Relevant bibliographies by topics / Seam contamination

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Seam contamination'

Author: Grafiati
Published: 4 June 2021
Last updated: 13 February 2022

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Seam contamination.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Seam contamination"

1

Nehls, T., G. Jozefaciuk, Z. Sokolowska, M. Hajnos, and G. Wessolek. "Filter properties of seam material from paved urban soils." Hydrology and Earth System Sciences 12, no. 2 (2008): 691–702. http://dx.doi.org/10.5194/hess-12-691-2008.

Full text
Abstract:
Abstract. Depositions of all kinds of urban dirt and dust including anthropogenic organic substances like soot change the filter properties of the seam filling material of pervious pavements and lead to the formation of a new soil substrate called seam material. In this study, the impact of the particular urban form of organic matter (OM) on the seam materials CECpot, the specific surface area (As), the surface charge density (SCD), the adsorption energies (Ea) and the adsorption of Cd and Pb were assessed. The Cd and Pb displacement through the pavement system has been simulated in order to assess the risk of soil and groundwater contamination from infiltration of rainwater in paved urban soils. As, Ea and SCD derived from water vapor adsorption isotherms, CECpot, Pb and Cd adsorption isotherms where analyzed from adsorption experiments. The seam material is characterized by a darker munsell-color and a higher Corg (12 to 48g kg-1) compared to the original seam filling. Although, the increased Corg leads to higher As (16m2g-1) and higher CECpot (0.7 to 4.8cmolckg-1), with 78cmolckg-1C its specific CECpot is low compared to OM of non-urban soils. This can be explained by a low SCD of 1.2×10-6molc m-2 and a low fraction of high adsorption energy sites which is likely caused by the non-polar character of the accumulated urban OM in the seam material. The seam material shows stronger sorption of Pb and Cd compared to the original construction sand. The retardation capacity of seam material for Pb is similar, for Cd it is much smaller compared to natural sandy soils with similar Corg concentrations. The simulated long term displacement scenarios for a street in Berlin do not indicate an acute contamination risk for Pb . For Cd the infiltration from puddles can lead to a breakthrough of Cd through the pavement system during only one decade. Although they contain contaminations itself, the accumulated forms of urban OM lead to improved filter properties of the seam material and may retard contaminations more effectively than the originally used construction sand.
APA, Harvard, Vancouver, ISO, and other styles
2

Su, Xianbo, Fengde Zhou, and Stephen Tyson. "Numerical investigation of the potential contamination of a shallow aquifer in producing coalbed methane." Energy Exploration & Exploitation 36, no. 2 (2017): 282–96. http://dx.doi.org/10.1177/0144598717736629.

Full text
Abstract:
This paper presents a study on the impact of well integrity failure on coalbed methane (also known as coal seam gas) production and potential shallow water contamination using numerical simulations with a finite-difference method. Two connection types and 12 cases were simulated: Type A – leakage through cement sheath and Type B – impaired zonal isolation at the aquifer interval. The effect of the distance between the aquifer and the coal seam, drainage area and desorption time on gas and water production was also inspected. Results show that both connection types have strong effects on the gas and water production; the cumulative water and gas production increases with increasing drainage radius; the distance between aquifer and the coal seam has a negative effect on the water production but a negligible effect on the gas production; desorption time, ranging from 5 to 30 days, has a negligible effect on the water and gas production. Connection Type A yields a potential water contamination but connection Type B does not. Gas concentration in the shallow aquifer decreases sharply with an increase of distance away from the producer and the unsafe area are within an area with a radius ranging from approximately 50 m to 90 m away from the producer in this study.
APA, Harvard, Vancouver, ISO, and other styles
3

Nehls, T., G. Jozefaciuk, Z. Sokolowska, M. Hajnos, and G. Wessolek. "Filter properties of seam material from paved urban soils." Hydrology and Earth System Sciences Discussions 4, no. 4 (2007): 2625–57. http://dx.doi.org/10.5194/hessd-4-2625-2007.

Full text
Abstract:
Abstract. We studied pavement seam material. This is the soil substrate in joints of pervious pavements in urban areas. It is mostly 1 cm thick and develops from the original seam filling by depositions of all kinds of urban residues, including anthropogenic organic substances. It was investigated, how this unique form of organic matter influences the filter properties of seam material and how the seam material influences heavy metal transport through the pavement. The seam material is characterised by a darker munsell colour, higher organic carbon content, higher surface areas, higher cation exchange capacities, but a lower fraction of high adsorption energy sites compared to the original seam filling. The deposited anthropogenic organic matter itself could be characterised as particulate and non-polar. Compared to natural soils, it has a small surface area and a low surface charge density resulting in a small cation exchange capacity of only 75 cmol(+) kg−1C. The seam material shows stronger sorption of Pb and Cd compared to the original construction sand. The retardation capacity of seam material towards Pb is similar, towards Cd it is much smaller compared to natural soils. The simulated long term displacement scenarios for a street in Berlin do not indicate an acute contamination risk for Pb. For Cd the infiltration from ponds can lead to a displacement of Cd during only one decade.
APA, Harvard, Vancouver, ISO, and other styles
4

Blankl, A., and Manfred Geiger. "Investigations on Seam Quality in Laser Beam Welding of Contaminated, Zinc Coated Sheets." Advanced Materials Research 6-8 (May 2005): 187–94. http://dx.doi.org/10.4028/www.scientific.net/amr.6-8.187.

Full text
Abstract:
The customers’ demand for high quality and low cost products with rising functionality forces the enterprises to cost savings. In production these cost savings can be accomplished by simplification or omission of handling operations in the process chain. In laser beam welding of stamped sheet metals a previous cleaning of the sheets is usually necessary to guarantee a sufficient seam quality at a lap joint. Due to the recent trend towards low use of lubricants in forming operations the question arises, whether this process could be avoided in order to lower the production costs. The disadvantage of this measure would be a degradation of the seam quality. This reduction shows up in a falling strength of the weld due to inclusions and pore formation. This paper deals with the impact of different types of contaminations on the quality of laser welding. Therefore several liquid (oils) and solid (metallic and non-metallic) contaminants are examined. Zinc coated sheets are investigated too, because a zinc contamination arises with these sheets in the welding operation. The zinc coating evaporates because of the high temperature and this leads to a high porosity in the welding seam. In both cases also the height of the gap between the two sheets is varied in order to investigate its influence on the weld. To reduce the effort of the investigations, but not the accuracy of the results, the laboratory trials were supported by the methods of design of experiments. After the welding operation, the quality of the welding seam is evaluated by means of its mechanical properties and tightness. The results of the investigations are discussed and the developed solution strategies are presented.
APA, Harvard, Vancouver, ISO, and other styles
5

Gonzalez, Dennis, Sreekanth Janardhanan, Daniel E. Pagendam, and Daniel W. Gladish. "Probabilistic Groundwater Flow, Particle Tracking and Uncertainty Analysis for Environmental Receptor Vulnerability Assessment of a Coal Seam Gas Project." Water 12, no. 11 (2020): 3177. http://dx.doi.org/10.3390/w12113177.

Full text
Abstract:
The production of coalbed methane, or coal seam gas (CSG) in Australia increased 250-fold since the 1990s to around 1502 petajoules in 2019 and continues to expand. Groundwater flow in the aquifers intersected by gas wells could potentially facilitate a transport pathway for migration of contaminants or poorer quality water from deeper formations. While regulatory and mitigation mechanisms are put in place to minimize the risks, quantitative environmental impact assessments are also undertaken. When many gas wells are drilled in a wide area where many potential receptors are also spatially distributed, potential source-receptor combinations are too numerous to undertake detailed contamination risk assessment using contaminant transport modelling. However, valuable information can be gleaned from the analysis of groundwater flow directions and velocities to inform and prioritise contamination risk assessment and can precede computationally challenging stochastic contaminant transport modelling. A probabilistic particle tracking approach was developed as a computationally efficient screening analysis of contamination pathways for a planned CSG development near Narrabri in northern New South Wales, Australia. Particle tracking was run iteratively with a numerical groundwater flow model across a range of plausible parameter sets to generate an ensemble of estimated flow paths through the main Great Artesian Basin aquifer in the area. Spatial patterns of path lines and spatial relationships with potential receptors including neighbouring groundwater extraction wells and hydrologically connected ecological systems were analysed. Particle velocities ranged from 0.5 to 11 m/year and trajectories indicated dedicated contaminant transport modeling would be ideally focused at the local scale where wells are near potential receptors. The results of this type of analysis can inform the design of monitoring strategies and direct new data collection to reduce uncertainty and improve the effectiveness of adaptive management strategies and early detection of impacts.
APA, Harvard, Vancouver, ISO, and other styles
6

Li, Shaodong, Gangwei Fan, Dongsheng Zhang, et al. "Fracture Propagation and Hydraulic Properties of a Coal Floor Subjected to Thick-Seam Longwalling above a Highly Confined Aquifer." Geofluids 2021 (July 2, 2021): 1–12. http://dx.doi.org/10.1155/2021/6668644.

Full text
Abstract:
The high-pressure and water-rich confined aquifer occurring in the Ordovician limestone sequence poses great threats to the routine production of underground longwall mining. Considering the intense cooperation of mining disturbance and water pressure, water-conducting fractures within a coal seam floor can connect the lower aquifer and upper goaf, and this hydraulic behavior is considered the root of water inrush hazard and water loss or contamination. In this paper, the panel 4301 of the Longquan coal mine serves as the case where the panel works closely above the floor with high water pressure. By the combination of physical and numerical modelling approaches, the variation characteristics of fracture development and volumetric strain of floor rocks subjected to mining disturbance are analyzed. A numerical computation model is constructed based on the volumetric strain-permeability equation obtained by curve fitting, and on such basis, the impacts of different mining parameters on floor rock permeability are studied. The results show that the floor rocks experience fracture generation, extension, and convergence procedures as the workface advances along the longitudinal direction, and fractures appearing in front of the workface are more developed. In the whole process of coal seam extraction, the volumetric strain profile exhibits “Λ” shape and an inverted saddle shape before and after overburden strata collapse. By controlling a single variable, the paper reveals that panel height is of greater impact on floor permeability changes than panel length and panel width.
APA, Harvard, Vancouver, ISO, and other styles
7

Smoliński, Adam, Krzysztof Stańczyk, Krzysztof Kapusta, and Natalia Howaniec. "Analysis of the organic contaminants in the condensate produced in the in situ underground coal gasification process." Water Science and Technology 67, no. 3 (2013): 644–50. http://dx.doi.org/10.2166/wst.2012.558.

Full text
Abstract:
Addressing the environmental risks related to contamination of groundwater with the phenolics, benzene, toluene, ethyl benzene, xylene (BTEX) and polycyclic aromatic hydrocarbons (PAHs), which might be potentially released from the underground coal gasification (UCG) under adverse hydrogeological and/or operational conditions, is crucial in terms of wider implementation of the process. The aim of this study was to determine the main organic pollutants present in the process condensate generated during the UCG trial performed on hard coal seam in the Experimental Mine ‘Barbara’, Poland; 8,933 L of condensate was produced in 813 h of experiment duration (including 456 h of the post-process stage) with average phenolics, BTEX and PAH concentrations of 576,000, 42.3 and 1,400.5 μg/L, respectively. The Hierarchical Clustering Analysis was used to explore the differences and similarities between the samples. The sample collected during the first 48 h of the process duration was characterized by the lowest phenanthrene, anthracene, fluoranthene and pyrene contents, high xylene content and the highest concentrations of phenolics, benzene, toluene and ethyl benzene. The samples collected during the stable operation of the UCG process were characterized by higher concentrations of naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)anthracene, chrysene, while in the samples acquired in the post-process stage the lowest concentrations of benzene, toluene, naphthalene, acenaphthene and fluorene were observed.
APA, Harvard, Vancouver, ISO, and other styles
8

Mironov, O. G. "Biological Problems of Oil Contamination of Seas." Hydrobiological Journal 37, no. 4 (2001): 16. http://dx.doi.org/10.1615/hydrobj.v37.i4.50.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

KUPLULU, O., G. IPLIKCIOGLU CIL, S. D. KORKMAZ, O. AYKUT, and G. OZANSOY. "Determination of Metal Contamination in Seafood from the Black, Marmara, Aegean and Mediterranean Sea Metal Contamination in Seafood." Journal of the Hellenic Veterinary Medical Society 69, no. 1 (2018): 749. http://dx.doi.org/10.12681/jhvms.16400.

Full text
Abstract:
Seafood is one of the most important components of a healthy diet due to its composition. With the Black, Marmara, Aegean and Mediterranean Sea, Turkey has substantial sources of seafood. Seas are highly impacted by environmental pollution. Among these, heavy metal pollution has long been recognized as a serious problem for seafood. As heavy metals cannot be degraded, they are deposited, assimilated or incorporated in water, sediment and aquatic animals. By these properties, they can be transferred to humans through the food chain especially by the consumption of fish and shellfish. The aim of this study is to determine the concentrations of Cd, As, Pb and Hg levels in selected fish species and marine animals from all of the 4 seas of Turkey by using the ICP-MS technique, and to compare the results with the legislations safe limits. For this purpose, 13 different fish species, mussels and shrimps have been obtained from the Black, Marmara, Aegean and Mediterranean Seas. According to the results, metal concentrations decrease in the order As>Pb>Hg>Cd. In all the seas, the same order was found. Statistically significant differences were observed in the metal levels between fish species and the shellfish in all regions. Except for the two samples, all the results was found compatible with the Turkish Food Codex and European Commission Regulation limits. Arsenic levels were detected between 0,076-4,230 mg/kg within the samples. Cadmium levels were detected as higher than the limits in two samples obtained from the Mediterranean Sea, Scophthalmus maximus and Mullus barbatus species as 0,076 mg/kg and 0,064 mg/kg, respectively. The highest and the lowest levels of mercury and lead were measured as 0,005-0,405 and 0,015-0,405 mg/kg, respectively. The results obtained from this study revealed that, except for a few cases, the selected heavy metal concentrations in most samples were below the limits. Also, besides the mussels and the shrimps, there was no single type of fish that was consistently high in all metals. The examined seas and the seafood were found to be safe for human consumption.
APA, Harvard, Vancouver, ISO, and other styles
10

Hildebrandt, Manuel, Corina Schwitzke, and Hans-Jörg Bauer. "Contamination of Brush Seals by Oil and Salt and Its Impact on Rubbing and Hysteresis Behaviour." International Journal of Turbomachinery, Propulsion and Power 4, no. 4 (2019): 40. http://dx.doi.org/10.3390/ijtpp4040040.

Full text
Abstract:
The literature already contains some experimental, analytical and numerical investigations on the rubbing and hysteresis behaviour of brush seals. What the investigations have in common is that they were carried out with new and uncontaminated seals, or that such a condition was assumed. The influence of contamination has not been explicitly investigated yet. Particularly in stationary gas and steam turbines, foreign substances can accumulate on and in the bristle package during steady-state operation. In the case of a rubbing event with a contaminated brush seal, e.g., during shutdown of the machine, the process is not expected to be comparable to that assumed in the presence of a new, uncontaminated seal. The present paper is dedicated to the question of the influence of contamination on the total frictional power loss generated during rubbing and the distribution of heat fluxes in friction contact. For this purpose, rub tests with two seals were carried out on the brush seal test rig of the Institute of Thermal Turbomachinery (ITS) in new conditions. Subsequently, the sealing packages were contaminated with oil or a salt mixture. After the treatment, the rub tests were repeated and compared with the previous tests. In addition, stiffness measurements were used to assess the degree of contamination. A strong influence on the rubbing behaviour by the contamination was detected. Contamination causes the flexibility of the bristle package to be greatly reduced. As a result, especially at the beginning of the first measurements, the total power losses and rotor heat inputs are strongly increased. This flexibility is partly regained in the course of the measurements. As expected, contamination also influences the hysteresis behaviour of the seal. A highly increased leakage rate after rubbing could be observed, because the bristles remained close to their deflected positions. In the case of the salted seal, however, an improvement in the leakage performance could be observed after several repeat tests.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Seam contamination"

1

Thürling, Karsten. "Prozessdatenanalyse zur Inline-Verminderung von Störeinflüssen beim Ultraschallsiegeln." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-214017.

Full text
Abstract:
Beim Siegeln von Verpackungen können nicht-qualitätsgerechte Siegelnähte dadurch entstehen, dass sich Teile des Packguts zwischen den zu fügenden Packmittelbahnen befinden. Im Gegensatz zum konventionellen Wärmekontaktsiegeln besteht beim Ultraschallsiegeln die Möglichkeit, für jeden einzelnen Siegelvorgang Prozessdaten zu erfassen. Aus dem Bereich des Ultraschallschweißens ist bekannt, dass sich anhand dieser Daten der Prozess überwachen und dessen Güte bewerten lässt. Die vorliegende Arbeit untersucht den Informationsgehalt dieser Prozessdaten hinsichtlich störungsbehafteter Siegelnähte und leistet damit einen Beitrag zur Verbesserung der Verpackungsqualität und damit im besten Fall auch zu weniger Lebensmittelverlusten. Es wird dazu zunächst eine Systematisierung von möglichen Störprinzipen beim Siegeln hinsichtlich ihrer physikalischen Wirkprinzipe vorgenommen. Darauf aufbauend konnte ein Versuchsstand und eine Methodik zur Untersuchung der Thematik entwickelt werden. Abschließend wurden ausgewählte Störprinzipe untersucht, wobei sich ein sehr starker Packstoff- und Einfluss der Prozessführung herausstellte. Es konnte ein prinzipieller Zusammenhang zwischen Auswirkung einer Störung auf die Nahtqualität und die Prozessdaten gezeigt werden, welcher sich jedoch auf Basis der erarbeiteten Ergebnisse nicht verallgemeinern lässt.
APA, Harvard, Vancouver, ISO, and other styles
2

Nyman, Madeleine. "Biomarkers for exposure and for the effects of contamination with polyhalogenated aromatic hydrocarbons in Baltic ringed and grey seals." Helsinki : University of Helsinki, 2000. http://ethesis.helsinki.fi/julkaisut/mat/ekolo/vk/nyman/.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Kortbaoui, Ziad S. "The sea shore contamination of the Lebanese coast /." Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=27537.

Full text
Abstract:
Sea water samples were collected from different sampling stations along the Lebanese coast in the summer of 1994. Chemical, biological and physical analysis were conducted to assess the recreational water quality in Lebanon.<br>Some 125 samples were then analyzed for the presence of Cadmium and Mercury by atomic absorption spectrophotometry. Cadmium content, holding a mean 0.77 $ mu$g/L, was generally low for most areas with only a few elevated readings in Tripoli (1.89 $ mu$g/L), Checca (1.83 $ mu$g/L), Kaslik (0.79 $ mu$g/L), Beirut (1.19 $ mu$g/L) and Ramlet Al-Bayda (1.77 $ mu$g/L). Mercury content, holding a mean value of 0.06 mg/Kg (wet weight), was below the accepted tolerance limit of 0.5 mg/Kg for all sampling sites.<br>Some 128 samples were then analyzed for fecal coliforms (Escherichia coli and Streptococcus feacalis). Approximately, 50% of the sampling stations showed satisfactory results (less than 100 colonies/100 ml). High counts of fecal coliforms, over 500 colonies/100 ml, collected at Dora, Ramlet Al-Bayda and Antelias, reveal poor sea water quality and a public health hazards to swimmers and fishermen.<br>Some 36 samples were collected and analyzed for dissolved oxygen (DO), pH, salinity and temperature. For all sites sampled, DO averaged 4.03 mg/L, pH averaged 7.97, salinity averaged 38.77 ppt and temperature averaged 27.9$ sp circ$C.<br>The degree of pollution was found to be related to population density, industrial and human activity, continental runoffs and hydrological and meteorological conditions.
APA, Harvard, Vancouver, ISO, and other styles
4

Kortbaoui, Ziad. "The sea shore contamination of the Lebanese coast." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ37136.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Hullinger, Weston Jay. "Mitigation of Sea Ice Contamination in QuikSCAT Wind Retrieval." BYU ScholarsArchive, 2012. https://scholarsarchive.byu.edu/etd/3412.

Full text
Abstract:
Satellite borne radar scatterometers provide frequent estimates of near surface wind vectors over the Earth's oceans. However in the polar oceans, the presence of sea ice in or near the measurement footprint can adversely a ect scatterometer measurements resulting in inaccurate wind estimates. Currently, such ice contamination is mitigated by discarding measurements within 50 km of detected sea ice. This approach is imperfect and causes loss of coverage. This thesis presents a new algorithm which detects ice-contaminated measurements based on a metric called the Ice Contribution Ratio (ICR) which measures the spatial ice contribution for each measurement. The ICR calculation is made for each measurement using a spatial ice probability map which is determined using Bayesian probability theory. Determined by simulation, the ICR processing thresholds the ICR for each measurement depending on local wind, ice backscatter, and cross-track location. ICR processing retrieves winds at a distance of 22.5 km from the ice edge on average, while ensuring wind accuracy. Retrieved wind distributions using ICR processing more closely resembles uncontaminated wind distributions than winds retrieved using previous methods. The algorithm is applied to QuikSCAT in this thesis but could be applied to other scatterometers such as the Oceansat-2 scatterometer.
APA, Harvard, Vancouver, ISO, and other styles
6

Al-Ghasem, Adnan Mahmoud. "Windback seal design for gas compressors: a numerical and experimental study." Texas A&M University, 2003. http://hdl.handle.net/1969.1/5740.

Full text
Abstract:
Seals are considered one of the important flow elements of a turbomachinery device. Traditional labyrinth seals have proven their performance functionality by reducing leakage rates. Significant improvements on labyrinth seal functionality were obtained through altering the design geometry of labyrinth seals to prevent contamination across a seal and maintaining small leakage flowrates. This results in a windback seal that has only one tooth which continuously winds around the shaft like a screw thread. These seals are used in gas compressors to isolate the gas face seal from bearing oil. A purge gas is passed through the seal into the bearing housing. The helical design allows the seal to clear itself of any oil contamination. Windback seal performance is controlled through changing the seal geometry. A 2D graphical design tool for calculating the total and cavity leakage flowrates for windback seals is introduced. The effectiveness of the Fluent CFD (Computational Fluid Dynamics) commercial code to accurately predict the leakage rate for windback seals was evaluated. The objective is to determine if CFD simulations can be used along with a few experimental tests to study windback seals of this design with air as the working fluid. Comparison of measurement and predictions for a windback seal using the κ-ε turbulence model with enhanced wall treatment functions show predictions and measurements comparing very well with a maximum difference of 5% for leakage rate. Similarly, the leakage rate of the tested smooth seal compares favorably with two dimensional CFD predictions, with a difference of 2%-11% and 8%-15% using laminar and κ-ε turbulent flow models, respectively. The variation of leakage with shaft speed and pressure ratio across the seals is accurately predicted by the CFD simulations. Increasing the rotor speed to 15000 rpm increases the measured leakage flowrate for the windback seal by 2% at high differential pressure and 4.5% at low differential pressure, and decreases it by 10 % for the smooth seal. The effects of seal clearance, tooth pitch, cavity depth and the tooth number of starts on leakage flowrate, velocity and pressure distributions were studied numerically for three differential pressures and four rotor speeds.
APA, Harvard, Vancouver, ISO, and other styles
7

Combi, Tatiane <1987&gt. "Contamination Trends of Legacy and Emerging Compounds in Sediments from the Adriatic Sea." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7476/.

Full text
Abstract:
Sediments are the final repositories for most pollutants, which can accumulate and remain in the sedimentary matrix for long periods of time and may accumulate through the food web, affecting marine biota, aquatic-dependent wildlife, and ultimately human health. Thus, a wide-ranging work monitoring different groups of contaminants in sediments is a key tool for a comprehensive understanding of contaminants behavior and identification of the overall environmental quality and possible threatens to the whole marine ecosystem. POPs, among which PCBs and DDTs rank first, polycyclic aromatic hyrocarbons (PAHs), and selected groups contaminants of emerging concern (CECs) (fragrances, UV filters, endocrine disruptors) were the objective of this work. First, PCB congeners were analyzed in sediment cores and recent sediments along the north-south axis of the western Adriatic Sea. Chronological records of PCB concentrations and homologue patterns were assessed, supporting the reconstruction of PCBs fluxes and total inventories. Then, the spatial distribution and fate of selected legacy and emerging compounds were investigated in surface sediments sampled along the Adriatic mud-wedge and in deep-sea regions from the southern Adriatic basin, providing the first extensive dataset and also the evaluation of potential ecotoxicological risk of target emerging contaminants in sediments from the Adriatic Sea. Finally, the analyzes of selected legacy contaminants (PCBs, DDTs and PAHs) in sediment cores from coastal and deep-sea sediments from the Adriatic Sea supported the comparison between these two areas and further reinforces the hypothesis on the transfer of contaminants from contaminated areas in the northern Adriatic to the deep southern Adriatic basin. The present thesis is the summary of the work carried out in the last three year of the PhD program “Scienze ambientali: tutela e gestione delle risorse naturali” and contains three manuscripts (two under review and one in preparation), and the main conclusions regarding this PhD research project.
APA, Harvard, Vancouver, ISO, and other styles
8

Delle, Cese Francesca. "EFFECT OF LIQUID CONTAMINATION ON HERMETICITY AND SEAL STRENGTH OF FLEXIBLE POUCHES WITH LLDPE SEALANT." DigitalCommons@CalPoly, 2014. https://digitalcommons.calpoly.edu/theses/1178.

Full text
Abstract:
Flexible packaging is a growing successful market and the majority of flexible package applications are for the food industry. The demand for process optimization and reduced production costs, has led to an increase in flexible packaging. However, fast production lines can result in contamination in the seal area. For flexible food packaging, contamination is considered any food particle or substance trapped in the seal area. Current quality control processes can detect contamination in the seal area, but it is not determined if seal contamination effects seal quality. Oil-based and sodium based snack foods are two common categories that can be packaged on a horizontal flow film and seal (HFFS) flow-wrap machine. The study uses vegetable oil and a salt water solution to simulate the effect of liquid contamination along the T-point of flexible pouches made on an HFFS. The T-point refers to where the fin seal meets the end seal and requires the seal jaw to seal through four layers of film, which is the most difficult point to seal. The study tests a combination of different sealing temperatures and dwell time to determine the optimal sealing condition for a hermetic seal. A quality hermetic seal provides an enclosed seal with no leaks due to successful polymer chain entanglement between the two sealant layers. The different test categories of the study are non-contaminated (control), salt water solution for salt based foods, and vegetable oil for oil-based foods. Given the test parameters of the study, 140⁰C sealing temperature and 0.3 seconds dwell time are considered to be the optimal sealing condition for all three test categories. For Phase 1 of the study, salt water has a lower hermeticity pass rate compared to vegetable oil and non-contaminated seals. In addition, the effect of refrigerated storage temperature and ambient storage temperature did not show to be significant for any of the test categories. However, refrigerated conditions showed a higher hermeticity pass rate, but it was not statistically different. The findings for seal strength indicated no test category had higher or lower seal strength over the 14 day test period. Overall, the study shows there is no effect of liquid contaminant on hermeticity and seal strength for flexible film with LLDPE sealant layer.
APA, Harvard, Vancouver, ISO, and other styles
9

PORTELLA, CRISTIANE MARIA DE MELLO ALVES. "EVALUATION OF THE POSSIBILITY OF CONTAMINATION OF SEA WATER BY METAL IONS PRESENT IN OIL." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2005. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=6942@1.

Full text
Abstract:
CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO<br>Com a probabilidade de ocorrer derrames de óleo em águas marinhas e a carência de informação sobre o comportamento de metais neste evento, viu-se a necessidade de se intensificar estudos referentes aos complexos metálicos, para que se possa entender a competição entre os ligantes do petróleo e os ligantes da água do mar. Para isto é necessário determinar a estabilidade dos complexos formados no petróleo, compará-los com os correspondentes na água do mar. Neste trabalho foram estudados os sistemas binários de complexos de ácido hexanóico (ligante que representa os ácidos carboxílicos do petróleo) e 1-propanotiol (representante das mercaptans) com os íons metálicos de interesse para a indústria do petróleo - Ni(II), V(IV) e Fe(II) - por estarem presentes em maior quantidade. Embora presentes em menor quantidade, Cd(II) e Pb(II) foram estudados por serem metais tóxicos e controlados pelas organizações ambientais. O ácido hexanóico apresenta o oxigênio do grupamento carboxilato, como sítio de coordenação enquanto que o 1-propanotiol possui o enxofre do grupamento tiol. O estudo da complexação foi realizado em solução utilizando a titulação potenciométrica e a espectrofotometria de ultravioleta- visível, Foram calculadas as constantes de dissociação dos ligantes e de formação dos complexos ML, ML2, ML3, MLOH, ML(OH)2, ML(OH)3, ML2OH, ML2(OH)2, ML3OH. Os valores das constantes de estabilidade dos complexos poderiam ser divididos em dois grupos: o dos complexos binários com ácido hexanóico e os complexos binários do 1- propanotiol. Dos complexos formados com o ácido hexanóico, a espécie ML com o íon metálico Pb(II) foi que apresentou maior estabilidade. No sistema onde temse complexos com 1-propanotiol, a espécie ML do íon metálico Cd(II) foi o que apresentou maior estabilidade. Na distribuição de espécies com ligantes representantes do petróleo e ligantes da água do mar observou-se a formação de complexos em pH = 7 para os íon metálicos V(IV), Ni(II) e Fe(II) com o ácido hexanóico. Para o íon metálico Pb(II) o complexo formado foi com o 1- propanotiol. Já para o íon Cd(II) houve a formação de complexo com o cloreto. Para o íon Cd(II), neste pH houve formação de pouca proporção de complexos com 1-propanotiol e um percentual maior (60 por cento) de complexos com os íons cloreto e sulfato da água do mar. Entretanto, como a concentração de cádmio é em torno de ppb no óleo combustível, este valor tem pouca relevância em termos de poluição. Assim, se estes ligantes estudados, que são monodentados, ligam-se preferencialmente aos metais do que os ligantes da água, com certeza isto acontece com os ligantes polidentados do petróleo como por exemplo as porfirinas. Com a utilização da técnica de espectrofotometria de ultravioletavisível foi possível observar as bandas referentes a transferência de carga e banda d-d. Foi realizada também uma simulação de derrame de óleo combustível. Para isto analisou-se a concentração de metais foi medida em tempos variados. Os dados teóricos e da simulação confirmam que íons metálicos ficam retidos no óleo mesmo quando há derrame do óleo na água do mar.<br>In face of the probability of occurrences of oil spill in marine waters and the lack of information concerning the behavior of the metals in such events, it is necessary to intensify the studies of metal complexes in order to understand the competition between oil ligands and sea water ligands. For such, it is necessary to determine the stability of the complexes formed in oil and compare them with the correspondent ones in sea water. In the present work the binary systems of the complexes of hexanoic acid (a ligand that represents the carboxylic acids of the oil) and 1-propanethiol (which represents the mercaptans) with the metal ions of interest to the petroleum industry - Ni(II), V(IV) and Fe (II) - were studied because they are present in greater quantities. Despite being present in smaller quantities, Cd(II) and Pb(II) were also studied because they are toxic and controlled by environmental organizations. Hexanoic acid has an oxygen atom of the carboxylate group as donor atom, and 1-propanethiol has a sulfur atom of the thiol group. The complexation study was performed in solution using potentiometric titration and ultraviolet-visible spectrophotometry. The dissociation constants of the ligands and the formation constants of the complex species ML, ML2, ML3, MLOH, ML(OH)2, ML(OH)3, ML2OH, ML2 (OH)2 and ML3(OH) were calculated. The values of the stability constants can be divided in two groups: one with the binary complexes of hexanoic acid and the other with the binary complexes of 1-propanethiol. Among the complexes formed with hexanoic acid, the ML species with metal ion Pb(II) was the most stable. In the system of the complexes with 1-propanethiol, the ML species with Cd(II) was the most stable. In the species distribution as a function of pH including the representative ligands of oil and sea water, it could be observed that at pH =7 the most stable species for the metal ions V(IV), Ni(II) and Fe (II) were those with hexanoic acid. In relation to ion Pb(II) the complex formed was with 1- propanethiol. Cd(II), this pH occurred the formation of a small proportion of the complex with 1-propanethiol and a higher percentual (60 percent) of the complexes with the chloride and sulfate íons of sea water. Since the concentration of Cd(II) is in the range of ppb, this metal ion is less relevant when pollution is concerned. Thus, if the monodentate oil ligands studied in this work preferably bind metal ions rather than sea water ligands, than this certainly happens with the polydentate oil ligands such as porphyrins. Using the ultraviolet-visible spectrophotometry technique it was possible to observe the charge transfer bands and the d-d bands. A simulation of oil dispersion was also performed and the concentration of the metals was measured at various times. Both theoretical and simulation data showed that the metal ions are retained in the oil, even when the oil is spread in sea water.
APA, Harvard, Vancouver, ISO, and other styles
10

St-Germain, Pascale L. "Evaluation of Well Seal Integrity and Its Relative Importance in Assessing Groundwater Quality." Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20446.

Full text
Abstract:
Unlike municipal water supplies, provincial regulations do not require systematic testing of domestic well water, which may adversely impact local residents should contamination occur. Private wells are typically shallow relative to municipal wells, and thus, are particularly vulnerable to sources of surficial contamination if preferential recharge pathways such as natural fractures or faulty seals are present. In order to determine the relative importance of well seal integrity as a preferential pathway, a practical detection method was developed based on infiltrometry. This method successfully detected faulty well seals in a wide range of geological settings across Canada, including: Hobbema, Alberta; Lindsay, Ontario; and Chelsea, Québec. It was most successful in areas of minimal heterogeneity and where the surficial geology is composed of fine-grained sediments. The community of Chelsea (Québec) was also the primary study site to examine a range of factors affecting water quality including physical characteristics, faulty well seals, other anthropogenic activities and seasonality. Water samples were collected over a period of 14 months and analyzed for bacteria and major-ion chemistry. The results show that the consideration of physical features alone is not enough to predict vulnerability in the study area. Seasonal fluctuations in ionic concentrations (e.g. ionic strength, NO3-N and Cl-) and coliform bacteria are observed and result from disperse and rapid recharge events. Multivariate analysis techniques (e.g. principal components analysis and hierarchical cluster analysis) demonstrate that preferential recharge pathways and anthropogenic activities, such as domestic effluents affect the groundwater quality. The data and findings of this study were used to assist in the design of a probabilistic risk assessment model based on the Poisson distribution. This study demonstrates the complexity and the challenges related to bacterial contamination in drilled wells. In spite of these challenges, this analysis was useful as a baseline to assess the impact of anthropogenic activities, and may be used in future studies to assist municipalities in the evaluation and protection of groundwater supplies.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Books on the topic "Seam contamination"

1

Politzer, Ieva R. Impact on human health of petroleum in the marine environment. The Institute, 1985.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
2

S, Ginn Jon, ed. Practical handbook of soil, vadose zone, and ground-water contamination: Assessment, prevention, and remediation. 2nd ed. Lewis Publishers, 2004.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
3

Practical handbook of soil, vadose zone, and ground-water contamination: Assessment, prevention, and remediation. Lewis Publishers, 1995.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
4

Nuclear contamination in the Arctic Ocean: Hearing before the Subcommittee on Oceanography, Gulf of Mexico, and the Outer Continental Shelf of the Committee on Merchant Marine and Fisheries, House of Representatives, One Hundred Third Congress, first session, on addressing the problem of extensive dumping of radioactive waste in the Arctic Ocean, September 30, 1993. U.S. G.P.O., 1993.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
5

Mærli, Morten Bremer. Strengthening cooperative threat reduction with Russia: The Norwegian experience. Norwegian Institute of International Affairs, 2002.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
6

Frid, Christopher L. J., and Bryony A. Caswell. Introduction to marine pollution. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198726289.003.0001.

Full text
Abstract:
It is universally agreed that pollution is a bad thing but quite what is meant by this is not clear. This chapter considers the formal definition of the word and distinguishes pollution, which has an impact on the environment and human activities, from contamination, which is merely the presence of substances at raised concentrations. It examines the history of marine pollution and how this has stimulated science, technical developments to treat wastes and the regulation and management of potentially polluting activities. Humankind has been putting waste into the sea for as long as people have lived at the coast. The growth of human populations increased the scale of the problem while industrialisation and the development of new materials have expanded the range of substances that enter the sea. Given this long history of regulation, scientific study and technical development, can marine pollution be considered a solved problem?
APA, Harvard, Vancouver, ISO, and other styles
7

Baker, Maria, Eva Ramirez-Llodra, and Paul Tyler, eds. Natural Capital and Exploitation of the Deep Ocean. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780198841654.001.0001.

Full text
Abstract:
The deep ocean is, by far, the planet’s largest biome and holds a wealth of potential natural assets. Most of the ocean lies beyond national jurisdiction and hence is the responsibility of us all. Human exploitation of the deep ocean is rapidly increasing, becoming more visible to many through the popular media. The scientific literature of deep-sea exploitation and its actual and potential effects has also rapidly expanded as a direct function of this increased national and global interest in deep-sea resources, both biological (e.g. fisheries, genetic resources) and non-biological (e.g. minerals, oil, gas, methane hydrate). At the same time there is a growing interest in deep-sea contamination (including plastics), with many such studies featured in high-profile scientific journals and covered by global media outlets. Finally, climate change is affecting even the deepest regions of our oceans and is a major priority for the international scientific and political agendas. However, there is currently no comprehensive integration of information about resource extraction, pollution and effects of climate change and these topics are only superficially covered in classic textbooks on deep-sea biology. The human race is at a pivotal point in potentially benefitting from the deep ocean’s natural resources and this concise and accessible work provides an account of past explorations and exploitations of the deep ocean, a present understanding of its natural capital and how this may be exploited sustainably for the benefit of humankind whilst maintaining its ecological integrity. The book gives a comprehensive account of geological and physical processes, ecology and biology, exploitation, management, and conservation.
APA, Harvard, Vancouver, ISO, and other styles
8

Boulding, J. Russell, and Jon S. Ginn. Practical Handbook of Soil, Vadose Zone, and Ground-Water Contamination: Assessment, Prevention, and Remediation, Secon. 2nd ed. CRC, 2003.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
9

Boulding, J. Russell, and Jon S. Ginn. Practical Handbook of Soil, Vadose Zone, and Ground-Water Contamination: Assessment, Prevention, and Remediation, Second Edition. Taylor & Francis Group, 2016.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
10

Nuclear contamination in the Arctic Ocean: Hearing before the Subcommittee on Oceanography, Gulf of Mexico, and the Outer Continental Shelf of the Committee on Merchant Marine and Fisheries, House of Representatives, One Hundred Third Congress, first session, on addressing the problem of extensive dumping of radioactive waste in the Arctic Ocean, September 30, 1993. U.S. G.P.O., 1994.

Find full text
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Seam contamination"

1

Yufit, Sergey S., Igor V. Miskevich, and Olga N. Shtemberg. "Chemical Weapons Dumping and White Sea Contamination." In Sea-Dumped Chemical Weapons: Aspects, Problems and Solutions. Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-015-8713-6_17.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Kunito, Takashi, Reiji Kubota, Junko Fujihara, Tetsuro Agusa, and Shinsuke Tanabe. "Arsenic in Marine Mammals, Seabirds, and Sea Turtles." In Reviews of Environmental Contamination and Toxicology. Springer New York, 2008. http://dx.doi.org/10.1007/978-0-387-77030-7_2.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Botello, Alfonso V., F. Susana Villanueva, and G. Gilberto Diaz. "Petroleum Pollution in the Gulf of Mexico and Caribbean Sea." In Reviews of Environmental Contamination and Toxicology. Springer New York, 1997. http://dx.doi.org/10.1007/978-1-4612-2302-3_3.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Walraven, N., and R. W. P. M. Laane. "Assessing the Discharge of Pharmaceuticals Along the Dutch Coast of the North Sea." In Reviews of Environmental Contamination and Toxicology. Springer US, 2008. http://dx.doi.org/10.1007/978-0-387-09808-1_1.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Kot-Wasik, Agata, Barbara Żukowska, Dagmara Dąbrowska, Jolanta Dębska, Józef Pacyna, and Jacek Namieśnik. "Physical, Chemical, and Biological Changes in the Gulf of Gdańsk Ecosystem (Southern Baltic Sea)." In Reviews of Environmental Contamination and Toxicology. Springer New York, 2003. http://dx.doi.org/10.1007/0-387-21731-2_1.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Pavlov, V. K., V. V. Stanovoy, and A. I. Nikitin. "Possible Causes of Radioactive Contamination in the Laptev Sea." In Land-Ocean Systems in the Siberian Arctic. Springer Berlin Heidelberg, 1999. http://dx.doi.org/10.1007/978-3-642-60134-7_8.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Siegel, Frederic R. "Arresting/Controlling Saltwater Contamination of Coastal Aquifers." In Adaptations of Coastal Cities to Global Warming, Sea Level Rise, Climate Change and Endemic Hazards. Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-22669-5_2.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Sheikholeslami, Mohammad Reza, Vladimir Vladymyrov, and Stephen de Mora. "Contamination of the Caspian Sea: An Overview on Recent Findings." In NATO Science Series: IV: Earth and Environmental Sciences. Springer Netherlands, 2004. http://dx.doi.org/10.1007/978-94-007-0967-6_9.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Tammemäe, Olavi. "Remediation of Polluted Environment at Naval Ports of the Baltic Sea." In Environmental Contamination and Remediation Practices at Former and Present Military Bases. Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-011-5304-1_25.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Mitrovica, Jerry X., Mark E. Tamisiea, Erik R. Ivins, L. L. A. Bert Vermeersen, Glenn A. Milne, and Kurt Lambeck. "Surface Mass Loading on a Dynamic Earth: Complexity and Contamination in the Geodetic Analysis of Global Sea-Level Trends." In Understanding Sea-Level Rise and Variability. Wiley-Blackwell, 2010. http://dx.doi.org/10.1002/9781444323276.ch10.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Seam contamination"

1

Uptigrove, Stan O., Paul S. Eakins, and John E. Sears. "Dry Gas Seal Developments and Contamination Prevention." In 1996 1st International Pipeline Conference. American Society of Mechanical Engineers, 1996. http://dx.doi.org/10.1115/ipc1996-1896.

Full text
Abstract:
Dry gas seals have become the pipeline industry standard for sealing of centrifugal gas compression equipment. Recent applications have pushed the limits of materials used in their construction from exposure to ever increasing levels of pressure, speed and temperature. This provides the focus for a discussion of recent advances with the use of advanced materials, higher pressure, speed and temperature applications and bidirectional designs. Operating experience has been very favourable, enough to make dry gas seals a preferred standard, but the failures that have occurred raise two fundamental questions. The first concerns the resistance of gas seals to contamination and the second is their influence upon rotor dynamic behavior. Both of these predominant issues are reviewed along with advancements and preventive measures now available to address these concerns.
APA, Harvard, Vancouver, ISO, and other styles
2

Gao, Yibo, Benxin Wu, Ze Liu, and Yun Zhou. "Ultrasonic Cavitation Peening of Stainless Steel and Nickel Alloy." In ASME 2013 International Manufacturing Science and Engineering Conference collocated with the 41st North American Manufacturing Research Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/msec2013-1236.

Full text
Abstract:
Ultrasonic cavitation peening is a peening process utilizing the high pressure induced by ultrasonic cavitation in liquids (typically water). However, the relevant previous investigations in the literature have been limited. In this paper, ultrasonic cavitation peening on stainless steel and nickel alloy has been studied, including the observation or characterization of the surface hardness, morphology, profile, roughness and oxygen contamination of treated workpiece samples. It has been found that for the studied situations, ultrasonic cavitation peening (at a sufficiently high horn vibration amplitude) can obviously enhance the workpiece surface hardness without significantly increasing the surface roughness, changing surface morphology observed by scanning electron microscope (SEM), or contaminating the surface by oxygen.
APA, Harvard, Vancouver, ISO, and other styles
3

Corbella, Ignasi, Israel Duran, Wu Lin, et al. "Mitigation of land-sea contamination in SMOS." In IGARSS 2015 - 2015 IEEE International Geoscience and Remote Sensing Symposium. IEEE, 2015. http://dx.doi.org/10.1109/igarss.2015.7326047.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Tao, Ding, Anthony P. Doulgeris, and Camilla Brekke. "Sea clutter contamination test with log-cumulants." In SPIE Remote Sensing, edited by Claudia Notarnicola, Simonetta Paloscia, and Nazzareno Pierdicca. SPIE, 2012. http://dx.doi.org/10.1117/12.976879.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Brown, Clifford A., and Nicholas A. Schifer. "Low Frequency Noise Contamination in Fan Model Testing." In ASME Turbo Expo 2008: Power for Land, Sea, and Air. ASMEDC, 2008. http://dx.doi.org/10.1115/gt2008-50850.

Full text
Abstract:
Aircraft engine noise research and development depends on the ability to study and predict the noise created by each engine component in isolation. The presence of a downstream pylon for a model fan test, however, may result in noise contamination through pylon interactions with the free stream and model exhaust airflows. Additionally, there is the problem of separating the fan and jet noise components generated by the model fan. A methodology was therefore developed to improve the data quality for the 9 × 15 Low Speed Wind Tunnel (LSWT) at the NASA Glenn Research Center that identifies three noise sources: fan noise, jet noise, and rig noise. The jet noise and rig noise were then measured by mounting a scale model of the 9 × 15 LSWT model fan installation in a jet rig to simulate everything except the rotating machinery and in duct components of fan noise. The data showed that the spectra measured in the LSWT has a strong rig noise component at frequencies as high as 3 kHz depending on the fan and airflow fan exit velocity. The jet noise was determined to be significantly lower than the rig noise (i.e. noise generated by flow interaction with the downstream support pylon). A mathematical model for the rig noise was then developed using a multi-dimensional least squares fit to the rig noise data. This allows the rig noise to be subtracted or removed, depending on the amplitude of the rig noise relative to the fan noise, at any given frequency, observer angle, or nozzle pressure ratio. The impact of isolating the fan noise with this method on spectra, overall power level (OAPWL), and Effective Perceived Noise Level (EPNL) is studied.
APA, Harvard, Vancouver, ISO, and other styles
6

Cardwell, D. N., K. S. Chana, and P. Russhard. "The Use of Eddy Current Sensors for the Measurement of Rotor Blade Tip Timing: Sensor Development and Engine Testing." In ASME Turbo Expo 2008: Power for Land, Sea, and Air. ASMEDC, 2008. http://dx.doi.org/10.1115/gt2008-50792.

Full text
Abstract:
The advent of tip-timing systems makes it possible to assess turbomachinery blade vibration using non-contact systems. Currently, the most widely used systems in industry are optical systems. However, these systems are still only used on development engines, largely because of contamination problems from dust, dirt, oil, water etc. Further development of these systems for in-service use is problematic because of the difficulty of eliminating contamination of the optics. Hence, alternatives need to be developed that are immune to contamination but have equivalent resolution and bandwidth as the optical system. Experimental measurements have been carried out using alternative sensors. An eddy current sensor has been developed in a series of laboratory and engine tests to measure rotor blade arrival times. Comparisons are made with an industry standard optical blade tip timing system. The results show that it is possible to acquire high quality blade tip timing data for use in engine condition monitoring using an eddy current sensor. This sensor allows measurements to be taken that do not suffer from flow contamination and allow deployment for hotter flow environments.
APA, Harvard, Vancouver, ISO, and other styles
7

Alkhaled, Makram, Emad Alsusa, Ammar Hadi, and Abdurrahman Alfitouri. "Pilot contamination mitigation in TDD massive MIMO systems." In 2017 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom). IEEE, 2017. http://dx.doi.org/10.1109/blackseacom.2017.8277658.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Kasprowicz, Bryan S., Mohan Ananth, and Chih-Yu Wang. "Investigating inspectability and printability of contamination deposited during SEM analysis." In Photomask Technology, edited by Brian J. Grenon and Giang T. Dao. SPIE, 2001. http://dx.doi.org/10.1117/12.410674.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Corral, Roque, and David del Campo. "Effect of Sidewall Contamination on Linear Cascades With Moving Bars." In ASME Turbo Expo 2005: Power for Land, Sea, and Air. ASMEDC, 2005. http://dx.doi.org/10.1115/gt2005-68176.

Full text
Abstract:
The effect of the nite extent of linear cascades on the unsteady pressure distribution due to the presence of moving bars is assessed by means of a numerical study. The height of a reference cascade made up of at plates has been changed to quantify its in uence. It is concluded that seven blades are enough to get rid of the contamination associated to the lateral walls of the cascade on the modulus of the unsteady pressure and that the resonant conditions of the cascade shall be avoided to improve its periodicity. The sidewall interference has been also studied for a representative low pressure turbine airfoil without signicantly modifying the conclusions obtained using at plates. The mode decomposition at the cascade exit shows also a reasonable matching with the periodic case.
APA, Harvard, Vancouver, ISO, and other styles
10

Yeung, Yip Fun, Emily Genevriere, and Kamal Youcef-Toumi. "Design of a Mechanical Sealing Device for Robotic Water Distribution Pipe Rehabilitation." In ASME 2020 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/imece2020-23048.

Full text
Abstract:
Abstract Water distribution pipe maintenance is a global concern. In this study, we propose a Rehabilitation In-Pipe Robot (R-IPR) to perform pipe rehabilitation operations and contain induced contamination. The robot features three modules: a pipe cleaning module, a mechanical sealing module, and an in-pipe manipulator module. This study emphasizes the comprehensive design of the mechanical sealing module. We introduce a multi-layer compound structure of the seal to deal with two characteristics of tuberculated pipe surfaces: 1. macroscopical surface roughness, 2. overhang in foundation profile. The prototype excels in sealing foundation overhang and requires 45% lower compression load than a baseline seal to function. The prototype seal is integrated into the R-IPR. Finally, experiments of the overall system demonstrate the successful performance of the first contamination-less in-pipe rehabilitation.
APA, Harvard, Vancouver, ISO, and other styles

Reports on the topic "Seam contamination"

1

Bradley, D. J. Radioactive contamination of the Arctic Region, Baltic Sea, and the Sea of Japan from activities in the former Soviet Union. Office of Scientific and Technical Information (OSTI), 1992. http://dx.doi.org/10.2172/10102627.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Bradley, D. J. Radioactive contamination of the Arctic Region, Baltic Sea, and the Sea of Japan from activities in the former Soviet Union. Office of Scientific and Technical Information (OSTI), 1992. http://dx.doi.org/10.2172/6821704.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Hardy, J. T., and C. E. Cowan. Model and assessment of the contribution of dredged material disposal to sea-surface contamination in Puget Sound. Office of Scientific and Technical Information (OSTI), 1986. http://dx.doi.org/10.2172/6063339.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Health hazard evaluation report: sea lamprey pesticide contamination at a biological station. U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, 2013. http://dx.doi.org/10.26616/nioshheta201201643174.

Full text
APA, Harvard, Vancouver, ISO, and other styles
You might also be interested in the extended bibliographies on the topic 'Seam contamination' for particular source types:
Journal articles Dissertations / Theses
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography