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Sample records for baltic ringed seals

  1. Seasonal activity budget of adult baltic ringed seals.

    Directory of Open Access Journals (Sweden)

    Tero Harkonen

    Full Text Available Although ringed seals are important components in oceanic and fresh water ecosystems at high latitudes, little is known about how they exploit these harsh environments. Seasonal activity and diving behaviour of 19 adult Baltic ringed seals were studied by satellite telemetry. We elaborated an activity budget for ten months of the year, extending over the period from moult to the breeding season. Seals from three main regions showed explicit site fidelity and the distributions of animals tagged from different areas did not overlap, suggesting separate stocks. Both the mean duration and the mean depth of dives peaked in June and July. Seals spent 70% (females to 85% (males of their time diving in June and July which decreased to 50% in late autumn. Less than one percent of dives exceeded 10 min in females, while 10% of male dives lasted longer than 10 min in June to September. Less than one percent of dives lasted for more than 25 min. Both females and males were most active during day time and hauled out predominantly during the night. Activity patterns during the summer are suggested to be correlated to energy accumulation and prey availability. The information on seasonal activity budget is crucial for developing population energetic models where interactions between ringed seals and other trophic levels can be evaluated.

  2. Concentrations, patterns and metabolites of organochlorine pesticides in relation to xenobiotic phase I and II enzyme activities in ringed seals (Phoca hispida) from Svalbard and the Baltic Sea

    Energy Technology Data Exchange (ETDEWEB)

    Routti, Heli, E-mail: heli.routti@npolar.n [Norwegian Polar Institute, Polar Environmental Centre, 9296 Tromso (Norway); Centre of Excellence in Evolutionary Genetics and Physiology, Department of Biology, University of Turku, 20014 Turku (Finland); Bavel, Bert van [MTM Research Centre, Orebro University, 70182 Orebro (Sweden); Letcher, Robert J. [Wildlife Toxicology and Disease Program, Wildlife and Landscape Science Directorate, Science and Technology Branch, Environment Canada, National Wildlife Research Centre, Carleton University, Ottawa, Ontario K1A 0H3 (Canada); Arukwe, Augustine [Department of Biology, Norwegian University of Science and Technology, 7491 Trondheim (Norway); Chu Shaogang [Wildlife Toxicology and Disease Program, Wildlife and Landscape Science Directorate, Science and Technology Branch, Environment Canada, National Wildlife Research Centre, Carleton University, Ottawa, Ontario K1A 0H3 (Canada); Gabrielsen, Geir W. [Norwegian Polar Institute, Polar Environmental Centre, 9296 Tromso (Norway)

    2009-08-15

    The present study investigates the concentrations and patterns of organochlorine pesticides (OCPs) and their metabolites in liver and plasma of two ringed seal populations (Phoca hispida): lower contaminated Svalbard population and more contaminated Baltic Sea population. Among OCPs, p,p'-DDE and sum-chlordanes were the highest in concentration. With increasing hepatic contaminant concentrations and activities of xenobiotic-metabolizing enzymes, the concentrations of 3-methylsulfonyl-p,p'-DDE and the concentration ratios of pentachlorophenol/hexachlorobenzene increased, and the toxaphene pattern shifted more towards persistent Parlar-26 and -50 and less towards more biodegradable Parlar-44. Relative concentrations of the chlordane metabolites, oxychlordane and -heptachlorepoxide, to sum-chlordanes were higher in the seals from Svalbard compared to the seals from the Baltic, while the trend was opposite for cis- and trans-nonachlor. The observed differences in the OCP patterns in the seals from the two populations are probably related to the catalytic activity of xenobiotic-metabolizing enzymes, and also to differences in dietary exposure. - Contrasting patterns of organochlorine pesticides in two ringed seal populations.

  3. Ringed Seal Distribution Map

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains GIS layers that depict the known spatial distributions (i.e., ranges) of the five subspecies of ringed seals (Phoca hispida). It was produced...

  4. Grey seal predation on forage fish in the Baltic Sea

    DEFF Research Database (Denmark)

    Eero, Aro; Neuenfeldt, Stefan; Aho, Teija;

    has increased accordingly. The diet of grey seal in the Baltic consists of ca. 20 fish species. The most abundant prey items in the Baltic proper are Baltic herring, sprat, and cod, and in the Bothnian Sea and Bothnian Bay Baltic herring, Coregonus sp., Baltic salmon, and sea trout. An adult seal...... consumes on average round 4.5 kg fish per day, of which 55% are clupeoids in the Baltic Main basin and 70% in the Bothnian Sea and Bothnian Bay. According to acoustic estimates, predator– prey distribution patterns, migration patterns, and multispecies analysis (SMS), the predation effect of grey seals...... on Baltic herring and sprat stocks is still at a very low level. Hence, with present grey seal stock sizes, the impact of seal predation can be ignored in whole Baltic‐scale herring and sprat stock management considerations. Locally, however, grey seal–fishery interactions play an important role and should...

  5. POP load and vitamins as potential biomarkers in the Baltic seals

    Energy Technology Data Exchange (ETDEWEB)

    Routti, H.; Nyman, M.; Helle, E. [Finnish Game and Fisheries Research Inst., Helsinki (Finland); Backman, C. [National Veterinary and Food Research Inst. (Finland); Koistinen, J. [Div. of Environmental Health, National Public Health Inst. (Finland)

    2004-09-15

    Exceptionally high levels of polychlorinated biphenyls (PCB) and 1,1,1.trichloro- 2,2-bis[p-chlorophenyl]ethane (DDT) and its metabolites were reported in the Baltic seals in the late 1960s and early 1970s. PCB levels in ringed seals, in particular, are still high enough to threaten the well being of the animals. The observed difference in contaminant pattern between ringed and grey seals in the Baltic has not been explained, but could be partly due to species-specific food sources. Several pathological and biochemical changes observed in the Baltic seals correlate with the individual POP loads. Of the observed biochemical changes, elevated cytochrome P4501A (CYP1A) levels, decreased liver vitamin A stores and increased vitamin E levels in blubber or plasma, have been proposed as possible biomarkers of contaminant load in Baltic seals. However, as the vitamin A and E status of marine mammals also reflects the nutritional vitamin level, the lower vitamin A and elevated vitamin E levels observed in the Baltic seals could be a reflection of the levels of these vitamins in their food sources. The aim of this study was to investigate the contaminant load in the Baltic seals and to evaluate the utility level of potential exposure and effect biomarkers. Seals from less contaminated areas were used as reference material (Svalbard and Sable Island, Canada). In the present study, POP and vitamin levels were also studied in seal prey species in order to study the transfer of these compounds to grey and ringed seals from their main food sources.

  6. Seal dynamics on the Swedish west coast: Scenarios of competition as Baltic grey seal intrude on harbour seal territory

    Science.gov (United States)

    Svensson, Carl Johan

    2012-07-01

    The Kattegat-Skagerrak region on the Swedish west coast is home to an abundant harbour seal population (Phoca vitulina) and a small scattered grey seal population (Halichoerus grypus). In addition, grey seal from the growing population in the Baltic Sea frequently migrate into the Kattegat-Skagerrak. Harbour seals on the west coast of Sweden show relatively high population growth (approximately 9%) compared to the Baltic grey seal in ice-free habitats (approximately 6%), which, in theory, makes harbour seal the stronger competitor of the two in this region. However, incidents of disease in harbour seals that lower population growth are becoming more frequent. These epidemics are primarily caused by the Phocine Distemper Virus (PDV), and may reduce population size with up to 70%. This study models the average development under potential scenarios of competing harbour- and Baltic grey seal populations using Leslie matrices and the Lotka-Volterra model of inter-specific competition. The model is parameterised with previously published data, and resource overlap is incorporated through density dependent pup survival. Using numerical methods short- and long-term abundances are simulated under weak, moderate and strong competition and for different frequencies of PDV epidemics. Results show that the harbour seals are resilient to competition while exerting a negative effect on grey seal abundance under moderate to strong competition. Hence Baltic grey seal benefit from weaker levels of competition. Under moderate and strong competition grey seal abundance is a direct function of the PDV frequency as this reduces the competitive strength of harbour seals. Theoretically this means that higher frequencies of PDV or other pathogens epidemics could facilitate an expansion of Baltic grey seal into Kattegat-Skagerrak. Independent of interaction strength and frequency of epidemics the projected changes to abundances are slow (50-100 years), and even in exceedingly stable

  7. Could seals prevent cod recovery in the Baltic Sea?

    Directory of Open Access Journals (Sweden)

    Brian R MacKenzie

    Full Text Available Fish populations are increasingly affected by multiple human and natural impacts including exploitation, eutrophication, habitat alteration and climate change. As a result many collapsed populations may have to recover in ecosystems whose structure and functioning differ from those in which they were formerly productive and supported sustainable fisheries. Here we investigate how a cod (Gadus morhua population in the Baltic Sea whose biomass was reduced due to a combination of high exploitation and deteriorating environmental conditions might recover and develop in the 21st century in an ecosystem that likely will change due to both the already started recovery of a cod predator, the grey seal Halichoerus grypus, and projected climate impacts. Simulation modelling, assuming increased seal predation, fishing levels consistent with management plan targets and stable salinity, shows that the cod population could reach high levels well above the long-term average. Scenarios with similar seal and fishing levels but with 15% lower salinity suggest that the Baltic will still be able to support a cod population which can sustain a fishery, but biomass and yields will be lower. At present knowledge of cod and seal interactions, seal predation was found to have much lower impact on cod recovery, compared to the effects of exploitation and salinity. These results suggest that dual management objectives (recovery of both seal and cod populations are realistic but success in achieving these goals will also depend on how climate change affects cod recruitment.

  8. mRNA expression of genes regulating lipid metabolism in ringed seals (Pusa hispida) from differently polluted areas

    Energy Technology Data Exchange (ETDEWEB)

    Castelli, Martina Galatea [Norwegian Polar Institute, Fram Centre, 9296 Tromsø (Norway); University of Bergen, Department of Biology, 5020 Bergen (Norway); Rusten, Marte; Goksøyr, Anders [University of Bergen, Department of Biology, 5020 Bergen (Norway); Routti, Heli, E-mail: heli.routti@npolar.no [Norwegian Polar Institute, Fram Centre, 9296 Tromsø (Norway)

    2014-01-15

    Highlights: •Genes regulating lipid metabolism were studied in ringed seals. •We compared highly contaminated Baltic seals and less contaminated Svalbard seals. •mRNA expression of hepatic PPARγ was higher in the Baltic seals. •mRNA expression of adipose PPARγ target genes was higher in the Baltic seals. •Contaminant exposure may affect lipid metabolism in the Baltic ringed seals. -- Abstract: There is a growing concern about the ability of persistent organic pollutants (POPs) to influence lipid metabolism. Although POPs are found at high concentrations in some populations of marine mammals, for example in the ringed seal (Pusa hispida) from the Baltic Sea, little is known about the effects of POPs on their lipid metabolism. An optimal regulation of lipid metabolism is crucial for ringed seals during the fasting/molting season. This is a physiologically stressful period, during which they rely on the energy stored in their fat reserves. The mRNA expression levels for seven genes involved in lipid metabolism were analyzed in liver and/or blubber tissue from molting ringed seals from the polluted Baltic Sea and a less polluted reference location, Svalbard (Norway). mRNA expression of genes encoding peroxisome proliferator-activated receptors (PPAR) α and γ and their target genes acyl-coenzyme A oxidase 1 (ACOX1) and cluster of differentiation 36 (CD36) were analyzed in liver. mRNA expression level of genes encoding PPARβ, PPARγ and their target genes encoding fatty acid binding protein 4 (FABP4) and adiponectin (ADIPOQ) were measured in inner and middle blubber layers. In addition, we evaluated the influence of molting status on hepatic mRNA expression of genes encoding PPARs and their target genes in ringed seals from Svalbard. Our results show higher mRNA expression of genes encoding hepatic PPARγ and adipose PPARβ, FABP4, and ADIPOQ in the Baltic seals compared to the Svalbard seals. A positive relationship between mRNA expressions of genes

  9. Heartworm (Acanthocheilonema spirocauda) and seal louse (Echinophthirius horridus) infections in harbour seals (Phoca vitulina) from the North and Baltic Seas

    Science.gov (United States)

    Lehnert, Kristina; Schwanke, Eva; Hahn, Kerstin; Wohlsein, Peter; Siebert, Ursula

    2016-07-01

    The seal louse (Echinophthirius [E.] horridus) and the heartworm (Acanthocheilonema [A.] spirocauda) are parasites of harbour seal (Phoca vitulina). Little is known about the role of the seal louse as a potential vector and its role for the development and transmission of heartworm larvae to their final host, the harbour seal. The life-cycle of the heartworm is still not fully understood. For the presented study, findings of 1191 stranded harbour seals collected along the North- and Baltic Sea coast between 1996 and 2013 were examined. 4.4% (n = 53) of these harbour seals were infected with adult heartworms and 3.4% (n = 40) harbour seals carried seal lice. The highest prevalence and level of infection with adult heartworms (A. spirocauda) (9.3%) and seal lice (E. horridus) (8.9%) were found on yearling harbour seals (7-18 months) compared to neonate and adult seals. Investigating seal lice (n = 35) for larval heartworm stages one larvae was encountered in an ethanol-fixated seal louse. During a health monitoring survey of live harbour seals, 109 animals were captured and examined during spring and autumn between 2008 and 2014. Blood samples were taken and microfilariae were discovered in blood smears in 41% (n = 45) of the examined harbour seals. Yearling seals (n = 21) showed higher prevalence (86%) and level of infection with microfilariae than adults. Microfilariae were identified as A. spirocauda by sequencing the species-specific COI gene in 24 blood samples. The high prevalence of microfilariae of A. spirocauda in blood samples (41%) is in contrast to the low prevalence of mature infections/adult specimens in stranded seals (4.4%) investigated. Although rare parasites of seals, the recent increase in prevalence of heartworm and seal lice in stranded seals and the relatively high occurrence of microfilaria in the free-ranging population underscore the importance of further studies investigating the immunology of infections and their transmission pathways, as

  10. Mechanical seal having a single-piece, perforated mating ring

    Science.gov (United States)

    Khonsari, Michael M.; Somanchi, Anoop K.

    2007-08-07

    A mechanical seal (e.g., single mechanical seals, double mechanical seals, tandem mechanical seals, bellows, pusher mechanical seals, and all types of rotating and reciprocating machines) with reduced contact surface temperature, reduced contact surface wear, or increased life span. The mechanical seal comprises a rotating ring and a single-piece, perforated mating ring, which improves heat transfer by controllably channeling coolant flow through the single-piece mating ring such that the coolant is in substantially uniform thermal contact with a substantial portion of the interior surface area of the seal face, while maintaining the structural integrity of the mechanical seal and minimizing the potential for coolant flow interruptions to the seal face caused by debris or contaminants (e.g., small solids and trash) in the coolant.

  11. Cadmium Toxicity to Ringed Seals (Phoca hispida)

    DEFF Research Database (Denmark)

    Sonne, Christian; Dietz, R.; Riget, F. F.;

    as laboratory mammals. We have studied possible cadmium induced histopathological changes in the kidneys as well as a demineralisation of the skeletal system (DXA-scanning of lumbal vertebraes). No obvious cadmium induced toxic changes were found. Food composition and physiological adaptations may explain......Cadmium concentrations in kidneys from ringed seals (Phoca hispida) from North West Greenland (Qaanaaq) are high. Concentrations range at level known to induce renal toxic effects (mainly tubulopathy) and demineralisation (osteopenia) of the skeletal system (Fanconi's Syndrome) in humans as well...

  12. Demographic histories and genetic diversities of Fennoscandian marine and landlocked ringed seal subspecies.

    Science.gov (United States)

    Nyman, Tommi; Valtonen, Mia; Aspi, Jouni; Ruokonen, Minna; Kunnasranta, Mervi; Palo, Jukka U

    2014-09-01

    Island populations are on average smaller, genetically less diverse, and at a higher risk to go extinct than mainland populations. Low genetic diversity may elevate extinction probability, but the genetic component of the risk can be affected by the mode of diversity loss, which, in turn, is connected to the demographic history of the population. Here, we examined the history of genetic erosion in three Fennoscandian ringed seal subspecies, of which one inhabits the Baltic Sea 'mainland' and two the 'aquatic islands' composed of Lake Saimaa in Finland and Lake Ladoga in Russia. Both lakes were colonized by marine seals after their formation c. 9500 years ago, but Lake Ladoga is larger and more contiguous than Lake Saimaa. All three populations suffered dramatic declines during the 20th century, but the bottleneck was particularly severe in Lake Saimaa. Data from 17 microsatellite loci and mitochondrial control-region sequences show that Saimaa ringed seals have lost most of the genetic diversity present in their Baltic ancestors, while the Ladoga population has experienced only minor reductions. Using Approximate Bayesian computing analyses, we show that the genetic uniformity of the Saimaa subspecies derives from an extended founder event and subsequent slow erosion, rather than from the recent bottleneck. This suggests that the population has persisted for nearly 10,000 years despite having low genetic variation. The relatively high diversity of the Ladoga population appears to result from a high number of initial colonizers and a high post-colonization population size, but possibly also by a shorter isolation period and/or occasional gene flow from the Baltic Sea.

  13. Vacuum Packaging of MEMS With Multiple Internal Seal Rings

    Science.gov (United States)

    Hayworth, Ken; Yee, Karl; Shcheglov, Kirill; Bae, Youngsam; Wiberg, Dean; Peay, Chris; Challoner, Anthony

    2008-01-01

    A proposed method of design and fabrication of vacuum-packaged microelectromechanical systems (MEMS) and of individual microelectromechanical devices involves the use of multiple internal seal rings (MISRs) in conjunction with vias (through holes plated with metal for electrical contacts). The proposed method is compatible with mass production in a wafer-level fabrication process, in which the dozens of MEMS or individual microelectromechanical devices on a typical wafer are simultaneously vacuum packaged by bonding a capping wafer before the devices are singulated (cut apart by use of a dicing saw). In addition to being compatible with mass production, the proposed method would eliminate the need for some complex and expensive production steps and would yield more reliable vacuum seals. Conventionally, each MEMS or individual microelectromechanical device is fabricated as one of many identical units on a device wafer. Vacuum packaging is accomplished by bonding the device wafer to a capping wafer with metal seal rings (one ring surrounding each unit) that have been formed on the capping wafer. The electrical leads of each unit are laid out on what would otherwise be a flat surface of the device wafer, against which the seal ring is to be pressed for sealing. The resulting pattern of metal lines and their insulating oxide coverings presents a very rough and uneven surface, upon which it is difficult to pattern the sealing metal. Consequently, the seal is prone to leakage unless additional costly and complex planarization steps are performed before patterning the seal ring and bonding the wafers.

  14. Could seals prevent cod recovery in the Baltic Sea?

    DEFF Research Database (Denmark)

    MacKenzie, Brian; Eero, Margit; Ojaveer, Henn

    2011-01-01

    Fish populations are increasingly affected by multiple human and natural impacts including exploitation, eutrophication, habitat alteration and climate change. As a result many collapsed populations may have to recover in ecosystems whose structure and functioning differ from those in which...... in an ecosystem that likely will change due to both the already started recovery of a cod predator, the grey seal Halichoerus grypus, and projected climate impacts. Simulation modelling, assuming increased seal predation, fishing levels consistent with management plan targets and stable salinity, shows...... these goals will also depend on how climate change affects cod recruitment....

  15. Status of grey seals along mainland Europe from the Southwestern Baltic to France

    Directory of Open Access Journals (Sweden)

    Tero Härkönen

    2007-01-01

    Full Text Available The grey seal was a common species along mainland Europe during the Stone Age (8,000-5,500 BC. Along the North Sea coast populations started to decline substantially during the 11th century as a result of excessive hunting. The last breeding populations disappeared in the 16th century in the Wadden Sea, and before 1900 in the Kattegat-Skagerrak and the Southwestern Baltic as a result of an extermination campaign. No regular pupping occurred along mainland Europe until the end of the 1970s, when a breeding colony was established near Amrum in the German Wadden Sea. Somewhat later, additional breeding sites were discovered near Terschelling in the Dutch Wadden Sea (1980, at Helgoland, and off Brittany in France. Tracking of movements indicate these seal groups to be linked to the larger populations in the UK. Numbers of grey seals in the recolonised areas have increased over the years, but in the Kattegat-Skagerrak stable numbersof about 25 individuals have been observed since the 1970s, whereas more than 100 grey seals are found in the Southwestern Baltic. In the southeastern North Sea, 120 grey seals occur during moult at Helgoland, 120 in the German and over 1,130 in the Dutch parts of the Wadden Sea in 2004. Along the southern Dutch and Belgian coasts small groups are regularly observed, but no colonies have yet been established. In the colonies off Brittany in France about 105 grey seals have been counted. Successful pupping has only been recorded 3 times in the Kattegat-Skagerrak over the past 30 years, and 2-4 pups are born annually in France and the Southwestern Baltic. The relative strongholds for breeding along the European continent are the Dutch Wadden Sea, where in 2003/2004 at least 150 pups were recorded, Amrum in the German Wadden Sea (23 pups and Helgoland (8 pups. Consequently, total numbers of counted grey seals from the Southwestern Baltic to France amounted to at least 1,600 in 2004, while about 190 pups were born in the area.

  16. Catch history of ringed seals (Phoca hispida in Canada

    Directory of Open Access Journals (Sweden)

    Randall R Reeves

    1998-06-01

    Full Text Available The ringed seal (Phoca hispida has always been a staple in the diet and household economy of Inuit in Canada. The present paper was prepared at the request of the NAMMCO Scientific Committee to support their assessment of ringed seal stocks in the North Atlantic Basin and adjacent arctic and subarctic waters. Specifically, our objective was to evaluate recent and current levels of use of ringed seals by Canadian Inuit. Annual removals probably were highest (possibly greater than 100,000 in the 1960s and 1970s, a period when sealskin prices were particularly strong. Catches declined substantially in the 1980s following a collapse in sealskin prices, presumably related to the European trade ban on skins from newborn harp and hooded seals (Phoca groenlandica and Cystophora cristata, respectively. Recent catch levels throughout Canada (1980s and early 1990s are believed to be in the order of 50,000 to 65,000 ringed seals, with a total average annual kill (including hunting loss in the high tens of thousands. No reliable system is in place to monitor catches of ringed seals, so any estimate must be derived from a heterogeneous array of sources.

  17. The ringed seal (Phoca hispida in the western Russian Arctic

    Directory of Open Access Journals (Sweden)

    Stanislav E Belikov

    1998-06-01

    Full Text Available This paper presents a review of available published and unpublished material on the ringed seal (Phoca hispida in the western part of the Russian Arctic, including the White, Barents and Kara seas. The purpose of the review is to discuss the status of ringed seal stocks in relation to their primary habitat, the history of sealing, and a recent harvest of the species in the region. The known primary breeding habitats for this species are in the White Sea, the south-western part of the Barents Sea, and in the coastal waters of the Kara Sea, which are seasonally covered by shore-fast ice. The main sealing sites are situated in the same areas. Female ringed seals become mature by the age of 6, and males by the age of 7. In March-April a female gives birth to one pup in a breeding lair constructed in the shore-fast ice. The most important prey species for ringed seals in the western sector of the Russian Arctic are pelagic fish and crustaceans. The maximum annual sealing level for the region was registered in the first 70 years of the 20th century: the White Sea maximum (8,912 animals was registered in 1912; the Barents Sea maximum (13,517 animals was registered in 1962; the Kara Sea maximum (13,200 animals was registered in 1933. Since the 1970s, the number of seals harvested has decreased considerably. There are no data available for the number of seals harvested annually by local residents for their subsistence.

  18. Emergence of the Zoonotic Biliary Trematode Pseudamphistomum truncatum in Grey Seals (Halichoerus grypus) in the Baltic Sea

    Science.gov (United States)

    Bergman, Anders; Bignert, Anders; Höglund, Johan; Lundström, Karl; Strömberg, Annika; Bäcklin, Britt-Marie

    2016-01-01

    The biliary trematode Pseudamphistomum truncatum parasitizes a wide range of fish-eating mammals, including humans. Here we report the emergence of this parasite in grey seals (Halichoerus grypus) in the Baltic Sea. One hundred eighty-three of 1 554 grey seals (11.9%) examined from 2002–2013 had detectable hepatobiliary trematode infection. Parasite identification was confirmed as P. truncatum by sequencing the ITS2 region of a pool of five to 10 trematodes from each of ten seals collected off the coast of seven different Swedish counties. The proportion of seals parasitized by P. truncatum increased significantly over time and with increasing age of seals. Males were 3.1 times more likely to be parasitized than females and animals killed in fishery interactions were less likely to be parasitized than animals found dead or hunted. There was no significant difference in parasitism of seals examined from the Gulf of Bothnia versus those examined from the Baltic Proper. Although the majority of infections were mild, P. truncatum can cause severe hepatobiliary disease and resulted in liver failure in at least one seal. Because cyprinid fish are the second intermediate host for opisthorchiid trematodes, diets of grey seals from the Baltic Sea were analysed regarding presence of cyprinids. The proportion of gastrointestinal tracts containing cyprinid remains was ten times higher in seals examined from 2008 to 2013 (12.2%) than those examined from 2002 to 2007 (1.2%) and coincided with a general increase of trematode parasitism in the host population. The emergence and relatively common occurrence of P. truncatum in grey seals signals the presence of this parasite in the Baltic Sea ecosystem and demonstrates how aquatic mammals can serve as excellent sentinels of marine ecosystem change. Investigation of drivers behind P. truncatum emergence and infection risk for other mammals, including humans, is highly warranted. PMID:27755567

  19. Mathematical Model of Piston Ring Sealing in Combustion Engine

    Directory of Open Access Journals (Sweden)

    Koszałka Grzegorz

    2015-01-01

    Full Text Available This paper presents a mathematical model of piston-rings-cylinder sealing (TPC of a combustion engine. The developed model is an itegrated model of gas flow through gaps in TPC unit, displacements and twisting motions of piston rings in ring grooves as well as generation of oil film between ring face surfaces and cylinder liner. Thermal deformations and wear of TPC unit elements as well as heat exchange between flowing gas and surrounding walls, were taken into account in the model. The paper contains descriptions of: assumptions used for developing the model, the model itself, its numerical solution as well as its computer application for carrying out simulation tests.

  20. Mathematical Model of Piston Ring Sealing in Combustion Engine

    OpenAIRE

    Koszałka Grzegorz; Guzik Mirosław

    2015-01-01

    This paper presents a mathematical model of piston-rings-cylinder sealing (TPC) of a combustion engine. The developed model is an itegrated model of gas flow through gaps in TPC unit, displacements and twisting motions of piston rings in ring grooves as well as generation of oil film between ring face surfaces and cylinder liner. Thermal deformations and wear of TPC unit elements as well as heat exchange between flowing gas and surrounding walls, were taken into account in the model. The pape...

  1. Replacement of nickel sealing rings by expanded graphite sealing rings -upgrading of SG primary collector flange connection

    Energy Technology Data Exchange (ETDEWEB)

    Cikryt, F.; Bednarek, L.; Kusyn, L. [Vitkovice, Ostrava (Switzerland)

    1997-12-31

    One of the most loaded parts of a steam generator of VVER 440 MW type are the bolts and thread holes of the primary collector cover sealing set. The strength calculations and tensometric measurings performed during operation proved the high degree of a load on the bolts. The conditions of the stress limitation are not met in some cases according to the pertinent standards. The untightnesses at nickel rings occurred during putting the units of Jaslovske Bohunice and Dukovany nuclear power stations into operation. With regard to improve the reliability, the producer has taken measures to improve the quality of the rings and users have introduced more strict regulations for bolts tightening. Due to these measures the high reliability of the set has been obtained from point of view of the tightness, but substantial reduction of bolts and holes threads loading have not been obtained. Several years operation experience proved relatively low service of bolts, damage of thread holes and sealing grooves. As the degree of mechanical load is one of the vital parameters influencing the damage of sealing set, in 1996 we started with the works aimed at a possibility of nickel sealing rings replacement for a more modern type of sealing which assure the higher reliability and service life of the individual part of sealing set under the reduced load.

  2. Impaired immune function in seals and laboratory rats exposed to dioxin-like compounds from Baltic herring

    Energy Technology Data Exchange (ETDEWEB)

    Ross, P.S. [Seal Rehabilitation and Research Centre, Pieterburen (Netherlands)]|[National Inst. of Public Health and Environmental Protection, Bilthoven (Netherlands); Swart, R.L. de [Seal Rehabilitation and Research Centre, Pieterburen (Netherlands)]|[Erasmus Univ., Rotterdam (Netherlands); Timmerman, H.H.; Loveren, H. van [National Inst. of Public Health and Environmental Protection, Bilthoven (Netherlands); Osterhaus, A.D.M.E. [Seal Rehabilitation and Research Centre, Pieterburen (Netherlands)]|[National Inst. of Public Health and Environmental Protection, Bilthoven (Netherlands)]|[Erasmus Univ., Rotterdam (Netherlands)

    1995-12-31

    Complex mixtures of lipophilic contaminants have been shown to affect certain top predators in the aquatic food chain, including seals. A recent demonstration that harbor seals (Phoca vitulina) fed Baltic Sea herring displayed impaired natural killer cell activity and T-lymphocyte function represented the first demonstration of immunotoxicity induced by ambient levels of contaminants in the environment. While these animals had a lower ability to respond to immunizations with inactivated vaccines, specific antibody responses, and in vitro antigen-specific lymphoproliferative responses, obvious constraints limited the ability to extend these results with host resistance tests or an evaluation of thymus and other lymphoid organs. The authors therefore set up a parallel study by exposing pregnant laboratory rats to the same Baltic herring contaminant mixture as received the seals. They then examined immune function parameters and host resistance to virus infection. As in the seals, rat pups of the Baltic group had impaired T-lymphocyte function. In addition, thymus cells and/or their precursors appeared to be targeted, as their numbers and function were reduced in the rats. Following challenge with rat cytomegalovirus in a host resistance study, rat pups in the Baltic group had impaired natural killer cell responses to the virus infection, and lower specific CD8 + (cytotoxic T-lymphocyte) responses following in vitro stimulation. By extrapolation, these results suggest that the impaired immune responses observed in the Baltic group of seals may lead to a less effective defense against virus infections in marine mammals inhabiting polluted coastal waters. Toxicological profiles and results of both the captive seal and laboratory rat experiments tend to implicate the 2,3,7,8-TCDD-like PCB, dioxin and furan congeners in the immunosuppression, and point to a major role for the PCBs.

  3. Oil Leakage from the Seal Ring of a Scroll Compressor

    Science.gov (United States)

    Kobayashi, Naoki; Fukui, Atsushi; Horiguchi, Hironori; Tsujimoto, Yoshinobu; Toyama, Toshiyuki

    In scroll compressors for air conditioners, there is a compressor with back-pressure chamber spaced by seal ring behind orbiting scroll. High pressure in the backpressure chamber presses the orbiting scroll to fixed scroll. In the case that lubrication oil and refrigerant gas with high pressure and temperature in the backpressure chamber leak to low pressure chamber through the seal ring, the efficiency of compressor decreases and the oil circulation rate can increase. In the present study the leakage characteristics of lubrication oil from the backpressure chamber to the low pressure chamber were investigated. In experiment, it was found that the oil leakage is larger for higher rotational speed of rotating disk, higher viscosity of oil and smaller pressure difference between the backpressure and low-pressure chambers. This could be explained by the calculation in which the seal ring was assumed to have a tilt angle. It was also found in the calculation that oil leakage is larger due to the thicker oil film between the seal ring and the rotating disk in the case of higher rotational speed of the disk, higher viscosity of oil and smaller pressure difference between the backpressure and low-pressure chambers.

  4. O-Ring sealing arrangements for ultra-high vacuum systems

    Science.gov (United States)

    Kim, Chang-Kyo; Flaherty, Robert

    1981-01-01

    An all metal reusable O-ring sealing arrangement for sealing two concentric tubes in an ultra-high vacuum system. An O-ring of a heat recoverable alloy such as Nitinol is concentrically positioned between protruding sealing rings of the concentric tubes. The O-ring is installed between the tubes while in a stressed martensitic state and is made to undergo a thermally induced transformation to an austenitic state. During the transformation the O-ring expands outwardly and contracts inwardly toward a previously sized austenitic configuration, thereby sealing against the protruding sealing rings of the concentric tubes.

  5. Antifungal Sealing Rings - A New Approach

    Science.gov (United States)

    1977-10-01

    standard conditions (19,20). The properties of the O-rings were determined on an Instron Model 1026 tensometer using a motorised specimen holder drive unit...dismantled for modi- fication or servicing, adhesive strength between rubber and substrate should 4 bý. weak- All these factor& were assessed as part of...Marine Coatings. Part II: Marine Biocidal Rubbers Containing Organotin Toxics. M.R.L. Report 496. 13. - . (1963). Vulcanized Polychloroprene Rubbers for

  6. Multiple internal seal ring micro-electro-mechanical system vacuum packaging method

    Science.gov (United States)

    Hayworth, Ken J. (Inventor); Yee, Karl Y. (Inventor); Shcheglov, Kirill V. (Inventor); Bae, Youngsam (Inventor); Wiberg, Dean V. (Inventor); Challoner, A. Dorian (Inventor); Peay, Chris S. (Inventor)

    2008-01-01

    A Multiple Internal Seal Ring (MISR) Micro-Electro-Mechanical System (MEMS) vacuum packaging method that hermetically seals MEMS devices using MISR. The method bonds a capping plate having metal seal rings to a base plate having metal seal rings by wafer bonding the capping plate wafer to the base plate wafer. Bulk electrodes may be used to provide conductive paths between the seal rings on the base plate and the capping plate. All seals are made using only metal-to-metal seal rings deposited on the polished surfaces of the base plate and capping plate wafers. However, multiple electrical feed-through metal traces are provided by fabricating via holes through the capping plate for electrical connection from the outside of the package through the via-holes to the inside of the package. Each metal seal ring serves the dual purposes of hermetic sealing and providing the electrical feed-through metal trace.

  7. Influence analysis of secondary O-ring seals in dynamic behavior of spiral groove gas face seals

    Science.gov (United States)

    Hu, Songtao; Huang, Weifeng; Liu, Xiangfeng; Wang, Yuming

    2016-05-01

    The current research on secondary O-ring seals used in mechanical seals has begun to focus on their dynamic properties. However, detailed analysis of the dynamic properties of O-ring seals in spiral groove gas face seals is lacking. In particular a transient study and a difference analysis of steady-state and transient performance are imperative. In this paper, a case study is performed to gauge the effect of secondary O-ring seals on the dynamic behavior (steady-state performance and transient performance) of face seals. A numerical finite element method (FEM) model is developed for the dynamic analysis of spiral groove gas face seals with a flexibly mounted stator in the axial and angular modes. The rotor tilt angle, static stator tilt angle and O-ring damping are selected to investigate the effect of O-ring seals on face seals during stable running operation. The results show that the angular factor can be ignored to save time in the simulation under small damping or undamped conditions. However, large O-ring damping has an enormous effect on the angular phase difference of mated rings, affecting the steady-state performance of face seals and largely increasing the possibility of face contact that reduces the service life of face seals. A pressure drop fluctuation is carried out to analyze the effect of O-ring seals on the transient performance of face seals. The results show that face seals could remain stable without support stiffness and O-ring damping during normal stable operation but may enter a large-leakage state when confronting instantaneous fluctuations. The oscillation-amplitude shortening effect of O-ring damping on the axial mode is much greater than that on the angular modes and O-ring damping prefers to cater for axial motion at the cost of angular motion. This research proposes a detailed dynamic-property study of O-ring seals in spiral groove gas face seals, to assist in the design of face seals.

  8. Wafer-level packaging with compression-controlled seal ring bonding

    Science.gov (United States)

    Farino, Anthony J

    2013-11-05

    A device may be provided in a sealed package by aligning a seal ring provided on a first surface of a first semiconductor wafer in opposing relationship with a seal ring that is provided on a second surface of a second semiconductor wafer and surrounds a portion of the second wafer that contains the device. Forcible movement of the first and second wafer surfaces toward one another compresses the first and second seal rings against one another. A physical barrier against the movement, other than the first and second seal rings, is provided between the first and second wafer surfaces.

  9. Cadmium toxicity to ringed seals (Phoca hispida): an epidemiological study of possible cadmium-induced nephropathy and osteodystrophy in ringed seals (Phoca hispida) from Qaanaaq in Northwest Greenland

    DEFF Research Database (Denmark)

    Sonne-Hansen, C; Dietz, R; Leifsson, P S

    2002-01-01

    or osteodystrophy. This might be explained by the composition of the ringed seals diet, which contains high levels of vitamin D, calcium, phosphorus, zinc, selenium and protein. These elements are all likely to counteract cadmium-induced damage. It is speculated that ringed seal are not particularly vulnerable...

  10. Storage life of silicone rubber sealing ring used in solid rocket motor

    Institute of Scientific and Technical Information of China (English)

    Liu Weikai; He Guoqiang

    2014-01-01

    It is urgent to carry out detailed research on storage performance of rubber sealing ring to get the criterion for its storage life. This paper acquires material ageing regularity by theoretical analysis and experimental confirmation. On this condition, failure mode and failure criterion of typ-ical sealing structure is studied, and the failure mechanism is found. Thus by analyzing the stress distribution, the relationship between ageing state and sealing condition is established. Rationaliza-tion proposal is put forward and storage life of sealing ring is evaluated. The research mentioned-above has special reference to the design of sealing structures and can provide reference for prolong-ing their service life.

  11. Distribution, abundance and biology of ringed seals (Phoca hispida: an overview

    Directory of Open Access Journals (Sweden)

    Randall R Reeves

    1998-06-01

    potential impacts of industrial activity and pollution on ringed seals, such impacts have been documented only in limited areas. Because of their ubiquitous occurrence and availability for sampling, ringed seals are good subjects for monitoring contaminant trends in Arctic marine food chains.

  12. In-air evoked potential audiometry of grey seals (Halichoerus grypus) from the North and Baltic Seas.

    Science.gov (United States)

    Ruser, Andreas; Dähne, Michael; Sundermeyer, Janne; Lucke, Klaus; Houser, Dorian S; Finneran, James J; Driver, Jörg; Pawliczka, Iwona; Rosenberger, Tanja; Siebert, Ursula

    2014-01-01

    In-air anthropogenic sound has the potential to affect grey seal (Halichoerus grypus) behaviour and interfere with acoustic communication. In this study, a new method was used to deliver acoustic signals to grey seals as part of an in-air hearing assessment. Using in-ear headphones with adapted ear inserts allowed for the measurement of auditory brainstem responses (ABR) on sedated grey seals exposed to 5-cycle (2-1-2) tone pips. Thresholds were measured at 10 frequencies between 1-20 kHz. Measurements were made using subcutaneous electrodes on wild seals from the Baltic and North Seas. Thresholds were determined by both visual and statistical approaches (single point F-test) and good agreement was obtained between the results using both methods. The mean auditory thresholds were ≤40 dB re 20 µPa peak equivalent sound pressure level (peSPL) between 4-20 kHz and showed similar patterns to in-air behavioural hearing tests of other phocid seals between 3 and 20 kHz. Below 3 kHz, a steep reduction in hearing sensitivity was observed, which differed from the rate of decline in sensitivity obtained in behavioural studies on other phocids. Differences in the rate of decline may reflect influence of the ear inserts on the ability to reliably transmit lower frequencies or interference from the structure of the distal end of the ear canal.

  13. Netting and conventional tagging used to study movements of ringed seals (Phoca hispida in Greenland

    Directory of Open Access Journals (Sweden)

    Finn O Kapel

    2014-05-01

    Full Text Available Seven studies of netting and tagging of ringed seals (Phoca hispida in Greenland 1976-1997 are described. The areas of operation were: northern part of the Upernavik area (Northwest Greenland, Kong Oscars Fjord (Northeast Greenland, and Avanersuaq (Thule, North Greenland. Altogether, 135 seals were caught, of which 99 were tagged and released with Dalton Jumbo rototags. Recapture of 38 tagged seals has been reported to date. The recaptures demonstrate movements of ringed seals in Greenland of more than 100km within districts, as well as long-distance movementsof more than 1000km from the site of release.

  14. Mercury and cadmium in ringed seals in the Canadian Arctic: Influence of location and diet

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Tanya M., E-mail: tanya.brown@mun.ca [Memorial University of Newfoundland, St. John' s, Newfoundland A1B 3X9 (Canada); Fisk, Aaron T. [Great Lakes Institute of Environmental Research, University of Windsor, 401 Sunset Avenue, Windsor, Ontario N9B 3P4 (Canada); Wang, Xiaowa [Environment Canada, Canada Centre for Inland Waters, 867 Lakeshore Road, Burlington, Ontario L7R 4A6 (Canada); Ferguson, Steven H. [Fisheries and Oceans Canada, 501 University Crescent, Winnipeg, Manitoba R3T 2N6 (Canada); Young, Brent G. [University of Manitoba, 500 University Crescent, Winnipeg, Manitoba R3T 2N2 (Canada); Reimer, Ken J. [Environmental Sciences Group, Royal Military College of Canada, PO Box 17000, Stn Forces, Kingston, Ontario K7K 7B4 (Canada); Muir, Derek C.G. [Environment Canada, Canada Centre for Inland Waters, 867 Lakeshore Road, Burlington, Ontario L7R 4A6 (Canada)

    2016-03-01

    Concentrations of total mercury (THg) and total cadmium (TCd) were determined in muscle and liver of ringed seals (Pusa hispida) from up to 14 locations across the Canadian Arctic. Location, trophic position (TP) and relative carbon source best predicted the THg and TCd concentrations in ringed seals. THg concentrations in ringed seals were highest in the western Canadian Arctic (Beaufort Sea), whereas TCd was highest in the eastern Canadian Arctic (Hudson Bay and Labrador). A positive relationship between THg and TP and a negative relationship between THg and relative carbon source contributed to the geographical patterns observed and elevated THg levels at certain sites. In contrast, a negative relationship between TCd and TP was found, indicating that high TCd concentrations are related to seals feeding more on invertebrates than fish. Feeding ecology appears to play an important role in THg and TCd levels in ringed seals, with biomagnification driving elevated THg levels and a dependence on low-trophic position prey resulting in high TCd concentrations. The present study shows that both natural geological differences and diet variability among regions explain the spatial patterns for THg and TCd concentrations in ringed seals. - Highlights: • Diet and location influenced THg and Cd in ringed seals across the Canadian Arctic. • Biomagnification processes contribute to elevated THg levels in the western Arctic. • Consuming low-trophic position prey explains high Cd levels in the eastern Arctic.

  15. Cadmium toxicity to ringed seals (Phoca hispida): an epidemiological study of possible cadmium-induced nephropathy and osteodystrophy in ringed seals (Phoca hispida) from Qaanaaq in Northwest Greenland

    DEFF Research Database (Denmark)

    Sonne-Hansen, C; Dietz, R; Leifsson, P S;

    2002-01-01

    . Experience from cadmium-poisoned humans and laboratory mammals indicates that concentrations above 50-200 microg/g wet wt. may induce histopathological changes. Overall, 31 of the ringed seals had cadmium concentrations in the kidney cortex above 50 microg/g wet wt., 11 had concentrations above 100 and one......The Greenland marine food chains contain high levels of cadmium, mercury and selenium. Concentrations of cadmium in the kidney of ringed seals (Phoca hispida) from the municipalities of Qaanaaq and Upernavik (Northwest Greenland) are among the highest recorded in the Arctic. The purpose...... of the study was to determine whether cadmium-induced damage in the kidneys and the skeletal system could be detected among 100 ringed seals from Northwest Greenland. The cadmium concentrations in the kidney cortex ranged from 0 to 248 microg/g wet weight (mean=44.5, N=100) in the 99 kidneys examined...

  16. 76 FR 77466 - Endangered and Threatened Species; Proposed Threatened Status for Subspecies of the Ringed Seal

    Science.gov (United States)

    2011-12-13

    ..., primarily due to concerns about threats to their habitat from climate warming and loss of sea ice. The... expertise in seal biology and/or Arctic sea ice and climate change regarding the pertinent scientific data... posed to Arctic ringed seals by the projected changes in sea ice habitat, in particular on-ice...

  17. Split ring floating air riding seal for a turbine

    Energy Technology Data Exchange (ETDEWEB)

    Mills, Jacob A

    2015-11-03

    A floating air riding seal for a gas turbine engine with a rotor and a stator, an annular piston chamber with an axial moveable annular piston assembly within the annular piston chamber, an annular cavity formed on the annular piston assembly that faces a seal surface on the rotor, and a central passage connecting the annular cavity to the annular piston chamber to supply compressed air to the seal face, where the annular piston assembly is a split piston assembly to maintain a tight seal as coning of the rotor disk occurs.

  18. Fluid-solid interaction model for hydraulic reciprocating O-ring seals

    Science.gov (United States)

    Liao, Chuanjun; Huang, Weifeng; Wang, Yuming; Suo, Shuangfu; Liu, Ying

    2013-01-01

    Elastohydrodynamic lubrication characteristics of hydraulic reciprocating seals have significant effects on sealing and tribology performances of hydraulic actuators, especially in high parameter hydraulic systems. Only elastic deformations of hydraulic reciprocating seals were discussed, and hydrodynamic effects were neglected in many studies. The physical process of the fluid-solid interaction effect did not be clearly presented in the existing fluid-solid interaction models for hydraulic reciprocating O-ring seals, and few of these models had been simultaneously validated through experiments. By exploring the physical process of the fluid-solid interaction effect of the hydraulic reciprocating O-ring seal, a numerical fluid-solid interaction model consisting of fluid lubrication, contact mechanics, asperity contact and elastic deformation analyses is constructed with an iterative procedure. With the SRV friction and wear tester, the experiments are performed to investigate the elastohydrodynamic lubrication characteristics of the O-ring seal. The regularity of the friction coefficient varying with the speed of reciprocating motion is obtained in the mixed lubrication condition. The experimental result is used to validate the fluid-solid interaction model. Based on the model, The elastohydrodynamic lubrication characteristics of the hydraulic reciprocating O-ring seal are presented respectively in the dry friction, mixed lubrication and full film lubrication conditions, including of the contact pressure, film thickness, friction coefficient, liquid film pressure and viscous shear stress in the sealing zone. The proposed numerical fluid-solid interaction model can be effectively used to analyze the operation characteristics of the hydraulic reciprocating O-ring seal, and can also be widely used to study other hydraulic reciprocating seals.

  19. Small footprint wafer-level vacuum packaging using compressible gold sealing rings

    Science.gov (United States)

    Antelius, Mikael; Stemme, Göran; Niklaus, Frank

    2011-08-01

    A novel low-temperature wafer-level vacuum packaging process is presented. The process uses plastically deformed gold rings as sealing structures in combination with flux-free soldering to provide the bond force for a sealing wafer. This process enables the separation of the sealing and the bonding functions both spatially on the wafer and temporally in different process steps, which results in reduced areas for the sealing rings and prevents outgassing from the solder process in the cavity. This enables space savings and yields improvements. We show the experimental result of the hermetic sealing. The leak rate into the packages is determined, by measuring the package lid deformation over 10 months, to be lower than 3.5 × 10-13 mbar l s-1, which is suitable for most MEMS packages. The pressure inside the produced packages is measured to be lower than 10 mbar.

  20. Macroscopic Anatomy of the Saimaa Ringed Seal (Phoca hispida saimensis) Lower Respiratory Tract.

    Science.gov (United States)

    Laakkonen, Juha; Jernvall, Jukka

    2016-04-01

    We studied the macroscopic anatomy of the lower respiratory tract of the endangered Saimaa ringed seal (Phoca hispida saimensis). Examination of one adult and one young individual found dead showed that trachea had 85 and 86 complete cartilage rings. The adjacent cartilages exhibited very few random anastomoses. There was variation in the confirmation of the trachea between the cranial and caudal part of the trachea. The right lung was divided by partly incomplete inter-lobar fissures into cranial, middle, caudal, and accessory lobes. The left lung consisted of cranial, middle, and caudal lobes. The lungs were characterized by a high amount of interlobular connective tissue. Silicone casts were prepared of the two specimens to visualize the tracheobronchial branching which was similar to that of marine ringed seals but in the Saimaa ringed seal the right middle lobar bronchus originated at the same level as the accessory lobar bronchus.

  1. Cadmium toxicity to ringed seals (Phoca hispida): an epidemiological study of possible cadmium-induced nephropathy and osteodystrophy in ringed seals (Phoca hispida) from Qaanaaq in Northwest Greenland

    DEFF Research Database (Denmark)

    Sonne-Hansen, C; Dietz, R; Leifsson, P S;

    2002-01-01

    of the study was to determine whether cadmium-induced damage in the kidneys and the skeletal system could be detected among 100 ringed seals from Northwest Greenland. The cadmium concentrations in the kidney cortex ranged from 0 to 248 microg/g wet weight (mean=44.5, N=100) in the 99 kidneys examined...... to the proximal kidney tubules is known to induce demineralisation of the skeletal system (Fanconi's syndrome). Therefore, the three lowest lumbar vertebrae were scanned in 91 seals to measure the content of calcium. The 10 cases of nephropathy could neither be linked to the degree of mineralisation...

  2. Status of grey seals along mainland Europe from the Southwestern Baltic to France

    NARCIS (Netherlands)

    Härkönen, T.; Brasseur, S.M.J.M.; Teilmann, J.; Vincent, C.; Dietz, R.; Abt, K.; Reijnders, P.J.H.

    2007-01-01

    The grey seal was a common species along mainland Europe during the Stone Age (8,000-5,500 BC). Along the North Sea coast populations started to decline substantially during the 11th century as a result of excessive hunting. The last breeding populations disappeared in the 16th century in the Wadden

  3. Aging of Weapon Seals – An Update on Butyl O-ring Issues

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Mark H.

    2011-07-13

    During testing under the Enhanced Surveillance Campaign in 2001, preliminary data detected a previously unknown and potentially serious concern with recently procured butyl o-rings on several programs. All butyl o-rings molded from a proprietary formulation throughout the period circa 1999 through 2001 had less than a full cure. Engineering judgment was that under curing is detrimental and could possibly lead to sub-optimum performance or, in the worst case, premature seal failure. An aging study was undertaken to ensure that suspect o-rings installed in the stockpile will retain sufficient sealing force for a minimum ten-year service life. A new prediction model developed for this study indicates suspect o-rings do not need to be replaced before the ten-year service life. Long-term testing results are reported on a yearly basis to validate the prediction model. This report documents the aging results for the period September 2002 to January 2011.

  4. Radiocesium and polonium in seals from the Baltic Sea. A preliminary study; Radiocaesium och polonium i sael fran Oestersjoen, en preliminaer studie

    Energy Technology Data Exchange (ETDEWEB)

    Holm, E. [Risoe National Lab., Roskilde (Denmark); Leisvik, M. [Lunds Univ., Avd. foer Radiofysik, Lund (Sweden)

    2002-04-01

    {sup 137}Cs and {sup 210}Po in muscle, liver and kidney from 5 seals from the Baltic Sea have been studied. Assuming that the seals consume 5% of their own body weight each day and by using previously obtained data for the doses in fish, the biological half time has been estimated to 20 days for Cesium and 35 days for Polonium. The maximum yearly doses are calculated to 76 {mu}Gy from {sup 137}CS to muscle and 3 500 {mu}Gy to kidneys from {sup 210}Po. These data are very preliminary, the number of individuals being so small, and it is difficult to estimate how much food other than fish the seals consume. Furthermore only few data for radioactive concentrations in whole fish exist, which especially impacts the results for Polonium. (LN)

  5. The influence of climate variability on polar bear (Ursus maritimus) and ringed seal (Pusa hispida) population dynamics

    DEFF Research Database (Denmark)

    Rosing-Asvid, A.

    2006-01-01

    Unusually high polar bear (Ursus maritimus Phipps, 1774) predation on ringed seal (Pusa hispida (Schreber, 1775)) pups and increased survival of polar bear cubs during mild springs is documented in published articles. Strong predation on newborn ringed seal pups in early spring, however, is likely...... to lower the overall energy intake of polar bears if ringed seal pups are their main food, because the energetic value of ringed seal pups increases 7-8 times during the 6 week lactation period. So although hunting success in early spring increases cub survival during the period after den emergence......,when they are most vulnerable, it is likely to increase the number of starving bears later in the season. This negative-feedback effect of strong spring predation will not occur in areas where other seal species are abundant during summer, and polar bears in such areas are likely to exhibit population growth during...

  6. Macroscopic anatomy of the ringed seal [Pusa (Phoca) hispida] lower respiratory system.

    Science.gov (United States)

    Smodlaka, H; Henry, R W; Reed, R B

    2009-06-01

    This investigation serves to document the normal anatomical features of the lower respiratory tract of the ringed seal [Pusa (phoca) hispida]. Evaluation of embalmed specimens and tracheobronchial casts showed that the right lung of this seal consists of four lobes while the left has only three lobes. The ventral margins of the lungs do not reach the sternum causing them to form the boundary of the broad recessus costomediastinalis. Lung lobation corresponds with bronchial tree division. Pulmonary venous drainage includes right and left common veins draining ipsilateral cranial and middle lung lobes, and one common caudal vein draining both caudal lobes and the accessory lobe. The right and left pulmonary arteries divide into cranial and caudal branches at the level of the principal bronchus. The ringed seal has three tracheobronchial lymph nodes. The trachea has an average of 87 cartilages that exhibit a pattern of random anastomoses between adjacent rings. The trachea exhibits to a small degree the dorsoventrally flattened pattern that is described in other pinnipeds. The tracheal diameter is smaller than that of the canine.

  7. Spatial and temporal trends in perfluoroalkyl substances (PFASs) in ringed seals (Pusa hispida) from Svalbard.

    Science.gov (United States)

    Routti, Heli; Gabrielsen, Geir Wing; Herzke, Dorte; Kovacs, Kit M; Lydersen, Christian

    2016-07-01

    This study investigates concentrations of perfluoroalkyl carboxylates (PFCAs), perfluoroalkyl sulfonates (PFSAs) and perfluoroalkane sulfonamides (FASA) in plasma from ringed seals sampled in the period 1990-2010 (n = 71) in Svalbard, Norway. Perfluorooctane sulfonate was dominant among the perfluoroalkyl substances. PFCAs were dominated by perfluoroundecanoate followed by perfluorononanoate. C4C8 PFCAs and perfluorooctane sulfonamide (FOSA) were detected in ≤42% of the samples. PFSA and PFCA concentrations were higher in seals sampled from Kongsfjorden, a fjord influenced by strong inflows of Atlantic Water compared to seals from fjords dominated by Arctic Water (e.g. Billefjorden). Sex, age and body condition of the seals did not influence PFAS concentrations. Due to the confounding effect of year and sampling area, temporal trends were assessed only in seals sampled from Kongsfjorden (5 years, n = 51). PFHxS and PFOS concentrations did not show significant linear trends during the whole study period, but a decrease was observed since 2004. Concentrations of all of the detected PFCAs (C9C13 PFCAs) increased until 2004 after which they have declined or stabilized.

  8. AGING BEHAVIOR OF VITON O-RING SEALS IN THE 9975 SHIPPING PACKAGE

    Energy Technology Data Exchange (ETDEWEB)

    Skidmore, E.; Daugherty, W.; Hoffman, E.; Dunn, K.; Bellamy, S.

    2012-01-13

    The Savannah River Site (SRS) is storing plutonium (Pu) materials in the K-Area Materials Storage (KAMS) facility. The Pu materials were packaged according to the DOE-STD-3013 standard and shipped to the SRS in Type B 9975 packages. The robust 9975 shipping package was not designed for long-term product storage, but it is a specified part of the storage configuration and the KAMS facility safety basis credits the 9975 design with containment. Within the 9975 package, nested stainless steel containment vessels are closed with dual O-ring seals based on Viton{reg_sign} GLT or GLT-S fluoroelastomer. The aging behavior of the O-ring compounds is being studied to provide the facility with advanced notice of nonconformance and to develop life prediction models. A combination of field surveillance, leak testing of surrogate fixtures aged at bounding service temperatures, and accelerated-aging methodologies based on compression stress-relaxation and oxygen consumption analysis is being used to evaluate seal performance. A summary of the surveillance program relative to seal aging behavior is presented.

  9. Temporal Trends of Hexabromocyclododecane, Polybrominated Diphenyl Ethers and Polychlorinated Biphenyls in Ringed Seals from East Greenland

    DEFF Research Database (Denmark)

    Vorkamp, Katrin; Riget, Frank Farsø; Bossi, Rossana

    2011-01-01

    Concentrations of hexabromocyclododecane (HBCD) were determined in a combination of archived and fresh blubber samples of juvenile ringed seals from East Greenland collected between 1986 and 2008. R-HBCD was the only diastereoisomer consistently above levels of quantification and showed a signifi......Concentrations of hexabromocyclododecane (HBCD) were determined in a combination of archived and fresh blubber samples of juvenile ringed seals from East Greenland collected between 1986 and 2008. R-HBCD was the only diastereoisomer consistently above levels of quantification and showed...... a significant log-linear (exponential) increase from 2.0 to 8.7 ng/g lipid weight (median concentrations) with an annual rate of þ6.1%. The concentrations were up to several orders of magnitude lower than those reported for marine mammals from industrialized areas. Previously presented time trends...... on polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) have been extended with new data for 2006 and 2008. ΣPBDE in juvenile seals was the only parameter with a slight upward trend, however, dependent on the low 1986 concentration. Removing this data point resulted in a downward trend, which...

  10. Demographic, ecological, and physiological responses of ringed seals to an abrupt decline in sea ice availability

    Directory of Open Access Journals (Sweden)

    Steven H. Ferguson

    2017-02-01

    Full Text Available To assess whether demographic declines of Arctic species at the southern limit of their range will be gradual or punctuated, we compared large-scale environmental patterns including sea ice dynamics to ringed seal (Pusa hispida reproduction, body condition, recruitment, and stress in Hudson Bay from 2003 to 2013. Aerial surveys suggested a gradual decline in seal density from 1995 to 2013, with the lowest density occurring in 2013. Body condition decreased and stress (cortisol increased over time in relation to longer open water periods. The 2010 open water period in Hudson Bay coincided with extremes in large-scale atmospheric patterns (North Atlantic Oscillation, Arctic Oscillation, El Nino-Southern Oscillation resulting in the earliest spring breakup and the latest ice formation on record. The warming event was coincident with high stress level, low ovulation rate, low pregnancy rate, few pups in the Inuit harvest, and observations of sick seals. Results provide evidence of changes in the condition of Arctic marine mammals in relation to climate mediated sea ice dynamics. We conclude that although negative demographic responses of Hudson Bay seals are occurring gradually with diminishing sea ice, a recent episodic environmental event played a significant role in a punctuated population decline.

  11. Demographic, ecological, and physiological responses of ringed seals to an abrupt decline in sea ice availability

    Science.gov (United States)

    Young, Brent G.; Yurkowski, David J.; Anderson, Randi; Willing, Cornelia; Nielsen, Ole

    2017-01-01

    To assess whether demographic declines of Arctic species at the southern limit of their range will be gradual or punctuated, we compared large-scale environmental patterns including sea ice dynamics to ringed seal (Pusa hispida) reproduction, body condition, recruitment, and stress in Hudson Bay from 2003 to 2013. Aerial surveys suggested a gradual decline in seal density from 1995 to 2013, with the lowest density occurring in 2013. Body condition decreased and stress (cortisol) increased over time in relation to longer open water periods. The 2010 open water period in Hudson Bay coincided with extremes in large-scale atmospheric patterns (North Atlantic Oscillation, Arctic Oscillation, El Nino-Southern Oscillation) resulting in the earliest spring breakup and the latest ice formation on record. The warming event was coincident with high stress level, low ovulation rate, low pregnancy rate, few pups in the Inuit harvest, and observations of sick seals. Results provide evidence of changes in the condition of Arctic marine mammals in relation to climate mediated sea ice dynamics. We conclude that although negative demographic responses of Hudson Bay seals are occurring gradually with diminishing sea ice, a recent episodic environmental event played a significant role in a punctuated population decline. PMID:28168119

  12. Giardia duodenalis and Cryptosporidium spp. in the intestinal contents of ringed seals (Phoca hispida) and bearded seals (Erignathus barbatus) in Nunavik, Quebec, Canada

    Science.gov (United States)

    The prevalence in intestinal contents of ringed and bearded seals harvested for food in the Nunavik region of northern Quebec, Canada was determned for Giardia and Cryptosporidium genotypes and species. Specimens were analysed by dual color flow cytometry, immunofluorescence microscopy, and polymer...

  13. Cadmium, mercury, zinc and selenium in ringed seals (Phoca hispida from Greenland and Svalbard

    Directory of Open Access Journals (Sweden)

    Run Dietz

    1998-06-01

    Full Text Available Muscle, liver, and kidney tissue from 456 ringed seals (Phoca hispida from eight areas in Greenland were analysed for cadmium, mercury, zinc and selenium. In general, cadmium concentrations were high in liver and kidney tissue, with geometric means of 7.79 and 33.5 μg/g (all data on wet weight basis, respectively. Muscle levels were considerably lower, at 0.067 μg/g. The concentration of mercury was relatively high in liver tissue with a geometric mean of 2.59 μg/g. Muscle and kidney mercury levels were somewhat lower, with geometric means of 0.210 and 0.956 μg/g, respectively. Cadmium and mercury levels were strongly dependent upon age and sampling area, as well as the interaction combinations, indicating that the accumulation of cadmium and mercury varies with age and area. Mercury accumulated in all three tissues throughout life, whereas cadmium in liver and kidneys peaked in the age group 5-10 years old where after it dropped significantly. Cadmium levels showed a tendency towards higher concentrations in the northern municipalities, which may be due to the higher cadmium levels in certain prey items in the northern areas. Mercury levels were higher in seals from East Greenland compared to West Greenland. Variations in feeding habits probably explain some of the differences in levels of cadmium and mercury in ringed seals from different geographical areas. Cadmium concentrations were correlated (both pairwise and partial in the three organs. This was true for mercury as well, whereas only half of the combinations were significant for zinc and selenium. Cadmium was strongly correlated to mercury in all three tissues and zinc only in liver and kidneys. Mercury was only correlated to selenium in liver and not to zinc. High concentrations of cadmium were found in the bile from 58 ringed seals, and were about 10-fold higher than in muscle. The concentration of mercury in bile was relatively low, being only one third of the

  14. Overview and regional and temporal differences of heavy metals in Arctic whales and ringed seals in the Canadian Arctic.

    Science.gov (United States)

    Wagemann, R; Innes, S; Richard, P R

    1996-07-16

    Concentrations of mercury, cadmium, and other heavy metals in tissues of belugas (Delphinapterus leucas), narwhal (Monodon monoceros) and ringed seals (Phoca hispida) from across the Canadian Arctic are reported. Published and new information is used to provide an overview of metals in tissues of these animals, to delineate the existence of a spatial trend of mercury and cadmium in belugas and ringed seals, and to show a temporal trend is superimposed on the geochemical trend. Mercury concentrations in tissues of Arctic whales and ringed seals were high relative to the Canadian guideline of 0.5 micrograms/g wet wt., for mercury in fish, except in the skin of belugas (0.59-0.78 micrograms/g wet wt.) and flesh of ringed seals (0.39-0.41 micrograms/g wet wt.). In the flesh of belugas (0.94-1.34 micrograms/g wet wt.), and in the liver of ringed seals, tissues that are also consumed by Native people in the Arctic (8.34-27.5 micrograms/g wet wt.), the guideline value was significantly exceeded. Mean lead concentrations in tissues of belugas, narwhal and ringed seals were generally low (0.002-0.028 micrograms/g wet wt.), except in tissues of belugas in the St. Lawrence River (0.10-0.15 micrograms/g wet wt.). The concentration of zinc in the skin of whales was two to three times higher than in other tissues. The concentration of cadmium in organs was highest in narwhal. There was a positive correlation between mercury and selenium in the liver of all three species. The concentration of mercury in tissues of belugas and ringed seals was higher in the western than the eastern Arctic. This was attributed to different natural background concentrations in the western and eastern Arctic of Canada dictated by different geological formations in the two regions. Cadmium concentrations in tissues of belugas and ringed seals were higher in the eastern than the western Arctic. Zinc and copper in some tissues of belugas and ringed seals were also higher in the eastern than the western

  15. A modeling of pump impeller shroud and wear-ring seal as a whole, and its application to the pump rotordynamics

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Tae Woong [Kyungwon Univ., Sungnam (Korea, Republic of); Lee, An Sung [Korea Institute of Machinery and Materials, Taejon (Korea, Republic of)

    1998-06-01

    A modeling methodology of pump impeller shroud and wear-ring seal as a whole has been developed to give its rotordynamic coefficients. In this work the governing equations are derived for the continuous flow path of the impeller shroud and wear-ring seal. Pressure loss at the discontinuity of the connecting point between the impeller shroud and the wear-ring seal is defined by utilizing a pressure loss coefficient obtained from experimental measurements. The governing equations are solved directly by using the known conditions at the inlet of the impeller shroud and outlet of the wear-ring seal. A detailed rotordynamic analysis has been carried out on a 750 m-head fourteen-stage centrifugal pump system with the effects of the hydrodynamic forces of such as impeller shroud and wear-ring seals, balance piston, and interstage seals. Results have shown that the first critical speed obtained with all the seal effects is much higher than that obtained without those effects, and moreover that the system under consideration is unstable. Large cross coupled stiffness(k) of the impeller shroud and wear-ring seal has been suspected as the source of the problem. Design modifications of the impeller shroud and wear-ring seal geometry have been performed to decrease k and increase the direct damping(C). Finally, the design modifications have yielded a stable and well damped system.

  16. Aerial surveys of ringed seals (Phoca hispida) on fast and pack ice in the central Beaufort Sea of Alaska, 1985-1987 and 1996-1999 (NODC Accession 0000931)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These datasets include counts of ringed seals (Phoca hispida) and other marine mammals made during aerial surveys of ringed seals on fast and pack ice of the...

  17. A New Y-ring Based Seal Unit and Its Application to the Seal of Hydraulic Cylinder%一种新型Y形密封单元及其在液压油缸密封中的应用

    Institute of Scientific and Technical Information of China (English)

    唐金涛; 刘大炜; 乔永忠

    2011-01-01

    针对数控机床用液压平衡油缸密封单元的易损问题,对典型的密封单元失效模式进行总结,在分析一般O形圈及Y形圈密封原理的基础上,设计一种新型的Y形密封单元,并成功用于多台数控机床液压平衡油缸的维修和改造.实践证明新型Y形密封单元能大幅提高液压平衡油缸的密封性和寿命,并可应用于其他类型往复运动装置的密封.%Aimed at the abrasion problem of the seal component of the hydraulic cylinder acting as a counterbalance for CNC machine tools,the seal units' typical disable modes were summarized. Based on analyzing the seal principles of the common rubber sealing O-ring and Y-ring, a new Y-ring based seal unit was designed,and successfully applied in the alterations and maintenances of several CNC machine tools' counterbalance-used hydraulic cylinders. The practices prove that this new Y-ring based seal unit can efficiently increase the sealing effect and service life of the hydraulic cylinders, and it can be also used for the sealing of other reciprocating devices.

  18. Western Canadian Arctic ringed seal organic contaminant trends in relation to sea ice break-up.

    Science.gov (United States)

    Gaden, A; Ferguson, Steve H; Harwood, L; Melling, H; Alikamik, J; Stern, G A

    2012-04-17

    The association between changing sea ice conditions and contaminant exposure to Arctic animals interests Inuvialuit harvesters, communities, and researchers. We examined organochlorine contaminant (OC) concentrations in the blubber of 90 male adult ringed seals (Phoca hispida) sampled from the subsistence harvest in Ulukhaktok (formerly Holman), NT, Canada, just prior to break-up of the sea ice (1993-2008). OC blubber concentrations were assessed with respect to year and sea ice break-up date. HCB and age- and blubber-adjusted concentrations of p,p'-DDT and ΣCHB (chlorobornane) significantly decreased over the study period. With respect to the timing of the spring break-up, highly lipophlic OCs, such as p,p'-DDE and PCB 153, were higher during years of early ice clearing (at least 12 days earlier than the mean annual break-up date), whereas no trends were observed for α, β, and γ isomers of HCH, trans- and cis-chlordane, oxychlordane, or ΣCHB. The higher contaminant concentrations found in earlier break-up years is likely due to earlier and/or increased foraging opportunities. This situation also has potential for enhancing bioaccumulation and biomagnification of contaminants over the long-term if projected changes continue to result in lighter and earlier ice conditions.

  19. Non-contacting fluid ring seal systems for railcar axle bearing systems: Quarterly progress report No. 4, March 16-June 15, 1988

    Energy Technology Data Exchange (ETDEWEB)

    1988-06-01

    The main objectives of this DOE contract is the technical development of a practical, cost effective Fluid Ring seal system capable of: Drastically reducing locomotive drawbar traction power requirements by lowering seal friction losses prevalent in present railcar axle bearing systems; increasing reliability and safety of railroad cars by minimizing bearing lubricant leakage and minimizing bearing ''hot boxes''; and improving the productivity of the railway transportation systems by reducing rolling stock ''outages'' due to long seal life. Listed in this report are the seal test data.

  20. Study on Pressure Deformation of Mounted Carbon Seal Ring%镶装式石墨密封环的压力变形研究

    Institute of Scientific and Technical Information of China (English)

    张杰; 李鲲; 吴兆山; 丁思云; 李香; 郑国运

    2012-01-01

    采用有限元方法分析镶装式石墨密封环和整体石墨密封环的压力变形情况.结果表明:密封压力使石墨环密封端面产生负锥度变形,随着密封压力的增大,端面压力变形呈线性增加;镶装式结构能显著增加石墨环的整体强度和刚度,减小密封端面的压力变形,提高机械密封的可靠性.%The pressure deformation of mounted carbon seal ring and unitary carbon seal ring was studied using finite element analysis method. The results show that the deformation of sealing face formed by sealed pressure is negative conicity, and the pressure deformation increases linearly with the increase of seal pressure. The mounted structural element can enhance the strength and stiffness of seal ring effectively, reduce the pressure deformation of sealing face, and improve the mechanical seal reliability.

  1. Influencing Factors of Thermal Deformation on Hydrostatic Pressure Mechanical Seal and Optimization of Rotating and Stationary Rings

    Directory of Open Access Journals (Sweden)

    Lin Dong

    2013-02-01

    Full Text Available According to thermo-elastic deformation theory, take the temperature field analysis results of hydrostatic pressure mechanical seal as volume load to resolve the problem of thermal-structure coupling deformation of rotating and stationary rings in ANSYS software. The distribution laws of thermal strain, thermal stress and thermal-structure coupling deformation are obtained. The effects of working, material and structural parameters on axial, radial thermal deformation and deformation taper of the end faces are discussed in detail, and the main affecting factors are found out. Measures and structural constraint programs to control the thermal deformation are put forward. Base on the theory of thermal deformation compensation, the rotating and stationary rings are optimized, and the thermal deformation before and after their optimization are solved respectively and analyzed comparatively to verify the feasibility of the optimization program.

  2. Finite Element Analysis of the Combined Cone Slip-ring Sealing%锥形滑环组合密封有限元分析

    Institute of Scientific and Technical Information of China (English)

    文华斌; 胡勇; 唐克伦; 胡光忠; 郭毅

    2012-01-01

    采用ANSYS软件对锥形滑环组合密封进行有限元分析.分析了高压及超高压密封状态下动、静密封面的密封效果以及各密封部件的使用性能,解决了有限元分析过程中大应变问题和接触问题带来的收敛性差的技术难题和密封内压动态加载的技术难题.数值模拟结果表明,锥形滑环组合密封能够实现高压及超高压密封,且各密封部件工作状态良好.数值模拟工作为锥形滑环组合密封产品的开发提供了辅助.%The finite element analysis of the combined cone slip-ring sealing was done by ANSYS software. The sealing effect and the using performance of dynamic sealing surface and static sealing surface under high pressure and super high pressure were analyzed. The sealing technology problem of the dynamic pressure loading and the poor convergence technology problem caused by large strain and contact were solved. The simulation results show that the combined cone slip-ring sealing can satisfy the seal requirements of high pressure or super high pressure,and the working conditions of sealing parts are kept well. The numerical simulation offers helps for developing the combined cone slip-ring sealing.

  3. Non-contacting fluid ring seal systems for railcar axle bearing systems: Quarterly progress report No. 1, June 15 to September 15, 1987

    Energy Technology Data Exchange (ETDEWEB)

    1987-01-01

    The main objectives of this DOE contract is the technical development of a practical, cost effective Fluid Ring seal system capable of: Drastically reducing locomotive drawbar traction power requirements by lowering seal friction losses prevalent in present railcar axle bearing systems; increasing reliability and safety of railroad cars by minimizing bearing lubricant leakage and minimizing bearing ''hot boxes''; and improving the productivity of the railway transportation systems by reducing rolling stock ''outages'' due to long seal life. 14 refs.

  4. Butyl rubber O-ring seals: Revision of test procedures for stockpile materials

    Energy Technology Data Exchange (ETDEWEB)

    Domeier, L.A.; Wagter, K.R.

    1996-12-01

    Extensive testing showed little correlation between test slab and O-ring performance. New procedures, comparable to those used with the traditional test slabs, were defined for hardness, compression set, and tensile property testing on sacrificial O-ring specimens. Changes in target performance values were made as needed and were, in one case, tightened to reflect the O-ring performance data. An additional study was carried out on O-ring and slab performance vs cure cycle and showed little sensitivity of material performance to large changes in curing time. Aging and spectra of certain materials indicated that two sets of test slabs from current vendor were accidently made from EPDM rather than butyl rubber. Random testing found no O-rings made from EPDM. As a result, and additional spectroscope test will be added to the product acceptance procedures to verify the type of rubber compound used.

  5. An evaluation of teeth of ringed seals (Phoca hispida) from Greenland as a matrix to monitor spatial and temporal trends of mercury and stable isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Aubail, Aurore, E-mail: aaubail@yahoo.fr [National Environmental Research Institute, Aarhus University, Frederiksborgvej 399, P.O. Box 358, DK-4000 Roskilde (Denmark); Littoral, Environnement et Societes (LIENSs), UMR 6250, CNRS-Universite de La Rochelle, 2 rue Olympe de Gouges, F-17000 La Rochelle (France); Dietz, Rune; Riget, Frank [National Environmental Research Institute, Aarhus University, Frederiksborgvej 399, P.O. Box 358, DK-4000 Roskilde (Denmark); Simon-Bouhet, Benoit; Caurant, Florence [Littoral, Environnement et Societes (LIENSs), UMR 6250, CNRS-Universite de La Rochelle, 2 rue Olympe de Gouges, F-17000 La Rochelle (France)

    2010-10-01

    Total mercury (Hg) concentrations were measured in teeth of ringed seals from Qeqertarsuaq, central West Greenland (1982 to 2006) and Ittoqqortoormiit, central East Greenland (1986 to 2006). Stable isotopic ratios of carbon ({sup 13}C/{sup 12}C) and nitrogen ({sup 15}N/{sup 14}N) were determined as well to provide insights into diet variations between regions or through time. Mercury concentrations decreased the first years of life of the animals suggesting that Hg had been transferred from the mother to the foetus and newborn. The Hg concentrations in teeth were significantly lesser in ringed seals from central West Greenland compared to those from central East Greenland. Carbon and nitrogen stable isotopic values measured in the animals differed also significantly between the two regions. Increasing temporal trends of dental Hg concentrations between 1994 and 2006 were observed in ringed seals from both central West Greenland and central East Greenland. These increases were attributed to global changes in environmental Hg levels since no temporal trends in {delta}{sup 15}N values were found to support the hypothesis of a diet shift over time. Furthermore, a decreasing temporal trend in {delta}{sup 13}C values was observed in the teeth of seals from central East Greenland, and explained by a likely change over time towards more pelagic feeding habits; alternatively, the so-known Seuss effect was thought to be responsible for this decrease. Finally, it was concluded that the tooth of ringed seal was a good monitoring tissue to assess Hg trends.

  6. An evaluation of teeth of ringed seals (Phoca hispida) from Greenland as a matrix to monitor spatial and temporal trends of mercury and stable isotopes.

    Science.gov (United States)

    Aubail, Aurore; Dietz, Rune; Rigét, Frank; Simon-Bouhet, Benoît; Caurant, Florence

    2010-10-01

    Total mercury (Hg) concentrations were measured in teeth of ringed seals from Qeqertarsuaq, central West Greenland (1982 to 2006) and Ittoqqortoormiit, central East Greenland (1986 to 2006). Stable isotopic ratios of carbon ((13)C/(12)C) and nitrogen ((15)N/(14)N) were determined as well to provide insights into diet variations between regions or through time. Mercury concentrations decreased the first years of life of the animals suggesting that Hg had been transferred from the mother to the foetus and newborn. The Hg concentrations in teeth were significantly lesser in ringed seals from central West Greenland compared to those from central East Greenland. Carbon and nitrogen stable isotopic values measured in the animals differed also significantly between the two regions. Increasing temporal trends of dental Hg concentrations between 1994 and 2006 were observed in ringed seals from both central West Greenland and central East Greenland. These increases were attributed to global changes in environmental Hg levels since no temporal trends in delta(15)N values were found to support the hypothesis of a diet shift over time. Furthermore, a decreasing temporal trend in delta(13)C values was observed in the teeth of seals from central East Greenland, and explained by a likely change over time towards more pelagic feeding habits; alternatively, the so-known Seuss effect was thought to be responsible for this decrease. Finally, it was concluded that the tooth of ringed seal was a good monitoring tissue to assess Hg trends.

  7. Sealing Mechanism and Use of O-ring for Hydraulic Gear Pump%液压齿轮泵中O形圈密封机理和选用

    Institute of Scientific and Technical Information of China (English)

    周亚东

    2015-01-01

    该文对液压齿轮泵中的O形圈的密封机理进行了简要分析,并给出O形圈选用时的一些注意事项。%This article simple analysis sealing mechanism of O-ring which used in Hydraulic Gear Pump, and gives some notes of how to choose O-ring.

  8. Efficacy of antibacterial sealing gel and O-ring to prevent microleakage at the implant abutment interface: an in vitro study.

    Science.gov (United States)

    Nayak, Aishwarya Gajanan; Fernandes, Aquaviva; Kulkarni, Raghavendra; Ajantha, Ganavalli Subramanyam; Lekha, Krishnapillai; Nadiger, Ramesh

    2014-02-01

    Gaps and hollow spaces at the implant abutment interface will act as a bacterial reservoir that may cause peri-implantitis. Hence, the sealing ability of O-ring (in addition to polysiloxane) and GapSeal (an antibacterial sealing gel) was evaluated. A total of 45 identical implant systems (ADIN Dental Implant Systems) were divided into 3 groups of 15 implants each: an unsealed group, a group sealed with O-rings, and a group sealed with GapSeal gel. The implant and abutment were gamma sterilized after assembly. Two implants from each group were randomly incubated in sterile brain heart infusion (BHI) broth tubes and checked for sterility. The remaining 13 implants were incubated in BHI broth inoculated with Enterococcus and incubated for 5 days. They were then removed from the tubes, dried aseptically, placed in 2% sodium hypochlorite solution for 30 minutes, and washed with sterile saline for 5 minutes. Next, the assembly was dried aseptically and put in sterile BHI broth tubes and incubated for 24 hours to check surface sterility. Keeping 2 implants as controls from each group, the remaining 11 implants were dismantled group-wise and placed in liquid BHI broth; the test tubes were then shaken thoroughly so that the broth would come in contact with all implant surfaces. The solution from this tube was poured on pre-prepared sterile agar plates and incubated for 24 hours. The colonies formed on the agar plate were then counted using a digital colony counter. The data thus obtained were subjected to statistical analysis by Kruskal-Wallis analysis of variance and Mann-Whitney U test. It was concluded that though microbial growth is seen in all the 3 groups, the least growth was seen in the GapSeal group followed by the O-ring group.

  9. Ecological hypotheses for a historical reconstruction of upper trophic level biomass in the Baltic Sea and Skagerrak

    DEFF Research Database (Denmark)

    MacKenzie, Brian; Alheit, J.; Conley, D.J.;

    2002-01-01

    seals (Halichoerus grypus), ringed seals (Phoca hispida), harbour porpoises (Phocoena phocoena)) decreased. The relative roles of exploitation, marine mammal predation, and environmental variability (e.g., eutrophication, major inflows of saline water, climate change) on the long-term dynamics of key......Fish and marine mammal populations in the Baltic Sea and Skagerrak have undergone major fluctuations over the past five centuries. We summarize how these fluctuations may have depended on various forms of predation (e.g., cannibalism, fishing, hunting) and environmental processes. The best......- documented long-term fisheries in this region are the herring (Clupea harengus) fisheries near Bohuslan, western Sweden, and in the Oresund. These fisheries have been important since at least the 1200s and appear to be partly climatically driven. However, in the rest of the Baltic, information about...

  10. Lubrication and Sealing Analysis of Diesel Engine Piston Ring Pack%柴油机活塞环组密封润滑分析

    Institute of Scientific and Technical Information of China (English)

    邓志明; 朱海庆; 张红涛

    2011-01-01

    良好的密封和润滑是活塞环长期稳定运行的保障。在气密性仿真分析的基础上,建立了活塞环组的贫油润滑模型,提出了一种新的边界条件求解润滑模型。利用MATLAB仿真程序,完成了PA6—280柴油机活塞环组的密封与贫油润滑分析。结果发现,在密封性能良好的条件下,活塞环组处于一种非稳态的混合润滑状态,并且各个活塞环的润滑受先导环的润滑油供给情况影响很大。%Good sealing and lubrication ensures the piston ring to run stably for a long period On basis of sealing simulation and analysis, a poor lubrication model of piston ring group was established, where a new boundary condition was proposed solve the model. With MATLAB simulation program, the Sealing and poor lubrication analysis of PA6 - 280 diesel piston ring group was completed. It is found that piston ring group is on an unsteady state of mixed lubrication when it is in good sealing. Besides, the lubrication of all rings were greatly affected by oil supply of the leading ring.

  11. Sliding seal for mining machine power transmission

    Energy Technology Data Exchange (ETDEWEB)

    Levenstein, V.M.

    1993-07-06

    A generally tubular sealing mechanism is described for use in the power train of a mining machine to seal between an annular seal face on one of two spaced apart units in the power train and a sealing ring surface on the other of said units for sealed protection of a drive shaft connected between said two units, said sealing mechanism including a tubular seal carrier with a first end portion having a cylindrical sealing surface for being telescoped with said sealing ring surface, an annular seal element mountable on said cylindrical sealing surface for sealing engagement between said sealing ring surface and said cylindrical sealing surface, said carrier further having a second end portion with a radially extending face, a clamp connectable between said one unit and said carrier for urging said radially extending face toward said annular seal face, and a sealing member mountable in sealing engagement between said annular seal face and said radially extending face.

  12. Optimization Analysis of the Sealing Performance of Rectangular Sealing Ring of Automotive Brake Fluid Filling Gun%汽车制动液加注枪矩形密封圈性能的优化分析

    Institute of Scientific and Technical Information of China (English)

    张和平; 黄华坤

    2013-01-01

    利用有限元分析软件ANSYS,对汽车制动液加注枪与壶口的矩形密封圈的密封性能进行有限元分析.通过分析影响密封性的因素,如压缩率、摩擦因数、壶口内径、壶口壁厚,得到密封面接触压力随各因素变化的关系曲线.通过正交试验,确定各因素对密封面接触压力的贡献率,得到密封性能最优时各因素的取值.结果表明,压缩率对密封性的影响最大,其次是摩擦因数、壶口内径和壶口壁厚.%The sealing performance of the rectangular sealing ring between the automotive brake fluid filling gun and the spout of brake fluid pot was analyzed by using finite element analysis software ANSYS.By analyzing the factors influencing the sealing performance,such as compression rate,friction coefficient,the spout inner diameter and wall thickness,the variations of sealing surface contact pressure along with these factors were obtained.Through orthogonal experiments,the contribution rate of each factor on the sealing surface contact pressure was determined,and the optimal value of each factor was selected to get the best sealing performance.The results show that the influence of compression ratio on the sealing performance is the biggest,followed by friction coefficient,the spout inner diameter and wall thickness of brake fluid pot.

  13. Finite Element Analysis of Sealing Characteristics of the Rubber O-Ring for a Mechanical Seal%机械密封橡胶O形圈密封性能的有限元分析

    Institute of Scientific and Technical Information of China (English)

    陈志; 高钰; 董蓉; 吴波; 李建明

    2011-01-01

    采用含高阶项的Mooney-Rivlin本构模型对在机械密封沟槽中单侧受限丁腈橡胶O形圈的密封性能进行了数值计算,重点研究了预压缩率和介质压力对O形圈接触应力、接触宽度和峰值应力的影响。模拟计算结果表明:计算值与Lindley半经验公式值和Wendt实验值较为一致;O形圈预压缩率对主接触面上的接触应力分布有较大影响,而对受限侧接触面上的接触应力分布影响较小;预压缩率越大主接触面上峰值应力越大,而侧接触面上峰值应力基本不变;介质压力作用会对O形圈产生二次压缩,介质压力越大,主接触面和侧接触面上的峰值应力越大。被预压缩橡胶O形圈承受介质压力时,具有"自紧密封"特性,接触应力曲线具有抛物线特性;较小的O形圈预压缩率可以产生较大的接触应力。因此,建议机械密封O形圈的预压缩率不宜过大,以满足机械密封补偿环浮动性和端面追随性的要求。%The sealing characteristics of the nitrile rubber O-ring,restrained unilaterally in the seal groove of a mechanical seal,were numerically simulated using the Mooney-Rivlin model with high-order terms.Effects of the precompression ratio and the medium pressure on contact stress,contact width,and peak stress were mainly studied.Simulated results showed well agreement with the Lindley's semi-empirical relationship and the Wendt's experimental data.The contact stresses have a parabolic distribution along the main contact surface.The precompression ratio of the O-ring has a great effect on the main contact surface while an insignificant effect on the restrained contact surface.The greater the precompression ratio is,the larger the peak stress on the main contact surface is,whereas the peak stress on the restrained contact surface is almost unchanged.The so-called secondary compression of the O-ring results from the effect of medium pressure.The results also showed that the O-ring

  14. Non-contacting fluid ring seal systems for railcar axle bearing systems: Fifth quarterly report, June 16, 1988--September 15, 1988

    Energy Technology Data Exchange (ETDEWEB)

    1988-10-01

    During this fifth quarter the evaluation of D-size fluid ring sealed roller bearing assemblies was completed with the evaluation of seal configuration MT 3008 and 3016, 3016a and 3016b (different static contact seal concepts), when exposed to intensive dust and rain storms generated within an enclosure surrounding the nondriven side of test rig /number sign/3 over the entire speed range from 0 to 1220 RPM bearing test speed. During the test rig /number sign/3 shake down test runs it became apparent that the intensity of the dust and rain storms surrounding the fluid ring sealed bearing end within the ''mini'' climate chamber could be appropriately observed through small windows at 12:00 and 6:00 o'clock provided in the endwall of the ''mini-climate'' chamber, rig /number sign/3 was accordingly modified and the dust and rain exposure tests were conducted at numerous levels of severity. 6 figs.

  15. An evaluation of teeth of ringed seals (Phoca hispida) from Greenland as a matrix to monitor spatial and temporal trends of mercury and stable isotopes.

    OpenAIRE

    Aubail, Aurore; Dietz, Rune; Rigét, Frank; Simon-Bouhet, Benoit; Caurant, Florence

    2010-01-01

    International audience; Total mercury (Hg) concentrations were measured in teeth of ringed seals from Qeqertarsuaq, central West Greenland (1982 to 2006) and Ittoqqortoormiit, central East Greenland (1986 to 2006). Stable isotopic ratios of carbon (13C/12C) and nitrogen (15N/14N) were determined as well to provide insights into diet variations between regions or through time. Mercury concentrations decreased the first years of life of the animals suggesting that Hg had been transferred from t...

  16. A comparison of ringed and bearded seal diet, condition and productivity between historical (1975-1984) and recent (2003-2012) periods in the Alaskan Bering and Chukchi seas

    Science.gov (United States)

    Crawford, Justin A.; Quakenbush, Lori T.; Citta, John J.

    2015-08-01

    Reductions in summer sea ice in the Chukchi and Beaufort seas are expected to affect what has been an ice-adapted marine food web in the Pacific Arctic. To determine whether recent decreases in sea ice have affected ice-associated marine predators (i.e., ringed, Pusa hispida, and bearded seals, Erignathus barbatus) in the Bering and Chukchi seas we compared diet, body condition, growth, productivity, and the proportion of pups harvested (an index of weaning success) for seals of each species harvested by 11 Alaskan villages during two periods; a historical (1975-1984) and a recent period (2003-2012). We also examined how changes in indices of seal health may be correlated with the reduction of sea ice characteristic of the recent period. For ringed seals ⩾1 year of age, the % frequency of occurrence (%FO) of Arctic cod (Boreogadus saida), walleye pollock (Gadus chalcogramma), rainbow smelt (Osmerus mordax), and Pacific herring (Clupea pallasi) increased from the historic to the recent period, while the %FO of invertebrates decreased for both pups and seals ⩾1 year of age. For bearded seals ⩾1 year of age, the %FO of Arctic cod, pricklebacks, and flatfish increased during the recent period, while the %FO of saffron cod (Eleginus gracilis) decreased for pups. Although invertebrates did not change overall for either age class, decreases occurred in 10 of 24 specific prey categories, for bearded seals ⩾1 year of age; only echiurids increased. The %FO of gastropods and bivalves increased for pups while isopods and one species of shrimp and crab decreased in occurrence. During the recent period ringed seals grew faster, had thicker blubber, had no change in pregnancy rate, matured 2 years earlier, and a larger proportion of pups was harvested than during the historical period. Correlations with spring ice concentration showed that the growth and blubber thickness of seals ⩾1 year of age, blubber thickness of pups, and the proportion of pups in the harvest all

  17. Nato enlarging into the Baltic States

    Index Scriptorium Estoniae

    2003-01-01

    Prahas 21.-22. novembrini 2002 toimunud NATO tippkohtumisest ja seal vastu võetud otsusest Balti riikide alliansiga ühinemise kohta. Vt. samas: Russia's attitude to the NATO enlargement; Bush in Vilnius; Baltic states' prime ministers' met; Supporting USA?

  18. Research on Reliability of Shearer Ring Arms' Floating Seal%提高采煤机摇臂用浮动油封可靠性的研究

    Institute of Scientific and Technical Information of China (English)

    宋相坤; 瑞光; 周常飞

    2011-01-01

    由于浮动油封失效会导致工作面煤尘进入摇臂,造成行星结构损坏,影响生产效率。为解决这一问题,分析了影响采煤机摇臂用浮动油封使用寿命的因素,研制了浮动油封试验装置。通过对浮动油封进行相关试验,提出了改进浮动油封可靠性的措施。实践结果表明:延长了浮动油封的使用寿命。%In order to solve this problem,the factors that influence use life of shear ring arms' floating seal are analyzed.The floating seal experiment device is being researched.The improve methods of improving floating seal's reliability are proposed by relevant experiment.The practical results show that the use life of floating seal prolongs.

  19. Seals and sealing handbook

    CERN Document Server

    Flitney, Robert K

    2014-01-01

    Seals and Sealing Handbook, 6th Edition provides comprehensive coverage of sealing technology, bringing together information on all aspects of this area to enable you to make the right sealing choice. This includes detailed coverage on the seals applicable to static, rotary and reciprocating applications, the best materials to use in your sealing systems, and the legislature and regulations that may impact your sealing choices. Updated in line with current trends this updated reference provides the theory necessary for you to select the most appropriate seals for the job and with its 'Failur

  20. Sifat fisika dan analisis gugus fungsi karet seal o-ring dari bahan termoplastik elastomer nitrile butadiene rubber (NBR dan polyvinyl chloride (PVC

    Directory of Open Access Journals (Sweden)

    Arum Yuniari

    2013-06-01

    Full Text Available The purpose of this research was to determine the physical properties and functional groups on O-ring rubber seals made of thermoplastic elastomers blend NBR and PVC. Composition of the NBR / PVC were successively varied : 90/10; 85/15; 80/20; 75/25; 70/30 and 65/35 phr. Mixing process between NBR/PVC with additive used a two roll mill within a temperature of 60º - 80 ºC, the vulcanization process used a hydraulic press at a temperature of 170 oC and pressure of 150 kg/cm2. The physical properties were evaluated including tensile strength, elongation at break, hardness, before and after aging, hardness after immersion in isooctane and swelling while analysis of functional groups was also carried out by method of Fourier Transform Infrared Spectrophotometer (FTIR. The result of the best vulcanized was characterized by tensile strength 188.93 kg/cm2, the change of tensile strength after aging 2.50%, elongation at break of 400%, the change of elongation at break after aging was 12.5%, hardness 75 shore A, the change of hardness after aging 0%, the change of hardness after immersion in isooctane 1.3%, swelling 0.8% and functional group of vulcanisate was indicated by new peak (OH at wave band of 3468 cm-1. Those formula met the requirements of the technical specifications of ASTM D 2000 seal O-ring.

  1. Seal assembly with anti-rotation pin for high pressure supercritical fluids

    Science.gov (United States)

    Wright, Steven A.; Fuller, Robert L.

    2014-08-05

    A seal assembly for sealing a machine with a first chamber and a second chamber is provided. A rotating shaft extends through the first and second chambers, and rotates therein. The seal assembly has a seal housing, a seal ring and a seal pin. The seal housing is positionable in the machine housing. The seal housing has a seal pocket extending into a fluid side thereof, and a housing receptacle extending into an inner diameter thereof at the seal pocket. The seal ring is positionable in the seal pocket of the seal housing for forming a seal therewith. The seal ring has a ring receptacle extending into an outer diameter thereof. The ring receptacle is positionable adjacent to the housing receptacle for defining a pin hole therebetween. The seal pin is loosely positionable in the pin hole whereby movement about the seal ring is accommodated while preventing rotation thereof.

  2. An Experimental Study on the Friction States Identification of Seal Ring in Vehicle Transmission Device%车辆传动装置密封环摩擦状态辨识的试验研究

    Institute of Scientific and Technical Information of China (English)

    宫燃; 葛如海; 张学荣; 徐宜

    2013-01-01

    For exploring the cause of the premature failure of seal ring in vehicle transmission device and understanding the rule of transform in sealing friction states and its effects on sealing performance, the friction coefficient versus operating parameter curves, i. e. f-G curves are obtained by a measurement on a sealing performance test rig for transmission device, the changing rule of sealing friction states at different oil temperature conditions is studied, and the effects of friction state transform on sealing performance are analyzed. The results indicate that under the set test conditions, the transforming rule of friction states of seal ring and its identification features can be revealed by f-G curves; But the change of friction states of seal ring only has limited effects on seal leakage while the influences of the temperature rise of seal ring are more apparent.%为探讨车辆传动装置的密封环早期失效的原因,掌握密封摩擦状态转变规律及其对密封性能的影响,利用传动装置密封性能试验台,测得摩擦因数-工况参数曲线(即f-G曲线),研究了不同油温条件下密封摩擦状态的变化规律,分析了密封环摩擦状态转变对密封性能的影响.结果表明,在设定的试验条件下,通过f-G曲线可揭示密封环在高速重载工况下摩擦状态转变规律及其辨识特征;密封环摩擦状态的转变对泄漏量的影响有限,而对密封环温升的影响较为显著.

  3. 离合器分离轴承结构对密封圈压入力影响研究%Influence Research of the Clutch Hydraulic Release Bearing Cylinder 's Construction on the Pressing Force of Sealing Ring

    Institute of Scientific and Technical Information of China (English)

    侯秋丰; 吕强; 刘雪莱; 史浩峰

    2016-01-01

    The finite element model of Hydraulic release bearing is established to study the influence of the construction of clutch hydraulic release bearing cylinder on the pressing force of sealing ring ,and this model is used for analyzing the process of pressing into the hydraulic release bearing's sealing ring .The characteristic curve of the pressing force of sealing ring and the displacement is obtained .The model is validated by comparing the calculated and experimental result .Then u-sing the established model ,the influence of the bearing cylinder's construction and the sealing ring friction coefficient for the pressing force of seal ring is analyzed .The results show that the pressing force of sealing ring has a big fluctuation when it is just pressed ,then gradually reduces and tends to be stable .If the friction coefficient and the outer diameter of cylinder re-duce or the inner diameter of cylinder increases ,the pressing force of sealing ring would reduce effectively .The developed model and conclusions proposed are instructive for the design and structure optimization of clutch hydraulic release bearing .%为了研究离合器液压分离轴承缸体结构对密封圈压入力的影响,建立了液压分离轴承有限元模型,对液压分离轴承密封圈压入过程进行了分析,得到了密封圈压入力随位移变化的关系曲线,并与相关试验结果进行对比分析,验证了有限元模型的正确性.利用建立的模型,分析了轴承缸体结构参数以及与密封圈摩擦因数对压入力的影响.结果表明,在刚被压入时,密封圈受到的压入力波动较大,随后逐渐减小并趋于稳定.降低摩擦因数,增大缸体的内径和降低缸体外径可以有效地降低密封圈受到的压入力.该建模方法和结论对液压分离轴承的设计和结构优化具有一定的指导意义.

  4. Design and Analysis of Dumbbell-shaped Seal Ring of Hydraulic Oil Pumping System%液压抽油系统哑铃型密封圈设计与分析

    Institute of Scientific and Technical Information of China (English)

    朱拾东; 张建军; 刘猛; 师峻峰; 赵瑞东

    2013-01-01

    In the hydraulic oil pumping system with water as power fluid,the conventional O-ring and other sealing rings cannot meet the sealing requirements of not collusion for high and low pressure fluid. A new type of dumbbell-shaped seal ring was designed and its sealing mechanism was analyzed. The contact deformation and the contact stress distribution on the contact sealing interface under the action of the liquid pressure were analyzed by finite element analysis software. The results show that the designed dumbbell-shaped sealing structure can meet the sealing requirements of 16 MPa differential pressure of the hydraulic oil pumping system.%  在以水作为动力液介质的液压抽油系统中,常规的O型密封圈及其他密封圈都不能满足高、低压流体之间不串通的密封要求。设计了一种新型的哑铃型密封结构,并分析其密封机制;利用有限元软件分析在液体压力作用下密封圈的接触变形、接触密封界面上的接触应力分布。结果表明,设计的哑铃型密封结构可以满足要求液压抽油系统16 MPa压差的密封要求。

  5. Mechanical Deformation of Ship Stern-Shaft Mechanical Face Seals

    Institute of Scientific and Technical Information of China (English)

    朱汉华; 刘正林; 温诗铸; 严新平

    2004-01-01

    In ship propeller shaft systems, the shaft seal is a mechanical face seal, which includes a stationary metal seal ring and a rotating ring.The seal faces are deformed with different loads.The deformation of the seal faces affects the performance of mechanical face seals, which leads to water leakage, so the seal face deformation must be analyzed.A mechanics model with deformation equations was developed to describe ship stern-shaft seals.An example was given to verify the deformation equations.The solution of the deformation equations gives a theoretical basis for the analysis of seal leakage and improvements of seal structures.

  6. Analysis of the Typical Faults of Single-ring Sealed Oil System of 300MW Unit%300MW机组单流环式密封油系统典型故障及分析

    Institute of Scientific and Technical Information of China (English)

    王晓辉

    2013-01-01

    The paper introduced the classification and features of seal oil system of hydrogen cooling generator, and analyzes the typical failure of single ring seal oil system in Matou Power Generation Company.%  介绍了氢冷发电机组密封油系统的分类和特点,并针对马头发电公司单流环密封油系统出现过的几次的典型故障做了详细的分析。

  7. An evaluation of teeth of ringed seals (Phoca hispida) from Greenland as a matrix to monitor spatial and temporal trends of mercury and stable isotopes

    DEFF Research Database (Denmark)

    Aubail, Aurore; Dietz, Rune; Riget, Frank Farsø;

    2010-01-01

    central West Greenland and central East Greenland. These increases were attributed to global changes in environmental Hg levels since no temporal trends in δ15N values were found to support the hypothesis of a diet shift over time. Furthermore, a decreasing temporal trend in δ13C values was observed...... in the teeth of seals from central East Greenland, and explained by a likely change over time towards more pelagic feeding habits; alternatively, the so-known Seuss effect was thought to be responsible for this decrease. Finally, it was concluded that the tooth of ringed seal was a good monitoring tissue...

  8. Seals and sealing handbook

    CERN Document Server

    Flitney, Robert K

    2007-01-01

    Wherever machinery operates there will be seals of some kind ensuring that the machine remains lubricated, the fluid being pumped does not leak, or the gas does not enter the atmosphere. Seals are ubiquitous, in industry, the home, transport and many other places. This 5th edition of a long-established title covers all types of seal by application: static, rotary, reciprocating etc. The book bears little resemblance to its predecessors, and Robert Flitney has re-planned and re-written every aspect of the subject. No engineer, designer or manufacturer of seals can afford to be without this uniq

  9. Status of biodiversity in the Baltic Sea.

    Directory of Open Access Journals (Sweden)

    Henn Ojaveer

    Full Text Available The brackish Baltic Sea hosts species of various origins and environmental tolerances. These immigrated to the sea 10,000 to 15,000 years ago or have been introduced to the area over the relatively recent history of the system. The Baltic Sea has only one known endemic species. While information on some abiotic parameters extends back as long as five centuries and first quantitative snapshot data on biota (on exploited fish populations originate generally from the same time, international coordination of research began in the early twentieth century. Continuous, annual Baltic Sea-wide long-term datasets on several organism groups (plankton, benthos, fish are generally available since the mid-1950s. Based on a variety of available data sources (published papers, reports, grey literature, unpublished data, the Baltic Sea, incl. Kattegat, hosts altogether at least 6,065 species, including at least 1,700 phytoplankton, 442 phytobenthos, at least 1,199 zooplankton, at least 569 meiozoobenthos, 1,476 macrozoobenthos, at least 380 vertebrate parasites, about 200 fish, 3 seal, and 83 bird species. In general, but not in all organism groups, high sub-regional total species richness is associated with elevated salinity. Although in comparison with fully marine areas the Baltic Sea supports fewer species, several facets of the system's diversity remain underexplored to this day, such as micro-organisms, foraminiferans, meiobenthos and parasites. In the future, climate change and its interactions with multiple anthropogenic forcings are likely to have major impacts on the Baltic biodiversity.

  10. Non-contacting fluid ring seal systems for railcar axle bearing systems: Quarterly progress report No. 3, December 16, 1987-March 15, 1988

    Energy Technology Data Exchange (ETDEWEB)

    1988-01-01

    One test rig was completed, and a FR seal prototype test was initiated. No leaks of grease were detected. A used ''D'' sized lip seal was evaluated. New FR seals are being designed. 6 figs. (DLC)

  11. 硅胶圈在立车方滑枕润滑油回收盘中的应用%The Application of Silicone Seal Ring in Vertical Lathe Square Ram's Lube Oil Drain Pan

    Institute of Scientific and Technical Information of China (English)

    周丹; 王冠田

    2014-01-01

    In this paper, to solve the reliability problem of silicone seal ring in vertical lathe Square ram's lube oil drain pan, a kind of silicone ring to seal around the square ram is used to ensure the recycling of oil effectively, test-ed and achieved good results.%针对立车刀架方滑枕润滑油回收盘密封圈可靠性问题,应用硅胶圈实施对方滑枕周边密封,从而保证润滑油得到有效回收,经过试验取得了良好效果。

  12. Mechanical seal with textured sidewall

    Energy Technology Data Exchange (ETDEWEB)

    Khonsari, Michael M.; Xiao, Nian

    2017-02-14

    The present invention discloses a mating ring, a primary ring, and associated mechanical seal having superior heat transfer and wear characteristics. According to an exemplary embodiment of the present invention, one or more dimples are formed onto the cylindrical outer surface of a mating ring sidewall and/or a primary ring sidewall. A stationary mating ring for a mechanical seal assembly is disclosed. Such a mating ring comprises an annular body having a central axis and a sealing face, wherein a plurality of dimples are formed into the outer circumferential surface of the annular body such that the exposed circumferential surface area of the annular body is increased. The texture added to the sidewall of the mating ring yields superior heat transfer and wear characteristics.

  13. Baltic Sea: Radionuclides

    DEFF Research Database (Denmark)

    Nielsen, Sven Poul; Lüning, Maria; Ilus, Erkki;

    2011-01-01

    . Radioactivity inputs into the Baltic Sea from nuclear reprocessing plants in Western Europe have become of minor importance due to significant reduction of discharges in recent years. In terms of input of 137Cs into the Baltic Sea, Chernobyl fallout has contributed about 82% and nuclear weapons test fallout...

  14. (137)Cs, (40)K and (210)Po in marine mammals from the southern Baltic Sea.

    Science.gov (United States)

    Ciesielski, Tomasz; Góral, Marta; Szefer, Piotr; Jenssen, Bjørn Munro; Bojanowski, Ryszard

    2015-12-15

    This study provides information on baseline concentrations of the radionuclides Cesium-137, Potassium-40 and Polonium-210 in sea mammals from the Baltic Sea. The radionuclides were analyzed in the liver, kidney and muscle of harbor porpoises, striped dolphins, and gray and ringed seals from the Polish coast by γ- and α-spectrometry. Median (137)Cs activities were 14.8, 13.2 and 23.2 Bq kg(-1) w.w. in the liver, kidney and muscles, respectively. Activities of (40)K and (210)Po in the respective tissues were found to be 79.1, 79.8 and 111 Bq kg(-1) for (40)K and 58.1, 59.2 and 32.9 Bq kg(-1) for (210)Po. The measured (137)Cs concentrations were extraordinarily high in comparison to those reported in sea mammals from other locations. However, dose assessments did not imply health effects from (137)Cs exposure in Baltic Sea mammals. Correlations between (137)Cs tissue activities and reported sea water concentrations highlight the potential use of marine mammals for biomonitoring purposes.

  15. A morbillivirus causing mass mortality in seals.

    NARCIS (Netherlands)

    A.D.M.E. Osterhaus (Albert)

    1989-01-01

    textabstractDuring an outbreak of a serious apparently infectious disease among harbour seals (Phoca vitulina), which started in the Kattegat area in April 1988 and rapidly spread to the North sea, the Wadden sea and the Baltic sea, greater than 17,000 animals died within a period of eight months. I

  16. Baltic Landscapes : Festival of Images from Baltics

    Index Scriptorium Estoniae

    2000-01-01

    Hanno Soans eesti projektist "Analogue TV" N.E.W.S. (north-east-west-süd) seminaril. Eesti videoprogramm näitusel "Baltic Landscapes" (kunstnikud A. Maimik, K. Kaljo, E-L. Semper, M. Raat, M. Laanemets, K. Sukmit, J. Zoova) Bornholmis

  17. Glass sealing

    Energy Technology Data Exchange (ETDEWEB)

    Brow, R.K.; Kovacic, L.; Chambers, R.S. [Sandia National Labs., Albuquerque, NM (United States)

    1996-04-01

    Hernetic glass sealing technologies developed for weapons component applications can be utilized for the design and manufacture of fuel cells. Design and processing of of a seal are optimized through an integrated approach based on glass composition research, finite element analysis, and sealing process definition. Glass sealing procedures are selected to accommodate the limits imposed by glass composition and predicted calculations.

  18. Status of Understanding for Seal Materials

    Science.gov (United States)

    Brown, P. F.

    1984-01-01

    Material selection for mainshaft face and ring seals, labyrinth seals, accessory gearbox face seals, and lip seals are discussed in light of tribology requirements and a given seal application. Carbon graphite has been found to be one of the best sealing materials and it is widely used in current gas turbine mainshaft and accessory gearbox seals. Its popularity is due to its unique combination of properties which consists of dimensional stability, corrosion resistance, low friction, good self lubricating characteristics, high thermal conductivity and low thermal expansion, the latter two properties combining to provide good thermal shock resistance. A brief description of the seals and the requirements they must meet are discussed to provide insight into the limitations and advantages of the seals in containing the lubricant. A forecast is made of the operational requirements of main shaft and gearbox seals for advanced engines and candidate materials and coatings that may satisfy these advanced engine requirements.

  19. 液压碳石墨密封环激光辅助车削的加工性能研究%Study on machinability for laser-assisted machining of hydraulic carbon-graphite seal rings

    Institute of Scientific and Technical Information of China (English)

    薄纪康; 张海英

    2012-01-01

    为了实现液压碳石墨密封环的高效车削加工,采用激光辅助加工方法,进行了碳石墨密封环材料的激光辅助车削加工研究.考虑到碳石墨密封环材料具有高强度、高硬度等特点,利用激光束对工件进行局部加热,以提高加工效率、减小切削力和刀具磨损.针对碳石墨M104密封环的车削加工过程,进行了常规切削和激光辅助切削的对比实验研究.设计了激光辅助加工的实验流程,并进行了工艺参量的合理选择,得到了较高的切削效率.结果表明,激光辅助切削的主切削力和径向力分别比常规切削下降了23.5%和19.9%;激光辅助切削的切削区温度分布与常规切削相近;刀具磨损和破损的程度较小,能获得较好的表面加工质量.%To perform high efficient turning of hydraulic carbon-graphite seal rings, the laser-assisted machining of the material of carbon-graphite seal ring was conducted using laser pre-heating. The material of carbon-graphite seal rings has the characteristics of high strength and high hardness, and is typical non-metallic difficult-to-machine material. The laser-assisted machining heats the workpiece using laser beam, improving machining efficiency as well as reducing cutting force and tool wear. The turning process of carbon-graphite M104 seal ring was focused on, and the conventional machining was compared with the laser-assisted machining. The experimental process of laser-assisted machining was designed and reasonable process parameters were selected. A high cutting efficiency was obtained. The main cutting force and radial force decreased by 23. 5% and 19. 9% compared with conventional machining. The temperature distribution in the cutting zone of laser-assisted machining is similar to conventional machining. The laser-assisted machining has less tool wear and can get a better surface quality.

  20. Mechanical seals

    CERN Document Server

    Mayer, E

    1977-01-01

    Mechanical Seals, Third Edition is a source of practical information on the design and use of mechanical seals. Topics range from design fundamentals and test rigs to leakage, wear, friction and power, reliability, and special designs. This text is comprised of nine chapters; the first of which gives a general overview of seals, including various types of seals and their applications. Attention then turns to the fundamentals of seal design, with emphasis on six requirements that must be considered: sealing effectiveness, length of life, reliability, power consumption, space requirements, and c

  1. Cyclic volatile methylsiloxanes in fish from the Baltic Sea.

    Science.gov (United States)

    Kierkegaard, Amelie; Bignert, Anders; McLachlan, Michael S

    2013-10-01

    Laboratory studies suggest that the cyclic volatile methylsiloxanes (cVMS) octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) and dodecamethylcyclohexasiloxane (D6) will persist in the aquatic environment and bioaccumulate in fish. Here these cVMS were measured in herring collected in the Swedish waters of the Baltic Sea and the North Sea and in grey seals from the Baltic Proper. D4, D5, and D6 were present in herring muscle at concentrations around 10, 200, and 40ngg(-1) lipid weight, respectively. The ratio of these concentrations was similar to the relative magnitude of estimated emissions to water, suggesting that the efficiency of overall transfer through the environment and food web was similar (within a factor 2-3) for the three chemicals. The concentrations of D5 and D6 were similar in herring caught in the highly populated Baltic Proper and in the less populated Bothnian Sea and Bothnian Bay. The D4 concentrations were lower at the most remote northern station, suggesting that D4 is less persistent than D5 and D6. Herring from the North Sea had lower levels of all three chemicals. The concentrations of D4, D5 and D6 in grey seal blubber were lower than the lipid normalized concentrations in herring, indicating that they do not biomagnify in grey seals.

  2. Baltic Exchange toodi Tallinna

    Index Scriptorium Estoniae

    2007-01-01

    Viimane osa merekonteineritesse kokkupakitud Londoni laevandus- ja merebörsi Baltic Exchange'i endise peakorteri detailidest jõudis 2007. a. juunis Tallinna. Hoone detailid ostnud ärimehed Heiti Hääl ja Eerik-Niiles Kross plaanivad leida hoonele koha Tallinna kesklinnas. E.-N. Krossi kommentaar

  3. South Baltic Wind Atlas

    DEFF Research Database (Denmark)

    Pena Diaz, Alfredo; Hahmann, Andrea N.; Hasager, Charlotte Bay

    A first version of a wind atlas for the South Baltic Sea has been developed using the WRF mesoscale model and verified by data from tall Danish and German masts. Six different boundary-layer parametrization schemes were evaluated by comparing the WRF results to the observed wind profiles at the m...

  4. Baltic financial markets attractive

    Index Scriptorium Estoniae

    2004-01-01

    Tallinnas toimunud konverentsil East Baltic Summit tõdesid eksperdid, et Balti riikidel on välisinvestorite silmis positiivne maine. Esinejate hulgas olid Rootsi endine peaminister Carl Bildt, Baltimaade juhtivaid eksperte Bengt Dennis, investeerimispankur Rain Lõhmus, East Capitali president Peter Elam Hakansson

  5. Baltic Sea: Radionuclides

    DEFF Research Database (Denmark)

    Nielsen, Sven Poul; Lüning, Maria; Ilus, Erkki

    2010-01-01

    The most significant source of anthropogenic radioactivity in the Baltic Sea is fallout from the accident at the Chernobyl nuclear power plant in 1986. The second most important source is global fallout from atmospheric nuclear weapons tests carried out during the late 1950s and early 1960s. Radi...

  6. Baltic Earth - Earth System Science for the Baltic Sea Region

    Science.gov (United States)

    Meier, Markus; Rutgersson, Anna; Lehmann, Andreas; Reckermann, Marcus

    2014-05-01

    The Baltic Sea region, defined as its river catchment basin, spans different climate and population zones, from a temperate, highly populated, industrialized south with intensive agriculture to a boreal, rural north. It encompasses most of the Scandinavian Peninsula in the west; most of Finland and parts of Russia, Belarus, and the Baltic states in the east; and Poland and small parts of Germany and Denmark in the south. The region represents an old cultural landscape, and the Baltic Sea itself is among the most studied sea areas of the world. Baltic Earth is the new Earth system research network for the Baltic Sea region. It is the successor to BALTEX, which was terminated in June 2013 after 20 years and two successful phases. Baltic Earth stands for the vision to achieve an improved Earth system understanding of the Baltic Sea region. This means that the research disciplines of BALTEX continue to be relevant, i.e. atmospheric and climate sciences, hydrology, oceanography and biogeochemistry, but a more holistic view of the Earth system encompassing processes in the atmosphere, on land and in the sea as well as in the anthroposphere shall gain in importance in Baltic Earth. Specific grand research challenges have been formulated, representing interdisciplinary research questions to be tackled in the coming years. A major means will be scientific assessments of particular research topics by expert groups, similar to the BACC approach, which shall help to identify knowledge gaps and develop research strategies. Preliminary grand challenges and topics for which Working Groups have been installed include: • Salinity dynamics in the Baltic Sea • Land-Sea biogeochemical feedbacks in the Baltic Sea region • Natural hazards and extreme events in the Baltic Sea region • Understanding sea level dynamics in the Baltic Sea • Understanding regional variability of water and energy exchange • Utility of Regional Climate Models • Assessment of Scenario Simulations

  7. Analysis of Deformation in the Manufacturing Process of Seal Ring with Wavy Face Using the Pre-deformation Plane Lapping Method%周向波度密封环预变形平面研磨加工中的变形分析

    Institute of Scientific and Technical Information of China (English)

    周平; 戴恒震; 金洙吉; 王宇; 康仁科; 郭东明

    2015-01-01

    端面周向波度密封是一种非接触机械密封,它具有泄漏低、刚度大和寿命长等优点,在核主泵和透平机械等旋转机械密封中有很好的应用前景.周向波度密封环端面面形非常复杂,加工极为困难.提出一种周向波度密封环的预变形平面研磨加工方法,并对其中最为关键的预变形过程进行了分析.通过对预变形过程中密封环变形特性的有限元分析,揭示了预紧力和密封环端面变形的关系,通过周期性反向扭矩的作用获得了满足要求的表面预变形.通过预变形夹具的研制和平面研磨工艺研究,完成了周向波度密封环的加工,证明了预变形平面研磨加工方法加工周向波度密封环的可行性.%Sealing ring with wavy face is a kind of non-contact mechanical seal, which has advantages in low leakage, high stiffness and long life. It has a good application prospect in mechanical seal structure of nuclear reactor coolant pump and turbo machine. However, the manufacture of sealing ring with wavy face is a very challenging job due to the complex curve face. A pre-deformation plane lapping method of sealing ring with wavy face is proposed here, and the pre-deformation, which is the most critical process, is analyzed. The relationship between the pre-deformation force and the end face deformation of sealing ring is revealed through finite element analysis. It is found that the required surface deformation can be obtained by applying periodic reverse torque. Through the development of pre-deformation fixture and the research of lapping technology of ring surface, sealing ring with wavy face is successfully manufactured. The possibility of the manufacturing of sealing ring with wavy face using the pre-deformation plane lapping method is verified theoretically and experimentally.

  8. Think - Baltic Extension / Kalle Kask

    Index Scriptorium Estoniae

    Kask, Kalle

    2002-01-01

    Tallinna TÜ Rehabilitatsiooni tehnoloogia keskus korraldas pressikonverentsi, kus tutvustati osalemist EL V raamprogrammis Think - Baltic Extension, mis on suunatud puuetega inimeste tööhõive tagamisele

  9. Mass mortality in seals caused by a newly discovered morbillivirus.

    NARCIS (Netherlands)

    A.D.M.E. Osterhaus (Albert); J. Groen (Jan); H.E.M. Spijkers (Ine); H.W.J. Broeders; F.G.C.M. Uytdehaag (Fons); P. de Vries (Petra); J.S. Teppema; I.K.G. Visser (Ilona); M.W.G. van de Bildt (Marco); E.J. Vedder (Lies)

    1990-01-01

    textabstractDuring a recent disease outbreak among harbour seals (Phoca vitulina) in the North and Baltic seas, more than 17,000 animals have died. The clinical symptoms and pathological findings were similar to those of distemper in dogs. Based on a seroepizootiological study, using a canine distem

  10. Global population structure and demographic history of the grey seal

    DEFF Research Database (Denmark)

    Klimova, A.; Phillips, C. D.; Fietz, Katharina;

    2014-01-01

    a little over 10 000 years ago, consistent with the last proposed isolation of the Baltic Sea. Approximate Bayesian computation also identified genetic signals consistent with postglacial population expansion across much of the species range, suggesting that grey seals are highly responsive to changes...

  11. 高压大型天然气快开盲板用C形橡胶圈密封性能分析%Sealing Performance Analysis of Rubber C-ring for High-pressure Natural Gas Quick-opening Closure

    Institute of Scientific and Technical Information of China (English)

    石莹; 陈平; 周淑敏

    2015-01-01

    The finite element model of rubber C⁃ring used in the quick⁃opening blind plate of domestic high⁃pressure natural gas filter was established.The influences of the seal groove width,internal pressure,initial seal clearance,hardness of materials,notch radius,rim diameter of steel⁃ring on the sealing performance of rubber C⁃ring were analyzed by using ABAQUS software,and the reasonable range of these parameters were suggested.The results show that the hardness of mate⁃rials has little effect on seal performance,while the seal groove width has a certain impact on the sealing reliability,with the sealing groove width increasing,the maximum contact pressure is decreased and the sealing reliability is also decreased. With the increase of internal pressure,the difference between the maximum contact pressure and internal pressure is in⁃creased,the sealing reliability is increased.With the increase of initial gap seal,the stress is increased and the sealing reli⁃ability is decreased.The sealing notch chamfer radius has large influence on the shear failure of sealing ring,the increasing of chamfer radius will result in large possibility of shear failure.Steel⁃ring diameter has large effect on the strain and stress of C⁃shaped rubber ring,and he increasing of steel⁃ring diameter will result in the decrease of shear stress.%针对国内高压大型天然气过滤器快开盲板用C形橡胶密封圈,利用ABAQUS建立其有限元模型,分析密封槽宽度、内压、初始密封间隙、材料硬度、槽口倒角半径、钢圈直径对其性能的影响,得到这些参数的合理取值范围。结果表明:材料硬度对密封圈密封性能的影响较小,密封槽宽度对密封可靠度有一定影响,随密封槽宽度增加,最大接触压力呈下降趋势,密封可靠度有所降低;随着内压的增加,最大接触压力与内压的差值呈增大趋势,密封可靠性增加;随初始密封间隙增加,应力增加

  12. Ceramic Seal.

    Energy Technology Data Exchange (ETDEWEB)

    Smartt, Heidi A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Romero, Juan A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Custer, Joyce Olsen [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hymel, Ross W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Krementz, Dan [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Gobin, Derek [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Harpring, Larry [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Martinez-Rodriguez, Michael [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Varble, Don [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); DiMaio, Jeff [Tetramer Technologies, Pendleton, SC (United States); Hudson, Stephen [Tetramer Technologies, Pendleton, SC (United States)

    2016-11-01

    Containment/Surveillance (C/S) measures are critical to any verification regime in order to maintain Continuity of Knowledge (CoK). The Ceramic Seal project is research into the next generation technologies to advance C/S, in particular improving security and efficiency. The Ceramic Seal is a small form factor loop seal with improved tamper-indication including a frangible seal body, tamper planes, external coatings, and electronic monitoring of the seal body integrity. It improves efficiency through a self-securing wire and in-situ verification with a handheld reader. Sandia National Laboratories (SNL) and Savannah River National Laboratory (SRNL), under sponsorship from the U.S. National Nuclear Security Administration (NNSA) Office of Defense Nuclear Nonproliferation Research and Development (DNN R&D), have previously designed and have now fabricated and tested Ceramic Seals. Tests have occurred at both SNL and SRNL, with different types of tests occurring at each facility. This interim report will describe the Ceramic Seal prototype, the design and development of a handheld standalone reader and an interface to a data acquisition system, fabrication of the seals, and results of initial testing.

  13. Ferrules seals

    Science.gov (United States)

    Smith, J.L.

    1984-07-10

    A device is provided for sealing an inner tube and an outer tube without excessively deforming the tubes. The device includes two ferrules which cooperate to form a vacuum-tight seal between the inner tube and outer tube and having mating surfaces such that overtightening is not possible. 3 figs.

  14. Stabilizing geometry for hydrodynamic rotary seals

    Science.gov (United States)

    Dietle, Lannie L.; Schroeder, John E.

    2010-08-10

    A hydrodynamic sealing assembly including a first component having first and second walls and a peripheral wall defining a seal groove, a second component having a rotatable surface relative to said first component, and a hydrodynamic seal comprising a seal body of generally ring-shaped configuration having a circumference. The seal body includes hydrodynamic and static sealing lips each having a cross-sectional area that substantially vary in time with each other about the circumference. In an uninstalled condition, the seal body has a length defined between first and second seal body ends which varies in time with the hydrodynamic sealing lip cross-sectional area. The first and second ends generally face the first and second walls, respectively. In the uninstalled condition, the first end is angulated relative to the first wall and the second end is angulated relative to the second wall. The seal body has a twist-limiting surface adjacent the static sealing lip. In the uninstalled condition, the twist-limiting surface is angulated relative to the peripheral wall and varies along the circumference. A seal body discontinuity and a first component discontinuity mate to prevent rotation of the seal body relative to the first component.

  15. Advanced helium purge seals for Liquid Oxygen (LOX) turbopumps

    Science.gov (United States)

    Shapiro, Wilbur; Lee, Chester C.

    1989-01-01

    Program objectives were to determine three advanced configurations of helium buffer seals capable of providing improved performance in a space shuttle main engine (SSME), high-pressure liquid oxygen (LOX) turbopump environment, and to provide NASA with the analytical tools to determine performance of a variety of seal configurations. The three seal designs included solid-ring fluid-film seals often referred to as floating ring seals, back-to-back fluid-film face seals, and a circumferential sectored seal that incorporated inherent clearance adjustment capabilities. Of the three seals designed, the sectored seal is favored because the self-adjusting clearance features accommodate the variations in clearance that will occur because of thermal and centrifugal distortions without compromising performance. Moreover, leakage can be contained well below the maximum target values; minimizing leakage is important on the SSME since helium is provided by an external tank. A reduction in tank size translates to an increase in payload that can be carried on board the shuttle. The computer codes supplied under this program included a code for analyzing a variety of gas-lubricated, floating ring, and sector seals; a code for analyzing gas-lubricated face seals; a code for optimizing and analyzing gas-lubricated spiral-groove face seals; and a code for determining fluid-film face seal response to runner excitations in as many as five degrees of freedom. These codes proved invaluable for optimizing designs and estimating final performance of the seals described.

  16. Seal Counts

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Database of seal counts from aerial photography. Counts by image, site, species, and date are stored in the database along with information on entanglements and...

  17. Baltic nuclear projects

    Energy Technology Data Exchange (ETDEWEB)

    Adlys, Gediminas; Adliene, Diana [Kaunas Univ. of Technology (Lithuania)

    2009-07-01

    The Authors discuss the Baltic energy policy with respect to new nuclear power plants for Lithuania, Belarus and the Kaliningrad region. The construction of a new nuclear power plant in Lithuania would threaten Russian interests in the region. Therefore Lithuania is looking to Russian plans to build a new nuclear power plant in the Kaliningrad region as an attempt to subvert Lithuania's foreign partners and potential investors from participating in the Visaginas NPP project. However, the authors conclude, that the Visaginas NPP project is and must be the preferential project for the EU and NATO member states.

  18. Organising Baltic Jazz festival

    OpenAIRE

    Väärä, Emmi

    2016-01-01

    The purpose of this paper was to clarify how Baltic Jazz festival is organised in a matter of project based thesis, where the main product was the festival held in 2016. The festival is located on Kemiönsaari in Turku Archipelago and it has been up and running for 30 years next year. The paper includes seven key concepts that are important for understanding the field of event management as well as the main operations according to the literature found about special events and festivals. ...

  19. 77 FR 76706 - Endangered and Threatened Species; Threatened Status for the Arctic, Okhotsk, and Baltic...

    Science.gov (United States)

    2012-12-28

    ..., primarily due to concerns about threats to their habitat from climate warming and loss of sea ice. The... review by five scientists with expertise in ringed seal biology, Arctic sea ice, climate change, and... projections and analysis of future sea ice, and in particular snow cover, for Arctic ringed seals (76 FR...

  20. STUDY ON MECHANICAL DEFORMATIONS OF THE PRIMARY FRONTAL SEALING

    Directory of Open Access Journals (Sweden)

    Monica BÂLDEA

    2015-05-01

    Full Text Available In many applications one of the primary sealing rings is mounted pressed into another ring, tightening materials to be made makes the required stretched tension in the outer ring and compression in the inner ring.It will be considered as the basis for calculating ultimate elongation for tenacious materials and breaking limit for brittle materials.

  1. Electric energy cooperation in the Baltic Sea region and the role of Russia in it

    Directory of Open Access Journals (Sweden)

    Zverev Yuri

    2013-06-01

    Full Text Available This article examines cooperation in the electric energy sector in the Baltic region. The author explores the existing undersea HVDC power exchange projects. It is emphasised that cooperation in the electric energy sector is concentrated largely in the EU member states despite earlier plans to establish the Baltic energy ring, which would also include Russia and Belarus. The author stresses that one of the most acute problems for the EU today is overcoming isolation of the energy systems of the Baltic States (Lithuania, Latvia, and Estonia from that of the major part of the EU. This task has become especially relevant after the closing of the Ignalina NPP (Lithuania, which used to be the primary energy source for the three Baltic States. The article examines key projects of the construction of new international power transmission lines in the framework of the Baltic Energy Market Interconnection Plan (BEMIP and the prospects of the Visaginas NPP (Lithuania in solving energy problems of the Baltic States. The author analyses Russia’s role in the electric energy market and focuses on a possible increase of the country’s energy market share following the construction of the Baltic NPP and the export of generated electric energy to Poland, Lithuania, Germany, and Sweden. The author concludes that the prospects of Russia’s energy export to the Baltic Sea region will be determined not only by technological, economic and market factors, but rather by the general state of relations between Russia and the EU. Moreover, a lot depends on Lithuania’s decision on the construction of the Visaginas NPP, as well as the way the EU and the Baltic States solve the problem of energy supply in case the NPP project is terminated.

  2. Metal Sealing Performance of Subsea X-tree Wellhead Connector Sealer

    Institute of Scientific and Technical Information of China (English)

    ZHAO Honglin; CHEN Rui; LUO Xiaolan; DUAN Menglan; LU Yinghui; FU Guowei; TIAN Hongping; YE Daohui

    2015-01-01

    The metal sealing performance of subsea X-tree wellhead connectors is crucial for the safety and reliability of subsea X-trees. In order to establish the theoretical relation between metal sealing ring’s contact stress and its structural parameters and working pressure, a mechanical analysis method for double-cone sealing of high pressure vessels is applied in analyzing the metal sealing ring under the condition of preload and operation. As a result, the formula of the unit sealing load for the metal sealing ring under operation with residual preload is shown in this paper, which ensures that the metal sealing ring has an excellent sealing effect and can prevent the metal sealing ring from yielding. Besides, while analyzing the sealing process of the metal sealing ring, the change rule of contact stress and working pressure is concluded here, putting forward that the structural parameters of the metal sealing ring are the major factors affecting the change rule. Finally, the analytical solution through theoretical analysis is compared with the simulation result through finite element analysis in a force feedback experiment, and both are consistent with each other, which fully verifies for the design and calculation theory on metal sealing ring’s contact stress and its structural parameters and working pressure deduced in this paper. The proposed research will be treated as an applicable theory guiding the design of metal seal for subsea X-tree wellhead connectors.

  3. Collar nut and thrust ring

    Science.gov (United States)

    Lowery, Guy B.

    1991-01-01

    A collar nut comprises a hollow cylinder having fine interior threads at one end for threadably engaging a pump mechanical seal assembly and an inwardly depending flange at the other end. The flange has an enlarged portion with a groove for receiving an O-ring for sealing against the intrusion of pumpage from the exterior. The enlarged portion engages a thrust ring about the pump shaft for crushing a hard O-ring, such as a graphite O-ring. The hard O-ring seals the interior of the mechanical seal assembly and pump housing against the loss of lubricants or leakage of pumpage. The fine threads of the hollow cylinder provide the mechanical advantage for crushing the hard O-ring evenly and easily with a hand tool from the side of the collar nut rather than by tightening a plurality of bolts from the end and streamlines the exterior surface of the mechanical seal. The collar nut avoids the spatial requirements of bolt heads at the end of a seal and associated bolt head turbulence.

  4. Study on a new type of sealing - regeneration-labyrinth sealing for displacer in cryocoolers: Part I - Theoretical study

    Science.gov (United States)

    Liu, L. Q.; Zhang, L.

    2000-02-01

    A new concept of sealing structure - regeneration-labyrinth sealing has been put forward to substitute for sealing rings that influence seriously the performance of cryocoolers. A program, which can simulate the thermophysical process occurring in the sealing structure, is developed consequently. Using numerical simulation, the reasonable structure of the regeneration-labyrinth sealing has been determined. The influences of some parameters, such as the heat transfer coefficient of forced convection, the cylinder-displacer gap, the diameter and length of cylinder on the losses of cooling capacity have been studied numerically. As a result, the designing principle of the new type of sealing is obtained.

  5. Python fiber optic seal

    Energy Technology Data Exchange (ETDEWEB)

    Ystesund, K.; Bartberger, J.; Brusseau, C.; Fleming, P.; Insch, K.; Tolk, K.

    1993-08-01

    Sandia National Laboratories has developed a high security fiber optic seal that incorporates tamper resistance features that are not available in commercial fiber optic seals. The Python Seal is a passive fiber optic loop seal designed to give indication of unauthorized entry. The seal includes a fingerprint feature that provides seal identity information in addition to the unique fiber optic pattern created when the seal is installed. The fiber optic cable used for the seal loop is produced with tamper resistant features that increase the difficulty of attacking that component of a seal. A Seal Reader has been developed that will record the seal signature and the fingerprint feature of the seal. A Correlator software program then compares seal images to establish a match or mismatch. SNL is also developing a Polaroid reader to permit hard copies of the seal patterns to be obtained directly from the seal.

  6. Strengthening Nordic-Baltic Defense Capabilities

    DEFF Research Database (Denmark)

    Breitenbauch, Henrik Ø.

    2014-01-01

    , there is no reason why this framework could not be extended to the Baltic states.36 A NORBALDEFCO would not only cement the prominent role of Sweden and Finland within NATO as premier partners, it would also formally continue the work begun with Baltic independ- ence after the Cold War, and furthermore strengthen...... the NATO aspect of Nordic-Baltic security....

  7. Method of forming shrink-fit compression seal

    Science.gov (United States)

    Podgorski, T. J. (Inventor)

    1977-01-01

    A method for making a glass-to-metal seal is described. A domed metal enclosure having a machined seal ring is fitted to a glass post machined to a slight taper and to a desired surface finish. The metal part is then heated by induction in a vacuum. As the metal part heats and expands relative to the glass post, the metal seal ring, possessing a higher coefficient of expansion than the glass post, slides down the tapered post. Upon cooling, the seal ring crushes against the glass post forming the seal. The method results in a glass-to-metal seal possessing extremely good leak resistance, while the parts are kept clean and free of the contaminants.

  8. Soft Wire Seals For High Temperatures And Pressures

    Science.gov (United States)

    Tsou, Peter

    1996-01-01

    Soft metal wires used to make O-ring and similar seals for vessels, flanges, and fittings subject to pressures equal to or greater than 1,000 psi and temperatures equal to or greater than 100 degrees C. Seals containing soft metal wires made inexpensively because fabricated to looser tolerances like those of lower-temperature, lower-pressure elastomeric-O-ring seals, which they resemble. Seals also made with noncircular grooves and with soft metals other than aluminum. For example, gold performs well, though expensive. For other applications, silver good choice.

  9. 有风时大型油罐密封圈火灾下油罐间的安全距离%Safe Distance of Large Storage Tank’s Seal Ring Fire Under Wind Condition

    Institute of Scientific and Technical Information of China (English)

    关新凤; 刘德俊; 魏亚峰; 祝贺; 葛岚; 杨萍

    2015-01-01

    针对有风时大型原油储罐火灾安全问题,以密封圈火灾着火油罐作为研究对象,采用编程软件对着火油罐的辐射区域进行模拟计算,进而确定储罐间的安全距离。研究结果表明,风速一定时,辐射热量随着距火焰的距离增加而降低;同一着火油罐,热辐射情况随着风速的加大而加剧;风速为4 m/s 时,相邻油罐间的安全距离为31.2 m。%With respect to the security issue of large storage tanks’ fire, taking crude oil tank’s seal ring fire as the research object, programming software was used to simulate and calculate the thermal radiation of burning storage tank, which can get the safe distance between the tanks. The study results show that, under the condition of certain weed speed, the thermal radiation decreases with increasing of the distance reaching the burning storage tank. For the same burning tank, with increasing of the wind speed, the thermal radiation increases. When the wind speed is 4 m/s, the safe distance between the tanks is 31.2 m.

  10. Turbine with radial acting seal

    Energy Technology Data Exchange (ETDEWEB)

    Eng, Darryl S; Ebert, Todd A

    2016-11-22

    A floating brush seal in a rim cavity of a turbine in a gas turbine engine, where the floating brush seal includes a seal holder in which the floating brush seal floats, and a expandable seal that fits within two radial extending seal slots that maintains a seal with radial displacement of the floating brush seal and the seal holder.

  11. Reactor coolant pump shaft seal behavior during station blackout

    Energy Technology Data Exchange (ETDEWEB)

    Kittmer, C.A.; Wensel, R.G.; Rhodes, D.B.; Metcalfe, R.; Cotnam, B.M.; Gentili, H.; Mings, W.J.

    1985-04-01

    A testing program designed to provide fundamental information pertaining to the behavior of reactor coolant pump (RCP) shaft seals during a postulated nuclear power plant station blackout has been completed. One seal assembly, utilizing both hydrodynamic and hydrostatic types of seals, was modeled and tested. Extrusion tests were conducted to determine if seal materials could withstand predicted temperatures and pressures. A taper-face seal model was tested for seal stability under conditions when leaking water flashes to steam across the seal face. Test information was then used as the basis for a station blackout analysis. Test results indicate a potential problem with an elastomer material used for O-rings by a pump vendor; that vendor is considering a change in material specification. Test results also indicate a need for further research on the generic issue of RCP seal integrity and its possible consideration for designation as an unresolved safety issue.

  12. Impaired cellular immune response in harbour seals (Phoca vitulina) feeding on environmentally contaminated herring.

    NARCIS (Netherlands)

    R.L. de Swart (Rik); P.S. Ross (Peter); H.H. Timmerman (Helga); H.W. Vos (Helma); P.J.H. Reijnders; J.G. Vos (Joseph); A.D.M.E. Osterhaus (Albert)

    1995-01-01

    textabstractIn a 2.5-year immunotoxicological study, two groups of captive harbour seals (Phoca vitulina) were fed herring from the heavily polluted Baltic Sea or from the relatively uncontaminated Atlantic Ocean. Blood samples were collected at regular intervals, and functional immunological parame

  13. Regenerator seal

    Science.gov (United States)

    Davis, Leonard C.; Pacala, Theodore; Sippel, George R.

    1981-01-01

    A method for manufacturing a hot side regenerator cross arm seal assembly having a thermally stablilized wear coating with a substantially flat wear surface thereon to seal between low pressure and high pressure passages to and from the hot inboard side of a rotary regenerator matrix includes the steps of forming a flat cross arm substrate member of high nickel alloy steel; fixedly securing the side edges of the substrate member to a holding fixture with a concave surface thereacross to maintain the substrate member to a slightly bent configuration on the fixture surface between the opposite ends of the substrate member to produce prestress therein; applying coating layers on the substrate member including a wear coating of plasma sprayed nickel oxide/calcium flouride material to define a wear surface of slightly concave form across the restrained substrate member between the free ends thereon; and thereafter subjecting the substrate member and the coating thereon to a heat treatment of 1600.degree. F. for sixteen hours to produce heat stabilizing growth in the coating layers on the substrate member and to produce a thermally induced growth stress in the wear surface that substantially equalizes the prestress in the substrate whereby when the cross arm is removed from the fixture surface following the heat treatment step a wear face is formed on the cross arm assembly that will be substantially flat between the ends.

  14. Baltic Exchange teper v Tallinne

    Index Scriptorium Estoniae

    2007-01-01

    Viimane osa merekonteineritesse kokkupakitud Londoni laevandus- ja merebörsi Baltic Exchange'i endise peakorteri detailidest jõudis 2007. a. juunis Tallinna. Hoone detailid ostnud ärimehed Heiti Hääl ja Eerik-Niiles Kross plaanivad leida hoonele koha Tallinna kesklinnas. E.-N. Krossi kommentaar

  15. [Pietro U. Dini. Prelude to Baltic linguistics : earliest theories about Baltic languages (16th century)] / Stefan Donecker

    Index Scriptorium Estoniae

    Donecker, Stefan, 1977-

    2015-01-01

    Arvustus: Dini, Pietro U. Prelude to Baltic linguistics : earliest theories about Baltic languages (16th century). (On the boundary of two worlds : identity, freedom, and moral imagination in the Baltics, 36). Verlag Rodopi, Amsterdam und New York 2014

  16. Simulation Analysis of Spherical Mechanical Seal Property of Marine Stern Shaft

    Directory of Open Access Journals (Sweden)

    Zhou Xu Hui

    2016-01-01

    Full Text Available The finite element model of spherical mechanical seal wasestablished with ANSYS, and the influence of seawater pressure, shaft speed and other factors on the sealing performance was discussed. The study results show that local contact situation of the spherical mechanical seal is in the outside of the seal rings, and both maximum contact pressure and temperature appearat the same position. As sea water pressure and stern shaft rotary speed are increased, the contact pressure and temperature of the spherical seal surface are raised, and when the contact pressure of seal surface is 0, the spherical seal surface forms two zones including contact one and clearance zone. The former is near the outside of the seal ring, the lateris close to the inside of one. These research results are of important theoretical significance and engineering application value for the development of new kinds of mechanical seals, and improvement of both safety and survivability of underwater vehicles.

  17. Parimad suhtekorraldusteod konkursil Baltic PR Awards

    Index Scriptorium Estoniae

    2012-01-01

    Balti riikide suhtekorraldusliidud koostöös Rahvusvahelise Avalike Suhete Assotsiatsiooniga (IPRA) korraldavad 2001. aastast iga aasta kommunikatsioonijuhtimisalast auhinnakonkurssi Baltic PR Awards

  18. Seal design alternatives study

    Energy Technology Data Exchange (ETDEWEB)

    Van Sambeek, L.L. [RE/SPEC Inc., Rapid City, SD (US); Luo, D.D.; Lin, M.S.; Ostrowski, W.; Oyenuga, D. [Parsons Brinckerhoff Quade & Douglas, Inc., San Francisco, CA (US)

    1993-06-01

    This report presents the results from a study of various sealing alternatives for the WIPP sealing system. Overall, the sealing system has the purpose of reducing to the extent possible the potential for fluids (either gas or liquid) from entering or leaving the repository. The sealing system is divided into three subsystems: drift and panel seals within the repository horizon, shaft seals in each of the four shafts, and borehole seals. Alternatives to the baseline configuration for the WIPP seal system design included evaluating different geometries and schedules for seal component installations and the use of different materials for seal components. Order-of-magnitude costs for the various alternatives were prepared as part of the study. Firm recommendations are not presented, but the advantages and disadvantages of the alternatives are discussed. Technical information deficiencies are identified and studies are outlined which can provide required information.

  19. Physical oceanography of the Baltic Sea

    Energy Technology Data Exchange (ETDEWEB)

    Leppaeranta, Matti [Helsinki Univ. (Finland). Dept. of Physics; Myrberg, Kai [Finnish Institute of Marine Research, Helsinki (Finland)

    2009-07-01

    The Baltic Sea oceanographic research community is wide and the research history is over 100 years old. Nevertheless, there is still no single, coherent book on the physical oceanography of the Baltic Sea as a whole. There is a strong need for such a book, coming from working oceanographers as well as the university teaching programmes in advanced undergraduate to graduate levels. In the regional conference series in physical oceanography (Baltic Sea Science Conference, Baltic Sea Oceanographers' conference, Baltex-conferences) about 500 scientists take part regularly. Even more scientists work in the fields of marine biology, chemistry and the environment, and they need information on the physics of the Baltic Sea as well. There are nine countries bordering on the Baltic Sea and five more in the runoff area. The Baltic Sea as a source of fish, means of transportation and leisure activities is highly important to the regional society. In the runoff area there are a total of 85 million people. Research and protection strategies need to be developed, as the Baltic Sea is probably the most polluted sea in the world. Since the Baltic Sea has become an inner sea of the EU (apart from small shore parts of Russia in Petersburg and Kaliningrad), it is anticipated that the importance of the region will consequently rise. The book will arouse interest among students, scientists and decision makers involved with the Baltic problems. It will also give important background information for those working with biogeochemical processes in the Baltic Sea, because the physical forcing for those processes is of vital importance. (orig.)

  20. Thermo-Mechanical Test of Seal System in Flexible Pipe End Fittings

    DEFF Research Database (Denmark)

    Banke, Lars

    1999-01-01

    The purpose of the end fitting seal system is to provide a leak tight termination in a flexible pipe. The seal system in a NKT flexible pipe end fitting consists of a number of ring gaskets mounted on the polymeric internal pressure sheath of the pipe. When the seal is energised the gaskets are d...

  1. Verbal Aspects in Germanic, Slavic, and Baltic.

    Science.gov (United States)

    Senn, Alfred

    1949-01-01

    This study examines the theory of Prokosch concerning the Germanic-Slavic-Baltic tense and aspect systems. The interrelatedness and influence of languages and dialects in Slavic (Russian and Old Church Slavic), Baltic (Lithuanian), and Germanic (Old High German and Gothic) are demonstrated. Examples illustrating the use of the perfective present…

  2. AirBaltic says RIX favors Ryanair

    Index Scriptorium Estoniae

    2011-01-01

    Riia lennujaama juht märkis 10. märtsi telesaates, et airBaltic ei saa oma arveid õigeks ajaks makstud. AirBaltic süüditab lennujaama Ryanairi soosimises. Valitsus kaalub airBalticule investorite otsimist

  3. BALTIC NATIONAL TRANSMISSION NETWORK DEVELOPMENT TENDENCY

    Directory of Open Access Journals (Sweden)

    I. N. Olejnikova

    2010-06-01

    Full Text Available The article discusses the development of Baltic transmission networks, related to the program of the European Union (EU to improve the security of energy supply, competitiveness and improve the development. Infrastructure projects to meet the needs of electricity in the EU are considered. The highlight issues are plan of Baltic energy markets merging and Latvian energy market development tendency

  4. Behavior of primary coolant pump shaft seals during station blackout conditions

    Energy Technology Data Exchange (ETDEWEB)

    Hill, R.C.; Rhodes, D.B.

    1986-09-12

    An assessment is made of the ability of typical Reactor Coolant Pump (RCP) Shaft Seals to withstand the conditions predicted for a station blackout (loss of all alternating current power) at a nuclear power station. Several factors are identified that are key to seal stability including inlet fluid conditions, pressure downstream of the seal, and geometrical details of the seal rings. Limits for stable seal operation are determined for various combinations of these factors, and the conclusion is drawn that some RPC seals would be near the threshold of instability during a station blackout. If the threshold were exceeded, significant leakage of coolant from the primary coolant system could be expected.

  5. Parameters important to reactor coolant pump seal stability during station blackout

    Energy Technology Data Exchange (ETDEWEB)

    Hill, R.C.; Rhodes, D.B.

    1986-10-24

    An assessment is made of the ability of typical Reactor Coolant Pump (RCP) Shaft Seals to withstand the conditions predicted for a station blackout (loss of all alternating current power) at a nuclear power station. Several factors are identified that are key to seal stability including inlet fluid conditions, pressure downstream of the seal, and geometrical details of the seal rings. Limits for stable seal operation are determined for various combinations of these factors, and the conclusion is drawn that some RPC seals would be near or over the threshold of instability during a station blackout. If the threshold were exceeded, significant leakage of coolant from the primary coolant system could be expected.

  6. Timing of the Baltic Ice Lake in the eastern Baltic

    Directory of Open Access Journals (Sweden)

    Jüri Vassiljev

    2013-07-01

    Full Text Available A shoreline database for the Baltic, covering the Late Weichselian and Holocene, was compiled. The database includes about 1600 sites from Estonia, Latvia, Lithuania, Finland, NW Russia, Poland, Sweden and was used to create a GIS-based palaeogeographical reconstructions on the development of the Baltic Ice Lake (BIL. The formation of thehighest shoreline of the BIL in Estonia was connected with the development of the Pandivere ice marginal zone (Estonia and the lowest with the Salpausselkä ice-marginal formations (Finland. There was a well-accepted knowledge that the Pandivere ice marginal zone correlates with the Neva ice marginal zone in NW Russia dated to 13 300 cal yr BP. Recent studies of the late glacial sites in northern Estonia indicate that the age of the Pandivere ice marginal zone and hence the highest shoreline of the BIL A1 is about 13 800–14 000 cal yr BP. It was followed by the BIL stage A2, which formed in front ofthe Palivere ice marginal belt about 13 200–13 500 cal yr BP. The final drainage of the BIL took place about 11 650 cal yr BP. The timing of the BIL stages was derived from AMS-14C dates and correlated with varve chronology, OSL and 10Be dates.

  7. Magnetically Actuated Seal

    Science.gov (United States)

    Pinera, Alex

    2013-01-01

    This invention is a magnetically actuated seal in which either a single electromagnet, or multiple electromagnets, are used to control the seal's position. This system can either be an open/ close type of system or an actively controlled system.

  8. Magnetically Actuated Seal Project

    Data.gov (United States)

    National Aeronautics and Space Administration — FTT proposes development of a magnetically actuated dynamic seal. Dynamic seals are used throughout the turbopump in high-performance, pump-fed, liquid rocket...

  9. Turbomachine Interface Sealing

    Science.gov (United States)

    Hendricks, Robert C.; Chupp, Raymond E.; Lattime, Scott B.; Steinetz, Bruce M.

    2005-01-01

    Sealing interfaces and coatings, like lubricants, are sacrificial, giving up their integrity for the benefit of the component. Clearance control is a major issue in power systems turbomachine design and operational life. Sealing becomes the most cost-effective way to enhance system performance. Coatings, films, and combined use of both metals and ceramics play a major role in maintaining interface clearances in turbomachine sealing and component life. This paper focuses on conventional and innovative materials and design practices for sealing interfaces.

  10. Reduction of Baltic Sea Nutrient Inputs and Allocation of Abatement Costs Within the Baltic Sea Catchment

    OpenAIRE

    Wulff, Fred; Andersen, Hans Estrup; Blicher-Mathiesen, Gitte; Czajkowski, Mikolaj; Elofsson, Katarina; Fonnesbech-Wulff, Anders; Hasler, Berit; Humborg, Christoph; Hong, Bongghi; Jansons, Viestur; Mörth, Carl-Magnus; Thodsen, Hans; Smart, James C. R.; Smedberg, Erik; Stålnacke, Per

    2014-01-01

    The Baltic Sea Action Plan (BSAP) requires tools to simulate effects and costs of various nutrient abatement strategies. Hierarchically connected databases and models of the entire catchment have been created to allow decision makers to view scenarios via the decision support system NEST. Increased intensity in agriculture in transient countries would result in increased nutrient loads to the Baltic Sea, particularly from Poland, the Baltic States, and Russia. Nutrient retentions are high, wh...

  11. Seals For Cryogenic Turbomachines

    Science.gov (United States)

    Hendricks, Robert C.; Tam, L. T.; Braun, M. J.; Vlcek, B. L.

    1988-01-01

    Analysis considers effects of seals on stability. Report presents method of calculation of flows of cryogenic fluids through shaft seals. Key to stability is local average velocity in seal. Local average velocity strongly influenced by effects of inlet and outlet and injection of fluid.

  12. Fluid seals technology at BHR Group Ltd.

    Science.gov (United States)

    Leefe, Simon

    1991-01-01

    A mathematical model was developed for ESA, which couples the rigid body dynamics in four degrees of freedom of a flexibly mounted stator (with Coulomb damping) of a turbopump face seal with the fluid film behavior. The interfacial film is assumed gaseous, and the model incorporates laminar/turbulent flow, inertia and sonic choking. Seal faces may be wavy and coned, while the rotating ring can be eccentrically mounted, misaligned with the shaft and oscillate axially at arbitrary frequency. The model is currently being coded into software. An experimental program using a high speed cryogenic/hot gas test rig is being conducted to verify the output of the computer program.

  13. Low Cost, Durable Seal

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, George; Parsons, Jason; Friedman, Jake

    2010-12-17

    Seal durability is critical to achieving the 2010 DOE operational life goals for both stationary and transportation PEM fuel cell stacks. The seal material must be chemically and mechanically stable in an environment consisting of aggressive operating temperatures, humidified gases, and acidic membranes. The seal must also be producible at low cost. Currentlyused seal materials do not meet all these requirements. This project developed and demonstrated a high consistency hydrocarbon rubber seal material that was able to meet the DOE technical and cost targets. Significant emphasis was placed on characterization of the material and full scale molding demonstrations.

  14. Zero leakage sealings

    Science.gov (United States)

    Kotesovec, Bernhard; Steinrück, Herbert

    2010-11-01

    The piston rod of a reciprocating compressor is sealed with elastic cylindrical sealing elements. Across the sealings the pressure drops from the operating pressure to the ambient pressure. The lubrication gap between the elastic sealing and reciprocating piston rod is studied with the aim to find conditions of a leakage free sealing. The flow in the lubrication gap and the elastic deformation of the sealing are determined simultaneously. The net-flow during one cycle of the reciprocating piston rod is calculated. It turns out that maintaining zero leakage is very sensible. Indeed the outbound flow during out-stroke has to be equal the inbound flow during the in-stroke. By prescribing a special shape of the undeformed sealing zero leakage can be attained - at least theoretically for certain operating conditions. It turns out that temperature dependent material data and a model for cavitation is necessary. The model, its numerical implementation and results will be discussed.

  15. Jelektrojenergeticheskaja kooperacija v Baltijskom regione i rol' v nej Rossii [Electric energy cooperation in the Baltic Sea region and the role of Russia in it

    Directory of Open Access Journals (Sweden)

    Zverev Yuri

    2013-01-01

    Full Text Available This article examines cooperation in the electric energy sector in the Baltic region. The author explores the existing undersea HVDC power exchange projects. It is emphasised that cooperation in the electric energy sector is concentrated largely in the EU member states despite earlier plans to establish the Baltic energy ring, which would also include Russia and Belarus. The author stresses that one of the most acute problems for the EU today is overcoming isolation of the energy systems of the Baltic States (Lithuania, Latvia, and Estonia from that of the major part of the EU. This task has become especially relevant after the closing of the Ignalina NPP (Lithuania, which used to be the primary energy source for the three Baltic States. The article examines key projects of the construction of new international power transmission lines in the framework of the Baltic Energy Market Interconnection Plan (BEMIP and the prospects of the Visaginas NPP (Lithuania in solving energy problems of the Baltic States. The author analyses Russia’s role in the electric energy market and focuses on a possible increase of the country’s energy market share following the construction of the Baltic NPP and the export of generated electric energy to Poland, Lithuania, Germany, and Sweden. The author concludes that the prospects of Russia’s energy export to the Baltic Sea region will be determined not only by technological, economic and market factors, but rather by the general state of relations between Russia and the EU. Moreover, a lot depends on Lithuania’s decision on the construction of the Visaginas NPP, as well as the way the EU and the Baltic States solve the problem of energy supply in case the NPP project is terminated.

  16. The Costs of a Cleaner baltic Sea

    DEFF Research Database (Denmark)

    Brodersen, Sisse Liv; Konrad, Maria Theresia Hedegaard; Hasler, Berit;

    2009-01-01

    of the results was nutrient reduction targets for each country - the BSAP targets. Because the Baltic Sea is such an international marine area, receiving pollutants from many  countries, an international approach is necessary to make effective solutions. But is the BSAP the most cost-effective solution...... to the regulation of the Baltic Sea? And does the BSAP result in cost-effective reductions in the different countries, which is a requirement of the Water Framework Directive and the Marine Strategy Directive?   These questions are studied and answered using a cost minimisation model for the Baltic sea, initially...... the BSAP targets are set as target reductions for each countries.  The comparison reveals what the additional costs of fulfilling a political target for each country are instead pursuing a cost effective solution for the Baltic Sea.  In addition  we simulate cost minimising solutions for obtaining...

  17. Dynamic sealing principles

    Science.gov (United States)

    Zuk, J.

    1976-01-01

    The fundamental principles governing dynamic sealing operation are discussed. Different seals are described in terms of these principles. Despite the large variety of detailed construction, there appear to be some basic principles, or combinations of basic principles, by which all seals function, these are presented and discussed. Theoretical and practical considerations in the application of these principles are discussed. Advantages, disadvantages, limitations, and application examples of various conventional and special seals are presented. Fundamental equations governing liquid and gas flows in thin film seals, which enable leakage calculations to be made, are also presented. Concept of flow functions, application of Reynolds lubrication equation, and nonlubrication equation flow, friction and wear; and seal lubrication regimes are explained.

  18. Ring blowers. Ring blower

    Energy Technology Data Exchange (ETDEWEB)

    Nakahara, Y.; Okamura, T.; Takahashi, M. (Fuji Electric Co. Ltd., Tokyo (Japan))

    1991-06-10

    Features, structures and several products of ring blowers were outlined. The ring blower is featured by its medium characteristics because it is higher in air pressure than a turboblower and larger in airflow than a vane blower, and it is applicable flexibly to not only air blasting but various industrial fields such as suction transfer. As several products corresponding to various fields, the followings were outlined: the low noise type with optimum shapes of inlet, outlet and casing cover for reducing noises by 10 dB or more, the heat resistant, water-tight and explosion-proof types suitable for severe environmental conditions, the multi-voltage type for every country served at different voltages, the high air pressure type with two pressure rise stages, and the large airflow type with a wide impeller. In addition, as special use products, the glass fiber reinforced unsatulated polyester ring blower for respiration apparatus, and the variable speed blushless DC motor-driven one for medical beds were outlined. 2 refs., 9 figs., 1 tab.

  19. Applications of quantum message sealing

    CERN Document Server

    Worley, G G

    2005-01-01

    In 2003, Bechmann-Pasquinucci introduced the concept of quantum seals, a quantum analogue to wax seals used to close letters and envelopes. Since then, some improvements on the method have been found. We first review the current quantum sealing techniques, then introduce and discuss potential applications of quantum message sealing, and conclude with some discussion of the limitations of quantum seals.

  20. Repository seals requirements study

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-11-03

    The Yucca Mountain Site Characterization Project, managed by the Civilian Radioactive Waste Management System (CRWMS) Management and Operating Contractor (M and O) is conducting investigations to support the Viability Assessment and the License Application for a high-level nuclear waste repository at Yucca Mountain, Nevada. The sealing subsystem is part of the Yucca Mountain Waste Isolation System. The Yucca Mountain Site Characterization Project is currently evaluating the role of the sealing subsystem (shaft, ramp and exploratory borehole seals) in achieving the overall performance objectives for the Waste Isolation System. This report documents the results of those evaluations. This report presents the results of a repository sealing requirements study. Sealing is defined as the permanent closure of the shafts, ramps, and exploratory boreholes. Sealing includes those components that would reduce potential inflows above the repository, or that would divert flow near the repository horizon to allow vertical infiltration to below the repository. Sealing of such features as emplacement drifts was not done in this study because the current capability to calculate fracture flow into the drifts is not sufficiently mature. The objective of the study is to provide water or air flow performance based requirements for shafts, ramps, and exploratory boreholes located near the repository. Recommendations, as appropriate, are provided for developing plans, seals component testing, and other studies relating to sealing.

  1. Development of Mechanical Sealing and Laser Welding Technology to Instrument Thermocouple for Nuclear Fuel Test Rod

    Energy Technology Data Exchange (ETDEWEB)

    Joung, Chang-Young; Ahn, Sung-Ho; Hong, Jin-Tae; Kim, Ka-Hye; Huh, Sung-Ho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    Zircaloy-4 of the nuclear fuel test rod, AISI 316L of the mechanical sealing parts, and the MI (mineral insulated) cable at a thermocouple instrumentation are hetero-metals, and are difficult to weld to dissimilar materials. Therefore, a mechanical sealing method to instrument the thermocouple should be conducted using two kinds of sealing process as follows: One is a mechanical sealing process using Swagelok, which is composed of sealing components that consists of an end-cap, a seal tube, a compression ring and a Swagelok nut. The other is a laser welding process used to join a seal tube, and an MI cable, which are made of the same material. The mechanical sealing process should be sealed up with the mechanical contact compressed by the strength forced between a seal tube and an end-cap, and the laser welding process should be conducted to have no defects on the sealing area between a seal tube and an MI cable. Therefore, the mechanical sealing and laser welding techniques need to be developed to accurately measure the centerline temperature of the nuclear fuel test rod in an experimental reactor. The mechanical sealing and laser welding tests were conducted to develop the thermocouple instrumentation techniques for the nuclear fuel test rod. The optimum torque value of a Swagelok nut to seal the mechanical sealing part between the end-cap and seal tube was established through various torque tests using a torque wrench. The optimum laser welding conditions to seal the welding part between a seal tube and an MI cable were obtained through various welding tests using a laser welding system.

  2. High Test Peroxide High Sealing Conical Seal Project

    Data.gov (United States)

    National Aeronautics and Space Administration — High Test Peroxide (HTP) Highly Compatible High Sealing Conical Seals are necessary for ground test operations and space based applications. Current conical seals...

  3. SOME CONSIDERATIONS REGARDING ANALITICAL SOLVING OF THE REYNOLD’S EQUATION FROM FACE SEAL

    Directory of Open Access Journals (Sweden)

    Nicolae POPA

    2010-10-01

    Full Text Available Taking into consideration a mechanical face seal which runs in hydrodynamic duty, we intend to understand what’s going on under its surfaces. Until nowadays the experimental study to measure the parameters of film between two seal surfaces is very difficult. To explain these phenomena from this interface is necessary to know the theoretical pressures. The paper uses a primary seal model where the seal surfaces are considered with misalignment but the ring centre distance is constant. Considering some simplified hypothesis it determines the Reynold’s equation, it’s solving leading to the pressure equation of sealing interface.

  4. Frictional heat transfer regularity of the fluid film in mechanical seals

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The frictional heat transfer regularity in the mechanical seal system consisting of the rotating ring, the stationary ring, the fluid film in the end faces and the sealed medium was investigated. The primary factors affecting the frictional heat transfer regularity, such as the heat transfer coefficients from the rings to the sealed medium, the frictional heat flux, the frictional heat distribution ratio and so on, were discussed. The equations for calculating the temperature field both in the sealing members and in the fluid film were derived. The coupling analysis of the frictional heat of the fluid film and the thermal deformation of the two end faces of the rings was carried out to obtain the separation angle of the two deformed end faces in consideration of the viscosity change of the fluid film. The results indicate that the frictional heat of the fluid film heavily affects its characteristic and the sealing performance of mechanical seals. The frictional heat changes not only the shape of the gap between the end faces but also the viscosity of the fluid film, and thereupon leads to the increase of the leakage rate. The maximum temperature of the system is at the inner radius of the fluid film, and most of the frictional heat is conducted by the rotating ring. Based on the heat transfer analysis method put forward in this paper, the parameterized design of mechanical seals can be realized to determine the best geometrical parameters and to select the appropriate material of the sealing members.

  5. Saving Seal Cutting

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    On April 20, the graduation ceremony of China’s seal-cutting art postgraduates and visiting experts from the Institute of Seal Cutting Art under the China Art Academy was held in Beijing. On the same day, the exhibition of the works of the teachers and graduates of the institute was also held.

  6. Lunar nodal tide in the Baltic Sea

    Directory of Open Access Journals (Sweden)

    Andrzej Wróblewski

    2001-03-01

    Full Text Available The nodal tide in the Baltic Sea was studied on the basis of the Stockholm tide-gauge readings for 1825-1984; data from the tide gauge at Swinoujscie for the same period provided comparative material. The Stockholm readings are highly accurate and are considered representative of sea levels in the whole Baltic; hence, the final computations were performed for the readings from this particular tide gauge for the period 1888-1980. The tidal amplitude obtained from measurements uncorrected for atmospheric pressure or wind field was compared with that forced only by atmospheric effects. The amplitude of the recorded nodal tide was the same as the equilibrium tide amplitude calculated for Stockholm. Calculations for equilibrium tide amplitudes were also performed for the extreme latitudes of the Baltic basin.

  7. Status of the harbour seal (Phoca vitulina in Southern Scandinavia

    Directory of Open Access Journals (Sweden)

    Morten Tange Olsen

    2013-09-01

    Full Text Available The harbour seal population in Southern Scandinavia has experienced repeated declines caused by hunting and epizootics. These events have shaped the current distribution and abundance of the population. This paper assesses the current status of the population. We estimate trends in abundance of harbour seals from long term survey data, compare these with historic trends inferred from previously published material, and discuss past and potential threats to the harbour seal population of Southern Scandinavia. It is evident that harbour seals have disappeared from haulout areas along the Danish shores of Kattegat and in the westernmost part of the Baltic Sea, where they were previously numerous. In the 1920-30s, when abundance was at its lowest, the population is estimated to have been only a fraction of its original size. Following 30 years of protection the population is currently approaching historic abundance and might have reached the carrying capacity in some areas. Further development depends largely on effects of future epizootics, anthropogenic disturbance, and availability of suitable haulout sites.

  8. Vortex rings

    Energy Technology Data Exchange (ETDEWEB)

    Akhmetov, D.G. [Lavrentiev Institute of Hydrodynamics, Novosibirsk (Russian Federation)

    2009-07-01

    This book presents a comprehensive coverage of the wide field of vortex rings. The book presents the results of systematic experimental investigations, theoretical foundation, as well as the practical applications of vortex rings, such as the extinction of fires at gushing gas and oil wells. All the basic properties of vortex rings as well as their hydrodynamic structures are presented. Special attention is paid to the formation and motion of turbulent vortex rings. (orig.)

  9. Bio-engineering in the Baltic Sea

    DEFF Research Database (Denmark)

    Zandersen, Marianne

    2011-01-01

    Bio-engineering in the Baltic Sea – value of water quality improvements & risk perceptions Dr. Marianne Zandersen1 Department of Environmental Science, Aarhus University Abstract The Baltic Sea is heavily eutrofied and the trend has gone from bad to worse. The hypoxic zone has increased about 4...... of the water column to the bottom waters/deepwater. The expected effects include a slowing down of the sediment release from the bottom and improvement of the possibilities for aerobic bacterial decomposition and over time for the establishment of fauna. The projects test a bio-engineered approach to speeding...

  10. Bering-Okhotsk Seal Survey (BOSS) Identified Hot Spots (2012-13)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — US surveys were conducted of the Bering Sea pack ice for bearded, spotted, ribbon, and ringed seals using digital cameras and thermal imagers mounted in the belly...

  11. Bering-Okhotsk Seal Survey (BOSS) Color Imagery (2012-13)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — US surveys were conducted of the Bering Sea pack ice for bearded, spotted, ribbon, and ringed seals using digital cameras and thermal imagers mounted in the belly...

  12. On the normal stress effect in grease-lubricated bearing seals

    NARCIS (Netherlands)

    Baart, P.; Lugt, P.M.; Prakash, B.

    2014-01-01

    The film formation in lip seals, due to the non-Newtonian rheology of the lubricant, has been a topic of speculation. Earlier work suggests that normal stresses in grease would be favorable for the film buildup between the seal lip and shaft or bearing ring. In the current article, we evaluate this

  13. Ring theory

    CERN Document Server

    Rowen, Louis H

    1991-01-01

    This is an abridged edition of the author's previous two-volume work, Ring Theory, which concentrates on essential material for a general ring theory course while ommitting much of the material intended for ring theory specialists. It has been praised by reviewers:**""As a textbook for graduate students, Ring Theory joins the best....The experts will find several attractive and pleasant features in Ring Theory. The most noteworthy is the inclusion, usually in supplements and appendices, of many useful constructions which are hard to locate outside of the original sources....The audience of non

  14. Practical applicability and preliminary results of the Baltic Environmental Satellite Remote Sensing System (SatBaltic)

    Science.gov (United States)

    Wozniak, B.; Ostrowska, M.; Bradtke, K.; Darecki, M.; Dera, J.; Dudzinska-Nowak, J.; Dzierzbicka, L.; Ficek, D.; Furmanczyk, K.; Kowalewski, M.; Krezel, A.; Majchrowski, R.; Paszkuta, M.; Ston-Egiert, J.; Stramska, M.; Zapadka, T.

    2012-04-01

    SatBaltic (Satellite Monitoring of the Baltic Sea Environment) project is being realized in Poland by the SatBaltic Scientific Consortium, specifically appointed for this purpose, which associates four scientific institutions: the Institute of Oceanology PAN in Sopot - coordinator, the University of Gdańsk (Institute of Oceanography), the Pomeranian Academy in Słupsk (Institute of Physics) and the University of Szczecin (Institute of Marine Sciences). We present the first the results of the first year and a half of SatBaltic's implementation. The final result of the project is to be the creation and setting in motion of the SatBaltic Operational System (SBOS), the aim of which is to monitor effectively and comprehensively the state of the Baltic Sea environment using remote sensing techniques. Various aspects of the practical applicability of SBOS to the monitoring of the Baltic ecosystem are discussed. We present some examples of the maps of the various characteristics of the Baltic obtained using the current version of SBOS, including algorithms and models that are still in an unfinished state. At the current stage of research, these algorithms apply mainly to the characteristics of the solar energy influx and the distribution of this energy among the various processes taking place in the atmosphere-sea system, and also to the radiation balance of the sea surface, the irradiance conditions for photosynthesis and the condition of plant communities in the water, sea surface temperature distributions and some other marine phenomena correlated with this temperature. Also given are results of preliminary inspections of the accuracy of the magnitudes shown on the maps.

  15. Sealing device for providing a seal in a turbomachine

    Science.gov (United States)

    Lacy, Benjamin Paul; Kottilingam, Srikanth Chandrudu; Porter, Christopher Donald; Schick, David Edward; Weber, David Wayne

    2016-08-16

    Sealing device for providing seals between adjacent components, and turbomachines utilizing such sealing devices, are provided. A sealing device includes a seal plate insertable between the adjacent components, the seal plate comprising a first face and an opposing second face. The sealing device further includes a plurality of pins extending from one of the first face or the second face, the plurality of pins configured to space the one of the first face or the second face from contact surfaces of the adjacent components.

  16. Windpower and grey seals: An impact assessment of potential effects by sea-based windpower plants in a local seal population

    Energy Technology Data Exchange (ETDEWEB)

    Sundberg, Jan; Soederman, Malin [Uppsala Univ. (Sweden). Dept. of Animal Ecology

    2000-05-01

    The impact of five sea-based wind power plants on two haulout sites for grey seals on southwestern Gotland, in the Baltic Sea, was analysed. Data on seal numbers was collected on a regular basis during the initial stages of the project from summer 1996, continuing during the building (autumn 1997) and running of the wind power plants (from spring 1998) until the end of June 1999. Additional observational data from earlier years was also available. Indications of lower occurrence and reduced number of seals in the area was found during periods of time in 1997 and 1998, times of construction and active running of the plants. However, no evidence on the wind power plants, per se, affecting the grey seals was found. Instead, several weather factors were found to affect the number of seals in the area, and periods of low occurrence and number of seals were more likely explained by i.e. unfavourable water levels and hard wind from certain directions. One important, short term, impact factor was however found. Human induced disturbances such as boat and helicopter traffic, some which were directly related to maintenance of the wind power plants, temporarily reduced number of seals and made them more restless. Disturbance thus constitutes a potential threat to seals. A shift from one to the other of the two haulout sites was also noted, a shift which likely is due to disturbances. Future guidelines are given, including some restrictions in movements near the haulout sites. Continued observations and studies are suggested if more off-shore wind power plants will be raised in the area. A call for more stringent use of environmental impact assessments is thus made. Also, suggestions on measures to be taken in order to reduce the effect of human related disturbances are made. In order to create sustainable conditions for a continued population of seals in the area and in order to create opportunities for a reestablishment of the grey seal in the southern Baltic region

  17. CENTRIFUGAL PUMP AND SHAFT SEALING MEANS

    Science.gov (United States)

    Rushing, F.C.

    1960-09-01

    A description is given of sealing means between a hollow rotatable shaft and a stationary member surrounding the shaft which defines therewith a sealing space of annular cross-section, comprising a plurality of axially spaced rings held against seats by ring springs which serve to subdivide the sealing space- into a plurality of zones. Process gas introduced into the hollow shaft through a port communicating with a centrally located zone which iu turn communicates with a bore in the sleeve, is removed from the shaft through a second port communicating with an adjacent central zone and discharged through a second bore. A sealant gas is supplied to an end zone under a pressure sufficient to cause it to flow axially into adjacent zones and then maintained at a lower pressure than either the sealant gas source or the process gas inlet zone, preventing the sealant gas from entering the shaft and allowing gases leaking into the sealant gas to be withdrawn and led to a separator.

  18. Fur seal investigations, 1966

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Annually a report is made on the fur seal investigations carried on by the Bureau of Commercial Fisheries on the Pribilof Islands and at sea. Investigations on the...

  19. Ribbon Seal Distribution Map

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains GIS layers that depict the known spatial distributions (i.e., ranges) and reported breeding areas of ribbon seals (Histriophoca fasciata). It...

  20. Bearded Seal Distribution Map

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains GIS layers that depict the known spatial distributions (i.e., ranges) of the two subspecies of bearded seals (Erignathus barbatus). It was...

  1. Spotted Seal Distribution Map

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains GIS layers that depict the known spatial distributions (i.e., ranges) and reported breeding areas of spotted seals (Phoca largha). It was...

  2. Baltic air wars intensify / Dorian Ziedonis

    Index Scriptorium Estoniae

    Ziedonis, Dorian

    2008-01-01

    Leedu lennufirma FlyLAL pidi maksma ära 40 000 euro suuruse trahvi, et firma lennuk saaks Riia lennuväljalt lahkuda. Varem oli FlyLAL nõudnud Riia Lennujaamalt kompensatsiooni, kuna lennujaam oli võimaldanud Läti lennufirmal airBaltic maksta väiksemaid lennujaamatasusid

  3. Baltic Factor in Russia-France Relations

    Directory of Open Access Journals (Sweden)

    Maltsev Leonid A.

    2016-12-01

    Full Text Available The article aims to identify the role of the Baltic factor in Russia-France relations. Despite the fact that the Baltic Sea region (BSR no longer plays an important role in Russia-France bilateral relations, the authors attach significance to analysing the dynamics and changes of the BSR role in European politics in the post- Napoleonic period. The authors compare the Russian and the July Monarchies (1830—1848 in the context of the current Vienna system of international relations. The article describes the role of the 1830—1831 uprising in Poland, which was an event of particular importance. The monarchies of the two countries had to take into account new social phenomena, which were more pronounced in France. After the suppression of the uprising in the Polish part of the Russian Empire, Polish emigrants residing in France became the stumbling block for the development of Russia- France relations. The article explores the role of P. de Barante, Ambassador of France to Russia and describes France and Russia’s trade and economic interests in the Baltic Sea region. The authors conclude that the specificity of Russia-France bilateral relations became more apparent during the First and Second World Wars. However, the Baltic factor has lost its relevance over time.

  4. Seasonal variability in the Baltic Sea level

    Directory of Open Access Journals (Sweden)

    Marek Świrgoń

    2013-11-01

    Full Text Available Sea level is subject to spatial and temporal variability on different scales. In this paper we investigate seasonal variability in the open Baltic Sea level using daily satellite altimetry data for the period 1 January 1993-31 December 2010. Our results indicate that there is a well-pronounced seasonal cycle in the 18-year average sea level and in its standard deviation. The average annual SLA amplitude in the open Baltic Sea is about 18 cm. The seasonal cycle of the SLA in the Baltic Sea is asymmetric in shape. In the autumn and winter (about 240-260 days per year, the 18-year average daily SLA are higher than the 18-year annual average SLA. In the spring and summer (about 100-120 days per year, the 18-year average daily SLA are lower than the 18-year annual average SLA. A similar asymmetry of the seasonal cycle is not observed in the North Sea and North Atlantic SLA data. The annual pattern of the sea level variability in the Baltic Sea is evident if one considers multi-year average time series, but the cycle can be obscured in some years.

  5. Seeds of Failure in Colbert's Baltic Policy.

    Science.gov (United States)

    Mackey, Richard William

    1984-01-01

    This investigation of French mercantilist initiatives and policies in the seventeenth century focuses on the attempts of Colbert, the controller general of finance to Louis XIV, to stimulate French trade with the Baltic by establishing a Company of the North. (RM)

  6. Dissent and Nationalism in the Soviet Baltic.

    Science.gov (United States)

    1983-09-01

    it is neither exclusivist nor chauvinistic, and cooperation across national lines, particularly with other Baltic groups, is commonplace and effec... exclusivist or chauvinistic. Indeed, one of its trademarks has been an unflagging concern for the rights of other nations and a desire to coperate with

  7. Planetary Rings

    CERN Document Server

    Tiscareno, Matthew S

    2011-01-01

    Planetary rings are the only nearby astrophysical disks, and the only disks that have been investigated by spacecraft. Although there are significant differences between rings and other disks, chiefly the large planet/ring mass ratio that greatly enhances the flatness of rings (aspect ratios as small as 1e-7), understanding of disks in general can be enhanced by understanding the dynamical processes observed at close-range and in real-time in planetary rings. We review the known ring systems of the four giant planets, as well as the prospects for ring systems yet to be discovered. We then review planetary rings by type. The main rings of Saturn comprise our system's only dense broad disk and host many phenomena of general application to disks including spiral waves, gap formation, self-gravity wakes, viscous overstability and normal modes, impact clouds, and orbital evolution of embedded moons. Dense narrow rings are the primary natural laboratory for understanding shepherding and self-stability. Narrow dusty...

  8. INVESTIGATION INTO EFFECT OF SPRING PRESSURE ON PERFORMANCE OF BALANCED MECHANICAL SEALS

    Institute of Scientific and Technical Information of China (English)

    SUN Jianjun; GU Boqin

    2007-01-01

    The loads acting on the sealing elements of balanced mechanical seals are analyzed. When the balance factor approaches the back pressure factor, the spring pressure will become main part of the face pressure. The leakage model of balanced mechanical seals is established on the base of M-B model for rough surface. Several GY-70 type balanced mechanical seals are tested. The influences of the spring pressure both on the leakage rate and on the friction characteristic of balanced mechanical seals are investigated. The research results indicate that as spring pressure increases, both the clearance between two end faces and the leakage rate will decrease, and the friction will be more serious because lubrication medium between the rotating ring and the stationary ring reduces, though the increase of the spring pressure may not be enough to change the face friction state of mechanical seals. There exists an optimum spring pressure for mechanical seal operation. Under this spring pressure, not only leakage rate is small, but also the seal end surfaces have a fine friction characteristic.Under different operating conditions, identical type mechanical seals may possess different spring pressure. Appropriate selection of spring pressure is valuable to realize long-period and small leakage rate operating of balanced mechanical seals.

  9. Enantioselective gas chromatographic separation of methylsulfonyl PCBs in seal blubber, pelican muscle and human adipose tissues

    Energy Technology Data Exchange (ETDEWEB)

    Karasek, L.; Rosmus, J. [Veterinary Institute Prague (Czech Republic). Dept. of Chemistry; Hajslova, J. [Institute of Chemical Technology (Czech Republic). Dept. of Food Chemistry and Analysis; Huehnerfuss, H. [Hamburg Univ. (Germany). Inst. fuer Organische Chemie

    2004-09-15

    Methyl sulfone derivatives are known to represent primary metabolic products of PCBs (MeSO2- CB) and DDE (MeSO2-DDE). These metabolites are formed via mercapturic acid pathway and belong to persistent, lipophilic compounds which accumulate in the adipose, lung, liver and kidney tissues of mammals exposed to PCBs. In 1976 Jenssen and Jansson reported the identification of PCB methyl sulfones as metabolites of PCBs in Baltic grey seal blubber. Methyl sulfones are moderately polar compounds that are only slightly less hydrophobic than the parent PCBs, and their partition coefficients fulfill the requirements for bioaccumulation. The highest concentrations have been found in kidney and lung tissues of seals, otters, beluga whales, polar bears, fishes and in human tissues. In the present investigation two samples of seal blubber, two pelican muscles and eleven human adipose tissue samples were analysed with regard to their concentrations of PCB parent compounds as well as to the respective chiral methylsulfonyl metabolites.

  10. WEAR AND SEALING CHARACTERISTICS OF ENGINE VALVE GUIDE

    Institute of Scientific and Technical Information of China (English)

    Qu Shengguan; Xia Wei; Han Lifa; Xiao Zhiyu; Chen Weiping; Li Yuanyuan

    2005-01-01

    A novel powder metallurgy (P/M) material with high wear resistance is developed in order to decrease the wear and lubricant-leakage of a diesel engine valve guide. The friction and wear tests of this material are conducted. It indicates that the wear resistance of the newly developed P/M material has been improved and much better than that of the formerly used alloy steel. Moreover, three different sealing structures are designed and theoretically analyzed with respect to the characteristic of hydrodynamic sealing. Through comparative experiments of component leakage and engine run-in for different valve guide structures, it proves that the structure with a machined sealing groove but not installed with a seal-ring cannot only reduce the specific lubricant consumption (SLC) of cylinder head, but also decrease the wear of valve stem and valve guide.

  11. THE ORIGINS OF SEALS AND SEALING IN CHINA

    Institute of Scientific and Technical Information of China (English)

    1994-01-01

    The origin of Chinese seals remains obscure in modern research. Most publications, influenced by the traditional point of view, have dealt with the seals handed down from the Eastern Zhou (771-256 B.C.). Only a few studies have discussed seals from their earliest-and still neglected-history. There have even been some suggestions, based on the idea of using a seal and using it on clay first developed in Mesopotamia, that the seal was introduced to China from the Near East. This proposed foreign origin makes the history of Chinese seals more complicated.

  12. Harbour porpoise Phocoena phocoena abundance in the southwestern Baltic Sea

    OpenAIRE

    Scheidat, M.; Gilles, A.; Kock, K. H.; Siebert, U

    2008-01-01

    Harbour porpoise Phocoena phocoena is the only cetacean species resident in the Baltic Sea. At least 2 different subpopulations occur in this area, with a presumed demarcation line in the western Baltic Sea. Aerial surveys were conducted during different seasons in the years 2002 to 2006, to obtain estimates of porpoise abundance for the southwestern Baltic. Within the survey area, 3 strata were defined. In total, 46 surveys were completed for these strata. Abundance estimates and correspondi...

  13. Suitability of otolith microchemistry for stock separation of Baltic cod

    DEFF Research Database (Denmark)

    Heidemann, F; Marohn, L; Hinrichsen, HH

    2012-01-01

    differences between individuals from the eastern and the western Baltic Sea and between North Sea and Baltic Sea samples. Sr/Ca, Ba/Ca, Y/Ca, Mg/Ca, Zr/Ca and Mn/Ca ratios had the strongest discriminatory power. A further separation of individuals caught in 3 different spawning grounds of the eastern Baltic......, however, was not possible. Elemental compositions from the core regions of otoliths from young of the year cod caught in eastern and western Baltic Sea spawning grounds showed significant differences in Sr/Ca, Ba/Ca and Mg/Ca concentrations. Analyses of similarities again showed significant differences...

  14. Identification of gymnodimine D and presence of gymnodimine variants in the dinoflagellate Alexandrium ostenfeldii from the Baltic Sea.

    Science.gov (United States)

    Harju, Kirsi; Koskela, Harri; Kremp, Anke; Suikkanen, Sanna; de la Iglesia, Pablo; Miles, Christopher O; Krock, Bernd; Vanninen, Paula

    2016-03-15

    Gymnodimines are lipophilic toxins produced by the marine dinoflagellates Karenia selliformis and Alexandrium ostenfeldii. Currently four gymnodimine analogues are known and characterized. Here we describe a novel gymnodimine and a range of gymnodimine related compounds found in an A. ostenfeldii isolate from the northern Baltic Sea. Gymnodimine D (1) was extracted and purified from clonal cultures, and characterized by liquid chromatography-tandem mass spectrometry (LC-MS/MS), nuclear magnetic resonance (NMR) spectroscopy, and liquid chromatography-high resolution mass spectrometry (LC-HRMS) experiments. The structure of 1 is related to known gymnodimines (2-5) with a six-membered cyclic imine ring and several other fragments typical of gymnodimines. However, the carbon chain in the gymnodimine macrocyclic ring differs from the known gymnodimines in having two tetrahydrofuran rings in the macrocyclic ring.

  15. Biotope map of the German Baltic Sea.

    Science.gov (United States)

    Schiele, Kerstin S; Darr, Alexander; Zettler, Michael L; Friedland, René; Tauber, Franz; von Weber, Mario; Voss, Joachim

    2015-07-15

    Full-coverage maps on the distribution of marine biotopes are a necessary basis for Nature Conservation and Marine Spatial Planning. Yet biotope maps do not exist in many regions. We are generating the first full-coverage biotope map for the German Baltic Sea according to the HELCOM Underwater biotope and habitat classification system (HUB). Species distribution modelling is applied to create full-coverage spatial information of biological features. The results of biomass modelling of twelve target taxa and presence/absence modelling of three target taxa enabled the identification of biological levels up to HUB level 6. Environmental data on bathymetry, light penetration depth and substrate are used to identify habitat levels. HUB biotope levels were combined with HUB habitat levels to create a biotope map. Altogether, 68 HUB biotopes are identified in the German Baltic Sea. The new biotope map combining substrate characteristics and biological communities will facilitate marine management in the area.

  16. Reduction of Baltic Sea nutrient inputs and allocation of abatement costs within the Baltic Sea catchment.

    Science.gov (United States)

    Wulff, Fredrik; Humborg, Christoph; Andersen, Hans Estrup; Blicher-Mathiesen, Gitte; Czajkowski, Mikołaj; Elofsson, Katarina; Fonnesbech-Wulff, Anders; Hasler, Berit; Hong, Bongghi; Jansons, Viesturs; Mörth, Carl-Magnus; Smart, James C R; Smedberg, Erik; Stålnacke, Per; Swaney, Dennis P; Thodsen, Hans; Was, Adam; Zylicz, Tomasz

    2014-02-01

    The Baltic Sea Action Plan (BSAP) requires tools to simulate effects and costs of various nutrient abatement strategies. Hierarchically connected databases and models of the entire catchment have been created to allow decision makers to view scenarios via the decision support system NEST. Increased intensity in agriculture in transient countries would result in increased nutrient loads to the Baltic Sea, particularly from Poland, the Baltic States, and Russia. Nutrient retentions are high, which means that the nutrient reduction goals of 135 000 tons N and 15 000 tons P, as formulated in the BSAP from 2007, correspond to a reduction in nutrient loadings to watersheds by 675 000 tons N and 158 000 tons P. A cost-minimization model was used to allocate nutrient reductions to measures and countries where the costs for reducing loads are low. The minimum annual cost to meet BSAP basin targets is estimated to 4.7 billion Euro.

  17. Sealing coupling. [LMFBR

    Science.gov (United States)

    Pardini, J.A.; Brubaker, R.C.; Rusnak, J.J.

    1982-09-20

    Disclosed is a remotely operable releasable sealing coupling which provides fluid-tight joinder of upper and a lower conduit sections. Each conduit section has a concave conical sealing surface adjacent its end portion. A tubular sleeve having convex spherical ends is inserted between the conduit ends to form line contact with the concave conical end portions. An inwardly projecting lip located at one end of the sleeve cooperates with a retaining collar formed on the upper pipe end to provide swivel capture for the sleeve. The upper conduit section also includes a tapered lower end portion which engages the inside surface of the sleeve to limit misalignment of the connected conduit sections.

  18. New airBaltic owner on board

    Index Scriptorium Estoniae

    2011-01-01

    Transatlantic Holdings Company on ostnud 9,6 miljoni euro eest 59 110 airBalticu aktsiat. Läti majandusminister Artis Kampars soovib raskustesse sattunud lennufirma juhi Bertolt Flicki väljavahetamist. airBaltic plaanib koondamist. Riigikogu liige Arto Aas rõhutas, et airBalticu kadumine turult ei ole Eesti reisijate huvides, kuna ta on suuruselt kolmas lennukompanii Tallinna Lennujaamas

  19. Host size-dependent anisakid infection in Baltic cod Gadus morhua associated with differential food preferences

    DEFF Research Database (Denmark)

    Zuo, Shaozhi; Huwer, Bastian; Bahlool, Qusay;

    2016-01-01

    A significant increase in the infection level of Baltic cod Gadus morhua with the anisakid nematode larvae Contracaecum osculatum and Pseudoterranova decipiens has been recorded during recent years due to the expanding local population of grey seals Halichoerus grypus, which act as final hosts fo....... One cannot exclude the possibility that the size-dependent C. osculatum infection of cod may contribute (indirectly or directly) to the differential mortality of larger cod (>38 cm) compared to smaller cod (...... sarsi) are preferred food items by small cod, the isopod Saduria entomon is taken by all size classes, and sprat Sprattus sprattus are common prey items for cod larger than 30 cm. Parasitological investigations (microscopic and molecular analyses) of H. sarsi (100 specimens) and S. entomon (40 specimens...

  20. SUPRAMITRAL RING

    Directory of Open Access Journals (Sweden)

    Rajesh G

    2011-11-01

    Full Text Available Supra mitral ring is a rare cause for congenital mitral valve obstr uction. The reported incidence of supramitral ring is 0.2-0.4% in general population and 8% in patients with congenital mitral valve disease. The condition is characterized by an abnormal ridge of connective tissue often circumferential in shape ,on the atrial side of the mitral valve encroaching on the orifice of the mitral valve. It may adhere to the leaflets of the valve and restrict their movements. Although a supramitral ring may be rarely nonobstructive, it often results in mitral valve inflow obstruction.

  1. Vacuum encapsulated hermetically sealed diamond amplified cathode capsule and method for making same

    Science.gov (United States)

    Rao, Triveni; Walsh, John; Gangone, Elizabeth

    2014-12-30

    A vacuum encapsulated, hermetically sealed cathode capsule for generating an electron beam of secondary electrons, which generally includes a cathode element having a primary emission surface adapted to emit primary electrons, an annular insulating spacer, a diamond window element comprising a diamond material and having a secondary emission surface adapted to emit secondary electrons in response to primary electrons impinging on the diamond window element, a first cold-weld ring disposed between the cathode element and the annular insulating spacer and a second cold-weld ring disposed between the annular insulating spacer and the diamond window element. The cathode capsule is formed by a vacuum cold-weld process such that the first cold-weld ring forms a hermetical seal between the cathode element and the annular insulating spacer and the second cold-weld ring forms a hermetical seal between the annular spacer and the diamond window element whereby a vacuum encapsulated chamber is formed within the capsule.

  2. Determinantal rings

    CERN Document Server

    Bruns, Winfried

    1988-01-01

    Determinantal rings and varieties have been a central topic of commutative algebra and algebraic geometry. Their study has attracted many prominent researchers and has motivated the creation of theories which may now be considered part of general commutative ring theory. The book gives a first coherent treatment of the structure of determinantal rings. The main approach is via the theory of algebras with straightening law. This approach suggest (and is simplified by) the simultaneous treatment of the Schubert subvarieties of Grassmannian. Other methods have not been neglected, however. Principal radical systems are discussed in detail, and one section is devoted to each of invariant and representation theory. While the book is primarily a research monograph, it serves also as a reference source and the reader requires only the basics of commutative algebra together with some supplementary material found in the appendix. The text may be useful for seminars following a course in commutative ring theory since a ...

  3. GOLD PRESSURE VESSEL SEAL

    Science.gov (United States)

    Smith, A.E.

    1963-11-26

    An improved seal between the piston and die member of a piston-cylinder type pressure vessel is presented. A layer of gold, of sufficient thickness to provide an interference fit between the piston and die member, is plated on the contacting surface of at least one of the members. (AEC)

  4. Mechanical Face Seal Dynamics.

    Science.gov (United States)

    1985-12-01

    These liquids range from lubricants to highly toxic chemicals and acids. The applications range from helicopter transmissions to nuclear reactor... Analit ~is., N ,iontat ting lame St-ak"ts fnn. ASXIE namin Behaioir ni Nonmmuiam ing (knied-Fate Mechanikal Seals:* SL /I ub In h. 104. 1. 111 *)6ii-414

  5. Ceramic to metal seal

    Energy Technology Data Exchange (ETDEWEB)

    Snow, Gary S. (Albuquerque, NM); Wilcox, Paul D. (Albuquerque, NM)

    1976-01-01

    Providing a high strength, hermetic ceramic to metal seal by essentially heating a wire-like metal gasket and a ceramic member, which have been chemically cleaned, while simultaneously deforming from about 50 to 95 percent the metal gasket against the ceramic member at a temperature of about 30 to 75 percent of the melting temperature of the metal gasket.

  6. Detection of grey seal

    NARCIS (Netherlands)

    van Bleijswijk, J.; Begeman, L.; Witte, H.J.; IJsseldijk, L.L.; Brasseur, S.M.J.M.; Gröne, A.; Leopold, M.F.

    2014-01-01

    DNA was analysed from external wounds on 3 dead harbour porpoises Phocoena phocoena that were stranded in the Netherlands. Puncture wounds as well as the edges of large open wounds were sampled with sterile cotton swabs. With specific primers that target the mtDNA control region of grey seal Halicho

  7. Cave Rings

    Science.gov (United States)

    2010-10-13

    hypothesis, that cave rings are formed in the same manner as coffee rings[3], that is, due to the enhanced deposition at the edges of sessile drops ...ring’ is the deposit formed when a sessile drop of a solution containing dissolved particles, such as coffee or salt, dries. This was investigated by...who expanded on Deegan et al.[3] to find an exact form for the evaporation flux over a sessile drop . It turns out that solving 179 for the flux is

  8. Multimission satellite altimetric data validation in the Baltic Sea

    DEFF Research Database (Denmark)

    Cheng, Yongcun; Andersen, Ole Baltazar; Knudsen, Per;

    2014-01-01

    The assessment of altimetric data is crucial for investigating the regional sea level variability. Few works has been performed to validate the altimetric data [1, 2] in the Baltic Sea. The exploring of multi-mission altimetric data in the Baltic Sea has yet to be published. The number of available...

  9. IODP expedition 347: Baltic Sea basin paleoenvironment and biosphere

    NARCIS (Netherlands)

    Andrén, T.; Barker Jorgensen, B.; Cotterill, C.; Green, S.; Slomp, C.

    2015-01-01

    The Integrated Ocean Drilling Program (IODP) expedition 347 cored sediments from different settings of the Baltic Sea covering the last glacial–interglacial cycle. The main aim was to study the geological development of the Baltic Sea in relation to the extreme climate variability of the region with

  10. Rationale for restocking the Eastern Baltic cod stock

    DEFF Research Database (Denmark)

    Støttrup, Josianne; Overton, Julia Lynne; Paulsen, Helge;

    2008-01-01

    The Danish Institute for Fisheries Research and Bornholm's Salmon Hatchery examined the potential for restocking Baltic cod (Gadus morhua callarias L.) in the eastern Baltic Sea. This cod population has adapted to the unique brackish water conditions where successful spawning depends on regular i...

  11. BALCOFISH - a BONUS+ project in the Baltic Sea

    DEFF Research Database (Denmark)

    Strand, Jakob

    The project BALCOFISH, acronym for "Integration of pollutant gene responses and fish ecology in Baltic coastal fisheries and management" is a newly started 3-years BONUS+-project funded by Baltic Organisations Network for Funding Science EEIG (www.bonusportal.org) with focus on contaminants...

  12. Oceanographic influences on the distribution of Baltic cod, Gadus morhua , during spawning in the Bornholm Basin of the Baltic Sea

    DEFF Research Database (Denmark)

    Tomkiewicz, Jonna; Lehmann, K.M.; St. John, Michael

    1998-01-01

    The Baltic Sea is a stratified, semi-enclosed sea typified by a low-salinity surface layer and a deep saline layer of varying volume, salinity, temperature and oxygen concentration. The relationships between these oceanographic factors and the distribution of Baltic cod are presented, utilizing r...... catchability and thereby the assessment and exploitation patterns of this stock...

  13. Seals Having Textured Portions for Protection in Space Environments

    Science.gov (United States)

    Daniels, Christopher (Inventor); Garafolo, Nicholas (Inventor)

    2016-01-01

    A sealing construct for a space environment includes a seal-bearing object, a seal on the seal-bearing object, and a seal-engaging object. The seal includes a seal body having a sealing surface, and a textured pattern at the sealing surface, the textured pattern defining at least one shaded channel surface. The seal-engaging object is selectively engaged with the seal-bearing object through the seal. The seal-engaging object has a sealing surface, wherein, when the seal-engaging object is selectively engaged with the seal-bearing object, the sealing surface of the seal-engaging object engages the sealing surface of the seal, and the seal is compressed between the seal-bearing object and the seal-engaging object such that at least one shaded channel surface engages the sealing surface of the seal-engaging object.

  14. Regenerator cross arm seal assembly

    Science.gov (United States)

    Jackman, Anthony V.

    1988-01-01

    A seal assembly for disposition between a cross arm on a gas turbine engine block and a regenerator disc, the seal assembly including a platform coextensive with the cross arm, a seal and wear layer sealingly and slidingly engaging the regenerator disc, a porous and compliant support layer between the platform and the seal and wear layer porous enough to permit flow of cooling air therethrough and compliant to accommodate relative thermal growth and distortion, a dike between the seal and wear layer and the platform for preventing cross flow through the support layer between engine exhaust and pressurized air passages, and air diversion passages for directing unregenerated pressurized air through the support layer to cool the seal and wear layer and then back into the flow of regenerated pressurized air.

  15. The Baltic Klint beneath the central Baltic Sea and its comparison with the North Estonian Klint

    Science.gov (United States)

    Tuuling, Igor; Flodén, Tom

    2016-06-01

    Along its contact with the Baltic Shield, the margin of the East European Platform reveals a well-developed, flooded terraced relief. The most striking and consistent set of escarpments at the contact of the Lower Palaeozoic calcareous and terrigenous rocks, known as the Baltic Klint (BK), extends from northwest of Russia to the Swedish island of Öland. Marine seismic reflection profiling in 1990-2004 revealed the central Baltic Sea Klint (BSK) section in detail and enabled comparison of its geology/geomorphology with a classical klint-section onshore, namely the North Estonian Klint (NEK). The conception of the BK onshore, which is based on the land-sea separating terraced relief in northern Estonia, is not fully applicable beneath the sea. Therefore, we consider that the BSK includes the entire terraced Cambrian outcrop. We suggest the term "Baltic Klint Complex" to include the well-terraced margin of the Ordovician limestone outcrop, which is weakly developed in Estonia. Because of a steady lithological framework of the bedrock layers across the southern slope of the Fennoscandian Shield, the central BSK in the western and the NEK in the eastern part of the Baltic Homocline have largely identical morphologies. The North Estonian Ordovician limestone plateau with the calcareous crest of the BK extends across the central Baltic Sea, whereas morphological changes/variations along the Klint base occur due to the east-westerly lithostratigraphic/thickness changes in the siliciclastic Cambrian sequence. The verge of the NEK, located some 30-50 m above sea level, starts to drop in altitude as its east-westerly course turns to northeast-southwest in western Estonia. Further westwards, the BK shifts gradually into southerly deepening (0.1-0.2°) layers as its crest drops to c. 150 m below sea level (b.s.l.) near Gotska Sandön. This course change is accompanied by a considerable decrease in thickness of the platform sedimentary cover, as below the central Baltic Sea the

  16. Sealing the Mitochondrial Respirasome

    OpenAIRE

    Winge, Dennis R.

    2012-01-01

    The mitochondrial respiratory chain is organized within an array of supercomplexes that function to minimize the generation of reactive oxygen species (ROS) during electron transfer reactions. Structural models of supercomplexes are now known. Another recent advance is the discovery of non-OXPHOS complex proteins that appear to adhere to and seal the individual respiratory complexes to form stable assemblages that prevent electron leakage. This review highlights recent advances in our underst...

  17. A sealing element

    Energy Technology Data Exchange (ETDEWEB)

    Obi, F.; Takada, K.

    1983-09-22

    A sealing lining made of a mixture of polyethylene or polypropylene with an additive which prevents destruction of the lining is used in the element. The content of the additive in the mixture is 10 to 30 percent by mass. The additive basically consists of polyethylene. Carboxyl groups are introduced into the polymer as an anion and sodium, potassium and molybdenum are introduced as the cation.

  18. Topological rings

    CERN Document Server

    Warner, S

    1993-01-01

    This text brings the reader to the frontiers of current research in topological rings. The exercises illustrate many results and theorems while a comprehensive bibliography is also included. The book is aimed at those readers acquainted with some very basic point-set topology and algebra, as normally presented in semester courses at the beginning graduate level or even at the advanced undergraduate level. Familiarity with Hausdorff, metric, compact and locally compact spaces and basic properties of continuous functions, also with groups, rings, fields, vector spaces and modules, and with Zorn''s Lemma, is also expected.

  19. Astaxanthin dynamics in Baltic Sea mesozooplankton communities

    Science.gov (United States)

    Snoeijs, Pauline; Häubner, Norbert

    2014-01-01

    The red pigment astaxanthin is a powerful antioxidant, which occurs in eggs and body tissues of crustaceans and fish. It is produced by crustaceans from algal carotenoids. In a two-year field study we assessed natural concentrations and dynamics of astaxanthin in mesozooplankton communities in the brackish Baltic Sea area. Astaxanthin levels varied between 0.37 and 36 ng L- 1. They increased with salinity along the Baltic Sea gradient and were linked to zooplankton biomass and phytoplankton community composition. Astaxanthin concentrations showed typical seasonal patterns and varied from 0.2 to 5.1 ng ind- 1, 0.2 to 3.4 ng (μg C)- 1 and 6 to 100 ng mm- 3. These concentrations were inversely related to water temperature and strongly linked to zooplankton community composition. Communities dominated by the calanoid copepods Temora longicornis, Pseudocalanus acuspes and Eurytemora spp. generally held the highest concentrations. With increasing cladocerans:copepods biomass ratios community astaxanthin concentrations decreased and with higher relative biomass of Acartia spp. the proportion of astaxanthin diesters decreased. Diesters prevailed in the cold season and they are thought to improve the antioxidant protection of storage lipids during winter. Climate change causes higher temperature and lower salinity in the Baltic Sea proper. This modifies zooplankton community composition, but not necessarily into a community with lower concentrations of astaxanthin since T. longicornis (high concentrations) has been reported to increase with higher temperature. However, decreased astaxanthin production in the ecosystem is expected if a basin-wide increase in the cladocerans:copepods biomass ratios would occur with further climate change.

  20. Navy GTE seal development activity

    Science.gov (United States)

    Grala, Carl P.

    1993-10-01

    Under the auspices of the Integrated High Performance Turbine Engine Technology Initiative, the Naval Air Warfare Center conducts advanced development programs for demonstration in the next generation of air-breathing propulsion systems. Among the target technologies are gas path and lube oil seals. Two development efforts currently being managed by NAWCAD are the High Performance Compressor Discharge Film-Riding Face Seal and the Subsonic Core High Speed Air/Oil Seal. The High Performance Compressor Discharge Film-Riding Face Seal Program aims at reducing parasitic leakage through application of a film-riding face sea concept to the compressor discharge location of a Phase 2 IHPTET engine. An order-of-magnitude leakage reduction relative to current labyrinth seal configurations is expected. Performance goals for these seals are (1) 1200 F air temperature, (2) 800 feet-per-second surface velocity, and (3) 600 SPI differential pressure. The two designs chosen for fabrication and rig test are a spiral groove and a Rayleigh step seal. Rig testing is currently underway. The Subsonic Core High Speed Air/Oil Seal Program is developing shaft-to-ground seals for next-generation propulsion systems that will minimize leakage and provide full life. Significantly higher rotor speeds and temperatures will be experienced. Technologies being exploited include, hydrodynamic lift assist features, ultra light weight designs, and improved cooling schemes. Parametric testing has been completed; a final seal design is entering the endurance test phase.

  1. TECHNOLOGY ROADMAPPING FOR IAEA SEALS.

    Energy Technology Data Exchange (ETDEWEB)

    HOFFHEINS,B.; ANNESE,C.; GOODMAN,M.; OCONNOR,W.; GUSHUE,S.; PEPPER,S.

    2003-07-13

    In the fall of 2002, the U.S. Support Program (USSP) initiated an effort to define a strategy or ''roadmap'' for future seals technologies and to develop a generalized process for planning safeguards equipment development, which includes seals and other safeguards equipment. The underlying objectives of the USSP include becoming more proactive than reactive in addressing safeguards equipment needs, helping the IAEA to maintain an inventory of cost-effective, reliable, and effective safeguards equipment, establishing a long-term planning horizon, and securing IAEA ownership in the process of effective requirements definition and timely transitioning of new or improved systems for IAEA use. At an initial workshop, seals, their functions, performance issues, and future embodiments were discussed in the following order: adhesive seals, metal seals, passive and active loop seals, ultrasonic seals, tamper indicating enclosures (including sample containers, equipment enclosures, and conduits). Suggested improvements to these technologies focused largely on a few themes: (1) The seals must be applied quickly, easily, and correctly; (2) Seals and their associated equipment should not unduly add bulk or weight to the inspectors load; (3) Rapid, in-situ verifiability of seals is desirable; and (4) Seal systems for high risk or high value applications should have two-way, remote communications. Based upon these observations and other insights, the participants constructed a skeletal approach for seals technology planning. The process begins with a top-level review of the fundamental safeguards requirements and extraction of required system features, which is followed by analysis of suitable technologies and identification of technology gaps, and finally by development of a planning schedule for system improvements and new technology integration. Development of a comprehensive procedure will require the partnership and participation of the IAEA. The

  2. Closure and Sealing Design Calculation

    Energy Technology Data Exchange (ETDEWEB)

    T. Lahnalampi; J. Case

    2005-08-26

    The purpose of the ''Closure and Sealing Design Calculation'' is to illustrate closure and sealing methods for sealing shafts, ramps, and identify boreholes that require sealing in order to limit the potential of water infiltration. In addition, this calculation will provide a description of the magma that can reduce the consequences of an igneous event intersecting the repository. This calculation will also include a listing of the project requirements related to closure and sealing. The scope of this calculation is to: summarize applicable project requirements and codes relating to backfilling nonemplacement openings, removal of uncommitted materials from the subsurface, installation of drip shields, and erecting monuments; compile an inventory of boreholes that are found in the area of the subsurface repository; describe the magma bulkhead feature and location; and include figures for the proposed shaft and ramp seals. The objective of this calculation is to: categorize the boreholes for sealing by depth and proximity to the subsurface repository; develop drawing figures which show the location and geometry for the magma bulkhead; include the shaft seal figures and a proposed construction sequence; and include the ramp seal figure and a proposed construction sequence. The intent of this closure and sealing calculation is to support the License Application by providing a description of the closure and sealing methods for the Safety Analysis Report. The closure and sealing calculation will also provide input for Post Closure Activities by describing the location of the magma bulkhead. This calculation is limited to describing the final configuration of the sealing and backfill systems for the underground area. The methods and procedures used to place the backfill and remove uncommitted materials (such as concrete) from the repository and detailed design of the magma bulkhead will be the subject of separate analyses or calculations. Post

  3. The Baltic policy of Germany and current international relations

    Directory of Open Access Journals (Sweden)

    Salikov Aleksey

    2016-03-01

    Full Text Available This article analyses the Baltic policy of united Germany from the 1990s until today. The authors set out to identify the significance of German-Baltic relations and the role of the Eastern policy in Russian-German relations. The method of dynamic comparison between the political and economic narrative in intergovernmental relations makes it possible to identify distinctive features of Germany’s Baltic policy in the context of current international relations. In particular, it is noted that Germany was most active in the Baltic region in the 1990s, when the country was establishing political, economic, and cultural ties with the new independent states. In the second half of the 1990s, Germany’s foreign policy became less intense. After the accession of Lithuania, Latvia, and Estonia to the EU and NATO in 2004, certain disagreements started to arise between Germany and the Baltics. It explains the lukewarm relations between them. The Ukraine events brought about a change in Germany’s regional policy. Despite Russia remaining one of the key economic and political counteractors, Germany, being a partner of the Baltics in the EU and NATO, cannot adopt a neutral position in the conflict of interests between the Baltics and Russia.

  4. Ring interferometry

    CERN Document Server

    Malykin, Grigorii B; Zhurov, Alexei

    2013-01-01

    This monograph is devoted to the creation of a comprehensive formalism for quantitative description of polarized modes' linear interaction in modern single-mode optic fibers. The theory of random connections between polarized modes, developed in the monograph, allows calculations of the zero shift deviations for a fiber ring interferometer. The monograph addresses also the

  5. Analysing Sovereign Credit Default Swaps of Baltic Countries

    Directory of Open Access Journals (Sweden)

    Arvydas Kregzde

    2015-06-01

    Full Text Available The paper analyses development of the Baltic sovereign CDS market. The level of commonalities and differences in credit risk of the Baltic countries with regard to CDS spreads is investigated. We apply principal component analysis, regression analysis, correlation analysis methods and Granger causality test. Driving forces for changes of CDS spreads in the individual country are established. We discover that the main impact of CDS spread changes arrives from external sources. Our study reveals interdependence between CDS spreads of the Baltic countries and analyses a contagion effect of the change of CDS spreads.

  6. Migration waves to the Baltic Sea region.

    Science.gov (United States)

    Lappalainen, T; Laitinen, V; Salmela, E; Andersen, P; Huoponen, K; Savontaus, M-L; Lahermo, P

    2008-05-01

    In this study, the population history of the Baltic Sea region, known to be affected by a variety of migrations and genetic barriers, was analyzed using both mitochondrial DNA and Y-chromosomal data. Over 1200 samples from Finland, Sweden, Karelia, Estonia, Setoland, Latvia and Lithuania were genotyped for 18 Y-chromosomal biallelic polymorphisms and 9 STRs, in addition to analyzing 17 coding region polymorphisms and the HVS1 region from the mtDNA. It was shown that the populations surrounding the Baltic Sea are genetically similar, which suggests that it has been an important route not only for cultural transmission but also for population migration. However, many of the migrations affecting the area from Central Europe, the Volga-Ural region and from Slavic populations have had a quantitatively different impact on the populations, and, furthermore, the effects of genetic drift have increased the differences between populations especially in the north. The possible explanations for the high frequencies of several haplogroups with an origin in the Iberian refugia (H1, U5b, I1a) are also discussed.

  7. On SAP-rings

    OpenAIRE

    Zhixiang, Wu

    2006-01-01

    The rings whose simple right modules are absolutely pure are called right $SAP$-rings. We give a new characterization of right $SAP$ rings, right $V$ rings, and von Neumann regular rings. We also obtain a new decomposition theory of right selfinjective von Neumann regular rings. The relationships between $SAP$-rings, $V$-rings, and von Neumann regular rings are explored. Some recent results obtained by Faith are generalized and the results of Wu-Xia are strengthened.

  8. Testing of molded high temperature plastic actuator road seals for use in advanced aircraft hydraulic systems

    Science.gov (United States)

    Waterman, A. W.; Huxford, R. L.; Nelson, W. G.

    1976-01-01

    Molded high temperature plastic first and second stage rod seal elements were evaluated in seal assemblies to determine performance characteristics. These characteristics were compared with the performance of machined seal elements. The 6.35 cm second stage Chevron seal assembly was tested using molded Chevrons fabricated from five molding materials. Impulse screening tests conducted over a range of 311 K to 478 K revealed thermal setting deficiencies in the aromatic polyimide molding materials. Seal elements fabricated from aromatic copolyester materials structurally failed during impulse cycle calibration. Endurance testing of 3.85 million cycles at 450 K using MIL-H-83283 fluid showed poorer seal performance with the unfilled aromatic polyimide material than had been attained with seals machined from Vespel SP-21 material. The 6.35 cm first stage step-cut compression loaded seal ring fabricated from copolyester injection molding material failed structurally during impulse cycle calibration. Molding of complex shape rod seals was shown to be a potentially controllable technique, but additional molding material property testing is recommended.

  9. Sealing the mitochondrial respirasome.

    Science.gov (United States)

    Winge, Dennis R

    2012-07-01

    The mitochondrial respiratory chain is organized within an array of supercomplexes that function to minimize the generation of reactive oxygen species (ROS) during electron transfer reactions. Structural models of supercomplexes are now known. Another recent advance is the discovery of non-OXPHOS complex proteins that appear to adhere to and seal the individual respiratory complexes to form stable assemblages that prevent electron leakage. This review highlights recent advances in our understanding of the structures of supercomplexes and the factors that mediate their stability.

  10. Evidence that grey seals (Halichoerus grypus use above-water vision to locate baited buoys

    Directory of Open Access Journals (Sweden)

    Arne Fjälling

    2007-01-01

    Full Text Available Fishing gear in the Baltic is often raided by grey seals (Halichoerus grypus. The seals remove the fish and damage the nets, or entangle themselves and drown. In order to develop ways of mitigating the seals-fisheries conflict, it is important to know exactly how the seals locate the fishing gear. A field experiment was conducted in order to clarify whether seals use their vision above water to do this. Bait (herring; Clupea harengus was attached to the anchor lines of buoys of the type that is commonly used to mark the position of fishing gear. In all, 643 buoys were set. Some of the buoys (210 were also fitted with camera traps. Weather data were collected from official weather stations nearby. Bait loss (mean 18% was significantly correlated with buoy size (P = 0.002 and wind speed (P = 0.04. There was a significant association between bait loss and seal observations near the buoys (P = 0.05. Five photos of grey seals were obtained from the camera traps. No fish-eating birds, such as cormorants or mergansers, were ever observed near the buoys or caught on camera. It was concluded that a main cause of missing bait was scavenging by grey seals, and that they did use above-water vision to locate the buoys. It was also concluded that wind strength (i.e. wave action contributed tothe bait loss. The camera trap buoys had a somewhat lower bait loss than the other buoys (P = 0.054, which was attributed to a scaring effect. Neither the number of seal observations nor the bait loss differed significantly between the 2 study areas in the experiment (P = 0.43 and P = 0.83, respectively. Bait loss was not affected by the buoy colour (red, white, or grey; P = 0.87. We suggest that the findings of this experiment could be put into practice in a seal-disturbed area by deploying a number of decoy buoys, or by hiding live buoys below the surface of the water. This would increase the cost of foraging for the seals, and hence discourage them from exploiting

  11. South Baltic wind atlas. South Baltic offshore wind energy regions project

    Energy Technology Data Exchange (ETDEWEB)

    Pena, A.; Hahmann, A.; Hasager, C.B.; Bingoel, F.; Karagali, I.; Badger, J.; Badger, M.; Clausen, Niels-Erik

    2011-05-15

    A first version of a wind atlas for the South Baltic Sea has been developed using the WRF mesoscale model and verified by data from tall Danish and German masts. Six different boundary-layer parametrization schemes were evaluated by comparing the WRF results to the observed wind profiles at the masts. The WRF modeling was done in a nested domain of high spatial resolution for 4 years. In addition the long-term wind statistics using the NCAR-NCEP reanalysis data were performed during 30 years to provide basis for a long-term adjustment of the results and the final WRF results include a weighting for the long-term trends variability in the South Baltic Sea. Observations from Earth observing satellites were used to evaluate the spatial resolution of the WRF model results near the surface. The QuikSCAT and the WRF results compared well whereas the Envisat ASAR mean wind map showed some variation to the others. The long-term analysis revealed that the South Baltic Sea has a spatially highly variable wind climate during the 30-years. (Author)

  12. Baltic companies prepare for stiff competition / Jorgen Johansson

    Index Scriptorium Estoniae

    Johansson, Jorgen

    2001-01-01

    "Baltic Sea Partenariat 2001" on Rootsi valitsuse toetatav projekt ärisidemete arendamiseks Rootsi ja Baltimaade ettevõtete vahel ning aitamaks läänemeremaade väikeettevõtetel valmistuda konkurentsiks EL-i turul

  13. IODP expedition 347: Baltic Sea basin paleoenvironment and biosphere

    DEFF Research Database (Denmark)

    Andrén, T; Jørgensen, Bo Barker; Cotterill, Carol

    2015-01-01

    The Integrated Ocean Drilling Program (IODP) expedition 347 cored sediments from different set- tings of the Baltic Sea covering the last glacial–interglacial cycle. The main aim was to study the geological development of the Baltic Sea in relation to the extreme climate variability of the region...... with changing ice cover and major shifts in temperature, salinity, and biological communities. Using the Greatship Manisha as a European Consortium for Ocean Research Drilling (ECORD) mission-specific platform, we recovered 1.6 km of core from nine sites of which four were additionally cored for microbiology......-rich clay. Due to the stratified water column of the brackish Baltic Sea and the recurrent and widespread anoxia, the deeper basins harbor laminated sediments that provide a unique opportunity for high-resolution chronological studies. The Baltic Sea is a eutrophic intra-continental sea that is strongly...

  14. Baltic Property Trust - professionaalseim kinnisvara investeerimisfirma Baltimere piirkonnas

    Index Scriptorium Estoniae

    2005-01-01

    BPT Eesti direktor Meelis Liivak Baltic Property Trusti (BPT) eesmärkidest, tegevusvaldkondadest ja tulevikuplaanidest. Kommenteerivad Alo Kullamaa, Priit Põldoja, Andres Järving ja Aivar Tomson. Lisa: Ajalugu

  15. Air Baltic: Estonian Air on nurka surutud / Teele Tammeorg

    Index Scriptorium Estoniae

    Tammeorg, Teele

    2010-01-01

    Air Balticu asepresidendi Janis Vanagsi hinnangul on Estonian Air aastaid jätnud tähelepanuta oma peamised turismiturud ning on praegu halvas seisus. Air Baltic on endiselt huvitatud Estonian Airi ostust. Majandus- ja kommunikatsiooniminister Juhan Partsi seisukoht

  16. Transborder corporate integration in the Baltic Sea Region

    Directory of Open Access Journals (Sweden)

    Kuznetsov Alexei

    2012-03-01

    Full Text Available The paper examines flows of foreign direct investment within the Baltic region. The author demonstrates close investment ties among the EU members, which are of special importance for Estonia, Latvia and Lithuania. Transborder corporate integration in the region is characterized by significant imbalances. In many aspects, it can be viewed as Sweden’s economic expansion or development of domestic markets for northern European companies. Although many German, Polish and Russian companies are involved in corporate integration in the Baltic region, other vectors of their foreign economic relations are still more important for them. As a result, the integration of Russian business in the Baltic part of the European integration area is still rather weak despite Russia’s considerable foreign direct investment in the Baltic States.

  17. Pan-Baltic airline talks again on the table

    Index Scriptorium Estoniae

    2009-01-01

    Baltimaad võivad luua ühise lennukompanii. Läti kommunikatsiooniministri Kaspars Gerhardsi, Leedu transpordiministri Eligijus Masiulise ja Eesti majandus- ja kommunikatsiooniministri Juhan Partsi arvamused. AirBaltic plaanib luua interneti-reisibürood

  18. Nitrogen fixation by cyanobacteria stimulates production in Baltic food webs.

    Science.gov (United States)

    Karlson, Agnes M L; Duberg, Jon; Motwani, Nisha H; Hogfors, Hedvig; Klawonn, Isabell; Ploug, Helle; Barthel Svedén, Jennie; Garbaras, Andrius; Sundelin, Brita; Hajdu, Susanna; Larsson, Ulf; Elmgren, Ragnar; Gorokhova, Elena

    2015-06-01

    Filamentous, nitrogen-fixing cyanobacteria form extensive summer blooms in the Baltic Sea. Their ability to fix dissolved N2 allows cyanobacteria to circumvent the general summer nitrogen limitation, while also generating a supply of novel bioavailable nitrogen for the food web. However, the fate of the nitrogen fixed by cyanobacteria remains unresolved, as does its importance for secondary production in the Baltic Sea. Here, we synthesize recent experimental and field studies providing strong empirical evidence that cyanobacterial nitrogen is efficiently assimilated and transferred in Baltic food webs via two major pathways: directly by grazing on fresh or decaying cyanobacteria and indirectly through the uptake by other phytoplankton and microbes of bioavailable nitrogen exuded from cyanobacterial cells. This information is an essential step toward guiding nutrient management to minimize noxious blooms without overly reducing secondary production, and ultimately most probably fish production in the Baltic Sea.

  19. Reactor cover system improvements. Final report FY 1978. [Seal, bearing, support, deck, vessel support

    Energy Technology Data Exchange (ETDEWEB)

    McEdwards, J.A.; Matteras, J.L.

    1978-01-01

    The effort in the reactor cover study area resulted in design recommendations for the vessel support, the deck, and the bearing and seals. Sixteen configurations of bearings and seals were examined as part of this study. The selected concepts use a double inflatable seal plus a sodium dip seal. Six different deck configurations were considered as part of this study. The most attractive of these concepts is the conical deck. Five different vessel support concepts were considered. Of these, the U ring appears to be the most attractive. Significant findings are the following: (1) verified that passive cooling of the deck and support lead to acceptable temperatures; (2) the assembly tolerances can be loosened for lower fabrication cost and easier operation while meeting positional and sealing requirements; (3) determined that the conical deck is the most effective deck configuration; (4) determined that the U ring is the most effective vessel support configuration; (5) selected a bearing and seal approach that gives effective gas sealing, adequate control of sodium frost, and easy maintenance.

  20. Analysing Sovereign Credit Default Swaps of Baltic Countries

    OpenAIRE

    Arvydas Kregzde; Gediminas Murauskas

    2015-01-01

    The paper analyses development of the Baltic sovereign CDS market. The level of commonalities and differences in credit risk of the Baltic countries with regard to CDS spreads is investigated. We apply principal component analysis, regression analysis, correlation analysis methods and Granger causality test. Driving forces for changes of CDS spreads in the individual country are established. We discover that the main impact of CDS spread changes arrives from external sources. Our study reveal...

  1. Review of western Baltic cod (Gadus morhua) recruitment dynamics

    DEFF Research Database (Denmark)

    Hüssy, Karin

    2011-01-01

    by the prevailing winds and currents. Drift is almost exclusively to the east, but the magnitude and its impact on the structure of the affected stocks (Kattegat, western Baltic, and eastern Baltic) remains unresolved. Salinity limits the east–west exchange of eggs as a consequence of the stocks' differential...... for spawning by both western and eastern stocks, the advection of early life stages from the west and immigration/emigration from the east....

  2. Baltic Climate Vulnerability Assessment Framework : Introduction and Guidelines

    OpenAIRE

    Hjerpe, Mattias; Wilk, Julie

    2010-01-01

    This Vulnerability Assessment Framework was put together within the project Baltic Challenges and Chances for local and regional development generated by Climate Change financed by the European Regional Development Fund and the Baltic Sea Region Programme 2007-2013. The purpose of the framework is to guide and assist the Target Areas (TA) within the project in mapping and analysing the challenges and chances created by climate change. The Vulnerability exercises have originally been developed...

  3. Nutrient trends through time in Sweden's Baltic Drainage Area

    Science.gov (United States)

    Fischer, I.; Destouni, G.; Prieto, C.

    2015-12-01

    Changes in climate and land-use have and will continue to modify regional hydrology, in turn impacting environmental health, agricultural productivity and water resource quality and availability. The Baltic region is an area of interest as the coast spans nine countries- serving over 100 million people. The Baltic Sea contains one of the largest human caused hypoxic dead zones due to eutrophication driven by anthropogenic excess loading of nutrients. Policies to reduce these loads include also international directives and agreements, such as the EU Water Framework Directive, adopted in 2000 to protect and improve water quality throughout the European Union, and the Baltic Sea Action Plan under the Helsinki Commission aimed specifically at reducing the nutrient loading to and mitigating the eutrophication of the Baltic Sea. In light of these policies and amidst the number of studies on the Baltic Sea we ask, using the accessible nutrient and discharge data what does nutrient loading look like today? Are the most excessive loads going down? Observed nutrient and flow time series across Sweden allow for answering these questions, by spatial and temporal trend analysis of loads from various parts of Sweden to the Baltic Sea. Analyzing these observed time series in conjunction with the ecological health status classifications of the EU Water Framework Directive, allows in particular for answering the question if the loads into the water bodies with the poorest water quality, and from those to the Baltic Sea, are improving, being maintained or deteriorating. Such insight is required to contribute to relevant and efficient water and nutrient load management. Furthermore, empirically calculating nutrient loads, rather than only modeling, reveals that the water body health classification may not reflect what water bodies actually contribute the heaviest loads to the Baltic Sea. This work also underscores the importance of comprehensive analysis of all available data from

  4. Face-Sealing Butterfly Valve

    Science.gov (United States)

    Tervo, John N.

    1992-01-01

    Valve plate made to translate as well as rotate. Valve opened and closed by turning shaft and lever. Interactions among lever, spring, valve plate, and face seal cause plate to undergo combination of translation and rotation so valve plate clears seal during parts of opening and closing motions.

  5. Seals. Grades 3-6.

    Science.gov (United States)

    New England Aquarium, Boston, MA.

    Explanations of a marine mammal rescue program and information on seals and sea lions are presented in this curriculum package for intermediate grade teachers. Activities are highlighted which focus on the natural history of harbor seals. This unit contains: (1) pre-trip activities (including fact sheets and worksheets on the different types of…

  6. Gulf and Dilmun Type seals

    DEFF Research Database (Denmark)

    Laursen, Steffen

    2011-01-01

    these Gulf Type‘ seals drew heavily on Indus Valley iconography and Indus script was occasionally employed in a pidgin-like manner. While the earliest circular seals incorporate features from Mesopotamian glyptic only to a lesser extent, this becomes a more important source of inspiration for later Dilmun...

  7. Forecasting Actions of Baltic elites: A Scenario Approach

    Directory of Open Access Journals (Sweden)

    Smirnov Vadim A.

    2016-09-01

    Full Text Available This paper provides an overview of different approaches to forecasting the future of the three Baltic States. The author’s theoretical approach to studying Baltic elites is used to forecast changes in the action models of the Baltic elites. The article stresses the scarcity of internal political processes in the Baltics. However, a significant number of scenarios focusing on military aspects in the Baltics have recently been published. The author distinguishes between inertia, confrontation, and cooperation scenarios and examines their prerequisites and possible consequences. The scenarios are developed based on an analysis of geographic, economic, and political factors. The decisive factor is a state-controlled foreign policy, which is affected by the international situation as well as relations between the state and the external resources exploited by political elites. The paper contributes to the general debate about the factors of political development and the role of political elites in it. The author pr ovides additional material for analysing possible developments in the domestic policies of the Baltic States in view of external factors.

  8. On Russian/Nordic Investment Competition in the Baltic States

    Directory of Open Access Journals (Sweden)

    Olenchenko Vladimir

    2015-06-01

    Full Text Available The researchers often overlook the relationships between Russian and Nordic investment capital; and even less attention is paid to studying the competition between the two. Yet this subject can be of particular relevance to the areas that are geographically, historically and culturally close to both Russia and the Nordic countries. Thus, the aim of this article is to understand how the competition between Russian and Nordic capital investment is played out in the Baltic States. The study discusses the principles of Russian and Nordic investment in the Baltic, and suggests ways to regulate these relations. To this end, we compare the investment conditions created in the Baltic States for both Russian and Nordic investors. The analysis shows that most of the Baltic market is controlled by the Nordic capital, which blocks the arrival of Russian investment to the Baltic States. With a nod to a number of previous studies, the authors of this article suggest some adjustments to the theory of foreign direct investment. The study will be also of practical interest to those Russian investors who are seeking entry points to the Baltic markets.

  9. Gas-path seal technology

    Science.gov (United States)

    Zuk, J.

    1976-01-01

    Improved gas-path seals are needed for better fuel economy, longer performance retention, and lower maintenance, particularly in advanced, high-performance gas turbine engines. Problems encountered in gas-path sealing are described, as well as new blade-tip sealing approaches for high-pressure compressors and turbines. These include a lubricant coating for conventional, porous-metal, rub-strip materials used in compressors. An improved hot-press metal alloy shows promise to increase the operating surface temperatures of high-pressure-turbine, blade-tip seals to 1450 K (2150 F). Three ceramic seal materials are also described that have the potential to allow much higher gas-path surface operating temperatures than are possible with metal systems.

  10. Aerodynamic seals for rotary machine

    Energy Technology Data Exchange (ETDEWEB)

    Bidkar, Rahul Anil; Cirri, Massimiliano; Thatte, Azam Mihir; Williams, John Robert

    2016-02-09

    An aerodynamic seal assembly for a rotary machine includes multiple sealing device segments disposed circumferentially intermediate to a stationary housing and a rotor. Each of the segments includes a shoe plate with a forward-shoe section and an aft-shoe section having multiple labyrinth teeth therebetween facing the rotor. The sealing device segment also includes multiple flexures connected to the shoe plate and to a top interface element, wherein the multiple flexures are configured to allow the high pressure fluid to occupy a forward cavity and the low pressure fluid to occupy an aft cavity. Further, the sealing device segments include a secondary seal attached to the top interface element at one first end and positioned about the flexures and the shoe plate at one second end.

  11. The Baltic Meetings 1957 to 1967

    CERN Document Server

    Høg, Erik

    2015-01-01

    The Baltic meetings of astronomers from Northern Germany and Scandinavia began in 1957 and gathered up to 70 participants. Reports of the presentations are available from all meetings, providing an overview of the interests of astronomers in this part of the world 50 years ago. Most interesting to see for a young astronomer in our days, I think, is that a large part of the time was about astrometry. This focus on astrometry was the basis for the scientific knowhow which made the idea of space astrometry realistic, resulting in the approval by ESA of the first astrometry satellite Hipparcos in 1980 which brought a revolution of high-precision astrometry of positions, motions and distances of stars. The correspondence with ten observatories shows that only one of them has any archive of letters at all from the 1950s, that is in Copenhagen where about 7000 letters on scientific and administrative matters are extant.

  12. Turbine and Structural Seals Team Facilities

    Data.gov (United States)

    Federal Laboratory Consortium — Seals Team Facilities conceive, develop, and test advanced turbine seal concepts to increase efficiency and durability of turbine engines. Current projects include...

  13. Resuspension patterns in the Baltic proper

    Science.gov (United States)

    Danielsson, Å.; Jönsson, A.; Rahm, L.

    2007-05-01

    Waves induce resuspension of surface sediments and contribute to the long-term mobilisation of particulate matter from erosion to accumulation bottoms. This has a major impact on the nutrient cycle in shallow seas by enhancing degradation, microbial production and recycling. The Baltic Sea represents such an area. The aim of this work is to analyse the spatial and temporal resuspension patterns in the Baltic Sea. To estimate the bottom friction velocity, modelled wave data are used in combination with data on grain size. This new data set is compared to a resuspension threshold of friction velocity to estimate the events of resuspension. The variation in bottom friction velocity, resuspension frequency and duration are related to wind climate, fetch, water depth and sediment type. Substantial resuspension can be found down to 40-60 m, with durations from one day to as much as two weeks. The highest winds in the area are highly anisotropic with a dominance of S-SW-W winds and the highest resuspension frequencies are found along the shallow eastern coasts. A seasonal pattern is observed with relatively high friction velocities and high resuspension frequencies during winter. There is also a variation depending on grain size, where sediments with fine and medium sand have a considerably higher percentage of resuspension events than bottoms with other dominant grain sizes. Five sub-areas are identified, characterised by different sediment types, resuspension and wind characteristics. If, in the future, wind speed increases as predicted, resuspension of sediments will also increase with effects on the nutrient cycle.

  14. Excitation by flows in seals and clearances. Part 1: Introduction: Fluid-structure-interactions in rotordynamics. Part 2: Identification of rotordynamic coefficients of annular seals

    Science.gov (United States)

    Nordmann, R.

    The fluid-structure interactions in rotor dynamics and the identification of rotor dynamic coefficients of annular seals are studied. The different fluid forces acting in the neck ring, the interstage seals, the balance pistons, the impellers and the oil film bearings of pumps are reviewed. These forces can have a large influence on the bending vibrations of a pump rotor. Theoretical and experimental models of fluid elements and of rotordynamics are presented. Simulations of the rotordynamic behavior show that the fluid forces of most elements can be described by linear-force relations. A theoretical model and an indentification procedure are presented to determine the dynamic coefficients of seals. The identified parameters confirm the assumptions in modeling and point out that the stiffness and damping characteristics of seals are significant for the stability behavior of pumps.

  15. Origami rings

    CERN Document Server

    Buhler, Joe; de Launey, Warwick; Graham, Ron

    2010-01-01

    Motivated by a question in origami, we consider sets of points in the complex plane constructed in the following way. Let $L_\\alpha(p)$ be the line in the complex plane through $p$ with angle $\\alpha$ (with respect to the real axis). Given a fixed collection $U$ of angles, let $\\RU$ be the points that can be obtained by starting with $0$ and $1$, and then recursively adding intersection points of the form $L_\\alpha(p) \\cap L_\\beta(q)$, where $p, q$ have been constructed already, and $\\alpha, \\beta$ are distinct angles in $U$. Our main result is that if $U$ is a group with at least three elements, then $\\RU$ is a subring of the complex plane, i.e., it is closed under complex addition and multiplication. This enables us to answer a specific question about origami folds: if $n \\ge 3$ and the allowable angles are the $n$ equally spaced angles $k\\pi/n$, $0 \\le k < n$, then $\\RU$ is the ring $\\Z[\\zeta_n]$ if $n$ is prime, and the ring $\\Z[1/n,\\zeta_{n}]$ if $n$ is not prime, where $\\zeta_n := \\exp(2\\pi i/n)$ is ...

  16. Metal pollutants and radionuclides in the Baltic Sea - an overview

    Directory of Open Access Journals (Sweden)

    Piotr Szefer

    2002-06-01

    Full Text Available This overview presents in detail the state of knowledge of the abilities of various components of the Baltic Sea environment to accumulate trace elements and radionuclides. Particular components of the Baltic ecosystem (abiotic and biotic are considered as potential monitors of pollutants. The use of seaweeds, e.g. Fucus vesiculosus or Zostera marina is recommended, also molluscs, e.g. Mytilus edulis, for biomonitoring surveys of metal pollutants and radionuclides in the Baltic Sea. However, several requirements need to be met if results are to be reliable. Since metal levels and radionuclide activities in the growing tips of F. vesiculosus reflect exclusively the levels of their dissolved species in the ambient seawater, this alga is very useful for monitoring dissolved species of metal pollutants and radioisotopes in the Baltic ecosystem. In contrast, M. edulis, a filter feeder is an appropriate tool for monitoring trace elements occurring in both chemical forms, i.e. dissolved and suspended species. Therefore, full information on the bioavailability and toxicity of heavy metals (depending on their chemical speciation as pollutants of the Baltic Sea can be obtained if at least two biomonitoring organisms are applied simultaneously, e.g. F. vesiculosus and M. edulis. Moreover, the data matrix can be interpreted more accurately if not only trace element but also macroelement concentrations (Ca, Mg, Na, K in these two representatives of Baltic phyto- and zoobenthos are taken into consideration; this point requires special attention. Two coastal species of fish, i.e. Zoarces viviparus and Perca fluviatilis, are good biomonitors of metallic contaminants, so their use as sentinels is recommended. The budgets of chemical elements and the ecological status of the Baltic Sea are presented. Several "black spots", e.g. large estuaries and seaport towns, heavily polluted by trace elements, are identified in the Baltic Sea and other enclosed seas such the

  17. Baltic Fibresi tekk katab Inglise kõrgklassi / Liis Kängsepp

    Index Scriptorium Estoniae

    Kängsepp, Liis, 1981-

    2005-01-01

    Tekke ja patju valmistav ettevõte OÜ Baltic Fibres tegutseb alles viiendat aastat, kuid on saavutanud edu teiste padjatootjate seas. Vt. samas: Padjatootjate kasumi sõi liitumine ELiga. Lisa: Baltic Fibres areneb tekstiilituru liidrist Wendrest kiiremini

  18. Kas Baltic Talks on oma missiooni täitnud? / Tiit Meren

    Index Scriptorium Estoniae

    Meren, Tiit

    2006-01-01

    21.-24. septembril toimus Tapal Läänemere-äärsete riikide reservohvitseride traditsiooniline suurfoorum Baltic Talks 2006. 1931. aastal Norra ja Rootsi reservohvitseride algatatud Nording Meeting ning Baltic Talks'i algus

  19. Friction Characteristics of Mechanical Seals with Laser-textured Seal Faces

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Heat generated by friction between faces of mechanica l seals is a major factor that causes deterioration of the seals and shortens th eir service life. Excessive temperature rise can greatly alter the seal geometry and vaporize the sealing fluid, resulting in friction of boundary lubrication. These effects on face seals usually lead to excessive leakage and ultimately ren der the seal inoperable. In order to maintain the reliability of seals, high fri ction and unwanted wear must be avoided. Using the l...

  20. 连续式混凝土搅拌机轴端密封的研究%Research on the Shaft Seal of Continuous Concrete Mixer

    Institute of Scientific and Technical Information of China (English)

    冯开林; 王少华; 李大伟

    2012-01-01

    When the continuous concrete mixer works,the concrete might seep into the shaft seal to increase the friction of the end face seal,and cause early sealing failure. The forces of the floating seal ring and the rotating hub of continuous concrete mixer were analyzed, and the optimum design of contact pressure of the end surface of floating seal ring from the O-ring and the average pressure of the sealing medium was carried out. The optimal values of contact pressure of the end surface and average pressure of the sealing medium were got, so the contact pressure of floating seal ring can maintain in the best range.%连续式混凝土搅拌机工作时混凝土可能渗入到轴端密封装置,加剧密封端面的摩擦,加速密封的失效.对连续式混凝土搅拌机浮动密封环和转毂进行力学分析,对浮动密封环受O型圈的接触压力和密封介质的平均压力进行优化设计,计算出其最优值,保证浮动密封环端面的接触压力保持在最佳区间.

  1. Sustainable manure management in the Baltic Sea Region - results, cases and project recommendations

    DEFF Research Database (Denmark)

    Tybirk, Knud; Luostarinen, S; Hamelin, Lorie;

    This magazine contains the major results, conclusions and recommendations of the project Baltic Forum for Innovative Technologies for Sustainable Manure Management (Baltic Manure) which via co-funding from Interreg Baltic Sea Region programme has been a Flagship project in the EU Strategy...... for the Baltic Sea Region from 2010-2013. The project has involved 18 partners from 8 countries with MTT Agrifood Research Finland as the Lead Partne...

  2. Fifth Baltic Sea pollution load compilation (PLC-5)

    Energy Technology Data Exchange (ETDEWEB)

    Knuuttila, S.; Svendsen, L.M.; Staaf, H.; Kotilainen, P.; Boutrup, S.; Pyhala, M.; Durkin, M.

    2011-07-01

    This report includes the main results from the Fifth Pollution Load Compilation abbreviated PLC-5. It includes quantified annual waterborne total loads (from rivers, unmonitored and coastal areas as well as direct point and diffuse sources discharging directly to the Baltic Sea) from 1994 to 2008 to provide a basis for evaluating any decreasing (or increasing) trends in the total waterborne inputs to the Baltic Sea. Chapter 1 contains the objectives of PLC and the framework on classification of inputs and sources. Chapter 2 includes a short description of the Baltic Sea catchment area, while the methods for quantification and analysis together with quality assurance topics are briefly introduced in Chapter 3. More detailed information on methodologies is presented in the PLC-5 guidelines (HELCOM 2006). Chapter 4 reports the total inputs to the Baltic Sea of nutrients and selected heavy metals. Furthermore, the results of the quatification of discharges and losses of nitrogen and phosphorus from point and diffuse sources into inland surface waters within the Baltic Sea catchment area (source-oriented approach or gross loads) as well as the total load to the maritime area (load-oriented approarch or net loads) in 2006 are shown. Typically, results are presented by country and by main Baltic Sea sub-region. In Chapter 5, flow normalization is introduced and the results of trend analyses on 1994-2008 time series data on total waterborne loads of nitrogen and phosphorus are given together with a first evaluation of progress in obtaining the provisional reduction targets by country and by main Baltic Sea sub-region. Chapter 6 includes discussion of some of the main conclusions and advice for future PLCs. The annexes contain the flow-normalized annual load data and figures and tables with results from the PLC-5.

  3. The Baltic Basin Case Study—towards a sustainable Baltic Europe

    Science.gov (United States)

    Jansson, Bengt-Owe; Stålvant, Carl-Einar

    2001-12-01

    Four watersheds, each characterized by a major resource use were selected for the study: The Vistula River in Poland—agriculture; the Dalälven River in Sweden—forestry; the Archipelago Sea in Sweden, Finland, Estonia—tourism; and the Lake Peipsi in Estonia/Russia—fisheries/agriculture. The main objective was to examine the reactions of particular ecosystems within the Baltic Sea drainage area, and to assess sustainability conditions on the regional level. The degree of sustainability and impact on the Baltic Sea were investigated through workshops and seminars in the areas. Overviews of environmental and socio-economic conditions were succinctly summarized in commissioned papers. Interventions by and discussions with scholars, sector experts, administrators and stakeholders of the various sites laid the foundation for conceptualizing the interaction of natural and human forces for each case. The project was able to draw quite a number of conclusions, summarized as the following lessons learnt. In the Vistula Region, nutrient emissions have levelled off but shortage of freshwater is critical. Forestry in the Dalälven watershed is largely environmental-friendly, except for fragmentation of the landscape and its negative impact on biodiversity. In the Archipelago area a former low-energy community has been replaced by a leisure time society. Different types of tourism is developing, but despite this variety, an improved integration of ecological properties with socio-economic patterns is required in order to build a sustainable, living Archipelago. The lake Peipsi basin and the surrounding area suffer both from problems of resource management and economic backwardness. Parts of the local economy has lost access to the one time large Soviet market, although the Estonian side has apparently benefited from present economic growth. To cope with the division of the lake, a regime for trans-national management is unfolding. It is based on both informal and, to an

  4. 7 CFR 29.35 - Lot seal.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Lot seal. 29.35 Section 29.35 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Regulations Definitions § 29.35 Lot seal. A seal approved by the Director for sealing lots...

  5. 7 CFR 29.34 - Sample seal.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Sample seal. 29.34 Section 29.34 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Regulations Definitions § 29.34 Sample seal. A seal approved by the Director for sealing...

  6. BALTEX - A science broker for the Baltic Sea Region

    Science.gov (United States)

    Reckermann, M.; von Storch, H.; Langner, J.; Omstedt, A. T.

    2010-12-01

    BALTEX (the Baltic Sea Experiment) is an interdisciplinary research network of scientists involved in environmental research dedicated to the Baltic Sea drainage basin (including disciplines such as meteorology, hydrology, oceanography, biogeochemistry and climate research). Originally founded in 1992 as a Continental Scale Experiment in GEWEX (the Global Energy and Water Cycle Experiment within the World Climate Research Programme (WCRP) of the World Meteorological Organization, WMO), it was intended to form a common science, communication and data platform with the overall goal to integrate efforts to gain a better understanding of the water and energy cycle in the Baltic Sea basin. BALTEX Phase II (since 2003) has extended the scope to research on regional climate change and variability, climate change impacts on biogeochemistry and water management, but also made first steps towards overarching social and political issues as cross-cutting activities in the context of the scientific objectives. An important aspect of BALTEX Phase II is a more holistic approach towards observing, understanding and modelling major environmental relevant for the entire Baltic Sea region. Parts of the BALTEX Phase II research activities thus contribute to the establishment of a high resolution integrated modelling system for Northern Europe, embedded in an Earth System Model. An outstanding product of BALTEX as a “knowledge broker” for regional political institutions is the BACC report. Following to a large extent the method of IPCC, a regional assessment report on climate change in the Baltic Sea basin was compiled, which summarizes the published scientifically legitimate knowledge on regional climate change in the Baltic Sea basin and its impacts. The assessment, known as the BACC report (BALTEX Assessment of Climate Change for the Baltic Sea Basin; BACC author team 2008, Reckermann et al., 2008) was published in 2008 as a book. A survey among climate researchers in the area

  7. Seal device for ferromagnetic containers

    Science.gov (United States)

    Meyer, Ross E.; Jason, Andrew J.

    1994-01-01

    A temporary seal or patch assembly prevents the escape of contents, e.g., fluids and the like, from within a container having a breach therethrough until the contents can be removed and/or a repair effected. A frame that supports a sealing bladder can be positioned over the breach and the frame is then attached to the container surface, which must be of a ferromagnet material, by using switchable permanent magnets. The permanent magnets are designed to have a first condition that is not attracted to the ferromagnetic surface and a second conditions whereby the magnets are attracted to the surface with sufficient force to support the seal assembly on the surface. Latching devices may be attached to the frame and engage the container surface with hardened pins to prevent the lateral movement of the seal assembly along the container surface from external forces such as fluid drag or gravity.

  8. Quantum String Seal Is Insecure

    CERN Document Server

    Chau, H F

    2006-01-01

    A quantum string seal encodes the value of a (bit) string as a quantum state in such a way that everyone can extract a non-negligible amount of information on the string by a suitable measurement. Moreover, such measurement must disturb the quantum state and is likely to be detected by an authorized verifier. In this way, the intactness of the encoded quantum state plays the role of a wax seal in the digital world. Here I analyze the security of quantum string seal by studying the information disturbance tradeoff of a measurement. This information disturbance tradeoff analysis extends the earlier results of Bechmann-Pasquinucci et al. and Chau by concluding that all quantum string seals are insecure. Specifically, I find a way to obtain non-trivial information on the string that escapes the verifier's detection with probability at least one half.

  9. Alaska Harbor Seal Glacial Surveys

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Floating glacial ice serves as a haul-out substrate for a significant number (10-15%) of Alaskan harbor seals, and thus surveying tidewater glacial fjords is an...

  10. Northern Fur Seal Food Habits

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains food habits samples, usually scats, collected opportunistically on northern fur seal rookeries and haulouts in Alaska from 1987 to present....

  11. Recipient Capacity of Tvaeren, a Baltic Bay

    Energy Technology Data Exchange (ETDEWEB)

    Agnedal, P.O.; Bergstroem, S.O.W.

    1966-07-15

    The research station at Studsvik is situated on the Baltic coast and includes several reactors and laboratories, a waste disposal plant serving both the station and waste producers outside Studsvik. A storage plant for irradiated fuel from power reactors has also been built. A total of 850 people are employed. The waste disposal plant was designed for a personnel of 900 using foreign information to correlate waste amounts to personnel. After a delay production has increased at a rate very close to the one expected. The composition of the waste is varied and difficult to predict. Minor amounts of fission products, active corrosion products, and fissile materials have been detected. Most of the waste activity is released to a strait leading into the Bay. Large volumes of water with very low specific activity are released immediately off the coast. Hydrological and dispersion data for the bay are quoted from a paper presented at the symposium mentioned below. The Baltic has brackish water. Both the chemistry and the biology are quite different from those of marine or fresh water recipients. A short description is given of the fauna and flora and important food webs are discussed. The different ways in which man is exposed to radioactivity in waste releases are dependent upon biological accumulation in living organisms and adsorption to dead materials. Fish consumption is the type of exposure which is likely to be the most critical, though it is possible that the exposure from sunbathing and fishing-gear handling could reach similar significance if conservative calculations are used. Accumulation factors from water to fish are given for iron, cobalt,and zinc . Permissible releases have been calculated using relevant accumulation factors. Fission products and corrosion products seem to be of similar significance with regard to possible human exposure. Permission to release liquid waste is granted by water courts in Sweden and operations inspected by special authorities

  12. Sedimentation rate in the Baltic Sea

    Energy Technology Data Exchange (ETDEWEB)

    Ilus, E.; Mattila, J.; Klemola, S.; Ikaeheimonen, T.K. [STUK Radiation and Nuclear Safety Authority (Finland); Niemisto, L. [Finnish Inst. of Marine Research (Finland)

    2001-04-01

    Varying redox conditions may affect the occurrence and concentrations of certain radionuclides in the surface layers of sediments and in near-bottom waters by causing remobilization of radionuclides from surface sediments to the overlying water and their settling back into the sediment. In recent decades about 70.000 km{sup 2} of the sea bottom in the deepest part of the Baltic Sea (about 19% of its total area) have withstood almost continuous anoxic conditions; thus, it is important to know to what extent depletion of oxygen can affect the behaviour of these radionuclides in near-bottom waters. The aim of the project was to resolve the above question in a coastal basin periodically undergoing anoxic conditions. Radioecological processes in sediments and in near-bottom water under varying redoxconditions were studied in the deep area of the Haestholmsfjaerden Bay in Loviisa (eastern Gulf of Finland) in 1995-1996. The Haestholmsfjaerden Bay is a semienclosed basin between the mainland and the archipelago and is connected with the open Gulf of Finland only through narrow, shallow sounds: In 1995, total depletion of oxygen occurred in the hypolimnion of Haestholmsfjaerden Bay during 2 periods in late summer and autumn. In 1996, oxygen conditions were the worst ever observed in the Haestholmsfjaerden deep. During early autumn anoxic conditions prevailed for more than 1 month in the near-bottom water. The highest total phosphorus and total nitrogen concentrations in the near-bottom water during these periods were 20- and 4- fold compared with the corresponding values in surface water. According to the results obtained in this project, remobilization of {sup 137}Cs and {sup 239,240}Pu from sediments to near-bottom water is negligible or non-existent in the Haestholmsfjaerden deep. If it does occur, however, it may be so slight that it is not possible to observe with the methods used in this study. Although the anoxic periods are quite short in the Haestholmsfjaerden deep

  13. Brush Seals for Improved Steam Turbine Performance

    Science.gov (United States)

    Turnquist, Norman; Chupp, Ray; Baily, Fred; Burnett, Mark; Rivas, Flor; Bowsher, Aaron; Crudgington, Peter

    2006-01-01

    GE Energy has retrofitted brush seals into more than 19 operating steam turbines. Brush seals offer superior leakage control compared to labyrinth seals, owing to their compliant nature and ability to maintain very tight clearances to the rotating shaft. Seal designs have been established for steam turbines ranging in size from 12 MW to over 1200 MW, including fossil, nuclear, combined-cycle and industrial applications. Steam turbines present unique design challenges that must be addressed to ensure that the potential performance benefits of brush seals are realized. Brush seals can have important effects on the overall turbine system that must be taken into account to assure reliable operation. Subscale rig tests are instrumental to understanding seal behavior under simulated steam-turbine operating conditions, prior to installing brush seals in the field. This presentation discusses the technical challenges of designing brush seals for steam turbines; subscale testing; performance benefits of brush seals; overall system effects; and field applications.

  14. Grease lubrication mechanisms in bearing seals

    OpenAIRE

    2011-01-01

    Rolling bearings contain seals to keep lubricant inside and contaminants outside the bearing system. These systems are often lubricated with grease; the grease acts as a lubricant for the bearing and seal and improves the sealing efficiency. In this thesis, the influence of lubricating grease on bearing seal performance is studied. Rheological properties of the grease, i.e. shear stress and normal stress difference, are evaluated and related to the lubricating and sealing performance of the s...

  15. Performance testing of elastomeric seal materials under low and high temperature conditions: Final report

    Energy Technology Data Exchange (ETDEWEB)

    BRONOWSKI,DAVID R.

    2000-06-01

    The US Department of Energy Offices of Defense Programs and Civilian Radioactive Waste Management jointly sponsored a program to evaluate elastomeric O-ring seal materials for radioactive material shipping containers. The report presents the results of low- and high-temperature tests conducted on 27 common elastomeric compounds.

  16. Response of the Baltic and North Seas to river runoff from the Baltic watershed - Physical and biological changes

    Science.gov (United States)

    Hänninen, Jari; Vuorinen, Ilppo; Rajasilta, Marjut; Reid, Philip C.

    2015-11-01

    Selected Baltic Sea watershed River Runoff (BSRR) events during 1970-2000 were used as predictor in Generalised Linear Mixed Models (GLIMMIX) for evidence of simultaneous changes/chain of events (including possible time lags) in some chemical, physical and biological variables in the Baltic and North Sea ecosystems. Our aim was to explore for climatic-based explanation for ecological regime shifts that were documented semi-simultaneously in both ecosystems. Certain similarities were identified in the North Sea and the Baltic Sea salinity, oxygen concentration, temperature and phyto- and zooplankton parameters. These findings suggest that BSRR events which originate in the Baltic Sea catchment area modify and contribute to large scale ecosystem changes not only in the Baltic Sea, but also in the adjacent parts of the North Sea. However, the Baltic Sea inter-annual and inter-decadal variabilities of physical and biological parameters are driven by direct atmospheric forcing, typically with a relatively short lag. In contrast, such changes in the North Sea are influenced by both local and direct atmospheric forcing, typically with a longer lag than in the Baltic, and a more regional, indirect forcing from changes in the North Atlantic. We suggest that this interactive system partially is behind large scale ecosystem regime shifts found in both Seas. During our study period two such shifts have been identified independently from us in a study earlier in the Southern and Central Baltic in 1980s and 1990s and a later one in 2001/2002 in the North Sea. As a post hoc test we compared the 0+ year class strength of the North Sea herring with BSRR intensity, and found evidence for higher herring production in high BSRR periods, which further corroborates the idea of a remote effect from the large watershed area of the Baltic. Regime shifts as well as their semi-synchronous appearance in two neighbouring sea areas could be identified. GLIMMIX models provide opportunities for

  17. An enigmatic spiny harvestman from Baltic amber

    Directory of Open Access Journals (Sweden)

    J. A. Dunlop

    2012-08-01

    Full Text Available A new harvestman (Arachnida: Opiliones from Baltic amber (Palaeogene: Eocene; ca. 44–49 Ma is described as Piankhi steineri n. gen., n. sp. This enigmatic fossil expresses long, slender pedipalps without a tarsal claw, which is characteristic for the suborder Dyspnoi. The chelicerae are notably enlarged and the dorsal body surface is formed from a carapace with a separate prosomatic tergite (metapeltidium, plus a large opisthosomal scute (or scutum parvum. However these characters, combined with the distinctly spiny limbs and further rows of spines across the fossil's opisthosoma, have no parallel among the modern dyspnoid harvestmen that we are aware of. The fossil resolves features reminiscent of modern members of the dyspnoid families Ceratolasmatidae, Nipponopsalididae, Ischyropsalididae and Sabaconidae, but does not show unequivocal apomorphies of any one particular family. We must entertain the possibility that this is an extinct body plan from the Eocene of north-central Europe, and we tentatively refer the fossil to a new genus in an unresolved position among the Ischyropsalidoidea (Dyspnoi. An amorphous triangular structure behind the anal region is assumed to be faecal matter, rather than part of the original anatomy. doi:10.1002/mmng.201200007

  18. Innovative economy in the Baltic Sea region

    Directory of Open Access Journals (Sweden)

    Mezhevich N. M.

    2012-01-01

    Full Text Available Innovative activity is carried out at three levels — those of the state, region and a company or a university. This article considers the level of development of knowledge-based economy in Germany, Denmark, Sweden, Finland, Estonia, Latvia, Lithuania, and Poland at each of the three levels, as well as descripes the spatial differentiation of innovative activity within the Baltic region. The analysis is done on the basis of national and international research, as well as statistical data on the intensity of research and development, structure of research expenditure, human capital in the field of advanced technologies, and the methods of institutional support for innovative activity. The authors characterise the role of business, university, and authorities — which constitute the «triple helix» — in national innovative systems. The article also analyses such important factors as the intensity of research and development, the share of employees in the field of advanced technologies, and the methods of public support. Examples of private-public infrastructure for the implementation of innovative projects are offered.

  19. Innovative economy in the Baltic Sea region

    Directory of Open Access Journals (Sweden)

    Mezhevich Nikolay

    2012-03-01

    Full Text Available Innovative activity is carried out at three levels — those of the state, region and a company or a university. This article considers the level of development of knowledge-based economy in Germany, Denmark, Sweden, Finland, Estonia, Latvia, Lithuania, and Poland at each of the three levels, as well as descripes the spatial differentiation of innovative activity within the Baltic region. The analysis is done on the basis of national and international research, as well as statistical data on the intensity of research and development, structure of research expenditure, human capital in the field of advanced technologies, and the methods of institutional support for innovative activity. The authors characterise the role of business, university, and authorities — which constitute the «triple helix» — in national innovative systems. The article also analyses such important factors as the intensity of research and development, the share of employees in the field of advanced technologies, and the methods of public support. Examples of private-public infrastructure for the implementation of innovative projects are offered.

  20. Russia’s energy geostrategy in the Baltic Sea region

    Directory of Open Access Journals (Sweden)

    Zeleneva Irina

    2013-06-01

    Full Text Available This article explores Russian energy policy in the Baltic Sea region in the context of the world energy market globalization. The study focuses on the three Baltic States — Latvia, Lithuania, and Estonia — which have a similar geographical location and history. The dynamic development of the region as a whole is strongly influenced by the stability of energy supply in each state. The article analyses the role Russia plays in the energy policy of the region from both geopolitical and geostrategic viewpoints. The author identifies the main characteristics of the Russian energy policy in these countries, and provides with a forecast for energy policy development in the region. A geostrategic approach dictates any successful energy policy in the Baltic Sea region to bring in line Russian interests with those of the European states.

  1. The transnational territorial transport system of the Baltic Region

    Directory of Open Access Journals (Sweden)

    Gumenyuk Ivan

    2012-03-01

    Full Text Available In this paper we focus on the structure and territorial borders of the Baltic Sea region, and examine the key structural elements of the transnational territorial transport system. In this respect, we clarify some terms used in transport geography. For the first time the transport system gets territorially localized, which allows for a broad range of new studies of transnational transportation in the Baltic Sea area. We also identify the main principles of development and operation of international territorial transport systems and present them taking the Baltic Sea region as an example. Our findings, we hope, will have a great practical application for researchers of transport geography, especially those studying international logistics.

  2. Projected habitat loss for Atlantic herring in the Baltic Sea.

    Science.gov (United States)

    Illing, Björn; Moyano, Marta; Hufnagl, Marc; Peck, Myron A

    2016-02-01

    Projected, climate-driven changes in rainfall patterns are expected to alter the salinity (S) of estuaries and larger brackish water bodies, such as the Baltic Sea. Some marine fish larvae are potentially more sensitive to low salinity than older stages, hence we compared the low salinity tolerance of Atlantic herring (Clupea harengus) larvae at the individual and population levels including four populations in the North and Baltic Seas. Acute low salinity tolerance was similar (S = 1.9-2.7) across populations and increased with increasing body size. Based on this physiological threshold and a regionally down-scaled climate model, spawning habitats in the northern and eastern Baltic Sea are projected to be largely unsuitable for herring by 2100. Although adaptive mechanisms may attenuate the effect in some species, the limited physiological tolerance of fish larvae will remain an important bottleneck for the persistence of marine fish populations in brackish waters undergoing climate-driven freshening.

  3. The concentrations of 241Pu in the southern Baltic Sea

    Directory of Open Access Journals (Sweden)

    Strumińska-Parulska D. I.

    2013-04-01

    Full Text Available The aim of the work was 241Pu activities determination in different components (water, plankton and fish of the southern Baltic Sea ecosystem. The determination of 241Pu in the samples was done indirectly by activity measuring the increment in 241Am from the decay of β-emitting 241Pu in samples collected 10-15 years after the Chernobyl accident. Enhanced levels of 241Pu were observed in all analyzed Baltic samples. The plutonium is also non-uniformly distributed between the organs and tissues of the analyzed fish; especially pelagic herring and cod as well as benthic flounder. The annual individual effective doses calculated on the basis of 241Pu concentrations in fish indicated that the impact of the consumption of 241Pu with Baltic fish on the annual effective dose for a statistical inhabitant of Poland was very small.

  4. Prime rings with PI rings of constants

    CERN Document Server

    Kharchenko, V K; Rodríguez-Romo, S

    1996-01-01

    It is shown that if the ring of constants of a restricted differential Lie algebra with a quasi-Frobenius inner part satisfies a polynomial identity (PI) then the original prime ring has a generalized polynomial identitiy (GPI). If additionally the ring of constants is semiprime then the original ring is PI. The case of a non-quasi-Frobenius inner part is also considered.

  5. Effects of Low Earth Orbit on Docking Seal Materials

    Science.gov (United States)

    Imka, Emily C.; Asmar, Olivia C.; deGroh, Henry C., III; Banks, Bruce A.

    2014-01-01

    Spacecraft docking seals are typically made of silicone elastomers. When such seals are exposed to low Earth orbit (LEO) conditions, they can suffer damage from ultraviolet (UV) radiation and atomic oxygen (AO, or monoatomic oxygen, the predominant oxygen species in LEO). An experiment flew on the International Space Station (ISS) to measure the effects of LEO on seal materials S0383-70 and ELA-SA-401 and various mating counterface materials which included anodized aluminum. Samples flown in different orientations received different amounts of UV and AO. The hypotheses were that most of the damage would be from UV, and 10 days or more of exposure in LEO would badly damage the seals. Eighteen seals were exposed for 543 days in ram (windward), zenith (away from Earth), or wake (leeward) orientations, and 15 control samples (not flown) provided undamaged baseline leakage. To determine post-flight leak rates, each of the 33 seals were placed in an O-ring groove of a leak test fixture and pressure tested over time. Resistance temperature detectors (RTDs), pressure transducers, and LabVIEW (National Instruments) programs were used to measure and analyze the temperature and pressure and calculate leakage. Average leakage of control samples was 2.6 x 10(exp -7) lbs/day. LEO exposure did not considerably damage ELA-SA-401. The S0383-70 flight samples leaked at least 10 times more than ELA-SA-401 in all cases except one, demonstrating that ELA-SA-401 may be a more suitable sealing material in LEO. AO caused greater damage than UV; samples in ram orientation (receiving an AO fluence of 4.3 x 10(exp 21) atoms/(sq cm) and in wake (2.9x 10(exp 20) atoms/(sq cm)) leaked more than those in zenith orientation (1.58 x 10(exp 20) atoms/(sq cm)), whereas variations in UV exposure did not seem to affect the samples. Exposure to LEO did less damage to the seals than hypothesized, and the data did not support the conjecture that UV causes more damage than AO.

  6. PRELIMINARY REPORT: EFFECTS OF IRRADIATION AND THERMAL EXPOSURE ON ELASTOMERIC SEALS FOR CASK TRANSPORTATION AND STORAGE

    Energy Technology Data Exchange (ETDEWEB)

    Verst, C.; Skidmore, E.; Daugherty, W.

    2014-05-30

    A testing and analysis approach to predict the sealing behavior of elastomeric seal materials in dry storage casks and evaluate their ability to maintain a seal under thermal and radiation exposure conditions of extended storage and beyond was developed, and initial tests have been conducted. The initial tests evaluate the aging response of EPDM elastomer O-ring seals. The thermal and radiation exposure conditions of the CASTOR® V/21 casks were selected for testing as this cask design is of interest due to its widespread use, and close proximity of the seals to the fuel compared to other cask designs leading to a relatively high temperature and dose under storage conditions. A novel test fixture was developed to enable compression stress relaxation measurements for the seal material at the thermal and radiation exposure conditions. A loss of compression stress of 90% is suggested as the threshold at which sealing ability of an elastomeric seal would be lost. Previous studies have shown this value to be conservative to actual leakage failure for most aging conditions. These initial results indicate that the seal would be expected to retain sealing ability throughout extended storage at the cask design conditions, though longer exposure times are needed to validate this assumption. The high constant dose rate used in the testing is not prototypic of the decreasingly low dose rate that would occur under extended storage. The primary degradation mechanism of oxidation of polymeric compounds is highly dependent on temperature and time of exposure, and with radiation expected to exacerbate the oxidation.

  7. Nitrogen surface water retention in the Baltic Sea drainage basin

    Directory of Open Access Journals (Sweden)

    P. Stålnacke

    2014-09-01

    Full Text Available In this paper, we estimate the surface water retention of nitrogen (N in all the 117 drainage basins to the Baltic Sea with the use of a statistical model (MESAW for source apportionment of riverine loads of pollutants. Our results show that the MESAW model was able to estimate the N load at the river mouth of 88 Baltic Sea rivers, for which we had observed data, with a sufficient degree of precision and accuracy. The estimated retention parameters were also statistically significant. Our results show that around 380 000 t of N are annually retained in surface waters draining to the Baltic Sea. The total annual riverine load from the 117 basins to the Baltic Sea was estimated to 570 000 t of N, giving a total surface water N retention of around 40%. In terms of absolute retention values, three major river basins account for 50% of the total retention in the 117 basins; i.e. around 104 000 t of N is retained in Neva, 55 000 t in Vistula and 32 000 t in Oder. The largest retention was found in river basins with a high percentage of lakes as indicated by a strong relationship between N retention (% and share of lake area in the river drainage areas. For example in Göta älv, we estimated a total N retention of 72%, whereof 67% of the retention occurred in the lakes of that drainage area (Lake Vänern primarily. The obtained results will hopefully enable the Helsinki Commission (HELCOM to refine the nutrient load targets in the Baltic Sea Action Plan (BSAP, as well as to better identify cost-efficient measures to reduce nutrient loadings to the Baltic Sea.

  8. Future conditions for integration of the Baltic Electricity Supply System

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-07-01

    The economies of Estonia, Latvia and Lithuania developed in close association with the north-west region of the former Soviet Union. This is especially true for energy supply systems and electricity generation and transmission; the Baltic States depend on Russia for much of their primary energy needs, and export power to Russia and Belarus. In restructuring their electricity industries, the Baltic States hope to establish closer relationships and trade with Western Europe. The initial focus has been on changes to the legislative framework, industry restructuring and the establishment of new regulatory institutions. Vertically integrated utilities are in the process of being broken up into a number of separate generation, transmission and distribution companies. This restructuring is a prelude to privatisation. The states aim to establish a common power market among themselves, and hope to integrate this market with neighbouring (Nordic and European) markets. Despite the target set by the Baltic authorities of a common market by 2001, there is little clarity, as yet, on the framework and guidelines for the structure and functioning of the market. This process is supported by other players in the region, and the EU has recently prioritised closer co-operation and harmonisation of power networks in the Baltic Sea region. The Swedish National Energy Administration has identified cooperation on energy and environmental issues in the Baltic Sea region as one of its priorities. Consequently, the Administration commissioned ECON to analyse the conditions for closer linkages between the Baltic and Nordic electricity systems. This report presents the findings of this analysis.

  9. Radical theory of rings

    CERN Document Server

    Gardner, JW

    2003-01-01

    Radical Theory of Rings distills the most noteworthy present-day theoretical topics, gives a unified account of the classical structure theorems for rings, and deepens understanding of key aspects of ring theory via ring and radical constructions. Assimilating radical theory's evolution in the decades since the last major work on rings and radicals was published, the authors deal with some distinctive features of the radical theory of nonassociative rings, associative rings with involution, and near-rings. Written in clear algebraic terms by globally acknowledged authorities, the presentation

  10. The forgotten type specimen of the grey seal [Halichoerus grypus (Fabricius, 1791)] from the island of Amager, Denmark

    DEFF Research Database (Denmark)

    Olsen, Morten Tange; Galatius, Anders; Biard, Vincent;

    2016-01-01

    assumptions; that there was no type specimen for the species and that the type locality lay in Greenland. Here, we describe a grey seal skull held in the collections of the Natural History Museum of Denmark, and present written and morphological evidence to demonstrate that this skull is identical...... and the island of Amager, Denmark, the type locality of the species. Hereby, the Baltic subspecies of the grey seal by definition becomes the nominate race of the species to henceforth be classified as Halichoerus grypus grypus, putting the hitherto used subspecies name macrorhynchus in reference to Hornschuch...... & Schilling (1850) in junior synonymy. As a further consequence, we resurrect Halichoerus grypus atlantica in reference to Nehring (1886) as the earliest available name for the Atlantic subspecies. The type specimen's digital, morphological and genetic data are made publicly available for future reference...

  11. Echoes from the past: a healthy Baltic Sea requires more effort.

    Science.gov (United States)

    Kotilainen, Aarno T; Arppe, Laura; Dobosz, Slawomir; Jansen, Eystein; Kabel, Karoline; Karhu, Juha; Kotilainen, Mia M; Kuijpers, Antoon; Lougheed, Bryan C; Meier, H E Markus; Moros, Matthias; Neumann, Thomas; Porsche, Christian; Poulsen, Niels; Rasmussen, Peter; Ribeiro, Sofia; Risebrobakken, Bjørg; Ryabchuk, Daria; Schimanke, Semjon; Snowball, Ian; Spiridonov, Mikhail; Virtasalo, Joonas J; Weckström, Kaarina; Witkowski, Andrzej; Zhamoida, Vladimir

    2014-02-01

    Integrated sediment multiproxy studies and modeling were used to reconstruct past changes in the Baltic Sea ecosystem. Results of natural changes over the past 6000 years in the Baltic Sea ecosystem suggest that forecasted climate warming might enhance environmental problems of the Baltic Sea. Integrated modeling and sediment proxy studies reveal increased sea surface temperatures and expanded seafloor anoxia (in deep basins) during earlier natural warm climate phases, such as the Medieval Climate Anomaly. Under future IPCC scenarios of global warming, there is likely no improvement of bottom water conditions in the Baltic Sea. Thus, the measures already designed to produce a healthier Baltic Sea are insufficient in the long term. The interactions between climate change and anthropogenic impacts on the Baltic Sea should be considered in management, implementation of policy strategies in the Baltic Sea environmental issues, and adaptation to future climate change.

  12. Implications of stock recovery for a neighbouring management unit: experience from the Baltic cod

    DEFF Research Database (Denmark)

    Eero, Margit; Hansen, Jakob Hemmer; Hüssy, Karin

    2014-01-01

    Cod in the Baltic Sea is assessed and managed as two separate stocks, i.e. eastern and western Baltic cod. The eastern Baltic cod has recently started to recover after several decades of severe depletion. In the present study, we suggest that the recovery of the eastern Baltic cod population has...... also substantially increased cod abundance in a specific area of the adjacent western Baltic management unit. This is investigated through long time-series of spatially resolved stock assessment data supplemented by genetic analyses of origin of the cod currently found in the transition area between...... the two populations. Due to immigrating cod from the east, there are currently large spatial differences in cod abundance and mean weight in the western Baltic management unit that raise new management concerns. First, the high abundance of cod of eastern origin found in the western Baltic management unit...

  13. Fish, fishing, and pollutant reduction in the Baltic Sea

    DEFF Research Database (Denmark)

    MacKenzie, Brian; Almesjö, L.; Hansson, S.

    2004-01-01

    The Baltic Sea is heavily polluted yet supports major Commercial fisheries for cod (Gadus morhua), herring (Clupea harengus), and sprat (Sprattus sprattus). Emissions of persistent organic pollutants, such as polychlorinated biphenyls (PCBs) and DDT, were high during the 1960s and 1970s, and conc......The Baltic Sea is heavily polluted yet supports major Commercial fisheries for cod (Gadus morhua), herring (Clupea harengus), and sprat (Sprattus sprattus). Emissions of persistent organic pollutants, such as polychlorinated biphenyls (PCBs) and DDT, were high during the 1960s and 1970s...

  14. Baltic Sea biodiversity status vs. cumulative human pressures

    DEFF Research Database (Denmark)

    Andersen, Jesper H.; Halpern, Benjamin S.; Korpinen, Samuli

    2015-01-01

    been developed to capture the consequences of multiple stressors for biodiversity, but the ability of these assessments to accurately predict biodiversity status has never been tested or ground-truthed. This relationship has similarly been assumed for the Baltic Sea, especially in areas with impaired...... status, but has also never been documented. Here we provide a first tentative indication that cumulative human impacts relate to ecosystem condition, i.e. biodiversity status, in the Baltic Sea. Thus, cumulative impact assessments offer a promising tool for informed marine spatial planning, designation...

  15. Baltic Nuclear workshop. Final report[Crisis communication

    Energy Technology Data Exchange (ETDEWEB)

    Wahlberg, L.G

    2001-05-01

    Proceedings of the NKS/BOK-1.6 workshop on crisis communication 'Baltic Nuclear', held in Stockholm March 19 -20, 2001, with participants from the nuclear power plants and nuclear authorities in the Baltic Sea region. The main content of the workshop was founded on the principle of 'learning by doing'. The participants were therefore practically trained in how to handle a crisis from an information and communication point of view. Added to that there were three different lectures. (au)

  16. Nitrogen fixation during an unusual summer Baltic Sea

    DEFF Research Database (Denmark)

    Voss, Maren; Dalsgaard, Tage; Fabian, Jenny

    Nitrogen fixation is a major nitrogen source for the open ocean. Also the land-locked, partly anoxic Baltic Sea receives almost as much nitrogen from nitrogen fixation as it receives from eutrophied rivers. Growth conditions for cyanobacteria are usually very favorable with low N/P ratios after...... winter mixing and a strong stratification and high surface temperatures in summer. However, the summer 2012 was quite different with strong winds and cold surface waters. Blooms of cyanobacteria therefore only developed in sheltered regions but not in the central Baltic Proper. Moreover, a greater...

  17. Controlling benthic release of phosphorus in different Baltic Sea scales

    DEFF Research Database (Denmark)

    Pitkänen, Heikki; Bendtsen, Jørgen; Hansen, Jørgen L. S.;

    to counteract anoxia and benthic release of nutrients in coastal marine conditions in the Baltic Sea. The project undertook monitoring of the pilot tests, modelling of effects at different scales, risk management, cost effectiveness and cost benefit analysis.......The general aim of the PROPPEN project was to study whether it is possible to counteract near-bottom anoxia and excess benthic nutrient release ("internal loading") in the Baltic Sea by artificial oxygenation in cost-efficient and socio-economically beneficial ways. Two pilot sites were selected...

  18. Causes of different impact of Major Baltic Inflows on cod reproduction in the Gotland Basin of the Baltic Sea

    Science.gov (United States)

    Karaseva, E. M.; Zezera, A. S.

    2016-09-01

    The impact of the Major Baltic Inflows (MBIs) of 1976, 1993, and 2003 on cod reproduction in the Gotland Basin of the Baltic Sea is considered based on calculations of the eastern Baltic cod egg abundance and offspring survival indices. The reproductive success (1976-1977) was defined by the elevation of the 11 psu isohaline and deepening of the 2 mL/L isooxygene surface, which provided the formation of a water layer suitable for cod spawning at a depth of 90-130 m. Prerequisites of the appearance of the reproductive layer in 1976-1977 were a previously high salinity level and penetrating two successive MBIs in one year. The cause of the weak MBI impact in 1993 was the previous salinity minimum; in 2003 it was rapid oxygen depletion due to an increase in temperature. As a result of their weaker influence, small and fragmented cod spawning biotopes appeared in the Gotland Basin.

  19. Harbour seals (Phoca vitulina and rehabilitation

    Directory of Open Access Journals (Sweden)

    Nynke Osinga

    2010-09-01

    Full Text Available Throughout the past few decades, rehabilitation of seals has become an activity that is anchored in the present day society of many countries. Seals are primarily rehabilitated to help individual animals in distress. At the same time, the release of seals which would have otherwise died can be considered as a contribution to the population. Most rehabilitated seals are animals under one year of age. They are mainly orphans, weaned seals with complications and seals with a parasiticbronchopneumonia. For the optimal handling of seals and their diseases, centralised operations with quality standards are essential. Rehabilitation provides an instrument to monitor the health of the seal population and its ecosystem. Changes in stranding trends or the appearance of new diseases can be monitored. Moreover, rehabilitation is important to show the general public thestate of the marine environment. In the Netherlands there is significant social support for the rehabilitation of seals. Experience obtained with seal care is of importance in countries where urgent help of threatened seal species is required. Here individual seals are also ambassadors to raise support for the protection of this species in general. Given that the anthropogenic impact on the seals and their environment is extensive in the Wadden Sea, rehabilitation centres can compensate the consequences of this impact on individual seals as well as the population as a whole.

  20. Sealing Performance of Labyrinth Seals against Small Oil Particles in HDDs

    Science.gov (United States)

    Miyatake, Masaaki; Yoshimoto, Shigeka; Dambara, Shinsuke; Nakamura, Taichi; Tanaka, Katsuhiko

    Small oil particles generated from lubricant for ball bearings in HDDs sometimes cause fatal problems such as head crashes. A labyrinth seal is often used to prevent oil particles from scattering onto the disk surfaces. In this paper, the sealing performance of labyrinth seals for small oil particles is investigated numerically and experimentally. Two types of labyrinth seal are considered, one a straight-type and the other a bent-type seal. It was found that the sealing capability of the labyrinth seal is generated by the centrifugal force exerted on oil particles due to disk rotation when they pass through the seal gap.

  1. Gas Path Sealing in Turbine Engines

    Science.gov (United States)

    Ludwig, L. P.

    1978-01-01

    A survey of gas path seals is presented with particular attention given to sealing clearance effects on engine component efficiency. The effects on compressor pressure ratio and stall margin are pointed out. Various case-rotor relative displacements, which affect gas path seal clearances, are identified. Forces produced by nonuniform sealing clearances and their effect on rotor stability are discussed qualitatively, and recent work on turbine-blade-tip sealing for high temperature is described. The need for active clearance control and for engine structural analysis is discussed. The functions of the internal-flow system and its seals are reviewed.

  2. Cryogenic Flange and Seal Evaluation

    Science.gov (United States)

    Ramirez, Adrian

    2014-01-01

    The assembly of flanges, seals, and pipes are used to carry cryogenic fluid from a storage tank to the vehicle at launch sites. However, after a certain amount of cycles these raised face flanges with glass-filled Teflon gaskets have been found to have torque relaxation and are as a result susceptible to cryogenic fluid leakage if not re-torqued. The intent of this project is to identify alternate combinations of flanges and seals which may improve thermal cycle performance and decrease re-torque requirements. The general approach is to design a test fixture to evaluate leak characteristics between spiral and concentric serrations and to test alternate flange and seal combinations. Due to insufficient time, it was not possible to evaluate these different types of combinations for the combination that improved thermal cycle performance the most. However, the necessary drawings for the test fixture were designed and assembled along with the collection of the necessary parts.

  3. Stirling engine piston ring

    Science.gov (United States)

    Howarth, Roy B.

    1983-01-01

    A piston ring design for a Stirling engine wherein the contact pressure between the piston and the cylinder is maintained at a uniform level, independent of engine conditions through a balancing of the pressure exerted upon the ring's surface and thereby allowing the contact pressure on the ring to be predetermined through the use of a preloaded expander ring.

  4. Birth Control Ring

    Science.gov (United States)

    ... Loss Surgery? A Week of Healthy Breakfasts Shyness Birth Control Ring KidsHealth > For Teens > Birth Control Ring A A A What's in this article? ... español Anillo vaginal anticonceptivo What Is It? The birth control ring is a soft, flexible, doughnut-shaped ring ...

  5. Actin Rings of Power.

    Science.gov (United States)

    Schwayer, Cornelia; Sikora, Mateusz; Slováková, Jana; Kardos, Roland; Heisenberg, Carl-Philipp

    2016-06-20

    Circular or ring-like actin structures play important roles in various developmental and physiological processes. Commonly, these rings are composed of actin filaments and myosin motors (actomyosin) that, upon activation, trigger ring constriction. Actomyosin ring constriction, in turn, has been implicated in key cellular processes ranging from cytokinesis to wound closure. Non-constricting actin ring-like structures also form at cell-cell contacts, where they exert a stabilizing function. Here, we review recent studies on the formation and function of actin ring-like structures in various morphogenetic processes, shedding light on how those different rings have been adapted to fulfill their specific roles.

  6. Alternative loop rings

    CERN Document Server

    Goodaire, EG; Polcino Milies, C

    1996-01-01

    For the past ten years, alternative loop rings have intrigued mathematicians from a wide cross-section of modern algebra. As a consequence, the theory of alternative loop rings has grown tremendously. One of the main developments is the complete characterization of loops which have an alternative but not associative, loop ring. Furthermore, there is a very close relationship between the algebraic structures of loop rings and of group rings over 2-groups. Another major topic of research is the study of the unit loop of the integral loop ring. Here the interaction between loop rings and group ri

  7. airBaltic claims monopoly abuse by RIX

    Index Scriptorium Estoniae

    2010-01-01

    AirBalticu andmetel on nende tasud peale 2009. aasta novembris Riia lennujaamas uute tasude süsteemi kehtestamist tõusnud, kuid Ryanairi tasud on langenud. AirBaltic plaanib nõuda Riia lennujaamalt kohtus 5,9 miljonit latti hüvitist

  8. Limits of fair play tested by airBaltic

    Index Scriptorium Estoniae

    2010-01-01

    AirBaltic reklaamikampaania käigus müüdi Eestis soodsaid lennupileteid erinevatesse sihtkohtadesse, kuid mõne aja möödudes tühistati osa ostetud lendudest. Hainan Airlines on valmis airBalticu osaluse ostma. Peaminister Valdis Dombrovskis on väidetavalt ka firma esindajatega Pekingis kohtunud, kuid eitab seda fakti

  9. Projekt "Baltenet - The Baltic Technology Network" / Leonid Pai

    Index Scriptorium Estoniae

    Pai, Leonid

    2005-01-01

    Baltenet - The Baltic Technology Network on projekt, mille alusel teevad koostööd tehniliste erialade koolituse arendamiseks Baltimere äärsetes riikides neli kutseõppeasutust Soomest, Rootsist, Lätis ja Eestist. Projekti rahastab Euroopa Liidu Leonardo da Vinci programm

  10. International Agreements in the Multispecies Baltic Sea Fisheries

    DEFF Research Database (Denmark)

    Nieminen, Emmi; Kronbak, Lone Grønbæk; Lindroos, Marko

    2016-01-01

    between the three countries can be stabilised when the most efficient country compensates the other countries. This solution is not feasible when using a single-species model for the cod population; thus, taking into account the multispecies nature of the Baltic Sea fisheries, the scope of cooperation...

  11. Early life migration patterns of Baltic Sea pike Esox lucius.

    Science.gov (United States)

    Rohtla, M; Vetemaa, M; Urtson, K; Soesoo, A

    2012-04-01

    This study investigated the movement patterns of Baltic Sea pike Esox lucius in Matsalu Bay, Estonia, using otolith microchemistry. Migration patterns of E. lucius were remarkably diverse, but distinct groups were evident. Of the E. lucius analysed (n = 28), 82% hatched in fresh water and 74% of them left this biotope during the first growth season.

  12. Public Risk Perceptions towards Oxygenation Pumping in the Baltic Sea

    DEFF Research Database (Denmark)

    Zandersen, Marianne

    This report provides the findings of national representative risk perception surveys undertaken in Finland, Lithuania and Sweden during 2011 in rela-tion to oxygenation pumping in the Baltic Sea. The risk perception surveys find that as the scale of pumping increases from small- to large scale...

  13. Baltic Metal - metallisektori koostööorgan / Endel Soon

    Index Scriptorium Estoniae

    Soon, Endel

    2004-01-01

    Ilmunud ka: EAKL Teataja : Narodnaja Gazeta, märts, nr. 3, 2004, lk. 4. Riias toimus Balti- ja Põhjamaade metalliala ametiühinguorganisatsioonide esindajate ühisnõupidamine. Kirjutati alla Baltimaade metallisektori koostööorgani Baltic Metal moodustamise leping

  14. Spatial and interannual variability in Baltic sprat batch fecundity

    DEFF Research Database (Denmark)

    Haslob, H.; Tomkiewicz, Jonna; Hinrichsen, H.H.;

    2011-01-01

    in the central Baltic Sea, namely the Bornholm Basin, Gdansk Deep and Southern Gotland Basin. Environmental parameters such as hydrography, fish condition and stock density were tested in order to investigate the observed variability in sprat fecundity. Absolute batch fecundity was found to be positively related...

  15. The electricity markets around the Baltic Sea; Elmarknaderna runt Oestersjoen

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-01

    A thorough description of the electric power markets in the countries surrounding the Baltic sea is given in this book. Environmental problems and regulations and nuclear power are surveyed. Factors that may affect an expanded trade of electricity between the countries are analyzed

  16. 16th Nordic-Baltic Conference on Biomedical Engineering

    CERN Document Server

    Persson, Mikael

    2015-01-01

    This volume presents the proceedings of the joint 16th Nordic-Baltic Conference on Biomedical Engineering & Medical Physics and Medicinteknikdagarna 2014!  The conference theme is Strategic Innovation. It aims at inspiring increased triple helix collaborations between health care providers, academia and the medtech industry.

  17. Invading Mnemiopsis leidyi as a potential threat to Baltic fish

    DEFF Research Database (Denmark)

    Haslob, H.; Clemmesen, C.; Schaber, M.;

    2007-01-01

    The occurrence of the ctenophore Mnemiopsis leidyi as a new invasive species in the Baltic Sea and the potential consequences for fish stock recruitment was investigated in spring 2007. The study focused on the Bornholm Basin, which serves as the major spawning ground for cod and sprat, the comme...

  18. Past Occurrences of Hypoxia in the Baltic Sea

    Science.gov (United States)

    Zillen, L.; Conley, D. J.; Bjorck, S.

    2007-12-01

    The hypoxic zone in the Baltic Sea has increased in area by about four times since 1950. Widespread oxygen deficiency below the halocline has severely reduced macro benthic communities in the Baltic Proper and the Gulf of Finland over the past decades and negatively effected food chain dynamics, fish habitats and fisheries in the entire Baltic Sea. In addition, hypoxia alters nutrient biogeochemical cycles. The cause of the increased hypoxia is believed to be enhanced eutrophication through increased anthropogenic input of nutrients, such as phosphorous and nitrogen. Conditions prior to the 1950s are considered as the benchmark and some authors suggest that the earlier Baltic Sea was an oligothrophic, clear-water body with oxygenated deep waters. By contrast, studies of short sediment cores reveal that hypoxia has been present in some of the deepest basins for at least the last 100-200 years. In addition, long sediment cores suggest that hypoxia in the Baltic Sea has occurred intermittently in deep basins over the last c. 8500 years. Thus, the occurrence of present day hypoxia in the deeper basins need not necessarily be attributed to human activity but rather to natural oceanographic, geologic and climate conditions. We present a compilation of previous publications that reported the occurrence of laminated sediments (i.e. a palaeo-proxy for hypoxia) in the Baltic Sea. This review shows that the deeper parts of the Baltic Sea have experienced either intermittent or more regular hypoxia during most of the Holocene and that more continuous laminations started to form c. 7800-8500 cal. yr BP ago, in association with the establishment of a permanent halocline during the transition from the Ancylus Lake to the Littorina Sea. Laminated sediments were more common during the early and late Holocene and coincided with intervals of high organic productivity (high TOC content) and high salinity during the Holocene Thermal Maximum and the Medieval Climate Optimum. This study

  19. Legacy HMSRP Hawaiian Monk Seals Observers

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set documents observers that have collected monk seal data as part of the ongoing monk seal population assessment efforts by PSD personnel and cooperating...

  20. HMSRP Hawaiian Monk Seal Handling Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains records for all handling and measurement of Hawaiian monk seals since 1981. Live seals are handled and measured during a variety of events...

  1. HMSRP Hawaiian Monk Seal Entanglement data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data set contains records of all entanglements of Hawaiian monk seals in marine debris. The data set comprises records of seals entangled by derelict fishing...

  2. Film riding seals for rotary machines

    Energy Technology Data Exchange (ETDEWEB)

    Bidkar, Rahul Anil; Sarawate, Neelesh Nandkumar; Wolfe, Christopher Edward; Ruggiero, Eric John; Raj Mohan, Vivek Raja

    2017-03-07

    A seal assembly for a rotary machine is provided. The seal assembly includes multiple sealing device segments disposed circumferentially intermediate to a stationary housing and a rotor. Each of the segments includes a shoe plate with a forward-shoe section and an aft-shoe section having one or more labyrinth teeth therebetween facing the rotor. The sealing device includes a stator interface element having a groove or slot for allowing disposal of a spline seal for preventing segment leakages. The sealing device segment also includes multiple bellow springs or flexures connected to the shoe plate and to the stator interface element. Further, the sealing device segments include a secondary seal integrated with the stator interface element at one end and positioned about the multiple bellow springs or flexures and the shoe plate at the other end.

  3. Legacy HMSRP Hawaiian Monk Seal Ultrasound Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Ultrasounds measuring the condition of juvenile seals at Laysan Island during 2009-2010, collected when seals were handled as part of the De-Worming Project

  4. Measurements of apex seal behavior in a rotary engine using four displacement sensors; Rotary engine no apex seal kyodo. Yon`i sensor ni yoru sokutei

    Energy Technology Data Exchange (ETDEWEB)

    Matsuura, K. [Aoyama Gakuin University, Tokyo (Japan). College of Science and Engineering

    1997-05-25

    Behavior measurements of an apex seal of three-piece slanted horizontal split type were made, using an overhanging eccentric shaft-type single-rotor engine equipped with a multichannel packaged slip ring. To analyze the behavior, a computer plotting program was developed, by means of which the sequences of the configuration of top and bottom parts in the slot at given eccentric shaft angles were plotted on the trochoidal curves from the measured displacement data. The measurement results revealed the details of the behavior. Under high working chamber pressure, the top part of the leading apex seal is flush with the leading side of the slot, while that of the trailing apex seal is considerably tilted with respect to the trailing edge of the slot. 8 refs., 15 figs., 1 tab.

  5. Postglacial paleoceanographic environments in the Barents and Baltic seas

    Science.gov (United States)

    Ivanova, E. V.; Murdmaa, I. O.; Emelyanov, E. M.; Seitkalieva, E. A.; Radionova, E. P.; Alekhina, G. N.; Sloistov, S. M.

    2016-01-01

    This paper presents reconstructions of ice sheet boundaries, lacustrine and marine paleobasins, as well as the connections of the Barents and Baltic seas with the North Atlantic from the Last Glacial Maximum to the Holocene. The reconstructions are based on original and published data obtained from the northern and western parts of the Barents Sea and Baltic depressions with account for the available regional schematic maps of deglaciation. The early deglaciation of the Scandinavian-Barents ice sheet culminated with the Bølling-Allerød interstadial (14.5-12.9 cal ka BP), which was characterized by a more vigorous Atlantic meridional overturning circulation (AMOC) and a corresponding increase in surface Atlantic water inflow into the Barents Sea through deep troughs. The Baltic Ice Lake (BIL) remained a dammed-up isolated basin during deglaciation from 16.0 to 11.7 cal ka BP. In the Younger Dryas (YD), the lake drained into the North Sea and was replaced by a brackish Yoldia Sea (YS) at the beginning of the Holocene (Preboreal, 11.7-10.7 cal ka BP), due to a limited connection between two basins through the Närke Strait. In the Barents Sea, the next increase in the Atlantic water influx into the deep basins corresponded to terminal YD and Preboreal events with a culmination in the Early Holocene. The Yoldia Sea became a lake again during the next stage, the Ancylus (~10.7-8.8 cal ka BP). Atlantic water inflow both into the Barents and Baltic seas varied during the Holocene, with a maximum contribution in the Early Holocene, when the Littorina Sea (LS, 8-4 cal ka BP) connection with the North Sea via the Danish Straits was formed to replace the Ancylus Lake. The recent, post-Littorina stage (PS, the last 4 cal ka) of the Baltic Sea evolution began in the Late Holocene.

  6. An international scope of the regional journal Baltic Astronomy

    Science.gov (United States)

    Bartasiute, Stanislava

    2015-08-01

    The internationalization of publishing has been progressing in most fields of science, including astronomy and physics in particular. Along with high quality journals having a completely international readership, national and regional journals represent a significant part in number, whereas their average impact is very diverse and not always competitive. Based mainly on the Web of Science data, we will give a comparative analysis of astronomy journals published in/for countries with relatively small astronomical communities, such as Baltic and some Eastern European. Bibliometric statistics will be presented of one of such journals, Baltic Astronomy, established in 1992 as a result of cooperation between astronomers of Latvia, Lithuania, and Estonia. Since the first years of publishing this journal has been evolving from regional to the more internationalized status. The list of countries of contributing authors has expanded to 54, while only 19% of the articles are from the three Baltic countries, mainly from Lithuania (14%) and, to a much lesser extent, from Estonia (3%) and Latvia (2%). Recognizing the inadequacies of national and regional bases for dissemination and exchange of scientific information, the Baltic astronomical communities themselves move, however, towards internationalization: in international journals Latvia publishes twice and Estonia nearly ten times more articles than they do in Baltic Astronomy. Meanwhile Lithuanian astronomers publish nearly the same number of articles both outside and inside the region. In the light of progress being made toward consolidation of scholarly publications, a choice between a national/regional and international basis for publishing is becoming more decisive for the future of national and regional astronomy journals.

  7. Multi-layer seal for electrochemical devices

    Science.gov (United States)

    Chou, Yeong-Shyung [Richland, WA; Meinhardt, Kerry D [Kennewick, WA; Stevenson, Jeffry W [Richland, WA

    2010-09-14

    Multi-layer seals are provided that find advantageous use for reducing leakage of gases between adjacent components of electrochemical devices. Multi-layer seals of the invention include a gasket body defining first and second opposing surfaces and a compliant interlayer positioned adjacent each of the first and second surfaces. Also provided are methods for making and using the multi-layer seals, and electrochemical devices including said seals.

  8. Multi-layer seal for electrochemical devices

    Science.gov (United States)

    Chou, Yeong-Shyung [Richland, WA; Meinhardt, Kerry D [Kennewick, WA; Stevenson, Jeffry W [Richland, WA

    2010-11-16

    Multi-layer seals are provided that find advantageous use for reducing leakage of gases between adjacent components of electrochemical devices. Multi-layer seals of the invention include a gasket body defining first and second opposing surfaces and a compliant interlayer positioned adjacent each of the first and second surfaces. Also provided are methods for making and using the multi-layer seals, and electrochemical devices including said seals.

  9. [Baltic connections : archival guide to the maritime relations of the countries around the Baltic Sea (including the Netherlands) 1450-1800)] / Enn Küng

    Index Scriptorium Estoniae

    Küng, Enn

    2009-01-01

    Arvustus: Baltic connections : archival guide to the maritime relations of the countries around the Baltic Sea (including the Netherlands) 1450-1800). Leiden, Boston : Brill, 2007. Lisaks raamatule on arhiivijuht kättesaadav ka elektrooniliselt http://www.balticconnections.net/

  10. Predicting Leakage in Labyrinth Seals

    Science.gov (United States)

    Morrison, G. L.; Rhode, D. L.; Cogan, K. C.; Chi, D.; Demko, J.

    1985-01-01

    Analytical and empirical methods evaluated. 264-page report presents comprehensive information on leakage in labyrinth seals. Summarizes previous analyses of leakage, reviews leakage tests conducted by authors and evaluates various analytical and experimental methods of determining leakage and discusses leakage prediction techniques.

  11. Pre-sealing risk analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ensminger, D.A.; Hough, M.E.; Oston, S.G.

    1980-01-07

    This report describes studies of accidents involving high-level radioactive waste before sealing the waste into a repository. The report summarizes work done in this area during Fiscal Year 1978 and supplements previous work. Models of accident probability, severity, and consequences are refined and extended.

  12. Internal stress distribution of X-ring using photoelastic experimental hybrid method

    Energy Technology Data Exchange (ETDEWEB)

    Bernard, Alunda Ouma [Dedan Kimathi University of Technology, Nyeri (Kenya); Hawong, Jai Sug; Lim, Hyun Seok [Yeungnam University, Gyeongsan (Korea, Republic of); Shin, Dong Chul [Koje College, Geoje (Korea, Republic of)

    2014-05-15

    Sealing elements are essential parts of many machines, and are used to prevent the loss of a fluid or gas. When such fluids are not properly sealed, catastrophic failures may result. Many different types of rings have been developed to suit various industrial needs. Considerable research has been done on the O-ring. We analyze the internal stresses developed in an X-ring under a uniform squeeze rate of 20%, which is suitable for static applications, using a photoelastic experimental hybrid method. The internal pressures applied were 0.98, 1.96, 2.94, 3.92, 4.90, and 5.88 MPa. We show that sealing rings with X geometry have considerably higher internal stresses than O-ring seals. In addition, we demonstrate that after extrusion, for an internal pressure of 5.88 MPa, the two lobes on the upper contact surface merge, thereby increasing the contact length of the upper side significantly. Extrusion in the X-ring occurred when the internal pressure was 4.90 MPa.

  13. Aerodynamic seal assemblies for turbo-machinery

    Energy Technology Data Exchange (ETDEWEB)

    Bidkar, Rahul Anil; Wolfe, Christopher; Fang, Biao

    2015-09-29

    The present application provides an aerodynamic seal assembly for use with a turbo-machine. The aerodynamic seal assembly may include a number of springs, a shoe connected to the springs, and a secondary seal positioned about the springs and the shoe.

  14. Piston rod seal for a Stirling engine

    Science.gov (United States)

    Shapiro, Wilbur

    1984-01-01

    In a piston rod seal for a Stirling engine, a hydrostatic bearing and differential pressure regulating valve are utilized to provide for a low pressure differential across a rubbing seal between the hydrogen and oil so as to reduce wear on the seal.

  15. Ergonomics and safety of manual bag sealing.

    NARCIS (Netherlands)

    Groot, M.D. de; Bosch, T.; Eikhout, S.M.; Vink, P.

    2005-01-01

    A variety of seals is used to close bags. Each seal has advantages and disadvantages. For shop assistants sealing bags could be a repetitive physically demanding action. Opening and closing the bags again can cause some discomfort or annoyance for consumers. Besides, it is an activity which can enda

  16. Annular Pressure Seals and Hydrostatic Bearings

    Science.gov (United States)

    2006-11-01

    affecting the rotordynamics of liquid turbopumps, in particular those handling large density fluids. Highlights on the bulk-flow analysis of annular seals... rotordynamic stability. Hydrostatic bearings rely on external fluid pressurization to generate load support and large centering stiffnesses, even in...SEALS IN PUMP APPLICATIONS Seal rotordynamic characteristic have a primary influence on the stability response of high-performance turbomachinery [1

  17. Characteristics of a magnetic fluid seal and its motion in an axial variable seal gap

    Institute of Scientific and Technical Information of China (English)

    QIAN Ji-guo; YANG Zhi-yi

    2008-01-01

    With suitable assumptions a hydrodynamic model for the magnetic fluid motion in an axial variable gap seal was constructed, and the solution to the equations of the model was deduced. The characteristics of a magnetic fluid seal and its motion,including the speed and pressure distribution, and the seal capacity of a magnetic fluid rotating seal were systematically described.The factors affecting seal capacity and ways to improve seal capacity based on the hydrodynamic model are discussed. The basic condition for dynamic seal availability is presented. The rotating speed and radius of the shafts should be decreased. The work can provide proof of a seal design or suggest ways to improve the seal capacity of magnetic fluid seals.

  18. On JB-Rings

    Institute of Scientific and Technical Information of China (English)

    Huanyin CHEN

    2007-01-01

    A ring R is a QB-ring provided that aR + bR = R with a, b ∈ R implies that there exists a y ∈ R such that a+by ∈ R-1q. It is said that a ring R is a JB-ring provided that R/J(R) is a QB-ring, where J(R) is the Jacobson radical of R. In this paper, various necessary and sufficient conditions, under which a ring is a JB-ring, are established. It is proved that JB-rings can be characterized by pseudo-similarity. Furthermore, the author proves that R is a J B-ring iff so is R/J(R)2.

  19. Do countries catch cold when trading partners sneeze? Evidence from spillovers in the Baltics

    Directory of Open Access Journals (Sweden)

    Kingsley I. Obiora

    2010-06-01

    Full Text Available How do countries respond to shocks from their major trading partners? This paper addresses the question in the context of the observed shifts in trade linkages between the Baltic countries and their major trading partners. Vector autoregression (VAR models were used to examine the magnitude and sources of growth spillovers to the Baltics from key trading partners, as well as shocks from the real effective exchange rate (REER.Our results show there are significant cross-country spillovers to the Baltics, with spillovers from the EU outweighing those from Russia. Shocks to the REER generally depress growth in the Baltics, and this effect rises over time. We also find that financial and trade linkages are the dominant transmission channels of spillovers to the region, which explains the current realization of downside risks to the Baltics from the global slowdown. In general, therefore, these results suggest that the Baltics are susceptible to shocks from their key trading partners.

  20. Assessing cumulative pressures and impacts in a regional scale: HELCOM Baltic Sea Impact Index

    DEFF Research Database (Denmark)

    Korpinen, S.; Meski, L.; Andersen, Jesper;

    of identifying hot spots needs to be replaced by spatial high-resolution maps associated with estimated impacts on key ecosystem components. The Baltic Sea Marine Environment Protection Commission (HELCOM) took a first step towards an initial regional assessment of anthropogenic pressures in the Initial Holistic...... of macrozoobenthic communities in some Baltic sub-basins and the results have suggested that more specific selection of pressures is needed in order to assess anthropogenic impacts on benthic habitats. Such an adaptation of the tool has already been tested to assess the sea-floor integrity under the MSFD qualitative...... Assessment of the Baltic Sea by producing the Baltic Sea Pressure Index (BSPI) and the Baltic Sea Impact Index (BSII). The BSPI visualizes cumulative anthropogenic pressures in the Baltic Sea scale, whereas the BSII consists of potential impacts of anthropogenic pressures on key ecosystem components...

  1. On semi ring bornologies

    Science.gov (United States)

    Imran, A. N.; Rakhimov, I. S.; Husain, Sh. K. Said

    2016-06-01

    Our main focus in this work is to introduce new structure bornological semi rings. This generalizes the theory of algebraic semi rings from the algebraic setting to the framework of bornological sets. We give basic properties for this new structure. As well as, We study the fundamental construction of bornological semi ring as product, inductive limits and projective limits and their extensions on bornological semi ring. Additionally, we introduce the category of bornological semi rings and study product and pullback (fiber product) in the category of bornological semi rings.

  2. Mechanism and Performance Analysis of Annular Metal Seal Assembly%环形金属密封总成密封机制及性能分析

    Institute of Scientific and Technical Information of China (English)

    侯超; 秦浩智; 肖文生; 刘健

    2014-01-01

    Annular metal seal assembly is an important part of the subsea wellhead system,its quality directly affects the security of subsea wellhead system,and even the reliability of subsea oil and gas system.By discussing the mechanism and working principle of annular metal seal assembly,the sealing performances were analyzed from the deformation of sealing ring in the sealing process and combining with the finite element analysis results.The results show that the seal can be a-chieved at the elastic deformation stage of sealing ring,but there is high demand of surface roughness and quality that the annular seal assembly cannot be guarantee under the working conditions.The sealing ring can achieve good seal because the surface defects of the sealing ring can be filled at the stage of plastic deformation.The deflection of the sealing ring contact surface becomes the only factor affecting sealing performance at plastic deformation stage.%环形金属密封总成是水下井口头系统重要组成部分,其性能直接影响到水下井口头系统的安全性,甚至整个水下油气系统的可靠性。分析环形金属密封总成的密封机制和工作原理,结合有限元分析结果,从密封环在密封过程中的变形情况来分析其密封性能。结果表明:密封环在弹性变形阶段可以实现密封,但对密封环的表面粗糙度和表面质量有很高的要求,在环形密封总成工况条件下无法保证,应避免在此阶段实现密封;密封环在塑性变形阶段能够填补环表面存在的缺陷,实现良好的密封;在塑性变形阶段,密封环接触面的变形情况成为影响密封性能的唯一因素。

  3. Self-Sealing Wet Chemistry Cell for Field Analysis

    Science.gov (United States)

    Beegle, Luther W.; Soto, Juancarlos; Lasnik, James; Roark, Shane

    2012-01-01

    In most analytical investigations, there is a need to process complex field samples for the unique detection of analytes, especially when detecting low concentration organic molecules that may identify extraterrestrial life. Wet chemistry based instruments are the techniques of choice for most laboratory- based analysis of organic molecules due to several factors including less fragmentation of fragile biomarkers, and ability to concentrate target species resulting in much lower limits of detection. Development of an automated wet chemistry preparation system that can operate autonomously on Earth and is also designed to operate under Martian ambient conditions will demonstrate the technical feasibility of including wet chemistry on future missions. An Automated Sample Processing System (ASPS) has recently been developed that receives fines, extracts organics through solvent extraction, processes the extract by removing non-organic soluble species, and delivers sample to multiple instruments for analysis (including for non-organic soluble species). The key to this system is a sample cell that can autonomously function under field conditions. As a result, a self-sealing sample cell was developed that can autonomously hermetically seal fines and powder into a container, regardless of orientation of the apparatus. The cap is designed with a beveled edge, which allows the cap to be self-righted as the capping motor engages. Each cap consists of a C-clip lock ring below a crucible O-ring that is placed into a groove cut into the sample cap.

  4. Symmetries in Images on Ancient Seals

    CERN Document Server

    Sparavigna, Amelia

    2008-01-01

    In this paper, we discuss the presence of symmetries in images engraved on ancient seals, in particular on stamp seals. Mainly used to secure the containers from tampering and for owner's identification, these objects appeared during the 5th millennium BC in Mesopotamia. Usually the seals were engraved with simple images, suitable to communicate an immediate information. Rotational symmetries are already displayed by the most ancient stamp seals, whose images reach a quasi-perfect symmetry in their small circular or ovoid spaces. Bilateral symmetries are quite common in Egyptian scarab seals.

  5. Reinventing the Baltic Sea Region: From the Hansa to the Eu-Strategy of 2009

    Directory of Open Access Journals (Sweden)

    Michael North

    2012-11-01

    Full Text Available The political changes of 1989 stimulated a new perception and perspective of the Baltic Sea Region. And this gained momentum with the Eastern Enlargement of the EU. The new situation encouraged research as well. In this context the “Baltic Sea” is not an unchangeable physical setting, but also a construction of different actors or protagonists. People and powers continuously reinvent the Baltic Sea Region. That is why; the following paper focuses on the different notions of the Baltic Sea Region from the Middle Ages up to now and also examines the recent EU-Strategy of this region.

  6. The diet of whiting Merlangius merlangus in the western Baltic Sea

    DEFF Research Database (Denmark)

    Ross, Stine Dalmann; Gislason, Henrik; Andersen, Niels Gerner

    2016-01-01

    The diet of whiting Merlangius merlangus in the western Baltic Sea was investigated and compared to the diet in the southern North Sea. Clupeids were important prey in both areas, but especially in the western Baltic Sea where they constituted up to 90% of the diet of larger individuals. Gobies......, brown shrimps and polychaetes were the main prey of juveniles in the western Baltic Sea, while a wider range of species were consumed in the North Sea. The shift to piscivory occurred at smaller sizes in the western Baltic Sea and the fish prey consumed was proportionately larger than in the southern...

  7. Regional cost-effectiveness in transboundary water quality management for the Baltic Sea

    DEFF Research Database (Denmark)

    Hasler, Berit; Smart, James Christopher Rudd; Fonnesbech-Wulff, Anders;

    In 2007 HELCOM launched a plan for transboundary management of the Baltic Sea. This plan, called the Baltic Sea Action Plan (BSAP), aims amongst other things, to reduce eutrophication in the different regions of the Baltic Sea by reducing incoming nutrient loads from all discharging drainage basins...... difficult to achieve, and that additional abatement measures are likely to be required to fulfil these targets. The minimised total cost of delivering the achievable load reductions across the 9 Baltic littoral countries is estimated to be 4.69 billion Euros, annually, with substantial differences...

  8. Rotary seal with improved film distribution

    Energy Technology Data Exchange (ETDEWEB)

    Dietle, Lannie Laroy; Schroeder, John Erick

    2015-09-01

    The present invention is a generally circular rotary seal that establishes sealing between relatively rotatable machine components for lubricant retention and environmental exclusion, and incorporates seal geometry that interacts with the lubricant during relative rotation to distribute a lubricant film within the dynamic sealing interface. The features of a variable inlet size, a variable dynamic lip flank slope, and a reduction in the magnitude and circumferentially oriented portion of the lubricant side interfacial contact pressure zone at the narrowest part of the lip, individually or in combination thereof, serve to maximize interfacial lubrication in severe operating conditions, and also serve to minimize lubricant shear area, seal torque, seal volume, and wear, while ensuring retrofitability into the seal grooves of existing equipment.

  9. Rotary seal with improved film distribution

    Science.gov (United States)

    Dietle, Lannie Laroy; Schroeder, John Erick

    2013-10-08

    The present invention is a generally circular rotary seal that establishes sealing between relatively rotatable machine components for lubricant retention and environmental exclusion, and incorporates seal geometry that interacts with the lubricant during relative rotation to distribute a lubricant film within the dynamic sealing interface. The features of a variable inlet size, a variable dynamic lip flank slope, and a reduction in the magnitude and circumferentially oriented portion of the lubricant side interfacial contact pressure zone at the narrowest part of the lip, individually or in combination thereof, serve to maximize interfacial lubrication in severe operating conditions, and also serve to minimize lubricant shear area, seal torque, seal volume, and wear, while ensuring retrofitability into the seal grooves of existing equipment.

  10. REVIEW OF AGING DATA ON EPDM O-RINGS IN THE H1616 SHIPPING PACKAGE

    Energy Technology Data Exchange (ETDEWEB)

    Skidmore, E.

    2012-03-27

    Currently, all H1616 shipping package containers undergo annual re-verification testing, including containment vessel leak testing to verify leak-tightness (<1 x 10{sup -7} ref cc/sec air) as per ANSI N14.5. The purpose of this literature review is to supplement aging studies currently being performed by SRNL on the EPDM O-rings to provide the technical basis for extending annual re-verification testing for the H1616 shipping package and to predict the life of the seals at bounding service conditions. The available data suggest that the EPDM O-rings can retain significant mechanical properties and sealing force at or below bounding service temperatures (169 F or 76 C) beyond the 1 year maintenance period. Interpretation of available data suggests that a service life of at least 2 years and potentially 4-6 years may be possible at bounding temperatures. Seal lifetimes at lower, more realistic temperatures will likely be longer. Being a hydrocarbon elastomer, EPDM O-rings may exhibit an inhibition period due to the presence of antioxidants. Once antioxidants are consumed, mechanical properties and seal performance could decline at a faster rate. Testing is being performed to validate the assumptions outlined in this report and to assess the long-term performance of O-ring seals under actual service conditions.

  11. 表面粗糙度对矩形动密封特性的影响∗%Effect of Surface Roughness on Dynamic Sealing Performance of Rectangular Elastomeric Seals

    Institute of Scientific and Technical Information of China (English)

    张付英; 赵龙; 李佳波

    2015-01-01

    Based on the numerical calculation flow of sealing property coupling of the elastic deformation, hydrodynam⁃ics and interference contact, the dynamic seal performances calculation of rectangular elastomeric seal was realized by u⁃sing Matlab software to program, and the parameters of oil film thickness, leakage and friction were got� The influence of surface roughness on the lubrication state and leakage was analyzed�The calculation results show that when the reciproca⁃ting velocity is constant, the lubrication state between sealing part and shift surface is changed from fluid lubrication into mixed lubrication with the increase of sealing ring roughness, and the leakage of sealing is also increased in a geometric, indicating that the roughness of seals has important influence on the serve life and sealing performance of the sealing ring�Reciprocating motion speed is also one of the key parameters that affect seal performance of rectangular sealing ring, when sealing pressure is certain, the critical speed for no leakage is reduced with the increase of sealing roughness.%基于耦合了密封圈的弹性变形、流体动力分析和过盈接触的密封性能数值计算流程,利用Matlab 软件编程实现矩形动密封特性的数值计算,得到矩形密封圈的油膜厚度、泄漏量及摩擦力等密封性能参数,分析表面粗糙度对矩形密封圈的润滑状态和泄漏量的影响。结果表明:往复运动速度一定时,随着密封圈粗糙度的增加,密封偶合面的润滑状态由流体润滑转变为润滑润滑状态,密封的泄漏量也呈几何式增加,说明粗糙度对密封圈的工作寿命和密封性能有较大的影响;往复运动速度也是影响矩形密封圈密封性能的关键工作参数之一,密封压力一定时,随着粗糙度的增加,不发生泄漏的临界速度降低。

  12. [The "Baltic Frontier" revisited. Power structures and gross-cultural interactions in the Baltic region. Proceedings of the international symposium in Florence, February 29th and March Ist, 2008] / Karsten Brüggemann

    Index Scriptorium Estoniae

    Brüggemann, Karsten, 1965-

    2010-01-01

    Arvustus: The "Baltic Frontier" revisited. Power structures and gross-cultural interactions in the Baltic region. Proceedings of the international symposium in Florence, February 29th and March Ist, 2008. Vienna, 2009

  13. Elastomeric Seal Performance after Terrestrial Ultraviolet Radiation Exposure

    Science.gov (United States)

    Daniels, Christopher C.; Oravec, Heather A.; Mather, Janice L.; Taylor, Shawn C.; Dunlap, Patrick H.

    2015-01-01

    Ultraviolet radiation was evaluated to determine its negative effects on the performance of elastomeric gas pressure seals. The leak rates of the silicone elastomer S0383-70 O-ring test articles were used to quantify the degradation of the seals after exposure to vacuum-ultraviolet and/or middle-to-near-ultraviolet wavelength radiation. Three groups of seals were exposed in terrestrial facilities to 115-165 nm wavelength radiation, 230-500 nm wavelength radiation, or both spectrums, for an orbital spaceflight equivalent of 125 hours. The leak rates of the silicone elastomer S0383-70 seals were quantified and compared to samples that received no radiation. Each lot contained six samples and statistical t-tests were used to determine the separate and combined influences of exposure to the two wavelength ranges. A comparison of the mean leak rates of samples exposed to 115-165 nm wavelength radiation to the control specimens showed no difference, suggesting that spectrum was not damaging. The 230-500 nm wavelength appeared to be damaging, as the mean leak rates of the specimens exposed to that range of wavelengths, and those exposed to the combined 115-165 nm and 230-500 nm spectrums, were significantly different from the leak rates of the control specimens. Most importantly, the test articles exposed to both wavelength spectrums exhibited mean leak rates two orders of magnitude larger than any other exposed specimens, which suggested that both wavelength spectrums are important when simulating the orbital environment.

  14. Leak Rate Performance of Silicone Elastomer O-Rings Contaminated with JSC-1A Lunar Regolith Simulant

    Science.gov (United States)

    Oravec, Heather Ann; Daniels, Christopher C.

    2014-01-01

    Contamination of spacecraft components with planetary and foreign object debris is a growing concern. Face seals separating the spacecraft cabin from the debris filled environment are particularly susceptible; if the seal becomes contaminated there is potential for decreased performance, mission failure, or catastrophe. In this study, silicone elastomer O-rings were contaminated with JSC- 1A lunar regolith and their leak rate performance was evaluated. The leak rate values of contaminated O-rings at four levels of seal compression were compared to those of as-received, uncontaminated, O-rings. The results showed a drastic increase in leak rate after contamination. JSC-1A contaminated O-rings lead to immeasurably high leak rate values for all levels of compression except complete closure. Additionally, a mechanical method of simulant removal was examined. In general, this method returned the leak rate to as-received values.

  15. Groups, rings, modules

    CERN Document Server

    Auslander, Maurice

    2014-01-01

    This classic monograph is geared toward advanced undergraduates and graduate students. The treatment presupposes some familiarity with sets, groups, rings, and vector spaces. The four-part approach begins with examinations of sets and maps, monoids and groups, categories, and rings. The second part explores unique factorization domains, general module theory, semisimple rings and modules, and Artinian rings. Part three's topics include localization and tensor products, principal ideal domains, and applications of fundamental theorem. The fourth and final part covers algebraic field extensions

  16. On Weakly Semicommutative Rings*

    Institute of Scientific and Technical Information of China (English)

    CHEN WEI-XING; CUI SHU-YING

    2011-01-01

    A ring R is said to be weakly scmicommutative if for any a, b ∈ R,ab = 0 implies aRb C_ Nil(R), where Nil(R) is the set of all nilpotcnt elements in R.In this note, we clarify the relationship between weakly semicommutative rings and NI-rings by proving that the notion of a weakly semicommutative ring is a proper generalization of NI-rings. We say that a ring R is weakly 2-primal if the set of nilpotent elements in R coincides with its Levitzki radical, and prove that if R is a weakly 2-primal ring which satisfies oα-condition for an endomorphism α of R (that is, ab = 0 (←→) aα(b) = 0 where a, b ∈ R) then the skew polynomial ring R[π; αα]is a weakly 2-primal ring, and that if R is a ring and I is an ideal of R such that I and R/I are both weakly semicommutative then R is weakly semicommutative.Those extend the main results of Liang et al. 2007 (Taiwanese J. Math., 11(5)(2007),1359-1368) considerably. Moreover, several new results about weakly semicommutative rings and NI-rings are included.

  17. Hermetic seal for a shaft

    Science.gov (United States)

    Lombardi, F. (Inventor)

    1982-01-01

    An hermetic seal for a linear rod having a portion thereof projected axially through a port defined in a wall for a pressure chamber and supported thereby for omni-directional motion is described. The seal is characterized by a resilient, impervious, cylindrical body having a first section concentrically related to the shaft and integrally affixed thereto comprising a linear ordered array of annular flutes. A second section integrally is affixed to the wall of the chamber and concentrically related to the port comprising a second linear ordered array of annular flutes. A third section is interposed between the first and second sections and integrally affixed in coaxial alignment therewith comprising an annular ordered array of linear flutes concentrically related to the shaft, whereby axial, angular, and pivotal motion of the rod is accommodated.

  18. [History of pedagogy and educational sciences in the Baltic countries from 1940 to 1990. An overview] / Mare Oja

    Index Scriptorium Estoniae

    Oja, Mare, 1960-

    2014-01-01

    Arvustus: History of pedagogy and educational sciences in the Baltic countries from 1940 to 1990. An overview. Hrsg. im Auftrag der Baltic Association of Historians of Pedagogy von Vadim Rõuk und Vidimantas Raudys. Verlag RaKa. Riga 2013

  19. Fisheries management responses to climate change in the Baltic Sea

    DEFF Research Database (Denmark)

    Thøgersen, Thomas Talund; Hoff, Ayoe; Frost, Hans S.

    2015-01-01

    The long term management plan for cod in the eastern Baltic Sea was introduced in 2007 to ensure the full reproductive capacity of cod and an economically viable fishing industry. If these goals are to be fulfilled under changing environmental conditions, a readjustment of the current management...... plan may be needed. Therefore, this paper investigates the economic impacts of managing the cod, sprat and herring stocks in the eastern Baltic Sea, given on-going climate change, which is known to affect cod recruitment negatively. It is shown that climate change may have severe biological...... scenarios in which the economic consequences of different management objectives for the fishing fleets are assessed through a dynamic multi-species and multi-fleet bio-economic assessment model that include both species interactions and climate change....

  20. The ethno-demographic status of the Baltic States.

    Science.gov (United States)

    Mezs, I; Bunkse, E; Rasa, K

    1994-05-01

    "The essay examines historic and current ethnodemographic trends in spatial and cultural contexts in the Baltic States. Fifty years of Soviet rule, with deliberate policies to dilute the relative homogeneity of the Balts through ethnocide, in-migration, and political dominance by Moscow, has left tensions between citizens of the Baltic States and illegal immigrants, mostly Russians. Estonians, and Latvians, in particular, fear ethnic and cultural extinction. The process of ethnic dilution and mixing under the Soviets is examined in terms of rural-urban contexts, the workplace, employment, housing, and education. Europe's smallest ethnic group, the Livs of Latvia, is also examined. Current demographic trends are analysed and prospects for ethnic harmony in these multi-ethnic societies are interpreted. A recurrent theme is that Latvia, with 52% of the population Latvian, is facing the most difficulties; Lithuania, with 80% Lithuanians, the least."

  1. Microplastic concentrations in beach sediments along the German Baltic coast.

    Science.gov (United States)

    Stolte, Andrea; Forster, Stefan; Gerdts, Gunnar; Schubert, Hendrik

    2015-10-15

    The contamination with microplastic particles and fibres was evaluated on beaches along the German Baltic coast. Sediments were sampled near the Warnow and Oder/Peene estuaries, on Rügen island and along the Rostock coast to derive possible entry pathways. Seasonal variations were monitored along the Rostock coast from March to July 2014. After density separation in saline solution, floating particles were found to be dominated by sand grains. Water surface tension is shown to be sufficient to explain floatation of grains with sizes less than 1.5mm. Selecting intensely coloured particles and fibres, we find lower limits of the microplastic concentrations of 0-7 particles/kg and 2-11 fibres/kg dry sediment. The largest microplastic contaminations are measured at the Peene outlet into the Baltic Sea and in the North Sea Jade Bay. City discharges, industrial production sites, fishing activity and tourism are the most likely sources for the highest microplastic concentrations.

  2. Egg mortality: predation and hydrography in the central Baltic

    DEFF Research Database (Denmark)

    Voss, R.; Hinrichsen, H.-H.; Stepputtis, D.;

    2011-01-01

    during the egg phase to be of critical importance. Two years of extensive field investigations in the Bornholm Basin, central Baltic Sea, were undertaken. In 2002, a typical stagnation situation characterized by low salinity and poor oxygen conditions was investigated, and in early 2003, a major inflow...... of North Sea water completely changed the hydrographic conditions by increasing salinity and oxygen content, thereby altering ecological conditions. The goal was to quantify egg mortality caused by predation and hydrography, and to compare these estimates with independent estimates based on cohort analysis....... Results indicated high intra-annual variability in egg mortality. Cod and sprat egg mortality responded differently to the major Baltic inflow: mortality related to hydrographic conditions increased for sprat and decreased for cod. On the other hand, predation mortality during peak spawning decreased...

  3. Light scattering in Baltic crude oil - seawater emulsion

    Directory of Open Access Journals (Sweden)

    Adam Stelmaszewski

    2009-09-01

    Full Text Available The paper discusses the scattering of radiation by a Baltic crude oil - seawater emulsion. The scattering spectrum calculated using the Mie solution in the spectral range from 380 nm to 730 nm is compared with the measured spectrum of light scattered through a right angle. Spectra in the wavelength range from 210 nm to 730 nm were measured using a spectrofluorimeter for fresh and stored samples of the Baltic crude oil emulsion. Scattering increases with wavelength in the UV range and then decreases slightly with the wavelength of visible light. The result of the calculation is similar to the measured spectra. Both the calculated and measured spectra display numerous relative extremes throughout the spectral area. Light scattering in the emulsion decreases during storage as the oil concentration in the medium diminishes. The results also demonstrate that the single scattering model describes the phenomenon correctly.

  4. Fisheries management responses to climate change in the Baltic Sea

    DEFF Research Database (Denmark)

    Thøgersen, Thomas Talund; Hoff, Ayoe; Frost, Hans S.

    2015-01-01

    plan may be needed. Therefore, this paper investigates the economic impacts of managing the cod, sprat and herring stocks in the eastern Baltic Sea, given on-going climate change, which is known to affect cod recruitment negatively. It is shown that climate change may have severe biological...... scenarios in which the economic consequences of different management objectives for the fishing fleets are assessed through a dynamic multi-species and multi-fleet bio-economic assessment model that include both species interactions and climate change.......The long term management plan for cod in the eastern Baltic Sea was introduced in 2007 to ensure the full reproductive capacity of cod and an economically viable fishing industry. If these goals are to be fulfilled under changing environmental conditions, a readjustment of the current management...

  5. THE GREGARIOUS BEHAVIOR OF INVESTORS FROM BALTIC STOCK MARKETS

    OpenAIRE

    Pece Andreea Maria

    2015-01-01

    The main objective of this research is to investigate market participants’ gregarious behaviour in Baltic stock markets, namely Lithuania, Latvia and Estonia during the period January 2003-December 2013. The herding behaviour derives from the investors’ irrationality, who trade financial assets based on their positive expectations about prices future growth, generating manias among other market participants, thus ignoring the real return rates and the risk levels of their investments.The inve...

  6. Use of bioenergy in the Baltic Sea region. Conference proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Barz, M.; Ahlhaus, M. (eds.)

    2006-07-01

    The actual situation in our world can shortly be characterized by growing population and increasing energy demand, mainly covered by fossil fuels. This results in environmental as well as climate change problems. Renewable energies offer many opportunities to overcome these problems - they can provide heat and electricity as well as automotive fuels in environmentally friendly systems and thus contribute to lower the fossil fuels dependency. Biomass as the oldest renewable energy of mankind is still playing a dominant role as an energy carrier in some African and Asian regions, where biofuels are still used in traditional ways - mainly for cooking. On the other hand biomass has a huge potential to become a more important energy resource even in industrialized countries. All over the world the opportunities of biomass are accepted and biomass has become a common term in politics resulting in new strategic analyses, political documents, legislative actions and funding programs. A lot of modern and new high-tech solutions for bioenergy systems are already developed and others are under research. Aims of the actual developments are new bioenergy systems on the basis of regional biomass potentials in rural regions. The Baltic Sea Region offers a high potential to produce biofuels for different applications to fit the growing demand of heat, electricity and fuels. In combination with its industry and engineering skills the Baltic Sea Region is predestinated as a nucleus for further development and demonstration of advanced bioenergy solutions. In the result of the conference ''Contribution of Agriculture to Energy Production'', held in Tallinn, Estonia in October 2005 representatives from policy, economy and science identified a high potential and demand for bioenergy solutions and realized the necessity of establishment of an international network (Baltic Bioenergy Net - BaBEt) for information and know-how transfer between the Baltic States to foster

  7. Biomethanation of Red Algae from the Eutrophied Baltic Sea

    OpenAIRE

    Biswas, Rajib

    2009-01-01

    In the semi-enclosed Baltic Sea, excessive filamentous macro-algal biomass growth as a result of eutrophication is an increasing environmental problem. Drifting huge masses of red algae of the genera Polysiphonia, Rhodomela, and Ceramium accumulate on the open shore, up to five tones of algae per meter beach. During the aerobic decomposition of these algal bodies, large quantities of red colored effluents leak into the water what are toxic for the marine environment. In this study, feasibilit...

  8. Emission Permits trade between the Nordic and Baltic Countries

    Energy Technology Data Exchange (ETDEWEB)

    Alm, Leif Kristian

    2000-05-01

    A bottom-up technology oriented model of the energy systems in the Nordic and Baltic countries have been constructed and used for analysing an optimal set of energy and emission trading within the region. The model used is MARKAL, which has been developed within the IEA-ETSAP. The analyses are based on national emission levels agreed on in the Kyoto protocol (and the following burden sharing negotiations within the European Union), and with an additional strengthening after 2010. Only energy related CO{sub 2} emissions are explicitly considered. Nuclear power in Sweden is assumed to be phased out. The results show that especially Norway and Sweden have large abatement costs when acting alone, whale the Baltic countries will probably not need to take domestic actions due to the Kyoto protocol if they act alone, as the restructuring of their economies in the beginning of the 1990ties cut emissions (and their economies) dramatically. It is shown that emission trading among the Nordic and Baltic countries can reduce abatement costs among the Nordic countries significantly, possibly down to a level equivalent to a world market (Annex I) permit price. Extending the Nordic common electricity market to Balticum will have minor influence on overall energy system costs. There is no pronounced direction for net electricity flow between the Nordic and Baltic countries. High marginal costs during peak hours in Balticum indicate that imports of Nordic hydro power during peak-hours could be a cost-effective option. This possibility could be implemented with a subsea AC/DC connection between Sweden and Latvia. It is politically viable to develop more hydropower in Norway, this country will be the major electricity exporter in the region, while Sweden will be the main importer. Changing scenario assumptions, i.e. no more Norwegian hydropower, but life extension of Swedish nuclear power, could change this picture. (author)

  9. The Security Concerns of the Baltic States as NATO Allies

    Science.gov (United States)

    2013-08-01

    national cyber attack on Estonia, apparently mounted from Russia, is another point of friction. In the Baltic States, there are large Russian...results when it is presented as an attrac- tive proposition to the local populations and govern- ments. Soft power backed up by lies, bullying , and...All the 35 Estonians noted that national cyber protection was an important security concern. This is understandable, because in April and May 2007

  10. Active bypass flow control for a seal in a gas turbine engine

    Energy Technology Data Exchange (ETDEWEB)

    Ebert, Todd A.; Kimmel, Keith D.

    2017-03-14

    An active bypass flow control system for controlling bypass compressed air based upon leakage flow of compressed air flowing past an outer balance seal between a stator and rotor of a first stage of a gas turbine in a gas turbine engine is disclosed. The active bypass flow control system is an adjustable system in which one or more metering devices may be used to control the flow of bypass compressed air as the flow of compressed air past the outer balance seal changes over time as the outer balance seal between the rim cavity and the cooling cavity wears In at least one embodiment, the metering device may include an annular ring having at least one metering orifice extending therethrough, whereby alignment of the metering orifice with the outlet may be adjustable to change a cross-sectional area of an opening of aligned portions of the outlet and the metering orifice.

  11. Design optimization of seal structure for sealing liquid by magnetic fluids

    Science.gov (United States)

    Liu, Tonggang; Cheng, Yusheng; Yang, Zhiyi

    2005-03-01

    The durability of the magnetic fluid seal clearly decreases when sealing another liquid because of the interface instability caused by the applied magnetic field and the velocity difference of the two liquids. With an intention to establish a stable interface during sealing liquid, a new magnetic fluid seal was developed in this paper. The parameters of the structure were optimized by a simulation apparatus. And the magnetic fluid seal designed based on the optimum parameters shows good performance and long life for sealing lubricating oil.

  12. Deoxygenation of the Baltic Sea during the last century.

    Science.gov (United States)

    Carstensen, Jacob; Andersen, Jesper H; Gustafsson, Bo G; Conley, Daniel J

    2014-04-15

    Deoxygenation is a global problem in coastal and open regions of the ocean, and has led to expanding areas of oxygen minimum zones and coastal hypoxia. The recent expansion of hypoxia in coastal ecosystems has been primarily attributed to global warming and enhanced nutrient input from land and atmosphere. The largest anthropogenically induced hypoxic area in the world is the Baltic Sea, where the relative importance of physical forcing versus eutrophication is still debated. We have analyzed water column oxygen and salinity profiles to reconstruct oxygen and stratification conditions over the last 115 y and compare the influence of both climate and anthropogenic forcing on hypoxia. We report a 10-fold increase of hypoxia in the Baltic Sea and show that this is primarily linked to increased inputs of nutrients from land, although increased respiration from higher temperatures during the last two decades has contributed to worsening oxygen conditions. Although shifts in climate and physical circulation are important factors modulating the extent of hypoxia, further nutrient reductions in the Baltic Sea will be necessary to reduce the ecosystems impacts of deoxygenation.

  13. Numerical Analysis of Magnetic Fluid Sealing Performance

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The sealing performance of magnetic fluid is related to the magnetic fluid itself. Many factors can influence the magnetic field and the seal pressure differences of magnetic fluid seals, such as the sealing gap, the shaft eccentricity, the shaft diameter, the volume of the magnetic fluid and the centrifugal force. These factors are analyzed by numerical computation . When the seal material and structure are the same, the seal pressure difference is directly proportional to the magnetic field intensity and the saturation magnetization of the magnetic fluid. The sealing performance of the magnetic fluid will reduce with the increase of the sealing gap and shaft eccentricity. The sealing performance will increase with the volume of the magnetic fluid and decrease with the increase of the shaft diameter taking gravity into account. The increase of the shaft diameter is the same as the reduction of the volume of the magnetic fluid. The magnetic fluid cross-section can change because of the centrifugal force. Some improvements can reduce the influence of the centrifugal force. The centrifugal force can be utilized to improve the sealing performance.

  14. Physics of quantum rings

    CERN Document Server

    Fomin, Vladimir M

    2013-01-01

    This book deals with a new class of materials, quantum rings. Innovative recent advances in experimental and theoretical physics of quantum rings are based on the most advanced state-of-the-art fabrication and characterization techniques as well as theoretical methods. The experimental efforts allow to obtain a new class of semiconductor quantum rings formed by capping self-organized quantum dots grown by molecular beam epitaxy. Novel optical and magnetic properties of quantum rings are associated with non-trivial topologies at the nanoscale. An adequate characterization of quantum rings is po

  15. Envelopes of Commutative Rings

    Institute of Scientific and Technical Information of China (English)

    Rafael PARRA; Manuel SAOR(I)N

    2012-01-01

    Given a significative class F of commutative rings,we study the precise conditions under which a commutative ring R has an F-envelope.A full answer is obtained when.F is the class of fields,semisimple commutative rings or integral domains.When F is the class of Noetherian rings,we give a full answer when the Krull dimension of R is zero and when the envelope is required to be epimorphic.The general problem is reduced to identifying the class of non-Noetherian rings having a monomorphic Noetherian envelope,which we conjecture is the empty class.

  16. RING PROXY SIGNATURES

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Proxy signatures have been used to enable the transfer of digital signing power within some context and ring signatures can be used to provide the anonymity of a signer. By combining the functionalities of proxy signatures and ring signatures, this paper introduces a new concept, named ring proxy signature, which is a proxy signature generated by an anonymous member from a set of potential signers. The paper also constructs the first concrete ring proxy signature scheme based on the provably secure Schnorr's signatures and two ID-based ring proxy signature schemes. The security analysis is provided as well.

  17. Saturn's largest ring.

    Science.gov (United States)

    Verbiscer, Anne J; Skrutskie, Michael F; Hamilton, Douglas P

    2009-10-22

    Most planetary rings in the Solar System lie within a few radii of their host body, because at these distances gravitational accelerations inhibit satellite formation. The best known exceptions are Jupiter's gossamer rings and Saturn's E ring, broad sheets of dust that extend outward until they fade from view at five to ten planetary radii. Source satellites continuously supply the dust, which is subsequently lost in collisions or by radial transport. Here we report that Saturn has an enormous ring associated with its outer moon Phoebe, extending from at least 128R(S) to 207R(S) (Saturn's radius R(S) is 60,330 km). The ring's vertical thickness of 40R(S) matches the range of vertical motion of Phoebe along its orbit. Dynamical considerations argue that these ring particles span the Saturnian system from the main rings to the edges of interplanetary space. The ring's normal optical depth of approximately 2 x 10(-8) is comparable to that of Jupiter's faintest gossamer ring, although its particle number density is several hundred times smaller. Repeated impacts on Phoebe, from both interplanetary and circumplanetary particle populations, probably keep the ring populated with material. Ring particles smaller than centimetres in size slowly migrate inward and many of them ultimately strike the dark leading face of Iapetus.

  18. The contraceptive vaginal ring.

    Science.gov (United States)

    Edwardson, Jill; Jamshidi, Roxanne

    2010-03-01

    The contraceptive vaginal ring offers effective contraception that is self-administered, requires less frequent dosing than many other forms of contraception, and provides low doses of hormones. NuvaRing (Organon, Oss, The Netherlands), the only contraceptive vaginal ring approved for use in the United States, contains etonogestrel and ethinyl estradiol. It is inserted into the vagina for 3 weeks, followed by a 1-week ring-free period, and works by inhibiting ovulation. Most women note a beneficial effect on bleeding profiles and are satisfied with NuvaRing. Commonly reported adverse events include vaginitis, leukorrhea, headaches, and device-related events such as discomfort. Serious adverse events are rare. In Chile and Peru, progesterone-only vaginal contraceptive rings are available for nursing women. Studies are ongoing examining new formulations of vaginal contraceptive rings.

  19. Certain near-rings are rings, II

    Directory of Open Access Journals (Sweden)

    Howard E. Bell

    1986-01-01

    Full Text Available We investigate distributively-generated near-rings R which satisfy one of the following conditions: (i for each x,y∈R, there exist positive integers m, n for which xy=ymxn; (ii for each x,y∈R, there exists a positive integer n such that xy=(yxn. Under appropriate additional hypotheses, we prove that R must be a commutative ring.

  20. The architecture of the adhesive apparatus of cultured osteoclasts: from podosome formation to sealing zone assembly.

    Directory of Open Access Journals (Sweden)

    Chen Luxenburg

    Full Text Available BACKGROUND: Osteoclasts are bone-degrading cells, which play a central role in physiological bone remodeling. Unbalanced osteoclast activity is largely responsible for pathological conditions such as osteoporosis. Osteoclasts develop specialized adhesion structures, the so-called podosomes, which subsequently undergo dramatic reorganization into sealing zones. These ring-like adhesion structures, which delimit the resorption site, effectively seal the cell to the substrate forming a diffusion barrier. The structural integrity of the sealing zone is essential for the cell ability to degrade bone, yet its structural organization is poorly understood. PRINCIPAL FINDINGS: Combining high-resolution scanning electron microscopy with fluorescence microscopy performed on the same sample, we mapped the molecular architecture of the osteoclast resorptive apparatus from individual podosomes to the sealing zone, at an unprecedented resolution. Podosomes are composed of an actin-bundle core, flanked by a ring containing adhesion proteins connected to the core via dome-like radial actin fibers. The sealing zone, hallmark of bone-resorbing osteoclasts, consists of a dense array of podosomes communicating through a network of actin filaments, parallel to the substrate and anchored to the adhesive plaque domain via radial actin fibers. SIGNIFICANCE: The sealing zone of osteoclasts cultured on bone is made of structural units clearly related to individual podosomes. It differs from individual or clustered podosomes in the higher density and degree of inter-connectivity of its building blocks, thus forming a unique continuous functional structure connecting the cell to its extracellular milieu. Through this continuous structure, signals reporting on the substrate condition may be transmitted to the whole cell, modulating the cell response under physiological and pathological conditions.

  1. Investigation into the Impact of n-Decane, Decalin, and Isoparaffinic Solvent on Elastomeric Sealing Materials

    Directory of Open Access Journals (Sweden)

    Yue Liu

    2012-01-01

    Full Text Available One of the crucial aspects in the adoption of alternative fuels (e.g., GtL fuel in aviation industry is to investigate their compatibility with elastomeric materials used in current gas turbine engines. This study employed stress relaxation technique to investigate the effects of three solvents, namely, decalin (cycloparaffin, n-decane (normal paraffin, and ShellSol T solvent (isoparaffins on O-rings made from different materials. Results indicated that both fluorosilicone and fluorocarbon O-rings showed excellent compatibility with all 25 blends tested. The stress relaxation characteristic of nitrile O-ring was highly dependent on the composition of the solvents; the more decalin (n-decane is in the blend, the better (worse its sealing performance becomes. Effects of the three solvents presented in the tests indicated aromatics are not the only compounds that can swell nitrile O-ring. It is also important to notice that although decalin presents good O-ring swelling ability, it does not mean all cycloparaffins have the same property. n-decane also showed certain O-ring swelling ability but its main effect during the polymer-fuel interaction process is to extract materials out of nitrile O-ring. Isoparaffins do not participate in the O-ring swelling process. They only extract polymer materials; however, its extraction ability is relatively weaker than n-decane.

  2. Coalbed methane reservoir boundaries and sealing mechanism

    Institute of Scientific and Technical Information of China (English)

    SU Xianbo; LIN Xiaoying; LIU Shaobo; SONG Yan

    2005-01-01

    It is important to investigate the coalbed methane reservoir boundaries for the classification, exploration, and development of the coalbed methane reservoir.Based on the investigation of the typical coalbed methane reservoirs in the world, the boundaries can be divided into four types: hydrodynamic boundary, air altered boundary,permeability boundary, and fault boundary. Hydrodynamic and air altered boundaries are ubiquitous boundaries for every coalbed methane reservoir. The four types of the fault sealing mechanism in the petroleum geological investigation (diagen- esis, clay smear, juxtaposition and cataclasis) are applied to the fault boundary of the coalbed methane reservoir. The sealing mechanism of the open fault boundary is the same with that of the hydrodynamic sealing boundary.The sealing mechanism of the permeability boundary is firstly classified into capillary pressure sealing and hydrocarbon concentration sealing. There are different controlling boundaries in coalbed methane reservoirs that are in different geological backgrounds. Therefore, the coalbed methane reservoir is diversiform.

  3. Air riding seal for a turbine

    Energy Technology Data Exchange (ETDEWEB)

    Mills, Jacob A; Brown, Wesley D; Sexton, Thomas D; Jones, Russell B

    2016-07-19

    An air riding seal between a rotor and a stator in a turbine of a gas turbine engine, where an annular piston is movable in an axial direction within a housing that extends from the stator, and a bellows is secured to the annular piston to form a flexible air passageway from a compressed air inlet through the annular piston and into a cushion cavity that forms an air riding seal between the annular piston and the rotor sealing surface. In another embodiment, a flexible seal secured to and extending from the annular piston forms a sealing surface between the annular piston chamber and the annular piston to provide a seal and allow for axial movement.

  4. Neutrosophic LA-Semigroup Rings

    Directory of Open Access Journals (Sweden)

    Mumtaz Ali

    2015-01-01

    Full Text Available Neutrosophic LA-semigroup is a midway structure between a neutrosophic groupoid and a commutative neutrosophic semigroup. Rings are the old concept in algebraic structures. We combine the neutrosophic LA-semigroup and ring together to form the notion of neutrosophic LA-semigroup ring. Neutrosophic LAsemigroup ring is defined analogously to neutrosophic group ring and neutrosophic semigroup ring.

  5. On Exchange QB∞-Rings

    Institute of Scientific and Technical Information of China (English)

    Huanyin Chen

    2007-01-01

    In this paper, we introduce a new class of rings, the QB∞-rings. We investigate necessary and sufficient conditions under which an exchange ring is a QB∞-ring. The modules over an exchange QB∞-ring are studied. Also, we prove that every regular square matrix over an exchange QB∞-ring admits a diagonal reduction by pseudo-invertible matrices.

  6. Impact of climate change on the Baltic Sea ecosystem over the past 1,000 years

    NARCIS (Netherlands)

    Kabel, K.; Moros, M.; Porsche, C.; Neumann, T.; Adolphi, F.; Andersen, T.J.; Siegel, H.; Gerth, M.; Leipe, T.; Jansen, E.; Sinninghe Damsté, J.S.

    2012-01-01

    Climate change has a strong impact on ecosystem health, particularly in marginal seas(1) such as the Baltic, for example causing the spreading of anoxic areas (oxygen-free areas, the so-called dead zones) through strong feedbacks. Marked ecosystem changes in the Baltic Sea have been recorded in the

  7. US Baltic Foundation award winners from Estonia are Arvo Pärt and Enn Kunila

    Index Scriptorium Estoniae

    2010-01-01

    Washingtonis toimunud tänavusel U.S Baltic Foundationi auhinnagalal tunnustati kahte eestlast: helilooja Arvo Pärti auhinnaga Baltimaade kuvandi rikastamise eest (Baltic Image Enhancement Award) ja ettevõtjast kunstikollektsionääri Enn Kunilat Baltimaade filantroopiaauhinnaga

  8. USBF recognized President Ilves for promoting relations between the Baltic countries and the United States

    Index Scriptorium Estoniae

    2008-01-01

    President Toomas Hendrik Ilves pälvis Balti riikide ja Ameerika Ühendriikide suhete edendamise eest Ameerika-Balti Fondi (USBF - The United States-Baltic Foundation) autasu - Baltic Statesmanship Award'i. Vabariigi President töövisiidil Ameerika Ühendriikides 17.-23.04.2008

  9. Baltic Heritage Network : die Pflege des exilbaltischen Kulturerbes - Zwischenbilanz und Zukunftsperspektiven / Piret Noorhani

    Index Scriptorium Estoniae

    Noorhani, Piret, 1960-

    2008-01-01

    Välisbalti kultuuripärandi portaal Baltic Heritage Network, mis on mitmekeelne portaal koondamaks informatsiooni Balti diasporaa kultuuripärandi leidumuse ja sellealase tegevuse kohta. Rahvusvahelise ja siseriikliku koostöö laiendamiseks ja tegevuste koordineerimiseks loodi jaanuaris 2008 mittetulundusühing Baltic Heritage Network, kuhu kuulub praegu liikmeid kõigist kolmest Balti riigist.

  10. Stock recruitment relationships for cod ( Gadus morhua L.) in the central Baltic Sea incorporating environmental variability

    DEFF Research Database (Denmark)

    Jarre, Astrid; Wieland, Kai; MacKenzie, Brian;

    2000-01-01

    Recruitment of central/eastern Baltic cod critically depends on favourable oceanographic conditions in the deeper basins of the Baltic Sea creating a suitable habitat for the development of early life stages. The decline in the size of the spawning stock since the mid-1980s initiated a series...

  11. NEW POLIMER SEALING FLUID STOPS MUD LOSS

    Directory of Open Access Journals (Sweden)

    Stanislaw Stryczek

    1989-12-01

    Full Text Available This paper deals with a composition of sealing fluid, prepared from acrylic acid salt water solution Solakryl M. Laboratory test results of technological properties of its modifications with mineral agents are shown. A new method of sealing mud loss operations with given sealing liquid is discussed along with comments on effects of its use for stopping mud loss in case of freeze-well drilling is described (the paper is published in Croatian.

  12. Influence of Rocket Engine Characteristics on Shaft Sealing Technology Needs

    Science.gov (United States)

    Keba, John E.

    1999-01-01

    This paper presents viewgraphs of The Influence of Rocket Engine Characteristics on Shaft Sealing Technology Needs. The topics include: 1) Rocket Turbomachinery Shaft Seals (Inter-Propellant-Seal (IPS) Systems, Lift-off Seal Systems, and Technology Development Needs); 2) Rocket Engine Characteristics (Engine cycles, propellants, missions, etc., Influence on shaft sealing requirements); and 3) Conclusions.

  13. A reliable sealing method for microbatteries

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yuxing; Cartmell, Samuel; Li, Qiuyan; Xiao, Jie; Li, Huidong; Deng, Zhiqun Daniel; Zhang, Ji-Guang

    2017-02-01

    With continuous downsizing of electronic devices, lithium batteries of traditional shapes cannot meet the demand where small-size high energy density batteries are needed. Conventional sealing methods become increasingly difficult to apply and impose high processing cost as the size of batteries decreases. In this report, a facile sealing method is proposed and demonstrated in CFx/Li mini-batteries. The method employs a temporary barrier to liquid electrolytes while relies on the epoxies/cell casings bond for the hermetic sealing. Cells sealed by this method show no degradation for an extended period of storage time.

  14. Self-acting geometry for noncontact seals

    Science.gov (United States)

    Allen, G. P.

    1981-01-01

    Performance ot two self acting seal designs for a liquid oxygen (LOX) turbopump was predicted over ranges of pressure differential and speed. Predictions were compared with test results. Performance of a radial face seal for LOX was predicted up to 448 N/cu cm and 147 m/sec. Performance of a segmented circumferential seal for helium was predicted up to 69 N/cu cm and 189 m/sec. Results confirmed predictions of noncontact operation. Qualitative agreement between test and analysis was found. The LOX face seal evidently operated with mostly liquid in the self acting geometry and mostly gas across the dam.

  15. Byzantine seals from the Ras fortress

    Directory of Open Access Journals (Sweden)

    Ivanišević Vujadin

    2013-01-01

    Full Text Available In this paper, seals found at the location of the Ras fortress (Tvrđava Ras have been published. Inscriptions on these seals show that they used to belong to persons which could be identified with certain military commanders who served under Alexios I Komnenos. The seals in question are: the seals of protonobelissimos Eustathios Kamytzes, Constantine Dalassenos Doukas, protoproedros and doux Constantine Kekaumenos and a certain person called Alexios. [Projekat Ministarstva nauke Republike Srbije, br. 177021 i br. 177032

  16. Artistic Alliances and Revolutionary Rivalries in the Baltic Art World, 1890-1914

    Directory of Open Access Journals (Sweden)

    Bart Pushaw

    2016-11-01

    Full Text Available In the areas now known as Estonia and Latvia, art remained a matter for the Baltic German minority throughout the nineteenth century. When ethnic Estonian and Latvian artists gained prominence in the late 1890s, their presence threatened Baltic German hegemony over the region’s culture. In 1905, revolution in the Russian Empire spilled into the Baltic Provinces, sparking widespread anti-German violence. The revolution also galvanized Latvian and Estonian artists towards greater cultural autonomy and independence from Baltic German artistic institutions. This paper argues that the situation for artists before and after the 1905 revolution was not simply divisive along ethnic lines, as some nationalist historians have suggested. Instead, this paper examines how Baltic German, Estonian and Latvian artists oscillated between common interests, inspiring rivalries, and politicized conflicts, questioning the legitimacy of art as a universalizing language in multicultural societies.

  17. Climate change effects on the Baltic Sea borderland between land and sea.

    Science.gov (United States)

    Strandmark, Alma; Bring, Arvid; Cousins, Sara A O; Destouni, Georgia; Kautsky, Hans; Kolb, Gundula; de la Torre-Castro, Maricela; Hambäck, Peter A

    2015-01-01

    Coastal habitats are situated on the border between land and sea, and ecosystem structure and functioning is influenced by both marine and terrestrial processes. Despite this, most scientific studies and monitoring are conducted either with a terrestrial or an aquatic focus. To address issues concerning climate change impacts in coastal areas, a cross-ecosystem approach is necessary. Since habitats along the Baltic coastlines vary in hydrology, natural geography, and ecology, climate change projections for Baltic shore ecosystems are bound to be highly speculative. Societal responses to climate change in the Baltic coastal ecosystems should have an ecosystem approach and match the biophysical realities of the Baltic Sea area. Knowledge about ecosystem processes and their responses to a changing climate should be integrated within the decision process, both locally and nationally, in order to increase the awareness of, and to prepare for climate change impacts in coastal areas of the Baltic Sea.

  18. Well sealing via thermite reactions

    Energy Technology Data Exchange (ETDEWEB)

    Lowry, William Edward; Dunn, Sandra Dalvit

    2016-11-15

    A platform is formed in a well below a target plug zone by lowering a thermite reaction charge into the well and igniting it, whereby the products of the reaction are allowed to cool and expand to form a platform or support in the well. A main thermite reaction charge is placed above the platform and ignited to form a main sealing plug for the well. In some embodiments an upper plug is formed by igniting an upper thermite reaction charge above the main thermite reaction charge. The upper plug confines the products of ignition of the main thermite reaction charge.

  19. Magnetohydrodynamic (MHD) channel corner seal

    Science.gov (United States)

    Spurrier, Francis R.

    1980-01-01

    A corner seal for an MHD duct includes a compressible portion which contacts the duct walls and an insulating portion which contacts the electrodes, sidewall bars and insulators. The compressible portion may be a pneumatic or hydraulic gasket or an open-cell foam rubber. The insulating portion is segmented into a plurality of pieces of the same thickness as the electrodes, insulators and sidewall bars and aligned therewith, the pieces aligned with the insulator being of a different size from the pieces aligned with the electrodes and sidewall bars to create a stepped configuration along the corners of the MHD channel.

  20. Sealed nickel-cadmium battery

    Energy Technology Data Exchange (ETDEWEB)

    1989-08-15

    Overcharge protection, and especially the chargeability of a sealed Ni/Cd battery with high currents is improved by rolling a carbon-containing powdered material into the surface of the negative electrode, which material catalyzes the reduction of oxygen. Wetting of the electrode with a Tylose dispersion prior to application of the powder (by powdering, vibration or in an agitator) improves the adhesion of the powder. The cadmium electrode thus prepared combines in itself the functions of a negative principal electrode and of an auxiliary oxygen electrode.

  1. Albinistic common seals (Phoca vitulina) and melanistic grey seals (Halichoerus grypus) rehabilitated in the Netherlands

    NARCIS (Netherlands)

    Osinga, Nynke; 't Hart, Pieter; Vader, Pieter C. van Voorst

    2010-01-01

    The Seal Rehabilitation and Research Centre (SRRC) in Pieterburen, The Netherlands, rehabilitates seals from the waters of the Wadden Sea, North Sea and Southwest Delta area. Incidental observations of albinism and melanism in common and grey seals are known from countries surrounding the North Sea.

  2. Seals at sea: modelling seal distribution in the German bight based on aerial survey data

    NARCIS (Netherlands)

    Herr, H.; Scheidat, M.; Lehnert, K.; Siebert, U.

    2009-01-01

    The Wadden Sea is an important habitat for harbour seals and grey seals. They regularly haul-out on sandbanks and islands along the coast. Comparably little is known about the time seals spend at sea and how they use the remainder of the North Sea. Yet, human activity in offshore waters is increasin

  3. Space Shuttle Orbital Maneuvering Subsystem (OMS) Engine Propellant Leakage Ball-Valve Shaft Seals

    Science.gov (United States)

    Lueders, Kathy; Buntain, Nick; Fries, Joseph (Technical Monitor)

    1999-01-01

    Evidence of propellant leakage across ball-valve shaft seals has been noted during the disassembly of five flight engines and one test engine at the NASA Lyndon B. Johnson Space Center, White Sands Test Facility. Based on data collected during the disassembly of these five engines, the consequences of propellant leakage across the ball-valve shaft seals can be divided into four primary areas of concern: Damage to the ball-valve pinion shafts, damage to sleeved bearings inside the ball-valve and actuator assemblies, degradation of the synthetic rubber o-rings used in the actuator assemblies, and corrosion and degradation to the interior of the actuator assemblies. The exact time at which leakage across the ball-valve shaft seals occurs has not been determined, however, the leakage most likely occurs during engine firings when, depending on the specification used, ball-valve cavity pressures range as high as 453 to 550 psia. This potential pressure range for the ball-valve cavities greatly exceeds the acceptance leakage test pressure of 332 psia. Since redesign and replacement of the ball-valve shaft seals is unlikely, the near term solution to prevent damage that occurs from shaft-seal leakage is to implement a routine overhaul and maintenance program for engines in the fleet. Recommended repair, verification, and possible preventative maintenance measures are discussed in the paper.

  4. Measurement of behavior of secondary sealing areas of rotary engine apex seals. ; Two-piece nonsplit and three-piece slanted horizontal split types. Apex seal no dainiji kimitsumen no kyodo no sokutei. ; Joge ittaigata nihen oyobi joge nanamebunkatsugata 3 hen seal

    Energy Technology Data Exchange (ETDEWEB)

    Matsuura, K.; Terasaki, K.; Yamane, K. (Aoyama University, Tokyo (Japan). School of Science and Engineering)

    1992-12-25

    Behavior of secondary sealing areas has been measured with two displacement sensors and an underseal pressure sensor, using an overhanging eccentric shaft-type single-rotor research engine equipped with a packaged multichannel slip ring. For the experiment, two-piece nonsplit type and three-piece slanted horizontal split type apex seals were used. The two-piece seal was tilted to the leading and trailing sides of a seal slot during its movement along the rotor housing surface and vibrated on the top end of the leading side of the slot as a fulcrum after the shift from the trailing side to the leading side of the slot. On the other hand, for the three-piece seal, its top part was tilted in all operating conditions, but its bottom part maintained effective area contact with the side of the slot under light load conditions up to medium engine speeds. The working chamber pressure was induced in the underseal in the same manner as the case with the two-piece type. 6 refs., 12 figs., 1 tab.

  5. An Improved Design of Spiral Groove Mechanical Seal%螺旋槽机械密封的改进设计

    Institute of Scientific and Technical Information of China (English)

    周剑锋; 顾伯勤; 陈晔

    2007-01-01

    The coupling effect among the flow of fluid film, the frictional heat of fluid film and the thermal deformation of sealing rings is inherent in mechanical seals. The frictional heat transfer analysis was carried out to optlmize the geometrical parameters of the sealing rings, such as the length, the inner radius and the outer radius. The geometrical parameters of spiral grooves, such as the spiral angle, the end radius, the groove depth, the ratio of the groove width to the weir width and the number of the grooves, were optimized by regarding the maximum bearing force of fluid film as the optimization objective with the coupling effect considered. The depth of spiral groove was designed to gradually increase from the end radius of spiral groove to the outer radius of end face in order to decrease the weakening effect of thermal deformation on the hydrodynamic effect of spiral grooves. The end faces of sealing rings were machined to form a divergent gap at inner radius, and a parallel gap will form to reduce the leakage rate when the thermal deformation takes place. The improved spiral groove mechanical seal possesses good heat transfer performance and sealing ability.

  6. Token Ring Project

    Directory of Open Access Journals (Sweden)

    Adela Ionescu

    2007-01-01

    Full Text Available Ring topology is a simple configuration used to connect processes that communicate among themselves. A number of network standards such as token ring, token bus, and FDDI are based on the ring connectivity. This article will develop an implementation of a ring of processes that communicate among themselves via pipe links. The processes are nodes in the ring. Each process reads from its standard input and writes in its standard output. N-1 process redirects the its standard output to a standard input of the process through a pipe. When the ring-structure is designed, the project can be extended to simulate networks or to implement algorithms for mutual exclusion

  7. Gulf ring algae

    Science.gov (United States)

    Although they rank among the tiniest of the microspcopic phytoplankton, coccolithophore algae aid oceanographers studying the Gulf Stream rings and the ring boundaries. The algal group could help to identify more precisely the boundary of the warm rings of water that spin off from the Gulf Stream and become independent pools of warm water in the colder waters along the northeastern U.S. coast.Coccolithophore populations in the Gulf Stream rings intrigue oceanographers for two reasons: The phytoplankton are subjected to an environment that changes every few days, and population explosions within one coccolithophore species seem to be associated with changes in the characteristics of ocean water, said Pat Blackwelder, an associate professor at the Nova Oceanographic Center in Dania, Fla. She is one of many studying the physics, chemistry, and biology of warm core rings. A special oceanography session on these rings was held at the recent AGU Fall Meeting/ASLO Winter Meeting.

  8. Token ring technology report

    CERN Document Server

    2013-01-01

    Please note this is a Short Discount publication. This report provides an overview of the IBM Token-Ring technology and products built by IBM and compatible vendors. It consists of two sections: 1. A summary of the design trade-offs for the IBM Token-Ring. 2. A summary of the products of the major token-ring compatible vendors broken down by adapters and components, wiring systems, testing, and new chip technology.

  9. Dusty plasma (Yukawa) rings

    CERN Document Server

    Sheridan, T E

    2010-01-01

    One-dimensional and quasi-one-dimensional strongly-coupled dusty plasma rings have been created experimentally. Longitudinal (acoustic) and transverse (optical) dispersion relations for the 1-ring were measured and found to be in very good agreement with the theory for an unbounded straight chain of particles interacting through a Yukawa (i.e., screened Coulomb or Debye-H\\"uckel) potential. These rings provide a new system in which to study one-dimensional and quasi-one-dimensional physics.

  10. Corkscrew Seals: Grey Seal (Halichoerus grypus) Infanticide and Cannibalism May Indicate the Cause of Spiral Lacerations in Seals

    Science.gov (United States)

    2016-01-01

    Large numbers of dead seals with characteristic spiral lesions have been washing ashore around the North Atlantic over the past two decades. Interactions with ship propellers and shark predation have been suggested as the likely causal mechanisms. However, new evidence points towards a more likely candidate: grey seal predation. An adult male grey seal was observed and recorded catching, killing and eating five weaned grey seal pups over a period of one week on the Isle of May, Scotland. A further 9 carcasses found in the same area exhibited similar injuries. Post mortem analysis of lesions indicated the wound characteristics were similar to each other and in 12 of the 14 carcasses analysed, were indistinguishable from carcasses previously attributed to propeller interaction. We therefore propose that most of the seal carcasses displaying spiral lacerations in the UK are caused by grey seal predation. Cases in other locations should be re-evaluated using the scoring system presented here to identify whether grey seal predation is a major cause of mortality in phocid seals. PMID:27254025

  11. Corkscrew Seals: Grey Seal (Halichoerus grypus Infanticide and Cannibalism May Indicate the Cause of Spiral Lacerations in Seals.

    Directory of Open Access Journals (Sweden)

    Andrew Brownlow

    Full Text Available Large numbers of dead seals with characteristic spiral lesions have been washing ashore around the North Atlantic over the past two decades. Interactions with ship propellers and shark predation have been suggested as the likely causal mechanisms. However, new evidence points towards a more likely candidate: grey seal predation. An adult male grey seal was observed and recorded catching, killing and eating five weaned grey seal pups over a period of one week on the Isle of May, Scotland. A further 9 carcasses found in the same area exhibited similar injuries. Post mortem analysis of lesions indicated the wound characteristics were similar to each other and in 12 of the 14 carcasses analysed, were indistinguishable from carcasses previously attributed to propeller interaction. We therefore propose that most of the seal carcasses displaying spiral lacerations in the UK are caused by grey seal predation. Cases in other locations should be re-evaluated using the scoring system presented here to identify whether grey seal predation is a major cause of mortality in phocid seals.

  12. LIFETIME PREDICTION FOR MODEL 9975 O-RINGS IN KAMS

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, E.; Skidmore, E.

    2009-11-24

    The Savannah River Site (SRS) is currently storing plutonium materials in the K-Area Materials Storage (KAMS) facility. The materials are packaged per the DOE 3013 Standard and transported and stored in KAMS in Model 9975 shipping packages, which include double containment vessels sealed with dual O-rings made of Parker Seals compound V0835-75 (based on Viton{reg_sign} GLT). The outer O-ring of each containment vessel is credited for leaktight containment per ANSI N14.5. O-ring service life depends on many factors, including the failure criterion, environmental conditions, overall design, fabrication quality and assembly practices. A preliminary life prediction model has been developed for the V0835-75 O-rings in KAMS. The conservative model is based primarily on long-term compression stress relaxation (CSR) experiments and Arrhenius accelerated-aging methodology. For model development purposes, seal lifetime is defined as a 90% loss of measurable sealing force. Thus far, CSR experiments have only reached this target level of degradation at temperatures {ge} 300 F. At lower temperatures, relaxation values are more tolerable. Using time-temperature superposition principles, the conservative model predicts a service life of approximately 20-25 years at a constant seal temperature of 175 F. This represents a maximum payload package at a constant ambient temperature of 104 F, the highest recorded in KAMS to date. This is considered a highly conservative value as such ambient temperatures are only reached on occasion and for short durations. The presence of fiberboard in the package minimizes the impact of such temperature swings, with many hours to several days required for seal temperatures to respond proportionately. At 85 F ambient, a more realistic but still conservative value, bounding seal temperatures are reduced to {approx}158 F, with an estimated seal lifetime of {approx}35-45 years. The actual service life for O-rings in a maximum wattage package likely lies

  13. On -Coherent Endomorphism Rings

    Indian Academy of Sciences (India)

    Li-Xin Mao

    2008-11-01

    A ring is called right -coherent if every principal right ideal is finitely presented. Let $M_R$ be a right -module. We study the -coherence of the endomorphism ring of $M_R$. It is shown that is a right -coherent ring if and only if every endomorphism of $M_R$ has a pseudokernel in add $M_R; S$ is a left -coherent ring if and only if every endomorphism of $M_R$ has a pseudocokernel in add $M_R$. Some applications are given.

  14. Physics of quantum rings

    Energy Technology Data Exchange (ETDEWEB)

    Fomin, Vladimir M. (ed.) [Leibniz Institute for Solid State and Materials Research, Dresden (Germany)

    2014-07-01

    Presents the new class of materials of quantum rings. Provides an elemental basis for low-cost high-performance devices promising for electronics, optoelectronics, spintronics and quantum information processing. Explains the physical properties of quantum rings to cover a gap in scientific literature. Presents the application of most advanced nanoengineering and nanocharacterization techniques. This book deals with a new class of materials, quantum rings. Innovative recent advances in experimental and theoretical physics of quantum rings are based on the most advanced state-of-the-art fabrication and characterization techniques as well as theoretical methods. The experimental efforts allow to obtain a new class of semiconductor quantum rings formed by capping self-organized quantum dots grown by molecular beam epitaxy. Novel optical and magnetic properties of quantum rings are associated with non-trivial topologies at the nanoscale. An adequate characterization of quantum rings is possible on the basis of modern characterization methods of nanostructures, such as Scanning Tunneling Microscopy. A high level of complexity is demonstrated to be needed for a dedicated theoretical model to adequately represent the specific features of quantum rings. The findings presented in this book contribute to develop low-cost high-performance electronic, spintronic, optoelectronic and information processing devices based on quantum rings.

  15. Technical Analysis and Performance Evaluation of Sliding Sleeve Seal%滑套密封技术分析与性能评估∗

    Institute of Scientific and Technical Information of China (English)

    余海燕; 雷中清; 冯强; 党伟; 周俊然; 王益山

    2015-01-01

    As an important tool of the slicing mining technology of petroleum and natural gas,sliding sleeves’ sealing performance directly affects on the slicing mining effect.Different sealing solutions used for the sliding sleeves were classi⁃fied and summarized,including the O⁃ring seal,lip seal,special seal and their different combination sealing forms.The seal⁃ing performances were evaluated for different forms of seals from five aspects,such as sealing effect,shearing resistance, wear resistance,service life and cost.By considering the five indicators synthetically,sleeve seals can choose simple star⁃rings,star⁃rings with apron,U⁃rings,double triangle rings of Tecom,and other forms of seals.Taking economy and practica⁃bility into consideration,simple O⁃rings and O⁃rings with flat apron are more applicable at slow speed and low pressure, and combination of O⁃rings and trapezoidal rings,fabric reinforced rubber combination V⁃ring seals,K⁃type seals of Tecom Manchester,T⁃rings of TeKanggelai are usually used at high pressure and large speed change.%滑套作为石油天然气分层开采技术的重要工具,其密封性能直接影响着施工的效果。对用于滑套的不同密封方案进行总结分类,包括O形圈密封、唇形密封、特殊型密封及其不同的组合密封形式;从密封效果、抗剪切性、耐磨性、使用寿命、成本5项指标对各类密封进行性能评估。综合考虑5项指标,滑套密封可选用简单星形密封圈、星形密封圈加挡圈、 U型密封圈、特康双三角密封圈等密封形式;而从经济实用方面来考虑,低压且速度不高时,可使用简单O形圈、 O形密封圈加平挡圈;压力较高且速度变化较大时,可使用O形圈和梯形环的组合、 V形夹织物橡胶组合密封圈、 K型特康斯特密封圈、 T型特康格来圈。

  16. Spontaneous Sealing of a Type Ia Endoleak after Ovation Stent Graft Implantation in a Patient with On-Label Aortic Neck Anatomy.

    Science.gov (United States)

    Pranteda, Chiara; Sirignano, Pasqualino; Capoccia, Laura; Mansour, Wassim; Montelione, Nunzio; Speziale, Francesco

    2016-07-01

    We report a case of an early type Ia endoleak after endovascular aneurysm repair (EVAR) of an abdominal aortic aneurysm by Ovation Stent Graft implantation and spontaneously resolved without further reintervention. The patient presents a conical aortic neck, but EVAR was performed within the instruction for use proposed by manufactory. At completion angiography, a low-flow type Ia endoleak was present and left untreated. Computed tomographic angiography performed on the third postoperative day showed infolding of the 2 sealing rings. The patient was dismissed without further treatment. At 3-month follow-up, the leak appeared spontaneously sealed with partial expansion of the 2 rings.

  17. Phosphorus recycling in sediments of the Central Baltic Sea

    Directory of Open Access Journals (Sweden)

    L. Viktorsson

    2012-11-01

    Full Text Available Benthic fluxes of dissolved inorganic phosphorus (DIP were measured in situ in the Eastern Gotland Basin (EGB, Central Baltic Sea, using benthic landers. A total of 40 flux measurements on 13 stations at water depths ranging from 30–210 m and under different oxygen regimes were carried out on three cruises during three consecutive years (2008–2010 in August–September. Our study is the first to report in situ DIP fluxes in the Baltic Proper, and it provides the most comprehensive data set of benthic DIP fluxes in the Baltic Proper existing to date. DIP fluxes increased with increasing water depth and with decreasing bottom water oxygen concentration. Average fluxes were calculated for oxic bottom water conditions (−0.003 ± 0.040 mmol m−2 d−1, hypoxic conditions (0.027 ± 0.067 mmol m−2 d−1 and anoxic conditions (0.376 ± 0.214 mmol m−2 d−1. The mean flux on anoxic bottoms was ca. 5–10 times higher than previous estimates based on ex situ measurements, but agreed well with previous flux estimations from changes in the basin water DIP pool. The DIP flux was positively correlated with the organic carbon inventory of sediment and the benthic flux of dissolved inorganic carbon (DIC on anoxic stations, but these variables were uncorrelated on oxic stations. The positive correlation between DIP and DIC fluxes suggests that the benthic DIP flux on anoxic bottoms in the Baltic Proper is mainly controlled by rates of deposition and degradation of organic matter. The flux from anoxic sediment was very P rich in relation to both C and N, and the average C:P ratio in fluxes on anoxic accumulation bottoms was 69 ± 15, which is well below the Redfield C:P ratio of 106:1. On oxic stations, however, the C:P flux ratio was much higher than the Redfield ratio, consistent with well-known P retention mechanisms associated with iron and bacteria in oxidized sediment. Using a

  18. Ring Around a Galaxy

    Science.gov (United States)

    1999-01-01

    Space Telescope Science Institute astronomers are giving the public chances to decide where to aim NASA's Hubble Space Telescope. Guided by 8,000 Internet voters, Hubble has already been used to take a close-up, multi-color picture of the most popular object from a list of candidates, the extraordinary 'polar-ring' galaxy NGC 4650A. Located about 130 million light-years away, NGC 4650A is one of only 100 known polar-ring galaxies. Their unusual disk-ring structure is not yet understood fully. One possibility is that polar rings are the remnants of colossal collisions between two galaxies sometime in the distant past, probably at least 1 billion years ago. What is left of one galaxy has become the rotating inner disk of old red stars in the center. Meanwhile, another smaller galaxy which ventured too close was probably severely damaged or destroyed. The bright bluish clumps, which are especially prominent in the outer parts of the ring, are regions containing luminous young stars, examples of stellar rebirth from the remnants of an ancient galactic disaster. The polar ring appears to be highly distorted. No regular spiral pattern stands out in the main part of the ring, and the presence of young stars below the main ring on one side and above on the other shows that the ring is warped and does not lie in one plane. Determining the typical ages of the stars in the polar ring is an initial goal of our Polar Ring Science Team that can provide a clue to the evolution of this unusual galaxy. The HST exposures were acquired by the Hubble Heritage Team, consisting of Keith Noll, Howard Bond, Carol Christian, Jayanne English, Lisa Frattare, Forrest Hamilton, Anne Kinney and Zolt Levay, and guest collaborators Jay Gallagher (University of Wisconsin-Madison), Lynn Matthews (National Radio Astronomy Observatory-Charlottesville), and Linda Sparke (University of Wisconsin-Madison).

  19. Space Environment Effects on Silicone Seal Materials

    Science.gov (United States)

    deGroh, Henry C., III; Daniels, Christopher C.; Dever, Joyce A.; Miller, Sharon K.; Waters, Deborah L.; Finkbeiner, Joshua R.; Dunlap, Patrick H.; Steinetz, Bruce M.

    2010-01-01

    A docking system is being developed by the NASA to support future space missions. It is expected to use redundant elastomer seals to help contain cabin air during dockings between two spacecraft. The sealing surfaces are exposed to the space environment when vehicles are not docked. In space, the seals will be exposed to temperatures between 125 to -75 C, vacuum, atomic oxygen, particle and ultraviolet radiation, and micrometeoroid and orbital debris (MMOD). Silicone rubber is the only class of space flight-qualified elastomeric seal material that functions across the expected temperature range. NASA Glenn has tested three silicone elastomers for such seal applications: two provided by Parker (S0899-50 and S0383-70) and one from Esterline (ELA-SA-401). The effects of atomic oxygen (AO), UV and electron particle radiation, and vacuum on the properties of these three elastomers were examined. Critical seal properties such as leakage, adhesion, and compression set were measured before and after simulated space exposures. The S0899-50 silicone was determined to be inadequate for extended space seal applications due to high adhesion and intolerance to UV, but both S0383-70 and ELA-SA-401 seals were adequate.

  20. Space Environment's Effects on Seal Materials

    Science.gov (United States)

    deGroh, Henry C., III; Daniels, Christopher C.; Dunlap, Patrick; Miller, Sharon; Dever, Joyce; Waters, Deborah; Steinetz, Bruce M.

    2007-01-01

    A Low Impact Docking System (LIDS) is being developed by the NASA Johnson Space Center to support future missions of the Crew Exploration Vehicle (CEV). The LIDS is androgynous, such that each system half is identical, thus any two vehicles or modules with LIDS can be coupled. Since each system half is a replica, the main interface seals must seal against each other instead of a conventional flat metal surface. These sealing surfaces are also expected to be exposed to the space environment when vehicles are not docked. The NASA Glenn Research Center (NASA GRC) is supporting this project by developing the main interface seals for the LIDS and determining the durability of candidate seal materials in the space environment. In space, the seals will be exposed to temperatures of between 50 to 50 C, vacuum, atomic oxygen, particle and ultraviolet radiation, and micrometeoroid and orbital debris (MMOD). NASA GRC is presently engaged in determining the effects of these environments on our candidate elastomers. Since silicone rubber is the only class of seal elastomer that functions across the expected temperature range, NASA GRC is focusing on three silicone elastomers: two provided by Parker Hannifin (S0-899-50 and S0-383-70) and one from Esterline Kirkhill (ELA-SA-401). Our results from compression set, elastomer to elastomer adhesion, and seal leakage tests before and after various simulated space exposures will be presented.

  1. 19 CFR 101.7 - Customs seal.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Customs seal. 101.7 Section 101.7 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY GENERAL PROVISIONS § 101.7 Customs seal. (a) Design. According to the design furnished by the...

  2. Earlier pupping in harbour seals, Phoca vitulina

    NARCIS (Netherlands)

    Reijnders, P.J.H.; Brasseur, S.M.J.M.; Meesters, H.W.G.

    2010-01-01

    The annual reproductive cycle of most seal species is characterized by a tight synchrony of births. Typically, timing of birth shows little inter-annual variation. Here, however we show that harbour seals Phoca vitulina from the Wadden Sea (southeast North Sea) have shortened their yearly cycle, mov

  3. Lead mobilization during tectonic reactivation of the western Baltic Shield

    Energy Technology Data Exchange (ETDEWEB)

    Romer, R.L. (Rice Univ., Houston, TX (United States) Luleaa Univ. (Sweden)); Wright, J.E. (Rice Univ., Houston, TX (United States))

    1993-06-01

    Lead isotope data from sulfide deposits of the western part of the Baltic Shield define mixing lines in the [sup 206]Pb/[sup 204]Pb-[sup 207]Pb/[sup 204]Pb diagram. Lead from two types of sulfide deposits have been investigated: (1) Exhalative and volcanogenic deposits that are syngenetic with their host rocks; and (2) vein deposits. The syngenetic deposits locally show a very wide range of lead isotopic compositions that reflect a variable addition of highly radiogenic lead, while the vein deposits, although they have radiogenic lead isotopic compositions, exhibit only limited isotopic variations. In different provinces of the shield, both types of deposits fall on the same lead mixing array. The slope of the lead mixing lines varies as a function of the age of basement rocks and the age of the tectonic event which produced the lead mobilization and therefore relates the source rock age with the age of lead mobilization. Calculated mixing ages fall into several short time periods that correspond either to orogenic events or to major phases of continental rifting. The orogenic events are the ca 360--430 Ma Caledonian, ca 900--1100 Ma Sveconorwegian, and the ca 1800--1900 Ma Svecofennian orogenic cycles. The rifting events correspond to the formation of the ca 280 Ma Oslo rift and the Ordovician (ca 450 Ma) graben system in the area of the present Gulf of Bothnia. Each mixing age indicates that lead was mobilized, probably as a consequence of mild thermal disturbances, and that the crust was permeable to lead migration. The data show that the geographic distribution of sulfide deposits with highly radiogenic lead isotopic compositions coincides with old graben systems, orogenic belts, and orogenic forelands on the Baltic Shield. The ages of vein deposits and their geographic distribution demonstrate multiple tectonic reactivation of the interior of the Baltic Shield in response to orogenic events at its margin. 68 refs., 6 refs., 4 tabs.

  4. Sea Salt Source Function over the Baltic Sea

    Science.gov (United States)

    Petelski, Tomasz; Makuch, Przemyslaw; Markuszewski, Piotr; Jankowski, Andrzej; Zieliński, Tymon

    2013-04-01

    Studies of production and transport of aerosol over the sea are very important for many areas of knowledge. Marine aerosol emitted from the sea surface helps to clean the boundary layer from other aerosol particles. The emitted droplets do not dry out in the highly humid surface layer air and because of their sizes most of them are deposited quickly at the sea surface. Therefore, marine aerosol has many features of rain i.e. the deposition in the marine boundary layer in high wind events is controlled not only by the "dry" processes but also by the "wet" scavenging. While many cruises conducted on board S/Y Oceania, we collected many data which were used to calculate sea salt source function over the Baltic Sea. Our cruises held between 2009 and 2012. Measurements were carried out using gradient method. For this method we used Laser Particle Counter (PMS model CSASP-100_HV) placed on one oft the mast of S/Y Oceania. Measurements were performed on five different levels around sea level: 8, 11, 14, 17 and 20 meters. Based on the averaged vertical concentration, profiles were calculated, using Monin-Obuchow theory, vertical sea spray fluxes in the near water layer. Based on fluxes calculated from vertical concentration profiles was calculated sea salt source function over the Baltic Sea. This function gives emission for different particle size, depending on environmental parameters. Emission of sea spray depends of the size of energy lost by the wind waves in process of collapse. Acknowledgements: The support for this study was provided by the project Satellite Monitoring of the Baltic Sea Environment - SatBałtyk founded by European Union through European Regional Development Fund contract No. POIG 01.01.02-22-011/09.

  5. Ring-opening of cyclic ethers with carbon–carbon bond formation by Grignard reagents

    DEFF Research Database (Denmark)

    Christensen, Stig Holden; Holm, Torkil; Madsen, Robert

    2014-01-01

    The ring-opening of cyclic ethers with concomitant C–C bond formation was studied with a number of Grignard reagents. The transformation was performed in a sealed vial by heating to ∼160 °C in an aluminum block or at 180 °C in a microwave oven. Good yields of the product alcohols were obtained wi...

  6. Active Infrared Thermography for Seal Contamination Detection in Heat-Sealed Food Packaging

    Directory of Open Access Journals (Sweden)

    Karlien D’huys

    2016-11-01

    Full Text Available Packaging protects food products from environmental influences, assuring quality and safety throughout shelf life if properly performed. Packaging quality depends on the quality of the packaging material and of the closure or seal. A common problem possibly jeopardizing seal quality is the presence of seal contamination, which can cause a decreased seal strength, an increased packaging failure risk and leak formation. Therefore, early detection and removal of seal contaminated packages from the production chain is crucial. In this work, a pulsed-type active thermography method using the heated seal bars as an excitation source was studied for detecting seal contamination. Thermal image sequences of contaminated seals were recorded shortly after sealing. The detection performances of six thermal image processing methods, based on a single frame, a fit of the cooling profiles, thermal signal reconstruction, pulsed phase thermography, principal component thermography and a matched filter, were compared. High resolution digital images served as a reference to quantify seal contamination, and processed thermal images were mapped to these references. The lowest detection limit (equivalent diameter 0.60 mm was obtained for the method based on a fit of the cooling profiles. Moreover, the detection performance of this method did not depend strongly on the time after sealing at which recording of the thermal images was started, making it a robust and generally applicable method.

  7. Grey seal (Halichoerus grypus) predation on harbour seals (Phoca vitulina) on the island of Helgoland, Germany

    Science.gov (United States)

    van Neer, Abbo; Jensen, Lasse Fast; Siebert, Ursula

    2015-03-01

    The prey spectrum of grey seals has to date been described as largely consisting of different fish, cephalopod and shrimp species. On the German island of Helgoland Düne, where harbour seals (Phoca vitulina) and grey seals (Halichoerus grypus) co-occur, a young male grey seal was observed in 2013 and again in 2014 preying upon young harbour seals. A harbour seal carcass with severe traumatic lesions was retrieved and post-mortem examinations were performed. In the following weeks several carcasses showing similar lesions were found. Sightings of grey seals assumed to be preying on harbour porpoises have increased around the North Sea. Increased competition as well as individualised behaviour could explain the increased number of observations, but former cases of abnormal lesions of marine mammals attributed to for example predation by sharks or mechanical processes should be revisited with regard to the emerging knowledge.

  8. Ice-ocean-ecosystem operational model of the Baltic Sea

    Science.gov (United States)

    Janecki, M.; Dzierzbicka-Glowacka, L.; Jakacki, J.; Nowicki, A.

    2012-04-01

    3D-CEMBS is a fully coupled model adopted for the Baltic Sea and have been developed within the grant, wchich is supported by the Polish State Committee of Scientific Reasearch. The model is based on CESM1.0 (Community Earth System Model), in our configuration it consists of two active components (ocean and ice) driven by central coupler (CPL7). Ocean (POP version 2.1) and ice models (CICE model, version 4.0) are forced by atmospheric and land data models. Atmospheric data sets are provided by ICM-UM model from University of Warsaw. Additionally land model provides runoff of the Baltic Sea (currently 78 rivers). Ecosystem model is based on an intermediate complexity marine ecosystem model for the global domain (J.K. Moore et. al., 2002) and consists of 11 main components: zooplankton, small phytoplankton, diatoms, cyanobacteria, two detrital classes, dissolved oxygen and the nutrients nitrate, ammonium, phosphate and silicate. The model is configured at two horizontal resolutions, approximately 9km and 2km (1/12° and 1/48° respectively). The model bathymetry is represented as 21 vertical levels and the thickness of the first four layers were chosen to be five metres. 3D-CEMBS model grid is based on stereographic coordinates, but equator of these coordinates is in the centre of the Baltic Sea (rotated stereographic coordinates) and we can assume that shape of the cells are square and they are identical. Currently model works in a operational state. The model creates 48-hour forecasts every 6 hours (or when new atmospheric dataset is available). Prognostic variables such as temperature, salinity, ice cover, currents, sea surface height and phytoplankton concentration are presented online on a the website and are available for registered users. Also time series for any location are accessible. This work was carried out in support of grant No NN305 111636 and No NN306 353239 - the Polish state Committee of Scientific Research. The partial support for this study was

  9. Single and multispecies reference points for Baltic fish stocks

    DEFF Research Database (Denmark)

    Gislason, Henrik

    1999-01-01

    reference points. Management advice based on biomass reference points will also differ. In the single species situation the combinations of cod and pelagic fishing effort for which the equilibrium spawning- stock biomass of the three species is above the biomass reference points forms a rectangular area....... Multispecies predictions suggest that the cod stock in the Baltic should be reduced to a very low level of biomass in order to benefit from the higher productivity of herring and sprat, its major prey. Such a result stresses the need for incorporating socio-economic considerations in the definition of target...

  10. Evidence concerning oxidation as a surface reaction in Baltic amber

    DEFF Research Database (Denmark)

    Shashoua, Yvonne

    2012-01-01

    The aim of this study was to provide evidence about oxidation as a surface reaction during degradation of Baltic amber. A clear understanding of the amber-oxygen interaction modalities is essential to develop conservation techniques for museum collections of amber objects. Pellet-shaped samples......, obtained from pressed amber powder, were subjected to accelerated thermal ageing. Cross-sections of the pellets were analyzed by infrared micro-spectroscopy, in order to identify and quantify changes in chemical properties. The experimental results showed strong oxidation exclusively at the exterior part...

  11. Denitrification in the water column of the central Baltic Sea

    DEFF Research Database (Denmark)

    Dalsgaard, Tage; De Brabandere, Loreto; Hall, Per

    2013-01-01

    Removal of fixed nitrogen in the water column of the eastern Gotland Basin, central Baltic Sea, was studied during two cruises in September 2008 and August 2010. The water column was stratified with anoxic sulfidic bottom water meeting oxic nitrate containing water at the oxic–anoxic interface...... was in some situations driven by organic matter alone. Nitrous oxide (N2O) became an increasingly important product of denitrification with increasing sulfide concentration and was >80% of the total N gas formation at 10 μM sulfide. The potential rates of denitrification measured in incubations at elevated...

  12. Fish production and climate: Sprat in the Baltic Sea

    DEFF Research Database (Denmark)

    MacKenzie, Brian; Köster, Fritz

    2004-01-01

    Processes controlling the production of new fish (recruitment) are poorly understood and therefore challenge population ecologists and resource managers. Sprat in the Baltic Sea is no exception: recruitment varies widely between years and is virtually independent of the biomass of mature sprat...... of data that recruitment depends on temperature conditions during the months when sprat gonads, eggs, and larvae are developing. We also show that recruitment can be predicted before adults spawn (and fully 15 months earlier than using present technology) by using linkages between recruitment, large...

  13. The Transformation of Energy Risk in the Baltic States

    Directory of Open Access Journals (Sweden)

    Leonavičius Vylius

    2014-06-01

    Full Text Available The aim of the article is to reveal the process of energy risk transformation, which creates concrete hazards for citizens of the Baltic States. The article analyzes two sides of the same problem - district heating (DH and the renovation of multi-apartment houses. The article will show that the transformation of energy risk is affected by the legacy of a specific constellation of technological, economic and social elements of Soviet infrastructure that appears in a specific and particularly precarious shape under conditions of liberal market capitalism as regards energy security.

  14. Eastern Baltic cod recruitment revisited—dynamics and impacting factors

    DEFF Research Database (Denmark)

    Köster, Fritz; Huwer, Bastian; Hinrichsen, Hans-Harald

    2016-01-01

    and casting doubts about the magnitude of the recent increase in recruitment. Earlier studies identified main factors impacting on cod reproductive success to be related to the loss of two out of three spawning areas in the 1980s caused by lack of major Baltic inflows with a concurrent reduction in salinity...... and oxygen. Other important factors include prey availability for first-feeding larvae, egg predation by sprat and herring and cannibalism on juveniles, all in one way or the other related to the prevailing hydrographic conditions. These factors cannot explain increased reproductive success in the last...

  15. Early Holocene lake ecosystem development in the southern Baltic lowlands

    Science.gov (United States)

    Słowiński, Michał; Ott, Florian; Kramkowski, Mateusz; Noryśkiewicz, Agnieszka M.; Zawiska, Izabela; Dräger, Nadine; Theuerkauf, Martin; Hass, Christoph; Obremska, Milena; Błaszkiewicz, Mirosław; Kordowski, Jarosław; Tjallingii, Rik; Rzodkiewicz, Monika; Schwab, Markus; Brauer, Achim

    2016-04-01

    The first millennia of the Holocene are characterized by gradual and rapid environmental changes following the warming at the beginning of the Holocene superimposed by short-term climatic instability. Landscape evolution during this period occurred at different time scales due to specific response times of landscape compartments like vegetation succession, soil formation and permafrost thawing. As a consequence, a spatiotemporally heterogeneous pattern of changes occurred particularly in regions close to the margins of the continental ice sheets like the Baltic region. Regional atmospheric circulation patterns were affected by cold catabatic winds from the remains of the Fennoscandian ice sheet. The ongoing deglaciation further influenced the regional climate through meltwater release and related changes in the North Atlantic thermohaline circulation. Both effects declined with the progressive ice sheet melt down. Additionally, the land-sea distribution in the North Sea changed drastically during the final melting phase of the glacial ice sheets. The Baltic Sea development is even more complex due to the strong glacio-isostatic adjustments effects that resulted in open and closed water stages affecting the entire Baltic realm. Consequently, the early Holocene interval of sediment records from the southern Baltic lowlands are not considered as straightforward palaeoclimate archives but need to be interpreted in a broader context. We present five partly varved lake records from northern Poland all including an intriguing highly organic-rich interval interrupting biochemical calcite precipitation at about the same time between 10.5 and 10.2 cal kyr BP. These sediment records have been correlated by independent age models based on varve counting, AMS 14C dating, biostratigraphy and tephrochronology. We present multi-proxy records of early Holocene sediments and our preliminary interpretation suggests hydrological processes as the main reason for the intriguing shifts

  16. SAR-based Wind Resource Statistics in the Baltic Sea

    DEFF Research Database (Denmark)

    Hasager, Charlotte Bay; Badger, Merete; Pena Diaz, Alfredo;

    2011-01-01

    Ocean winds in the Baltic Sea are expected to power many wind farms in the coming years. This study examines satellite Synthetic Aperture Radar (SAR) images from Envisat ASAR for mapping wind resources with high spatial resolution. Around 900 collocated pairs of wind speed from SAR wind maps...... deviation of 20.11° and R2 of 0.950. The scale and shape parameters, A and k, respectively, from the Weibull probability density function are compared at only one available mast and the results deviate ~2% for A but ~16% for k. Maps of A and k, and wind power density based on more than 1000 satellite images...

  17. Measurements of Scattering Function of sea water in Southern Baltic

    Science.gov (United States)

    Freda, W.; Król1, T.; Martynov, O. V.; Shybanov, E. B.; Hapter, R.

    2007-05-01

    The Volume Scattering Functions (VSF) were measured in Southern Baltic area. The instrument used to this aim allow to measure in full range of angles and for four wavelengths. Obtained characteristics create the set of data which is need to solve the radiative transfer equation. Measured functions were compared with Petzold Average-Particle Phase Function. Spectral variations of measured scattering coefficients and backscattering coefficients are presented. Furthermore the instability of measured scattering ratios is discussed in this paper. Such instability have not been mentioned in the literature before.

  18. Natural Increase in the Baltic South and South-West

    Directory of Open Access Journals (Sweden)

    Michalski T.

    2014-05-01

    Full Text Available This article analyses the natural population increase (decrease in the postcommunist part of Baltic Europe (the federated state of Mecklenburg-Western Pomerania, West Pomeranian, Pomeranian, and Warmian-Masurian Voivodeships, Lithuania, Latvia, Estonia, the Kaliningrad and Leningrad region, and the federal city of Saint Petersburg in 2002—2011. The study uses standard methods of demographic analysis, the data provided by national statistical services and Eurostat. All regions analysed are characterised by a low stationary phase of the demographic transition model (DTM. The situation proves to be unfavourable in the Polish regions under consideration and highly unfavourable in the remaining area.

  19. [Methods for sealing of corneal perforations].

    Science.gov (United States)

    Samoilă, O; Totu, Lăcrămioara; Călugăru, M

    2012-01-01

    A variety of corneal pathology can lead to corneal ulcers and perforations. A deep corneal ulcer may need surgical treatment to allow good volume restoration and reepithelisation. Corneal perforation must be sealed and when the perforation is large, the task of repairing the defect can be underwhelming. The elegant solution is the corneal transplant, but this is not always readily available, especially in undeveloped countries. We present here two cases with different solutions to seal the perforated cornea: the first one has a large peripheral defect and it is successfully sealed with scleral patch and the second one is central with small perforation and is successfully sealed with multilayered amniotic membrane. Both cases are followed for over 12 months and demonstrate good corneal restoration (both on clinical examination and corneal topography). Sclera and amniotic membrane can be used to seal corneal defects when corneal transplant is not readily available.

  20. Film riding seal assembly for turbomachinery

    Energy Technology Data Exchange (ETDEWEB)

    Bidkar, Rahul Anil; Giametta, Andrew Paul; Gibson, Nathan Evan McCurdy; Cleveland, Nicolas Joseph

    2016-06-07

    An aerodynamic seal assembly for a rotary machine includes multiple sealing segments disposed circumferentially intermediate to a stationary housing and a rotor. Each of the segments includes a shoe plate with a forward load-bearing section and an aft load-bearing section configured to generate an aerodynamic force between the shoe plate and the rotor. The shoe plate includes at least one labyrinth teeth facing the rotor and positioned between the forward load-bearing section and the aft load-bearing section. The sealing segment also includes at least one spring connected to a pedestal located about midway of an axial length of the shoe plate and to a stator interface element. Further, the sealing segment includes a rigid segmented secondary seal attached to the stator interface element at one first end and in contact with the pedestal of the shoe plate at one second end.

  1. A reliable sealing method for microbatteries

    Science.gov (United States)

    Wang, Yuxing; Cartmell, Samuel; Li, Qiuyan; Xiao, Jie; Li, Huidong; Deng, Zhiqun Daniel; Zhang, Ji-Guang

    2017-02-01

    As electronic devices continue to become smaller, their energy sources (i.e., batteries) also need to be smaller. Typically, energy densities of batteries decrease as the battery size decreases due to the relative increase of parasitic weight such as packaging materials. In addition, the sealing methods in conventional batteries are difficult to apply to microbatteries. In this work, we developed a facile sealing method for microbatteries. The method employs a dual-sealing concept: a first rubber barrier temporally confines the organic electrolytes and a second adhesive barrier forms a hermetic seal with the battery case. With this innovative sealing approach, excellent shelf life and operation life of the batteries have been demonstrated. A minimal amount of packing materials is employed resulting in high energy densities.

  2. Illustration of Saturn's Rings

    Science.gov (United States)

    2001-01-01

    This illustration shows a close-up of Saturn's rings. These rings are thought to have formed from material that was unable to form into a Moon because of tidal forces from Saturn, or from a Moon that was broken up by Saturn's tidal forces.

  3. Birth Control Ring

    Science.gov (United States)

    ... 5 of her menstrual cycle. It remains in place for 3 weeks in a row. At the end of the third week, on the same day of the week ... birth control until the ring has been in place for 7 days. If the ring is out for more than 3 hours during your third week wearing it, call your doctor to see ...

  4. Revocable Ring Signature

    Institute of Scientific and Technical Information of China (English)

    Dennis Y. W. Liu; Joseph K. Liu; Yi Mu; Willy Susilo; Duncan S. Wong

    2007-01-01

    Group signature allows the anonymity of a real signer in a group to be revoked by a trusted party called group manager. It also gives the group manager the absolute power of controlling the formation of the group. Ring signature, on the other hand, does not allow anyone to revoke the signer anonymity, while allowing the real signer to forma group (also known as a ring) arbitrarily without being controlled by any other party. In this paper, we propose a new variant for ring signature, called Revocable Ring Signature. The signature allows a real signer to form a ring arbitrarily while allowing a set of authorities to revoke the anonymity of the real signer. This new variant inherits the desirable properties from both group signature and ring signature in such a way that the real signer will be responsible for what it has signed as the anonymity is revocable by authorities while the real signer still has the freedom on ring formation. We provide a formal security model for revocable ring signature and propose an efficient construction which is proven secure under our security model.

  5. EBT ring physics

    Energy Technology Data Exchange (ETDEWEB)

    Uckan, N.A. (ed.)

    1980-04-01

    This workshop attempted to evaluate the status of the current experimental and theoretical understanding of hot electron ring properties. The dominant physical processes that influence ring formation, scaling, and their optimal behavior are also studied. Separate abstracts were prepared for each of the 27 included papers. (MOW)

  6. The Fermilab recycler ring

    Energy Technology Data Exchange (ETDEWEB)

    Martin Hu

    2001-07-24

    The Fermilab Recycler is a permanent magnet storage ring for the accumulation of antiprotons from the Antiproton Source, and the recovery and cooling of the antiprotons remaining at the end of a Tevatron store. It is an integral part of the Fermilab III luminosity upgrade. The following paper describes the design features, operational and commissioning status of the Recycler Ring.

  7. Steroidal contraceptive vaginal rings.

    Science.gov (United States)

    Sarkar, N N

    2003-06-01

    The development of steroid-releasing vaginal rings over the past three decades is reviewed to illustrate the role of this device as an effective hormonal contraceptive for women. Vaginal rings are made of polysiloxane rubber or ethylene-vinyl-acetate copolymer with an outer diameter of 54-60 mm and a cross-sectional diameter of 4-9.5 mm and contain progestogen only or a combination of progestogen and oestrogen. The soft flexible combined ring is inserted in the vagina for three weeks and removed for seven days to allow withdrawal bleeding. Progesterone/progestogen-only rings are kept in for varying periods and replaced without a ring-free period. Rings are in various stages of research and development but a few, such as NuvaRing, have reached the market in some countries. Women find this method easy to use, effective, well tolerated and acceptable with no serious side-effects. Though the contraceptive efficacy of these vaginal rings is high, acceptability is yet to be established.

  8. Algorithms for finite rings

    NARCIS (Netherlands)

    Ciocanea Teodorescu I.,

    2016-01-01

    In this thesis we are interested in describing algorithms that answer questions arising in ring and module theory. Our focus is on deterministic polynomial-time algorithms and rings and modules that are finite. The first main result of this thesis is a solution to the module isomorphism problem in

  9. Planetary rings - Theory

    Science.gov (United States)

    Borderies, Nicole

    1989-01-01

    Theoretical models of planetary-ring dynamics are examined in a brief analytical review. The mathematical description of streamlines and streamline interactions is outlined; the redistribution of angular momentum due to collisions between particles is explained; and problems in the modeling of broad, narrow, and arc rings are discussed.

  10. CHARACTERISTCS OF FLUID FILM IN OPTIMIZED SPIRAL GROOVE MECHANICAL SEAL

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In order to investigate the sealing performance variation resulted from the thermal deformation of the end faces, the equations to calculate the fluid film pressure distribution, the bearing force and the leakage rate are derived, for the fluid film both in parallel gap and in wedgy gap. The geometrical parameters of the sealing members are optimized by means of heat transfer analysis and complex method. The analysis results indicate that the shallow spiral grooves can generate hydrodynamic pressure while the rotating ring rotates and the bearing force of the fluid film in spiral groove end faces is much larger than that in the flat end faces. The deformation increases the bearing force of the fluid film in flat end faces, but it decreases the hydrodynamic pressure of the fluid film in spiral groove end faces. The gap dimensions which determine the characteristics of the fluid film is obtained by coupling analysis of the frictional heat and the thermal deformation in consideration of the equilibrium condition of the bearing force and the closing force. For different gap dimensions, the relationship between the closing force and the leakage rate is also investigated, based on which the leakage rate can be controlled by adjusting the closing force.

  11. Does the seal licensing system in Scotland have a negative impact on seal welfare?

    Directory of Open Access Journals (Sweden)

    Laetitia Nunny

    2016-08-01

    Full Text Available This study examined the licensing system that permits seal shooting in Scotland, which was established under Part 6 Conservation of Seals of the Marine (Scotland Act 2010. Four approaches were used: data were collated and analyzed from both the Scottish Government and Scottish Marine Animal Stranding Scheme; a survey was sent to current license holders and informal interviews were conducted with key stakeholder types. Between February 2011 and the end of October 2015, 1229 gray seals and 275 common seals were reported shot under license to the Scottish Government. The numbers of seals reported as shot has reduced year-on-year since the licensing system was put in place. While some license holders, notably fish farms, were using some non-lethal forms of deterrent to reduce seal-related damage, these were often used alongside seal shooting. Of the seals reported as shot to the Scottish Government, only a small percentage were also reported to the Scottish Marine Animal Stranding Scheme, despite this being a licensing requirement. Only 2.3% of the shot gray seals and 4.5% of the shot common seals were necropsied. There is evidence from these necropsies that some seals had not died instantly or had not been shot in the manner recommended by the Scottish Seal Management Code of Practice. These preliminary results show that more carcasses need to be recovered and necropsied if the welfare implications of current seal shooting practice are to be properly assessed. The current legislation does not specify closed seasons to protect breeding seals and thirty-five per cent of necropsied seals were pregnant gray seals. Seals have also been shot during their lactation periods when pups are dependent on their mothers. This raises significant welfare concerns. The re-introduction of closed seasons specific to each species of seal is recommended along with greater effort to deploy non-lethal methods. Independent assessment of the number of seals being killed

  12. Jupiter's Rings: Sharpest View

    Science.gov (United States)

    2007-01-01

    The New Horizons spacecraft took the best images of Jupiter's charcoal-black rings as it approached and then looked back at Jupiter. The top image was taken on approach, showing three well-defined lanes of gravel- to boulder-sized material composing the bulk of the rings, as well as lesser amounts of material between the rings. New Horizons snapped the lower image after it had passed Jupiter on February 28, 2007, and looked back in a direction toward the sun. The image is sharply focused, though it appears fuzzy due to the cloud of dust-sized particles enveloping the rings. The dust is brightly illuminated in the same way the dust on a dirty windshield lights up when you drive toward a 'low' sun. The narrow rings are confined in their orbits by small 'shepherding' moons.

  13. Atmospheric forcing of decadal Baltic Sea level variability in the last 200 years. A statistical analysis

    Energy Technology Data Exchange (ETDEWEB)

    Huenicke, B. [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Inst. fuer Kuestenforschung

    2008-11-06

    This study aims at the estimation of the impact of different atmospheric factors on the past sealevel variations (up to 200 years) in the Baltic Sea by statistically analysing the relationship between Baltic Sea level records and observational and proxy-based reconstructed climatic data sets. The focus lies on the identification and possible quantification of the contribution of sealevel pressure (wind), air-temperature and precipitation to the low-frequency (decadal and multi-decadal) variability of Baltic Sea level. It is known that the wind forcing is the main factor explaining average Baltic Sea level variability at inter-annual to decadal timescales, especially in wintertime. In this thesis it is statistically estimated to what extent other regional climate factors contribute to the spatially heterogeneous Baltic Sea level variations around the isostatic trend at multi-decadal timescales. Although the statistical analysis cannot be completely conclusive, as the potential climate drivers are all statistically interrelated to some degree, the results indicate that precipitation should be taken into account as an explanatory variable for sea-level variations. On the one hand it has been detected that the amplitude of the annual cycle of Baltic Sea level has increased throughout the 20th century and precipitation seems to be the only factor among those analysed (wind through SLP field, barometric effect, temperature and precipitation) that can account for this evolution. On the other hand, precipitation increases the ability to hindcast inter-annual variations of sea level in some regions and seasons, especially in the Southern Baltic in summertime. The mechanism by which precipitation exerts its influence on Baltic Sea level is not ascertained in this statistical analysis due to the lack of long salinity time series. This result, however, represents a working hypothesis that can be confirmed or disproved by long simulations of the Baltic Sea system - ocean

  14. SatBałtyk - a project for satellite remote sensing of the Baltic ecosystem

    Science.gov (United States)

    Wozniak, B.; Bradtke, K.; Darecki, M.; Dera, J.; Dudzinska-Nowak, J.; Dzierzbicka-Glowacka, L.; Ficek, D.; Furmanczyk, K.; Kowalewski, M.; Krezel, A.; Majchrowski, R.; Ostrowska, M.; Paszkuta, M.; Ston-Egiert, J.; Stramska, M.; Zapadka, T.

    2012-04-01

    The main aim of the five-year SatBałtyk (2010-2014) research project (Satellite Monitoring of the Baltic Sea Environment) is to prepare the technical infrastructure and set in motion operational procedures for the satellite monitoring of the Baltic environment. This system is to characterize on a routine basis the structural and functional properties of this sea on the basis of data supplied by the relevant satellites. The characterization and large-scale dissemination of the following properties of the Baltic is anticipated: the solar radiation influx to the sea's waters in various spectral intervals, energy balances of the short- and long-wave radiation at the Baltic Sea surface and in the upper layers of the atmosphere over the Baltic, sea surface temperature distribution, dynamic states of the water surface, concentrations of chlorophyll a and other phytoplankton pigments in the Baltic water, distributions of algal blooms, the occurrence of upwelling events, and the characteristics of primary organic matter production and photosynthetically released oxygen in the water. It is also intended to develop and, where feasible, to implement satellite techniques for detecting slicks of petroleum derivatives and other compounds, evaluating the state of the sea's ice cover, and forecasting the hazards from current and future storms and providing evidence of their effects in the Baltic coastal zone. The ultimate objective of the project is to implement an operational system for the routine determination and dissemination on the Internet of the above-mentioned features of the Baltic in the form of distribution maps as well as plots, tables and descriptions characterizing the state of the various elements of the Baltic environment

  15. Ocean climate and seal condition

    Directory of Open Access Journals (Sweden)

    Crocker Daniel E

    2005-03-01

    Full Text Available Abstract Background The condition of many marine mammals varies with fluctuations in productivity and food supply in the ocean basin where they forage. Prey is impacted by physical environmental variables such as cyclic warming trends. The weaning weight of northern elephant seal pups, Mirounga angustirostris, being closely linked to maternal condition, indirectly reflects prey availability and foraging success of pregnant females in deep waters of the northeastern Pacific. The aim of this study was to examine the effect of ocean climate on foraging success in this deep-diving marine mammal over the course of three decades, using cohort weaning weight as the principal metric of successful resource accrual. Results The mean annual weaning weight of pups declined from 1975 to the late 1990s, a period characterized by a large-scale, basin-wide warm decadal regime that included multiple strong or long-duration El Niños; and increased with a return to a cool decadal regime from about 1999 to 2004. Increased foraging effort and decreased mass gain of adult females, indicative of reduced foraging success and nutritional stress, were associated with high ocean temperatures. Conclusion Despite ranging widely and foraging deeply in cold waters beyond coastal thermoclines in the northeastern Pacific, elephant seals are impacted significantly by ocean thermal dynamics. Ocean warming redistributes prey decreasing foraging success of females, which in turn leads to lower weaning mass of pups. Annual fluctuations in weaning mass, in turn, reflect the foraging success of females during the year prior to giving birth and signals changes in ocean temperature cycles.

  16. 高速泵机械密封改造%Improved Mechanical Seal in High-speed Pump

    Institute of Scientific and Technical Information of China (English)

    郑齐星; 朱烝

    2000-01-01

    The paper studied the high-speed mechanical seal. Tne transmission mode of high-speed acting-ring was successfully improved and the life of mechanical seal was increased, with a great practical value.%本文通过对高速机械密封运动的研究,成功改进了高速动环的传动方式,大幅度提高了机械密封寿命,具有很高的实用价值。

  17. 楔环连接结构密封的试验研究%Experimental Study of Tightness of Wedged Ring Connection Structure

    Institute of Scientific and Technical Information of China (English)

    马震宇; 孙云龙

    2014-01-01

    针对一种无人水下航行器镁合金圆筒舱段楔环连接和密封结构,分析比较其连接处O形密封圈材料及密封圈表面润滑脂的选择,并通过密封性试验和相容性试验,考察选定的橡胶密封圈的密封性能及选定的润滑脂与橡胶密封圈的相容性。结果表明,三元乙丙橡胶密封圈对该楔环连接结构连接处的气密效果最好,而7608液压系统合成润滑脂与三元乙丙橡胶密封圈相容性优良。%Aimed at the wedged ring connection and seal structure of the Magnesium alloy cylindrical cabins for an un-manned underwater vehicle,the selecting of the O-ring sealing materials in the connection place,and the lubricating grea-ses used in the seal ring surface was analyzed and compared.By the experiments of tightness and compatibility,the tight-ness performance of selected rubber seal and the compatibility of selected lubricating grease with rubber seal rings were in-vestigated.The results show that EPDM rubber seal ring has best air tightness for the wedged ring connection structure, and the 7608 synthetic lubricating grease of hydraulic system has excellent compatibility with the EPDM rubber seal ring.

  18. The Enceladus Ring

    Science.gov (United States)

    2006-01-01

    [figure removed for brevity, see original site] The Enceladus Ring (labeled) This excellent view of the faint E ring -- a ring feature now known to be created by Enceladus -- also shows two of Saturn's small moons that orbit within the ring, among a field of stars in the background. The E ring extends from three to eight Saturn radii -- about 180,000 kilometers (118,000 miles) to 482,000 kilometers (300,000 miles). Its full extent is not visible in this view. Calypso (22 kilometers, or 14 miles across) and Helene (32 kilometers, or 20 miles across) orbit within the E ring's expanse. Helene skirts the outer parts of the E ring, but here it is projected in front of a region deeper within the ring. Calypso and Helene are trojan satellites, or moons that orbit 60 degrees in front or behind a larger moon. Calypso is a Tethys trojan and Helene is a trojan of Dione. An interesting feature of note in this image is the double-banded appearance of the E-ring, which is created because the ring is somewhat fainter in the ringplane than it is 500-1,000 kilometers (300-600 miles) above and below the ringplane. This appearance implies that the particles in this part of the ring have nonzero inclinations (a similar affect is seen in Jupiter's gossamer ring). An object with a nonzero inclination does not orbit exactly at Saturn's ringplane. Instead, its orbit takes it above and below the ringplane. Scientists are not entirely sure why the particles should have such inclinations, but they are fairly certain that the reason involves Enceladus. One possible explanation is that all the E ring particles come from the plume of icy material that is shooting due south out of the moon's pole. This means all of the particles are created with a certain velocity out of the ringplane, and then they orbit above and below that plane. Another possible explanation is that Enceladus produces particles with a range of speeds, but the moon gravitationally scatters any particles that lie very close to

  19. Using otolith microstructure to analyse growth of juvenile Baltic cod Gadus morhua

    DEFF Research Database (Denmark)

    Hüssy, Karin; Mosegaard, Henrik; Hinrichsen, H.H.

    2003-01-01

    otolith growth rates before settling continued to grow fast after settling. On the slope, no relationship between growth before and after settling was found. These results indicate that the different settling habitats occupied by juvenile Baltic cod have different potential for settling and nursery areas.......Pelagic and demersal juvenile Baltic cod Gadus morhua L. were collected on the slope and the top of Rønne bank in the Baltic Sea during 2 cruises in November and December 1998. The growth, age at settling and vertical migration pattern were studied by otolith microstructure analysis...

  20. A summary and revision of the East Baltic Silurian chitinozoan biozonation

    Directory of Open Access Journals (Sweden)

    Viiu Nestor

    2012-11-01

    Full Text Available The biostratigraphical data on the East Baltic Silurian chitinozoans are summarized. Based on the study of nine East Baltic drill cores, 28 regional chitinozoan zonal units, including 26 biozones and 2 interzones, are briefly characterized. In comparison with earlier publications, the Silurian chitinozoan biozonation chart is essentially updated, some biozonal units are added, some renamed and several previous subdivisions have been abolished or replaced. The ranges of the stratigraphically most important chitinozoan species throughout the East Baltic Silurian are discussed. Regional chitinozoan biozones are correlated with the global chitinozoan biozones and graptolite biozones, as well as with the regional stratigraphical units of Estonia, Latvia and the Kaliningrad district.

  1. Fisheries management responses to climate change in the Baltic Sea

    Directory of Open Access Journals (Sweden)

    Thomas Thøgersen

    2015-01-01

    Full Text Available The long term management plan for cod in the eastern Baltic Sea was introduced in 2007 to ensure the full reproductive capacity of cod and an economically viable fishing industry. If these goals are to be fulfilled under changing environmental conditions, a readjustment of the current management plan may be needed. Therefore, this paper investigates the economic impacts of managing the cod, sprat and herring stocks in the eastern Baltic Sea, given on-going climate change, which is known to affect cod recruitment negatively. It is shown that climate change may have severe biological and economic consequences under the current cod management plan and that the negative effects on the economic performance of the fishermen as well as on the abundance of cod can be mitigated by reducing the target fishing mortality rate of cod. These results are obtained by simulating three management scenarios in which the economic consequences of different management objectives for the fishing fleets are assessed through a dynamic multi-species and multi-fleet bio-economic assessment model that include both species interactions and climate change.

  2. Fostering Employee Engagement Through Gamification: AirBaltic Forecaster Tool

    Directory of Open Access Journals (Sweden)

    Daiga Ergle

    2015-09-01

    Full Text Available Next to the employee productivity or indicators for staff turnover and absenteeism in organizations, Employee Engagement stands out as one of the most significant measurements for Human Resource Management efficiency. With younger generation representatives joining the workforce companies are bound to investigate and pursue some of the new tools and techniques that respond more effectively to engagement triggers of generations Y and Z. At AirBaltic Corporation in Riga, Latvia, management has been trying to foster engagement of the workforce through introduction of a business game, called Forecaster. According to management belief, in addition to improved internal communication, Forecaster has potential to save up to 1 million eur annually due to the resulting better quality management decisions. Within the article author looks at the theory and research related to application and effects of gamification within corporate settings, as well as reviews workplace environment at AirBaltic Corporation. Further in the article, Forecaster game is described in more detail and its impact on employee engagement and organizational performance is analysed. Finally, recommendations are drawn for organizations to consider when gamifying people management processes in their organizations.

  3. Nutritional condition and vertical distribution of Baltic cod larvae

    DEFF Research Database (Denmark)

    Grønkjær, P.; Clemmesen, C.; St. John, Michael

    1997-01-01

    Newly hatched Baltic cod Gadus morhua larvae are typically found at depths >60 m. This is a region of low light and prey availability, hence generating the hypothesis that larvae have to migrate from hatching depth to the surface layer to avoid starvation and improve their nutritional condition....... To lest this hypothesis, Baltic cod larvae were sampled during the spawning seasons of 1994 and 1995 with depth-resolving multiple opening/closing nets. Each larva was aged by otolith readings and its RNA/DNA ratio was determined as a measure of nutritional condition. The RNA/DNA ratios of these larvae...... aged 2-25 days (median 10 days) ranged from 0.4 to 6.2, corresponding to levels exhibited by starving and fast growing larvae in laboratory calibration studies (starvation, protein growth rate, G(pi)=-12.2% day(-1); fast-growing larvae, G(pi)=14.1% day(-1)) respectively. Seventy per cent of the field...

  4. Adaptive governance of the Baltic Sea - lessons from elsewhere

    Directory of Open Access Journals (Sweden)

    Matilda Valman

    2015-03-01

    Full Text Available Governance of marine resources is increasingly characterized by integrated, cross sectoral and ecosystem based approaches. Such approaches require that existing governing bodies have an ability to adapt to ecosystem dynamics, while also providing transparent and legitimate outcomes. Here, we investigate how the Baltic Marine Environment Protection Commission (HELCOM, the international governing body for the Baltic Sea, could improve its prospects for working with the ecosystem approach, drawing from the literature on adaptive governance. We construct an ideal type of adaptive governance to which we compare the way in which HELCOM is operating and relate these dynamics to two other international marine environment governance organizations, the Coral Triangle Initiative on Coral Reefs, Fisheries and Food Security (CTI-CFF and the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR. We conclude that HELCOM deviates from an ideal type of adaptive governance in several ways but also that the other two case studies provide empirical support for potential ways in which HELCOM could improve its adaptive capacity. Key aspects where HELCOM could improve include increasing stakeholder participation – both in information sharing and decision making. Further, HELCOM need to develop evaluation mechanisms, secure compliance to improve adaptive capacity and organizational effectiveness, which entails the development of structures for conflict resolution. Finally, HELCOM need to increase communication and harmonization between different levels of authority.

  5. Projected future climate change and Baltic Sea ecosystem management.

    Science.gov (United States)

    Andersson, Agneta; Meier, H E Markus; Ripszam, Matyas; Rowe, Owen; Wikner, Johan; Haglund, Peter; Eilola, Kari; Legrand, Catherine; Figueroa, Daniela; Paczkowska, Joanna; Lindehoff, Elin; Tysklind, Mats; Elmgren, Ragnar

    2015-06-01

    Climate change is likely to have large effects on the Baltic Sea ecosystem. Simulations indicate 2-4 °C warming and 50-80 % decrease in ice cover by 2100. Precipitation may increase ~30 % in the north, causing increased land runoff of allochthonous organic matter (AOM) and organic pollutants and decreased salinity. Coupled physical-biogeochemical models indicate that, in the south, bottom-water anoxia may spread, reducing cod recruitment and increasing sediment phosphorus release, thus promoting cyanobacterial blooms. In the north, heterotrophic bacteria will be favored by AOM, while phytoplankton production may be reduced. Extra trophic levels in the food web may increase energy losses and consequently reduce fish production. Future management of the Baltic Sea must consider the effects of climate change on the ecosystem dynamics and functions, as well as the effects of anthropogenic nutrient and pollutant load. Monitoring should have a holistic approach, encompassing both autotrophic (phytoplankton) and heterotrophic (e.g., bacterial) processes.

  6. Earth: A Ringed Planet?

    Science.gov (United States)

    Hancock, L. O.; Povenmire, H.

    2010-12-01

    Among the most beautiful findings of the Space Age have been the discoveries of planetary rings. Not only Saturn but also Jupiter, Uranus and Neptune have rings; Saturn’s ring system has structures newly discovered; even Saturn's moon Rhea itself has a ring. All these are apparently supplied by material from the planetary moons (Rhea's ring by Rhea itself). The question naturally arises, why should the Earth not have a ring, and on the other hand, if it does, why has it not been observed? No rings have yet been observed in the inner solar system, but after all, rings in the inner solar system might simply tend to be fainter and more transient than those of the outer solar system: the inner solar system is more affected by the solar wind, and the Sun’s perturbing gravitational influence is greater. J.A. O’Keefe first suggested (1980) that Earth might have a ring system of its own. An Earth ring could account for some climate events. O’Keefe remarked that formation or thickening of a ring system in Earth’s equatorial plane could drive glaciation by deepening the chill of the winter hemisphere. (It is very well established that volcanic dust is an effective agent for the extinction of sunlight; this factor can be overwhelmingly apparent in eclipse observations.) O’Keefe died in 2000 and the speculation was not pursued, but the idea of an Earth ring has a prima facie reasonableness that calls for its renewed consideration. The program of this note is to hypothesize that, as O’Keefe proposed: (a) an Earth ring system exists; (b) it affects Earth's weather and climate; (c) the tektite strewn fields comprise filaments of the ring fallen to Earth's surface on various occasions of disturbance by comets or asteroids. On this basis, and drawing on the world's weather records, together with the Twentieth Century Reanalysis by NCEP/CIRES covering the period 1870-2010 and the geology of the tektite strewn fields, we herein propose the hypothesized Earth ring

  7. Local loop near-rings

    OpenAIRE

    Franetič, Damir

    2015-01-01

    We study loop near-rings, a generalization of near-rings, where the additive structure is not necessarily associative. We introduce local loop near-rings and prove a useful detection principle for localness.

  8. Tamper-indicating quantum optical seals

    Energy Technology Data Exchange (ETDEWEB)

    Humble, Travis S [ORNL; Williams, Brian P [ORNL

    2015-01-01

    Confidence in the means for identifying when tampering occurs is critical for containment and surveillance technologies. Fiber-optic seals have proven especially useful for actively surveying large areas or inventories due to the extended transmission range and flexible layout of fiber. However, it is reasonable to suspect that an intruder could tamper with a fiber-optic sensor by accurately replicating the light transmitted through the fiber. In this contribution, we demonstrate a novel approach to using fiber-optic seals for safeguarding large-scale inventories with increased confidence in the state of the seal. Our approach is based on the use of quantum mechanical phenomena to offer unprecedented surety in the authentication of the seal state. In particular, we show how quantum entangled photons can be used to monitor the integrity of a fiber-optic cable - the entangled photons serve as active sensing elements whose non-local correlations indicate normal seal operation. Moreover, we prove using the quantum no-cloning theorem that attacks against the quantum seal necessarily disturb its state and that these disturbances are immediately detected. Our quantum approach to seal authentication is based on physical principles alone and does not require the use of secret or proprietary information to ensure proper operation. We demonstrate an implementation of the quantum seal using a pair of entangled photons and we summarize our experimental results including the probability of detecting intrusions and the overall stability of the system design. We conclude by discussing the use of both free-space and fiber-based quantum seals for surveying large areas and inventories.

  9. Heavy ion storage rings

    Energy Technology Data Exchange (ETDEWEB)

    Schuch, R.

    1987-01-01

    A brief overview of synchrotron storage rings for heavy ions, which are presently under construction in different accelerator laboratories is given. Ions ranging from protons up to uranium ions at MeV/nucleon energies will be injected into these rings using multiturn injection from the accelerators available or being built in these laboratories. After injection, it is planned to cool the phase space distribution of the ions by merging them with cold electron beams or laser beams, or by using stochastic cooling. Some atomic physics experiments planned for these rings are presented.

  10. 自适应接触式机械密封性能研究%Sealing Performance of Adaptive Contacting Mechanical Seal

    Institute of Scientific and Technical Information of China (English)

    赵星宇; 刘莹; 高志; 黄伟锋; 刘向锋; 王玉明

    2015-01-01

    The mechanism of a kind of adaptive contacting mechanical seal which is applied in pressurized water reactor nuclear coolant pumps in different operating conditions is investigated by the hybrid lubrication model coupled with thermal and elastic deformation and elastic hydrodynamic lubrication model. The floating structure of static ring with O-ring is given, and its performance is compared with interferential structure applied in import product. A full-scale vertical experiment rig for adaptive contacting mechanical seal is set up. The seal performance of the adaptive contacting mechanical seal in two statuses is obtained from the experiments which prove the two theoretical models. The feasibility and reliability of floating structure of static ring is verified by the experiments also. These results are beneficial to the domestic design and manufacturing of mechanical seals in nuclear coolant pump.%以压水堆核主泵静压轴封系统中具有自适应性的接触式机械密封为对象,分别采用热流固耦合混合润滑和流固耦合流体润滑模型,研究了不同工况下密封性能演变规律;提出了具有更好工艺性能的静环组件浮动安装结构并与国外产品采用的镶装结构密封性能进行了比较。自行研制了立式、全尺寸自适应接触式机械密封性能试验系统,获得自适应接触式机械密封在核主泵密封两种典型工作状态下的密封性能,验证了理论分析模型。同时,通过试验验证了静环组件浮动安装结构的可行性与性能,为国产化设计与制造提供了理论和实践基础。

  11. Vacuum-sealed casting process under pressure

    Institute of Scientific and Technical Information of China (English)

    LI Chen-xi; GUO Tai-ming; WU Chun-jing; WANG Hong

    2006-01-01

    A new casting method, the vacuum-sealed mold casting under pressure, has been developed, and thin wall iron castings with high precision and smooth surface have been produced successfully with this casting method. The experimental results show that the liquid iron has a very excellent filling ability because a high negative pressure is formed in the mold cavity during filling process. The vacuum-sealed mold under pressure has very high compressive strength greater than 650 kPa, which is 3-4 times as high as that of the molds produced by high-pressure molding process or vacuum-sealed molding process.

  12. Compliant Glass Seals for SOFC Stacks

    Energy Technology Data Exchange (ETDEWEB)

    Chou, Y. S.; Choi, Jung-Pyung; Xu, Wei; Stephens, Elizabeth V.; Koeppel, Brian J.; Stevenson, Jeffry W.; Lara-Curzio, Edgar

    2014-04-01

    This report summarizes results from experimental and modeling studies performed by participants in the Solid-State Energy Conversion Alliance (SECA) Core Technology Program, which indicate that compliant glass-based seals offer a number of potential advantages over conventional seals based on de-vitrifying glasses, including reduced stresses during stack operation and thermal cycling, and the ability to heal micro-damage induced during thermal cycling. The properties and composition of glasses developed and/or investigated in these studies are reported, along with results from long-term (up to 5,800h) evaluations of seals based on a compliant glass containing ceramic particles or ceramic fibers.

  13. Infiltrating/sealing proximal caries lesions

    DEFF Research Database (Denmark)

    Martignon, S; Ekstrand, K R; Gomez, J

    2012-01-01

    This randomized split-mouth controlled clinical trial aimed at assessing the therapeutic effects of infiltration vs. sealing for controlling caries progression on proximal surfaces. Out of 90 adult students/patients assessed at university clinics and agreeing to participate, 39, each with 3...... differences in lesion progression between infiltration and placebo (P = 0.0012) and between sealing and placebo (P = 0.0269). The study showed that infiltration and sealing are significantly better than placebo treatment for controlling caries progression on proximal lesions. No significant difference...

  14. Compliant Glass Seals for SOFC Stacks

    Energy Technology Data Exchange (ETDEWEB)

    Chou, Yeong -Shyung [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Choi, Jung-Pyung [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Xu, Wei [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Stephens, Elizabeth V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Koeppel, Brian J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Stevenson, Jeffry W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lara-Curzio, Edgar [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2014-04-30

    This report summarizes results from experimental and modeling studies performed by participants in the Solid-State Energy Conversion Alliance (SECA) Core Technology Program, which indicate that compliant glass-based seals offer a number of potential advantages over conventional seals based on de-vitrifying glasses, including reduced stresses during stack operation and thermal cycling, and the ability to heal micro-damage induced during thermal cycling. The properties and composition of glasses developed and/or investigated in these studies are reported, along with results from long-term (up to 5,800h) evaluations of seals based on a compliant glass containing ceramic particles or ceramic fibers.

  15. Floating air riding seal for a turbine

    Energy Technology Data Exchange (ETDEWEB)

    Ebert, Todd A

    2016-08-16

    A floating air riding seal for a gas turbine engine with a rotor and a stator, an annular piston chamber with an axial moveable annular piston assembly within the annular piston chamber formed in the stator, an annular cavity formed on the annular piston assembly that faces a seal surface on the rotor, where the axial moveable annular piston includes an inlet scoop on a side opposite to the annular cavity that scoops up the swirling cooling air and directs the cooling air to the annular cavity to form an air cushion with the seal surface of the rotor.

  16. Rings Research in the Next Decade

    Science.gov (United States)

    Burns, J. A.; Tiscareno, M. S.

    2009-12-01

    -based observations. Members of the Rings White Paper Team include: Matthew S. Tiscareno (Cornell U), Nicole Albers (U of Colorado), Todd Bradley (U of Central Florida), André Brahic (U of Paris, France), Shawn Brooks (JPL), Joseph Burns (Cornell U), Carlos Chavez (UNAM, Mexico), Joshua Colwell (U of Central Florida), Jeff Cuzzi (NASA Ames), Imke de Pater (U of California), Luke Dones (SwRI), Richard Durisen (Indiana U), Michael Evans (Cornell U), Cecile Ferrari (CEA Saclay, France), Gianrico Filacchione (INAF-IASF, Italy), Silvia Giuliatti Winter (UNESP, Brazil), Mitch Gordon (SETI), Amara Graps (SwRI), Eberhard Gruen (MPI, Germany), Douglas Hamilton (U of Maryland), Matthew Hedman (Cornell U), Mihaly Horanyi (U of Colorado), Sascha Kempf (MPI, Germany), Harald Krueger (MPI, Germany), Steve Larson (U of Arizona), Mark Lewis (Trinity U), Jack Lissauer (NASA Ames), Colin Mitchell (CICLOPS/SSI), Carl Murray (QMUL, England), Philip Nicholson (Cornell U), Cathy Olkin (SwRI), Robert Pappalardo (JPL), Frank Postberg (MPI, Germany), Heikki Salo (U of Oulu, Finland), Juergen Schmidt (U of Potsdam, Germany), David Seal (JPL), Mark Showalter (SETI), Frank Spahn (U of Potsdam, Germany), Linda Spilker (JPL), Joseph Spitale (CICLOPS/SSI), Ralf Srama (MPI, Germany), Miodrag Sremcevic (U of Colorado), Glen Stewart (U of Colorado), John Weiss (Carleton College), Padma Yanamandra-Fisher (JPL)

  17. Investigating the sealing capacity of a seal system in rock salt (DOPAS project)

    Energy Technology Data Exchange (ETDEWEB)

    Jantschik, Kyra; Moog, Helge C.; Czaikowski, Oliver; Wieczorek, Klaus [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) gGmbH, Braunschweig (Germany)

    2016-11-15

    This paper describes research and development work on plugging and sealing repositories, an issue of fundamental importance for the rock salt option which represents one of the three European repository options, besides the clay rock and the crystalline rock options. The programme aims at providing experimental data needed for the theoretical analysis of the long-term sealing capacity of concrete- based sealing materials. In order to demonstrate hydro-mechanical material stability under representative load scenarios, a comprehensive laboratory testing programme is carried out. This comprises investigation of the sealing capacity of the combined seal system and impact of the so-called excavation-damaged zones (EDZ) as well as investigation of the hydro-chemical long-term stability of the seal in contact with different brines under diffusive and advective conditions. This paper presents experimental approaches and preliminary results from laboratory investigations on salt concrete and combined systems as obtained to date.

  18. Effect of bar sealing parameters on OPP/MCPP heat seal strength

    Directory of Open Access Journals (Sweden)

    2007-11-01

    Full Text Available The effect of bar sealing parameters on the heat seal strength of oriented polypropylene (OPP/metallic cast polypropylene (MCPP laminate film was investigated. Based on the results obtained from the parametric study, a bar sealing process window was developed. All points drop within the process window are combinations of platen temperature and dwell time that produce acceptable heat seal. Optimum combinations are indicated by the lower border of the window. The plateau initiation temperature, Tpi of OPP/MCPP laminate film used in the present study occurred before the final melting temperature, Tmf of the sealant material. The highest achievable heat seal strength was at the plateau region, and the corresponding failure modes were delaminating, tearing or combine failure modes (delaminating and tearing. Minimum pressure level of 1.25 bars is necessary to bring the laminate interface into intimate contact in order to effect sealing.

  19. The g-2 ring

    CERN Multimedia

    1974-01-01

    The precise measurement of "g-2", the anomalous magnetic moment of the muon, required a special muon storage ring with electrostatic focussing and very accurate knowledge of the magnetic bending field. For more details see under photo 7405430.

  20. Modified Newton's rings: II

    CERN Document Server

    Chaitanya, T Sai; Krishna, V Sai; Anandh, B Shankar; Umesh, K S

    2010-01-01

    In an earlier work (Shankar kumar Jha, A Vyas, O S K S Sastri, Rajkumar Jain & K S Umesh, 'Determination of wavelength of laser light using Modified Newton's rings setup', Physics Education, vol. 22, no.3, 195-202(2005)) reported by our group, a version of Newton's rings experiment called Modified Newton's rings was proposed. The present work is an extension of this work. Here, a general formula for wavelength has been derived, applicable for a plane of observation at any distance. A relation between the focal length and the radius curvature is also derived for a plano-convex lens which is essentially used as a concave mirror. Tracker, a video analysis software, freely downloadable from the net, is employed to analyze the fringes captured using a CCD camera. Two beams which give rise to interference fringes in conventional Newton's rings and in the present setup are clearly distinguished.

  1. Finite Element Analysis of Elastomeric Seals for LIDS

    Science.gov (United States)

    Oswald, Jay J.; Daniels, Christopher C.

    2007-01-01

    Objective: Create a means of evaluating seals w/o prototypes. Motivation: Cost Prototype 54" seal approx.$100k per seal pair FEA license + high end workstation approx. $30k per year. Development time: 6 months lead time for a new seal design Many designs per day (solution time <1 minute) Understanding: Difficult to experimentally measure strains, contact pressure profile, stresses, displacements

  2. Changes in patterns of persistent halogenated compounds through a pelagic food web in the Baltic Sea

    DEFF Research Database (Denmark)

    Stephansen, Diana Agnete; Svendsen, Tore Christian; Vorkamp, Katrin

    2012-01-01

    The concentrations and patterns of persistent halogenated compounds (PHCs), including polychlorinated biphenyls (PCBs), DDT, hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB) and polybrominated diphenyl ethers (PBDEs) were examined in a pelagic food web from the southern Baltic Sea consisting...

  3. Real Estate Price Bubble and Its Impact in the Baltic States

    Directory of Open Access Journals (Sweden)

    Laura Tupėnaitė

    2011-04-01

    Full Text Available The article analyses the problem of the real estate price bubble in the Baltic States. The definition of the real estate price bubble is discussed, the main reasons as well as bubble influencing fundamental and irrational factors and price bubble burst sequences to national economics are analysed. Based on the research model and developed by the authors, the practical research of the real estate market in the Baltic States was performed.Trends towards the real estate prices were researched and the influence of fundamental and irrational factors on the growth of the real estate prices was discussed. Research results proved the existence of the price bubble in the Baltic States real estate market during the period from 2004 to 2006. The influence of the real estate price bubble burst on the national economy of the Baltic States is discussed at the end of this article. Article in Lithuanian

  4. Baltic Listed Companies´ disclosure quality – far ahead or lagging behind?

    Directory of Open Access Journals (Sweden)

    Imbi Karmo

    2014-08-01

    Full Text Available The objective of this paper is to determine the level of average quality of disclosures made in English by biggest companies listed on Baltic stock exchanges and to analyse it in the context of biggest companies listed on other Central and Eastern European (CEE and three developed European (EU stock exchanges. Content analysis reveals that the disclosure quality level of Baltic listed companies outperforms that of other CEE peers by at least 30% and in the context of stock exchange web page disclosures 50 to 80%. Compared to companies listed on developed EU stock exchanges, the disclosure quality of Baltic listed companies is slightly lower in the company home page category, however, it outperforms in the context of stock exchange web page disclosures. This result raises concerns about possibly too restrictive stock exchange web page disclosure regulations which may have a negative impact on the future outlook of Baltic stock exchanges.

  5. Long-term temporal and spatial trends in eutrophication status of the Baltic Sea

    DEFF Research Database (Denmark)

    Andersen, Jesper; Carstensen, Jacob; Conley, Daniel J.

    2017-01-01

    Much of the Baltic Sea is currently classified as ‘affected by eutrophication’. The causes for this are twofold. First, current levels of nutrient inputs (nitrogen and phosphorus) from human activities exceed the natural processing capacity with an accumulation of nutrients in the Baltic Sea over...... report on the temporal and spatial trends of eutrophication status for the open Baltic Sea over a 112-year period using the HELCOM Eutrophication Assessment Tool (HEAT 3.0). Further, we analyse variation in the confidence of the eutrophication status assessment based on a systematic quantitative approach...... using coefficients of variation in the observations. The classifications in our assessment indicate that the first signs of eutrophication emerged in the mid-1950s and the central parts of the Baltic Sea changed from being unaffected by eutrophication to being affected.We document improvements...

  6. Evolution study of contamination Russian Baltic fish by PCDD/F and WHO-PCB

    Energy Technology Data Exchange (ETDEWEB)

    Shelepchikov, A.; Brodsky, E. [Inst. of Ecology and Evolution of Russian Academy of Sciences (IPEE RAS) (Russian Federation); Shenderyuk, V.; Baholdina, L. [Atlantic Research Inst. of Fish Industry and Oceanography, (AtlantNIRO) (Russian Federation)

    2004-09-15

    Baltic Sea is well known as the most polluted sea in the world, but its fish products have a significant role in diet of Baltic countries habitants. In Dioxin 2003 meeting we have present first results of analysis of Baltic fishes caught by Russian fisherman for market. The results confirmed a rather high level of pollution in the Baltic seafood by PCDD/Fs and have shown necessity of the further researches. Although PCDD/Fs profile in fisher's body is not consist unsteady and was formed under affection of various factors, it was obvious that essential path comes with PCB; also previously were found that WHO-TEQ{sub PCB} in seafood could exceed WHO-TEQ{sub PCDD/F} level. In given works we present results of the analysis of two freshwater species of fishes and updating research of former analyzed kinds, included of WHO-PCBs determination.

  7. [Balti biidermeier. Panoraame ja lähivaatlusi = Baltic biedermeier. Panoramas and introspections] / Konrad Maier

    Index Scriptorium Estoniae

    Maier, Konrad, 1958-

    2012-01-01

    Arvustus: Balti biidermeier. Panoraame ja lähivaatlusi = Baltic biedermeier. Panoramas and introspections (Proceedings of the Art Museum of estonia, 1 (6)). Hrsg. von Anu Allikvee und Tiina-Mall Kreem. (Tallinn, 2011)

  8. Baltic Graduate School for Social Sciences and Humanities founded in Tallinn / Maiki Voore

    Index Scriptorium Estoniae

    Voore, Maiki, 1983-

    2009-01-01

    Oktoobris 2008 allkirjastasid Tallinna Ülikooli, Läti Ülikooli ja Kaunase Vytautas Magnuse Ülikooli rektorid Baltimaade sotsiaal- ja humanitaarteaduste doktorikooli (Baltic Graduate School) asutamislepingu

  9. [Perceptions of Loss, Decline and Doom in the Baltic Sea - Untergangsvorstellungen im Ostseeraum] / David Feest

    Index Scriptorium Estoniae

    Feest, David, 1969-

    2011-01-01

    Arvustus : Perceptions of Loss, Decline and Doom in the Baltic Sea - Untergangsvorstellungen im Ostseeraum. Berlin : Berliner Wissenschafts-Verlag, 2004. (Die Ostseeregione: Nördliche Dimensionen - Europäische Perspektiven. 1)

  10. Model simulation of inflow water to the Baltic Sea based on 129I

    DEFF Research Database (Denmark)

    Yi, P.; Chen, X.G.; Bao, D.X.;

    2013-01-01

    is crucial for estimating potential environmental risks as well as to find the best remedial strategy. We present here a model to estimate water inflow from the North Sea to the Baltic Sea by utilizing 129I as a tracer. The results predicted inflow range of 230-450 km3/y with best fit value around 330 km3/y...... from the North Sea to the Baltic Sea during 1980-1999. Despite limited time series data on 129I, the model presented here demonstrates a new management tool for the Baltic Sea to calculate inflow water compared to conventional methods (such as salinity, temperature and hydrographic models). Crown......The semi-enclosed Baltic Sea represents a vital economic and recreational resource for more than 90 million people inhabiting its coasts. Extensive contamination of this sea by a variety of anthropogenic pollutants has raised the concern of the people in the region. Quantifying seawater inflow...

  11. What we know about the Baltic Sea: a summary of BSSC 2005

    Directory of Open Access Journals (Sweden)

    Szymon Uścinowicz

    2006-06-01

    Full Text Available Introduction    The Baltic Sea, an internal sea of the European Community, isone of the largest brackish water bodies in the world. It isquite unique in many respects, particularly in its natural featuresand in the cultural, political and socio-economic patterns ofthe countries bordering it.    After nearly 40 years, during which Baltic marine physicists,chemists, biologists and geologists had been holding separatescientific meetings, it was decided the time was ripe to arrangejoint scientific conferences with the purpose of getting togetherto discuss general and specific aspects of the Baltic Sea, toexchange information, to integrate efforts, and to get to knowand understand each other better. The Sopot 2005 Congress, precededby the Baltic Sea Science Congresses in Rønne (1997, Warnemünde(1999, Stockholm (2001 and Helsinki (2003, was the fifth jointmeeting of the Conference of Baltic Oceanographers (CBO, BalticMarine Biologists (BMB and Baltic Sea Geologists (BSG. Likeall the previous congresses, the one held in Sopot bore witnessto the idea that we all, members of CBO, BMB and BSG, shouldcontinue to work together even more closely.    The meeting in Sopot instigated discussion on a broad spectrumof problems, from large-scale climate change-related processesto local, small-scale specific Baltic Sea features. Further subjectsfor deliberation included modelling as a research tool and asa way of providing services and forecasting certain phenomena,operational oceanography, and man's impact on the Baltic Seaenvironment and its resources.    We are indebted to our Scientific Committee for their work duringthe past months to sort out and select interesting contributionsto all the oral and poster sessions, and thus for making theCongress an attractive and quality event. We also thank the PolishAcademy of Sciences and the City of Sopot for their financialsupport.    We hope that the joint Congress and fruitful scientific

  12. Improved Gas Seal for Electrolytic Cells

    Science.gov (United States)

    Richter, R.

    1984-01-01

    Breakage by differential thermal expansion reduced. Cells for hot electrolysis of gases improved by design that reduces vulnerability of gas seals to breakage at operating temperature of about 1000 degrees C.

  13. HMSRP Hawaiian Monk Seal Survival Factors

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains records of survival factors recorded by PSD personnel and cooperating scientists as part of the ongoing monk seal population assessment...

  14. HMSRP Hawaiian Monk Seal Survey Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains records of Hawaiian monk seal and green turtle sightings in the Northwestern Hawaiian Islands (NWHI) since 1982 at Lisianski Island, and since...

  15. HMSRP Hawaiian Monk Seal Tag Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains records for all tags applied to Hawaiian monk seals since 1981. These tags were applied by PSD personnel and cooperating scientists as part of...

  16. HMSRP Hawaiian Monk Seals on Social Media

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — As social media platforms develop, they potentially provide valuable information for wildlife researchers and managers. NOAA’s Hawaiian Monk Seal Research Program...

  17. HMSRP Hawaiian Monk Seal Necropsy Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains information on Hawaiian monk seal gross necropsy (in some cases only field notes or minimal information) and histopathology results beginning...

  18. HMSRP Hawaiian Monk Seal Photo Identification Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This photo collection contains identification and other images and video of Hawaiian monk seals taken by PSD personnel and cooperating scientists as part of the...

  19. Temporary fire sealing of penetrations on TFTR

    Energy Technology Data Exchange (ETDEWEB)

    Hondorp, H.L.

    1981-02-01

    The radiation shielding provided for TFTR for D-D and D-T operation will be penetrated by numerous electrical and mechanical services. Eventually, these penetrations will have to be sealed to provide the required fire resistance, tritium sealability, pressure integrity and radiation attenuation. For the initial hydrogen operation, however, fire sealing of the penetrations in the walls and floor is the primary concern. This report provides a discussion of the required and desirable properties of a temporary seal which can be used to seal these penetrations for the hydrogen operation and then subsequently be removed and replaced as required for the D-D and D-T operations. Several candidate designs are discussed and evaluated and recommendations are made for specific applications.

  20. Properties of Sealing Materials in Groundwater Wells

    DEFF Research Database (Denmark)

    Köser, Claus

    on the maximum swelling pressure; i) the bulk density of the sample, and ii) whether the sample is sorted or unsorted. CT scans (Computed Tomography) have been used to evaluate certain properties of bentonite seals in a limited volume. In this context, a set of algorithms to convert CT numbers (HU unit......) into densities for clay/water systems has been developed. This method has successfully been used to evaluate e.g., macroporosity, homogenization of the bentonite seal during the hydration of water, hydraulic conductivity and the creation of channels in the bentonite seals. Based on the results obtained...... in this Ph.D. thesis, a number of recommendations has been offered; i) a change regarding the production of pellets and ii) how sealing material must be treated in the actual construction of groundwater wells....