specimens. After the addition of a small amount of alloying elements, the identification of a single dislocation etch pit is challenging compared with the pure Invar alloy. Thus, the observation of etch pits facilitates the investigation on the dislocation behavior of the pure Invar alloy. In addition, alloying elements may affect the densities and sizes of etch pits.

  1. Structures of Bordered Pits Potentially Contributing to Isolation of a Refilled Vessel from Negative Xylem Pressure in Stems of Morus australis Poir.: Testing of the Pit Membrane Osmosis and Pit Valve Hypotheses.

    Science.gov (United States)

    Ooeda, Hiroki; Terashima, Ichiro; Taneda, Haruhiko

    2017-02-01

    Two hypotheses have been proposed to explain the mechanism preventing the refilling vessel water from being drained to the neighboring functional vessels under negative pressure. The pit membrane osmosis hypothesis proposes that the xylem parenchyma cells release polysaccharides that are impermeable to the intervessel pit membranes into the refilling vessel; this osmotically counteracts the negative pressure, thereby allowing the vessel to refill. The pit valve hypothesis proposes that gas trapped within intervessel bordered pits isolates the refilling vessel water from the surrounding functional vessels. Here, using the single-vessel method, we assessed these hypotheses in shoots of mulberry (Morus australis Poir.). First, we confirmed the occurrence of xylem refilling under negative pressure in the potted mulberry saplings. To examine the pit membrane osmosis hypothesis, we estimated the semi-permeability of pit membranes for molecules of various sizes and found that the pit membranes were not semi-permeable to polyethylene glycol of molecular mass osmosis mechanism in mulberry would be unrealistically large. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  2. Mud Pit Identification Report, Nevada Test Site, Nevada (September 2001, Rev. No. 0)

    Energy Technology Data Exchange (ETDEWEB)

    NNSA/NV

    2001-09-20

    The U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Operations Office (NNSA/NV) and the Nevada Division of Environmental Protection completed the Mud Pit Strategy, Nevada Test Site (NTS), Nevada (DOE/NV, 2001) to document a systematic process for identifying and categorizing potentially contaminated mud pits located on the NTS, and systematically evaluating them for inclusion in the Federal Facility Agreement and Consent Order (FFACO). The objectives of this report are to summarize the process used to define the six mud pit categories, identify mud pits, discuss the mud pits that do not meet FFACO entry criteria, identify mud pits for proposed FFACO entry, and describe the general mud pit distribution. Underground nuclear testing conducted since 1951 at the NTS has produced mud pits that were used for the transfer and collection of drilling mud, rock cuttings, and drilling fluids. This report documents the execution of the strategy document by examining the identification process and documenting these results. For clarification purposes, this document uses the term ''entry'' to indicate inclusion of mud pits into the FFACO and ''exclusion'' to indicate those mud pits which do not meet the ''entry'' criteria defined in this report. Based on this criteria, 257 mud pits identified that have been proposed for FFACO entry were found in 14 separate areas of the NTS. Each of the 257 mud pits proposed for FFACO entry will need to be located in the field, photographed, and documented during future Industrial Sites Project, Preliminary Assessment activities. If the field review determines that a mud pit was misidentified or improperly categorized, the appropriate FFACO modification request will be submitted for review and approval.

  3. Evidence for an explosive origin of central pit craters on Mars

    Science.gov (United States)

    Williams, Nathan R.; Bell, James F.; Christensen, Philip R.; Farmer, Jack D.

    2015-05-01

    Kilometer-scale pits are nested in the centers of many impact craters on Mars as well as on icy satellites. They have been inferred to form in the presence of a water-ice rich substrate; however, the process(es) responsible for their formation is still debated. Previous models invoke origins by either explosive excavation of potentially water-bearing crustal material, or by subsurface drainage of meltwater and/or collapse. If explosive excavation forms central pits, pit-derived ejecta should be draped around the pits, whereas internal collapse should not deposit significant material outside pit rims. Using visible wavelength images from the Mars Reconnaissance Orbiter (MRO) Context Camera (CTX) and High Resolution Imaging Science Experiment (HiRISE) instruments and thermal infrared images from the Odyssey Thermal Emission Imaging System (THEMIS) instrument, we conducted a survey to characterize, in detail, the global population of central pits in impact craters ⩾10 km in diameter. We specifically examined the morphology and thermophysical characteristics of the pits for evidence of pit ejecta. Our analysis of thermal images suggests that coarse-grained materials are distributed proximally around many central pits on the floors of their host craters. The decrease in average grain size with distance from pit rims is consistent with pit-derived ejecta. These observations and interpretations better support an explosive origin for central pits on Mars than they do an origin of subsurface meltwater drainage and collapse of the overlying substrate. A major weakness to previous explosive central pit formation models is the inability for them to form pits late enough in the impact process to be preserved. To address this, we present an alternative "melt contact model" where a central uplift brings ice-bearing substrate into contact with impact melt to generate steam explosions and excavate central pits during the impact modification stage. Theoretical calculations show

  4. Detection of simulated pitting corrosion and noises in crude oil storage tank by acoustic emission

    International Nuclear Information System (INIS)

    Shukri Mohd; Latif, N.A.; Azhar Mohd Sinin; Mohamad Daud; Abd Nasir Ibrahim

    2008-01-01

    The damage mechanisms associated with crude oil storage tanks can be complex and varied and include pitting corrosion due to presence of species such as sulphate reducing bacteria. Acoustic Emission (AE) could be used to characterise the pitting corrosion signal in crude oil storage tanks but it is extremely difficult to simulate the pitting corrosion in the laboratory using crude oil as electrolyte because crude oil is considered as non corrosive medium. In this study, induced current have been introduced onto a surface ASTM 516 steel as an electrical source to simulate the electrical noise produced during pitting corrosion process and AE sensor have been used to detect this current. It is found that AE system could detect AE signal release during current induction this current and is expected that if the exact simulation of the current magnitude produced during pitting corrosion process is made available, AE characterisation of pitting corrosion in such tank could be made possible. (Author)

  5. The role of inclusions in the pitting behaviour of maraging steel

    International Nuclear Information System (INIS)

    Ahmad, M.S.; Hussain, S.W.; Ashraf, H.

    1999-01-01

    The pitting characteristics of maraging steel in artificial seawater have been investigated electrochemically using the cyclic polarization technique. Pits were found to be associated with the inclusions present in steel. The hysteresis loop observed indicates that maraging steel has poor resistance to pitting in air saturated seawater. On examination of corroded surfaces under SEM, it is noted that the pits are always associated with inclusions, which are generally the carbonitrides of TiMo presents in maraging steel in varying quantities depending on the melting practice. In order to confirm that the pitting behavior is associated with inclusions, samples from clean maraging steel, having very low inclusion level, were tested. Such samples showed much less tendency for pitting. (author)

  6. Probability distribution of pitting corrosion depth and rate in underground pipelines: A Monte Carlo study

    Energy Technology Data Exchange (ETDEWEB)

    Caleyo, F. [Departamento de Ingenieria Metalurgica, ESIQIE, IPN, UPALM Edif. 7, Zacatenco, 07738 Mexico, D.F. (Mexico)], E-mail: fcaleyo@gmail.com; Velazquez, J.C. [Departamento de Ingenieria Metalurgica, ESIQIE, IPN, UPALM Edif. 7, Zacatenco, 07738 Mexico, D.F. (Mexico); Valor, A. [Facultad de Fisica, Universidad de La Habana, San Lazaro y L, Vedado, 10400, La Habana (Cuba); Hallen, J.M. [Departamento de Ingenieria Metalurgica, ESIQIE, IPN, UPALM Edif. 7, Zacatenco, 07738 Mexico, D.F. (Mexico)

    2009-09-15

    The probability distributions of external-corrosion pit depth and pit growth rate were investigated in underground pipelines using Monte Carlo simulations. The study combines a predictive pit growth model developed by the authors with the observed distributions of the model variables in a range of soils. Depending on the pipeline age, any of the three maximal extreme value distributions, i.e. Weibull, Frechet or Gumbel, can arise as the best fit to the pitting depth and rate data. The Frechet distribution best fits the corrosion data for long exposure periods. This can be explained by considering the long-term stabilization of the diffusion-controlled pit growth. The findings of the study provide reliability analysts with accurate information regarding the stochastic characteristics of the pitting damage in underground pipelines.

  7. Neuronal Mechanisms and Bloodflow Control of Infrared Reception in Snakes

    National Research Council Canada - National Science Library

    Goris, Richard

    2004-01-01

    The infrared pit organs of pit vipers and pythons were studied with emphasis on bloodflow in the capillary bed and its possible role as a cooling mechanism for the pit receptors stimulated by infrared (= heat...

  8. SIMULATION OF OLIVE PITS PYROLYSIS IN A ROTARY KILN PLANT

    Directory of Open Access Journals (Sweden)

    Giacobbe Braccio

    2011-01-01

    Full Text Available This work deals with the simulation of an olive pits fed rotary kiln pyrolysis plant installed in Southern Italy. The pyrolysis process was simulated by commercial software CHEMCAD. The main component of the plant, the pyrolyzer, was modelled by a Plug Flow Reactor in accordance to the kinetic laws. Products distribution and the temperature profile was calculated along reactor's axis. Simulation results have been found to fit well the experimental data of pyrolysis. Moreover, sensitivity analyses were executed to investigate the effect of biomass moisture on the pyrolysis process.

  9. Storage and Management of Open-pit Transportation Path

    Directory of Open Access Journals (Sweden)

    Jiusheng Du

    2013-07-01

    Full Text Available This paper is aiming at the actual demand of open-pit mine daily production scheduling and positioning monitoring. After extracting data from existing topographic maps and other information, it discusses the feasibility of using this data to establish thematic database. By considering the extensive application of GPS data, utilizing new spatial data types of SQL Server 2008 for data storage and management. Extracting data algorithms such as the node spatial data, the regional boundary and the path are implemented, then spatial data storage and management is also realized. It provides the basis for the production of decision-making and production cost savings.

  10. Electrochemical tests for pitting and crevice corrosion susceptibility

    International Nuclear Information System (INIS)

    Postlethwaite, J.

    1983-01-01

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

  11. Superficial drainage studies in open-pit mines

    International Nuclear Information System (INIS)

    Teixeira Junior, P.B.; Leite, C.B.B.

    1984-01-01

    Drainage studies concerning large open-pit mining projects can be of vital importance throughout the mining activity itself as they may assist in avoiding activity interruptions due to drainage problems, therefore representing substantial savings. These studies should, in fact, be carried out from the initial activity stages and shall be considered in operational, project and planning decisions in order to optimize results and reduce costs. This specific study presents a drainage study systematization proposal, enphasazing economic decision criteria. The authors comment on studies of this nature developed at the Caldas uranium mine - NUCLEBRAS. (D.J.M.) [pt

  12. The use of different techniques for determination of pitting corrosion potential of austenitic stainless steel

    International Nuclear Information System (INIS)

    Eskelinen, P.; Forsen, O.; Onnela, J.; Ylaesaari, S.; Haenninen, H.

    1992-01-01

    Three different techniques for pitting corrosion potential measurement on austenitic stainless steel (Fe18Cr10Ni) were compared: conventional polarization method, a new Avesta electrochemical corrosion measurement cell and a scratch technique. Special attention was paid to the effects of crevice corrosion during pitting corrosion potential measurement and to their elimination. Development of a rapid test technique for reliable pitting corrosion potential determination was aimed at and resulted from comparison of the different techniques

  13. Itataia's deposit - Structural zoning of a pit until the level 480 meters

    International Nuclear Information System (INIS)

    Mendonca, J.C.G.S.

    1986-01-01

    This work is part of Itataia Project-Geotechnics; in it are introduced several comments concerning the structural zoning of a pit in Itataias' phosphorous-uranipherous deposit, until the level 480 meters. The structural parameters (fractures, faults, foliations) obtained in surface and underground works were statistically treated. Stereographic projection was used to define eventual slipping into the pit. All the data were arranged in tables to make it easy the comparison with experimental pits. (author) [pt

  14. INFLUENCE OF PIT WALL ANCHORAGE ONTO ADDITIONAL DEFORMATIONS OF EXISTING BUILDINGS

    Directory of Open Access Journals (Sweden)

    Kubetskiy Valeriy Leonidovich

    2012-07-01

    Assessment of additional projected deformations of buildings located in close proximity to pits is exemplified by the specific structure of the pit support system that has active PIT [1] anchors. The authors also consider the influence produced by the structure of anchors onto the two buildings located within the area of influence of the excavation works and protected by the anchors installed underneath the foundations of the two adjacent buildings.

  15. Galvanokinetic polarization method applied to the pitting corrosion study of stainless steels

    International Nuclear Information System (INIS)

    Le Xuan, Q.; Vu Quang, K.

    1992-01-01

    Galvanokinetic (GK) polarisation method was used to study the pitting corrosion of 316L stainless steel in chloride solution. Current scan rate effect on the pitting characteristic parameters was pointed out. Specific relations between current scan rate and some pitting characteristic parameters, such as critical current density I c , stable current density I s , critical time t c , stable time t s , were established. Some advantages of the GK polarisation method were discussed

  16. Prediction of the net radon emission from a model open pit uranium mine

    International Nuclear Information System (INIS)

    Nielson, K.K.; Perkins, R.W.; Schwendiman, L.C.; Enderlin, W.I.

    1979-04-01

    Radon emission from a model open pit uranium mining operation has been estimated by applying radon exhalation fluxes measured in an open pit uranium mine to the various areas of the model mine. The model mine was defined by averaging uranium concentrations and production and procedural statistics for eight major open pit uranium mines in the Casper, Wyoming area. The resulting emission rates were 740 Ci/AFR during mining operations and 33 Ci/AFR/yr after abandonment of the mine

  17. Large heterogeneities in comet 67P as revealed by active pits from sinkhole collapse.

    Science.gov (United States)

    Vincent, Jean-Baptiste; Bodewits, Dennis; Besse, Sébastien; Sierks, Holger; Barbieri, Cesare; Lamy, Philippe; Rodrigo, Rafael; Koschny, Detlef; Rickman, Hans; Keller, Horst Uwe; Agarwal, Jessica; A'Hearn, Michael F; Auger, Anne-Thérèse; Barucci, M Antonella; Bertaux, Jean-Loup; Bertini, Ivano; Capanna, Claire; Cremonese, Gabriele; Da Deppo, Vania; Davidsson, Björn; Debei, Stefano; De Cecco, Mariolino; El-Maarry, Mohamed Ramy; Ferri, Francesca; Fornasier, Sonia; Fulle, Marco; Gaskell, Robert; Giacomini, Lorenza; Groussin, Olivier; Guilbert-Lepoutre, Aurélie; Gutierrez-Marques, P; Gutiérrez, Pedro J; Güttler, Carsten; Hoekzema, Nick; Höfner, Sebastian; Hviid, Stubbe F; Ip, Wing-Huen; Jorda, Laurent; Knollenberg, Jörg; Kovacs, Gabor; Kramm, Rainer; Kührt, Ekkehard; Küppers, Michael; La Forgia, Fiorangela; Lara, Luisa M; Lazzarin, Monica; Lee, Vicky; Leyrat, Cédric; Lin, Zhong-Yi; Lopez Moreno, Josè J; Lowry, Stephen; Magrin, Sara; Maquet, Lucie; Marchi, Simone; Marzari, Francesco; Massironi, Matteo; Michalik, Harald; Moissl, Richard; Mottola, Stefano; Naletto, Giampiero; Oklay, Nilda; Pajola, Maurizio; Preusker, Frank; Scholten, Frank; Thomas, Nicolas; Toth, Imre; Tubiana, Cecilia

    2015-07-02

    Pits have been observed on many cometary nuclei mapped by spacecraft. It has been argued that cometary pits are a signature of endogenic activity, rather than impact craters such as those on planetary and asteroid surfaces. Impact experiments and models cannot reproduce the shapes of most of the observed cometary pits, and the predicted collision rates imply that few of the pits are related to impacts. Alternative mechanisms like explosive activity have been suggested, but the driving process remains unknown. Here we report that pits on comet 67P/Churyumov-Gerasimenko are active, and probably created by a sinkhole process, possibly accompanied by outbursts. We argue that after formation, pits expand slowly in diameter, owing to sublimation-driven retreat of the walls. Therefore, pits characterize how eroded the surface is: a fresh cometary surface will have a ragged structure with many pits, while an evolved surface will look smoother. The size and spatial distribution of pits imply that large heterogeneities exist in the physical, structural or compositional properties of the first few hundred metres below the current nucleus surface.

  18. Mud Pit Risk-Based Closure Strategy Report, Nevada Test Site, Nevada, Revision 0

    Energy Technology Data Exchange (ETDEWEB)

    Brain Hoenes

    2004-08-01

    This report presents the findings of the human and ecological risk assessment for the NTS mud pits. The risk assessment utilizes data from 52 of the 270 NTS mud pits in conjunction with corroborative data from 87 other DOE mud pits associated with nuclear testing (at locations on the NTS, in the western United States, and Alaska) as well as relevant process knowledge. Based on the risk assessment findings, the report provides a strategy for further evaluation, characterization, and closure of all 270 NTS mud pit CASs using the Streamlined Approach for Environmental Restoration (SAFER).

  19. TRANSITIONS IN ELECTROCHEMICAL NOISE DURING PITTING CORROSION OF ALUMINUM IN CHLORIDE ENVIRONMENTS.

    Energy Technology Data Exchange (ETDEWEB)

    SASAKI,K.; ISAACS,H.S.; LEVY,P.W.

    2001-09-02

    Aluminum, in a chloride containing solutions close to its pitting potential, shows vigorous fluctuations in current and potential. Measurements have been made of the freely corroding potential, and the currents between interconnected electrodes. It is shown that there is a transition in the behavior of the transients. The transition occurs when multiple active pits are present and electrochemical communication occurs between them. The major source of current and potential transients is the growth process in the active pits rather than meta-stable pitting at the passive surface.

  20. Assessment of Concrete Repair Techniques for Radiologically-Contaminated Tank Farm Pump and Valve Pits

    International Nuclear Information System (INIS)

    MINTEER, D.J.

    2000-01-01

    As part of the scope of Project W-314, ''Tank Farm Restoration and Safe Operations,'' the condition of pump and valve pit walls and floors is being assessed, and repairs made as needed, to support upgrading the infrastructure necessary to safely transfer tank waste for treatment. Flaws in the surfaces of the pits (e.g., concrete crack/faults, protective coating deterioration) must be repaired to ensure containment integrity and to facilitate future decontamination of the pits. This engineering study presents a cost/risk/benefit evaluation of concrete and protective coating repair methods in pump and valve pits using various manual and remote tool systems

  1. The Space-Time Fractal Feature of Deformation at Convex Corner of Deep Foundation Pit

    Directory of Open Access Journals (Sweden)

    ZHAO Shun-li

    2016-03-01

    Full Text Available The study on the space-time feature of foundation pit deformation has important significance to ensure the stability of foundation pit engineering. In the present study, the relationship between the space-time fractal feature of foundation pit deformation and the stability of the foundation pit is expressed with simple indexes, such as the time and position of the maximum value of deformation. By combining the concrete engineering example, the fractal theory is introduced, and the correlation dimension is calculated with the measured deformation data for a period of time. By combining the concrete engineering example, the fractal theory was introduced, and used the correlation dimension calculated with the measured deformation data to analyze the space-time fractal feature of deformation at convex corner. Further researched on the relationship between the correlation dimension of the foundation pit deformation and the stability of foundation pit. The research showed that the correlation dimension could reveal the complex space-time feature of the foundation pit deformation. From the aspects of time, the correlation dimension is related to the foundation pit condition, construction disturbance, the change of supporting structure and so on, and has a certain degree of decline with time. From the aspects of space, the difference of correlation dimension between stable and unstable regions is relatively large while there is little difference in the stability region. With the correlation dimension, it is more easily to identify the stable and the unstable regions of the foundation pit, compared with the accumulated deformation.

  2. Open-pit mining of lignin waste storage

    Directory of Open Access Journals (Sweden)

    А. В. Михайлов

    2017-03-01

    Full Text Available The purpose of this paper is to develop performance criteria for fleet selection in surface mining of lignin as a raw material for factory-made fuel. The East Siberian Biotechnical Plant (ESBP proposes to close the Lignin Waste Storage (LWS at Tulun, Irkutsk Region of Russia. The LWS is a 9.6 ha facility used for the long-term storage of hydrolysis lignin and some fly ash. The project provided whole-year open-pit mining of lignin storage with one mining ledge within 3 years. Productivity – 1500 t/day or 447 000 t/year. Excavated lignin will be stockpile on the Pellet Plant territory for later processing. Part of this closure effort would involve constructing an artificial reservoir on the place of LWS. The objectives of this project were as follows: determine equipment needs and develop optimal procedures for the lignin excavation and transportation. Lignin moving may include site preparation, excavation, transportation and road surfacing. Lignin excavation is conduct by using techniques similar to those used for open-pit mining of peat. For this project, the excavator is the most important piece of equipment required for lignin removal and handling. The mining process consist of excavating the lignin (using Kraneks ЕК-270LC and hauling it to pellet plant via six off-road tractors&semitrailers (John Deere 7730& ISON-8520.

  3. Treatment of pit water from uranium mining operation

    International Nuclear Information System (INIS)

    Mouton, A.; Lafforgue, P.; Lyaudet, G.

    1984-01-01

    The pit water from uranium mines is normally treated to eliminate the soluble radium and suspended solids. The radium is precipitated together with the barium sulphate. The latter results from the reaction of barium chloride with an excess of sulphate ions. The suspended solids are flocculated by aluminium salts (chloride, polychloride). If necessary, synthetic flocculants are also used. Certain grades of pit water contain, sometimes incidentally, a few milligrams of uranium per litre. These quantities always remain too low for any direct recovery (treatment by ion exchange resins). By applying certain measures, the preceding processes can also be used to eliminate uranium. The latter is carried away by aluminium hydroxide in a very narrow zone of pH (6 to 7,4) which corresponds to the minimum solubility of the hydroxide. Depending on the characteristic of the water (pH, salinity), use is made either of aluminium sulphate or of sodium aluminate, with an addition of a base in extreme cases. This article gives various examples of applications in the Haute-Vienne, Chardon in Vendee, the Commanderie mine in Vendee, at Cerilly in Allier and at Lodeve in Herault [fr

  4. ARIES pit disassembly-safeguards issues for transparency

    International Nuclear Information System (INIS)

    Fearey, B.L.; Cremers, T.L.

    1995-01-01

    Historic changes are now occurring in U.S. nonproliferation and arms control policy. The quantity of nuclear weapons required to provide a deterrence has decreased (especially with the end of the Cold War). Further, various bilateral and multilateral treaties now require the removal of numerous nuclear weapons from the U.S. stockpile. Although the removal of such weapons appears straightforward, the final disposition of the surplus weapons-grade nuclear material must be carefully considered. Domestically, several plutonium disposition plans are now under consideration concerning long-term safety, materials accounting, environmental impact, accessibility, and long-term containment. The Automated Retirement and Integrated Extraction System (ARIES) currently under development at Los Alamos National Laboratory is one such disposition method for the disassembly of plutonium weapons components (pits). The ARIES system integrates and automates several features: disassembly of pits, consolidation of the plutonium material, on-line measurement of final products, waste streams, and long-term packaging. Clearly, in any plutonium disposition plan, the safeguards aspects of materials control and accounting and the security aspects must be carefully considered and evaluated

  5. Off-line tests on pitting damage in mercury target

    CERN Document Server

    Futakawa, M; Ishikura, S; Kogawa, H; Tsai, C C

    2003-01-01

    A liquid-mercury target system for the MW-scale target is being developed in the world. The moment the proton beams bombard the target, stress waves will be imposed on the beam window and pressure waves will be generated in the mercury by the thermally shocked heat deposition. Provided that the negative pressure generates through its propagation in the mercury target and causes cavitation in the mercury, there is the possibility for the cavitation bubbles collapse to form pits on the interface between the mercury and the target vessel wall. In order to estimate the cavitation erosion damage due to pitting, two types of off-line tests were performed: Split Hopkinson Pressure Bar (SHPB), and Magnetic IMpact Testing Machine (MIMTM). The data on the piping damage at the high cycle impacts up to 10 million were given by the MIMTM. Additionally the data obtained were compared with classical vibratory horn tests. As a result, it is confirmed that the mean depth erosion is predictable using a homologous line in the s...

  6. Soil Properties in a South Georgia, USA, Borrow Pit 40 Years After Excavation Ceased

    Science.gov (United States)

    Brevik, E. C.

    2012-04-01

    This study investigates soil properties in an abandoned sand borrow pit located about 11 km south of Valdosta, GA, USA, that was used and then abandoned with no efforts at reclamation, and compares those developing soils to natural soils surrounding the pit. The pit contains two tiers, a deep lower part and an upper terrace. There are distinct vegetative zones within the pit; three are included in this study. The lowest part of the pit is characterized by a mix of slash pines (Pinus caribaea) and deciduous trees including sweetgum (Liquidambar styraciflua) and blackgum (Nyssa biflora) with a well-developed leaf litter cover but a lack of significant underbrush or grass. Water ponds at the surface during wet periods in the lowest part of the pit. The upper terrace has sparse vegetation along its lip including a few stunted slash and longleaf (Pinus palustris) pines and a sparse lichen cover, including "deer moss" (Cladina evansii) on the ground surface, lacks leaf litter cover, and the water table is deep relative to the rest of the pit. There is a gentle slope away from this sparsely-vegetated area towards the edge of the excavation. The edge of the pit along the upper terrace has a healthy stand of mixed pine and deciduous trees similar to that found in the pit bottom, but the ground also includes a thick cover of grass (Andropogon sp.). Water ponds at the surface during wet periods here as well. Native deciduous trees including live oaks (Quercus virginiana), water oaks (Quercus nigra), and magnolias (Magnolia sp.) characterize the area outside the pit. Although soil formation over only 40 years is slight, there are distinct differences in the soils between the vegetative zones that were studied. Soil differences are attributed to differences in topographically controlled access to water and vegetation type. Study of surrounding developed soils reveals that soils within the pit still have a significant amount of development remaining before they reach equilibrium

  7. Comparative study of anticoagulant and procoagulant properties of 28 snake venoms from families Elapidae, Viperidae, and purified Russell's viper venom-factor X activator (RVV-X).

    Science.gov (United States)

    Suntravat, Montamas; Nuchprayoon, Issarang; Pérez, John C

    2010-09-15

    Snake venoms consist of numerous molecules with diverse biological functions used for capturing prey. Each component of venom has a specific target, and alters the biological function of its target. Once these molecules are identified, characterized, and cloned; they could have medical applications. The activated clotting time (ACT) and clot rate were used for screening procoagulant and anticoagulant properties of 28 snake venoms. Crude venoms from Daboia russellii siamensis, Bothrops asper, Bothrops moojeni, and one Crotalus oreganus helleri from Wrightwood, CA, had procoagulant activity. These venoms induced a significant shortening of the ACT and showed a significant increase in the clot rate when compared to the negative control. Factor X activator activity was also measured in 28 venoms, and D. r. siamensis venom was 5-6 times higher than those of B. asper, B. moojeni, and C. o. helleri from Wrightwood County. Russell's viper venom-factor X activator (RVV-X) was purified from D. r. siamensis venom, and then procoagulant activity was evaluated by the ACT and clot rate. Other venoms, Crotalus atrox and two Naja pallida, had anticoagulant activity. A significant increase in the ACT and a significant decrease in the clot rate were observed after the addition of these venoms; therefore, the venoms were considered to have anticoagulant activity. Venoms from the same species did not always have the same ACT and clot rate profiles, but the profiles were an excellent way to identify procoagulant and anticoagulant activities in snake venoms.

  8. [Clinical evaluation of fluor protector and glass-ionomer cement used as pit and fissure sealant for preventing pit and fissure caries in children].

    Science.gov (United States)

    Ji, Pei-hong; Xu, Quan-lin; Ba, Yong

    2007-08-01

    To study the clinical effect of the fluor protector and glass-ionomer cement used as pit and fissure sealant for preventing pit and fissure caries in children. 622 health permanent teeth in 6-8 years old children were divided into three groups. Children in the experimental group A (n=207,335 teeth) underwent fluor protector every six months, experimental group B(n=205, 327 teeth) with glass-ionomer cement used as pit and fissure sealant and children in the control group(n=210, 354 teeth) underwent no treatment. The incidence of caries were compared among the three groups using SPSS10.0 software package after 3 years. After 3 years, the incidence of caries in A and B experimental groups were lower than in the control group, the difference was significant (P0.05). Fluor protector and glass-ionomer cement used as pit and fissure sealant also have good clinical effect in preventing caries.

  9. Flyover Modeling of Planetary Pits - Undergraduate Student Instrument Project

    Science.gov (United States)

    Bhasin, N.; Whittaker, W.

    2015-12-01

    On the surface of the moon and Mars there are hundreds of skylights, which are collapsed holes that are believed to lead to underground caves. This research uses Vision, Inertial, and LIDAR sensors to build a high resolution model of a skylight as a landing vehicle flies overhead. We design and fabricate a pit modeling instrument to accomplish this task, implement software, and demonstrate sensing and modeling capability on a suborbital reusable launch vehicle flying over a simulated pit. Future missions on other planets and moons will explore pits and caves, led by the technology developed by this research. Sensor software utilizes modern graph-based optimization techniques to build 3D models using camera, LIDAR, and inertial data. The modeling performance was validated with a test flyover of a planetary skylight analog structure on the Masten Xombie sRLV. The trajectory profile closely follows that of autonomous planetary powered descent, including translational and rotational dynamics as well as shock and vibration. A hexagonal structure made of shipping containers provides a terrain feature that serves as an appropriate analog for the rim and upper walls of a cylindrical planetary skylight. The skylight analog floor, walls, and rim are modeled in elevation with a 96% coverage rate at 0.25m2 resolution. The inner skylight walls have 5.9cm2 color image resolution and the rims are 6.7cm2 with measurement precision superior to 1m. The multidisciplinary student team included students of all experience levels, with backgrounds in robotics, physics, computer science, systems, mechanical and electrical engineering. The team was commited to authentic scientific experimentation, and defined specific instrument requirements and measurable experiment objectives to verify successful completion.This work was made possible by the NASA Undergraduate Student Instrument Project Educational Flight Opportunity 2013 program. Additional support was provided by the sponsorship of an

  10. The transition of corrosion pitting to surface fatigue cracks in 2024-T3 aluminum alloy

    Science.gov (United States)

    Clark, Paul Nolan

    Pitting corrosion experiments were executed to characterize the dynamics. of accelerated corrosion for the combination of 2024-T3 aluminum and a 3.5% NaCl solution at room temperature. Platinum was used as a counter electrode and a silver-silver chloride electrode was used as a reference. A corrosion protocol was developed to accelerate pitting corrosion on 2024-T3 aluminum. The developed protocol allowed for the relative control of pitting depth on fatigue dog-bone specimens. A pitting damage threshold was encountered for depths beyond an average value of approximately 135mum. Corrosion fatigue experiments were performed on specimens that had been prior corroded using the developed corrosion protocol. Pitting depths from approximately 40mum-200mum were examined for fatigue characterization. Corrosion pitting to surface fatigue crack transition was captured and fatigue crack growth behavior was documented. As well as the pit to crack transition, the short crack behavior to long crack behavior transition was captured and analyzed. Fractographic analysis of corrosion fatigue specimens revealed cracks nucleating, propagating and causing subsequent failure from accelerated prior pitting corrosion damage.

  11. Variation in xylem structure from tropics to tundra: Evidence from vestured pits

    NARCIS (Netherlands)

    Jansen, S.; Baas, P.; Gasson, P.; Lens, F.; Smets, E.

    2004-01-01

    Bordered pits play an important role in permitting water flow among adjacent tracheary elements in flowering plants. Variation in the bordered pit structure is suggested to be adaptive in optimally balancing the conflict between hydraulic efficiency (conductivity) and safety from air entry at the

  12. Genetic variation of Pit -1 gene in Chinese indigenous and Western ...

    African Journals Online (AJOL)

    Genetic variation of Pit-1 gene in Chinese indigenous and Western goose populations. J Cheng, N Qiao, W Zhao, Q Xu, H Zhang, X Duan, W Ji, G Chen. Abstract. Pituitary-specific transcription factor (Pit-1, or GHF1, or POU1F1) is expressed in the pituitary gland; it regulates pituitary development and expression of the ...

  13. Intervascular pit membranes with a torus in the wood of Ulmus (Ulmaceae) and related genera

    NARCIS (Netherlands)

    Jansen, S.; Choat, B.; Vinckier, S.; Lens, F.; Schols, P.; Smets, E.

    2004-01-01

    • The distribution of intervascular pit membranes with a torus was investigated in juvenile wood samples of 19 species of Ulmus and seven related genera. • A staining solution of safranin and alcian blue (35 : 65) was recommended to distinguish torus-bearing pit membranes using light microscopy. •

  14. A New Algorithm for Determining Ultimate Pit Limits Based on Network Optimization

    Directory of Open Access Journals (Sweden)

    Ali Asghar Khodayari

    2013-12-01

    Full Text Available One of the main concerns of the mining industry is to determine ultimate pit limits. Final pit is a collection of blocks, which can be removed with maximum profit while following restrictions on the slope of the mine’s walls. The size, location and final shape of an open-pit are very important in designing the location of waste dumps, stockpiles, processing plants, access roads and other surface facilities as well as in developing a production program. There are numerous methods for designing ultimate pit limits. Some of these methods, such as floating cone algorithm, are heuristic and do not guarantee to generate optimum pit limits. Other methods, like Lerchs–Grossmann algorithm, are rigorous and always generate the true optimum pit limits. In this paper, a new rigorous algorithm is introduced. The main logic in this method is that only positive blocks, which can pay costs of their overlying non-positive blocks, are able to appear in the final pit. Those costs may be paid either by positive block itself or jointly with other positive blocks, which have the same overlying negative blocks. This logic is formulated using a network model as a Linear Programming (LP problem. This algorithm can be applied to two- and three-dimension block models. Since there are many commercial programs available for solving LP problems, pit limits in large block models can be determined easily by using this method.

  15. Pitting Corrosion Behavior of 304 SS and 316 SS Alloys in Aqueous Chloride and Bromide Solutions

    Directory of Open Access Journals (Sweden)

    Ibtehal Kareem Shakir

    2018-01-01

    Full Text Available The importance of the present work falls on the pitting corrosion behavior investigation of 304 SS and 316 SS alloys in 3.5 wt% of aqueous solution bearing with chloride and bromide anion at different solutions temperature range starting from (20-50oC due to the pitting corrosion tremendous effect on the economic, safety and materials loss due to leakage. The impact of solution temperatures on the pitting corrosion resistance at 3.5wt% (NaCl and NaBr solutions for the 304 SS and 316 SS has been investigated utilizing the cyclic polarization techniques at the potential range -400 to1000 mV vs. SCE at 40 mV/sec scan rate followed by the surface characterization employing Scanning Electron Microscope. The results show that a significant decline in the pitting corrosion potential Ep values of both stainless steel alloys in chloride and bromide solution during temperature increase attributed to the pitting corrosion potential decreased arises from the modification of the passive film properties. The surface examination using optical microscope and scanning electron microscope prove the occurring of higher pitting density over 304 SS in chloride solution than that observed in bromide solution with a non-circular lacy cover pitfall out at the center and falls inside the pits hall in comparison to the isolated circular lacy cover pit formed on 316 SS in 3.5wt% NaBr solution at 50 oC.

  16. 78 FR 44625 - Proposed Information Collection (Open Burn Pit Registry Airborne Hazard Self-Assessment...

    Science.gov (United States)

    2013-07-24

    ... DEPARTMENT OF VETERANS AFFAIRS Proposed Information Collection (Open Burn Pit Registry Airborne Hazard Self-Assessment Questionnaire) Activity; Extension of Comment Period AGENCY: Veterans Health... to ``OMB Control No. 2900--NEW, Open Burn Pit Registry Airborne Hazard Self-Assessment Questionnaire...

  17. Detection of pit fragments in fresh cherries using near infrared spectroscopy

    Science.gov (United States)

    NIR spectroscopy in the wavelength region from 900nm to 2600nm was evaluated as the basis for a rapid, non-destructive method for the detection of pits and pit fragments in fresh cherries. Partial Least Squares discriminant analysis (PLS-DA) following various spectral pretreatments was applied to sp...

  18. Extreme value statistics for pitting corrosion of old underground cast iron pipes

    International Nuclear Information System (INIS)

    Asadi, Zohreh Soltani; Melchers, Robert E.

    2017-01-01

    Many major city water supply distribution networks consist of buried cast iron pipes. In many cases the pipes are internally cement-lined and the predominant corrosion is by external pitting. This may cause leakage and eventual structural failure. It is conventional to use the Gumbel extreme value distribution to represent the statistics of maximum pits depth and to use it to estimate the probability of pipe wall perforation. Herein data obtained for maximum pit depths for large-sized (1–2 m long) samples of 10 pipes exhumed from different, apparently randomly selected, locations after 34–129 years of service are examined for consistency with the Gumbel probability distribution. This was the case for the deepest pits, but the data for less deep pits show a consistent pattern of departure from the Gumbel distribution. Some extreme pit depth data, inconsistent with the rest are interpreted as possibly caused by material imperfections. - Highlights: • A single Gumbel distribution does not describe the complete probability distribution for pits on the old cast iron pipes. • A multi-component probability distribution is required to describe all data. • Some Gumbel plots also show a small number of much deeper pits inconsistent with the other data.

  19. Decommissioning management of pit water at an uranium mine in Hunan Province

    International Nuclear Information System (INIS)

    Li Renjie

    2002-01-01

    The author introduces the influence of mining on groundwater at an uranium mine in Hunan Province, emphatically discusses the managing principles, methods and research works of pit water in decommissioning, and summaries sealing technique, construction management and the effect achieved in management of pit water

  20. Potential Multi-Canister Overpack (MCO) Cask Drop in the K West Basin South Loadout Pit

    International Nuclear Information System (INIS)

    POWERS, T.B.

    1999-01-01

    This calculation note documents the probabilistic calculation of a potential drop of a multi-canister overpack (MCO) cask or MCO cask and immersion pail at the K West Basin south loadout pit. The calculations are in support of the cask loading system (CLS) subproject alignment of CLS equipment in the K West Basin south loadout pit

  1. Rupelian (middle Oligocene) fish otoliths from the clay pit 'De Vlijt' near Winterswijk, The Netherlands

    NARCIS (Netherlands)

    Gaemers, P.A.M.; Hinsbergh, van V.W.M.

    1978-01-01

    A large, interesting otolith fauna from the Middle Oligocene was found in the clay pit 'De Vlijt' near Winterswijk by sifting large quantities of clay and by collecting large loose specimens in the clay pit. Thirty-five species and one subspecies were indentified; nine species are new, viz.

  2. The Tegelen clay-pits: a hundred year old classical locality

    NARCIS (Netherlands)

    Hoek Ostende, van den L.W.

    2004-01-01

    Having been described in 1904 by Dubois as a locality for fossil mammals, the Tegelen clay-pits are nowadays considered a ‘classical’ locality. It is the type locality of the Tiglian, a warm period of the Early Pleistocene or Late Pliocene. The pits are primarily known for their mammalian remains,

  3. Drill and Blast Performance Evaluation at the Obra Pit of Chirano ...

    African Journals Online (AJOL)

    This paper investigates the causes of inefficient fragmentation and formation of toes in the Obra pit of Chirano Gold Mines Ltd and recommends best practices in order to produce optimum fragmentation to feed the crusher at a reduced cost and to provide good working pit floors. The methods employed included: drilling ...

  4. Fishery and Ecological Investigations of Main Stem Levee Borrow Pits Along the Lower Mississippi River.

    Science.gov (United States)

    1984-12-01

    add to levee stability. V Levee Borra Pits 16. Borrow pits form a chain of water bodies along the riverward base of the 1600-mile main line levee...Sister Lake, Michigan, to be 86 pounds per acre based on rotenone treatment . 215. Standing stock estimates averaged 174 pounds per acre from 139

  5. Catastrophic windthrow in the Southern Appalachians: characteristics of pits and mounds and initial vegetation responses

    Science.gov (United States)

    Barton D. Clinton; Corey R. Baker

    2000-01-01

    We characterized pit and mound (PM) topography resulting from catastrophic wind in the Coweeta Basin, and located 48 PM’s across a variety of forest types. Our measurements included pit length, width, and depth; and mound height, thickness, and width. Species of fallen trees were...

  6. Micromorphology and systematic distribution of pit membrane thickenings in Oleaceae: Tori and pseudo-tori

    NARCIS (Netherlands)

    Rabaey, D.; Huysmans, S.; Lens, F.; Smets, E.; Jansen, S.

    2008-01-01

    Recent studies on the functional significance of pit membranes in water conducting cells have renewed general interest in their micromorphology. At least two types of pit membrane thickenings have been described in angiosperm families, i.e. genuine tori and pseudo-tori. This study explores the

  7. PREVENTION OF ACID MINE DRAINAGE GENERATION FROM OPEN-PIT MINE HIGHWALLS

    Science.gov (United States)

    Exposed, open pit mine highwalls contribute significantly to the production of acid mine drainage (AMD) thus causing environmental concerns upon closure of an operating mine. Available information on the generation of AMD from open-pit mine highwalls is very limit...

  8. Cleanup Verification Package for the 126-F-1, 184-F Powerhouse Ash Pit

    Energy Technology Data Exchange (ETDEWEB)

    S. W. Clark and H. M Sulloway

    2007-10-31

    This cleanup verification package documents completion of remedial action for the 126-F-1, 184-F Powerhouse Ash Pit. This waste site received coal ash from the 100-F Area coal-fired steam plant. Leakage of process effluent from the 116-F-14 , 107-F Retention Basins flowed south into the ash pit, contaminating the northern portion.

  9. Cleanup Verification Package for the 126-F-1, 184-F Powerhouse Ash Pit

    Energy Technology Data Exchange (ETDEWEB)

    S. W. Clark and H. M. Sulloway

    2007-09-26

    This cleanup verification package documents completion of remedial action for the 126-F-1, 184-F Powerhouse Ash Pit. This waste site received coal ash from the 100-F Area coal-fired steam plant. Leakage of process effluent from the 116-F-14 , 107-F Retention Basins flowed south into the ash pit, contaminating the northern portion.

  10. Genetic variation of Pit-1 gene in Chinese indigenous and Western ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-07-20

    Jul 20, 2009 ... Key words: Goose, single nucleotide polymorphisms (SNPs), pituitary-specific transcription factor gene (Pit-1). ... Six pairs of primers were designed according to the DNA sequence of duck Pit-1 gene .... Sample size, genotype and gene frequency in 6 goose populations for the polymorphic primer pairs.

  11. Stochastic approach to pitting-corrosion-extreme modelling in low-carbon steel

    Energy Technology Data Exchange (ETDEWEB)

    Valor, A. [Facultad de Fisica, Universidad de La Habana, San Lazaro y L, Vedado 10400, La Habana (Cuba); Caleyo, F. [Departamento de Ingenieria Metalurgica, IPN-ESIQIE, UPALM Edif. 7, Zacatenco, Mexico DF 07738 (Mexico)], E-mail: fcaleyo@gmail.com; Rivas, D.; Hallen, J.M. [Departamento de Ingenieria Metalurgica, IPN-ESIQIE, UPALM Edif. 7, Zacatenco, Mexico DF 07738 (Mexico)

    2010-03-15

    A stochastic model previously developed by the authors using Markov chains has been improved in the light of new experimental evidence. The new model has been successfully applied to reproduce the time evolution of extreme pitting corrosion depths in low-carbon steel. The model is shown to provide a better physical understanding of the pitting process.

  12. Management of Pit 9 - highlights of accomplishments and lessons learned to date

    International Nuclear Information System (INIS)

    Schwartz, F.G.

    1995-01-01

    The Pit 9 project is a U.S. Department of Energy prototype full scale demonstration to retrieve and treat buried mixed transuranic waste. The project is being managed by the DOE-Idaho Environmental Restoration Program, in conjunction with the Environmental Protection Agency Region 10 and the state of Idaho, under the Idaho National Engineering Laboratory Federal Facility Agreement and Consent Order. Pit 9 is located in the northeast corner of the Subsurface Disposal Area (SDA) of the Radioactive Waste Management Complex (RWMC) at the Idaho National Engineering Laboratory (INEL). The Pit 9 project was conceived out of the need to determine capabilities to cost effectively retrieve and treat buried radioactive and radioactive mixed waste, and obtain characterization and contaminant migration data for buried waste at the INEL. Waste was disposed in Pit 9 from November 1967 to June 1969. Pit 9, at about 380 feet by 125 feet, represents approximately one acre of surface area of the 88 acre SDA. The pit contains approximately 350,000 ft 3 of soil beneath and between the buried waste and about 250,000 ft 3 of overburden soil. The average depth of the pit from soil surface to bedrock is approximately 17.5 feet. Approximately 110,000 ft 3 of transuranic (TRU) contaminated mixed wastes from Rocky Flats and approximately 40,000 ft 3 of low level and mixed wastes from the INEL were buried in Pit 9 during this period. Pit 9 is estimated to contain over 30,000 gallons of organics (over 30% of the total organic inventory in the SDA) and approximately 66 pounds of TRU radionuclides (between 3% and 4% of the total TRU inventory in the SDA). Pit 9 was selected as a demonstration site because it was one of the last disposal pits at the INEL to receive Rocky Flats waste, disposal records are better for Pit 9 than for disposal pits and trenches from earlier points in time, and the wastes in Pit 9 are representative of the wastes disposed in the SDA

  13. CMP [Chemicals, Metals, and Pesticides] Pits: Environmental information document

    International Nuclear Information System (INIS)

    Scott, S.C.; Kolb, N.L.; Price, V.; Bledsoe, H.W.

    1986-12-01

    This document provides environmental information on postulated closure options for the Chemicals, Metals, and Pesticides (CMP) Pits at the Savannah River Plant and was developed as background technical documentation for the Department of Energy's proposed Environmental Impact Statement (EIS) on waste management activities for groundwater protection at the plant. The results of groundwater and atmospheric pathway analyses, accident analysis, and other environmental assessments discussed in this document are based upon a conservative analysis of all foreseeable scenarios as defined by the National Environmental Policy Act (40 CFR 1500-1508). The scenarios do not necessarily represent actual environmental conditions. This document is not meant to be used as a regulatory closure plan or other regulatory document to comply with required federal or state environmental regulations

  14. Electromechanical behaviour of PIT $Nb_{3}Sn$ wires for NED

    CERN Document Server

    Seeber, B; Buta, F; Flükiger, R; Boutboul, T; Scheuerlein, C; Oberli, L; Rossi, L

    2009-01-01

    The critical current vs. axial tensile strain and transverse compressive force for two PIT Nb3Sn conductors, manufactured by SMI (now EAS), has been investigated. In addition, the distribution of the critical temperature has been determined by specific heat measurements. After identical reaction heat treatments wire #B207 has a slightly broader Tc distribution than wire #B215 and less volume fraction of Nb3Sn. The behaviour under axial tensile strain is as expected, although the strain for maximum current, m, is relativly low. However the studied wires are rather sensitive to transverse compressive forces. For instance at 10 kN and 15 T the critical current is reduced to 48% of its initial value and recovers only partially after unloading.

  15. Influence of cracks and pitting corrosion on residual ultimate strength of stiffened plates

    Directory of Open Access Journals (Sweden)

    ZHANG Jing

    2018-02-01

    Full Text Available [Objectives] Ships and offshore platforms serve in the harsh sea environment for a long time. Cracks and pitting corrosion will occur in such a structure and the damage will affect its ultimate strength.[Methods] To investigate the influence of cracks and pitting corrosion on ultimate bearing capacity, the ultimate strength of a structure under axial compression is studied by using a nonlinear finite element. The mesh size of a stiffened plate with cracks and pitting corrosion is first discussed. Then the influence of the relative positions of cracks and pitting corrosion, number of corrosion points and crack length impact on the residual ultimate strength of damaged stiffened plates is discussed via a series of calculations.[Results] The results indicate that the increase in crack length and pitting corrosion significantly decreases the ultimate strength of a stiffened plate. [Conclusions] This provides a useful reference for designing and maintaining ships and offshore structures in their life cycles.

  16. Evaluation of the susceptibility to pitting corrosion of structural steels, including steels with modified surface

    International Nuclear Information System (INIS)

    Lunarska, E.; Nikiforow, K.

    2001-01-01

    Although the low alloy ferrite-perlite and bainite-martensite steels mostly undergo the general corrosion, pitting corrosion occurring under certain conditions jeopardizes the safety of installations, causing perforation of walls or initiation of crack. On the basis of electrochemical, corrosion and microscopic examinations, the conditions simulating typical industrial corrosion environments, containing Cl - ions have been selected, to which the parts of machines, devices and installation are subjected. The test parameters provide the preferential pitting corrosion without prevailing general corrosion, and provide the similar type of corrosion of different kinds of ferrite-perlite and bainite-martensite steels, including steels with modified surface layer. The proposed express method allows to evaluate the susceptibility to pitting corrosion and to evaluate the effect of surface modification on susceptibility to pitting corrosion in environments containing Cl - ions. The method may be applied for the proper selection of materials exploited under pitting corrosion conditions and for preparation of precorroded samples for mechanical testing. (author)

  17. The Effect of Calcium Treatment on Pitting Corrosion of Type 316L Austenitic Stainless steel

    International Nuclear Information System (INIS)

    Lee, Yong Heon; LeeSoo Chan; Kim, Yong Hwan; Kim, Hee San

    2001-01-01

    Pitting in chloride containing aqueous solution occurs mainly on manganese sulphide. Adding a slight amount of Ca as an alloying element prevents the MnS formation, since Ca is a stronger sulphide former than Mn. In this work, calcium treated Type 316L austenitic stainless steels have been investigated electrochemically to evaluate the effect of modified inclusions on pitting corrosion. Staircase polarization measurements were performed in 3.5% NaCl solution, where the occurrence of pits in materials caused current spikes. During staircase polarization test, steels with calcium treatment show low and discontinuous current spikes while those without calcium treatment show high and continuous current spikes. The results show that calcium treatment in Ca/S ratio of 1 ∼ 2 leads to an increase in the pitting potential of several hundred mV. A relationship between the calcium treatment and pit initiation sites was described

  18. Cavitation pitting and erosion of aluminum 6061-T6 in mineral oil water

    Science.gov (United States)

    Rao, B. C. S.; Buckley, D. H.

    1983-01-01

    Cavitation erosion studies of aluminum 6061-T6 in mineral oil and in ordinary tap water are presented. The maximum erosion rate (MDPR, or mean depth of penetration rate) in mineral oil was about four times that in water. The MDPR in mineral oil decreased continuously with time, but the MDPR in water remained approximately constant. The cavitation pits in mineral oil were of smaller diameter and depth than the pits in water. Treating the pits as spherical segments, we computed the radius r of the sphere. The logarithm of h/a, where h is the pit depth and 2a is the top width of the pit, was linear when plotted against the logarithm of 2r/h - 1.

  19. Effect of solution treatment on pitting behavior of 2205 duplex stainless steel

    Directory of Open Access Journals (Sweden)

    H. Luo

    2017-02-01

    Full Text Available The effect of solution heat treatment on pitting behavior of 2205 duplex stainless steel was investigated by EDS, potentiodynamic polarization and SECM. The contrast experiments were carried out on the original steel. The results demonstrate that for the original sample, when the potential was at the open circuit potential, there were many pitting precursor areas, due to the local breakdown of passive film on the surface, the pitting current fluctuations on the scale of pA. On the contrary, after 1100 °C solution treatment, the passive film was more stable than the original one. Therefore, the solution treatment can markedly improve the pitting resistance of 2205 duplex stainless steel due to the reduction of pitting precursor areas.

  20. Simulation of Fatigue Crack Initiation at Corrosion Pits With EDM Notches

    Science.gov (United States)

    Smith, Stephen W.; Newman, John A.; Piascik, Robert S.

    2003-01-01

    Uniaxial fatigue tests were conducted to compare the fatigue life of laboratory produced corrosion pits, similar to those observed in the shuttle main landing gear wheel bolt-hole, and an electro-discharged-machined (EDM) flaw. EDM Jaws are used to simulate corrosion pits during shuttle wheel (dynamometer) testing. The aluminum alloy, (AA 7050) laboratory fatigue tests were conducted to simulate the local stress level contained in the wheel bolt-hole. Under this high local stress condition, the EDM notch produced a fatigue life similar to test specimens containing corrosion pits of similar size. Based on the laboratory fatigue test results, the EDM Jaw (semi-circular disc shaped) produces a local stress state similar to corrosion pits and can be used to simulate a corrosion pit during the shuttle wheel dynamometer tests.

  1. Pit incubation at passive iron-nickel alloys as a stochastic process

    Energy Technology Data Exchange (ETDEWEB)

    Cristofaro, N.B. de (Instituto Nacional de Tecnologia Industrial, San Martin (Argentina). Sector Electroquimica Aplicada); Heusler, K.E. (Technische Univ. Clausthal, Clausthal-Zellerfeld (Germany, F.R.). Abt. Korrosion und Korrosionsschutz)

    1990-05-01

    The distribution functions of pit incubation times were measured with homogeneous iron-nickel alloys containing 40, 60, and 90 wt% nickel, respectively, at different electrode potentials in borate buffer, pH 7.5, after addition of 50 mM sodium chloride. The empirical moments of the distribution function are the same as for iron. Considering a general distribution function of the exponential type with a time-dependent frequency function, the logarithms of its parameters all are linearly related to the reciprocal potential difference towards the critical pitting potential. The same relationship is also observed for the mean incubation times. At constant electrode potential the mean incubation times grow longer with increasing concentration of nickel in the alloy. The ciritical pitting potentials become more positive with the nickel concentration. The independence of the kinetics of pit incubation form the nature of the metal indicates a universal mechanism of pit nucleation. (orig.).

  2. Comparison of phenolic composition of healthy apple tissues and tissues affected by bitter pit.

    Science.gov (United States)

    Zupan, Anka; Mikulic-Petkovsek, Maja; Cunja, Vlasta; Stampar, Franci; Veberic, Robert

    2013-12-11

    Bitter pit is an important Ca(2+) deficiency disorder of apple fruit (Malus domestica Borkh.), with symptoms, necrotic spots, developing during storage. The objective of this study was to determine phenolic compounds and their contents in bitter pit in comparison to healthy skin and pulp using HPLC-MS(2). The experiment was carried out on three cultivars 'Jonagored', 'Golden Delicious' and 'Pinova'. All 15 determined phenolic compounds in pulp tissues specifically affected by bitter pit were higher than those in healthy pulp. Chlorogenic acid and catechin were to 5 times higher in those affected pulp tissues. Higher content was also determined for hydroxycinnamic acids and flavanols in the peel above the bitter pit; in contrast, flavonols and anthocyanins were higher in healthy peel. Anthocyanins in healthy peel of cultivar 'Jonagored' were 10 times higher from the content in peel above the bitter pit.

  3. Remedial Action Work Plan Amchitka Island Mud Pit Closures

    Energy Technology Data Exchange (ETDEWEB)

    DOE/NV

    2001-04-05

    This remedial action work plan presents the project organization and construction procedures developed for the performance of the remedial actions at U.S. Department of Energy (DOE's) sites on Amchitka Island, Alaska. During the late1960s and early 1970s, the U.S. Department of Defense and the U.S. Atomic Energy Commission (the predecessor agency to DOE) used Amchitka Island as a site for underground nuclear tests. A total of nine sites on the Island were considered for nuclear testing; however, tests were only conducted at three sites (i.e., Long Shot in 1965, Milrow in 1969, and Cannikin in 1971). In addition to these three sites, large diameter emplacement holes were drilled in two other locations (Sites D and F) and an exploratory hole was in a third location (Site E). It was estimated that approximately 195 acres were disturbed by drilling or preparation for drilling in conjunction with these activities. The disturbed areas include access roads, spoil-disposal areas, mud pits which have impacted the environment, and an underground storage tank at the hot mix plant which was used to support asphalt-paving operations on the island. The remedial action objective for Amchitka Island is to eliminate human and ecological exposure to contaminants by capping drilling mud pits, removing the tank contents, and closing the tank in place. The remedial actions will meet State of Alaska regulations, U.S. Fish and Wildlife Service refuge management goals, address stakeholder concerns, and address the cultural beliefs and practices of the native people. The U.S. Department of Energy, Nevada Operations Office will conduct work on Amchitka Island under the authority of the Comprehensive Emergency Response, Compensation, and Liability Act. Field activities are scheduled to take place May through September 2001. The results of these activities will be presented in a subsequent Closure Report.

  4. Gas cylinder disposal pit remediation waste minimization and management

    International Nuclear Information System (INIS)

    Alas, C.A.; Solow, A.; Criswell, C.W.; Spengler, D.; Brannon, R.; Schwender, J.M.; Eckman, C.K.; Rusthoven, T.

    1995-01-01

    A remediation of a gas cylinder disposal pit at Sandia National Laboratories, New Mexico has recently been completed. The cleanup prevented possible spontaneous releases of hazardous gases from corroded cylinders that may have affected nearby active test areas at Sandia's Technical Area III. Special waste management, safety, and quality plans were developed and strictly implemented for this project. The project was conceived from a waste management perspective, and waste minimization and management were built into the planning and implementation phases. The site layout was planned to accommodate light and heavy equipment, storage of large quantities of suspect soil, and special areas to stage and treat gases and reactive chemicals removed from the pit, as well as radiation protection areas. Excavation was a tightly controlled activity using experienced gas cylinder and reactive chemical specialists. Hazardous operations were conducted at night under lights, to allow nearby daytime operations to function unhindered. The quality assurance plan provided specific control of, and documentation for, critical decisions, as well as the record of daily operations. Both hand and heavy equipment excavation techniques were utilized. Hand excavation techniques were utilized. Hand excavation techniques allows sealed glass containers to be exhumed unharmed. In the end, several dozen thermal batteries; 5 pounds (2.3 kg) of lithium metal; 6.6 pounds (3.0 kg) of rubidium metal; several kilograms of unknown chemicals; 140 cubic yards (107 cubic meters) of thorium-contaminated soil; 270 cubic yards (205 cubic meters) of chromium-contaminated soil; and 450 gas cylinders, including 97 intact cylinders containing inert, flammable, toxic, corrosive, or oxidizing gases were removed and effectively managed to minimize waste

  5. Effects of Nanoscale V-Shaped Pits on GaN-Based Light Emitting Diodes.

    Science.gov (United States)

    Chen, Shuo-Wei; Li, Heng; Chang, Chia-Jui; Lu, Tien-Chang

    2017-01-28

    This paper reviews the formation of nanoscale V-shaped pits on GaN-based light emitting diodes (LEDs) grown by the metal organic chemical vapor deposition (MOCVD) system and studies the effect of V-shaped pits on quantum efficiency. Since V-pits could provide potential barriers around threading dislocations to lessen non-radiative recombinations in such a high defect environment. In our study, multiple InGaN/GaN quantum well samples with different emission wavelengths of 380, 420, 460, and 500 nm were grown, each with different nanoscale V-shaped pits of three diameters for 150, 200, and 250 nm, respectively. It was found that the multiple quantum well (MQW) sample with larger V-pits had a lower pit density, but a relatively larger total V-pits defected area. The optimum diameter of V-pits showing the highest quantum efficiency from the MQW sample depended on the emission wavelength. MQW samples with wavelengths of 380 and 500 nm exhibited the best internal quantum efficiency (IQE) performance at the smallest V-pits area; however, the best performance for MQW samples with wavelength around 420 and 460 nm occurred when large V-pit areas were presented. Photoluminescence (PL) peak shifts and Raman shifts can provide a relationship between quantum-confined Stark effect (QCSE) and IQE, as well as a comparison between strain and IQE. The results obtained in this phenomenological study shall provide a useful guide line in making high-performance GaN-based LEDs with wide emission spectra.

  6. Modeling and simulation of pit chemistry of 304 austenitic stainless steel under applied stress in sodium chloride solution

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Yuhui, E-mail: yhhuang@ecust.edu.cn [Key Laboratory of Pressure Systems and Safety, MOE, School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai 200237 (China); Tu, Shan-Tung; Xuan, Fu-Zhen [Key Laboratory of Pressure Systems and Safety, MOE, School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai 200237 (China)

    2013-04-15

    Highlights: ► A corrosion model was developed to simulate a stressed metal surface with a pit. ► The stress state in the pit bottom was coupled with the local corrosion environment. ► An analytical expression was established for current density of deformed pit surface. ► Local deformation had a strong effect on potential and species concentration in pits. -- Abstract: A mathematical model for simulating the active dissolution of a pit on stressed metal surface had been developed. Based on active dissolution mechanism, dissolution current density on the pit surface was assumed and extended through accounting for the thermal activation energy and the multiaxial stress state in pit bottom. The influence of applied tensile stress, pit radius and temperature was addressed. The distribution of solution potential and species concentration was predicted for different applied tensile stresses based on finite element calculations.

  7. World War II, The CANOL project and the Marwell Tar Pit: a case study

    International Nuclear Information System (INIS)

    Dobrowolsky, H.

    2000-01-01

    The CANOL project was a joint U.S.-Canada undertaking during World War II. It entailed the construction of a road and pipeline from the oil fields of Norman Wells on the Mackenzie River, 960 kms over the Mackenzie Mountains to a new refinery at Whitehorse. The goal was to provide a secure supply of aviation fuel far from the menace of Japanese bombers. Initially, the pipeline was expected to operate by October 1942. In actual fact, the first gasoline was not produced in the crude distillation unit until April 24, 1944, and it was not until November 1944 that the refinery finally began producing aviation fuel. Four months later, the pipeline and the refinery were shut down. The project cost American taxpayers $ 134 million. A total of 2650 kms of pipeline was laid. During the first nine months of pipeline operation 46,000 barrels of oil was spilled, much of it directly into the Mackenzie River. Total production from the refinery, which itself cost $ 27 million, wa 866,670 barrels of products. When the refinery was shut down, most of the refinery structures were dismantled and moved, via the Alaska Highway, to the newly discovered Leduc oilfields, but buildings, tanks and hydrocarbon waste were left behind. In a 1960 report it was estimated that some four million litres of oil has been pumped into a pit located within the containment berm formerly surrounding an 80,000 barrel oil storage tank which was dismantled after the shutdown. The bureaucratic dispute about who is responsible for cleaning up has been an issue ever since. The cost of cleanup was estimated at about $ 4 million in 1994. Since the federal government, the original owners of the land , transferred the land to provincial jurisdiction in 1970, it disclaimed any responsibility for site cleanup, however, there has been some recent evidence of willingness on the part of the Department of National Defence and the Department of Indian and Northern Affairs to determine proper actions to clean up the site

  8. Critical potentials for pitting and crevice corrosion of type 304 stainless steel in NaCl solution at 423 K

    International Nuclear Information System (INIS)

    Yashiro, Hitoshi; Koshiyama, Shinichi; Tanno, Kazuo

    1991-01-01

    Critical potentials for pitting (E pit ) and crevice corrosion (E crev ) for type 304 stainless steel have been determined from long-term steady polarization tests in deaerated NaCl solutions as a function of NaCl concentration at 423 K. E pit and E crev were expressed by the conventional form: E=A-Blog[Cl - ], where A and B in volt vs. SHE were -0.19 and 0.15 for E pit and -0.20 and 0.10 for E crev , respectively. The comparison of E pit with pitting potential (E' pit ) and repassivation potential (E R,pit ), which were repeatedly determined from stepwise cyclic polarization tests, showed that E R,pit distributed less nobly than E pit especially at lower NaCl concentrations and that E pit could be described as a lower limit of Weibull's distribution function for E' pit . The similar analysis for crevice corrosion showed that the noblest value of E R,crev for its dependency on corrosion extent corresponded to E crev but the distribution in E' crev at different concentrations of NaCl could not be described by the Weibull's function with an identical shape parameter. (author)

  9. 78 FR 7860 - Initial Research on the Long-Term Health Consequences of Exposure to Burn Pits in Iraq and...

    Science.gov (United States)

    2013-02-04

    ... to Burn Pits in Iraq and Afghanistan ACTION: Notice. SUMMARY: This notice announces the preliminary... airborne hazards and burn pits, and to take related actions to promote the effective monitoring and... long-term health consequences of exposure to burn pits in Iraq and Afghanistan. FOR FURTHER INFORMATION...

  10. Developmental stages of Hepatozoon seurati (Laveran and Pettit 1911) comb. nov., a parasite of the corned viper Cerastes cerastes and the mosquito Culex pipiens from Egypt.

    Science.gov (United States)

    Morsy, Kareem; Bashtar, Abdel Rahman; Ghaffar, Fathy Abdel; Al Quraishy, Saleh; Al Hashimi, Salam; Al Ghamdi, Ali; Shazly, Mohammed

    2013-07-01

    Developmental stages of Hepatozoon seurati (Laveran and Pettit 1911) comb. nov. are described from the tissues of the corned viper Cerastes cerastes, and from the vector Culex pipiens. The parasite described in the present study is firstly recorded as Haemogregarina seurati (Laveran and Pettit 1911) in the same host. After demonstration of the sporogonous development in the mosquito vector (C. pipiens) which showed all characteristics of the genus Hepatozoon (large oocysts containing many sporocysts producing numerous sporozoites), the parasite should be transferred into the genus Hepatozoon. The infected erythrocytes measured 20 ± 0.95 × 7.3 ± 0.85 μm; while uninfected cells measured 13.3 ± 1.04 × 7.5 ± 0.16 μm. Hypertrophy and faintly stained cytoplasm are mostly occurred in infected erythrocytes. Blood stages of the parasite were found exclusively in the erythrocytes in two forms: (1) small trophozoites (10.0 ± 0.52 × 3.0 ± 0.4 μm) and (2) long (mature) sausage-shaped (16.5 ± 1.5 × 3.5 ± 0.4 μm). Merogony occurred in the endothelial cells of the blood capillaries of lung, liver, and spleen. Mature meronts was 27.6 ± 0.7 × 17.5 ± 0.5 μm in diameter and contained 20-35 merozoites (averaged in 26). These merozoites measured 16.5 ± 1.5 × 3.5 ± 0.4 μm. Syzygy and gamogony occurred in the mosquito myxocoel till the 5th day post-infection (p.i.) while sporogony took place after 15 days p.i. On the third day p.i., a large spherical macrogamete of 29.0 ± 0.8 × 20.5 ± 0.6 μm containing a distinct nucleus in association with a single microgamete were observed. The microgamete was pyriform measured 8 ± 02 μm in length. It had a prominent nucleus and a long flagellum of at least 20.4 ± 1.3 μm in length. Fertilization occurred on the 3rd to the 4th days p.i. and the formed zygote developed into an oocyst in which repeated mitotic divisions with centripetal invaginations occurred producing sporoblasts. After sporulation, each

  11. Critical pitting temperature for Type 254 SMO stainless steel in chloride solutions

    International Nuclear Information System (INIS)

    Abd El Meguid, E.A.; Abd El Latif, A.A.

    2007-01-01

    The variation with time of the open circuit potential of high molybdenum containing stainless steel (Type 254 SMO) was measured in 4% sodium chloride solution in the temperatures range 30-100 deg. C. The plot of steady state potentials as function of temperature showed an inflection at 50 deg. C, attributed to the decrease of oxygen solubility in test solution above 50 deg. C. Potentiodynamic cycling anodic polarization technique was used to determine the critical pitting potential (E pit ) and the critical protection potential (E prot ) of the steel in 4-30% NaCl solutions at temperatures between 30 and 100 deg. C. By plotting the two values versus solution temperature, the corresponding critical pitting (CPT) and the critical protection (CPrT) temperatures were determined. Both parameters decreased with increasing chloride content. Above the CPT, E pit and E prot decreased linearly with log[Cl - ]. The addition of bromide ions to the solution shifted both E pit and E prot towards positive values. In 4% NaCl, E pit increased linearly with pH in the range 1-10. The combined effect of chloride ion concentration and pH on the morphology of the pits was examined by scanning electron microscopy (SEM) following potentiodynamic cycling anodic polarization

  12. Stochastic modeling of inspection uncertainties and applications to pitting flaws in steam generator tubes

    International Nuclear Information System (INIS)

    Mao, D.; Yuan, X.-X.; Pandey, M.D.

    2009-01-01

    Steam generators (SG) are a major pressure retaining component of great safety significance in nuclear power plants. Due to various manufacturing, operation and maintenance activities, as well as material interaction with the surrounding chemical environment, the SG tubes have been subject to a number of degradation modes. Among them, the under-deposit pitting corrosion at outside surfaces of the SG tubes just on top of the tubesheet support plates has had a serious impact on the integrity of the SG tubes. This paper presents an advanced probabilistic model of pitting corrosion characterizing the inherent randomness of the pitting process and measurement uncertainties of the in-service inspection (ISI) data obtained from eddy current (EC) inspections. A Bayesian method based on Markov Chain Monte Carlo (MCMC) simulation is developed for estimating the model parameters. The proposed model is able to predict the actual pit number, the actual pit depth as well as the maximum pit depth, which is the main interest of the pitting corrosion model. (author)

  13. Embolism resistance of three boreal conifer species varies with pit structure.

    Science.gov (United States)

    Hacke, Uwe G; Jansen, Steven

    2009-01-01

    While tracheid size of conifers is often a good proxy of water transport efficiency, correlations between conifer wood structure and transport safety remain poorly understood. It is hypothesized that at least some of the variation in bordered pit and tracheid structure is associated with both transport efficiency and embolism resistance. Stem and root samples from three boreal Pinaceae species were collected to test this hypothesis. Tracheid and pit anatomy were studied using light microscopy as well as scanning and transmission electron microscopy. While tracheid size explained at least 90% of the variation in specific conductivity for stem and root samples, the strongest correlations with embolism resistance occurred at the pit level. Both torus thickness and depth of the pit chamber showed a linear increase with greater vulnerability to cavitation. Greater embolism resistance was correlated with increasing wood density and tracheid wall reinforcement. A thinner torus may be more flexible and better able to seal the pit aperture. The pit chamber depth is proportional to the distance that the margo needs to deflect for pit aspiration.

  14. Pitting growth rate in carbon steel exposed to simulated radioactive waste

    International Nuclear Information System (INIS)

    Zapp, P.E.

    1996-06-01

    Dilute high-level radioactive waste slurries can induce pitting corrosion in carbon steel tanks in which such waste is stored and processed. The waste is normally maintained with closely monitored nitrite and hydroxide concentrations known to prevent the initiation of pitting. Coupon immersion tests are being conducted in laboratory simulants of waste to determine the probability and growth rate of pitting in steel in the event of out-of-limits nitrite concentrations. Sets of about 36 carbon steel coupons have been immersed in known corrosive conditions (nitrite < 5 per cent of the established limit) at a temperature of 50 degrees C. Three sets have been removed from testing after 64, 150, and 350 days of immersion. The long immersion times introduced variability in the exposure conditions due to the evaporation and replenishment of solution. The deepest corrosive attack was measured on each coupon by optical microscopy. The deepest pits were ranked and analyzed as a type 1 extreme value distribution to extrapolate from the coupon population to the maximum expected pit depths in a waste tank structure. The data were compared to a power law for pit growth, although the deepest pits did not increase monotonically with time in the limited data set

  15. Pitting growth rate in carbon steel exposed to simulated radioactive waste

    International Nuclear Information System (INIS)

    Zapp, P.E.

    1996-01-01

    Dilute high-level radioactive waste slurries can induce pitting corrosion in carbon steel tanks in which such waste is stored and processed. The waste is normally maintained with closely monitored nitrite and hydroxide concentrations known to prevent the initiation of pitting. Coupon immersion are being conducted in laboratory simulants of waste to determine the probability and growth rate of pitting in steel in the event of below-limits nitrite concentrations. Sets of about 36 carbon steel coupons have been immersed in known corrosive conditions (nitrite < 5% of the established limit) at a temperature of 50 C. Three sets have been removed from testing after 64, 150, and 350 days of immersion. The long immersion times introduced variability in the exposure conditions due to the evaporation and replenishment of solution. The deepest corrosive attack was measured on each coupon by optical microscopy. The deepest pits were ranked and analyzed as a type 1 extreme value distribution to extrapolate from the coupon population to the maximum pit depths in a waste tank structure. The data were compared to a power law for pit growth, although the deepest pits did not increase monotonically with time in the limited data set

  16. Fracture Characteristics in a Disposal Pit on Mesita del Buey, Los Alamos National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    David T. Vaniman; Steven L. Reneau

    1998-12-01

    The characteristics of fractures in unit 2 of the Tshirege Member of the Bandelier Tuff were documented in Pit 39, a newly excavated 13.7 m deep disposal pit at Material Disposal Area G on Mesita del Buey. The average spacing between fractures is about 1.0 to 1.3 m, the average fracture aperture is about 3 to 5 mm, and the average fracture dip is about 76o to 77o. Fracture spacing and dip in Pit 39 are generally consistent with that reported from other fracture studies on the Pajarito Plateau, although the fracture apertures in Pit 39 are less than reported elsewhere. Measured fracture orientations are strongly affected by biases imparted by the orientations of the pit walls, which, combined with a small data set, make identification of potential preferred orientations dlfflcult. The most prominent fracture orientations observed in Pit 39, about E-W and N20E, are often not well represented elsewhere on the Pajarito Plateau. Fracture fills contain smectite to about 3 m depth, and calcite and opal may occur at all depths, principally associated with roots or root fossils (rhizoliths). Roots of pifion pine extend in fractures to the bottom of the pit along the north side, perhaps indicating a zone of preferred infiltration of water. Finely powdered tuff with clay-sized particles occurs within a number of fractures and may record abrasive disaggregation associated with small amounts of displacement on minor local faults.

  17. Initiation and inhibition of pitting corrosion on reinforcing steel under natural corrosion conditions

    Energy Technology Data Exchange (ETDEWEB)

    Abd El Wanees, S., E-mail: s_wanees@yahoo.com [Chemistry Department, Faculty of Science, University of Tabuk, Tabuk (Saudi Arabia); Chemistry Department, Faculty of Science, Zagazig University, Zagazig 44519 (Egypt); Bahgat Radwan, A. [Center for Advanced Materials, Qatar University, Doha 2713 (Qatar); Alsharif, M.A. [Chemistry Department, Faculty of Science, University of Tabuk, Tabuk (Saudi Arabia); Abd El Haleem, S.M. [Chemistry Department, Faculty of Science, Zagazig University, Zagazig 44519 (Egypt)

    2017-04-01

    Initiation and inhibition of pitting corrosion on reinforcing steel in saturated, naturally aerated Ca(OH){sub 2} solutions, under natural corrosion conditions, are followed through measurements of corrosion current, electrochemical impedance spectroscopy and SEM investigation. Induction period for pit initiation and limiting corrosion current for pit propagation are found to depend on aggressive salt anion and cation-types, as well as, concentration. Ammonium chlorides and sulfates are more corrosive than the corresponding sodium salts. Benzotriazole and two of its derivatives are found to be good inhibitors for pitting corrosion of reinforcing steel. Adsorption of these compounds follows a Langmuir adsorption isotherm. The thermodynamic functions ΔE{sup ∗}, ΔH{sup ∗} and ΔS{sup ∗} for pitting corrosion processes in the absence and presence of inhibitor are calculated and discussed. - Highlights: • Cl{sup −} and SO{sub 4} {sup 2-} induce pitting corrosion on passive reinforcing steel. • Initiation and propagation of pitting depend on cation and anion types. • Inhibition is based on adsorption according to Langmuir isotherm.

  18. Pitting Corrosion of Ni3(Si,Ti+2Cr Intermetallic Compound at Various Chloride Concentrations

    Directory of Open Access Journals (Sweden)

    Gadang Priyotomo

    2014-05-01

    Full Text Available The pitting corrosion of Ni3(Si,Ti with 2 at% Cr containing two regions of a Ni3(Si,Ti single-phase of L12 structure and a mixture phase of of (L12 +Niss was investigated as function of chloride concentrations by using a polarization method, scanning electron microscope and energy dispersive X-Ray spectroscopy in neutral sodium chloride solutions at 293 K.  The pitting corrosion of Ni3(Si,Ti with and without the addition of aluminium and type C276 alloy were also studied under the same experimental condition for the comparison.  The pitting potential obtained for the Ni3(Si,Ti with 2 at% Cr decreased with increasing chloride concentration.  The specific pitting potentials and the pitting potentials were decreased in the order of C276 alloy > Ni3(Si,Ti > Ni3(Si,Ti + 2Cr > Ni3(Si,Ti + 4Al, which means that the pitting corrosion resistance of Ni3(Si,Ti with 2 at% Cr was higher than Ni3(Si,Ti with 4 at% Al, but lower than that of Ni3(Si,Ti.  A critical chloride concentration of Ni3(Si,Ti with 2 at% Cr was found to be higher than that of Ni3(Si,Ti with at% Al. In addition, the presence of high concentration for oxygen indicates the occurrence of pit formation.

  19. Algorithms for detecting cherry pits on the basis of transmittance mode hyperspectral data

    Science.gov (United States)

    Siedliska, Anna; Zubik, Monika; Baranowski, Piotr; Mazurek, Wojciech

    2017-10-01

    The suitability of the hyperspectral transmittance imaging technique was assessed in terms of detecting the internal intrusions (pits and their fragments) in cherries. Herein, hyperspectral transmission images were acquired in the visible and near-infrared range (450-1000 nm) from pitted and intact cherries of three popular cultivars: `Łutówka', `Pandy 103', and `Groniasta', differing by soluble solid content. The hyperspectral transmittance data of fresh cherries were used to determine the influence of differing soluble solid content in fruit tissues on pit detection effectiveness. Models for predicting the soluble solid content of cherries were also developed. The principal component analysis and the second derivative pre-treatment of the hyperspectral data were used to construct the supervised classification models. In this study, five classifiers were tested for pit detection. From all the classifiers studied, the best prediction accuracies for the whole pit or pit fragment detection were obtained via the backpropagation neural networks model (87.6% of correctly classified instances for the training/test set and 81.4% for the validation set). The accuracy of distinguishing between drilled and intact cherries was close to 96%. These results showed that the hyperspectral transmittance imaging technique is feasible and useful for the non-destructive detection of pits in cherries.

  20. Pitting growth rate in carbon steel exposed to simulated radioactive waste

    International Nuclear Information System (INIS)

    Zapp, P.E.

    1995-01-01

    Dilute high-level radioactive waste slurries can induce pitting corrosion in carbon steel tanks in which such waste is stored and processed. The waste is normally maintained with closely monitored nitrite and hydroxide concentrations known to prevent the initiation of pitting. Coupon immersion are being conducted in laboratory simulants of waste to determine the probability and growth rate of pitting in steel in the event of below-limits nitrite concentrations. Sets of about 36 carbon steel coupons have been immersed in known corrosive conditions (nitrite < 5% of the established limit) at a temperature of 50 C. Three sets have been removed from testing after 64, 150, and 350 days of immersion. The long immersion times introduced variability in the exposure conditions due to the evaporation and replenishment of solution. The deepest corrosive attack was measured one each coupon by optical microscopy. The deepest pits were ranked and analyzed as a type 1 extreme value distribution to extrapolate from the coupon population to the maximum pit depths in a waste tank structure. The data were compared to a power law for pit growth, although the deepest pits did not increase monotonically with time in the limited data set

  1. Detection of Trichomonas vaginalis DNA by Use of Self-Obtained Vaginal Swabs with the BD ProbeTec Qx Assay on the BD Viper System

    Science.gov (United States)

    Williams, James A.; Taylor, Stephanie N.; Cammarata, Catherine L.; Rivers, Charles A.; Body, Barbara A.; Nye, Melinda; Fuller, Deanna; Schwebke, Jane R.; Barnes, Mathilda; Gaydos, Charlotte A.

    2014-01-01

    Trichomonas vaginalis is the most prevalent nonviral sexually transmitted infection worldwide, and improved diagnostic methods are critical for controlling this pathogen. Diagnostic assays that can be used in conjunction with routine chlamydia/gonorrhea nucleic acid-based screening are likely to have the most impact on disease control. Here we describe the performance of the new BD T. vaginalis Qx (TVQ) amplified DNA assay, which can be performed on the automated BD Viper system. We focus on data from vaginal swab samples, since this is the specimen type routinely used for traditional trichomonas testing and the recommended specimen type for chlamydia/gonorrhea screening. Vaginal swabs were obtained from women attending sexually transmitted disease or family planning clinics at 7 sites. Patient-collected vaginal swabs were tested by the TVQ assay, and the Aptima T. vaginalis (ATV) assay was performed using clinician-collected vaginal swabs. Additional clinician-collected vaginal swabs were used for the wet mount and culture methods. Analyses included comparisons versus the patient infection status (PIS) defined by positive results with the wet mount method or culture, direct comparisons assessed with κ scores, and latent class analysis (LCA) as an unbiased estimator of test accuracy. Data from 838 women, 116 of whom were infected with T. vaginalis, were analyzed. The TVQ assay sensitivity and specificity estimates based on the PIS were 98.3% and 99.0%, respectively. The TVQ assay was similar to the ATV assay (κ = 0.938) in direct analysis. LCA estimated the TVQ sensitivity and specificity as 98.3 and 99.6%, respectively. The TVQ assay performed well using self-collected vaginal swabs, the optimal sample type, as recommended by the CDC for chlamydia/gonorrhea screening among women. PMID:24391200

  2. Inhibition of secretary PLA₂--VRV-PL-VIIIa of Russell's viper venom by standard aqueous stem bark extract of Mangifera indica L.

    Science.gov (United States)

    Dhananjaya, B L; Sudarshan, S

    2015-03-01

    The aqueous extract of Mangifera indica is known to possess anti-snake venom activities. However, its inhibitory potency and mechanism of action on multi-toxic phospholipases A2s, which are the most toxic and lethal component of snake venom is still unknown. Therefore, this study was carried out to evaluate the modulatory effect of standard aqueous bark extract of M. indica on VRV-PL-VIIIa of Indian Russells viper venom. Mangifera indica extract dose dependently inhibited the GIIB sPLA2 (VRV-PL-VIIIa) activity with an IC50 value of 6.8±0.3 μg/ml. M. indica extract effectively inhibited the indirect hemolytic activity up to 96% at ~40 μg/ml concentration. Further, M. indica extract at different concentrations (0-50 μg/ml) inhibited the edema formed in a dose dependent manner. It was found that there was no relieve of inhibitory effect of the extract when examined as a function of increased substrate and calcium concentration. The inhibition was irreversible as evident from binding studies. The in vitro inhibition is well correlated with in situ and in vivo edema inducing activities. As the inhibition is independent of substrate, calcium concentration and was irreversible, it can be concluded that M. indica extracts mode of inhibition could be due to direct interaction of components present in the extract with PLA2 enzyme. In conclusion, the aqueous extract of M. indica effectively inhibits svPLA2 (Snake venom phospholipase A2) enzymatic and its associated toxic activities, which substantiate its anti-snake venom properties. Further in-depth studies are interesting to known on the role and mechanism of the principal inhibitory constituents present in the extract, so as to develop them into potent anti-snake venom and as an anti-inflammatory agent.

  3. Differential procoagulant effects of saw-scaled viper (Serpentes: Viperidae: Echis) snake venoms on human plasma and the narrow taxonomic ranges of antivenom efficacies.

    Science.gov (United States)

    Rogalski, Aymeric; Soerensen, Christoffer; Op den Brouw, Bianca; Lister, Callum; Dashevsky, Daniel; Arbuckle, Kevin; Gloria, Alexandra; Zdenek, Christina N; Casewell, Nicholas R; Gutiérrez, José María; Wüster, Wolfgang; Ali, Syed A; Masci, Paul; Rowley, Paul; Frank, Nathaniel; Fry, Bryan G

    2017-10-05

    Saw-scaled vipers (genus Echis) are one of the leading causes of snakebite morbidity and mortality in parts of Sub-Saharan Africa, the Middle East, and vast regions of Asia, constituting a public health burden exceeding that of almost any other snake genus globally. Venom-induced consumption coagulopathy, owing to the action of potent procoagulant toxins, is one of the most relevant clinical manifestations of envenomings by Echis spp. Clinical experience and prior studies examining a limited range of venoms and restricted antivenoms have demonstrated for some antivenoms an extreme lack of antivenom cross-reactivity between different species of this genus, sometimes resulting in catastrophic treatment failure. This study undertook the most comprehensive testing of Echis venom effects upon the coagulation of human plasma, and also the broadest examination of antivenom potency and cross-reactivity, to-date. 10 Echis species/populations and four antivenoms (two African, two Asian) were studied. The results indicate that the venoms are, in general, potently procoagulant but that the relative dependence on calcium or phospholipid cofactors is highly variable. Additionally, three out of the four antivenoms tested demonstrated only a very narrow taxonomic range of effectiveness in preventing coagulopathy, with only the SAIMR antivenom displaying significant levels of cross-reactivity. These results were in conflict with previous studies using prolonged preincubation of antivenom with venom to suggest effective cross-reactivity levels for the ICP Echi-Tab antivenom. These findings both inform upon potential clinical effects of envenomation in humans and highlight the extreme limitations of available treatment. It is hoped that this will spur efforts into the development of antivenoms with more comprehensive coverage for bites not only from wild snakes but also from specimens widely kept in zoological collections. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Atypical pit craters on Mars: new insights from THEMIS, CTX and HiRISE observations

    Science.gov (United States)

    Cushing, Glen; Okubo, Chris H.; Titus, Timothy N.

    2015-01-01

    More than 100 pit craters in the Tharsis region of Mars exhibit morphologies, diameters and thermal behaviors that diverge from the much larger bowl-shaped pit craters that occur in most regions across Mars. These Atypical Pit Craters (APCs) generally have sharp and distinct rims, vertical or overhanging walls that extend down to their floors, surface diameters of ~50-350 m, and high depth-to-diameter (d/D) ratios that are usually greater than 0.3 (which is an upper-range value for impacts and bowl-shaped pit craters), and can exceed values of 1.8. Observations by the Mars Odyssey THermal Emission Imaging System (THEMIS) show that APC floor temperatures are warmer at night, and fluctuate with much lower diurnal amplitudes than nearby surfaces or adjacent bowl-shaped pit craters. Kīlauea volcano, Hawai'i, hosts pit craters that formed through subsurface collapse into active volcanic dikes, resulting in pits that can appear morphologically analogous to either APCs or bowl-shaped pit craters. Partially-drained dikes are sometimes exposed within the lower walls and floors of these terrestrial APC analogs and can form extensive cave systems with unique microclimates. Similar caves in martian pit craters are of great interest for astrobiology. This study uses new observations by the Mars Reconnaissance Orbiter (MRO) High Resolution Imaging Science Experiment (HiRISE) and Context Camera (CTX) to refine previous work where seven APCs were described from lower-resolution THEMIS visible-wavelength (VIS) observations. Here, we identify locations of 115 APCs, map their distribution across the Tharsis region, characterize their internal morphologies with high-resolution observations, and discuss possible formation mechanisms.

  5. In situ vitrification demonstration at Pit 1, Oak Ridge National Laboratory. Volume 2: Site characterization report of the Pit 1 area

    International Nuclear Information System (INIS)

    Spalding, B.P.; Bogle, M.A.; Cline, S.R.; Naney, M.T.; Gu, B.

    1997-12-01

    A treatability study was initiated in October 1993, initially encompassing the application of in situ vitrification (ISV) to at least two segments of Oak Ridge National Laboratory (ORNL) seepage Pit 1 by the end of fiscal year (FY) 1995. This treatability study was to have supported a possible Interim Record of Decision (IROD) or removal action for closure of one or more of the seepage pits and trenches as early as FY 1997. The Remedial Investigation/Feasibility Study for Waste Area Grouping (WAG) 7, which contains these seven seepage pits and trenches, will probably not begin until after the year 2000. This treatability study will establish the field-scale technical performance of ISV for (1) attaining the required depth, nominally 15 ft, to incorporate source contamination within and beneath the pits; (2) demonstrating field capability to overlap melt settings that are necessary to achieve fused, melted segments of the source contamination; (3) demonstrating off-gas handling technology for accommodating and minimizing the volatilization of 137 Cs; (4) demonstrating adequate site characterization techniques to predict ISV melting kinetics, processing temperatures, and product durability; and (5) promoting public acceptance of ISV technology by demonstrating its safety, implementability, site impacts, and air emissions and by coordinating the treatability study within the regulatory closure process. This report summarizes the site characterization information gathered through the end of September 1996 which supports the planning and assessment of ISV for Pit 1 (objective 4 above)

  6. In situ vitrification demonstration at Pit 1, Oak Ridge National Laboratory. Volume 2: Site characterization report of the Pit 1 area

    Energy Technology Data Exchange (ETDEWEB)

    Spalding, B.P.; Bogle, M.A.; Cline, S.R.; Naney, M.T.; Gu, B.

    1997-12-01

    A treatability study was initiated in October 1993, initially encompassing the application of in situ vitrification (ISV) to at least two segments of Oak Ridge National Laboratory (ORNL) seepage Pit 1 by the end of fiscal year (FY) 1995. This treatability study was to have supported a possible Interim Record of Decision (IROD) or removal action for closure of one or more of the seepage pits and trenches as early as FY 1997. The Remedial Investigation/Feasibility Study for Waste Area Grouping (WAG) 7, which contains these seven seepage pits and trenches, will probably not begin until after the year 2000. This treatability study will establish the field-scale technical performance of ISV for (1) attaining the required depth, nominally 15 ft, to incorporate source contamination within and beneath the pits; (2) demonstrating field capability to overlap melt settings that are necessary to achieve fused, melted segments of the source contamination; (3) demonstrating off-gas handling technology for accommodating and minimizing the volatilization of {sup 137}Cs; (4) demonstrating adequate site characterization techniques to predict ISV melting kinetics, processing temperatures, and product durability; and (5) promoting public acceptance of ISV technology by demonstrating its safety, implementability, site impacts, and air emissions and by coordinating the treatability study within the regulatory closure process. This report summarizes the site characterization information gathered through the end of September 1996 which supports the planning and assessment of ISV for Pit 1 (objective 4 above).

  7. Study on Electro-Polishing Process by Niobium-Plate Sample With Artificial Pits

    Energy Technology Data Exchange (ETDEWEB)

    T. Saeki, H. Hayano, S. Kato, M. Nishiwaki, M. Sawabe, W.A. Clemens, R.L. Geng, R. Manus, P.V. Tyagi

    2011-07-01

    The Electro-polishing (EP) process is the best candidate of final surface-treatment for the production of ILC cavities. Nevertheless, the development of defects on the inner-surface of the Superconducting RF cavity during EP process has not been studied by experimental method. We made artificial pits on the surface of a Nb-plate sample and observed the development of the pit-shapes after each step of 30um-EP process where 120um was removed by EP in total. This article describes the results of this EP-test of Nb-sample with artificial pits.

  8. Optimal Growth Conditions for Selective Ge Islands Positioning on Pit-Patterned Si(001

    Directory of Open Access Journals (Sweden)

    Bergamaschini R

    2010-01-01

    Full Text Available Abstract We investigate ordered nucleation of Ge islands on pit-patterned Si(001 using an original hybrid Kinetic Monte Carlo model. The method allows us to explore long time-scale evolution while using large simulation cells. We analyze the possibility to achieve selective nucleation and island homogeneity as a function of the various parameters (flux, temperature, pit period able to influence the growth process. The presence of an optimal condition where the atomic diffusivity is sufficient to guarantee nucleation only within pits, but not so large to induce significant Ostwald ripening, is clearly demonstrated.

  9. The effect of thermal preoxidation on the pitting susceptibility of steel Kh18N10T

    International Nuclear Information System (INIS)

    Zimina, T.Yu.; Tselykh, O.G.; Oshe, E.K.

    2004-01-01

    The effect of preliminary thermal oxidation of steel Kh18N10T in the air at temperatures of 100-775 Deg C on the tendency to pitting corrosion is under study. It is shown that a pitting corrosion potential of the steel is dependent on the defectiveness of preliminarily formed surface thermal oxides. The oxidation at temperatures of 100-300 Deg C, that forms rhombohedral type α-(Fe, Cr) 2 O 3 oxides with low deviation from stoichiometry, results in a decrease of steel tendency to pitting corrosion. The oxidation at higher temperatures deteriorates corrosion resistance of the steel [ru

  10. Effect of chloride concentration and pH on pitting corrosion of waste package container materials

    International Nuclear Information System (INIS)

    Roy, A.K.; Fleming, D.L.; Gordon, S.R.

    1996-12-01

    Electrochemical cyclic potentiodynamic polarization experiments were performed on several candidate waste package container materials to evaluate their susceptibility to pitting corrosion at 90 degrees C in aqueous environments relevant to the potential underground high-level nuclear waste repository. Results indicate that of all the materials tested, Alloy C-22 and Ti Grade-12 exhibited the maximum corrosion resistance, showing no pitting or observable corrosion in any environment tested. Efforts were also made to study the effect of chloride ion concentration and pH on the measured corrosion potential (Ecorr), critical pitting and protection potential values

  11. Inhibiting pitting corrosion in carbon steel exposed to dilute radioactive waste slurries

    International Nuclear Information System (INIS)

    Zapp, P.E.; Hobbs, D.T.

    1991-01-01

    Dilute caustic high-level radioactive waste slurries can induce pitting corrosion in carbon steel. Cyclic potentiodynamic polarization tests were conducted in simulated and actual waste solutions to determine minimum concentrations of sodium nitrate which inhibit pitting in ASTM A537 class 1 steel exposed to these solutions. Susceptibility to pitting was assessed through microscopic inspection of specimens and inspection of polarization scans. Long-term coupon immersion tests were conducted to verify the nitrite concentrations established by the cyclic potentiodynamic polarization tests. The minimum effective nitrite concentration is expressed as a function of the waste nitrate concentration and temperature

  12. Microstructure and pitting corrosion of 13CrNiMo weld metals

    International Nuclear Information System (INIS)

    Bilmes, P.D.; Llorente, C.L.; Saire Huaman, L.; Gassa, L.M.; Gervasi, C.A.

    2006-01-01

    Cyclic potentiodynamic measurements and scanning electron microscopy were used to analyze susceptibility to pitting corrosion of 13CrNiMo weld metals. In order to carry out a critical assessment of the influence of microstructural factors on localized corrosion, different heat treatments were applied to the alloys under investigation. Volume fractions of austenite in tempered conditions as well as the amount and size of precipitated carbides strongly affect pitting resistance. Characteristic potentials (pitting potential and repassivation potential) increase according to the retained austenite content. Results can be discussed in terms of a model that describes the structural refinement resulting from a double-tempering procedure

  13. Experimental and theoretic investigations of thermal behavior of a seasonal water pit heat storage

    DEFF Research Database (Denmark)

    Fan, Jianhua; Huang, Junpeng; Chatzidiakos, Angelos

    Seasonal heat storages are considered essential for district heating systems because they offer flexibility for the system to integrate different fluctuating renewable energy sources. Water pit thermal storages (PTES) have been successfully implemented in solar district heating plants in Denmark....... Thermal behavior of a 75,000 m3 water pit heat storage in Marstal solar heating plant was investigated experimentally and numerically. Temperatures at different levels of the water pit storage and temperatures at different depths of the ground around the storage were monitored and analyzed. A simulation...

  14. Markkinointiviestinnän suunnitelma : Case: Pitäjän Kukka ja Kivipalvelu Oy

    OpenAIRE

    Ryhänen, Tanja; Pihlajamaa, Saara

    2010-01-01

    Tämän toiminnallisen opinnäytetyön tavoitteena oli laatia markkinointiviestintäsuunnitelma pienyritykselle. Suunnitelmassa rakennettiin Pitäjän Kukka ja Kivipalvelu Oy:lle markkinoinnin perusvalmiudet. Lisäksi työ pyrittiin toteuttamaan toimintamalliksi muille pienyrityksille. Opinnäytetyö tehtiin toimeksiantona Pitäjän Kukka ja Kivipalvelu Oy:lle, joka toimii hautausalalla. Työssä tutustuttiin Pitäjän Kukka ja Kivipalvelu Oy:n toimialaan ja toimintaan. Yritys tarjoaa muun muassa hautakivitöi...

  15. KW basin backwash pit sludge measurement/video

    International Nuclear Information System (INIS)

    Dodd, E.N. Jr.

    1994-01-01

    The purpose of this procedure is to gather visual and depth information and monitor underwater activities in the 105-KW SFBWP and transfer channel. Profile lighting (the use of lighting and shadows to show the surface contour) will be used to assess the contour of the sludge surface. Select measurements will also be taken to determine the actual sludge depth. The control/video station will be setup outside the radiation area or in lowest possible exposure area to reduce personnel exposure (ALARA). This procedure is to provide a mechanism to assist in fully characterizing the volume and surface topology of the sludge currently deposited in the sandfilter backwash pit (SFBWP). Surveillance Systems Engineering (SSE) personnel will gather visual information utilizing a closed circuit television (CCTV) color camera, mounted to stainless steel extension poles. Connections allow the camera to be connected with a pan and tilt to allow better positioning capabilities and to get good landscape profiling of the sediment surface. The information will be videotaped to a one-half inch NTSC or Y/C format. Underwater lighting will be accomplished by means of 500 watt underwater lamps

  16. EARTHSAWtm IN-SITU CONTAINMENT OF PITS AND TRENCHES

    Energy Technology Data Exchange (ETDEWEB)

    Ernest E. Carter, P.E.

    2002-09-20

    EarthSaw{trademark} is a proposed technology for construction of uniform high quality barriers under and around pits and trenches containing buried radioactive waste without excavating or disturbing the waste. The method works by digging a deep vertical trench around the perimeter of a site, filling that trench with high specific gravity grout sealant, and then cutting a horizontal bottom pathway at the base of the trench with a simple cable saw mechanism. The severed block of earth becomes buoyant in the grout and floats on a thick layer of grout, which then cures into an impermeable barrier. The ''Interim Report on task 1 and 2'' which is incorporated into this report as appendix A, provided theoretical derivations, field validation of formulas, a detailed quantitative engineering description of the technique, engineering drawings of the hardware, and a computer model of how the process would perform in a wide variety of soil conditions common to DOE waste burial sites. The accomplishments of task 1 and 2 are also summarized herein Task 3 work product provides a comprehensive field test plan in Appendix B and a health and safety plan in Appendix C and proposal for a field-scale demonstration of the EarthSaw barrier technology. The final report on the subcontracted stress analysis is provided in Appendix D. A copy of the unified computer model is provided as individual non-functional images of each sheet of the spreadsheet and separately as a Microsoft Excel 2000 file.

  17. EXCAVATION OF PITS (CHANNELS BY IMPACT OF PULSE POWER LOADING

    Directory of Open Access Journals (Sweden)

    Anakhaev Koshkinbai Nazirovich

    2017-08-01

    Full Text Available The paper provides an innovative hydromechanical solution of the problem of profiles development of pits and channels by impact of pulse (blasting power load on a surface of homogeneous soil mass, for example, when excavating solid rocks, frozen soil, etc. Thus, soil would be considered as an ideal heavy liquid (disregarding its mechanical strength and plastic properties. The solution of this problem is achieved by the method of consecutive conformal mappings of physical flow region (in the form of Kirchhoff complex on the region of complex potential (in the form of a rectangle. Thus, the new technique of geometrical image generation of the latter in the presence in the flow region of a fixed point with discontinuous variations of pressure head-flow function and the direction of speed of flow and representation of an elliptic sine of Jacobi by means of elementary functions are used. The received analytical functional dependencies allow to determine an outline of a funnel of the soil ejection and all the required hydromechanical characteristics of flow (head-flow function, function of flow, speed of flow, etc.. Thus, the soil ejection funnel outline (for a benchmark problem completely coincides with subproduct of the known rigorous solution of Lavrentyev-Kuznetsov.

  18. EARTHSAWtm IN-SITU CONTAINMENT OF PITS AND TRENCHES

    International Nuclear Information System (INIS)

    Ernest E. Carter, P.E.

    2002-01-01

    EarthSaw(trademark) is a proposed technology for construction of uniform high quality barriers under and around pits and trenches containing buried radioactive waste without excavating or disturbing the waste. The method works by digging a deep vertical trench around the perimeter of a site, filling that trench with high specific gravity grout sealant, and then cutting a horizontal bottom pathway at the base of the trench with a simple cable saw mechanism. The severed block of earth becomes buoyant in the grout and floats on a thick layer of grout, which then cures into an impermeable barrier. The ''Interim Report on task 1 and 2'' which is incorporated into this report as appendix A, provided theoretical derivations, field validation of formulas, a detailed quantitative engineering description of the technique, engineering drawings of the hardware, and a computer model of how the process would perform in a wide variety of soil conditions common to DOE waste burial sites. The accomplishments of task 1 and 2 are also summarized herein Task 3 work product provides a comprehensive field test plan in Appendix B and a health and safety plan in Appendix C and proposal for a field-scale demonstration of the EarthSaw barrier technology. The final report on the subcontracted stress analysis is provided in Appendix D. A copy of the unified computer model is provided as individual non-functional images of each sheet of the spreadsheet and separately as a Microsoft Excel 2000 file

  19. Pit Latrine Fecal Sludge Resistance Using a Dynamic Cone Penetrometer in Low Income Areas in Mzuzu City, Malawi.

    Science.gov (United States)

    Chirwa, Charles F C; Hall, Ralph P; Krometis, Leigh-Anne H; Vance, Eric A; Edwards, Adam; Guan, Ting; Holm, Rochelle H

    2017-02-03

    Pit latrines can provide improved household sanitation, but without effective and inexpensive emptying options, they are often abandoned once full and may pose a public health threat. Emptying techniques can be difficult, as the sludge contents of each pit latrine are different. The design of effective emptying techniques (e.g., pumps) is limited by a lack of data characterizing typical in situ latrine sludge resistance. This investigation aimed to better understand the community education and technical engineering needs necessary to improve pit latrine management. In low income areas within Mzuzu city, Malawi, 300 pit latrines from three distinct areas were assessed using a dynamic cone penetrometer to quantify fecal sludge strength, and household members were surveyed to determine their knowledge of desludging procedures and practices likely to impact fecal sludge characteristics. The results demonstrate that there is a significant difference in sludge strength between lined and unlined pits within a defined area, though sludge hardened with depth, regardless of the pit type or region. There was only limited association between cone penetration depth and household survey data. To promote the adoption of pit emptying, it is recommended that households be provided with information that supports pit emptying, such as latrine construction designs, local pit emptying options, and cost. This study indicates that the use of a penetrometer test in the field prior to pit latrine emptying may facilitate the selection of appropriate pit emptying technology.

  20. A Statistical Study on the Effect of Hydrostatic Pressure on Metastable Pitting Corrosion of X70 Pipeline Steel

    Directory of Open Access Journals (Sweden)

    Zixuan Yang

    2017-11-01

    Full Text Available Hydrostatic pressure effects on pitting initiation and propagation in X70 steel are investigated by evaluating metastable pitting probability using electrochemical methods and immersion corrosion tests in containing chlorine ion solution. Potentiodynamic tests indicated that hydrostatic pressure can decrease the breakdown potential and lead to a reduced transpassivity region. Metastable test results revealed that hydrostatic pressure can increase metastable pitting formation frequency and promote stabilization of metastable pitting growth. Electrochemical impedance spectroscopy (EIS results indicate that Hydrostatic pressure decreases the charge transfer resistance and increases the dissolution rate within the cavities. Corrosion test results also indicated that pitting initiation and propagation are accelerated by hydrostatic pressure. Result validity was verified by evaluating metastable pitting to predict pitting corrosion resistance.

  1. Description of work for 100-DR-2 Operable Unit Vadose Drilling/test pits

    Energy Technology Data Exchange (ETDEWEB)

    Naiknimbalkar, N.

    1993-08-01

    This report describes the scope of work for the boreholes/test pits of the 100-DR-2 Operable Unit. Sampling and field activities include: Soil screening; geologic sampling; soil sampling (physical property); analytical sampling and depths; and geophysical logging.

  2. STS-32 crewmembers use water hose during exercises at JSC fire training pit

    Science.gov (United States)

    1989-01-01

    STS-32 Commander Daniel C. Brandenstein (left) and Pilot James D. Wetherbee handle water hose during fire training exercises conducted at JSC Fire Training Pit across from the Gilruth Center Bldg 207.

  3. Remote monitoring of fish in small streams: A unified approach using PIT tags

    Science.gov (United States)

    Zydlewski, G.B.; Horton, G.; Dubreuil, T.; Letcher, B.; Casey, S.; Zydlewski, Joseph D.

    2006-01-01

    Accurate assessments of fish populations are often limited by re-observation or recapture events. Since the early 1990s, passive integrated transponders (PIT tags) have been used to understand the biology of many fish species. Until recently, PIT applications in small streams have been limited to physical recapture events. To maximize recapture probability, we constructed PIT antenna arrays in small streams to remotely detect individual fish. Experiences from two different laboratories (three case studies) allowed us to develop a unified approach to applying PIT technology for enhancing data assessments. Information on equipment, its installation, tag considerations, and array construction is provided. Theoretical and practical definitions are introduced to standardize metrics for assessing detection efficiency. We demonstrate how certain conditions (stream discharge, vibration, and ambient radio frequency noise) affect the detection efficiency and suggest that by monitoring these conditions, expectations of efficiency can be modified. We emphasize the importance of consistently estimating detection efficiency for fisheries applications.

  4. Effects of Inclusions in HSLA Carbon Steel on Pitting Corrosion in CaCl2

    Energy Technology Data Exchange (ETDEWEB)

    M. Ziomek-Moroz; S. Bullard; K. Rozman; J.J. Kruzic

    2011-12-05

    Susceptibility of high strength low alloy steel to localized corrosion was studied in 6.7 M CaCl{sub 2} for oil and natural gas drilling applications. Results of the immersion and electrochemical experiments showed that the steel is susceptible to pitting corrosion. Optical microscopy investigations of the polished samples revealed that 10% of the surface area was occupied by defects in the form of pits. The energy dispersive X-ray (EDX) and wavelength dispersive X-ray (WDX) chemical analyses revealed higher concentrations of Mn and S compared to the metal matrix in defected areas. These areas served as the sites for development of corrosion pits during both immersion and electrochemical experiments. The fatigue results of the corroded samples indicate that if the pit was the most significant defect, the fatigue crack initiated and propagated at this site.

  5. Vestured pits: a diagnostic character in the secondary xylem of Myrtales

    NARCIS (Netherlands)

    Jansen, S.; Pletsers, A.; Rabaey, D.; Lens, F.

    2008-01-01

    Vestures are small projections from the secondary cell wall associated with tracheary elements of the secondary xylem. They are usually associated with bordered pits and characterize various angiosperm families, including important timber species such as Dipterocarpaceae and Eucalyptus trees. The

  6. Software Modules for the Proximity-1 Space Link Interleaved Time Synchronization (PITS) Protocol

    Science.gov (United States)

    Woo, Simon S.; Veregge, John R.; Gao, Jay L.; Clare, Loren P.; Mills, David

    2012-01-01

    The Proximity-1 Space Link Interleaved Time Synchronization (PITS) protocol provides time distribution and synchronization services for space systems. A software prototype implementation of the PITS algorithm has been developed that also provides the test harness to evaluate the key functionalities of PITS with simulated data source and sink. PITS integrates time synchronization functionality into the link layer of the CCSDS Proximity-1 Space Link Protocol. The software prototype implements the network packet format, data structures, and transmit- and receive-timestamp function for a time server and a client. The software also simulates the transmit and receive-time stamp exchanges via UDP (User Datagram Protocol) socket between a time server and a time client, and produces relative time offsets and delay estimates.

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

    Energy Technology Data Exchange (ETDEWEB)

    HEY, B.E.

    1999-12-07

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

  8. Analysis of reactivity worth for xenon poisoning during restart-up of reactor in iodine pit

    International Nuclear Information System (INIS)

    Li Xaofeng; Chen Wenzhen; Zhu Qian; Xu Guojun

    2009-01-01

    The reactivity worth of xenon poisoning and the densities of 135 I and 135 Xe were derived when the reactor was restarted up in iodine pit. Through the expressions obtained we can find the physics characteristics of reactor restarted up in iodine pit comprehensively and essentially. The results were analyzed and discussed. The reactor power before shutdown, the start-up power, the position where the reactor starts up in iodine pit, and so on, all have effect on the reactivity worth of xenon poisoning, and the different conditions can lead to totally different physics characteristics. In addition, the time when the reactor starts up in iodine pit is a very important factor for nuclear reactors safety. The conclusions are very important to the maneuverability and operation safety of ship nuclear reactors. (authors)

  9. Description of work for 100-DR-2 Operable Unit Vadose Drilling/test pits

    International Nuclear Information System (INIS)

    Naiknimbalkar, N.

    1993-01-01

    This report describes the scope of work for the boreholes/test pits of the 100-DR-2 Operable Unit. Sampling and field activities include: Soil screening; geologic sampling; soil sampling (physical property); analytical sampling and depths; and geophysical logging

  10. PIT Tag data - Monitoring the migrations of wild Snake River spring/summer Chinook salmon juveniles

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is an ongoing Bonneville Power Administration funded project to annually collect, PIT tag, and release wild Chinook salmon parr in up to 17 streams of the...

  11. Extraction and characterization of montmorency (Prunus cerasus L.) sour cherry pit oil

    Science.gov (United States)

    Montmorency sour cherry (Prunus cerasus L.) pit oil was extracted and characterized by various methods including: gas chromatography (GC), liquid chromatography coupled with mass spectrometry (LC-MS), nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA), differential scanning calorime...

  12. Dominion Range Snow Pit and Ice Core, 1984 and 1985, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — Information from snow pits and an ice core were collected at Dominion Range (location - 166 10' East, 85 15' South, elevation - 2,700m) in 1984-1985. The 6 meter...

  13. Newall Glacier Snow Pit and Ice Core, 1987 to 1989, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — Snow pit and ice core data from the Newall Glacier (location - 162 30' East, 77 35' South) were collected during 1987 and 1988. These include information on...

  14. The fabrication and application of patterned Si(001) substrates with ordered pits via nanosphere lithography

    International Nuclear Information System (INIS)

    Chen Peixuan; Fan Yongliang; Zhong Zhenyang

    2009-01-01

    A new scalable approach has been developed for fabricating large-scale pit patterns with controllable periodicity on Si(001) substrates. The fabrication processes start with self-assembling a monolayer of polystyrene (PS) spheres on hydrogenated Si(001) substrates. A novel net-like mask in combination of the Au pattern thermally evaporated in between the PS spheres and the Au-catalyzed SiO 2 around them is naturally formed. After selective etching of Si by KOH solution, two-dimensionally ordered pits with a periodicity equal to the diameter of the PS spheres in the range from micrometers to less than 100 nm can be obtained. The shape of the pits can be modulated by controlling the chemical etching time. Such pit-patterned Si substrates facilitate the formation of ordered Si-based nanostructures, such as ordered self-assembled GeSi quantum dots, by deposition of Ge using molecular beam epitaxy.

  15. Congenital lower lip pits and bilateral clefting of the upper lip.

    Science.gov (United States)

    Chindia, M L; Kimaro, S

    1994-05-01

    An apparently sporadic case of congenital lower lip pits in association with upper lip bilateral clefts is described in an 11-month-old boy. The presentation, mode of inheritance, aetiology and genetic significance are briefly reviewed.

  16. Structure of energy consumption and improving open-pit dump truck efficiency

    Science.gov (United States)

    Koptev, V. Yu; Kopteva, A. V.

    2017-10-01

    This paper studies the dynamics of the improvement of wheel type transport vehicles environmental and energy performance in open-pit mines. The paper discloses characteristics of the gas turbine engine with capacity of 1250 hp, mounted on tanks, and technical-economic calculations, confirming reasonability of their use in open-pit dump trucks with the 120 …130-ton loading capacity. The general layout scheme of mechanical transmission with the gas turbine engine is shown.

  17. Evaluation of remote delivery of Passive Integrated Transponder (PIT technology to mark large mammals.

    Directory of Open Access Journals (Sweden)

    W David Walter

    Full Text Available Methods to individually mark and identify free-ranging wildlife without trapping and handling would be useful for a variety of research and management purposes. The use of Passive Integrated Transponder technology could be an efficient method for collecting data for mark-recapture analysis and other strategies for assessing characteristics about populations of various wildlife species. Passive Integrated Transponder tags (PIT have unique numbered frequencies and have been used to successfully mark and identify mammals. We tested for successful injection of PIT and subsequent functioning of PIT into gelatin blocks using 4 variations of a prototype dart. We then selected the prototype dart that resulted in the least depth of penetration in the gelatin block to assess the ability of PIT to be successfully implanted into muscle tissue of white-tailed deer (Odocoileus virginianus post-mortem and long-term in live, captive Rocky Mountain elk (Cervus elaphus. The prototype dart with a 12.7 mm (0.5 inch needle length and no powder charge resulted in the shallowest mean (± SD penetration depth into gelatin blocks of 27.0 mm (± 5.6 mm with 2.0 psi setting on the Dan-Inject CO(2-pressured rifle. Eighty percent of PIT were successfully injected in the muscle mass of white-tailed deer post-mortem with a mean (± SD penetration depth of 22.2 mm (± 3.8 mm; n = 6. We injected PIT successfully into 13 live, captive elk by remote delivery at about 20 m that remained functional for 7 months. We successfully demonstrated that PIT could be remotely delivered in darts into muscle mass of large mammals and remain functional for >6 months. Although further research is warranted to fully develop the technique, remote delivery of PIT technology to large mammals is possible using prototype implant darts.

  18. Pitted keratolysis – a frequently misdiagnosed, mild, infectious disorder of soles

    OpenAIRE

    Zuzanna Lewicka-Potocka; Aneta Szczerkowska-Dobosz

    2016-01-01

    Introduction . Pitted keratolysis (PK) is a mild infectious skin disorder caused by Corynebacterium spp., Kytococcus sedentarius or Dermatophilus congolensis . These bacteria produce enzymes that digest keratin, causing superficial lesions in the plantar surface. The disease is predominantly observed in young men. Objective . Pitted keratolysis despite the characteristic presentation of skin lesions is often misdiagnosed. In this article we aimed to remind readers of its clinical as...

  19. Ecological risk of reprocessing of uranium wastes of the Gafurov's tailing pit

    International Nuclear Information System (INIS)

    Khakimov, N.; Nazarov, Kh.M.; Kamalov, D.D.; Mirsaidov, U.M.

    2010-01-01

    Present article is devoted to assessment ecological risk of reprocessing of uranium wastes of the Gafurov's tailing pit. Authors set as their purpose the investigation of ecological risk of reprocessing of uranium wastes of the Gafurov-city's tailing pit. Having carried out their investigations, the authors came to the conclusion that the effect of radon gas during reprocessing to workers and specialists is minimal if they follow all the required safety rules.

  20. ANALYSIS OF THE PIT REMOVAL METHODS IN DIGITAL TERRAIN MODELS OF VARIOUS RESOLUTIONS

    OpenAIRE

    S. Šamanović; D. Medak; D. Gajski

    2016-01-01

    Digital terrain model (DTM) is the base for calculation of the surface runoff under the influence of the gravity (gravity flow) in hydrological analysis. It is important to produce hydrologically corrected DTM with the removed natural and artificial depressions to avoid numerical problems in algorithms of the gravity flow. The pit removal procedure changes geomorphometry of the DTM. GIS software packages use pit removal algorithm independently of geomorphmetric features of the analyzed area. ...

  1. Short convalescence and minimal pain after out-patient Bascom's pit-pick operation

    DEFF Research Database (Denmark)

    Colov, Emilie Palmgren; Bertelsen, Claus Anders

    2011-01-01

    Treatment of pilonidal sinuses with Bascom's pit-pick operation can easily be performed under local analgesia. We describe pain during and after the operation, time to return to work, time to healing and success rate.......Treatment of pilonidal sinuses with Bascom's pit-pick operation can easily be performed under local analgesia. We describe pain during and after the operation, time to return to work, time to healing and success rate....

  2. Designing local solutions for emptying pit latrines in low-income urban settlements (Malawi)

    Science.gov (United States)

    Chipeta, W. C.; Holm, R. H.; Kamanula, J. F.; Mtonga, W. E.; de los Reyes, F. L.

    2017-08-01

    A lack of effective options in local technology poses challenges when onsite household sanitation facilities are eventually filled to capacity in unplanned settlement areas within Mzuzu City, located in northern Malawi. Vacuum trucks currently dominate the market but focus on emptying septic tanks in the more easily accessible planned settlement areas, rather than servicing the pit latrines common in unplanned settlement areas. As a result, households in the unplanned settlement areas within Mzuzu rely primarily on manual pit emptying (i.e., shoveling by hand) or digging a new pit latrine. These practices have associated health risks and are limited by space constraints. This research focused on filling the technological gap through the design, development, and testing of a pedal powered modified Gulper pump using locally available materials and fabrication. A modified pedal powered Gulper technology was developed and demonstrated to be capable of lifting fecal sludge from a depth of 1.5 m with a mean flow rate of 0.00058 m3/s. If the trash content was low, a typical pit latrine with a volume of 1-4 m3 could be emptied within 1-2 h. Based on the findings in our research Phase IV, the pedal powered Gulper modification is promising as a potential emptying technology for lined pit latrines in unplanned settlement areas. The success rate of the technology is about 17% (5 out 30 sampled lined pit latrines were successful) and reflects the difficulty in finding a single technology that can work well in all types of pit latrines with varying contents. We note that cost should not be the only design criteria and acknowledge the challenge of handling trash in pit latrines.

  3. Enamel Pit Defects and Taurodontism in a Patient with Ring Chromosome 14 and 47,XXX.

    Science.gov (United States)

    Townsend, Janice A; Lacour, Letitia; Scheuerle, Angela E

    2017-01-15

    The purpose of this paper is to describe the clinical findings and management of a case involving a patient with co-occurring ring chromosome 14 syndrome and 47,XXX presenting with enamel pit defects and taurodontism. Ring chromosome 14 syndrome is an unusual condition with uncontrolled seizure disorder as its most significant finding; 47,XXX (trisomy X; triple X) is a more common condition and has characteristic physical and behavioral findings. Neither condition has been associated with enamel pit defects.

  4. Software development for geologic information management system on open-pit production

    Energy Technology Data Exchange (ETDEWEB)

    Li, K.; Tian, A.; Ren, Z.; Pang, Y. [China University of Mining and Technomogy, Xuzhou (China). College of Mineral and Energy Resources

    2001-09-01

    A software, including geological data gathering and processing, deposit modelling, reserves calculating and mine map plotting, for geologic information management of open-pit production was developed. Based on the interactive technique, CAD, the object-oriented simulation, and the characteristics of geologic structures, all the geologic information databases and geologic mapping sub-systems have been established for open-pit production, planning and management. 6 refs., 1 fig.

  5. Herniation pits and their renaissance in association with femoroacetabular impingement; Herniation Pits und ihre Renaissance im Zusammenhang mit femoroazetabulaerem Impingement

    Energy Technology Data Exchange (ETDEWEB)

    Panzer, Stephonie [Unfallklinik Murnau (Germany). Radiologie; Augat, P. [Unfallklinik Murnau (Germany). Radiologie; Paracelsus Univ. Salzburg (Austria). Biomechanisches Labor; Scheidler, J. [Radiologischs Zentrum Muenchen-Pasing (Germany). Radiologie

    2010-07-15

    Hernitation pits (HPs) of the femoral neck were first described in 1982. The purpose of this paper is to summarize the information concerning HPs published since then and to show their association with the diagnosis of femoroacetabular impingement (FAI) which has occurred within the last years. HPs are predominantly located at the anterior-superior femoral neck with a typical radiological appearance, which makes it possible to differentiate them from the numerous differential diagnoses mentioned. In the early publications HPs were described as a separate entity, while recent studies increasingly assign them to intra-osseous ganglia. In contrast to the early publications depicting HPs as an incidental finding, they are currently mainly mentioned in association with FAI and at the same time are partly considered to be a radiological indicator of FAI. In summary, HPs should always be recognized and documented because they may contribute to the diagnosis of FAI which is essential for preventing or delaying osteoarthritis of the hip joint in the early stage. (orig.)

  6. Pain Phenotypes and Associated Clinical Risk Factors Following Traumatic Amputation: Results from Veterans Integrated Pain Evaluation Research (VIPER).

    Science.gov (United States)

    Buchheit, Thomas; Van de Ven, Thomas; Hsia, Hung-Lun John; McDuffie, Mary; MacLeod, David B; White, William; Chamessian, Alexander; Keefe, Francis J; Buckenmaier, Chester Trip; Shaw, Andrew D

    2016-01-01

    To define clinical phenotypes of postamputation pain and identify markers of risk for the development of chronic pain. Cross-sectional study of military service members enrolled 3-18 months after traumatic amputation injury. Military Medical Center. 124 recent active duty military service members. Study subjects completed multiple pain and psychometric questionnaires to assess the qualities of phantom and residual limb pain. Medical records were reviewed to determine the presence/absence of a regional catheter near the time of injury. Subtypes of residual limb pain (somatic, neuroma, and complex regional pain syndrome) were additionally analyzed and associated with clinical risk factors. A majority of enrolled patients (64.5%) reported clinically significant pain (pain score ≥ 3 averaged over previous week). 61% experienced residual limb pain and 58% experienced phantom pain. When analysis of pain subtypes was performed in those with residual limb pain, we found evidence of a sensitized neuroma in 48.7%, somatic pain in 40.8%, and complex regional pain syndrome in 19.7% of individuals. The presence of clinically significant neuropathic residual limb pain was associated with symptoms of PTSD and depression. Neuropathic pain of any severity was associated with symptoms of all four assessed clinical risk factors: depression, PTSD, catastrophizing, and the absence of regional analgesia catheter. Most military service members in this cohort suffered both phantom and residual limb pain following amputation. Neuroma was a common cause of neuropathic pain in this group. Associated risk factors for significant neuropathic pain included PTSD and depression. PTSD, depression, catastrophizing, and the absence of a regional analgesia catheter were associated with neuropathic pain of any severity. Published by Oxford University Press on behalf of the American Academy of Pain Medicine. 2016. This work is written by US Government employees and is in the public domain in the US.

  7. Conservation Below The Species Level: Suitable Evolutionarily Significant Units Among Mountain Vipers (The Montivipera Raddei Complex) in Iran.

    Science.gov (United States)

    Behrooz, Roozbeh; Kaboli, Mohammad; Arnal, Véronique; Nazarizadeh, Masoud; Asadi, Atefeh; Salmanian, Amin; Ahmadi, Mohsen; Montgelard, Claudine

    2018-02-01

    Northern and western mountains of Iran are among the most important biodiversity and endemism hot spots for reptiles in the Middle East. Among herpetofauna, the montivipers represent an emblematic and fragmented endemic group for which estimating their level of genetic differentiation and defining conservation priorities is urgently needed. Here, we present the most comprehensive phylogenetic study on the Montivipera raddei species group comprising all five known taxa, among which three are endemic to Iran. Based on two mitochondrial genes, phylogenetic and phylogeographic analyses revealed three major lineages each presenting very contrasting distribution area. The Iranian montivipers are highly structured in clades showing low genetic diversity and corresponding to high altitude summits. Molecular dating revealed the role of Quaternary paleo-climatic oscillations and altitudinal movements of montivipers in shaping genetic diversity and differentiation of these sky-island taxa. In addition, the best scenario of historical biogeography allowed identifying three possible refugial areas in Iran most likely arising by vicariance. Based on our mitochondrial results and pending additional data, we recognize three candidate species among the Montivipera raddei complex: M. raddei, M.latifii and M. kuhrangica that are coherent with their geographical distribution. We propose that the most appropriate Evolutionary Significant Units for conservation of the montivipers are represented by thirteen units among which six are recognized as high priority. Finally, we suggest some recommendations to the IUCN as well as to the Iranian conservation policies with respect to conservation prioritization. © The American Genetic Association 2018. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  8. Near-field microwave detection of corrosion precursor pitting under thin dielectric coatings in metallic substrate

    International Nuclear Information System (INIS)

    Hughes, D.; Zoughi, R.; Austin, R.; Wood, N.; Engelbart, R.

    2003-01-01

    Detection of corrosion precursor pitting on metallic surfaces under various coatings and on bare metal is of keen interest in evaluation of aircraft fuselage. Near-field microwave nondestructive testing methods, utilizing open-ended rectangular waveguides and coaxial probes, have been used extensively for detection of surface flaws in metals, both on bare metal and under a dielectric coating. This paper presents the preliminary results of using microwave techniques to detect corrosion precursor pitting under paint and primer, applique and on bare metal. Machined pits of 500 μm diameter were detected using open-ended rectangular waveguides at V-Band under paint and primer and applique, and on bare metal. Using coaxial probes, machined pits with diameters down to 150 μm on bare metal were also detected. Relative pit size and density were shown on a corrosion-pitted sample using open-ended rectangular waveguides at frequencies of 35 GHz to 70 GHz. The use of Boeing's MAUS TM scanning systems provided improved results by alleviating standoff variation and scanning artifact. Typical results of this investigation are also presented

  9. Design-only conceptual design report for pit disassembly and conversion facility. Rev 0

    Energy Technology Data Exchange (ETDEWEB)

    Zygmunt, S.; Christensen, L.; Richardson, C.

    1997-12-12

    This design-only conceptual design report (DOCDR) was prepared to support a funding request by the Department of Energy (DOE)-Office of Fissile Material Disposition (OFMD) for engineering design of the Pit Disassembly and Conversion Facility (PDCF) Project No. 99-D-141. The PDCF will be used to disassemble the nation`s inventory of surplus nuclear weapons pits and convert the plutonium recovered from those pits into a form suitable for storage, international inspection, and final disposition. The PDCF is a complex consisting of a hardened building that will contain the plutonium processes in a safe and secure manner, and conventional buildings and structures that will house support personnel, systems, and equipment. The PDCF uses the Advanced Recovery and Integrated Extraction System (ARIES), a low waste, modular pyroprocessing system to convert pits to plutonium oxide. The PDCF project consists of engineering and design, and construction of the buildings and structures, and engineering and design, procurement, installation, testing and start-up of equipment to disassemble pits and convert plutonium in pits to oxide form. The facility is planned to operate for 10 years, averaging 3.5 metric tons (3.86 tons) of plutonium metal per year. On conclusion of operations, the PDCF will be decontaminated and decommissioned.

  10. 3D Modeling of Lacus Mortis Pit Crater with Presumed Interior Tube Structure

    Directory of Open Access Journals (Sweden)

    Ik-Seon Hong

    2015-06-01

    Full Text Available When humans explore the Moon, lunar caves will be an ideal base to provide a shelter from the hazards of radiation, meteorite impact, and extreme diurnal temperature differences. In order to ascertain the existence of caves on the Moon, it is best to visit the Moon in person. The Google Lunar X Prize(GLXP competition started recently to attempt lunar exploration missions. Ones of those groups competing, plan to land on a pit of Lacus Mortis and determine the existence of a cave inside this pit. In this pit, there is a ramp from the entrance down to the inside of the pit, which enables a rover to approach the inner region of the pit. In this study, under the assumption of the existence of a cave in this pit, a 3D model was developed based on the optical image data. Since this model simulates the actual terrain, the rendering of the model agrees well with the image data. Furthermore, the 3D printing of this model will enable more rigorous investigations and also could be used to publicize lunar exploration missions with ease.

  11. Structural Design and Monitoring Analysis of Foundation Pit Support in Yiwu Huishang Tiandi

    Science.gov (United States)

    Zhang, Chunsu

    2017-08-01

    Huishang Tiandi deep foundation pit in Yiwu is a two-story basement,which is located in the downtown area and adjacent to the city center main traffic trunk. The surrounding environment is too com-plex to slope. The excavation depth is large, the formation is weak and complex, and the groundwater level is high.In order to ensure the safety of the foundation wall and the surrounding environment, the deformation of the foundation pit support is strictly controlled, and the deformation and internal force of the foundation supporting structure and the surrounding building are monitored.The deformation law of the foundation pit is obtained through the analysis of the horizontal displacement, the deformation rate of the supporting struc-ture, the surrounding environment of the foundation pit and the internal force of the anchor cable. The relia-bility and rationality of the design of foundation pit support are verified. It is of reference value for the de-sign and construction of other deep foundation pit engineering in Yiwu area.

  12. 3D Modeling of Lacus Mortis Pit Crater with Presumed Interior Tube Structure

    Science.gov (United States)

    Hong, Ik-Seon; Yi, Yu; Yu, Jaehyung; Haruyama, Junichi

    2015-06-01

    When humans explore the Moon, lunar caves will be an ideal base to provide a shelter from the hazards of radiation, meteorite impact, and extreme diurnal temperature differences. In order to ascertain the existence of caves on the Moon, it is best to visit the Moon in person. The Google Lunar X Prize(GLXP) competition started recently to attempt lunar exploration missions. Ones of those groups competing, plan to land on a pit of Lacus Mortis and determine the existence of a cave inside this pit. In this pit, there is a ramp from the entrance down to the inside of the pit, which enables a rover to approach the inner region of the pit. In this study, under the assumption of the existence of a cave in this pit, a 3D model was developed based on the optical image data. Since this model simulates the actual terrain, the rendering of the model agrees well with the image data. Furthermore, the 3D printing of this model will enable more rigorous investigations and also could be used to publicize lunar exploration missions with ease.

  13. Electronic structures of GeSi nanoislands grown on pit-patterned Si(001) substrate

    International Nuclear Information System (INIS)

    Ye, Han; Yu, Zhongyuan

    2014-01-01

    Patterning pit on Si(001) substrate prior to Ge deposition is an important approach to achieve GeSi nanoislands with high ordering and size uniformity. In present work, the electronic structures of realistic uncapped pyramid, dome, barn and cupola nanoislands grown in (105) pits are systematically investigated by solving Schrödinger equation for heavy-hole, which resorts to inhomogeneous strain distribution and nonlinear composition-dependent band parameters. Uniform, partitioned and equilibrium composition profile (CP) in nanoisland and inverted pyramid structure are simulated separately. We demonstrate the huge impact of composition profile on localization of heavy-hole: wave function of ground state is confined near pit facets for uniform CP, at bottom of nanoisland for partitioned CP and at top of nanoisland for equilibrium CP. Moreover, such localization is gradually compromised by the size effect as pit filling ratio or pit size decreases. The results pave the fundamental guideline of designing nanoislands on pit-patterned substrates for desired applications

  14. Electronic structures of GeSi nanoislands grown on pit-patterned Si(001) substrate

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Han, E-mail: Dabombyh@aliyun.com; Yu, Zhongyuan [State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876, P.R.China (China)

    2014-11-15

    Patterning pit on Si(001) substrate prior to Ge deposition is an important approach to achieve GeSi nanoislands with high ordering and size uniformity. In present work, the electronic structures of realistic uncapped pyramid, dome, barn and cupola nanoislands grown in (105) pits are systematically investigated by solving Schrödinger equation for heavy-hole, which resorts to inhomogeneous strain distribution and nonlinear composition-dependent band parameters. Uniform, partitioned and equilibrium composition profile (CP) in nanoisland and inverted pyramid structure are simulated separately. We demonstrate the huge impact of composition profile on localization of heavy-hole: wave function of ground state is confined near pit facets for uniform CP, at bottom of nanoisland for partitioned CP and at top of nanoisland for equilibrium CP. Moreover, such localization is gradually compromised by the size effect as pit filling ratio or pit size decreases. The results pave the fundamental guideline of designing nanoislands on pit-patterned substrates for desired applications.

  15. 200 West Area Ash Pit Demolition Site closure plan. Revision 1

    International Nuclear Information System (INIS)

    Ruck, F.R.

    1994-01-01

    The Ash Pit Demolition Site had two known demolition events, the first occurred in November of 1984, and the second occurred in June of 1986. These demolition events were a form of thermal treatment for discarded explosive chemical products. Because the Ash Pit Demolition Site will no longer be used for this thermal activity, the site will be closed. Closure will be conducted pursuant to the requirements of the Washington State Department of Ecology (Ecology) ''Dangerous Waste Regulations'', Washington Administrative Code (WAC) 173-303-610 and 40 Code of Federal Regulations (CFR) 270.1. The 200 West Area Ash Pit Demolition Site Closure Plan consists of a Part A, Form 3, Dangerous Waste Permit Application (Revision 4) and a closure plan. An explanation of the Part A, Form 3, submitted with this closure plan is provided at the beginning of the Part A Section. The closure plan consists of nine chapters and five appendices. This closure plan presents a description of the Ash,Pit Demolition Site, the history of the waste treated, and the approach that will be followed to close the Ash Pit Demolition Site. Because there were no radioactively contaminated chemicals involved in the demolitions, the information on radionuclides is provided for ''information only''. Remediation of any radioactive contamination is not within the scope of this closure plan. Only dangerous constituents derived from Ash Pit Demolition Site operations will be addressed in this closure plan in accordance with WAC 173-303-610(2)(b)(i)

  16. Distributed fiber optic strain sensing to detect artificial pitting corrosion in stirrups

    Science.gov (United States)

    Zhang, Jiachen; Kancharla, Vinutha; Hoult, Neil A.

    2017-04-01

    Pitting corrosion is difficult to identify through visual inspection and can lead to sudden structural failures. As such, an experimental study was undertaken to investigate whether distributed fiber optic strain sensors are capable of detecting the locations and strain changes associated with stirrup corrosion in reinforced concrete beams. In comparison to conventional strain gauges, this type of sensor can measure the strain response along the entire length of the fiber optic cable. Two specimens were tested: a control and a deteriorated beam. The deteriorated beam was artificially corroded by reducing the cross sectional area of the closed stirrups by 50% on both sides of the stirrup at the mid-height. This level of area reduction represents severe pitting corrosion. The beams were instrumented with nylon coated fiber optic sensors to measure the distributed strains, and then tested to failure under three point bending. The load deflection behavior of the two specimens was compared to assess the impact of the artificial pitting corrosion on the capacity. Digital Image Correlation was used to locate the extent and trajectory of the crack paths. It was found that the pitting corrosion had no impact on capacity or stiffness. Also, in this investigation the fiber optic sensing system failed to detect the location and strain changes due to pitting corrosion since the shear cracks did not intersect with the pitting location.

  17. White phosphorus pits focused feasibility study final July 2007.

    Energy Technology Data Exchange (ETDEWEB)

    Davis, B.; Martino, L.

    2007-08-21

    The White Phosphorus Burning Pits (WPP) Area of Concern (AOC) is a site of about 5.5 acres (2.2 ha) located in the J-Field Study Area, in the Edgewood Area of Aberdeen Proving Ground (APG), Maryland (Figure 1.1). Considerable information about the WPP exists as a result of efforts to characterize the hazards associated with J-Field. Contamination in the J-Field Study Area was first detected during an environmental survey of the APG Edgewood Area conducted in 1977 and 1978 (Nemeth et al. 1983) by the U.S. Army Toxic and Hazardous Materials Agency (USATHAMA; predecessor to the U.S. Army Environmental Center). As part of a subsequent USATHAMA environmental survey, 11 wells were installed and sampled at J-Field (three of them at the WPP) (Nemeth 1989). Contamination was also detected in 1983 during a munitions disposal survey conducted by Princeton Aqua Science (1984). The Princeton Aqua Science investigation involved installing and sampling nine wells (four at the WPP) and collecting and analyzing surficial and deep composite soil samples (including samples from the WPP area). In 1986, the U.S. Environmental Protection Agency (EPA) issued a Resource Conservation and Recovery Act (RCRA) Permit (MD3-21-002-1355) requiring a post-wide RCRA Facility Assessment (RFA) and a hydrogeologic assessment of J-Field. In 1987, the U.S. Geological Survey (USGS) began a two-phase hydrogeologic assessment in which data were collected to model groundwater flow at J-Field. Soil-gas investigations were conducted, several well clusters were installed (four at the WPP), a groundwater flow model was developed, and groundwater and surface water monitoring programs were established that continue today. The results of the USGS study were published by Hughes (1993).

  18. Randomised controlled double-blind non-inferiority trial of two antivenoms for saw-scaled or carpet viper (Echis ocellatus envenoming in Nigeria.

    Directory of Open Access Journals (Sweden)

    Isa S Abubakar

    Full Text Available BACKGROUND: In West Africa, envenoming by saw-scaled or carpet vipers (Echis ocellatus causes great morbidity and mortality, but there is a crisis in supply of effective and affordable antivenom (ISRCTN01257358. METHODS: In a randomised, double-blind, controlled, non-inferiority trial, "EchiTAb Plus-ICP" (ET-Plus equine antivenom made by Instituto Clodomiro Picado was compared to "EchiTAb G" (ET-G ovine antivenom made by MicroPharm, which is the standard of care in Nigeria and was developed from the original EchiTAb-Fab introduced in 1998. Both are caprylic acid purified whole IgG antivenoms. ET-G is monospecific for Echis ocellatus antivenom (initial dose 1 vial and ET-Plus is polyspecific for E. ocellatus, Naja nigricollis and Bitis arietans (initial dose 3 vials. Both had been screened by pre-clinical and preliminary clinical dose-finding and safety studies. Patients who presented with incoagulable blood, indicative of systemic envenoming by E. ocellatus, were recruited in Kaltungo, north-eastern Nigeria. Those eligible and consenting were randomly allocated with equal probability to receive ET-Plus or ET-G. The primary outcome was permanent restoration of blood coagulability 6 hours after the start of treatment, assessed by a simple whole blood clotting test repeated 6, 12, 18, 24 and 48 hr after treatment. Secondary (safety outcomes were the incidences of anaphylactic, pyrogenic and late serum sickness-type antivenom reactions. FINDINGS: Initial doses permanently restored blood coagulability at 6 hours in 161/194 (83.0% of ET-Plus and 156/206 (75.7% of ET-G treated patients (Relative Risk [RR] 1.10 one-sided 95% CI lower limit 1.01; P = 0.05. ET-Plus caused early reactions on more occasions than did ET-G [50/194 (25.8% and 39/206 (18.9% respectively RR (1.36 one-sided 95% CI 1.86 upper limit; P = 0.06. These reactions were classified as severe in 21 (10.8% and 11 (5.3% of patients, respectively. CONCLUSION: At these doses, ET-Plus was

  19. Vitrectomy with or without encircling band for pseudophakic retinal detachment: a multi-centre, three-arm, randomised clinical trial. VIPER Study Report No. 1--design and enrolment.

    Science.gov (United States)

    Mazinani, B; Baumgarten, S; Schiller, P; Agostini, H; Helbig, H; Limburg, E; Hellmich, M; Walter, P

    2016-03-01

    Scleral buckling is currently used in addition to vitrectomy for the treatment of pseudophakic retinal detachment (PRD) to better support the vitreous base and better visualisation of the periphery. The aims of this study are to evaluate (1) whether the combination of 20 G vitrectomy and scleral buckling is superior to 20 G vitrectomy alone (control) (confirmatory), and (2) whether transconjunctival 23/25 G vitrectomy is non-inferior to 20 G vitrectomy (both without scleral buckling) regarding operation success (exploratory). The VIPER (Vitrectomy Plus Encircling Band Vs. Vitrectomy Alone For The Treatment Of Pseudophakic Retinal Detachment) study is an unmasked, multi-centre, three-arm randomised trial. Patients with PRD were eligible, excluding complicated retinal detachment or otherwise severe ophthalmologic impairment. Patients were randomised to one of three interventions: 20 G vitrectomy alone (control C), combination of 20 G vitrectomy and circumferential scleral buckling (experimental treatment E1) or 23/25 G vitrectomy alone (experimental treatment E2). The primary endpoint is the absence of any indication for a retina re-attaching procedure during 6 months of follow-up. Secondary endpoints include best corrected visual acuity, retina re-attaching procedures, complications and adverse events. From June 2011 to August 2013, 257 patients were enrolled in the study. The internet randomisation service assigned 100 patients each to the treatment arms C and E1, and 57 patients to treatment E2. The imbalance is due to the fact that several retinal surgeons did not qualify for performing E2. The random assignment was stratified and balanced (ie, 1:1 or 1:1:1 ratio) by surgeon. The described study represents a methodologically rigorous protocol evaluating the benefits of three different vitrectomy approaches to PRD. The projected results will help to establish their overall efficacy and will permit conclusions regarding their relative value. DRKS

  20. Pitting Corrosion Behaviour of New Corrosion-Resistant Reinforcement Bars in Chloride-Containing Concrete Pore Solution

    Science.gov (United States)

    Liu, Yao; Chu, Hong-yan; Wang, Danqian; Ma, Han; Sun, Wei

    2017-01-01

    In this study, the pitting behaviour of a new corrosion-resistant alloy steel (CR) is compared to that of low-carbon steel (LC) in a simulated concrete pore solution with a chloride concentration of 5 mol/L. The electrochemical behaviour of the bars was characterised using linear polarisation resistance (LPR) and electrochemical impedance spectroscopy (EIS). The pitting profiles were detected by reflective digital holographic microscopy (DHM), scanning electron microscopy (SEM), and the chemical components produced in the pitting process were analysed by X-ray energy dispersive spectroscopy (EDS). The results show that the CR bars have a higher resistance to pitting corrosion than the LC bars. This is primarily because of the periodic occurrence of metastable pitting during pitting development. Compared to the pitting process in the LC bars, the pitting depth grows slowly in the CR bars, which greatly reduces the risk of pitting. The possible reason for this result is that the capability of the CR bars to heal the passivation film helps to restore the metastable pits to the passivation state. PMID:28777327

  1. Pitting Corrosion Behaviour of New Corrosion-Resistant Reinforcement Bars in Chloride-Containing Concrete Pore Solution.

    Science.gov (United States)

    Jiang, Jin-Yang; Liu, Yao; Chu, Hong-Yan; Wang, Danqian; Ma, Han; Sun, Wei

    2017-08-04

    In this study, the pitting behaviour of a new corrosion-resistant alloy steel (CR) is compared to that of low-carbon steel (LC) in a simulated concrete pore solution with a chloride concentration of 5 mol/L. The electrochemical behaviour of the bars was characterised using linear polarisation resistance (LPR) and electrochemical impedance spectroscopy (EIS). The pitting profiles were detected by reflective digital holographic microscopy (DHM), scanning electron microscopy (SEM), and the chemical components produced in the pitting process were analysed by X-ray energy dispersive spectroscopy (EDS). The results show that the CR bars have a higher resistance to pitting corrosion than the LC bars. This is primarily because of the periodic occurrence of metastable pitting during pitting development. Compared to the pitting process in the LC bars, the pitting depth grows slowly in the CR bars, which greatly reduces the risk of pitting. The possible reason for this result is that the capability of the CR bars to heal the passivation film helps to restore the metastable pits to the passivation state.

  2. Characterization of pavement distress from test pit observation

    CSIR Research Space (South Africa)

    Mgangira, Martin B

    2009-08-01

    Full Text Available .J (1956). “Engineering properties of expansive clays.” Transactions, American Society of Civil Engineers, 121:641-677 Nelson, J.D and Miller, D.J. 1992. “Identification and classification of expansive FIG. 7. Crack propagation within the black cotton... for compacted clays.” Journal of the Soil Mechanics & Foundation Engineering Division, American Society of Civil Engineers. Part 1, 88 (SM3):53-87 Van der Merwe, D H (1964). “The prediction of heave from the plasticity index and the percentage clay fraction...

  3. Uranium activity ratio in water and fish from pit lakes in Kurday, Kazakhstan and Taboshar, Tajikistan

    International Nuclear Information System (INIS)

    Strømman, G.; Rosseland, B.O.; Skipperud, L.; Burkitbaev, L.M.; Uralbekov, B.; Heier, L.S.; Salbu, B.

    2013-01-01

    Kurday in Kazhakstan and Taboshar in Tajikistan were U mining sites operated during the 1950s and 1960s as part of the USSR nuclear weapon program. Today, they represent sources of potential U contamination of the environment. Within both mining sites, open pits from which U ore was extracted have been filled with water due to ground water inflow and precipitation. These artificial pit lakes contain fish consumed occasionally by the local people, and wild and domestic animals are using the water for drinking purposes. To assess the potential impact from U in these pit lakes, field work was performed in 2006 in Kurday and 2006 and 2008 in Taboshar. Results show that the U concentration in the lake waters were relatively high, about 1 mg/L in Kurday Pit Lake and about 3 mg/L in Taboshar Pit Lake. The influence of U-bearing materials on the lakes and downstream waters were investigated by measuring the U concentration and the 234 U/ 238 U activity ratios. In both Kurday and Taboshar, the ratios increased distinctively from about 1 at the pit lakes to >1.5 far downstream the lakes. The concentrations of 238 U in gill, liver, muscle and bones in fish from the pit lakes were much higher than in the reference fish. Peak concentration of U was seen in bones (13 mg/kg w.w.), kidney (9.1 mg/kg w.w.) and gills (8.9 mg/kg w.w.) from Cyprinus auratus caught in the Taboshar Pit Lake. Bioconcentration factors (BCF) calculated for organs from fish caught in the Taboshar Pit Lake, with the same tendency seen in the Kurday Pit Lake, showed that U accumulates most in bone (BCF = 4.8 L/kg w.w.), gills (BCF = 3.6 L/kg w.w.), kidney (BCF = 3.6 L/kg w.w.), and liver (BCF = 2.5 L/kg w.w.), while least was accumulated in the muscle (BCF = 0.12 L/kg w.w.)

  4. Analysis of the Potential for Use of Floating Photovoltaic Systems on Mine Pit Lakes: Case Study at the Ssangyong Open-Pit Limestone Mine in Korea

    Directory of Open Access Journals (Sweden)

    Jinyoung Song

    2016-02-01

    Full Text Available Recently, the mining industry has introduced renewable energy technologies to resolve power supply problems at mines operating in polar regions or other remote areas, and to foster substitute industries, able to benefit from abandoned sites of exhausted mines. However, little attention has been paid to the potential placement of floating photovoltaic (PV systems operated on mine pit lakes because it was assumed that the topographic characteristics of open-pit mines are unsuitable for installing any type of PV systems. This study analyzed the potential of floating PV systems on a mine pit lake in Korea to break this misconception. Using a fish-eye lens camera and digital elevation models, a shading analysis was performed to identify the area suitable for installing a floating PV system. The layout of the floating PV system was designed in consideration of the optimal tilt angle and array spacing of the PV panels. The System Advisor Model (SAM by National Renewable Energy Laboratory, USA, was used to conduct energy simulations based on weather data and the system design. The results indicated that the proposed PV system could generate 971.57 MWh/year. The economic analysis (accounting for discount rate and a 20-year operational lifetime showed that the net present value would be $897,000 USD, and a payback period of about 12.3 years. Therefore, we could know that the economic effect of the floating PV system on the mine pit lake is relatively higher than that of PV systems in the other abandoned mines in Korea. The annual reduction of greenhouse gas emissions was analyzed and found to be 471.21 tCO2/year, which is twice the reduction effect achieved by forest restoration of an abandoned mine site. The economic feasibility of a floating PV system on a pit lake of an abandoned mine was thus established, and may be considered an efficient reuse option for abandoned mines.

  5. Closure Report for Corrective Action Unit 544: Cellars, Mud Pits, and Oil Spills, Nevada National Security Site, Nevada, Revision 0

    Energy Technology Data Exchange (ETDEWEB)

    Mark Krauss and Catherine Birney

    2011-05-01

    This Closure Report (CR) presents information supporting the closure of Corrective Action Unit (CAU) 544: Cellars, Mud Pits, and Oil Spills, Nevada National Security Site, Nevada. This CR complies with the requirements of the Federal Facility Agreement and Consent Order that was agreed to by the State of Nevada; U.S. Department of Energy (DOE), Environmental Management; U.S. Department of Defense; and DOE, Legacy Management. The corrective action sites (CASs) within CAU 544 are located within Areas 2, 7, 9, 10, 12, 19, and 20 of the Nevada National Security Site. Corrective Action Unit 544 comprises the following CASs: • 02-37-08, Cellar & Mud Pit • 02-37-09, Cellar & Mud Pit • 07-09-01, Mud Pit • 09-09-46, U-9itsx20 PS #1A Mud Pit • 10-09-01, Mud Pit • 12-09-03, Mud Pit • 19-09-01, Mud Pits (2) • 19-09-03, Mud Pit • 19-09-04, Mud Pit • 19-25-01, Oil Spill • 19-99-06, Waste Spill • 20-09-01, Mud Pits (2) • 20-09-02, Mud Pit • 20-09-03, Mud Pit • 20-09-04, Mud Pits (2) • 20-09-06, Mud Pit • 20-09-07, Mud Pit • 20-09-10, Mud Pit • 20-25-04, Oil Spills • 20-25-05, Oil Spills The purpose of this CR is to provide documentation supporting the completed corrective actions and data confirming that the closure objectives for CASs within CAU 544 were met. To achieve this, the following actions were performed: • Review the current site conditions, including the concentration and extent of contamination. • Implement any corrective actions necessary to protect human health and the environment. • Properly dispose of corrective action and investigation wastes. • Document Notice of Completion and closure of CAU 544 issued by the Nevada Division of Environmental Protection.

  6. Mycotoxin occurrence on baled and pit silages collected in Co. Meath

    Directory of Open Access Journals (Sweden)

    McElhinney C.

    2015-12-01

    Full Text Available Recent studies of baled silages produced in Ireland have identified considerable filamentous fungal contamination. Many of these fungi are toxigenic, capable of producing secondary metabolites, namely mycotoxins. Mycotoxins are potentially detrimental to livestock health and some can pose a risk to consumers of animal products. Baled (n=20 and pit (n=18 silages from a sample of farms (n=38 in Co. Meath were examined to assess the occurrence of mycotoxins and ascertain whether sampling position within the pit silos (feed face vs. 3 m behind the feed face has an effect on mycotoxin content or other chemical compositional variables. Of the 20 mycotoxins assayed, baled silages contained [mean of positive values (no. of values in mean] mycotoxin concentrations (μg/kg dry matter of beauvericin 36 (2, enniatin (enn. A 9.3 (3, enn. A1 54 (8, enn. B 351 (9, enn. B1 136 (10, mycophenolic acid (MPA 11,157 (8 and roquefortine C (Roq. C 1037 (8 and pit silages contained beauvericin 25 (2 enn. A1 18 (2, enn. B 194 (9, enn. B1 57 (3, MPA 287 (6, Roq. C 3649 (6 and zearalenone 76 (1. There was no difference (P>0.05 observed in the mycotoxin concentrations between baled and pit silages, and 11 of the 20 mycotoxins assayed were below the limits of detection. The position of sampling had no effect on the mycotoxin concentration detected in pit silages. It is concluded that mycotoxin concentrations detected in these pit and baled silages in Co. Meath did not exceed EU regulation or guidance limits, and that similar chemical composition and mycotoxin concentration values occurred at the pit silage feed face and 3 m behind this feed face.

  7. The phenomenon of prehistoric ritual pits: Several examples from the central Balkans

    Directory of Open Access Journals (Sweden)

    Bulatović Aleksandar P.

    2015-01-01

    Full Text Available In recent years, the phenomenon of pits with special deposits, i.e. ritual pits, seems to have, once again, attracted attention both in Europe and in the Balkans. In the central Balkans, scientific literature related to this topic is still deficient, hence one of the objectives of this paper is to change the current state and rekindle interest in the study of this form of manifestation of the spiritual culture of prehistoric man. It appears that one of the oldest reasons for sacrificial offerings is primal, instinctive fear. The fear of the transience of life or of death compelled our ancient ancestors to make some sort of “agreement” with the surrounding forces, bestowing particular sacrifices onto them. Sacrifice represents one of the rituals of prehistoric communities which could have been performed in a number of ways and in different circumstances. One of these are offerings placed in pits, in the form of specific objects, food, drink or living beings sacrificed to higher powers and accompanied by certain symbolic actions, for the purpose of gaining their favour or help. When interpreting pits, what should further be considered is that the fundamental difference between a discarded object and an object used for a ritual purpose lies in the fact that the object of ritual character is still meaningful to man, performing a symbolic function, unlike the former, whose role is lost after being disposed of. Aritual object, an item or a living being sacrificed in a pit, is no longer of common, worldly significance (food, drink, tools, etc., but rather possesses a symbolic, sacral meaning, intended for higher powers, to propitiate and appease them, that is to create some form of the oldest religious communication. Not only is it difficult to identify the pits used for ritual purposes in the course of fieldwork, but it is even more challenging to interpret them and practically impossible to accurately reconstruct the actions performed during the

  8. A generic statistical methodology to predict the maximum pit depth of a localized corrosion process

    International Nuclear Information System (INIS)

    Jarrah, A.; Bigerelle, M.; Guillemot, G.; Najjar, D.; Iost, A.; Nianga, J.-M.

    2011-01-01

    Highlights: → We propose a methodology to predict the maximum pit depth in a corrosion process. → Generalized Lambda Distribution and the Computer Based Bootstrap Method are combined. → GLD fit a large variety of distributions both in their central and tail regions. → Minimum thickness preventing perforation can be estimated with a safety margin. → Considering its applications, this new approach can help to size industrial pieces. - Abstract: This paper outlines a new methodology to predict accurately the maximum pit depth related to a localized corrosion process. It combines two statistical methods: the Generalized Lambda Distribution (GLD), to determine a model of distribution fitting with the experimental frequency distribution of depths, and the Computer Based Bootstrap Method (CBBM), to generate simulated distributions equivalent to the experimental one. In comparison with conventionally established statistical methods that are restricted to the use of inferred distributions constrained by specific mathematical assumptions, the major advantage of the methodology presented in this paper is that both the GLD and the CBBM enable a statistical treatment of the experimental data without making any preconceived choice neither on the unknown theoretical parent underlying distribution of pit depth which characterizes the global corrosion phenomenon nor on the unknown associated theoretical extreme value distribution which characterizes the deepest pits. Considering an experimental distribution of depths of pits produced on an aluminium sample, estimations of maximum pit depth using a GLD model are compared to similar estimations based on usual Gumbel and Generalized Extreme Value (GEV) methods proposed in the corrosion engineering literature. The GLD approach is shown having smaller bias and dispersion in the estimation of the maximum pit depth than the Gumbel approach both for its realization and mean. This leads to comparing the GLD approach to the GEV one

  9. Associations between alpha angle and herniation pit on MRI revisited in 185 asympomatic hip joints

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Chae; Choi, Jung Ah [Dept. of Radiology, Seoul National University Bundang Hospital, Seongnam (Korea, Republic of)

    2015-12-15

    To evaluate the association between alpha angle and herniation pit on MRI in asymptomatic hip joints and their associations with demographic variables.Hip MRI of 185 asymptomatic hip joints of 105 adults (age 18 to 80 years) from September 2011 through December 2012 were retrospectively studied. Alpha angles were measured on oblique axial MR images by 2 observers. Herniation pit was determined by 1 observer. Size measures, prevalence, and statistical analyses were conducted regarding its association with age, gender, laterality (right or left hip). Intra- and inter-observer agreements were determined by intra-class correlation coefficient. The prevalence of herniation pit in asymptomatic hips was 21.6%. The range of alpha angle was 27.6-65.0 degrees. Seventeen and 16 out of 185 (9.1% and 8.6%) hip joints showed alpha angle of ≥ 55 degrees in first and second measurement sessions, respectively. There was no association between alpha angle ≥ 55 and presence of herniation pit. There was no association between alpha angle ≥ 55 and the size of herniation pit. Inter-observer agreement of alpha angle was 0.485 between first measurements of first vs. second observer, respectively. Intra-observer agreement of alpha angle was 0.654, respectively. Forty (21.6%) of 185 hip joints (35 of 105 patients, 33.3%) had herniation pit, with no difference according to age, gender, or laterality of hip joint. There is no association between alpha angle ≥ 55 degrees and presence of herniation pit or demographic variables.

  10. Associations between alpha angle and herniation pit on MRI revisited in 185 asympomatic hip joints

    International Nuclear Information System (INIS)

    Lee, Eun Chae; Choi, Jung Ah

    2015-01-01

    To evaluate the association between alpha angle and herniation pit on MRI in asymptomatic hip joints and their associations with demographic variables.Hip MRI of 185 asymptomatic hip joints of 105 adults (age 18 to 80 years) from September 2011 through December 2012 were retrospectively studied. Alpha angles were measured on oblique axial MR images by 2 observers. Herniation pit was determined by 1 observer. Size measures, prevalence, and statistical analyses were conducted regarding its association with age, gender, laterality (right or left hip). Intra- and inter-observer agreements were determined by intra-class correlation coefficient. The prevalence of herniation pit in asymptomatic hips was 21.6%. The range of alpha angle was 27.6-65.0 degrees. Seventeen and 16 out of 185 (9.1% and 8.6%) hip joints showed alpha angle of ≥ 55 degrees in first and second measurement sessions, respectively. There was no association between alpha angle ≥ 55 and presence of herniation pit. There was no association between alpha angle ≥ 55 and the size of herniation pit. Inter-observer agreement of alpha angle was 0.485 between first measurements of first vs. second observer, respectively. Intra-observer agreement of alpha angle was 0.654, respectively. Forty (21.6%) of 185 hip joints (35 of 105 patients, 33.3%) had herniation pit, with no difference according to age, gender, or laterality of hip joint. There is no association between alpha angle ≥ 55 degrees and presence of herniation pit or demographic variables

  11. Photoluminescence investigation of strictly ordered Ge dots grown on pit-patterned Si substrates

    International Nuclear Information System (INIS)

    Brehm, Moritz; Grydlik, Martyna; Tayagaki, Takeshi; Schmidt, Oliver G; Langer, Gregor; Schäffler, Friedrich

    2015-01-01

    We investigate the optical properties of ordered Ge quantum dots (QDs) by means of micro-photoluminescence spectroscopy (PL). These were grown on pit-patterned Si(001) substrates with a wide range of pit-periods and thus inter QD-distances (425–3400 nm). By exploiting almost arbitrary inter-QD distances achievable in this way we are able to choose the number of QDs that contribute to the PL emission in a range between 70 and less than three QDs. This well-defined system allows us to clarify, by PL-investigation, several points which are important for the understanding of the formation and optical properties of ordered QDs. We directly trace and quantify the amount of Ge transferred from the surrounding wetting layer (WL) to the QDs in the pits. Moreover, by exploiting different pit-shapes, we reveal the role of strain-induced activation energy barriers that have to be overcome for charge carriers generated outside the dots. These need to diffuse between the energy minimum of the WL in and between the pits, and the one in the QDs. In addition, we demonstrate that the WL in the pits is already severely intermixed with Si before upright QDs nucleate, which further enhances intermixing of ordered QDs as compared to QDs grown on planar substrates. Furthermore, we quantitatively determine the amount of Ge transferred by surface diffusion through the border region between planar and patterned substrate. This is important for the growth of ordered islands on patterned fields of finite size. We highlight that the Ge WL-facets in the pits act as PL emission centres, similar to upright QDs. (paper)

  12. Design approaches in quarrying and pit-mining reclamation

    Science.gov (United States)

    Arbogast, Belinda F.

    1999-01-01

    art show a celebration of beauty and experience -- abstract geology. The last design approach combines art and science in a human-nature ecosystem termed integration. With environmental concerns, an operating or reclaimed mine site can no longer be considered isolated from its surroundings. Site analysis of mine works needs to go beyond site-specific information and relate to the regional context of the greater landscape. Understanding design approach can turn undesirable features (mines and pits) into something perceived as desirable by the public.

  13. Haitian Americans.

    Science.gov (United States)

    Catanese, Anthony V.

    1998-01-01

    Uses 1990 U.S. Census data to show the changing demographic profile of Haitian Americans. Haitian Americans are likely to live along the Atlantic seaboard and to have relatively low, although not the lowest, incomes. However, the demographic mosaic of Haitian Americans is diverse, showing the effects of Haitian national and ethnic history. (SLD)

  14. Single Amino Acid Insertion in Loop 4 Confers Amphotropic Murine Leukemia Virus Receptor Function upon Murine Pit1

    DEFF Research Database (Denmark)

    Lundorf, Mikkel D.; Pedersen, Finn Skou; O'Hara, Bryan

    1998-01-01

    Pit1 is the human receptor for gibbon ape leukemia virus (GALV) and feline leukemia virus subgroup B (FeLV-B), while the related human protein Pit2 is a receptor for amphotropic murine leukemia virus (A-MuLV). The A-MuLV-related isolate 10A1 can utilize both Pit1 and Pit2 as receptors. A stretch...... of amino acids named region A was identified in Pit1 (residues 550 to 558 in loop 4) as critical for GALV and FeLV-B receptor function. We have here investigated the role of region A in A-MuLV and 10A1 entry. Insertion of a single amino acid in region A of mouse Pit1 resulted in a functional A...

  15. A Comprehensive Pitting Study of High Velocity Oxygen Fuel Inconel 625 Coating by Using Electrochemical Testing Techniques

    Science.gov (United States)

    Niaz, Akbar; Khan, Sajid Ullah

    2016-01-01

    In the present work, Inconel 625 was coated on a mild steel substrate using a high velocity oxygen fuel coating process. The pitting propensity of the coating was tested by using open circuit potential versus time, potentiodynamic polarization, electrochemical potentiokinetic reactivation, and scanning electrochemical microscopy. The pitting propensity of the coating was compared with bulk Inconel 625 alloy. The results confirmed that there were regions of different electrochemical activities on the coating which have caused pitting corrosion.

  16. Influence of microstructure and elemental partitioning on pitting corrosion resistance of duplex stainless steel welding joints

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhiqiang; Jing, Hongyang [School of Materials Science and Engineering, Tianjin University, Tianjin 300350 (China); Tianjin Key Laboratory of Advanced Joining Technology, Tianjin 300350 (China); Xu, Lianyong, E-mail: xulianyong@tju.edu.cn [School of Materials Science and Engineering, Tianjin University, Tianjin 300350 (China); Tianjin Key Laboratory of Advanced Joining Technology, Tianjin 300350 (China); Han, Yongdian; Zhao, Lei [School of Materials Science and Engineering, Tianjin University, Tianjin 300350 (China); Tianjin Key Laboratory of Advanced Joining Technology, Tianjin 300350 (China); Zhang, Jianli [Welding laboratory, Offshore Oil Engineering (Qing Dao) Company, Qing Dao 266520 (China)

    2017-02-01

    Highlights: • N{sub 2}-supplemented shielding gas promoted nitrogen solid-solution in the austenite. • Secondary austenite had higher Ni but lower Cr and Mo than primary austenite. • Pitting corrosion preferentially occurred at secondary austenite and Cr{sub 2}N. • Adding N{sub 2} in shielding gas improved pitting corrosion resistance of GTAW joint. • E2209T{sub 1} weld metal had very poor pitting corrosion resistance due to inclusions. - Abstract: The influences of microstructure and elemental partitioning on pitting corrosion resistance of duplex stainless steel joints welded by gas tungsten arc welding (GTAW) and flux-cored arc welding (FCAW) with different shielding gas compositions were studied by optical microscopy, electron backscatter diffraction, scanning electron microscopy, transmission electron microscopy, energy dispersive spectroscopy, electron probe microanalysis, and potentiostatic and potentiodynamic polarization methods The adding 2% N{sub 2} in shielding gas facilitated primary austenite formation in GTAW weld metal (WM) and suppressed Cr{sub 2}N precipitation in GTAW weld root. In the HAZ, the banded microstructure disappeared while the coarse ferrite grains maintained same orientation as the banded ferrite in the BM. In the WM, the ferrite had one single orientation throughout a grain, whereas several families of austenite appeared. The austenite both in BM and WM enriched in Ni and nitrogen, while Cr and Mo were concentrated in the ferrite and thus no element showed clear dendritic distribution in the WM (ER2209 and E2209T{sub 1}). In addition, the secondary austenite had higher Ni content but lower Cr and Mo content than the primary austenite. The N{sub 2}-supplemented shielding gas promoted nitrogen solid-solution in the primary and secondary austenite. Furthermore, the secondary austenite had relatively lower pitting resistance equivalent number (PREN) than the ferrite and primary austenite, thereby resulting in its preferential

  17. On the detection of corrosion pit interactions using two-dimensional spectral analysis

    International Nuclear Information System (INIS)

    Jarrah, Adil; Nianga, Jean-Marie; Iost, Alain; Guillemot, Gildas; Najjar, Denis

    2010-01-01

    A statistical methodology for detecting pits interactions based on a two-dimensional spectral analysis is presented. This method can be used as a tool for the exploratory analysis of spatial point patterns and can be advanced as an alternative of classical methods based on distance. One of the major advantages of the spectral analysis approach over the use of classical methods is its ability to reveal more details about the spatial structure like the scale for which pits corrosion can be considered as independent. Furthermore, directional components of pattern can be investigated. The method is validated in a first time using numerical simulations on random, regular and aggregated structures. The density of pits, used in the numerical simulations, corresponds to that assessed from a corroded aluminium sheet. In a second time, this method is applied to verify the independence of the corrosion pits observed on the aforementioned aluminium sheet before applying the Gumbel theory to determine the maximum pit depth. Indeed, the property of independence is a prerequisite of the Gumbel theory which is one of the most frequently used in the field of safety and reliability.

  18. Consequences of the instar stage for behavior in a pit-building antlion.

    Science.gov (United States)

    Alcalay, Yehonatan; Barkae, Erez David; Ovadia, Ofer; Scharf, Inon

    2014-03-01

    Pit-building antlion larvae are opportunistic predators that dig conical pits in loose soils, and prey on small arthropods that fall into their traps. We investigated different behavioral traits of second and third instar larvae selected for similar body masses, while also exploring the behavioral consistency and personalities of the third instar stage. Second instar larvae constructed smaller pits than third instar larvae. The former also responded more slowly to prey and exploited prey less efficiently. Notably, all these instar-based differences disappeared after molting into the third instar stage. In addition, third instar larvae exhibited consistent behavior in their pit size, response times to prey and to less extent in relocation distances. We detected two axes of behavior. The first axis included a correlation between pit size, response time and prey exploitation efficiency, thus reflecting investment in foraging activity. The second axis seemed to represent a trade-off between response time and relocation distance, implying that individuals that responded more slowly to prey, relocated over larger distances. These results point to coordinated behavior reflecting different levels of investment in foraging, while also emphasizing the importance of instar stage, in addition to body mass, when studying the behavior of such organisms characterized by a complex life cycle. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. A novel stepwise method to predict ultimate strength reduction in offshore structures with pitting corrosion

    Directory of Open Access Journals (Sweden)

    Sajad Rahmdel

    2015-08-01

    Full Text Available Corrosion is a factor that decreases the ultimate strength of a structure, which can lead to structural failure in an aged structure. This study proposes a reliable method to predict the ultimate strength reduction caused by pitting corrosion of a structure at various ages. Hence, the objectives of this study are as follows: (1 finding relationship between the ultimate strength reduction and pit depth and (2 finding relationship between the ultimate strength reduction and the age of structure. The presented method has six steps and was assessed by applying it to the simplified example of a thin-plate panel structure. The ultimate strengths of the panel with different pit depths were calculated using finite element analysis. The effects of material and geometric nonlinearities as well as the initial imperfections and buckling were also considered. A linear regression model, representing the relationship between the ultimate strength reduction and pit depth, was then developed. Furthermore, using the experimental data, the weighted mean value of ultimate strength reduction was acquired for different age groups of the panel. The introduced stepwise approach contemplates the nonlinearity of pitting corrosion with time by considering the experimental data. As corroborated by the successful application of the presented methodology, this method is more accurate, compared to the accepted practices available in the literature.

  20. EFFECT OF BRIDGE PIERS INCLINATION AND ROUGHNESS ON SCOUR PIT DIMENSIONS

    Directory of Open Access Journals (Sweden)

    Moaed S. Khalil

    2013-05-01

    Full Text Available In this paper a laboratory work was performed to study the effect of bridge piers inclination and surface roughness on scour pit dimensions. Fifty four experiments were conducted using three different sizes and inclinations Pier models fixed in a sandy bed channel. First, the axis of the pier was parallel to the flow, then it was inclined by 30° and finally by 45°. Each model was tested under three different flow discharges for a period not less than two hours and at the end of each experiment the dimensions of the scour pit were measured. The same experiments were repeated after roughening the surface of each pier by fine gravel of 2mm in diameter to increase its roughness.The results of the experiment showed a clear reduction in scour pit dimensions after increasing pier roughness, the percentage of decreases in scour depth was between 2 % and 61%, while the scour length decreased between 2.5% and 22%, and finally the width of scour decreases was between 3% and 19.7%. The results also showed that the inclination of pier's axis produced an increase in scour pit dimensions. Finally, the empirical relationships of the results showed that it's possible to explain the relation between the flow discharge and each of scour pit dimensions by a simple linear equation, where the determination coefficient were more than 0.94 for all relations. 

  1. Pit Latrine Emptying Behavior and Demand for Sanitation Services in Dar Es Salaam, Tanzania

    Directory of Open Access Journals (Sweden)

    Marion W. Jenkins

    2015-02-01

    Full Text Available Pit latrines are the main form of sanitation in unplanned areas in many rapidly growing developing cities. Understanding demand for pit latrine fecal sludge management (FSM services in these communities is important for designing demand-responsive sanitation services and policies to improve public health. We examine latrine emptying knowledge, attitudes, behavior, trends and rates of safe/unsafe emptying, and measure demand for a new hygienic latrine emptying service in unplanned communities in Dar Es Salaam (Dar, Tanzania, using data from a cross-sectional survey at 662 residential properties in 35 unplanned sub-wards across Dar, where 97% had pit latrines. A picture emerges of expensive and poor FSM service options for latrine owners, resulting in widespread fecal sludge exposure that is likely to increase unless addressed. Households delay emptying as long as possible, use full pits beyond what is safe, face high costs even for unhygienic emptying, and resort to unsafe practices like ‘flooding out’. We measured strong interest in and willingness to pay (WTP for the new pit emptying service at 96% of residences; 57% were WTP ≥U.S. $17 to remove ≥200 L of sludge. Emerging policy recommendations for safe FSM in unplanned urban communities in Dar and elsewhere are discussed.

  2. Use of tracers to quantify subsurface flow through a mining pit.

    Science.gov (United States)

    Schladow, S Geoffrey; Clark, Jordan F

    2008-12-01

    Three independent tracer experiments were conducted to quantify the through-flow of water from Herman Pit, an abandoned mercury (Hg) mine pit adjacent to Clear Lake, California, USA. The tracers used were Rhodamine-WT, sulfur hexafluoride, and a mixture of sulfur hexafluoride and neon-22. The tracers were injected into Herman Pit, a generally well-mixed water body of approximately 81,000 m2, and the concentrations were monitored in the mine pit, observation wells, and the lake for 2-3 months following each injection. The results for all three experiments showed that the tracer arrived at certain observation wells within days of injection. Comparing all the well data showed a highly heterogeneous response, with a small number of wells showing this near-instantaneous response and others taking months before the tracer was detectable. Tracer was also found in the lake on four occasions over a one-month period, too few to infer any pattern but sufficient to confirm the connection of the two water bodies. Using a simple mass balance model it was possible to determine the effective loss rate through advection for each of the tracers and with this to estimate the through-flow rate. The through-flow rate for all three experiments was approximately 630 L/s, at least 1-2 orders of magnitude larger than previous estimates, all of which had been based on geochemical inferences or other indirect measures of the pit through-flow.

  3. Changes in energy metabolism accompanying pitting in blueberries stored at low temperature.

    Science.gov (United States)

    Zhou, Qian; Zhang, Chunlei; Cheng, Shunchang; Wei, Baodong; Liu, Xiuying; Ji, Shujuan

    2014-12-01

    Low-temperature storage and transport of blueberries is widely practiced in commercial blueberry production. In this research, the storage life of blueberries was extended at low temperature, but fruit stored for 30 d at 0°C pitted after 2d at room-temperature. Fruit cellular structure and physiological parameters accompanying pitting in blueberries were changed. The objective of this research was to characterise properties of energy metabolism accompanying pitting in blueberries during storage, including adenosine phosphates and mitochondrial enzymes involved in stress responses. Physiological and metabolic disorders, changes in cell ultrastructure, energy content and ATPase enzyme activity were observed in pitting blueberries. Energy shortages and increased activity of phenylalanine ammonia lyase (PAL) and lipoxygenase (LOX) were observed in fruit kept at shelf life. The results suggested that sufficient available energy status and a stable enzymatic system in blueberries collectively contribute to improve chilling tolerance, thereby alleviating pitting and maintaining quality of blueberry fruit in long-term cold storage. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Effects of cold working on the pitting corrosion behavior s of AISI 304 stainless steels

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Kee Min; Kim, Jong Soo; Kim, Young Jun; Kwon, Houk Sang [KAIST, Daejon (Korea, Republic of)

    2015-12-15

    These microstructural changes by cold working can lead improvement of mechanical properties, however from a corrosion resistant point of view, the effects of cold working on the corrosion resistance of stainless steel have been argued. Several studies has been focused on the influence of cold working on the localized corrosion resistance of stainless steels. However, the opinions about the role of cold working on the localized corrosion resistance are highly in consistence. Some studies report that the pitting potential of austenitic stainless steels decreased with cold working level, on the other hands, other studies claimed that the pitting resistance was increased by cold working. Therefore it is necessary to verify how cold working affects pitting corrosion behavior of austenitic stainless steels. In the present work, the influence of cold working on the localized corrosion of AISI 304stainless steel in the neutral chloride solution was studied based on point defect model (PDM). The fraction of deformation-induced martensite was linearly increased with cold rolling level. Through cold rolling, the pitting potential was decreased, the metastable pitting event density was significantly increased and the repassivation potential was decreased. The overall localized corrosion resistance was decreased with cold working, however cold working level increased from 30 % to 50 %, localized corrosion resistance was recovered. The accumulated cation vacancy generates a void at metal/film interface, therefore film breakdown accelerates for cold worked alloys.

  5. Nano-pits on GaAs (1 0 0) surface: Preferential sputtering and diffusion

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Tanuj, E-mail: tanujkumar@cuh.ac.in [Department of Physics, Central University of Haryana, Jant-Pali, Mahendergarh 123029 (India); Panchal, Vandana [Department of Physics, National Institute of Technology, Kurukshetra 136119 (India); Kumar, Ashish; Kanjilal, D. [Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India)

    2016-07-15

    Self organized nano-structure array on the surfaces of semiconductors have potential applications in photonics, magnetic devices, photovoltaics, and surface-wetting tailoring etc. Therefore, the control over their dimensions is gaining scientific interest in last couple of decades. In this work, fabrication of pits of nano-dimensions is carried out on the GaAs (1 0 0) surface using 50 keV Ar{sup +} at normal incidence. Variation in fluence from 3 × 10{sup 17} ions/cm{sup 2} to 5 × 10{sup 18} ions/cm{sup 2} does not make a remarkable variation in the dimension of pits such as size and depth, which is confirmed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). However the simultaneous dots formation is observed along with the pits at higher fluences. Average size of pits is found to be of 22 nm with depth of 1–5 nm for the used fluences. The importance of preferential sputtering of ‘As’ as compared to ‘Ga’ is estimated using energy dispersive X-ray analysis (EDX). The observed alteration in near surface composition shows the Ga enrichment of surface, which is not being much affected by variation in fluence. The growth evolution of pits and dots for the used experimental conditions is explained on the basis of ion beam induced preferential sputtering and surface diffusion.

  6. NORM levels in Spanish pit lakes and their impact in neighboring environments

    Energy Technology Data Exchange (ETDEWEB)

    Manjon, G.; Galvan, J.A.; Mantero, J.; Diaz, I.; Garcia-Tenorio, R. [University of Seville (Spain)

    2014-07-01

    The Iberian Pyrite Belt (IPB) is a part of the South Zone of the Hercynian Iberian Massif (SW of Iberian Peninsula), being pyrite (FeS{sub 2}) the main mineral associated to this volcano-sedimentary complex. The intensive mining activities in the area, which started in the Roman Empire, have generated mine pits where underground and/or rainwater are stored. These stored waters have produced oxidation of pyrite and, consequently, the pH of pit water has become acid (pH around 2), causing the dissolution of metals and natural radionuclides. The main objective of this work is to show and discuss the levels found for different natural radionuclides (mainly uranium isotopes and daughters via α/γ spectrometry) in water samples and sediments collected from several mine pit lakes located in the south-west of Spain. The waters of the studied pit lakes can interact with the environment, and a fraction can be transferred to surrounding aquifers and even to the main river of the zone (the Odiel River). The waters of this river, when cross the mining area, show low pH values and high concentrations of U-isotopes due to acid mining drainage. Through the analysis of several isotope activity ratios, the presence of natural radionuclides in these pit lakes and its influence in the surrounding area and Odiel river will be additionally evaluated. Document available in abstract form only. (authors)

  7. Influence of chloride ions on the pitting corrosion of candidate HLW overpack materials in synthetic oxidized boom clay water

    International Nuclear Information System (INIS)

    Druyts, F.; Kursten, B.

    1999-01-01

    The corrosion behavior under repository conditions is an important issue in the selection of a container material for the deep-geological disposal of high-level nuclear waste. In considering corrosion resistant materials for the containers, attention has to be focused on localized corrosion. Therefore, cyclic potentiodynamic polarization measurements were used to investigate the pitting behavior of a number of candidate materials, including stainless steels AISI 316L, AISI 316L hMo, AISI 316Ti, higher alloyed stainless steels UNS N08904 and UNS N08926, nickel alloy UNS N96455, and titanium alloy UNS R52400. The environment considered was synthetic oxidized Boom clay water at a temperature of 90 C and with varying chloride content. UNS N96455 and UNS R52400 did not show any pitting corrosion at chloride concentrations up to 10,000 ppm. UNS N08926 was resistant to pitting at 100 and 1,000 ppm Cl - . The other alloys suffered minor or no pitting attack in the reference solution containing 100 ppm chloride, but were attacked at elevated chloride concentrations. A SEM study of the pit morphology on AISI 316L hMo and UHB 904 revealed large central pits surrounded by minor satellite pits, resulting in a rose shape. This morphology probably resulted from subsurface pit growth, where the pit was covered by a thin layer of metal

  8. A stochastic analysis of the effect of hydrostatic pressure on the pit corrosion of Fe-20Cr alloy

    International Nuclear Information System (INIS)

    Zhang Tao; Yang Yange; Shao Yawei; Meng, Guozhe; Wang, Fuhui

    2009-01-01

    The effect of hydrostatic pressure on the pit corrosion behavior of Fe-20Cr alloy was investigated in 3.5% NaCl solution by means of potentiodynamic polarization and potentiostatic technology, and the experiment data was analyzed based on stochastic theory. With the increase of hydrostatic pressure, the pit corrosion resistance of Fe-20Cr alloy was deteriorated, which was distinguished by the decrease of critical pit potential (E cirt ) and the increase of passive current density. The results also demonstrated that there exist two effects of hydrostatic pressure on the corrosion behavior of Fe-20Cr alloy: (1) the pit generation rate was evidently increased compared to that under lower hydrostatic pressure, and the metastable pits become faster and larger. However, it seemed that pit generation mechanism shows no hydrostatic pressure dependence; (2) the probability of pit growth increased with the increase of hydrostatic pressure, which implied that the metastable pit on Fe-20Cr alloy exhibited higher probability to become larger pit cavity during shorter time interval than that under lower hydrostatic pressure.

  9. Statistical study by digitalized image analysis of pitting corrosion of an AISI 304 type stainless steel in chloride environment

    International Nuclear Information System (INIS)

    Lacome, Isabelle

    1994-01-01

    This research thesis addresses the pitting corrosion of an AISI 304-type stainless steel in chloride environment, a phenomenon which is generally considered as comprising two main steps: pit initiation with local degradation of the passive film, and pit growth. By using a technique of analysis of digitalized images, the process is observed in situ and both steps are monitored. A statistical study of the initiation of all the noticed pits is performed. After a bibliographical survey on the pitting corrosion process, its mechanisms and the influence of different parameters, the author presents the studied material and the experimental methods, reports the investigation of the pitting corrosion process in potentiostatic mode over a wide range of potentials in order to study all the types of pits, discusses the influence of potential on pit initiation and growth, reports the study of the influence of hydrodynamic conditions and of ageing in solution on the different parameters, reports the analysis of passive films by photoelectron spectroscopy, and the study of the influence of an inhibitor (molybdate ions) on both steps of pitting corrosion [fr

  10. The VIMOS Public Extragalactic Redshift Survey (VIPERS). An unbiased estimate of the growth rate of structure at ⟨z⟩ = 0.85 using the clustering of luminous blue galaxies

    Science.gov (United States)

    Mohammad, F. G.; Granett, B. R.; Guzzo, L.; Bel, J.; Branchini, E.; de la Torre, S.; Moscardini, L.; Peacock, J. A.; Bolzonella, M.; Garilli, B.; Scodeggio, M.; Abbas, U.; Adami, C.; Bottini, D.; Cappi, A.; Cucciati, O.; Davidzon, I.; Franzetti, P.; Fritz, A.; Iovino, A.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; Marulli, F.; Polletta, M.; Pollo, A.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Arnouts, S.; Coupon, J.; De Lucia, G.; Ilbert, O.; Moutard, T.

    2018-02-01

    We used the VIMOS Public Extragalactic Redshift Survey (VIPERS) final data release (PDR-2) to investigate the performance of colour-selected populations of galaxies as tracers of linear large-scale motions. We empirically selected volume-limited samples of blue and red galaxies as to minimise the systematic error on the estimate of the growth rate of structure fσ8 from the anisotropy of the two-point correlation function. To this end, rather than rigidly splitting the sample into two colour classes we defined the red or blue fractional contribution of each object through a weight based on the (U - V ) colour distribution. Using mock surveys that are designed to reproduce the observed properties of VIPERS galaxies, we find the systematic error in recovering the fiducial value of fσ8 to be minimised when using a volume-limited sample of luminous blue galaxies. We modelled non-linear corrections via the Scoccimarro extension of the Kaiser model (with updated fitting formulae for the velocity power spectra), finding systematic errors on fσ8 of below 1-2%, using scales as small as 5 h-1 Mpc. We interpret this result as indicating that selection of luminous blue galaxies maximises the fraction that are central objects in their dark matter haloes; this in turn minimises the contribution to the measured ξ(rp,π) from the 1-halo term, which is dominated by non-linear motions. The gain is inferior if one uses the full magnitude-limited sample of blue objects, consistent with the presence of a significant fraction of blue, fainter satellites dominated by non-streaming, orbital velocities. We measured a value of fσ8 = 0.45 ± 0.11 over the single redshift range 0.6 ≤ z ≤ 1.0, corresponding to an effective redshift for the blue galaxies ⟨z⟩=0.85. Including in the likelihood the potential extra information contained in the blue-red galaxy cross-correlation function does not lead to an appreciable improvement in the error bars, while it increases the systematic error

  11. Pitting Initiation and Propagation of X70 Pipeline Steel Exposed to Chloride-Containing Environments

    Directory of Open Access Journals (Sweden)

    Zixuan Yang

    2017-09-01

    Full Text Available Inclusion-induced pitting initiation mechanisms in X70 steel were investigated by scanning electron microscopy, scanning Kelvin probe force microscopy (SKPFM, immersion and electrochemical polarization tests in chloride-containing ion solutions. There are three inclusion types in the X70 steel. Corrosion test results indicated that pitting corrosion resistance of type A inclusion < type C inclusion < type B inclusion, i.e., (Mn, CaS < matrix < (Al, CaO. SKPFM test results show that the type A inclusion exhibited both lower and higher potentials than the matrix, while the type B inclusion exhibited higher potential than the matrix. The corrosion test and the SKPFM potential test results are consistent. Potentiodynamic polarization results indicate that the type A and C are active inclusions, while the type B is an inactive inclusion. Three kinds of possible mechanisms of inclusion-induced pitting corrosion are established for the X70 steel.

  12. Pit-a-Pat: A Smart Electrocardiogram System for Detecting Arrhythmia.

    Science.gov (United States)

    Park, Juyoung; Lee, Kuyeon; Kang, Kyungtae

    2015-10-01

    Electrocardiogram (ECG) telemonitoring is one of the most promising applications of medical telemetry. However, previous approaches to ECG telemonitoring have largely relied on public databases of ECG results. In this article we propose a smart ECG system called Pit-a-Pat, which extracts features from ECG signals and detects arrhythmia. It is designed to run on an Android™ (Google, Mountain View, CA) device, without requiring modifications to other software. We implemented the Pit-a-Pat system using a commercial ECG device, and the experimental results demonstrate the effectiveness and accuracy of Pit-a-Pat for monitoring the ECG signal and analyzing the cardiac activity of a mobile patient. The proposed system allows monitoring of cardiac activity with automatic analysis, thereby providing a convenient, inexpensive, and ubiquitous adjunct to personal healthcare.

  13. Project W-314 241-AN-A valve pit upgrade acceptance for beneficial use

    Energy Technology Data Exchange (ETDEWEB)

    HAMMERS, J.S.

    1999-07-21

    This report identifies the responsibilities and requirements, applicable to the 241-AN-A Valve Pit Upgrades portion of Project W-314, for Acceptance for Beneficial Use in accordance with HNF-IP-0842, Vol IV, Sec 3.12. At project turnover, the end user accepts the affected Structures, Systems, and Components (SSCs) for beneficial use. This checklist is used to help the end user ensure that all documentation, training, and testing requirements are met prior to turnover. This checklist specifically identifies those items related to the upgrading of the 241-AN-A valve pit. The upgrades include: the installation of jumper/valve manifolds with position sensors, replacement pit leak detection systems, construction of replacement cover blocks, and electrical upgrades to support the instrumentation upgrades.

  14. Project W-314 241-AN-A valve pit upgrade acceptance for beneficial use

    International Nuclear Information System (INIS)

    HAMMERS, J.S.

    1999-01-01

    This report identifies the responsibilities and requirements, applicable to the 241-AN-A Valve Pit Upgrades portion of Project W-314, for Acceptance for Beneficial Use in accordance with HNF-IP-0842, Vol IV, Sec 3.12. At project turnover, the end user accepts the affected Structures, Systems, and Components (SSCs) for beneficial use. This checklist is used to help the end user ensure that all documentation, training, and testing requirements are met prior to turnover. This checklist specifically identifies those items related to the upgrading of the 241-AN-A valve pit. The upgrades include: the installation of jumper/valve manifolds with position sensors, replacement pit leak detection systems, construction of replacement cover blocks, and electrical upgrades to support the instrumentation upgrades

  15. Effects of inserted depth of wall penetration on basal stability of foundation pits

    Science.gov (United States)

    Zhou, Aizhao; Shen, Hao; Sun, Jinguo

    2017-05-01

    Evaluation of basal heave stability is one of important design checks for excavations in soft clays. The commonly used classical calculation method based on limit equilibrium theory and the safety coefficient formula recommended by the current code, do not consider the influence of supporting structure of foundation pit depth heave stability, which results in conservative. Considering the wall stiffness and strength, the effective stress changes in different depth of soil, the frictional resistance between the retaining wall and the passive zone, the vertical shear resistance of the soil behind the wall and other factors. The modified safety factor calculation formula of foundation pit stability is presented, comparison analysis of calculation method combined with examples. The calculation results show that the safety factor of foundation pit stability is improved considering the influence of supporting structure depth, the calculation results are more reasonable.

  16. The Great Bear Flare Pit Project : review of work to date

    International Nuclear Information System (INIS)

    Ridal, J.; Lean, D.; Findlay, S.C.

    1998-01-01

    Published information regarding potential toxic agents associated with flare emissions and a study to determine the risk posed to Treaty 8 First Nations (T8FN) peoples and wildlife was reviewed as part of the Great Bear Flare Pit Project (GBFPP). The project is concerned with the study of water and soil contamination in the immediate vicinity of flare pits in the Del Rio, Doig basin, Blueberry River, and Halfway River regions of T8FN lands in Alberta. The GBFPP has established good baseline data on metal contamination, and other contaminants such as benzene, toluene, ethylbenzene, xylenes (BTEX) and polycyclic aromatic hydrocarbons (PAHs) in the immediate vicinity of selected flare pits. Based on a critical assessment of reports published to date a series of prioritized recommendations for further research are made. 18 refs., 2 tabs

  17. Pitted keratolysis – a frequently misdiagnosed, mild, infectious disorder of soles

    Directory of Open Access Journals (Sweden)

    Zuzanna Lewicka-Potocka

    2016-05-01

    Full Text Available Introduction . Pitted keratolysis (PK is a mild infectious skin disorder caused by Corynebacterium spp., Kytococcus sedentarius or Dermatophilus congolensis . These bacteria produce enzymes that digest keratin, causing superficial lesions in the plantar surface. The disease is predominantly observed in young men. Objective . Pitted keratolysis despite the characteristic presentation of skin lesions is often misdiagnosed. In this article we aimed to remind readers of its clinical aspects and treatment by presenting a typical PK case. Case report. A 35-year-old man was admitted to the dermatological clinic due to skin lesions on both soles. In the physical examination we found multiple crateriform pits, associated with hyperhidrosis and malodour diagnosed as PK. Remission of lesions was observed after treatment with oral erythromycin. Conclusions . The differential diagnosis of plantar skin lesions should include PK. Due to typical clinical manifestation the diagnosis is based on physical examination.

  18. Hydrodynamic model of the open-pit mine “Buvač” (Republic of Srpska

    Directory of Open Access Journals (Sweden)

    Papić Petar

    2013-09-01

    Full Text Available Projecting of the dewatering system of the open-pit mine “Buvač” (Republic of Srpska, Bosnia and Herzegovina is based on the use of hydrodynamic model of groundwater regime. Creating the hydrodynamic model of the open-pit mine “Buvač“ was made in phases, which began by basic interpretation of collected data, along with schematization of the groundwater flow and flow conditions, and finally, forming and calibration of model. Hydrodynamic model was created as multilayer model with eight layers. Calibration of the hydrodynamic model is the starting point for making prognosis calculation in order to create the most optimal system of open-pit mine protection from groundwater. The results of model calibration indicated that the rivers Gomjenica and Bistrica, precipitation and inflow from karstified rocks are the primary sources of recharge of the limonite ore body “Buvač”.

  19. Risk assessment of occupational groups working in open pit mining: Analytic Hierarchy Process

    Directory of Open Access Journals (Sweden)

    Yaşar Kasap

    2017-01-01

    Full Text Available In open pit mining it is possible to prevent industrial accidents and the results of industrial accidents such as deaths, physical disabilities and financial loss by implementing risk analyses in advance. If the probabilities of different occupational groups encountering various hazards are determined, workers’ risk of having industrial accidents and catching occupational illnesses can be controlled. In this sense, the aim of this study was to assess the industrial accidents which occurred during open pit coal production in the Turkish Coal Enterprises (TCE Garp Lignite unit between 2005 and 2010 and to analyze the risks using the Analytic Hierarchy Process (AHP. The analyses conducted with AHP revealed that the greatest risk in open pit mining is landslides, the most risky occupational group is unskilled labourers and the most common hazards are caused by landslides and transportation/hand tools/falling.

  20. Testing of intergranular and pitting corrosion in sensitized welded joints of austenitic stainless steel

    Directory of Open Access Journals (Sweden)

    Bore V. Jegdic

    2017-06-01

    Full Text Available Pitting corrosion resistance and intergranular corrosion of the austenitic stainless steel X5Cr Ni18-10 were tested on the base metal, heat affected zone and weld metal. Testing of pitting corrosion was performed by the potentiodynamic polarization method, while testing of intergranular corrosion was performed by the method of electrochemical potentiokinetic reactivation with double loop. The base metal was completely resistant to intergranular corrosion, while the heat affected zone showed a slight susceptibility to intergranular corrosion. Indicators of pitting corrosion resistance for the weld metal and the base metal were very similar, but their values are significantly higher than the values for the heat affected zone. This was caused by reduction of the chromium concentration in the grain boundary areas in the heat affected zone, even though the carbon content in the examined stainless steel is low (0.04 wt. % C.

  1. Surplus weapons plutonium: Technologies for pit disassembly/conversion and MOX fuel fabrication

    International Nuclear Information System (INIS)

    Toevs, J.W.

    1997-01-01

    This paper will provide a description of the technologies involved in the disposition of plutonium from surplus nuclear weapon components (pits), based on pit disassembly and conversion and on fabrication of mixed oxide (MOX) fuel for disposition through irradiation in nuclear reactors. The MOX/Reactor option is the baseline disposition plan for both the US and russian for plutonium from pits and other clean plutonium metal and oxide. In the US, impure plutonium in various forms will be converted to oxide and immobilized in glass or ceramic, surrounded by vitrified high level waste to provide a radiation barrier. A similar fate is expected for impure material in Russia as well. The immobilization technologies will not be discussed. Following technical descriptions, a discussion of options for monitoring the plutonium during these processes will be provided

  2. Alternatives Analysis Amchitka Island Mud Pit Cap Repair, Amchitka, Alaska January 2016

    Energy Technology Data Exchange (ETDEWEB)

    Darr, Paul S. [US Department of Energy, Washington, DC (United States). Office of Legacy Management

    2016-01-01

    The U.S. Department of Energy (DOE) Office of Legacy Management (LM) manages the Nevada Offsites program, which includes a series of reclaimed drilling mud impoundments on Amchitka Island, Alaska (Figure 1). Navarro Research and Engineering, Inc. is the Legacy Management Support contractor (the Contractor) for LM. The Contractor has procured Tetra Tech, Inc. to provide engineering support to the Amchitka mud pit reclamation project. The mud pit caps were damaged during a 7.9-magnitude earthquake that occurred in 2014. The goals of the current project are to investigate conditions at the mud pit impoundments, identify feasible alternatives for repair of the cover systems and the contents, and estimate relative costs of repair alternatives. This report presents descriptions of the sites and past investigations, existing conditions, summaries of various repair/mitigation alternatives, and direct, unburdened, order-of-magnitude (-15% to +50%) associated costs.

  3. Does a Progressive PIT Stabilize the Economy? A Comparison of Progressive and Flat Taxes

    Directory of Open Access Journals (Sweden)

    Krajewski Piotr

    2017-03-01

    Full Text Available The aim of the article is to examine the impact of progressive personal income tax rates and the effectiveness of this tax as an automatic economic stabilizer. The assessment of automatic stabilizers is based on the estimates of tax cyclical components. The study shows that the output elasticity of PIT is higher than one, which means that the analysed tax acts relatively efficiently as an automatic stabilizer. However, it was also observed that the tax progressivity is not the main reason of the effectiveness of a progressive PIT as an automatic stabilizer. The study shows that changes in progressive rates of PIT, contrary to widespread opinions, have little effect on the effectiveness of passive fiscal policy. Personal income tax acts as automatic stabilizer mostly due not to the progressive tax rates, but because of the sensitivity of employment to GDP fluctuations.

  4. Partial pit exhaust improves indoor air quality and effectiveness of air cleaning in livestock housing

    DEFF Research Database (Denmark)

    Zhang, Guoqiang; Bjerg, B.; Zong, C.

    2017-01-01

    approach to reduce emissions by combining an effective exhaust cleaner. The system can significantly improve the indoor air quality, because a considerable amount of the concentrated pollutants in the air are removed directly via PPAE. The pollutant removal via PPAE is influenced by airflow patterns......Ammonia and odor emissions from livestock production systems cause negative impact on atmospheric environment and local society. It is, therefore, important to develop cost-effective methods to reduce these emissions. Air cleaning technologies, including chemical and biological filters, have been...... and optimal indoor air quality of confined farm animal buildings, a concept of partial pit ventilation has been investigated in varied conditions in Denmark. Partial pit ventilation is based on the hypothesis that the most polluted air can be removed by a separate air exhaust near the pollution sources in pit...

  5. INFLUENCE OF AISI 316Ti STAINLESS STELL SURFACE TREATMENT ON PITTING CORROSION IN VARIOUS SOLUTIONS

    Directory of Open Access Journals (Sweden)

    Pavol Fajnor

    2010-12-01

    Full Text Available Investigation of the surface treatment effect on the resistance of AISI 316Ti stainless steel to pitting corrosion is presented in this paper. The grinded surfaces without additional chemical treatment, grinded and pickled, grinded, pickled and passivated surfaces are tested. The corrosion tests are carried out by exposition in solution which evoke pitting and by electrochemical cyclic potential - sweep method. According to the results the surface treatment has a great influence on the resistance of the tested material to pitting. It is not possible to estimate the best surface treatment because behavior of AISI 316Ti stainless steel with different surface state depends on the mechanism of corrosion processes which vary in the used experimental methods.

  6. Primitive environment control for preservation of pit relics in archeology museums of China.

    Science.gov (United States)

    Gu, Zhaolin; Luo, Xilian; Meng, Xiangzhao; Wang, Zanshe; Ma, Tao; Yu, Chuck; Rong, Bo; Li, Ku; Li, Wenwu; Tan, Ying

    2013-02-05

    Immovable historical relics in some archeology museums of China suffer deterioration due to their improper preservation environment. The existing environmental control systems used in archeology museums are often designed for the amenities of visitors, and these manipulated environments are often inappropriate for the conservation of abiotic relics. This paper points out that the large open space of the existing archeology museum could be a cause of deterioration of the relics from the point of view of indoor air convective flow. The paper illustrates the need to introduce a local pit environmental control, which could reintegrate a pit primitive environment for the preservation of the historical relics by using an air curtain system, orientated to isolate the unearthed relics, semiexposed in pits to the large gallery open space of the exhibition hall.

  7. Study on the application of permeable reactive barriers for remediation of uranium mine pit water

    International Nuclear Information System (INIS)

    Li Na'na; Zhu Yucheng

    2012-01-01

    Permeable reactive barrier (PRB) is economical and convenient on in suit remediation of polluted groundwater. In this paper, according to characteristics of uranium mine pit water, laboratory-scale PRB reactors were designed with the mixture of valent iron, active carbon, hydrated lime and quartz sands as reaction media. The feasibility and effectiveness of treating uranium mine pit water by PRB were tested under 3 different proportions of contaminants through dynamic simulation tests, which came out the optimal proportion of contaminants. The result indicated that the remediation effect of reactor B was the best, whose average removal rate to U was up to 99%. The quality of effluent attained the relevant standards, which indicated that the PRB technology is a feasible method for the treatment of uranium mine pit water. (authors)

  8. Prediction of the net radon emission from a model open pit uranium mine

    International Nuclear Information System (INIS)

    Nielson, K.K.; Perkins, R.W.; Schwendiman, L.C.; Enderlin, W.I.

    1979-09-01

    Radon emission from a model open pit uranium mining operation has been estimated by applying radon exhalation fluxes measured in an open pit uranium mine to the various areas of the model mine. The model mine was defined by averaging uranium concentrations, mine dimensions, production and procedural statistics for eight major open pit uranium mines in the Casper, Wyoming area. The resulting emission rates were 630 Ci/RRY (1 RRY one = 1000-MW(e) reactor operating for 1 year) during mining operations and 26 Ci/RRY/y after abandoment of the mine assuming 100% recovery of U 3 O 8 from the ore, or 700 Ci/RRY and 29 Ci/RRY/y assuming 90.5% recovery

  9. Effects of heat input on pitting corrosion in super duplex stainless steel weld metals

    Science.gov (United States)

    Shin, Yong taek; Shin, Hak soo; Lee, Hae woo

    2012-12-01

    Due to the difference in reheating effects depending on the heat input of subsequent weld passes, the microstructure of the weld metal varies between acicular type austenite and a mixture of polygonal type and grain boundary mixed austenite. These microstructural changes may affect the corrosion properties of duplex stainless steel welds. This result indicates that the pitting resistance of the weld can be strongly influenced by the morphology of the secondary austenite phase. In particular, the ferrite phase adjacent to the acicular type austenite phase shows a lower Pitting Resistance Equivalent (PRE) value of 25.3, due to its lower chromium and molybdenum contents, whereas the secondary austenite phase maintains a higher PRE value of more than 38. Therefore, it can be inferred that the pitting corrosion is mainly due to the formation of ferrite phase with a much lower PRE value.

  10. Effects of heat input on the pitting resistance of Inconel 625 welds by overlay welding

    Science.gov (United States)

    Kim, Jun Seok; Park, Young IL; Lee, Hae Woo

    2015-03-01

    The objective of this study was to establish the relationship between the dilution ratio of the weld zone and pitting resistance depending on the heat input to welding of the Inconel alloy. Each specimen was produced by electroslag welding using Inconel 625 as the filler metal. In the weld zone of each specimen, dendrite grains were observed near the fusion line and equiaxed grains were observed on the surface. It was also observed that a melted zone with a high Fe content was formed around the fusion line, which became wider as the welding heat input increased. In order to evaluate the pitting resistance, potentiodynamic polarization tests and CPT tests were conducted. The results of these tests confirmed that there is no difference between the pitting resistances of each specimen, as the structures of the surfaces were identical despite the effect of the differences in the welding heat input for each specimen and the minor dilution effect on the surface.

  11. PitPro 1.1 User's Manual; Pit-tag to SURPH Data Translation Utility, Technical Manual 2003.

    Energy Technology Data Exchange (ETDEWEB)

    Westhagen, Peter; Skalski, John

    2003-07-01

    This manual describes the use of Program PitPro to convert PIT-tag data files in PTAGIS (PIT Tag Information System, Pacific States Marine Fisheries Commission) to input files ready for survival analysis in Program SURPH 2.1. This utility converts the various PIT-tag detections at the multitude of detector coils within a juvenile bypass or at adult counting windows and ladders into capture histories. The capture histories indicate whether a tagged fish was detected, not detected, or detected and censored at the major hydroprojects in the Columbia Basin. A major update to this program is the inclusion of adult upstream detection histories. Adult detection histories include not only whether the fish was detected or not but also the year of detection for proper adult survival estimation. The SURPH program is a valuable tool for estimating survival and detection probabilities of fish migrating in the Snake and Columbia rivers. Using special input data files, SURPH computes reach-to-reach statistics for any release group passing a system of detection sites. However, PIT-tag data, as available from PTAGIS, comes in a form that is not ready for use as SURPH input. SURPH requires a capture history for each fish. A capture history consists of a series of fields, one for each detection site, that has a code for whether the fish was detected and returned to the river, detected and removed, or not detected. The data, as received from PTAGIS, has one line for each detection with information such as fish identification (id), detection date and time, number of coil hits and detector coil ids, etc. Because an individual fish may be detected at several coils within a detection site as well as at several detection sites, each fish is often represented by multiple lines in the PTAGIS data file. For the PTAGIS data to be usable by SURPH, it must be preprocessed. The data must be condensed down to one line per fish with the relevant detection information from the PTAGIS file

  12. SVET, AFM and AES study of pitting corrosion initiated on MnS inclusions by microinjection

    International Nuclear Information System (INIS)

    Vuillemin, B.; Philippe, X.; Oltra, R.; Vignal, V.; Coudreuse, L.; Dufour, L.C.; Finot, E.

    2003-01-01

    As pitting is a random phenomenon, it is difficult to predict where a pit will appear on the surface and consequently the use of local probes is rendered difficult. In this work, a new method to study pitting corrosion on a MnS inclusion on 316L stainless steel is proposed. It consists in modifying locally the chemistry in its vicinity by injecting with a microcapillary an aggressive solution of NaCl, H 2 SO 4 or HCl. Once a pit appears, scanning vibrating electrode technique (SVET) is used to follow the current fluctuations over and around the pit when the metal is polarized at a passive potential. In another series of experiments the effect of local activation of MnS inclusion was studied ex-situ using Auger electron spectroscopy (AES) and atomic force microscopy. It is observed that a single pit can be initiated only when hydrochloric acid is injected, whereas sulphuric acid only partially dissolved the inclusion. On another hand, the surface morphology is not affected when a sodium chloride solution is injected. A significant enrichment in sulphur is detected around the inclusion by AES, and micropits are observed in the metal at the edge of the inclusion after HCl activation. Anodic zones are detected by SVET around the inclusion, whereas a cathodic current flows from the inclusion. The anodic current is clearly ascribed to the breakdown of passivity induced by adsorbed sulphur coming from the MnS dissolution, whereas various assumptions can be proposed for the origin of the cathodic current

  13. Influence of sulphur and molybdenum on pitting corrosion of stainless steel in chloride solutions

    International Nuclear Information System (INIS)

    Brennert, S.

    1979-01-01

    When a stainless steel corrodes in a neutral chloride solution with the formation of pits, the anode solution in the pits has a low pH value, is rich in chlorides and contains some H 2 S, formed when the sulphide inclusions dissolve in the acid anode solution. The aim of the research work has been to study how the anode reaction is influenced firstly by the H 2 S content of the anode solution and secondly by the S content and the Mo content of the steel. In the first part of the investigation an active surface of a stainless steel type 18-8 was polarized in acid chloride solutions with different pH values and different H 2 S contents up to 100 ppm at increasing potentials. The result was that hydrogen ions and H 2 S widened the active region in the polarization curve in all directions. In the second part of the investigation active surfaces of austenitic steels with different S and Mo contents were polarized in an acid chloride solution at increasing potentials. The result was that S in the steel widened and Mo contracted the active region in the polarization curve in all directions. Applied to pits, developing under conditions in practice, the results indicate that sulphur increases and molybdenum reduces the potential difference in the corrosion cell but the effect is not very great and the corrosion rate is changed only moderately. The essential influence of the two components is supposed to be that sulphur will counteract and molybdenum will facilitate the passivation of the active surface in a pit. This will influence both the moment when a pit will start to grow and the moment when it will stop. Thus on average the life of a pit in a steel will be extended with increasing sulphur content and shortened with increasing molybdenum content. (author)

  14. Understanding the Chronology and Occupation Dynamics of Oversized Pit Houses in the Southern Brazilian Highlands

    Science.gov (United States)

    Gregorio de Souza, Jonas; Robinson, Mark; Corteletti, Rafael; Cárdenas, Macarena Lucia; Wolf, Sidnei; Iriarte, José; Mayle, Francis; DeBlasis, Paulo

    2016-01-01

    A long held view about the occupation of southern proto-Jê pit house villages of the southern Brazilian highlands is that these sites represent cycles of long-term abandonment and reoccupation. However, this assumption is based on an insufficient number of radiocarbon dates for individual pit houses. To address this problem, we conducted a programme of comprehensive AMS radiocarbon dating and Bayesian modelling at the deeply stratified oversized pit House 1, Baggio I site (Cal. A.D. 1395–1650), Campo Belo do Sul, Santa Catarina state, Brazil. The stratigraphy of House 1 revealed an unparalleled sequence of twelve well preserved floors evidencing a major change in occupation dynamics including five completely burnt collapsed roofs. The results of the radiocarbon dating allowed us to understand for the first time the occupation dynamics of an oversized pit house in the southern Brazilian highlands. The Bayesian model demonstrates that House 1 was occupied for over two centuries with no evidence of major periods of abandonment, calling into question previous models of long-term abandonment. In addition, the House 1 sequence allowed us to tie transformations in ceramic style and lithic technology to an absolute chronology. Finally, we can provide new evidence that the emergence of oversized domestic structures is a relatively recent phenomenon among the southern proto-Jê. As monumental pit houses start to be built, small pit houses continue to be inhabited, evidencing emerging disparities in domestic architecture after AD 1000. Our research shows the importance of programmes of intensive dating of individual structures to understand occupation dynamics and site permanence, and challenges long held assumptions that the southern Brazilian highlands were home to marginal cultures in the context of lowland South America. PMID:27384341

  15. Upper Extremity Injuries in NASCAR Drivers and Pit Crew: An Epidemiological Study.

    Science.gov (United States)

    Wertman, Gary; Gaston, R Glenn; Heisel, William

    2016-02-01

    Understanding the position-specific musculoskeletal forces placed on the body of athletes facilitates treatment, prevention, and return-to-play decisions. While position-specific injuries are well documented in most major sports, little is known about the epidemiology of position-specific injuries in National Association for Stock Car Automobile Racing (NASCAR) drivers and pit crew. To investigate position-specific upper extremity injuries in NASCAR drivers and pit crew members. Descriptive epidemiological study. A retrospective chart review was performed to assess position-specific injuries in NASCAR drivers and pit crew members. Included in the study were patients seen by a single institution between July 2003 and October 2014 with upper extremity injuries from race-related NASCAR events or practices. Charts were reviewed to identify the diagnosis, mechanism of injury, and position of each patient. A total of 226 NASCAR team members were treated between July 2003 and October 2014. Of these, 118 injuries (52%) occurred during NASCAR racing events or practices. The majority of these injuries occurred in NASCAR changers (42%), followed by injuries in drivers (16%), carriers (14%), jack men (11%), fuel men (9%), and utility men (8%). The majority of the pit crew positions are at risk for epicondylitis, while drivers are most likely to experience neuropathies, such as hand-arm vibration syndrome. The changer sustains the most hand-related injuries (42%) on the pit crew team, while carriers commonly sustain injuries to their digits (29%). Orthopaedic injuries in NASCAR vary between positions. Injuries in NASCAR drivers and pit crew members are a consequence of the distinctive forces associated with each position throughout the course of the racing season. Understanding these forces and position-associated injuries is important for preventive measures and facilitates diagnosis and return-to-play decisions so that each team can function at its maximal efficiency.

  16. Robustness of xylem properties in conifers: analyses of tracheid and pit dimensions along elevational transects.

    Science.gov (United States)

    Losso, Adriano; Anfodillo, Tommaso; Ganthaler, Andrea; Kofler, Werner; Markl, Yvonne; Nardini, Andrea; Oberhuber, Walter; Purin, Gerhard; Mayr, Stefan

    2018-02-01

    In alpine regions, tree hydraulics are limited by low temperatures that restrict xylem growth and induce winter frost drought and freezing stress. While several studies have dealt with functional limitations, data on elevational changes in functionally relevant xylem anatomical parameters are still scarce. In wood cores of Pinus cembra L. and Picea abies (L.) Karst. trunks, harvested along five elevational transects, xylem anatomical parameters (tracheid hydraulic diameter dh, wall reinforcement (t/b)2), pit dimensions (pit aperture Da, pit membrane Dm and torus Dt diameters) and respective functional indices (torus overlap O, margo flexibility) were measured. In both species, tracheid diameters decreased and (t/b)2 increased with increasing elevation, while pit dimensions and functional indices remained rather constant (P. cembra: Dt 10.3 ± 0.2 μm, O 0.477 ± 0.005; P. abies: Dt 9.30 ± 0.18 μm, O 0.492 ± 0.005). However, dh increased with tree height following a power trajectory with an exponent of 0.21, and also pit dimensions increased with tree height (exponents: Dm 0.18; Dt 0.14; Da 0.11). Observed elevational trends in xylem structures were predominantly determined by changes in tree size. Tree height-related changes in anatomical traits showed a remarkable robustness, regardless of the distributional ranges of study species. Despite increasing stress intensities towards the timberline, no adjustment in hydraulic safety at the pit level was observed. © The Author(s) 2018. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. Remitting seronegative symmetrical synovitis with pitting edema (RS3PE syndrome

    Directory of Open Access Journals (Sweden)

    Neslihan Gokcen

    2017-03-01

    Full Text Available Remitting seronegative symmetrical synovitis with pitting edema is a rare rheumatological disorder that presents with symmetrical hand and/or foot edema resembling rheumatoid arthritis. It is generally seen in male patients in older age, but atypical cases in different age groups have been documented. Although no clear mechanism has been described, certain genetic and environmental factors have been suggested for etiopathogenesis. Medical treatment is mainly focused on glucocorticoid therapy. This article aims to discuss the Remitting seronegative symmetrical synovitis with pitting edema syndrome and to review the current literature. [Cukurova Med J 2017; 42(1.000: 147-154

  18. Project W-314 specific test and evaluation plan for 241-AY-01A pump pit upgrade

    International Nuclear Information System (INIS)

    Hays, W.H.

    1998-01-01

    This Specific Test and Evaluation Plan (STEP) defines the test and evaluation activities encompassing the upgrade of the 241-AY-0IA Pump Pit for the W-314 Project. The purpose of this Specific Test and Evaluation Plan (STEP) is to provide a detailed written plan for the systematic testing of modifications made to the 241-AY-01A Pump Pit by the W-314 Project. The STEP develops the outline for test procedures that verify the system's performance to the established Project design criteria. The STEP is a lower tier document based on the W-314 Test and Evaluation Plan (TEP)

  19. Efficient utilization of waste date pits for the synthesis of green diesel and jet fuel fractions

    International Nuclear Information System (INIS)

    Al-Muhtaseb, Ala’a H.; Jamil, Farrukh; Al-Haj, Lamya; Al-Hinai, Mohab A.; Baawain, Mahad; Myint, Myo Tay Zar; Rooney, David

    2016-01-01

    Highlights: • Active catalysts Pt/C and Pd/C were developed from waste date pits. • Catalysts showed good activity in hydrodeoxygenation of date pit oil to alkane fuels. • The liquid product fractions lay within the range of the jet fuel and green diesel. • Green diesel fraction obtained by Pd/C was 72.03% and jet fuel was 30.39%. • Date pits can be a promising platform for the production of catalysts and biofuels. - Abstract: Date pits are considered one of the major agricultural wastes in Oman. The present work involves the synthesis of active catalysts from waste date pits carbon produced by carbonization and impregnation with Pt and Pd metals. Synthesized catalysts Pt/C and Pd/C were characterized by XRD, SEM, TEM, EDX, BET and XPS. The activity of the catalysts’ performance was evaluated by the hydrodeoxygenation of date pits oil for the production of second-generation biofuels, which includes jet fuel and green diesel fractions. Results indicate that the synthesized catalysts were highly active for the hydrodeoxygenation of date pits oil. Based on the elemental analysis, the degree of deoxygenation (DOD) of product oil was 97.5% and 89.4% for the Pd/C and Pt/C catalysts respectively. The high DOD was also confirmed by product analyses that mainly consist of paraffinic hydrocarbons. Results also showed that between the two catalysts, Pd/C showed a higher activity towards hydrodeoxygenation, a conclusion that was based on the high DOD of the product oil due to hydrocarbons formation. Based on the type of components in the product oil, the maximum fraction of hydrocarbons formed lay within the range of 72.03% and 72.78% green diesel, and 30.39% and 28.25% jet fuel using Pd/C and Pt/C catalysts respectively. It can be concluded that waste date pits can be a promising platform for the production of catalysts and biofuels.

  20. Pitting corrosion of friction stir welded aluminum alloy thick plate in alkaline chloride solution

    International Nuclear Information System (INIS)

    Xu Weifeng; Liu Jinhe; Zhu Hongqiang

    2010-01-01

    The pitting corrosion of different positions (Top, Middle and Bottom) of weld nugget zone (WNZ) along thickness plate in friction stir welded 2219-O aluminum alloy in alkaline chloride solution was investigated by using open circuit potential, cyclic polarization, scanning electron microscopy and atomic force microscope. The results indicate that the material presents significant passivation, the top has highest corrosion potential, pitting potential and re-passivation potential compared with the bottom and base material. With the increase of traverse speed from 60 to 100 mm/min or rotary speed from 500 to 600 rpm, the corrosion resistance decreases.

  1. PITTING CORROSION OF AISI 316Ti STAINLESS STEEL WITH POLISHED SURFACE

    Directory of Open Access Journals (Sweden)

    Viera Zatkalíková

    2010-05-01

    Full Text Available AISI 316Ti is Cr–Ni–Mo austenitic stainless steel with the high Pitting Resistance Equivalent Number (PREN. The effect of the surface finishing by polishing on the pitting corrosion resistance was tested in aggressive 5% FeCl3 solution. The immersion tests were curried out at the temperature 30, 50, 80 °C. The electrochemical cyclic potentiodynamic tests were carried out in the same solution at temperature 30 and 50 °C. The evaluation of the corrosion resistance arose from the comparison of the results of the immersion and the cyclic potentiodynamic tests.

  2. An assessment of a partial pit ventilation system to reduce emission under slatted floor

    DEFF Research Database (Denmark)

    Wu, Wentao; Zhang, Guoqiang; Bjerg, Bjarne Schmidt

    2012-01-01

    of measured and calculated removal ratios were found for most of cases. It was feasible to use RSM to predict the removal capability. The future research should focus on depicting the airflow patterns inside the pit by using scale model under well controlled laboratory conditions and generating benchmark data...... to validate and improve CFD methods. Unsteady CFD simulation using large eddy simulation could be conducted to make more precise predictions of removal capability of the partial pit ventilation system by considering the unsteady phenomena of gas emission....

  3. Project W-314 specific test and evaluation plan for 241-AY-02A pump pit upgrade

    International Nuclear Information System (INIS)

    Hays, W.H.

    1998-01-01

    This Specific Test and Evaluation Plan (STEP) defines the test and evaluation activities encompassing the upgrade of the 241-AY-02A Pump Pit for the W-314 Project. The purpose of this Specific Test and Evaluation Plan (STEP) is to provide a detailed written plan for the systematic testing of modifications made to the 241-AY-02A Pump Pit by the W-314 Project. The STEP develops the outline for test procedures that verify the system's performance to the established Project design criteria. The STEP is a lower tier document based on the W-314 Test and Evaluation Plan (TEP)

  4. Posthandling survival and PIT tag retention by alewives—a comparison of gastric and surgical implants

    Science.gov (United States)

    Castro-Santos, Theodore; Voni, Volney

    2013-01-01

    We compared survival and tag retention of Alewives Alosa pseudoharengus tagged with PIT tags, using intraperitoneal (IP) surgical implants, gastric implants (GI), and untagged controls held for 38 d. Retention was 100% for IP-tagged Alewives and 98% for GI-tagged implants. No significant difference in survival was observed among any of these groups. These results lend support to the use of PIT telemetry for studying fish passage and migration of anadromous herring. Both methods hold promise for improving estimates of freshwater survival of adult anadromous clupeids; further research should make it also possible to refine estimates of adult marine survival.

  5. The effect of magnetic field on the shape of etch pits of paracetamol crystals

    Energy Technology Data Exchange (ETDEWEB)

    Ivashchenko, V.E. [Kemerovo State University, Novosibirsk (Russian Federation); Research and Educational Center, Novosibirsk State University (Russian Federation); Boldyrev, V.V.; Shakhtshneider, T.P. [Institute of Solid State Chemistry and Mechanochemistry, RAS, Novosibirsk (Russian Federation); Zakharov, Yu.A.; Krasheninin, V.I. [Kemerovo State University, Novosibirsk (Russian Federation); Ermakov, A.E. [Institute of Physics of Metals, Ural Branch of RAS, Ekaterinburg (Russian Federation)

    2002-04-01

    In the present study we investigate the effect of magnetic field on the shape of etch pits of the crystals of p-hydroxyacetanilide (paracetamol), which is widely used in pharmacy as antipyretic, antiphlogistic medicine. It was discovered that the magnetic field (H=0.5 T, {tau}=15 min) changes the morphology of etch pits and shifts dislocations in paracetamol crystal. Activation energy of the changes induced by the action of the magnetic field was determined to be 63 kJ/mol, which is comparable with the energy of hydrogen bonds in crystal lattice. (orig.)

  6. American = Independent?

    Science.gov (United States)

    Markus, Hazel Rose

    2017-09-01

    U.S. American cultures and psyches reflect and promote independence. Devos and Banaji (2005) asked, does American equal White? This article asks, does American equal independent? The answer is that when compared to people in East Asian or South Asian contexts, people in American contexts tend to show an independent psychological signature-a sense of self as individual, separate, influencing others and the world, free from influence, and equal to, if not better than, others (Markus & Conner, 2013). Independence is a reasonable description of the selves of people in the White, middle-class American mainstream. Yet it is a less good characterization of the selves of the majority of Americans who are working-class and/or people of color. A cultural psychological approach reveals that much of North American psychology is still grounded in an independent model of the self and, as such, neglects social contexts and the psychologies of a majority of Americans. Given the prominence of independence in American ideas and institutions, the interdependent tendencies that arise from intersections of national culture with social class, race, and ethnicity go unrecognized and are often misunderstood and stigmatized. This unseen clash of independence and interdependence is a significant factor in many challenges, including those of education, employment, health, immigration, criminal justice, and political polarization.

  7. Compatibility in the Ustilago maydis-maize interaction requires inhibition of host cysteine proteases by the fungal effector Pit2.

    Directory of Open Access Journals (Sweden)

    André N Mueller

    2013-02-01

    Full Text Available The basidiomycete Ustilago maydis causes smut disease in maize, with large plant tumors being formed as the most prominent disease symptoms. During all steps of infection, U. maydis depends on a biotrophic interaction, which requires an efficient suppression of plant immunity. In a previous study, we identified the secreted effector protein Pit2, which is essential for maintenance of biotrophy and induction of tumors. Deletion mutants for pit2 successfully penetrate host cells but elicit various defense responses, which stops further fungal proliferation. We now show that Pit2 functions as an inhibitor of a set of apoplastic maize cysteine proteases, whose activity is directly linked with salicylic-acid-associated plant defenses. Consequently, protease inhibition by Pit2 is required for U. maydis virulence. Sequence comparisons with Pit2 orthologs from related smut fungi identified a conserved sequence motif. Mutation of this sequence caused loss of Pit2 function. Consequently, expression of the mutated protein in U. maydis could not restore virulence of the pit2 deletion mutant, indicating that the protease inhibition by Pit2 is essential for fungal virulence. Moreover, synthetic peptides of the conserved sequence motif showed full activity as protease inhibitor, which identifies this domain as a new, minimal protease inhibitor domain in plant-pathogenic fungi.

  8. VOC identification and inter-comparison from laboratory biomass burning using PTR-MS and PIT-MS

    Science.gov (United States)

    C. Warneke; J. M. Roberts; P. Veres; J. Gilman; W. C. Kuster; I. Burling; R. Yokelson; J. A. de Gouw

    2011-01-01

    Volatile organic compounds (VOCs) emitted from fires of biomass commonly found in the southeast and southwest U.S. were investigated with PTR-MS and PIT-MS, which are capable of fast measurements of a large number of VOCs. Both instruments were calibrated with gas standards and mass dependent calibration curves are determined. The sensitivity of the PIT-MS linearly...

  9. Chemical Composition of Date-Pits and Its Potential for Developing Value-Added Product - a Review

    Directory of Open Access Journals (Sweden)

    Hossain Mohammad Zakir

    2014-12-01

    Full Text Available Moisture, protein, oil and carbohydrate contents of date-pits varied from 3.1-12.5, 2.3-6.9, 5.0-12.5 and 70.9-86.9 g/100 g date-pits, respectively. BET-monolayer (i.e. strongly bound moisture content, solids-melting peak (at moisture: 6.7 g/100 g date-pits, and melting point of oil were 4.3 g/100 g dry-solids, 106oC, and 1.8oC, respectively. The major fatty acids were lauric, myristic, palmitic, stearic, oleic, and linoleic acids and polyphenol content varied from 21.0-62.0 mg/g date-pits depending on the varieties, types of solvent and temperature used for extraction. Date-pits showed effectives in animal and poultry feeds and it could be used as value added products, such as: dietary fibres, functional polysaccharides, caffeine-free drinks (similar to coffee, oil (biofuel or cooking oil, and other functional or medicinal products. Date-pits powder and activated carbon from date–pits showed effective in purifying water by removing different types of pollutants, such as heavy metals, boron, dyes, phenolic compounds, and pesticides. Date-pits also showed effective to be used as ingredient for composed, biomass, and fermentation processes.

  10. Do quantitative vessel and pit characters account for ion-mediated changes in the hydraulic conductance of angiosperm xylem?

    NARCIS (Netherlands)

    Jansen, S.; Gortan, E.; Lens, F.; Assunta Lo Gullo, M.; Salleo, S.; Scholtz, A.; Stein, A.; Trifilò, P.; Nardini, A.

    2011-01-01

    • The hydraulic conductance of angiosperm xylem has been suggested to vary with changes in sap solute concentrations because of intervessel pit properties. • The magnitude of the ‘ionic effect’ was linked with vessel and pit dimensions in 20 angiosperm species covering 13 families including six

  11. In-situ monitoring of pitting corrosion on vertically positioned 304 stainless steel by analyzing acoustic-emission energy parameter

    International Nuclear Information System (INIS)

    Wu, Kaige; Jung, Woo-Sang; Byeon, Jai-Won

    2016-01-01

    Highlights: • Pitting process in vertically positioned 304 SS is investigated by AE energy. • Gravity-influenced elongated pit, crack and rupture of pit cover were observed. • Hydrogen bubble evolution and pit covers rupturing were separately monitored by AE. • Four stages of AE energy were correlated with observed pitting mechanism. - Abstract: The acoustic emission (AE) energy was analyzed to monitor the pitting process on a vertically positioned 304-stainless steel. The gravity-dependent morphology of the elongated corrosion pits was observed. A scatter plot of the duration and energy indicated two AE clusters with different energy levels. There was a time delay after the detection of the low-energy hydrogen-bubble signals. Subsequently, high-energy signals were observed, whose AE source was attributed to large-scale cracks formed during the rupture of the elongated pit cover. An in-situ analysis of the AE energy evolution provided detailed insights into the corrosion process in relation to the specimen position.

  12. Closure Report for Corrective Action Unit 357: Mud Pits and Waste Dump, Nevada Test Site, Nevada, Rev. No.: 0

    Energy Technology Data Exchange (ETDEWEB)

    Laura A. Pastor

    2005-04-01

    This Closure Report (CR) presents information supporting closure of Corrective Action Unit (CAU) 357: Mud Pits and Waste Dump, Nevada Test Site (NTS), Nevada. The CR complies with the requirements of the Federal Facility Agreement and Consent Order (FFACO) that was agreed to by the State of Nevada, U.S. Department of Energy (DOE), and the U.S. Department of Defense (FFACO, 1996). Corrective Action Unit 357 is comprised of 14 Corrective Action Sites (CASs) located in Areas 1, 4, 7, 8, 10, and 25 of the NTS (Figure 1-1). The NTS is located approximately 65 miles (mi) northwest of Las Vegas, Nevada. Corrective Action Unit 357 consists of 11 CASs that are mud pits located in Areas 7, 8, and 10. The mud pits were associated with drilling activities conducted on the NTS in support of the underground nuclear weapons testing. The remaining three CASs are boxes and pipes associated with Building 1-31.2el, lead bricks, and a waste dump. These CAS are located in Areas 1, 4, and 25, respectively. The following CASs are shown on Figure 1-1: CAS 07-09-02, Mud Pit; CAS 07-09-03, Mud Pit; CAS 07-09-04, Mud Pit; CAS 07-09-05, Mud Pit; CAS 08-09-01, Mud Pit; CAS 08-09-02, Mud Pit; CAS 08-09-03, Mud Pit; CAS 10-09-02, Mud Pit; CAS 10-09-04, Mud Pit; CAS 10-09-05, Mud Pit; CAS 10-09-06, Mud Pit, Stains, Material; CAS 01-99-01, Boxes, Pipes; CAS 04-26-03, Lead Bricks; and CAS 25-15-01, Waste Dump. The purpose of the corrective action activities was to obtain analytical data that supports the closure of CAU 357. Environmental samples were collected during the investigation to determine whether contaminants exist and if detected, their extent. The investigation and sampling strategy was designed to target locations and media most likely to be contaminated (biased sampling). A general site conceptual model was developed for each CAS to support and guide the investigation as outlined in the Streamlined Approach for Environmental Restoration (SAFER) Plan (NNSA/NSO, 2003b). This CR

  13. Advantages and limitations for users of double pit pour-flush latrines: a qualitative study in rural Bangladesh

    Directory of Open Access Journals (Sweden)

    Faruqe Hussain

    2017-05-01

    Full Text Available Abstract Background In rural Bangladesh, India and elsewhere, pour-flush pit latrines are the most common sanitation system. When a single pit latrine becomes full, users must empty it themselves and risk exposure to fresh feces, pay an emptying service to remove pit contents or build a new latrine. Double pit pour-flush latrines may serve as a long-term sanitation option including high water table areas because the pits do not need to be emptied immediately and the excreta decomposes into reusable soil. Methods Double pit pour-flush latrines were implemented in rural Bangladesh for ‘hardcore poor’ households by a national NGO, BRAC. We conducted interviews, focus groups, and spot checks in two low-income, rural areas of Bangladesh to explore the advantages and limitations of using double pit latrines compared to single pit latrines. Results The rural households accepted the double pit pour-flush latrine model and considered it feasible to use and maintain. This latrine design increased accessibility of a sanitation facility for these low-income residents and provided privacy, convenience and comfort, compared to open defecation. Although a double pit latrine is more costly and requires more space than a single pit latrine the households perceived this sanitation system to save resources, because households did not need to hire service workers to empty pits or remove decomposed contents themselves. In addition, the excreta decomposition process produced a reusable soil product that some households used in homestead gardening. The durability of the latrine superstructures was a problem, as most of the bamboo-pole superstructure broke after 6–18 months of use. Conclusions Double pit pour-flush latrines are a long-term improved sanitation option that offers users several important advantages over single pit pour-flush latrines like in rural Bangladesh which can also be used in areas with high water table. Further research can provide an

  14. Advantages and limitations for users of double pit pour-flush latrines: a qualitative study in rural Bangladesh.

    Science.gov (United States)

    Hussain, Faruqe; Clasen, Thomas; Akter, Shahinoor; Bawel, Victoria; Luby, Stephen P; Leontsini, Elli; Unicomb, Leanne; Barua, Milan Kanti; Thomas, Brittany; Winch, Peter J

    2017-05-25

    In rural Bangladesh, India and elsewhere, pour-flush pit latrines are the most common sanitation system. When a single pit latrine becomes full, users must empty it themselves and risk exposure to fresh feces, pay an emptying service to remove pit contents or build a new latrine. Double pit pour-flush latrines may serve as a long-term sanitation option including high water table areas because the pits do not need to be emptied immediately and the excreta decomposes into reusable soil. Double pit pour-flush latrines were implemented in rural Bangladesh for 'hardcore poor' households by a national NGO, BRAC. We conducted interviews, focus groups, and spot checks in two low-income, rural areas of Bangladesh to explore the advantages and limitations of using double pit latrines compared to single pit latrines. The rural households accepted the double pit pour-flush latrine model and considered it feasible to use and maintain. This latrine design increased accessibility of a sanitation facility for these low-income residents and provided privacy, convenience and comfort, compared to open defecation. Although a double pit latrine is more costly and requires more space than a single pit latrine the households perceived this sanitation system to save resources, because households did not need to hire service workers to empty pits or remove decomposed contents themselves. In addition, the excreta decomposition process produced a reusable soil product that some households used in homestead gardening. The durability of the latrine superstructures was a problem, as most of the bamboo-pole superstructure broke after 6-18 months of use. Double pit pour-flush latrines are a long-term improved sanitation option that offers users several important advantages over single pit pour-flush latrines like in rural Bangladesh which can also be used in areas with high water table. Further research can provide an understanding of the comparative health impacts and effectiveness of the model

  15. Improving pitting corrosion resistance of type 304 austenitic stainless steel pipe weldments using purging gases with low amounts of oxygen

    International Nuclear Information System (INIS)

    Huang, W.; Paciej, R.; Link, L.; Mckeown, M.

    1993-01-01

    Pitting corrosion on the welded joints of water pipe lines may cause the shut down of nuclear power plants. The susceptibility to pitting corrosion is usually increased by high temperature oxidation during welding. In this study, an attempt was made to improve the pitting corrosion resistance of type 304 austenitic stainless steel pipe weldments by reducing the oxygen level in the purging gases. The pitting corrosion resistance of the as-received weldments was determined using stepwise cyclic polarization in aqueous solution containing chloride ions. It was found that relatively high oxygen levels (1-2%) in the purging gases caused severe high temperature oxidation, resulting in a non-uniform, porous, cracked, and thick surface oxide layer on the fusion and heat affected zones on the root pass of the pipe weldments. This high temperature oxidation also created a non-uniform distribution of chromium in the surface oxide layer, which, in turn, caused preferential pitting in the chromium depleted areas

  16. An effective thickness proposal for strength evaluation of one-side pitted steel plates under uniaxial compression

    Directory of Open Access Journals (Sweden)

    Zorareh Hadj Mohammad Esmaeil Nouri

    Full Text Available This paper presents the results of an investigation into the post-buckling behaviour and ultimate strength of imperfect pitted steel plates used in ship and other marine-related structures. A series of elastic-plastic large deflection finite element analyses is performed on pitted steel plates. The effects of pitting corrosion on one side of the plates are introduced into the finite element models. The effects on plate compressive strength as a result of parametric variation of the pitting corrosion geometry are evaluated. A proposal on the effective thickness is concluded in order to estimate the ultimate strength and explore the post-buckling behaviour of pitted steel plates under uniaxial compression.

  17. Pit Bull attack causing limb threatening vascular trauma —A case series

    Directory of Open Access Journals (Sweden)

    Patrick Harnarayan

    2018-01-01

    Conclusion: Attacks by Pit Bull Terriers are more likely to cause severe morbidity than other breeds of dogs. Immediate surgical exploration is required to prevent catastrophic outcomes, especially limb loss. Stronger animal control laws, public education and responsible dog ownership may reduce deaths from these canines.

  18. Special Analysis: Disposal Plan for Pit 38 at Technical Area 54, Area G

    International Nuclear Information System (INIS)

    French, Sean B.; Shuman, Rob

    2012-01-01

    have been made to utilize the remaining disposal capacity within MDA G to the greatest extent possible. One approach for doing this has been to dispose of low-activity waste from cleanup operations at LANL in the headspace of selected disposal pits. Waste acceptance criteria (WAC) for the material placed in the headspace of pits 15, 37, and 38 have been developed (LANL, 2010) and the impacts of placing waste in the headspace of these units has been evaluated (LANL, 2012a). The efforts to maximize disposal efficiency have taken on renewed importance because of the disposal demands placed on MDA G by the large volumes of waste that are being generated at LANL by cleanup efforts. For example, large quantities of waste were recently generated by the retrieval of waste formerly disposed of at TA-21, MDA B. A portion of this material has been disposed of in the headspace of pit 38 in compliance with the WAC developed for that disposal strategy; a large amount of waste has also been sent to off-site facilities for disposal. Nevertheless, large quantities of MDA B waste remain that require disposal. An extension of pit 38 was proposed to provide the disposal capacity that will be needed to dispose of institutional waste and MDA B waste through 2013. A special analysis was prepared to evaluate the impacts of the pit extension (LANL, 2012b). The analysis concluded that the disposal unit could be extended with modest increases in the exposures projected for the Area G performance assessment and composite analysis, as long as limits were placed on the radionuclide concentrations in the waste that is placed in the headspace of the pit. Based, in part, on the results of the special analysis, the extension of pit 38 was approved and excavation of the additional disposal capacity was started in May 2012. The special analysis presented here uses performance modeling to identify a disposal plan for the placement of waste in pit 38. The modeling uses a refined design of the disposal unit

  19. Deafness and permanently reduced potassium channel gene expression and function in hypothyroid Pit1dw mutants

    Science.gov (United States)

    Mustapha, Mirna; Fang, Qing; Gong, Tzy-Wen; Dolan, David F.; Raphael, Yehoash; Camper, Sally A.; Duncan, R. Keith

    2012-01-01

    The absence of thyroid hormone (TH) during late gestation and early infancy can cause irreparable deafness in both humans and rodents. A variety of rodent models have been utilized in an effort to identify the underlying molecular mechanism. Here, we characterize a mouse model of secondary hypothyroidism, pituitary transcription factor 1 (Pit1dw), which has profound, congenital deafness that is rescued by oral TH replacement. These mutants have tectorial membrane abnormalities, including a prominent Hensen's stripe, elevated β-tectorin composition, and disrupted striated-sheet matrix. They lack distortion product otoacoustic emissions and cochlear microphonic responses, and exhibit reduced endocochlear potentials, suggesting defects in outer hair cell function and potassium recycling. Auditory system and hair cell physiology, histology and anatomy studies reveal novel defects of hormone deficiency related to deafness: (1) permanently impaired expression of KCNJ10 in the stria vascularis of Pit1dw mice, which likely contributes to the reduced endocochlear potential, (2) significant outer hair cell loss in the mutants, which may result from cellular stress induced by the lower KCNQ4 expression and current levels in Pit1dw mutant outer hair cells and (3) sensory and strial cell deterioration, which may have implications for thyroid hormone dysregulation in age related hearing impairment. In summary, we suggest that these defects in outer hair cell and strial cell function are important contributors to the hearing impairment in Pit1dw mice. PMID:19176829

  20. Multiple pituitary hormone deficiency caused by Pit-I mutation and ...

    African Journals Online (AJOL)

    Conclusions: There were challenges to management such as, inadequate facility for diagnosis, huge cost of treatment and little awareness about childhood endocrine conditions amongst health workers in a developing economy. Keywords: Multiple pituitary hormone deficiency (MPHD), PIT-1 mutation, short stature, ...

  1. Propagation of pitting corrosion of steel in concrete: conceptual models for local cross section loss

    NARCIS (Netherlands)

    Polder, R.B.; Angst, U.M.; Pacheco, J.; Peelen, W.H.A.

    2016-01-01

    Where exposed to an aggressive environment, concrete structures will develop reinforcement corrosion at some point in their life. Chloride ions from de-icing salt or sea water induce pitting corrosion. Local cross section reduction may occur relatively quickly and expansion due to corrosion products

  2. Study on monitoring of deep foundation pit with SMW engineering method plus anchor cable retaining structure

    Science.gov (United States)

    Chen, Wenzhao; Cui, Wenping

    2018-03-01

    The SMW method has many advantages, such as little influence on the surrounding environment, good watertight performance, wide range of application, short construction period, low cost and so on. In this paper, we chose the SMW engineering method combined with anchor cable to support structure in the second phase deep foundation pit of Jinan LuJinDongCheng as the research object, monitored and analysed the horizontal displacement of the pile top, Peripheral surface subsidence and internal force of the anchor cable in the foundation pit. We also discussed the displacement, internal force of anchor cable and the settlement of surrounding environment in the excavation of foundation pit and in different stages of construction. Conclusion:(1)The maximum horizontal displacement of the retaining structure is closely related to the depth and time of excavation, the construction of anchor cable can well limit the deformation of pile body; (2)Groundwater seepage caused by foundation pit dewatering will change the effective stress of soil. The change of groundwater level has an important influence on the working behavior of smw anchor cable supporting structure.

  3. The use of holmium-yttrium aluminum garnet laser as pit and fissure cleaner

    Directory of Open Access Journals (Sweden)

    Armasastra Bahar

    2009-09-01

    Full Text Available Background: The prevention and management of pit and fissure caries has become relatively more important in recent times. There is a need for an effective preventive measure against pit and fissure caries. Purpose: The purpose of this study was to investigate the effect of laser beam as a cleaning method of pits and fissures. Methods: Ho-YAG laser which has a wavelength of 2.1 µm was used in this experiment. The specimens were extracted human teeth. The effect of three cleaning methods was examined comparatively by scoring the cleaned area of fissure, namely laser irradiation with Ho-YAG laser, chemico-mechanical with combination of 10% NaOCl and ultrasonic scaler and mechanical with ultrasonic scaler. Vertico-bucco-lingual serial ground sections of each tooth were observed under light microscopy. Scoring the depth of cleaned area was performed by comparing the depth of fissure. result: Progressive result was obtained on the cleaning effect of three methods laser irradiation methods which was the most effective compared to other methods but statistically was not significant. Cleaned area of laser irradiation method was 48.91%, chemico-mechanical method was 41.77% and mechanical method was 36.78%. Conclusion: Holmium -yttrium aluminum garner laser is a relatively new method for pit and fissure cleaning even though the effectivity is not yet maximal. More research is needed to maximize the use of this laser.

  4. Spironolactone ameliorates PIT1-dependent vascular osteoinduction in klotho-hypomorphic mice.

    Science.gov (United States)

    Voelkl, Jakob; Alesutan, Ioana; Leibrock, Christina B; Quintanilla-Martinez, Leticia; Kuhn, Volker; Feger, Martina; Mia, Sobuj; Ahmed, Mohamed S E; Rosenblatt, Kevin P; Kuro-O, Makoto; Lang, Florian

    2013-02-01

    Klotho is a potent regulator of 1,25-hydroxyvitamin D3 [1,25(OH)2D3] formation and calcium-phosphate metabolism. Klotho-hypomorphic mice (kl/kl mice) suffer from severe growth deficits, rapid aging, hyperphosphatemia, hyperaldosteronism, and extensive vascular and soft tissue calcification. Sequelae of klotho deficiency are similar to those of end-stage renal disease. We show here that the mineralocorticoid receptor antagonist spironolactone reduced vascular and soft tissue calcification and increased the life span of kl/kl mice, without significant effects on 1,25(OH)2D3, FGF23, calcium, and phosphate plasma concentrations. Spironolactone also reduced the expression of osteoinductive Pit1 and Tnfa mRNA, osteogenic transcription factors, and alkaline phosphatase (Alpl) in calcified tissues of kl/kl mice. In human aortic smooth muscle cells (HAoSMCs), aldosterone dose-dependently increased PIT1 mRNA expression, an effect paralleled by increased expression of osteogenic transcription factors and enhanced ALP activity. The effects of aldosterone were reversed by both spironolactone treatment and PIT1 silencing and were mitigated by FGF23 cotreatment in HAoSMCs. In conclusion, aldosterone contributes to vascular and soft tissue calcification, an effect due, at least in part, to stimulation of spironolactone-sensitive, PIT1-dependent osteoinductive signaling.

  5. Development of optimal terrace pit coal mining systems. Technical progress report, October 1- October 31, 1979

    Energy Technology Data Exchange (ETDEWEB)

    McIntosh, D. G.

    1979-11-19

    A bibliography on various aspects of optimal terrace pit coal mining systems is included. Relevant federal and state legislation and regulations have been identified. Mines of interest to the project have been identified and listed for field visits. Seven regions of different climates, hydrology, geology, etc., are being studied individually. (LTN)

  6. Influence of pitting defects on quality of high power laser light field

    Science.gov (United States)

    Ren, Huan; Zhang, Lin; Yang, Yi; Shi, Zhendong; Ma, Hua; Jiang, Hongzhen; Chen, Bo; Yang, XiaoYu; Zheng, Wanguo; Zhu, Rihong

    2018-01-01

    With the split-step-Fourier-transform method for solving the nonlinear paraxial wave equation, the intensity distribution of the light field when the pits diameter or depth change is obtained by using numerical simulation, include the intensity distribution inside optical element, the beam near-field, the different distances behind the element and the beam far-field. Results show that with the increase of pits diameter or depth, the light field peak intensity and the contrast inside of element corresponding enhancement. The contrast of the intensity distribution of the rear surface of the element will increase slightly. The peak intensity produced by a specific location element downstream of thermal effect will continue to increase, the damage probability in optics placed here is greatly increased. For the intensity distribution of the far-field, increase the pitting diameter or depth will cause the focal spot intensity distribution changes, and the energy of the spectrum center region increase constantly. This work provide a basis for quantitative design and inspection for pitting defects, which provides a reference for the design of optical path arrangement.

  7. Electromagnetic Simulations of Ground-Penetrating Radar Propagation near Lunar Pits and Lava Tubes

    Science.gov (United States)

    Zimmerman, M. I.; Carter, L. M.; Farrell, W. M.; Bleacher, J. E.; Petro, N. E.

    2013-01-01

    Placing an Orion capsule at the Earth-Moon L2 point (EML2) would potentially enable telerobotic operation of a rover on the lunar surface. The Human Exploration Virtual Institute (HEVI) is proposing that rover operations be carried out near one of the recently discovered lunar pits, which may provide radiation shielding for long duration human stays as well as a cross-disciplinary, science-rich target for nearer-term telerobotic exploration. Ground penetrating radar (GPR) instrumentation included onboard a rover has the potential to reveal many details of underground geologic structures near a pit, as well as characteristics of the pit itself. In the present work we employ the full-wave electromagnetic code MEEP to simulate such GPR reflections from a lunar pit and other subsurface features including lava tubes. These simulations will feed forward to mission concepts requiring knowledge of where to hide from harmful radiation and other environmental hazards such as plama charging and extreme diurnal temperatures.

  8. Pitting and stress corrosion cracking behavior in welded austenitic stainless steel

    International Nuclear Information System (INIS)

    Lu, B.T.; Chen, Z.K.; Luo, J.L.; Patchett, B.M.; Xu, Z.H.

    2005-01-01

    The effect of microstructural changes in 304 austenitic stainless steel induced by the processes of gas tungsten arc welding (GTAW) and laser-beam welding (LBW) on the pitting and stress corrosion cracking (SCC) behaviors was investigated. According to the in situ observations with scanning reference electrode technique (SRET) and the breakdown potentials of the test material with various microstructures, the GTAW process made the weld metal (WM) and heat-affected zone (HAZ) more sensitive to pitting corrosion than base metal (BM), but the LBW process improved the pitting resistance of the WM. In the initiation stage of SCC, the cracks in the BM and HAZ propagated in a transgranular mode. Then, the crack growth mechanism changed gradually into a mixed transgranular + intergranular mode. The cracks in the WM were likely to propagate along the dendritic boundaries. The crack initiation rate, crack initiation lifetime and crack propagation rate indicated that the high-to-low order of SCC resistance is almost the same as that for pitting resistance. High heat-input (and low cooling rate) was likely to induce the segregation of alloying elements and formation of Cr-depleted zones, resulting in the degradation in the corrosion resistance

  9. Ecological risk of reprocessing of uranium wastes of the Gafurov-city's tailing pit

    International Nuclear Information System (INIS)

    Hakimov; Nazarov, H.M.; Mirsaidov, U.M.

    2005-01-01

    The authors set as their purpose the investigation of ecological risk of reprocessing of uranium wastes of the Gafurov-city's tailing pit. Having carried out their investigations, the authors came to the conclusion that the effect of radon gas during reprocessing to workers and specialists is minimal if they follow all the required safety rules

  10. Mechanism of pitting corrosion protection of metals and alloys in new-generation water treatment plants

    Directory of Open Access Journals (Sweden)

    Grachev Vladimir

    2017-01-01

    Full Text Available In this article authors set out a principle of pitting corrosion protection, suggested a new class of multilayer materials with high corrosion resistance. They substantiated the choice of the layers for the multilayer material designed for exploitation in oxidizing and non-oxidizing environment. The sphere of application of the multilyer materials was defined.

  11. Pitting Corrosion of Copper in Waters with High pH and Low Alkalinity

    Science.gov (United States)

    Localized or pitting corrosion of copper pipes used in household drinking-water plumbing is a problem for many water utilities and their customers. Extreme attack can lead to pinhole water leaks that may result in water damage, mold growth, and costly repairs. Water quality has b...

  12. Monitoring of Open-pit mining using geomorphometry and Unmanned Aerial Vehicles (UAVs)

    Science.gov (United States)

    Xiang, Jie; Chen, Jianping; Sofia, Giulia; Lai, Zili; Huang, Haozhong; Tarolli, Paolo

    2017-04-01

    Mining activities have a significant impact on the Earth's surface, and open-pit mines are the most evident landscape signatures of the mining operations. Despite the importance of such human impacts, an open challenge for the Earth Science community is to explore a fast, accurate and low-cost method to monitor changes in open-pit mining. The main goal of this work is to develop such a methodology. In this study, we used an Unmanned Aerial Vehicle(UAV) to collect two series of photographs(August 2014 and October 2016). Through the structure from motion (SfM) photogrammetric techniques, the images were used to generate high-resolution Digital Surface Models (DSMs). DSMs were co-registered by seven ground control points, and the accuracy of the co-registration was checked and corrected by comparing non-change areas. Finally, two kinds of landscape metric were used to detect the changes: (1) the Slope Local Length of Auto-Correlation (SLLAC)(Sofia et al., 2014), which allows to estimate the surface covered by open-pit mining by using a simple empirical model; (2) the DSM of Difference (DoD) , which calculated the changes between two DSMs on a cells-by-cells basis, to accurately estimate the volumetric changes. The results underline the effectiveness of the UAV survey techniques and adopted landscape metrics. This study has demonstrated a robust and rapid workflow to dynamic monitor the open-pit mine and support sustainable environmental planning.

  13. Epsin 1 is involved in recruitment of ubiquitinated EGF receptors into clathrin-coated pits

    DEFF Research Database (Denmark)

    Kazazic, Maja; Bertelsen, Vibeke; Pedersen, Ketil Winther

    2008-01-01

    . Furthermore, RNAi-mediated knock down of epsin 1 was found to inhibit internalization of the EGFR, while having no effect on endocytosis of the transferrin receptor. Additionally, upon knock down of epsin 1, translocation of the EGFR to central parts of clathrin-coated pits was inhibited. This supports...

  14. Probabilistic models for steel corrosion loss and pitting of marine infrastructure

    International Nuclear Information System (INIS)

    Melchers, R.E.; Jeffrey, R.J.

    2008-01-01

    With the increasing emphasis on attempting to retain in service ageing infrastructure models for the description and prediction of corrosion losses and for maximum pit depth are of increasing interest. In most cases assessment and prediction will be done in a probabilistic risk assessment framework and this then requires probabilistic corrosion models. Recently, novel models for corrosion loss and maximum pit depth under marine immersion conditions have been developed. The models show that both corrosion loss and pit depth progress in a non-linear fashion with increased exposure time and do so in a non-monotonic manner as a result of the controlling corrosion process changing from oxidation to being influenced by bacterial action. For engineers the importance of this lies in the fact that conventional 'corrosion rates' have no validity, particularly for the long-term corrosion effects as relevant to deteriorated infrastructure. The models are consistent with corrosion science principles as well as current understanding of the considerable influence of bacterial processes on corrosion loss and pitting. The considerable practical implications of this are described

  15. Cavitation pitting and erosion of Al 6061-T6 in mineral oil and water

    Science.gov (United States)

    Rao, B. C. S.; Buckley, D. H.

    1983-01-01

    The authors are currently carrying out a study of the cavitation erosion of different bearing metals and alloys in mineral oils were studied. The variations of weight loss, the pit diameter and depth due to cavitation erosion on Al 6061-T6 in mineral oil and water are presented.

  16. The pit ventilation features and the design principle of ventilation system in trackless mining uranium mine

    International Nuclear Information System (INIS)

    Deng Wenhui; Zhou Xinghuo; Li Xianjie

    2001-01-01

    According to the pit arrangement features of trackless mining uranium mine, based on the fundamental of radon permeation and control, and analysis of radon pollution characteristics and radon education, the design principle of ventilation system in trackless mining uranium mine has been raised

  17. The Use of Pit and Fissure Sealants—A Literature Review

    Directory of Open Access Journals (Sweden)

    Reem Naaman

    2017-12-01

    Full Text Available This paper reviews the literature and discusses the latest updates on the use of pit and fissure sealants. It demonstrates the effectiveness of pit and fissure sealants in preventing caries and the management of early carious lesions. It compares the use of different sealant materials and their indications. It describes the application technique for sealants. It also reviews the cost-effectiveness of sealants as a preventive strategy. From this review and after the discussion of recently published studies on pit and fissure sealants, it is evident that sealants are effective in caries prevention and in preventing the progression of incipient lesions. It is therefore recommended that pit and fissure sealant be applied to high-caries-risk children for optimum cost-effectiveness. It is a highly sensitive technique that needs optimum isolation, cleaning of the tooth surface, etching, and the application of a thin bonding layer for maximum benefit. Recall and repair, when needed, are important to maximize the effectiveness of such sealant use.

  18. The Use of Pit and Fissure Sealants—A Literature Review

    Science.gov (United States)

    Naaman, Reem; El-Housseiny, Azza A.; Alamoudi, Najlaa

    2017-01-01

    This paper reviews the literature and discusses the latest updates on the use of pit and fissure sealants. It demonstrates the effectiveness of pit and fissure sealants in preventing caries and the management of early carious lesions. It compares the use of different sealant materials and their indications. It describes the application technique for sealants. It also reviews the cost-effectiveness of sealants as a preventive strategy. From this review and after the discussion of recently published studies on pit and fissure sealants, it is evident that sealants are effective in caries prevention and in preventing the progression of incipient lesions. It is therefore recommended that pit and fissure sealant be applied to high-caries-risk children for optimum cost-effectiveness. It is a highly sensitive technique that needs optimum isolation, cleaning of the tooth surface, etching, and the application of a thin bonding layer for maximum benefit. Recall and repair, when needed, are important to maximize the effectiveness of such sealant use. PMID:29563440

  19. Remedial investigation and feasibility study for the Lawrence Livermore National Laboratory Site 300 Pit 7 Complex

    Energy Technology Data Exchange (ETDEWEB)

    Taffet, M.J. (Lawrence Livermore National Lab., CA (USA)); Oberdorfer, J.A. (San Jose State Univ., CA (USA)); McIlvride, W.A. (Weiss Associates, Oakland, CA (USA))

    1989-10-01

    This report summarizes the results and conclusions of the investigation of tritium and other compounds in ground water in the vicinity of landfills at the Lawrence Livermore National Laboratory (LLNL) Site 300 Pit 7 Complex. 91 refs., 110 figs., 43 tabs.

  20. Atomic force microscopy of the intervessel pit membrane in the stem of Sapium sebiferum (Euphorbiacea)

    Science.gov (United States)

    Thomas C. Pesacreta; Leslie H. Groom; Timothy G. Rials

    2005-01-01

    Sapwood and juvenile wood of Sapium sebiferum (Euphorbiacea) was collected during 2000-2002. In air-dried vessel elements, the surface of pit membranes (PMs) in the outermost growth ring was coated with plaque-like or interstitial material that was 2-5 nm thick. This coating was phase dark and overlaid a phase bright layer of globules and...