WorldWideScience

Sample records for secondary hydrocarbon migration

  1. Finite Volume Method for Solving a Modified 3-D 3-Phase Black-Oil Hydrocarbon Secondary Migration Model, and Its Application to the Kuqa Depression of the Tarim Basin in Western China

    OpenAIRE

    Guangren SHI; MA Jinshan; YANG Xinshe; CHANG Junhua; WAN, JUN

    2011-01-01

    By using a finite volume method as a solver, a modified 3-D 3-phase (water, oil, gas) black-oil model for modeling hydrocarbon (HC) secondary migration in the context of basin modeling is presented in this paper. The model predicts the quantity and distribution of HC accumulation in space and time. The black-oil model used in basin modeling is more complex and more difficult to model than that in reservoir simulations, as the model includes variable simulation ranges, very long simul...

  2. The pulsed migration of hydrocarbons across inactive faults

    Directory of Open Access Journals (Sweden)

    S. D. Harris

    1999-01-01

    Full Text Available Geological fault zones are usually assumed to influence hydrocarbon migration either as high permeability zones which allow enhanced along- or across-fault flow or as barriers to the flow. An additional important migration process inducing along- or across-fault migration can be associated with dynamic pressure gradients. Such pressure gradients can be created by earthquake activity and are suggested here to allow migration along or across inactive faults which 'feel' the quake-related pressure changes; i.e. the migration barriers can be removed on inactive faults when activity takes place on an adjacent fault. In other words, a seal is viewed as a temporary retardation barrier which leaks when a fault related fluid pressure event enhances the buoyancy force and allows the entry pressure to be exceeded. This is in contrast to the usual model where a seal leaks because an increase in hydrocarbon column height raises the buoyancy force above the entry pressure of the fault rock. Under the new model hydrocarbons may migrate across the inactive fault zone for some time period during the earthquake cycle. Numerical models of this process are presented to demonstrate the impact of this mechanism and its role in filling traps bounded by sealed faults.

  3. Hydrocarbon migration and accumulation in the Upper Cretaceous Qingshankou Formation, Changling Sag, southern Songliao Basin: Insights from integrated analyses of fluid inclusion, oil source correlation and basin modelling

    Science.gov (United States)

    Dong, Tian; He, Sheng; Wang, Dexi; Hou, Yuguang

    2014-08-01

    The Upper Cretaceous Qingshankou Formation acts as both the source and reservoir sequence in the Changling Sag, situated in the southern end of the Songliao Basin, northeast China. An integrated approach involving determination of hydrocarbon charging history, oil source correlation and hydrocarbon generation dynamic modeling was used to investigate hydrocarbon migration processes and further predict the favorable targets of hydrocarbon accumulations in the Qingshankou Formation. The hydrocarbon generation and charge history was investigated using fluid inclusion analysis, in combination with stratigraphic burial and thermal modeling. The source rocks began to generate hydrocarbons at around 82 Ma and the hydrocarbon charge event occurred from approximately 78 Ma to the end of Cretaceous (65.5 Ma) when a large tectonic uplift took place. Correlation of stable carbon isotopes of oils and extracts of source rocks indicates that oil was generated mainly from the first member of Qingshankou Formation (K2qn1), suggesting that hydrocarbon may have migrated vertically. Three dimensional (3D) petroleum system modeling was used to evaluate the processes of secondary hydrocarbon migration in the Qingshankou Formation since the latest Cretaceous. During the Late Cretaceous, hydrocarbon, mainly originated from the Qianan depression, migrated laterally to adjacent structural highs. Subsequent tectonic inversion, defined as the late Yanshan Orogeny, significantly changed hydrocarbon migration patterns, probably causing redistribution of primary hydrocarbon reservoirs. In the Tertiary, the Heidimiao depression was buried much deeper than the Qianan depression and became the main source kitchen. Hydrocarbon migration was primarily controlled by fluid potential and generally migrated from relatively high potential areas to low potential areas. Structural highs and lithologic transitions are potential traps for current oil and gas exploration. Finally, several preferred hydrocarbon accumulation sites have been identified by this work, like Western Slope, Southern uplift, and Eastern Slope, helping reduce the risk on targeting hydrocarbon potential reservoirs in Changling Sag.

  4. Migration of selected hydrocarbon contaminants into dry pasta packaged in direct contact with recycled paperboard.

    Science.gov (United States)

    Barp, Laura; Suman, Michele; Lambertini, Francesca; Moret, Sabrina

    2015-01-01

    This paper deals with the migration of selected hydrocarbon contaminants, namely mineral oil hydrocarbons (MOH), diisopropyl naphthalenes (DIPN) and polyalphaolefins (PAO) from adhesives into dry semolina and egg pasta packaged in direct contact with recycled paperboard. Migration was monitored during its shelf life (for up to two years) simulating storage in a supermarket (packs on shelves) and conditions preventing exchange with the surrounding environment (packs wrapped in aluminium foil). Migration from the secondary packaging (transport boxes of corrugated board) was also studied for semolina pasta. After 24 months of exposure, semolina pasta stored on shelves reached 3.2 and 0.6 mg kg(-1) of MOSH and MOAH, respectively, Migration from the adhesives used to close the boxes and from the transport boxes contributed about 30% and 25% of the total contamination, respectively. The highest contamination levels (14.5 and 2.0 mg kg(-1) of MOSH and MOAH, respectively, after 24 months) were found in egg pasta stored on shelves (no adhesives), and seemed due to the highest contribution from the external environment. PMID:25571955

  5. Arsenic cycling in hydrocarbon plumes: secondary effects of natural attenuation

    Science.gov (United States)

    Cozzarelli, Isabelle M.; Schreiber, Madeline E.; Erickson, Melinda L.; Ziegler, Brady A.

    2015-01-01

    Monitored natural attenuation is widely applied as a remediation strategy at hydrocarbon spill sites. Natural attenuation relies on biodegradation of hydrocarbons coupled with reduction of electron acceptors, including solid phase ferric iron (Fe(III)). Because arsenic (As) adsorbs to Fe-hydroxides, a potential secondary effect of natural attenuation of hydrocarbons coupled with Fe(III) reduction is a release of naturally occurring As to groundwater. At a crude-oil-contaminated aquifer near Bemidji, Minnesota, anaerobic biodegradation of hydrocarbons coupled to Fe(III) reduction has been well documented. We collected groundwater samples at the site annually from 2009 to 2013 to examine if As is released to groundwater and, if so, to document relationships between As and Fe inside and outside of the dissolved hydrocarbon plume. Arsenic concentrations in groundwater in the plume reached 230?µg/L, whereas groundwater outside the plume contained less than 5?µg/L As. Combined with previous data from the Bemidji site, our results suggest that (1) naturally occurring As is associated with Fe-hydroxides present in the glacially derived aquifer sediments; (2) introduction of hydrocarbons results in reduction of Fe-hydroxides, releasing As and Fe to groundwater; (3) at the leading edge of the plume, As and Fe are removed from groundwater and retained on sediments; and (4) downgradient from the plume, patterns of As and Fe in groundwater are similar to background. We develop a conceptual model of secondary As release due to natural attenuation of hydrocarbons that can be applied to other sites where an influx of biodegradable organic carbon promotes Fe(III) reduction.

  6. From places to flows. International secondary migration and birth outcomes.

    Science.gov (United States)

    Urquia, Marcelo L; Frank, John W; Glazier, Richard H

    2010-11-01

    Research on the health status of international migrants to industrialised countries in general, and on perinatal outcomes in particular, has assumed an interpretative model based on primary migration, characterised by one permanent cross-border movement from the migrant's country of birth. However, many migrants experience more complex migration patterns that may also be associated with human health. Secondary migration, defined as a migration from a country of residence other than the country where the immigrant was born, has been growing during the last two decades, favoured by globalisation. The purpose of this study was to examine the association between secondary migration and preterm birth (PTB) and infant birthweight at term (BW) using a Canadian official immigration database to build a cohort of immigrants to Ontario, Canada, who obtained their permanent residence in the years 1985-2000. The study population comprised 320,398 singleton live infants born to immigrant women during 1988-2007. Primary and secondary migrants were categorised according to whether they were born in an industrialised country or not. Secondary migrants were further subdivided according to whether the country from which they migrated to Canada was industrialised or not. We found that compared to primary migrants, secondary migrants to Canada born in non-industrialised countries had lower odds of PTB and higher mean BW at term. However, such a protective effect was not observed among secondary migrants born in industrialised countries. In a cross-classified multilevel model restricted to secondary migrants, 5.2% of the variation in birthweight was explained by migrants' countries of birth and 0.8% by migrants' countries of last permanent residence. These findings are consistent with the so-called healthy migrant effect, implying that selective migration from non-industrialised countries is associated with protective individual characteristics. PMID:20850920

  7. Migration of hydrocarbons in the subsoil of an industrial installation

    International Nuclear Information System (INIS)

    The fate of old industrial sites is a major problem at the beginning of the new millennium for government organization, agencies owning polluted sites... These brown-field sites often generate considerable pollution of soils and groundwater, the main source of drinking water. The National Center for Research on Polluted Soils and Sites (CNRSSP), in which the CEA is an active partner, is developing a strategy to study and, using several scientific tools, characterize industrial sites polluted by various contaminants: metals, metalloids, hydrocarbons, nitrates. The present study offers an example of the investigation of an old industrial site (coke plant), built in 1919 (in operation for 50 years), located in northern France. The storage of tars and wastewaters on these sites causes soil and groundwater contamination with organic compounds such as Polycyclic Aromatic Hydrocarbons (PAHs), mono-aromatic hydrocarbons (benzene, toluene, ethyl-benzene and xylene BTEX), volatile organic compounds (VOCs), phenolic and other hydrocarbons, and inorganic compounds including metalloids (free and complexed cyanides) and metals (As, Pb, Ni, Cd and Hg). The more soluble constituents tend to migrate to adjacent areas with the groundwater flow and thereby reach receptors such as drinking water resources. Among the above pollutants, the 16 PAHs from the priority list of the Environmental Protection Agency (EPA) are of great environmental concern due to their toxic, mutagenic and carcinogenic properties. The remediation of PAH-polluted sites poses a crucial challenge given the large number of sites contaminated by these pollutants and the difficulty in eliminating the pollution. A better evaluation of the PAH transfer and transport in soils and aquifers will also help draw up remediation strategies. In this study, a numerical model, called SIMUSCOPP and developed by the French Petroleum Institute (IFP), BURGEAP and ENI group for organic pollutants, was used to simulate 3D transfer and transport of PAHs under an old coke plant, taking biodegradation and soil sorption into account. The simulation results discussed in this paper were obtained by assuming tar pollution 7 m deep underground to be the only source. This aquifer pollution in a chalky formation mainly consists of PAHs (naphthalene, fluoranthene, etc). A broad field investigation was conducted on the site by monitoring the water (16 piezometers, piezometric measurements, pollutant concentration analysis) to characterize the location and extent of the PAH plume. The numerical modeling was aimed to characterize PAH migration in the unsaturated and saturated zones and to assess the vulnerability of a drinking water well located downstream. The model helped estimate the time for dissolved naphthalene to reach steady state (20 years) and the plume dimensions (1200 m long, 300 m wide and 15 m thick). Simulation were performed of water samplings in piezometers inside and outside the polluted area and the naphthalene concentration in water samples was reproduced, in good agreement with real observations on boreholes of the site. However, for two piezometers located between the two lagoons of coal tars, a large contribution of a second source of PAH, enriched in PAHs with 2 or 3 rings and located at the base of aquifer, was identified in water samples, in the pumped water. This significant share of the pollution is not transported with groundwater flow, but only with water pumping. Thus SIMUSCOPP served to identify the dissolved phase of PAH and to quantify the rest of the pollution, possibly a colloidal phase. As a consequence, a new water sampling strategy could be developed in order to adjust the pump discharge, use specific filters, etc. The major conclusion of the transport simulation is that the PAH plume does not reach the drinking water well located 4 km downstream of the site. However, some remediation measures are necessary and the polluted soils are currently being excavated. (author)

  8. Hydrocarbon solubility and its migration processes: a look at the present status

    Energy Technology Data Exchange (ETDEWEB)

    Mamun, C.K.; Ohkuma, H.; Sepehrnoori, K.

    1985-12-01

    In this study we review the present status of knowledge of solubility of hydrocarbons and its implications on primary migration processes. The intent is to examine the solubility and the transportation mechanisms relevant to geopressured-geothermal reservoirs, although the discussion included here accommodates a wide range of related aspects. Influences of parameters associated with hydrocarbon (especially methane) solubility have been studied. We have sought to evaluate several primary hydrocarbon migration processes and to point out their attractive features as well as their limitations. A brief discussion of hydrocarbon generation processes is also included.

  9. Steering proton migration in hydrocarbons using intense few-cycle laser fields

    OpenAIRE

    Kübel, M.; Siemering, R.; Burger, C.; Kling, Nora G.; Li, H; Alnaser, A. S.; Bergues, B.; Zherebtsov, S.; Azzeer, A. M.; Ben-Itzhak, I.; Moshammer, R.; de Vivie-Riedle, R.; Kling, M F

    2015-01-01

    Proton migration is a ubiquitous process in chemical reactions related to biology, combustion, and catalysis. Thus, the ability to control the movement of nuclei with tailored light, within a hydrocarbon molecule holds promise for far-reaching applications. Here, we demonstrate the steering of hydrogen migration in simple hydrocarbons, namely acetylene and allene, using waveform-controlled, few-cycle laser pulses. The rearrangement dynamics are monitored using coincident 3D ...

  10. Source and migration of light hydrocarbons indicated by carbon isotopic ratios

    International Nuclear Information System (INIS)

    Carbon isotopic ratios can distinguish among different sources of methane and can be used to correlate maturity of sediments with the methane. This technique has been applied to several wells and the isotopic values have been used to suggest the sources of the methane and whether the methane migrated into the area. Comparison of the isotopic ratio changes in ethane, propane, and butanes indicated that isotopic fractionation of methane by migration is not a major factor. The significant changes in methane isotopic ratio and the small changes in the isotopic ratios of these heavier hydrocarbons suggest that, although diffusion is not the sole process in migration, the time for migration is moderate

  11. Hydrocarbon migration and leakage dynamics of the Orange Basin, South Africa

    OpenAIRE

    Hartwig, Alexander

    2014-01-01

    The aim of this study is to delineate the active hydrocarbon (HC) kitchen and to characterize the hydrocarbon migration dynamics in the Orange Basin through time, and to investigate its potential impact on global climate on a geologic time scale by integrating seismic interpretation, organic geochemical analysis, and 3D petroleum system modeling techniques. The Orange Basin is located on the western passive margin offshore South Africa and contains more than 8 km of synrift and drift sediment...

  12. Steering proton migration in hydrocarbons using intense few-cycle laser fields

    CERN Document Server

    Kübel, M; Burger, C; Kling, Nora G; Li, H; Alnaser, A S; Bergues, B; Zherebtsov, S; Azzeer, A M; Ben-Itzhak, I; Moshammer, R; de Vivie-Riedle, R; Kling, M F

    2015-01-01

    Proton migration is a ubiquitous process in chemical reactions related to biology, combustion, and catalysis. Thus, the ability to control the movement of nuclei with tailored light, within a hydrocarbon molecule holds promise for far-reaching applications. Here, we demonstrate the steering of hydrogen migration in simple hydrocarbons, namely acetylene and allene, using waveform-controlled, few-cycle laser pulses. The rearrangement dynamics are monitored using coincident 3D momentum imaging spectroscopy, and described with a quantum-dynamical model. Our observations reveal that the underlying control mechanism is due to the manipulation of the phases in a vibrational wavepacket by the intense off-resonant laser field.

  13. Public Health Impacts of Secondary Particulate Formation from Aromatic Hydrocarbons in Gasoline

    Science.gov (United States)

    Background: Aromatic hydrocarbons emitted from gasoline?powered vehicles contribute to the formation of secondary organic aerosol (SOA), which increases the atmospheric mass concentration of fine particles (PM2.5). Here we estimate the public health burden associated w...

  14. Importance des phénomènes de migration verticale des hydrocarbures Significance of Vertical Migration Phenomea of Hydrocarbons

    Directory of Open Access Journals (Sweden)

    Chiarelle A.

    2006-11-01

    Full Text Available Cette publication a pour but de démonter les mécanismes de migration verticale des hydrocarbures et d'en analyser les conséquences, à partir d'exemples concrets choisis sur les domaines d'activité de la Société Nationale Elf Aquitaine (Production [SNEA (PJ. Les hydrocarbures, huile et gaz, rassemblés en phase individualisée évoluent dans un milieu poreux, fin, généralement mouillé à l'eau. Dans un tel environnement la migration suppose des pressions capillaires élevées. On démontre que cette condition se realise plus particulièrement sur Ies zones hautes fermées où les élements d'hydrocarbures expulses de la roche mère peuvent se rassembler en amas de taille importante, développant une forte poussee d'Archimède. De même le gaz, du fait de sa masse volumique faible par rapport à celle de l'eau, manifestera une grande aptitude à la migration verticale, ce qui conduira souvent à une redistribution verticale des hydrocarbures non conforme au schéma diagénétique classique : présence d'un gisement de gaz en surface et huile en profondeur. Combinés à l'effet Gussow, phénomène de refoulement de l'huile par le gaz hors de la fermeture critique d'une structure, les processus envisagés ici, où tes accidents tectoniques tiennent une place importante, aboutiront généralement à sil: aerer spatialement l'huile et le gaz. Ces transferts semblent s'accompagner fréquemment de modifications dans la composition chimique des huiles : augmentation des teneurs en soufre, en métaux traces, en hydrocarbures aromatiques, et alourdissement des huiles The purpose of this article is ta described the vertical migration mechanisms of hydrocarbons and to analyze their conséquences, on the basis of concrete examples selected in the fields of activities carried on by Société Nationale Elf Aquitaine (SNEA. When hydrocarbons (ai( and gas are gathered in a distinct phase, they evolve in a fine porous medium that is usually water wet. In such on environment, migration requires high capillary pressures. lt is shown that such conditions occur especially in high closed zones where the hydrocarbons driven out of the source rock con gather together in a large-sized mass, thus building up a high degree of buoyancy. In the same way, because gas has a louver specific gravity thon water, it has a great tendency ta migrote vertically, which often brings about a vertical redistribution of hydrocarbons that does not conform ta the conventional diagenetic pattern, i. e. the presence of a gas pool above a deeper ail pool.

  15. Numerical modeling of compositional variation in petroleum secondary migration; Modelagem numerica da variacao composicional na migracao secundaria de petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Magalhaes, Marcia Santos de Almeida

    1999-07-01

    The secondary migration of petroleum is analyzed in this study from a compositional perspective, with phase separation, using a numerical simulator. The modeling is focused on two different geologic scenarios, where migration occurs along the formation rocks or through a fault. Each scenario is initialized with a single-phase hydrocarbon bank, with mixtures defined in the oil and gas zones and in the proximity of the critical point in their respective phase envelopes. These fluids are obtained using a PVT simulator based on four samples (Black-oil, volatile oil and two retrograde gases) which generate various hydrocarbon mixtures from which some are selected to meet the pressure and temperature conditions established for the models. The results obtained indicate that the phase separation process, the migration and the oil and gas differences are adequately represented, and that this type of modeling may be used to explain complex fluid distribution in a single accumulation or petroleum province. However, the analysis of post-filling processes indicate the need for the inclusion of a diffusive term in the flow equations used in the simulator and for a higher precision in the fluid properties outputs. (author)

  16. Fracturing controlled primary migration of hydrocarbon fluids during heating of organic-rich shales

    CERN Document Server

    Kobchenko, Maya; Renard, Francois; Dysthe, Dag Kristian; Malthe-Sorenssen, Anders; Mazzini, Adriano; Scheibert, Julien; Jamtveit, Bjorn; Meakin, Paul

    2011-01-01

    Time-resolved three-dimensional in situ high resolution synchrotron x-ray tomographic imaging was used to investigate the effects of slowly heating organic-rich Green River Shale from 60\\deg; to 400\\deg;C, in air without confinement, to better understand primary migration of hydrocarbon fluids in very low permeability source rock. Cracks nucleate in the interior of the sample at a temperature around 350\\deg;C. As the temperature increases, they grow and coalesce along lamination planes to form bigger cracks. This process is accompanied by a release of light hydrocarbons generated by decomposition of the initially immature organic matter, as determined by thermogravimetry and gas chromatography. These results provide the first 4D monitoring of an invasion percolation-like fracturing process in organic-rich shales. This process increases the permeability of the sample and provides pathways for fluid expulsion - an effect that might also be relevant for primary migration under natural conditions. We propose a 2D...

  17. Secondary migration and relocation among African refugee families in the United States.

    Science.gov (United States)

    Weine, Stevan Merrill; Hoffman, Yael; Ware, Norma; Tugenberg, Toni; Hakizimana, Leonce; Dahnweigh, Gonwo; Currie, Madeleine; Wagner, Maureen

    2011-03-01

    The purpose of this study was to understand the secondary migration and relocation of African refugees resettled in the United States. Secondary migration refers to moves out of state, while relocation refers to moves within state. Of 73 recently resettled refugee families from Burundi and Liberia followed for 1 year through ethnographic interviews and observations, 13 instances of secondary migration and 9 instances of relocation were identified. A family ecodevelopmental framework was applied to address: Who moved again, why, and with what consequences? How did moving again impact family risk and protective factors? How might policies, researchers, and practitioners better manage refugees moving again? Findings indicated that families undertook secondary migration principally for employment, affordable housing, family reunification, and to feel more at home. Families relocated primarily for affordable housing. Parents reported that secondary migration and relocation enhanced family stability. Youth reported disruption to both schooling and attachments with peers and community. In conclusion, secondary migration and relocation were family efforts to enhance family and community protective resources and to mitigate shortcomings in resettlement conditions. Policymakers could provide newly resettled refugees jobs, better housing and family reunification. Practitioners could devise ways to better engage and support those families who consider moving. PMID:21361922

  18. Migration kinetics of mineral oil hydrocarbons from recycled paperboard to dry food: monitoring of two real cases.

    Science.gov (United States)

    Lorenzini, R; Biedermann, M; Grob, K; Garbini, D; Barbanera, M; Braschi, I

    2013-01-01

    Mineral oil hydrocarbons present in printing inks and recycled paper migrate from paper-based food packaging to foods primarily through the gas phase. Migration from two commercial products packed in recycled paperboard, i.e. muesli and egg pasta, was monitored up to the end of their shelf life (1 year) to study the influence of time, storage conditions, food packaging structure and temperature. Mineral oil saturated and aromatic hydrocarbons (MOSH and MOAH, respectively), and diisopropyl naphthalenes (DIPN) were monitored using online HPLC-GC/FID. Storage conditions were: free standing, shelved, and packed in transport boxes of corrugated board, to represent domestic, supermarket and warehouse storage, respectively. Migration to food whose packs were kept in transport boxes was the highest, especially after prolonged storage, followed by shelved and free-standing packs. Tested temperatures were representative of refrigeration, room temperature, storage in summer months and accelerated migration testing. Migration was strongly influenced by temperature: for egg pasta directly packed in paperboard, around 30 mg kg?¹ of MOSH migrated in 8 months at 20°C, but in only 1 week at 40°C. Muesli was contained into an internal polyethylene bag, which firstly adsorbed hydrocarbons and later released them partly towards the food. Differently, the external polypropylene bag, containing pasta and recycled paper tray, strongly limited the migration towards the atmosphere and gave rise to the highest level of food contamination. Tests at increased temperatures not only accelerated migration, but also widened the migration of hydrocarbons to higher molecular masses, highlighting thus a difficult interpretation of data from accelerated simulation. PMID:23406500

  19. Analysis of saturated and aromatic hydrocarbons migrating from a polyolefin-based hot-melt adhesive into food.

    Science.gov (United States)

    Lommatzsch, Martin; Biedermann, Maurus; Grob, Koni; Simat, Thomas J

    2016-03-01

    Hot-melt adhesives are widely utilised to glue cardboard boxes used as food packaging material. They have to comply with the requirements of Article 3 of the European Framework Regulation for food contact materials (1935/2004). The hot melt raw materials analysed mainly consisted of paraffinic waxes, hydrocarbon resins and polyolefins. The hydrocarbon resins, functioning as tackifiers, were the predominant source of hydrocarbons of sufficient volatility to migrate into dry foods: the 18 hydrocarbon resins analysed contained 8.2-118 g kg(-1) saturated and up to 59 g kg(-1) aromatic hydrocarbons eluted from GC between n-C16 and n-C24, substantially more than the paraffinic waxes and the polyolefins. These tackfier resins, especially the oligomers ≤ C24, have been characterised structurally by GC×GC-MS and (1)H-NMR spectroscopy. Migration into food was estimated using a simulating system with polenta as food simulant, which was verified by the analysis of a commercial risotto rice sample packed in a virgin fibre folding box sealed with a hot melt. About 0.5-1.5% of the potentially migrating substances (between n-C16 and n-C24) of a hot melt were found to be transferred into food under storage conditions, which can result in a food contamination in the order of 1 mg kg(-1) food (depending on the amount of potentially migrating substances from the hot melt, the hot melt surface, amount of food, contact time etc.). Migrates from hot melts are easily mistaken for mineral oil hydrocarbons from recycled cardboard. PMID:26744923

  20. Mobile and immobile migrated hydrocarbons in the Embla Field, North Sea

    Energy Technology Data Exchange (ETDEWEB)

    Bharati, Sunil

    1997-12-31

    This thesis deals with the geology of the Embla Field on the Norwegian Continental Shelf. This field has proven to be an excellent example to apply some of the recent ideas in reservoir geochemistry and has provided a sample set. Although the Embla field is in one of the most prolific regions of the Norwegian Continental Shelf, the Central Graben, its petroleum population is significantly different from neighbouring fields in more than one way. It is hoped that this work will provide a useful database for the planning of Embla`s further development. Migrated hydrocarbons are evaluated with respect to composition, maturity, intra-reservoir communication, compartmentalization and filling history of the field. The presence of immobile solid reservoir bitumen phase (paleo-oil) is mapped and explained and its origin and implications on overall reservoir quality are discussed. 206 refs., 118 figs., 34 tabs.

  1. Use of Invasion Percolation Models To Study the Secondary Migration of Oil and Related Problems

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, G.

    1997-12-31

    This thesis studies simulations of the slow displacement of a wetting fluid by a non-wetting fluid in porous media and in a single fracture. The simulations are based on the invasion percolation model. New modified versions of the model are presented that simulate migration, fragmentation and coalescence processes of the clusters of non-wetting fluid. The resulting displacement patterns are characterized by scaling laws. In particular, simulations of the secondary migration of oil through porous homogeneous rock are discussed. Fractured rocks are extreme cases of inhomogeneous porous media. Simulations of the slow displacement of a wetting fluid by a non-wetting fluid in a single fracture using the standard invasion model are presented. There is a discussion of a scenario in which a cluster of non-wetting fluid migrates through a porous medium that was saturated with a wetting fluid. The migration is driven by continuously driven buoyancy forces. Both experiments and simulations are described. The same scenario is also studied theoretically and by simulations using a simplified percolation model of fluid migration in one dimension. The migration model in two dimensions, with constant buoyancy forces, is also discussed. Simulations of fluid migration, such as the secondary migration of oil, in two- and three-dimensional media are examined, the media having multi-affine properties rather than being homogeneous. Slow immiscible displacement processes in single fractures are studied using fractal geometries to model single fractures. 167 refs., 123 figs.

  2. Analysis of carbon stable isotope to determine the origin and migration of gaseous hydrocarbon in the Brazilian sedimentary basins

    International Nuclear Information System (INIS)

    The carbon isotopic composition of natural gases to determine the origin and gaseous hydrocarbon migration of Brazilian sedimentar basins is analysed. The carbon isotopic ratio of methane from natural gases depends on the process of gas formation and stage of organic matter maturation. In the geochemical surface exploration the biogenic gases are differentiated from thermogenic gases, because the last one is isotopically heavier. As the isotopic composition of methane has not changed during migration, the migrated gases from deeper and more mature source rocks are identified by its relative 13C enrichment. The methane was separated from chromatography and and the isotopic analysis was done with mass spectrometer. (M.C.K.)

  3. Post-Secondary Education and Rural-Urban Migration

    Science.gov (United States)

    Synge, J.

    1974-01-01

    This study examined education and career plans of Scottish rural youth who entered post-secondary education in order to determine the extent to which the educational system offers rural youth not only specific training but only entry to the urban labour market. (Author/RK)

  4. Synthesis of secondary-alkyl-benzo[b]thiophene and their 2.3-dihydro derivatives with long hydrocarbon radicals

    International Nuclear Information System (INIS)

    Present article is devoted to synthesis of secondary-alkyl-benzo[b]thiophene and their 2.3-dihydro derivatives with long hydrocarbon radicals. The results of studies of methods of obtaining of alkyl-benzo[b]thiophene and their 2.3-dihydro derivatives with long hydrocarbon radicals were considered.

  5. Obstructive jaundice secondary to endoclip migration into common bile duct after laparoscopic cholecystectomy.

    Science.gov (United States)

    Sormaz, I C; Keskin, M; Sönmez, R E; Soyta?, Y; Tekant, Y; Avtan, L

    2015-10-01

    Obstructive jaundice is a rare condition due to foreign body in common bile. In this article we report a 69 year-old man who was diagnosed obstructive jaundice secondary to the endoscopic clip migration. The patient had been performed laparoscopic cholecystectomy 5 years ago and had recovered without any complications. He presented with abdominal pain and jaundice. The magnetic resonance cholangiopancreatography (MRCP) revealed filling defect in choledoch consistent with a bile duct stone. The endoscopic retrograde cholangiopancreatography (ERCP) exhibited an endoclip migration into the common bile duct which caused bile duct stone. Endoclips can migrate into bile duct and cause obstructive jaundice. ERCP is the first option for its treatment. PMID:26488761

  6. / Vanadium, nickel and porphyrins as tracers of secondary migration route of petroleum: Maracaibo Lake Basin, Venezuela

    Scientific Electronic Library Online (English)

    Marcos, Escobar; Angel, Da Silva; Vicmar, Azuaje; Iván, Esteves.

    2007-11-01

    Full Text Available Vanadio, níquel y porfirinas como trazadores de rutas de migración secundaria del petróleo: Cuenca del lago de Maracaibo, Venezuela [...] Abstract in english A model of secondary migration for the Marcelina (Paleocene) reservoir of the Alturitas oil field located in the Maracaibo Basin is proposed. For this purpose, diverse trace metals and biomarker-derived parameters were used, for a suite of 30 crude oil samples analyzed by SARA, GC-MS, ICP-OES and UV [...] -Visible techniques. Considering a unique geochemical type of crude oil in the reservoir [1-2], distributional changes along the reservoir area for selected parameters was studied. Ten trace metals were analyzed and splitted into two groups using multivariate statistic. The first group (Cd, Cu, Mo, Fe, P, Zn, Ca, Mg) does not display behaviors that can be associated to the secondary migration process but which rather they indicate a chalcophic association (Cd, Cu, Mo y Zn) or colloidal complexes with naphtenic acids (Ca, Mg, Fe). The behavior of the second groups, including total crude oil vanadium, nickel, porphyrins and resins plus asphaltenes concentrations, indicates that a natural chromatographic process has been affecting the crude oil composition, leading the proposition of a secondary migration route with a south-north oriented preferential migration axis. The analysis of different biomarkers did not throw clear results as far as the characterization of the process of migration and accumulation in the reservoir.

  7. A 4D synchrotron X-ray tomography study of the formation of hydrocarbon migration pathways in heated organic-rich shale

    CERN Document Server

    Panahi, Hamed; Renard, Francois; Mazzini, Adriano; Scheibert, Julien; Dysthe, Dag Kristian; Jamtveit, Bjorn; Malthe-Sørenssen, Anders; Meakin, Paul

    2014-01-01

    Recovery of oil from oil shales and the natural primary migration of hydrocarbons are closely related processes that have received renewed interests in recent years because of the ever tightening supply of conventional hydrocarbons and the growing production of hydrocarbons from low permeability tight rocks. Quantitative models for conversion of kerogen into oil and gas and the timing of hydrocarbon generation have been well documented. However, lack of consensus about the kinetics of hydrocarbon formation in source rocks, expulsion timing and how the resulting hydrocarbons escape from or are retained in the source rocks motivates further investigation. In particular, many mechanisms for the transport of hydrocarbons from the source rocks in which they are generated into adjacent rocks with higher permeabilities and smaller capillary entry pressures have been proposed, and a better understanding of this complex process (primary migration) is needed. To characterize these processes it is imperative to use the ...

  8. Elimination of polycyclic aromatic hydrocarbons from smoked sausages by migration into polyethylene packaging.

    Science.gov (United States)

    Semanová, Jana; Skláršová, Božena; Šimon, Peter; Šimko, Peter

    2016-06-15

    The objective of this work was a study of interactions between a smoked meat product and plastic packaging to find a possibility of elimination of polycyclic aromatic hydrocarbons (PAH) from smoked sausages by migration into the packaging. Smoked meat sausages were packed into o-polyamide/low density polyethylene laminated film and content of four PAH was determined at 0, 15, 30, 45, 60, 75, 90, 120, 150 and 180min by HPLC. During this time, total PAH4 content decreased from 30.1 to 5.7μg/kg, benzo[a]anthracene decreased from 11.5 to 2.1μg/kg, chrysene from 9.4 to 1.9μg/kg, benzo[b]fluoranthene from 5.3 to 0.6μg/kg and benzo[a]pyrene from 3.9 to 1.1μg/kg while PAH4 content in non-packed sausages remained at a constant level. So, while sausages did not meet European safety limits set for PAH4 content of 12μg/kg and 2μg/kg for benzo[a]pyrene before packaging, these limits were met at the end of the experiment. This decrease was brought about by migration of PAH4 from sausages into low density polyethylene packaging bulk and the measure of decrease can be predicted by a kinetic equation, making it possible to calculate PAH content equal to any time of experiment as well as the time of interaction necessary to fulfil EU legislative limits. PMID:26868540

  9. Use of Invasion Percolation Models To Study the Secondary Migration of Oil and Related Problems

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, G.

    1997-09-01

    In oil reservoir engineering, multi-phase displacement processes are important. This doctoral thesis describes simulations of the slow displacement of a wetting fluid by a non-wetting fluid in a complex, random porous medium and in a single fracture. The study is restricted to two-phase flow in the quasi-static limit in which viscous forces can be neglected. The secondary migration of oil takes place in this regime, however, the discussion is broader in scope. The thesis connects the problem of slow two-phase flow to percolation theory and discusses the mechanisms that control immiscible displacements. A new, modified version of the invasion percolation model is used to simulate an imbibition process in a porous medium and the migration of a cluster of non-wetting fluid through a porous medium saturated with a wetting fluid. The simulations include the secondary migration of oil through porous homogeneous rock. Fluid migration through heterogeneous porous media is simulated qualitatively. Slow displacement of a wetting fluid by a non-wetting fluid in a single rock fracture is simulated by using the standard invasion percolation model. Experiments and simulations are performed to study the fragmentation of invasion percolation-like structures of non-wetting fluid in a porous medium saturated with a wetting fluid. A scenario is studied in which a cluster of non-wettable fluid migrates through a porous medium that is saturated with a wetting fluid, the migration being driven by continuously increasing buoyancy forces. There is a simulation of the secondary migration of oil in both two- and three-dimensional media. 361 refs., 115 figs.

  10. Large-Scale Multiphase Flow Modeling of Hydrocarbon Migration and Fluid Sequestration in Faulted Cenozoic Sedimentary Basins, Southern California

    Science.gov (United States)

    Jung, B.; Garven, G.; Boles, J. R.

    2011-12-01

    Major fault systems play a first-order role in controlling fluid migration in the Earth's crust, and also in the genesis/preservation of hydrocarbon reservoirs in young sedimentary basins undergoing deformation, and therefore understanding the geohydrology of faults is essential for the successful exploration of energy resources. For actively deforming systems like the Santa Barbara Basin and Los Angeles Basin, we have found it useful to develop computational geohydrologic models to study the various coupled and nonlinear processes affecting multiphase fluid migration, including relative permeability, anisotropy, heterogeneity, capillarity, pore pressure, and phase saturation that affect hydrocarbon mobility within fault systems and to search the possible hydrogeologic conditions that enable the natural sequestration of prolific hydrocarbon reservoirs in these young basins. Subsurface geology, reservoir data (fluid pressure-temperature-chemistry), structural reconstructions, and seismic profiles provide important constraints for model geometry and parameter testing, and provide critical insight on how large-scale faults and aquifer networks influence the distribution and the hydrodynamics of liquid and gas-phase hydrocarbon migration. For example, pore pressure changes at a methane seepage site on the seafloor have been carefully analyzed to estimate large-scale fault permeability, which helps to constrain basin-scale natural gas migration models for the Santa Barbara Basin. We have developed our own 2-D multiphase finite element/finite IMPES numerical model, and successfully modeled hydrocarbon gas/liquid movement for intensely faulted and heterogeneous basin profiles of the Los Angeles Basin. Our simulations suggest that hydrocarbon reservoirs that are today aligned with the Newport-Inglewood Fault Zone were formed by massive hydrocarbon flows from deeply buried source beds in the central synclinal region during post-Miocene time. Fault permeability, capillarity forces between the fault and juxtaposition of aquifers/aquitards, source oil saturation, and rate of generation control the efficiency of a petroleum trap and carbon sequestration. This research is focused on natural processes in real geologic systems, but our results will also contribute to an understanding of the subsurface behavior of injected anthropogenic greenhouse gases, especially when targeted storage sites may be influenced by regional faults, which are ubiquitous in the Earth's crust.

  11. Secondary Aerosol Formation from Oxidation of Aromatics Hydrocarbons by Cl atoms

    Science.gov (United States)

    Cai, X.; Griffin, R.

    2006-12-01

    Aerosol Formation From the Oxidation of Aromatic Hydrocarbons by Chlorine Atmospheric secondary organic aerosol (SOA) affects regional and global air quality. The formation mechanisms of SOA via the oxidation of volatile organic compounds by hydroxyl radicals, ozone, and nitrate radicals have been studied intensively during the last decade. Chlorine atoms (Cl) also have been hypothesized to be effective oxidants in marine and industrially influenced areas. Recent work by the authors has indicated that significant amounts of SOA are formed from the oxidation of monoterpenes by Cl. Aromatic hydrocarbons are important for generation of both SOA and ozone in urban areas because of their large emission rates and high reactivity. The goal of this work was to quantify the SOA formation potentials of two representative aromatic hydrocarbons through laboratory chamber experiments in which oxidation was initiated by Cl. The system constructed for this study includes an experimental chamber, a gas chromatograph for quantification of aromatic mixing ratios, a Scanning Mobility Particle Spectrometer to measure SOA size distributions, a zero air generator, and an illuminating system. The model aromatic hydrocarbons chosen for this study are toluene and m-xylene. Aerosol yields are estimated based on measured aerosol volume concentration, the concentration of consumed hydrocarbon, and estimation of wall loss of the newly formed aerosol. Toluene and m-xylene exhibit similar SOA yields from the oxidation initiated by Cl. The toluene SOA yield from Cl-initiated oxidation, however, depends on the ratio between the mixing ratios of the initial chlorine source and toluene in the chamber. For toluene experiments with higher such ratios, SOA yields vary from 0.05 to 0.079 for generated aerosol ranging from 4.2 to12.0 micrograms per cubic meter. In the lower ratio experiments, SOA yields are from 0.033 to 0.064, corresponding to generated aerosol from 3.0 to 11.0 micrograms per cubic meter. The m-xylene SOA yield ranges from 0.04 to 0.08 for aerosol in the range of 4.0 to 12.0 micrograms per cubic meter. These yields are generally comparable to those from photooxidation. In marine and industrial areas, SOA formation from the Cl- initiated oxidation of the studied common aromatics is likely to be most important in the early morning.

  12. SATURATED AND AROMATIC MINERAL OIL HYDROCARBONS FROM PAPERBOARD FOOD PACKAGING: ESTIMATION OF LONG-TERM MIGRATION FROM CONTENTS IN THE PAPERBOARD & DATA ON BOXES FROM THE MARKET

    OpenAIRE

    Lorenzini, Rita; Fiselier, Katel; Biedermann, Maurus; Barbanera, Martino; Braschi, Ilaria; Grob, Konrad

    2010-01-01

    Abstract In the absence of a functional barrier, mineral oil hydrocarbons from printing inks and recycled fibers tend to migrate from paper-based food packaging materials through the gas phase into dry food. Concentrations easily far exceed the limit derived from the Acceptable Daily Intake (ADI) of the Joint FAO/WHO Expert Committee on Food Additives (JECFA). Since estimation of long-term migration into the food by testing at 40°C for 10 days is difficult, it seems preferable (and...

  13. Geochemical assessment of hydrocarbon migration phenomena: Case studies from the south-western margin of the Dead Sea Basin

    Science.gov (United States)

    Sokol, Ella; Kozmenko, Olga; Smirnov, Sergey; Sokol, Ivan; Novikova, Sofya; Tomilenko, Anatoliy; Kokh, Svetlana; Ryazanova, Tatyana; Reutsky, Vadim; Bul'bak, Taras; Vapnik, Yevgeny; Deyak, Michail

    2014-10-01

    Calcite veins with fluid and solid bitumen inclusions have been discovered in the south-western shoulder of the Dead Sea rift within the Masada-Zohar block, where hydrocarbons exist in small commercial gas fields and non-commercial fields of heavy and light oils. The gas-liquid inclusions in calcite are dominated either by methane or CO2, and aqueous inclusions sometimes bear minor dissolved hydrocarbons. The enclosed flake-like solid bitumen matter is a residue of degraded oil, which may be interpreted as “dead carbon”. About 2/3 of this matter is soot-like amorphous carbon and 1/3 consists of n-C8sbnd C18 carboxylic acids and traces of n-alkanes, light dicarboxylic acids, and higher molecular weight (>C20) branched and/or cyclic carboxylic acids. Both bitumen and the host calcites show genetic relationship with mature Maastrichtian chalky source rocks (MCSRs) evident in isotopic compositions (?13C, ?34S, and ?18O) and in REE + Y patterns. The bitumen precursor may have been heavy sulfur-rich oil which was generated during the burial compaction of the MCSR strata within the subsided blocks of the Dead Sea graben. The ?18O and ?13C values and REE + Y signatures in calcites indicate mixing of deep buried fluids equilibrated with post-mature sediments and meteoric waters. The temperatures of fluid generation according to Mg-Li-geothermometer data range from 55 °? to 90 °? corresponding to the 2.5-4.0 km depths, and largely overlap with the oil window range (60-90 °?) in the Dead Sea rift (Hunt, 1996; Gvirtzman and Stanislavsky, 2000; Buryakovsky et al., 2005). The bitumen-rich vein calcites originated in the course of Late Cenozoic rifting and related deformation, when tectonic stress triggers damaged small hydrocarbon reservoirs in the area, produced pathways, and caused hydrocarbon-bearing fluids to rise to the subsurface; the fluids filled open fractures and crystallized to calcite with entrapped bitumen. The reported results are in good agreement with the existing views of maturation, migration, and accumulation of hydrocarbons, as well as basin fluid transport processes in the Dead Sea area.

  14. Information content of geochemical indicators of the migration direction of hydrocarbons and its quantitative evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Kushnirov, V.V.

    1981-01-01

    The effect of factors which accompany the process of retrograde evaportion of petroleum and compressed gases on the value of different geochemical indicators which are used as criteria of the direction of carbonaceous material migration is indicated. A method of quantitative evaluation of lateral and vertical movement of liquid and gas-like carbonaceous material in gas-condensate deposits is proposed.

  15. Migration of mineral hydrocarbons into foods. 6. Press lubricants used in food and beverage cans.

    Science.gov (United States)

    Jickells, S M; Nichol, J; Castle, L

    1994-01-01

    Unused food and beverage cans were supplied by manufacturers together with two typical samples of press lubricants used to facilitate stamping of can ends. The lubricants were based on mineral hydrocarbon fractions. The cans were of aluminium two-piece construction (two sizes) and tin-plate steel three-piece construction (two sizes) and of four representative types. Gas chromatographic analysis was used to distinguish the two press lubricants from one another by their n-alkane profiles. Analysis of solvent extracts of the cans indicated that one of the two press lubricants had been used in the manufacture of the three-piece cans and the other lubricant for the two-piece cans. Residual levels of hydrocarbons were between 0.05 and 1.1 mg per can. Based on the capacity of the cans and assuming all the mineral hydrocarbon transferred to the contents, maximum levels in foods and beverages could be between 0.1 and 4.4 mg/kg. A limited number of retail products were also analysed. For the 35 samples covering 18 retail brands of canned foods and beverages, press lubricants were considered to be present in 50% of the products at levels ranging from 0.05 to 1.0 mg per can, equivalent to 0.1 to 3.6 mg/kg of food. Additionally mineral oil of unknown origin was detected in 10 of the retail products at levels of 0.1 to 4.7 mg/kg. Analysis of a sparkling apple juice packed in a glass bottle showed mineral oil at 0.3 mg/kg compared with 0.7 mg/kg for the same canned product, indicating that although mineral oils may be used in can manufacture they may also be derived from other parts of the food processing chain. PMID:7835472

  16. Unraveling the Timing of Fluid Migration and Trap Formation in the Brooks Range Foothills: A Key to Discovering Hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Catherine L. Hanks

    2008-12-31

    Naturally occurring fractures can play a key role in the evolution and producibility of a hydrocarbon accumulation. Understanding the evolution of fractures in the Brooks Range/Colville basin system of northern Alaska is critical to developing a better working model of the hydrocarbon potential of the region. This study addressed this problem by collecting detailed and regional data on fracture distribution and character, structural geometry, temperature, the timing of deformation along the Brooks Range rangefront and adjacent parts of the Colville basin, and the in situ stress distribution within the Colville basin. This new and existing data then were used to develop a model of how fractures evolved in northern Alaska, both spatially and temporally. The results of the study indicate that fractures formed episodically throughout the evolution of northern Alaska, due to a variety of mechanisms. Four distinct fracture sets were observed. The earliest fractures formed in deep parts of the Colville basin and in the underlying Ellesmerian sequence rocks as these rocks experienced compression associated with the growing Brooks Range fold-and-thrust belt. The orientation of these deep basin fractures was controlled by the maximum in situ horizontal stress in the basin at the time of their formation, which was perpendicular to the active Brooks Range thrust front. This orientation stayed consistently NS-striking for most of the early history of the Brooks Range and Colville basin, but changed to NW-striking with the development of the northeastern Brooks Range during the early Tertiary. Subsequent incorporation of these rocks into the fold-and-thrust belt resulted in overprinting of these deep basin fractures by fractures caused by thrusting and related folding. The youngest fractures developed as rocks were uplifted and exposed. While this general order of fracturing remains consistent across the Brooks Range and adjacent Colville basin, the absolute age at any one location varies. Fracturing started in the southwest deep in the stratigraphic section during the Late Jurassic and Early Cretaceous, moving northeastward and upsection as the Colville basin filled from the west. Active fracturing is occurring today in the northeastern parts of the Colville basin, north of the northeastern Brooks thrust front. Across northern Alaska, the early deep basin fractures were probably synchronous with hydrocarbon generation. Initially, these early fractures would have been good migration pathways, but would have been destroyed where subsequently overridden by the advancing Brooks Range fold-and-thrust belt. However, at these locations younger fracture sets related to folding and thrusting could have enhanced reservoir permeability and/or served as vertical migration pathways to overlying structural traps.

  17. Formation of radical cations and hole migration upon irradiation of frozen solutions of aromatic hydrocarbons

    International Nuclear Information System (INIS)

    Radiation induced chemical processes occurring in the course of irradiation at 77 K of benzene, toluene, ethylbenzene solutions and their mixtures in freon-113 (CFCl2CF2Cl) in 60Co ?-facility up to a dose of 1 Mrad, are studied by the method of ESR spectroscopy. It is shown that hole transfer from cation radicals to neutral molecules of aromatic hydrocarbons in solid matrix is a conformation-controlled process occurring at a distance of 2-4 nm in all probability according to tunnel mechanism

  18. Petroleum Weathering Associated with Hydrocarbon Migration and Seepage, a Case Study From the Santa Barbara Channel, CA.

    Science.gov (United States)

    Wardlaw, G. D.; Nelson, R. K.; Reddy, C. M.; Valentine, D. L.

    2005-12-01

    A 2003 report by the National Research Council estimates that 50 to 70 percent of oil that is released into the sea is from natural seeps (National Research Council, 2003), indicating that catastrophic oil spills or the runoff from roads and highways are not the major sources of oil in the marine environment. For example, approximately 37 tons of petroleum is emitted daily from seeps off the coast of Santa Barbara, California (Quigley et al. 1996). The Santa Barbara seeps are some of the most active in the world and have been releasing petroleum for thousands of years. Sheens of oil on the water surface and tar patches on the beaches are ubiquitous along the coastline of Santa Barbara and are continuing reminders of this natural process. Although the geochemistry of these seeps have been studied in the past, it has been hindered by the complexity of the petroleum hydrocarbons and the inability of traditional gas chromatography to separate, identify, and quantify each component of the oil. To expand on these previous efforts, we have begun to use comprehensive two-dimensional gas chromatography (GCxGC). This new technology provides at least an order of magnitude increase in the resolution and detection of petroleum hydrocarbons compared to traditional methods. Preliminary work using GCxGC has focused on examining the chemical composition of unrefined petroleum as it migrates up from depth through natural faults to the seafloor, from the seafloor to the sea surface, and from the sea surface to local beaches. Petroleum collected from a subsurface reservoir (Platform Holly Well 2342-15) is composed of a wide range of resolved petroleum hydrocarbons including n-alkanes, branched alkanes, cycloalkanes, linear alkane benzenes, polycyclic aromatic hydrocarbons, steranes, hopanes, cyclic isoprenoids, and very large branched biomarkers with 38 to 40 carbons. This product is significantly different than oil emerging from the seafloor at the Jackpot seep, which we believe is due to biodegradation. Alternatively, direct comparisons of the latter to samples collected on the sea surface show extensive losses of light-end components due to evaporation and not water washing. Tar balls collected from nearby beaches appear to be the end result of biodegradation, evaporation, and water washing of the original material seeping from the ocean floor. These initial studies reveal that the geochemistry and processes acting on petroleum seeping from the ocean floor are complex. Efforts are underway to construct accurate models that will quantify each environmental process that affects the fate of petroleum in the marine environment.

  19. Migrating Tundra Peregrine Falcons accumulate polycyclic aromatic hydrocarbons along Gulf of Mexico following Deepwater Horizon oil spill.

    Science.gov (United States)

    Seegar, William S; Yates, Michael A; Doney, Gregg E; Jenny, J Peter; Seegar, Tom C M; Perkins, Christopher; Giovanni, Matthew

    2015-07-01

    Monitoring internal crude oil exposure can assist the understanding of associated risks and impacts, as well as the effectiveness of restoration efforts. Under the auspices of a long-term monitoring program of Tundra Peregrine Falcons (Falco peregrinus tundrius) at Assateague (Maryland) and South Padre Islands (Texas), we measured the 16 parent (unsubstituted) polycyclic aromatic hydrocarbons (PAHs), priority pollutants identified by the United States Environmental Protection Agency and components of crude oil, in peripheral blood cells of migrating Peregrine Falcons from 2009 to 2011. The study was designed to assess the spatial and temporal trends of crude oil exposure associated with the 2010 Deepwater Horizon (DWH) oil spill which started 20 April 2010 and was capped on 15 July of that year. Basal PAH blood distributions were determined from pre-DWH oil spill (2009) and unaffected reference area sampling. This sentinel species, a predator of shorebirds and seabirds during migration, was potentially exposed to residual oil from the spill in the northern Gulf of Mexico. Results demonstrate an increased incidence (frequency of PAH detection and blood concentrations) of PAH contamination in 2010 fall migrants sampled along the Texas Gulf Coast, declining to near basal levels in 2011. Kaplan-Meier peak mean ?PAH blood concentration estimates varied with age (Juveniles-16.28 ± 1.25, Adults-5.41 ± 1.10 ng/g, wet weight) and PAHs detected, likely attributed to the discussed Tundra Peregrine natural history traits. Increased incidence of fluorene, pyrene and anthracene, with the presence of alkylated PAHs in peregrine blood suggests an additional crude oil source after DWH oil spill. The analyses of PAHs in Peregrine Falcon blood provide a convenient repeatable method, in conjunction with ongoing banding efforts, to monitoring crude oil contamination in this avian predator. PMID:25794559

  20. The distribution of functionality types in hydroxyoligobutadienes obtained in hydrocarbon media under the action of di-secondary dilithium alkanes

    International Nuclear Information System (INIS)

    It was found that hydroxyoligobutadienes obtained in hydrocarbon solvents via reactions initiated by di-secondary dilithium alkanes contain, in addition to the target bifunctional fraction, the mono- and trifunctional fractions and a branched bifunctional function. It was established that a distribution of the functionality types is formed in the initial stage of the degree of the process. It is demonstrated that the degree of molecular homogeneity of the oligomers can be increased (with the bifunctional fraction reaching up 90 % and above) by conducting the process in two stages. An insoluble 'living' oligomer, enriched by the bifunctional fraction, is isolated in the first stage and used as a 'secondary initiator' in the second stage. 19 refs., 4 figs., 1 tab

  1. Aluminum/hydrocarbon gel propellants: An experimental and theoretical investigation of secondary atomization and predicted rocket engine performance

    Science.gov (United States)

    Mueller, Donn Christopher

    1997-12-01

    Experimental and theoretical investigations of aluminum/hydrocarbon gel propellant secondary atomization and its potential effects on rocket engine performance were conducted. In the experimental efforts, a dilute, polydisperse, gel droplet spray was injected into the postflame region of a burner and droplet size distributions was measured as a function of position above the burner using a laser-based sizing/velocimetry technique. The sizing/velocimetry technique was developed to measure droplets in the 10-125 mum size range and avoids size-biased detection through the use of a uniformly illuminated probe volume. The technique was used to determine particle size distributions and velocities at various axial locations above the burner for JP-10, and 50 and 60 wt% aluminum gels. Droplet shell formation models were applied to aluminum/hydrocarbon gels to examine particle size and mass loading effects on the minimum droplet diameter that will permit secondary atomization. This diameter was predicted to be 38.1 and 34.7 mum for the 50 and 60 wt% gels, which is somewhat greater than the experimentally measured 30 and 25 mum diameters. In the theoretical efforts, three models were developed and an existing rocket code was exercised to gain insights into secondary atomization. The first model was designed to predict gel droplet properties and shell stresses after rigid shell formation, while the second, a one-dimensional gel spray combustion model was created to quantify the secondary atomization process. Experimental and numerical comparisons verify that secondary atomization occurs in 10-125 mum diameter particles although an exact model could not be derived. The third model, a one-dimensional gel-fueled rocket combustion chamber, was developed to evaluate secondary atomization effects on various engine performance parameters. Results show that only modest secondary atomization may be required to reduce propellant burnout distance and radiation losses. A solid propellant engine code was employed to estimate nozzle two-phase flow losses and engine performance for upper-stage and booster missions (3-6% and 2-3%, respectively). Given these losses and other difficulties, metallized gel propellants may be impractical in high-expansion ratio engines. Although uncertainties remain, it appears that performance gains will be minimal in gross-weight limited missions, but that significant gains may arise in volume-limited missions.

  2. Migration of selected hydrocarbon contaminants into dry semolina and egg pasta packed in direct contact with virgin paperboard and polypropylene film.

    Science.gov (United States)

    Barp, Laura; Suman, Michele; Lambertini, Francesca; Moret, Sabrina

    2015-01-01

    Migration of mineral oil saturated hydrocarbons (MOSH), polyolefin oligomeric saturated hydrocarbons (POSH), and polyalphaolefins (PAO from hot melts) into dry semolina and egg pasta packed in direct contact with virgin paperboard or polypropylene (PP) flexible film was studied. Migration was monitored during shelf life (up to 24 months), through storage in a real supermarket (packs kept on shelves), conditions preventing exchange with the surrounding environment (packs wrapped in aluminium foil), and storage in a warehouse (packs inside of the transport box of corrugated board). Semolina pasta packed in virgin paperboard (without hot melts) had a MOSH content lower than 1.0 mg kg(-1). An increasing contamination with PAO belonging to the adhesives used to close the boxes was detected in egg pasta, wrapped in aluminium (1.5 and 5 mg kg(-1) after 3 and 24 months, respectively). An environmental contribution to total hydrocarbon contamination was observed in egg pasta kept on shelves that, after 3 and 24 months, showed levels of PAO/MOSH pasta wrapped in aluminium was around 0.6 mg kg(-1) after 3 months of contact and reached 1.7 mg kg(-1) after 24 months of contact. After 9 months of contact, semolina pasta packed in PP film and stored in the transport box showed that some MOSH migrated into the pasta from the board of the transport box (through the plastic film). PMID:26209063

  3. Stable carbon isotopic fractionation of individual n-alkanes accompanying primary migration: Evidence from hydrocarbon generation-expulsion simulations of selected terrestrial source rocks

    International Nuclear Information System (INIS)

    The effect of isotopic fractionation during primary migration of hydrocarbons from coals is rarely noticed because it overlaps with the isotopic effects of maturation. In this research, geological chromatography-like effects and possible physical isotopic fractionation effects on n-alkanes during primary migration from four coals and one mudstone were studied through two types of generation-expulsion simulations (generation-expulsion simulations I and II). In order to monitor the kinetic isotopic fractionation effect during primary migration and to differentiate the isotopic effects of primary migration from the isotopic effects of maturation, generation-expulsion simulation was upgraded in two aspects, source rock was separated into at least five layers, and deuterated n-C15D32 was added to the initial layer of the source rock (simulation II). The experimental results suggested that all terrestrial source rocks exhibit significant geological chromatography-like effects in generation-expulsion simulation. Expulsion efficiencies shown by vitrinite-rich coals are much lower than algal cannel, fusinite-rich coal and mudstone. There also exist significant physical isotopic fractionation effects in hydrocarbon primary migration processes from vitrinite-rich coals, but there is no significant isotopic fractionation effect from fusinite-rich brown coal and mudstone. Pore structure and specific surface area of source rock samples were measured by gas adsorption of both N2 and CO2. This indicated that vitrinite-rich coals have a higher proportion of microporosity. The differences in pore structure and adsorptive capacity of source rocks may be responsible for differences in expulsion efficiencies and isotopic fractionation effects in generation-expulsion simulations. The isotopic fractionation effect due to primary migration should be considered in making oil-source correlation when vitrinite-rich coals are concerned.

  4. Secondary Glaucoma Associated with Encircling Scleral Buckle Migration into the Cornea

    Directory of Open Access Journals (Sweden)

    Şengül Özdek

    2016-01-01

    Full Text Available Transmuscular migration of the encircling band through rectus muscles and straddling of the cornea has only been reported in a few cases previously in the literature. This rare condition has never been associated with glaucoma. In this report, we aimed to describe a unique case with transmuscular migration of encircling buckle as a probable cause of glaucoma. A 17-year-old female presented with transmuscular migration of buckle and high intraocular pressure (IOP. Limbal/corneal migration of the silicone band was thought to be the main reason for the IOP rise; therefore, scleral band removal was performed. One month after removal, the patient was free of glaucoma medications and IOP was within normal limits. The retina remained attached during all postoperative visits. Transmuscular migration of the encircling band through rectus muscles and straddling of the cornea may act as a trigger for glaucoma.

  5. Evidence of subsurface anaerobic biodegradation of hydrocarbons and potential secondary methanogenesis in terrestrial mud volcanoes

    OpenAIRE

    Etiope, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Feyzullayev, A.; Geology Institute of the Azerbaijan National Academy of Sciences, Baku, Azerbaijan; Milkov, A. V.; BP, Russia Offshore SPU, Moscow, Russia; Waseda, A.; Japan Petroleum Exploration Co., JAPEX Research Center, Chiba, Japan; Mizobe, K.; Japan Petroleum Exploration Co., JAPEX Research Center, Chiba, Japan; Sun, C. H.; Exploration and Development Research Institute, CPC Taiwan, Taiwan, ROC

    2009-01-01

    The assessment of gas origin in mud volcanoes and related petroleum systems must consider postgenetic processes which may alter the original molecular and isotopic composition of reservoir gas. Beyond eventual molecular and isotopic fractionation due to gas migration and microbial oxidation, investigated in previous studies, we now demonstrate that mud volcanoes can show signals of anaerobic biodegradation of natural gas and oil in the subsurface. A large set of gas geochemical data fro...

  6. Modern Processes of Hydrocarbon Migration and Re-Formation of Oil and Gas Fields (Based on the Results of Monitoring and Geochemical Studies)

    Science.gov (United States)

    Plotnikova, Irina; Salakhidinova, Gulmira; Nosova, Fidania; Pronin, Nikita; Ostroukhov, Sergey

    2015-04-01

    Special geochemical studies of oils allowed to allocate a movable migration component of oils in the industrial oil deposits. In the field the migration component of oils varies in different parts of the field. The largest percentage of the light migration component (gas condensate of the oil) was detected in the central part of the Kama-Kinel troughs system. Monitoring of the composition of water, oil and gas (condensate light oil component) in the sedimentary cover and ni crystalline basement led to the conclusion of modern migration of hydrocarbons in sedimentary cover. This proves the existence of the modern processes of formation and reformation of oil and gas fields. This presentation is dedicated to the problem of definition of geochemical criteria of selection of hydrocarbons deposit reformation zone in the sample wells of Minibaevskaya area of Romashkinskoye field. While carrying out this work we examined 11 samples of oil from the Upper Devonian Pashiysky horizon. Four oil samples were collected from wells reckoned among the "anomalous" zones that were marked out according to the results of geophysical, oil field and geological research. Geochemical studies of oils were conducted in the laboratory of geochemistry of the Kazan (Volga-region) Federal University. The wells where the signs of hydrocarbons influx from the deep zones of the crust were recorded are considered to be "anomalous". A number of scientists connect this fact to the hypothesis about periodic influx of deep hydrocarbons to the oil deposits of Romashkinskoye field. Other researchers believe that the source rocks of the adjacent valleys sedimentary cover generate gases when entering the main zone of gas formation, which then migrate up the section and passing through the previously formed deposits of oil, change and "lighten" their composition. Regardless of the point of view on the source of the hydrocarbons, the study of the process of deposits refilling with light hydrocarbons is an important fundamental task of exceptional practical importance. The reservoir water monitoring has been conducted in five wells that have penetrated the water-saturated, loosely aggregated zones of the South Tatarstan Arch's basement. The long-term testing resulted in the production of reservoir water from the basement. The sedimentary cover in these wells is blocked by the column, which prevents water cross-flowing from the sedimentary cover. The observations have shown that the levels, gas saturation, mineralisation, density, and composition of reservoir waters from the loosely aggregated zones of the basement change with time. The varying characteristics of the water include its component composition, redox potential, and amount of chlorine and some other components and trace elements. Compositional changes in gases of the loosely aggregated zones of the basement, variations in the gas saturation of reservoir waters and of their composition, the decreasing density of oil in the sedimentary cover, - all result from one cause. This cause is the movement of fluids (solutions and gases dissolved in them) through the loosely aggregated zones and faults of the Earth's crust and the sedimentary cover. The fluids mainly move vertically in an upward direction, although their migration through subhorizontal, loosely aggregated zones of the crystalline basement is also possible. Fluid migration still takes place in the Earth's crust of ancient platforms. This phenomenon indicates that some portions of the platforms - primarily, their margins - periodically resume tectonic activities. The fluid dynamic activity of the crust define the processes in the sedimentary cover. It affects the development of the sedimentary basin during the sedimentation period, and the formation of mineral deposits. The monitoring of the present-day movement of fluid systems in the loosely aggregated zones of the basement will permit the more detailed study of the present-day fluid regime in the upper portion of the Earth's crust and the sedimentary cover.

  7. Hepatic abscess secondary to a rosemary twig migrating from the stomach into the liver

    OpenAIRE

    Karamarkovic, Aleksandar R; Djuranovic, Srdjan P; Popovic, Nada P; Bumbasirevic, Vesna D; Sijacki, Ana D; Blazic, Ivan V

    2007-01-01

    The ingestion of a foreign body that penetrates the gastric wall and migrates to the liver, where it causes an abscess is uncommon. A case of an ingested rosemary twig perforating the gastric antrum, then migrating to the liver, complicated by hepatic abscess and Staphylococcus aureus sepsis is reported. A 59-year-old man without a history of foreign body ingestion was admitted to our hospital because of sepsis and epigastralgia, which had progressively worsened. No foreign body was identifie...

  8. Influence of Aerosol Acidity on the Formation of Secondary Organic Aerosol from Biogenic Precursor Hydrocarbons

    Science.gov (United States)

    Secondary organic aerosol (SOA) formation and dynamics may be important factors for the role of aerosols in adverse health effects, visibility and climate change. Formation of SOA occurs when a parent volatile organic compound is oxidized to create products that form in a conden...

  9. Evaluation des bassins par modélisation intégrée en deux dimensions des transferts techniques, de l'écoulement des fluides, de la genèse et de la migration des hydrocarbures Basin Evaluation by Integrated Two-Dimensional Modeling of Heat Transfer, Fluid Flow, Hydrocarbon Generation, and Migration

    Directory of Open Access Journals (Sweden)

    Chenet P. Y.

    2006-11-01

    Full Text Available Le modèle de bassin exposé dans cet article décrit les phénomènes physiques et chimiques qui contrôlent la formation d'accumulations commerciales, dans le cadre évolutif d'un bassin sédimentaire affecté par la subsidence : transfert de chaleur, compaction et écoulement de l'eau, génèse des hydrocarbures, migration diphasique de l'eau et des hydrocarbures. Le modèle tient compte des variations de conductivité et des phénomènes thermiques transitoires pour reconstituer les paléo-températures. Des validations quantitatives de la reconstitution des paléo-températures et du modèle cinétique de formation des hydrocarbures peuvent être obtenues par comparaison avec les températures actuelles et les données géochimiques. Les écoulements et les surpressions induits par la compaction sont décrits en couplant une loi de compaction avec la loi de Darcy, classique pour les écoulements de l'eau, en ajoutant un critère de fracturation hydraulique naturelle. Ceci permet de modéliser les pressions anormales dans des séquences deltaïques récentes (delta de la Mahakam, comme dans des bassins liés à des rifts anciens (mer du Nord. Une adaptation de la loi de Darcy aux écoulements diphasiques permet de reproduire la migration primaire et la migration secondaire. En particulier, le modèle permet d'étudier le rôle des pressions anormales et l'influence des failles sur la migration et le piégeage. Nos résultats confirment que les modèles de bassins peuvent contribuer à synthétiser les données géologiques, géophysiques et géochimiques dans un schéma cohérent. En précisant l'évaluation pétrolière, ces modèles constituent une des principales voies pour améliorer l'efficacité de l'exploration. The basin model discussed in this paper describes the physical and chemical phenomena that control the formation of commercial accumulations of hydrocarbons in the moving framework of a subsiding sedimentary basin : heat transfer, compaction and water flow, hydrocarbon generation, and two-phase migration of fluids. The model reproduces the influence of conductivity variations and of transient heat transfer on paleotemperatures. Quantitative verification of the paleotemperature reconstruction and of the kinetic model of hydrocarbon generation may be obtained from present temperatures and geochemical data. Compaction-driven flows and overpressures are described by coupling a compaction law with Darcy's law for water flow and a criterion for natural hydraulic fracturing. This formulation allows modeling of overpressures in young deltalic sequences (e. g. , the Mahakam delta, Indonesia as well as in old rift basins (e. g. , the North Sea. An adapted two-phase Darcy's law reproduces primary and secondary migration. In particular, the model helps investigate the role of overpressures and fault behavior on hydrocarbon migration and entrapment. Our results confirm that basin models contribute to the synthesis of geological, geophysical, and geochemical data consistently. By defining parameters for petroleum evaluations, these models increase exploration efficiency.

  10. A 4D Synchrotron X-Ray-Tomography Study of the Formation of Hydrocarbon- Migration Pathways in Heated Organic-Rich Shale

    Energy Technology Data Exchange (ETDEWEB)

    Hamed Panahi; Paul Meakin; Francois Renard; Maya Kobchenko; Julien Scheibert; Adriano Mazzini; Bjorn Jamtveit; Anders Malthe-Sorenssen; Dag Kristian Dysthe

    2013-04-01

    Recovery of oil from oil shales and the natural primary migration of hydrocarbons are closely related processes that have received renewed interest in recent years because of the ever tightening supply of conventional hydrocarbons and the growing production of hydrocarbons from low-permeability tight rocks. Quantitative models for conversion of kerogen into oil and gas and the timing of hydrocarbon generation have been well documented. However, lack of consensus about the kinetics of hydrocarbon formation in source rocks, expulsion timing, and how the resulting hydrocarbons escape from or are retained in the source rocks motivates further investigation. In particular, many mechanisms have been proposed for the transport of hydrocarbons from the rocks in which they are generated into adjacent rocks with higher permeabilities and smaller capillary entry pressures, and a better understanding of this complex process (primary migration) is needed. To characterize these processes, it is imperative to use the latest technological advances. In this study, it is shown how insights into hydrocarbon migration in source rocks can be obtained by using sequential high-resolution synchrotron X-ray tomography. Three-dimensional images of several immature "shale" samples were constructed at resolutions close to 5 um. This is sufficient to resolve the source-rock structure down to the grain level, but very-fine-grained silt particles, clay particles, and colloids cannot be resolved. Samples used in this investigation came from the R-8 unit in the upper part of the Green River shale, which is organic rich, varved, lacustrine marl formed in Eocene Lake Uinta, USA. One Green River shale sample was heated in situ up to 400 degrees C as X-ray-tomography images were recorded. The other samples were scanned before and after heating at 400 degrees C. During the heating phase, the organic matter was decomposed, and gas was released. Gas expulsion from the low-permeability shales was coupled with formation of microcracks. The main technical difficulty was numerical extraction of microcracks that have apertures in the 5- to 30-um range (with 5 um being the resolution limit) from a large 3D volume of X-ray attenuation data. The main goal of the work presented here is to develop a methodology to process these 3D data and image the cracks. This methodology is based on several levels of spatial filtering and automatic recognition of connected domains. Supportive petrographic and thermogravimetric data were an important complement to this study. An investigation of the strain field using 2D image correlation analyses was also performed. As one application of the 4D (space + time) microtomography and the developed workflow, we show that fluid generation was accompanied by crack formation. Under different conditions, in the subsurface, this might provide paths for primary migration.

  11. La migration des hydrocarbures dans les bassins sédimentaires: aspects géologiques et géochimiques Migration of Hydrocarbons in Sedimentary Basins: Geological and Geochemical Aspects

    OpenAIRE

    Tissot B. P.

    2006-01-01

    La migration du pétrole vers les réservoirs et les pièges, et particulièrement son expulsion hors de la roche-mère où il s'est formé (migration primaire), est demeurée longtemps un des problèmes les plus mal connus de toute la géologie pétrolière. Le déplacement du pétrole et du gaz s'effectue en phase hydrocarbure séparée. L'eau, souvent considérée comme le véhicule du pétrole dans la migration, joue en fait un rôle négatif : il faut que la saturation en eau ait suffisamment diminué (par exp...

  12. Global modeling of secondary organic aerosol formation from aromatic hydrocarbons: high- vs. low-yield pathways

    OpenAIRE

    Henze, D. K.; Seinfeld, J.H.; Ng, N. L.; Kroll, J. H.; Fu, T.-M.; Jacob, D. J.; Heald, C. L.

    2008-01-01

    Formation of SOA from the aromatic species toluene, xylene, and, for the first time, benzene, is added to a global chemical transport model. A simple mechanism is presented that accounts for competition between low and high-yield pathways of SOA formation, wherein secondary gas-phase products react further with either nitric oxide (NO) or hydroperoxy radical (HO2) to yield semi- or non-volatile products, respectively. Aromatic species yield more SOA when they react with OH in regio...

  13. Global Modeling of Secondary Organic Aerosol Formation from Aromatic Hydrocarbons: High- vs. Low-Yield Pathways

    OpenAIRE

    Henze, D. K.; Seinfeld, J.H.; Ng, N. L.; Kroll, J. H.; Fu, Tian-Ming; Daniel J. Jacob; Heald, C. L.

    2008-01-01

    Formation of SOA from the aromatic species toluene, xylene, and, for the first time, benzene, is added to a global chemical transport model. A simple mechanism is presented that accounts for competition between low and high-yield pathways of SOA formation, wherein secondary gas-phase products react further with either nitric oxide (NO) or hydroperoxy radical \\((HO_2)\\) to yield semi- or non-volatile products, respectively. Aromatic species yield more SOA when they react with OH in regions whe...

  14. Fluids in the Palaeogene Formation of Gaoyou Sag in the Southern Part of North Jiangsu Basin, China: Evidence for Hydrocarbon Migration and Accumulation

    Science.gov (United States)

    LI, M.; Lou, Z.; Zhu, R.; Jin, A.

    2013-12-01

    Gaoyou Sag, lying in the middle of the Dongtai Depression in the North Jiangsu basin, China, has a well developed fault system and is characterised by structurally complicated oil and gas fields. Its oil-water relationship is very complicated. In the present study, we present the distribution of formation water chemistry, crude oil density, formation pressures and fluid potential in the Palaeogene formation of the Gaoyou Sag . The purpose of this article is to: (1) analyse the cause of hydrochemical diversity; (2) identify the flow pattern and evolution; and (3) understand the interplay between the flow of formation water and hydrocarbon migration and accumulation. The results showed that large variances in formation water chemistry occur in different oilfields of the Gaoyou Sag (Figure 1) due to dilution by meteoric water recharge, concentration by membrane filtration and complexity of geological structure. The low salinity (mean values from 8.53 g/L to 9.67 g/L) of the formation water and heavy crude oil density (up to 0.94g/cm3) in the Xuchuang oilfield indicate influence from meteoric water infiltration; the deep depression areas are mainly of connate origin. Geofluids in the Xuchuang, Zhenwu and Yang'an oilfields mainly flow vertically through the Zhenwu and Hanliu faults, while geofluids in the Shanian oilfield mainly migrate laterally through the reservoirs and are adjusted vertically along some cutting faults. Palaeo-hydrodynamic evolution had an affinity with the generation, migration, accumulation and preservation of hydrocarbons. In the depositional stages of the Dainan and Sanduo formations, formation water was expelled outward and upward from lacustrine mudstones of the deep depression into shallow sands of nearby oilfields, driven by compaction and overpressure. Hydrocarbon migrated with formation water and gathered in appropriate traps, forming primary reservoirs. During the Zhenwu and Sanduo movements, there were tectonic uplifts and the strata suffered denudation. Meteoric water infiltrated inward and downward along active faults and denudated strata, meaning the original oil and gas pools suffered oxidation, damage and even loss. Figure 1 Vertical distribution of total dissolved solids (TDS) of formation water in the Xuchuang, Zhenwu, Yang'an and Shanian oilfields. (A) Location of those four oilfields in the N-S cross section shown in Figure 1; (B) TDS values of those four oilfields vary differently with burial depth.

  15. La migration des hydrocarbures dans les bassins sédimentaires: aspects géologiques et géochimiques Migration of Hydrocarbons in Sedimentary Basins: Geological and Geochemical Aspects

    Directory of Open Access Journals (Sweden)

    Tissot B. P.

    2006-11-01

    Full Text Available La migration du pétrole vers les réservoirs et les pièges, et particulièrement son expulsion hors de la roche-mère où il s'est formé (migration primaire, est demeurée longtemps un des problèmes les plus mal connus de toute la géologie pétrolière. Le déplacement du pétrole et du gaz s'effectue en phase hydrocarbure séparée. L'eau, souvent considérée comme le véhicule du pétrole dans la migration, joue en fait un rôle négatif : il faut que la saturation en eau ait suffisamment diminué (par expulsion et que la saturation en hydrocarbures ait suffisamment augmenté (par génération à partir du kérogène pour que l'écoulement d'une phase hydrocarbure devienne possible. Le moteur de cette expulsion est le gradient de pression : l'élévation de la pression dans l'espace poreux des roches-mères résulte de trois causes (la charge sédimentaire, la genèse des hydrocarbures, et l'expansion thermique de l'eau. La microfissuration, qui survient quand la pression interne des fluides dépasse la résistance mécanique de la roche peut jouer un rôle important. Les observations dans les bassins sédimentaires de cas bien documentés sont encore trop rares. Il est, en particulier, difficile de calculer les réserves mobilisées à l'échelle d'un permis ou d'un bassin. La modélisation numérique de la migration, associée à celle de la genèse du pétrole et du gaz, offre des perspectives dans ce sens, mais elle demande encore des travaux complémentaires. Parmi les conséquences de la migration, on peut citer : la possibilité de corrélation huile/roche-mère, la teneur plus faible en produits lourds dans les réservoirs que dans les roches-mères et le rôle souvent joué par un déplacement où hydrocarbures liquides et gazeux forment une phase unique, qui migre en laissant progressivement derrière elle les fractions plus lourdes, par condensation rétrograde. Oil migration toward reservoirs and traps, and especially its expulsion from the source rock where it was formed (primary migration, has long remained one of the least well understood problems in all petroleum geology. The displacement of oil and gas occurs in a separate hydrocarbon phase. Water, which is often considered as the vehicle for oil during migration, effectively plays a negative role. Water saturation must have been sufficiently diminished (by expulsion and hydrocarbon saturation must be sufficiently increased (by generation from kerogen for the flow of a hydrocarbon phase to become possible. The driving force for this expulsion is the pressure gradient. A rise in pressure in the pore volume of source rocks results from three causes (the sedimentary load, the formation of hydrocarbons, and the thermal expansion of water. Microfracturing, which occurs when the internal pressure of fluids exceeds the mechanical strength of the rock, may play an important role. Observations of well documented cases in sedimentary basins are still too rare. In particular, it is difficult to compute the reserves mobilized on the scale of a permit or basin. The numerical modeling of migration combined with that of the formation of oil and gas opens up perspectives in this direction, but it still requires further work. Among the consequences of migration, mention can be made of the possibility of oil/source-rock correlation, the lower content of heavy products in reservoirs than in source rocks, and the role often played by a displacement in which liquid and gaseous hydrocarbons form a single phase that migrates while progressively leaving the heavier fractions behind it, by retrograde condensation.

  16. Global modeling of secondary organic aerosol formation from aromatic hydrocarbons: high- vs. low-yield pathways

    Directory of Open Access Journals (Sweden)

    D. K. Henze

    2008-05-01

    Full Text Available Formation of SOA from the aromatic species toluene, xylene, and, for the first time, benzene, is added to a global chemical transport model. A simple mechanism is presented that accounts for competition between low and high-yield pathways of SOA formation, wherein secondary gas-phase products react further with either nitric oxide (NO or hydroperoxy radical (HO2 to yield semi- or non-volatile products, respectively. Aromatic species yield more SOA when they react with OH in regions where the [NO]/[HO2] ratios are lower. The SOA yield thus depends upon the distribution of aromatic emissions, with biomass burning emissions being in areas with lower [NO]/[HO2] ratios, and the reactivity of the aromatic with respect to OH, as a lower initial reactivity allows transport away from industrial source regions, where [NO]/[HO2] ratios are higher, to more remote regions, where this ratio is lower and, hence, the ultimate yield of SOA is higher. As a result, benzene is estimated to be the most important aromatic species with regards to global formation of SOA, with a total production nearly equal that of toluene and xylene combined. Global production of SOA from aromatic sources via the mechanisms identified here is estimated at 3.5 Tg/yr, resulting in a global burden of 0.08 Tg, twice as large as previous estimates. The contribution of these largely anthropogenic sources to global SOA is still small relative to biogenic sources, which are estimated to comprise 90% of the global SOA burden, about half of which comes from isoprene. Uncertainty in these estimates owing to factors ranging from the atmospheric relevance of chamber conditions to model deficiencies result in an estimated range of SOA production from aromatics of 2–12 Tg/yr. Though this uncertainty range affords a significant anthropogenic contribution to global SOA, it is evident from comparisons to recent observations that additional pathways for production of anthropogenic SOA still exist beyond those accounted for here. Nevertheless, owing to differences in spatial distributions of sources and seasons of peak production, regions exist in which aromatic SOA produced via the mechanisms identified here are predicted to contribute substantially to, and even dominate, the local SOA concentrations, such as outflow regions from North America and South East Asia during the wintertime, though total modeled SOA concentrations there are small (~0.1 ?g/m3.

  17. Global modeling of secondary organic aerosol formation from aromatic hydrocarbons: high- vs low-yield pathways

    Directory of Open Access Journals (Sweden)

    D. K. Henze

    2007-10-01

    Full Text Available Formation of SOA from the aromatic species toluene, xylene, and, for the first time, benzene, is added to a global chemical transport model. A simple mechanism is presented that accounts for competition between low and high-yield pathways of SOA formation, wherein secondary gas-phase products react further with either nitrogen oxide (NO or hydroperoxy radical (HO2 to yield semi- or non-volatile products, respectively. Aromatic species yield more SOA when they react with OH in regions where the [NO]/[HO2] ratios are lower. The SOA yield thus depends upon the distribution of aromatic emissions, with biomass burning emissions being in areas with lower [NO]/[HO2] ratios, and the reactivity of the aromatic with respect to OH, as a lower initial reactivity allows transport away from industrial source regions, where [NO]/[HO2] ratios are higher, to more remote regions, where this ratio is lower and, hence, the ultimate yield of SOA is higher. As a result, benzene is estimated to be the most important aromatic species with regards to formation of SOA, with a total production nearly equal that of toluene and xylene combined. In total, while only 39% percent of the aromatic species react via the low-NOx pathway, 72% of the aromatic SOA is formed via this mechanism. Predicted SOA concentrations from aromatics in the Eastern United States and Eastern Europe are actually largest during the summer, when the [NO]/[HO2] ratio is lower. Global production of SOA from aromatic sources is estimated at 3.5 Tg/yr, resulting in a global burden of 0.08 Tg, twice as large as previous estimates. The contribution of these largely anthropogenic sources to global SOA is still small relative to biogenic sources, which are estimated to comprise 90% of the global SOA burden, about half of which comes from isoprene. Compared to recent observations, it would appear there are additional pathways beyond those accounted for here for production of anthropogenic SOA. However, owing to differences in spatial distributions of sources and seasons of peak production, there are still regions in which aromatic SOA produced via the mechanisms identified here are predicted to contribute substantially to, and even dominate, the local SOA concentrations, such as outflow regions from North America and South East Asia during the wintertime, though total SOA concentrations there are small (~0.1 ?g/m³.

  18. The Feminisation of Migration and the Migrants VET Policy Neglects: The Case of Skilled Women Secondary Migrants in Australia

    Science.gov (United States)

    Webb, Sue

    2015-01-01

    There is increasingly scholarship on gender and migration, yet the international migration of highly skilled women is still somewhat under-researched. This article focuses on this neglected area in the context of Australia's discretionary inward migration policies to solve skills shortages. The article draws on empirical research using a…

  19. Petroleum geochemistry of the Froy field and Rind discovery, Norwegian Continental Shelf. Implications for reservoir characterization, compartmentalization and basin scale hydrocarbon migration patterns in the region

    Energy Technology Data Exchange (ETDEWEB)

    Bhullar, A.G.; Karlsen, D.A.; Backer-Owe, K. [University of Oslo (Norway). Petroleum Geochemistry Program; Holm, K. [Elf Petroleum Norge asa, Stavanger (Norway); Le Tran, K. [Elf Aquitaine Production, Pau Cedex (France)

    1998-12-31

    Petroleum geochemistry provides an excellent tool for understanding reservoir characteristics with respect to oil flow and tracing out elements of basin scale migrational patterns and reservoir compartmentalization. Organic geochemical characterization has been carried out on 580 core extracts and 9 oils from 11 wells of the Froy field and Rind discovery in the South Viking Graben. Two different drainage areas and source rock systems have been identified for the hydrocarbons in the Froy field and the Rind discovery on the basis of differences in maturity and gas to oil ratio in addition to facies differences like % C{sub 28}-{alpha}{alpha}-sterane content and the ratio of bisnorhopane to bisnorhopane plus norhopane. Results show that the Rind discovery contains oil of higher maturity compared to the oil from Froy field. The petroleum in the Rind discovery has a more terrestrial character and is interpreted to have been derived from source rocks other than the Daupne Formation in its typical anoxic distal development. A likely candidate is the Heather Formation. In addition, a small contribution of immature oil has been identified in a separate mall sub-compartment in the Froy field. To conclude, there is no petroleum geochemical evidence to suggest that intra-reservoir faults have caused significant compartmentalization of the Froy field except for the N-S trending fault which separates a small block to the west from the Froy field main reservoir. Thus with respect to petroleum production, it is concluded that primary sedimentological features are more important in terms of exerting a first order control for determining the vertical and lateral flow of hydrocarbons in this reservoir than faults. (author)

  20. Microbial Oxidation of Gaseous Hydrocarbons: Production of Secondary Alcohols from Corresponding n-Alkanes by Methane-Utilizing Bacteria

    OpenAIRE

    Patel, Ramesh N.; Hou, C. T.; Laskin, A I; Felix, A; Derelanko, P.

    1980-01-01

    Over 20 new strains of methane-utilizing bacteria were isolated from lake water and soil samples. Cell suspensions of these and of other known strains of methane-utilizing bacteria oxidized n-alkanes (propane, butane, pentane, hexane) to their corresponding secondary alcohols (2-propanol, 2-butanol, 2-pentanol, 2-hexanol). The product secondary alcohols accumulated extracellularly. The rate of production of secondary alcohols varied with the organism used for oxidation. The average rate of 2-...

  1. Secondary effects of catalytic diesel particulate filters: reduced aryl hydrocarbon receptor-mediated activity of the exhaust.

    Science.gov (United States)

    Wenger, Daniela; Gerecke, Andreas C; Heeb, Norbert V; Zennegg, Markus; Kohler, Martin; Naegeli, Hanspeter; Zenobi, Renato

    2008-04-15

    Diesel exhaust contains numerous toxic substances that show different modes of action such as triggering aryl hydrocarbon receptor (AhR)-mediated pathways. We investigated AhR-mediated activity of exhaust generated by a heavy-duty diesel engine operated with or without iron- or copper/iron-catalyzed diesel particulate filters (DPFs). AhR agonists were quantified using the DR-CALUX reporter gene assay (exposure of cells for 24 h). We found 54-60 ng 2,3,7,8-tetrachlorodibenzo-p-dioxin CALUX equivalents (TCDD-CEQs) per m3 of exhaust in unfiltered samples and 6-16 ng TCDD-CEQ m3 in DPF-treated samples. DPF applications decreased TCDD-CEQ concentrations by almost 90%. Concentrations of known AhR agonists were determined with GC/HRMS and converted to TCDD-CEQ concentrations using compound-specific relative potency values. The analyzed nine polycyclic aromatic hydrocarbons (PAHs) and the 172,3,7,8-chlorinated dibenzodioxins/furans (23,7,8-PCDD/Fs) contributed only marginally (0.6-1.6%) to the total agonist concentration. However, both DPFs also decreased concentrations of individual PAHs by 7(0-80%. Variation of the assay exposure time (8, 24, 48,72, and 96 h) revealed that AhR-mediated activity decreased over time and reached a plateau after 72 h, which was most likely due to biotransformation of AhR agonists by the exposed H4IIE cells. At the plateau, we measured 1-2 ng TCDD-CEQ m(-3) in both an unfiltered and a filtered exhaust sample. Our findings show that DPFs are a promising technology to detoxify diesel exhaust regarding compounds with AhR-mediated activity. PMID:18497156

  2. Hydrocarbon pneumonia

    Science.gov (United States)

    Pneumonia - hydrocarbon ... Coughing Fever Shortness of breath Smell of a hydrocarbon product on the breath Stupor (decreased level of ... Most children who drink or inhale hydrocarbon products and develop ... hydrocarbons may lead to rapid respiratory failure and death.

  3. Polynuclear aromatic hydrocarbon and particulate emissions from two-stage combustion of polystyrene: the effects of the secondary furnace (afterburner) temperature and soot filtration.

    Science.gov (United States)

    Wang, Jun; Richter, Henning; Howard, Jack B; Levendis, Yiannis A; Carlson, Joel

    2002-02-15

    Laboratory experiments were conducted in a two-stage horizontal muffle furnace in order to monitor emissions from batch combustion of polystyrene (PS) and identify conditions that minimize them. PS is a dominant component of municipal and hospital waste streams. Bench-scale combustion of small samples (0.5 g) of shredded styrofoam cups was conducted in air, using an electrically heated horizontal muffle furnace, kept at Tgas = 1000 degrees C. Upon devolatilization, combustion of the polymer took place in a diffusion flame over the sample. The gaseous combustion products were mixed with additional air in a venturi and were channeled to a secondary muffle furnace (afterburner) kept at Tgas = 900-1100 degrees C; residence time therein varied between 0.6 and 0.8 s. At the exits of the primary and the secondary furnace the emissions of CO, CO2, O2, NOx, particulates as well as volatile and semivolatile hydrocarbons, such as polycyclic aromatic hydrocarbons (PAH), were monitored. Online analyzers, gravimetric techniques, and gas chromatography coupled to mass spectrometry (GC-MS) were used. Experiments were also conducted with a high-temperature barrier filter, placed just before the exit of the primary furnace to prevent the particulates from entering into the secondary furnace. Results demonstrated the beneficial effect of the afterburner in reducing PAH concentrations, including those of mutagenic species such as benzo[a]pyrene. Concentrations of individual PAH exhibited a pronounced after burner temperature dependence, typically ranging from a small decrease at 900 degrees C to a larger degree of consumption at 1100 degrees C. Consumption of PAH was observed to be the dominant feature at 900 degrees C, while significant quantities of benzene and some of its derivatives, captured by means of carbosieve/Carbotrap adsorbents, were formed in the afterburner at a temperature of 1000 degrees C. In the primary furnace, about 30% of the mass of the initial polystyrene was converted into soot, while the total mass of PAH represented about 3% of the initial mass of combustible. The afterburner reduced the particulate (soot) emissions by only 20-30%, which indicates that once soot is formed its destruction is rather difficult because its oxidation kinetics are slow undertypical furnace conditions. Moreover, increasing the afterburnertemperature resulted in an increasing trend of soot emissions therefrom, which might indicate competition between soot oxidation and formation, with some additional formation occurring at the higher temperatures. Contrary to the limited effect of the afterburner, high-temperature filtration of the combustion effluent prior to the exit of the primary furnace allowed for effective soot oxidation inside of the ceramic filter. Filtration drastically reduced soot emissions, by more than 90%. Limited soot formation in the afterburner was again observed with increasing temperatures. The yields of both CO and CO2 were largely unaffected by the temperature of the afterburner but increased at the presence of the filter indicating oxidation therein. A previously developed kinetic model was used to identify major chemical reaction pathways involving PAH in the afterburner. The experimental data at the exit of the primary furnace was used as input to these model computations. A first evaluation of the predictive capability of the model was conducted for the case with ceramic filter and a temperature of 900 degrees C. The afterburner was approximated as a plug-flow reactor, and model predictions at a residence time of 0.8 s were compared to experimental data collected at its exit. In agreement with the experimental PAH concentration, only a minor impact of the afterburner treatment was observed for most species at 900 degrees C. OH was deduced to be the major reactant with a mole fraction about 4 orders of magnitudes higher than that of hydrogen radicals. Evidence for the need of further work on the quantitative assessment of oxidation of PAH and their radicals is given. PMID:11878400

  4. Oil-bearing inclusions in vein quartz and kalcite and, bitumens in veins: Testament to multiple phases of hydrocarbon migration in the Barrandian basin (lower Palaeozoic), Czech Republic.

    Czech Academy of Sciences Publication Activity Database

    Suchý, V.; Dobeš, P.; Sýkorová, Ivana; Machovi?, Vladimír; Stejskal, M.; Kroužek, J.; Chudoba, J.; Mat?jovský, L.; Havelcová, Martina; Matysová, Petra

    2010-01-01

    Ro?. 27, ?. 1 (2010), s. 285-297. ISSN 0264-8172 R&D Projects: GA AV ?R(CZ) IAA3012703; GA AV ?R IAA300460804 Institutional research plan: CEZ:AV0Z30460519 Keywords : hydrocarbon * fluid inclusion * bitumen Subject RIV: DD - Geochemistry Impact factor: 2.130, year: 2010

  5. Polycyclic aromatic hydrocarbon (PAH)-mediated upregulation of hepatic microRNA-181 family promotes cancer cell migration by targeting MAPK phosphatase-5, regulating the activation of p38 MAPK

    Energy Technology Data Exchange (ETDEWEB)

    Song, Mi-Kyung [Center for Integrated Risk Research, Cellular and Molecular Toxicology Laboratory, Korea Institute of Science and Technology (KIST) (Korea, Republic of); School of Life Sciences and Biotechnology, Korea University, Anam-Dong, Seoungbuk-Gu, Seoul 136-701 (Korea, Republic of); Park, Yong-Keun [School of Life Sciences and Biotechnology, Korea University, Anam-Dong, Seoungbuk-Gu, Seoul 136-701 (Korea, Republic of); Ryu, Jae-Chun, E-mail: ryujc@kist.re.kr [Center for Integrated Risk Research, Cellular and Molecular Toxicology Laboratory, Korea Institute of Science and Technology (KIST) (Korea, Republic of)

    2013-11-15

    Growing evidence indicates that changes in microRNA (miRNA) expression in cancer induced by chemical carcinogens play an important role in cancer development and progression by regulating related genes. However, the mechanisms underlying miRNA involvement in hepatocarcinogenesis induced by polycyclic aromatic hydrocarbons (PAHs) remain unclear. Thus, the identification of aberrant miRNA expression during PAH-induced cancer cell migration will lead to a better understanding of the substantial role of miRNAs in cancer progression. In the present study, miRNA expression profiling showed significant upregulation of miR-181a, -181b, and -181d in human hepatocellular carcinoma cells (HepG2 line) exposed to benzo[a]anthracene (BA) and benzo[k]fluoranthene (BF). MAPK phosphatase-5 (MKP-5), a validated miR-181 target that deactivates MAPKs, was markedly suppressed while phosphorylation of p38 MAPK was increased after BA and BF exposure. The migration of HepG2 cells, observed using the scratch wound-healing assay, also increased in a dose-dependent manner. Depletion of miR-181 family members by miRNA inhibitors enhanced the expression of MKP-5 and suppressed the phosphorylation of p38 MAPK. Furthermore, the depletion of the miR-181 family inhibited cancer cell migration. Based on these results, we conclude that the miR-181 family plays a critical role in PAH-induced hepatocarcinogenesis by targeting MKP-5, resulting in the regulation of p38 MAPK activation. - Highlights: • We found significant upregulation of miR-181 family in HCC exposed to BA and BF. • We identified the MKP-5 as a putative target of miR-181 family. • MKP-5 was suppressed while p-P38 was increased after BA and BF exposure. • The migration of HepG2 cells increased in a dose-dependent manner.

  6. Litiasis vesical secundaria a migración de dispositivo intrauterino: Reporte de un caso / Bladder lithiasis secondary to intrauterine device migration: Case report

    Scientific Electronic Library Online (English)

    Tomás Lázaro, Rodríguez Collar; Yamel, Gil del Valle; Basily, Valdés Estévez; Víctor Osvaldo, Barquín Carmona; José Antonio, García Monzón.

    2008-06-01

    Full Text Available Objetivo: Presentar un caso clínico de litiasis vesical secundaria a la migración de un dispositivo intrauterino, su sintomatología, los medios empleados para su diagnóstico y el tratamiento aplicado. Método/Resultado. Paciente de 30 años de edad, que al cabo del año de colocársele un dispositivo in [...] trauterino (T de cobre), luego de interrupción de embarazo mediante legrado endometrial, comenzó a presentar síntomas urinarios irritativos bajos. Se le trató durante dos años como si tuviese cistitis infecciosa con varios ciclos de diferentes antibióticos. Por la persistencia de las molestias asiste a la consulta de Urología, y se le detecta, mediante ultrasonido y radiografía ántero-posterior de la pelvis, una litiasis intravesical de cinco por tres centímetros de tamaño, con una T de cobre en su interior. Se le realizó la cistolitotomía suprapúbica, presentando una buena evolución y regresión total de los síntomas. Conclusión. La migración de un dispositivo intrauterino a la vejiga, es una causa infrecuente de litiasis vesical secundaria a cuerpo extraño. No obstante, debemos pensar en esta posibilidad ante la cronicidad de síntomas urinarios irritativos bajos, en toda mujer que emplee este método anticonceptivo. Abstract in english Objective: To report one clinical case of bladder lithiasis secondary to the migration of an intrauterine device, its symptoms, diagnostic tests employed and treatment. Methods/Results: 30 year old female patient who presented lower urinary tract irritative symptoms. One year before she underwent in [...] sertion of an intrauterine device (copper T) after endometrial curettage for pregnancy interruption. She received treatment for infection cystitis over two years, with various antibiotic cycles. The persistence of symptoms led her to the urology clinics, and a 5x 3 cm intravesical lithiasis with a copper T inside was detected by ultrasound and pelvic anterior-posterior x-ray. Suprapubic cystolithotomy was performed with a good outcome and disappearance of the symptoms. Conclusions: The migration of an intrauterine device to the bladder is an unfrequent cause of bladder lithiasis secondary to foreign body. Nevertheless, we must consider this possibility in front of chronic lower urinary tract irritative symptoms in every female using this birth control method.

  7. The evolution of Devonian hydrocarbon gases in shallow aquifers of the northern Appalachian Basin: Insights from integrating noble gas and hydrocarbon geochemistry

    Science.gov (United States)

    Darrah, Thomas H.; Jackson, Robert B.; Vengosh, Avner; Warner, Nathaniel R.; Whyte, Colin J.; Walsh, Talor B.; Kondash, Andrew J.; Poreda, Robert J.

    2015-12-01

    The last decade has seen a dramatic increase in domestic energy production from unconventional reservoirs. This energy boom has generated marked economic benefits, but simultaneously evoked significant concerns regarding the potential for drinking-water contamination in shallow aquifers. Presently, efforts to evaluate the environmental impacts of shale gas development in the northern Appalachian Basin (NAB), located in the northeastern US, are limited by: (1) a lack of comprehensive "pre-drill" data for groundwater composition (water and gas); (2) uncertainty in the hydrogeological factors that control the occurrence of naturally present CH4 and brines in shallow Upper Devonian (UD) aquifers; and (3) limited geochemical techniques to quantify the sources and migration of crustal fluids (specifically methane) at various time scales. To address these questions, we analyzed the noble gas, dissolved ion, and hydrocarbon gas geochemistry of 72 drinking-water wells and one natural methane seep all located ≫1 km from shale gas drill sites in the NAB. In the present study, we consciously avoided groundwater wells from areas near active or recent drilling to ensure shale gas development would not bias the results. We also intentionally targeted areas with naturally occurring CH4 to characterize the geochemical signature and geological context of gas-phase hydrocarbons in shallow aquifers of the NAB. Our data display a positive relationship between elevated [CH4], [C2H6], [Cl], and [Ba] that co-occur with high [4He]. Although four groundwater samples show mantle contributions ranging from 1.2% to 11.6%, the majority of samples have [He] ranging from solubility levels (∼45 × 10-6 cm3 STP/L) with below-detectable [CH4] and minor amounts of tritiogenic 3He in low [Cl] and [Ba] waters, up to high [4He] = 0.4 cm3 STP/L with a purely crustal helium isotopic end-member (3He/4He = ∼0.02 times the atmospheric ratio (R/Ra)) in samples with CH4 near saturation for shallow groundwater (P(CH4) = ∼1 atmosphere) and elevated [Cl] and [Ba]. These data suggest that 4He is dominated by an exogenous (i.e., migrated) crustal source for these hydrocarbon gas- and salt-rich fluids. In combination with published inorganic geochemistry (e.g., 87Sr/86Sr, Sr/Ba, Br-/Cl-), new noble gas and hydrocarbon isotopic data (e.g., 20Ne/36Ar, C2+/C1, δ13C-CH4) suggest that a hydrocarbon-rich brine likely migrated from the Marcellus Formation (via primary hydrocarbon migration) as a dual-phase fluid (gas + liquid) and was fractionated by solubility partitioning during fluid migration and emplacement into conventional UD traps (via secondary hydrocarbon migration). Based on the highly fractionated 4He/CH4 data relative to Marcellus and UD production gases, we propose an additional phase of hydrocarbon gas migration where natural gas previously emplaced in UD hydrocarbon traps actively diffuses out into and equilibrates with modern shallow groundwater (via tertiary hydrocarbon migration) following uplift, denudation, and neotectonic fracturing. These data suggest that by integrating noble gas geochemistry with hydrocarbon and dissolved ion chemistry, one can better determine the source and migration processes of natural gas in the Earth's crust, which are two critical factors for understanding the presence of hydrocarbon gases in shallow aquifers.

  8. Influence of organic matter and clay minerals in migration of derivative compounds of hydrocarbons; Influencia da materia organica e argilominerais na migracao de compostos derivados de hidrocarbonetos

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, Denize Gloria Barcellos; Mendonca Filho, Joao Graciano de; Polivanov, Helena [Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst. de Geociencias. Dept. de Geologia]. E-mail: denize@geologia.ufrj.br; graciano@geologia.ufrj.br; helena@acd.ufrj.br

    2003-07-01

    Soil samples from the Guanabara Bay in Duque de Caxias city (RJ) were submitted to mineralogical and organic geochemistry analyses. This proceeding was used mainly to determine a possible interaction of hydrocarbons contaminants with the organic matter and the clay minerals presents in this mangrove. The sampling was carried out using Direct Push techniques. Thus, the mainly clay minerals characterizes were: gibbsite, illite, caulinite and smectite. The compositional analysis of organic constituents showed a predominance of amorphous material (degraded cuticles), followed of wood material and sporomorphs constituents, suggesting that the biological degradation occurred in situ. (author)

  9. International Migration of Couples

    DEFF Research Database (Denmark)

    Munk, Martin D.; Junge, Martin; Poutvaara, Panu

    2016-01-01

    We develop a theoretical model regarding the migration of dual-earner couples and test it in the context of international migration. Our model predicts that the probability that a couple emigrates increases with the income of the primary earner, whereas the income of the secondary earner may affect...

  10. An open-water electrical geophysical tool for mapping sub-seafloor heavy placer minerals in 3D and migrating hydrocarbon plumes in 4D

    Science.gov (United States)

    Wynn, J.; Williamson, M.; Urquhart, S.; Fleming, J.

    2011-01-01

    A towed-streamer technology has been developed for mapping placer heavy minerals and dispersed hydrocarbon plumes in the open ocean. The approach uses induced polarization (IP), an electrical measurement that encompasses several different surface-reactive capacitive and electrochemical phenomena, and thus is ideally suited for mapping dispersed or disseminated targets. The application is operated at sea by towing active electrical geophysical streamers behind a ship; a wide area can be covered in three dimensions by folding tow-paths over each other in lawn-mower fashion. This technology has already been proven in laboratory and ocean settings to detect IP-reactive titanium-and rare-earth (REE) minerals such as ilmenite and monazite. By extension, minerals that weather and accumulate/concentrate by a similar mechanism, including gold, platinum, and diamonds, may be rapidly detected and mapped indirectly even when dispersed and covered with thick, inert sediment. IP is also highly reactive to metal structures such as pipelines and cables. ?? 2011 MTS.

  11. Benzo[b]naphthothiophenes and alkyl dibenzothiophenes: molecular tracers for oil migration distances

    Science.gov (United States)

    Li, Meijun; Wang, T.-G.; Shi, Shengbao; Liu, Keyu; Ellis, Geoffrey S.

    2014-01-01

    The secondary migration of petroleum is one of the most critical geological processes responsible for the accumulation of hydrocarbons in a sedimentary basin. Pyrrolic nitrogen compounds such as carbazoles and benzocarbazoles are thought to be practical molecular indicators for estimating relative migration distances of oil. In light oils or condensates, however, considerable analytical errors are usually caused by low concentrations of NSO-compounds. Here we show that polycyclic sulfur aromatic hydrocarbons such as dibenzothiophene, C1?C3 alkylated dibenzothiophenes and benzo[b]naphthothiophenes, which are present in relatively higher concentrations than the pyrrolic nitrogen compounds, exhibit changes in both absolute and relative concentrations that correlate with migration distances. The polycyclic sulfur aromatic hydrocarbons related parameters — benzo[b]naphtho[2,1-d]thiophene/{benzo[b]naphtho[2,1-d]thiophene + benzo[b]naphtho[1,2-d]thiophene} (abbreviated as [2,1]BNT/([2,1]BNT+[1,2]BNT) and the concentration of total dibenzothiophenes plus benzo[b]naphthothiophenes — are proposed by this paper to trace the oil migration distances.

  12. Control and assessment of the hydrocarbon contamination of Ukrainian soils

    Science.gov (United States)

    Miroshnichenko, N. N.

    2008-05-01

    Regularities governing the self-purification of soils from oil hydrocarbons, as well as migration of hydrocarbons, and the effect on the water-physical properties and fertility of soils were revealed in a series of experiments. A system of ecological, economic, and reclamation standards was proposed for regulating economic activities in the case of soil contamination with hydrocarbons.

  13. Planet migration

    OpenAIRE

    Thommes, Edward W.; Lissauer, Jack J

    2002-01-01

    Planet migration is the process by which a planet's orbital radius changes in time. The main agent for causing gas giant planet migration is the gravitational interaction of the young planet with the gaseous disk from which it forms. We describe the migration rates resulting from these interactions based on a simple model for disk properties. These migration rates are higher than is reasonable for planet survival. We discuss some proposed models for which the migration rates are lower. There ...

  14. Alkyloxycarbonyl group migration in furanosides

    OpenAIRE

    Dvo?áková, M; P?ibylová, M. (Marie); R. Pohl; Migaud, M. E.; Van?k, T. (Tomáš)

    2012-01-01

    A migration of methyloxycarbonyl group from secondary to primary hydroxyl was observed in furanosides (ribosides and xylosides) under usual desilylation conditions using tetrabutylammonium fluoride. The migration was studied further on several alkyloxycarbonyl furanosides under either basic or acidic conditions. As follows from C-13 labelling experiments and product distribution, the migration in xylosides, proceeds intramolecularly via six-membered cyclic carbonate, whereas in ribosides, the...

  15. MIGRATION AND ITS ENVIROMENTAL EFFECTS

    OpenAIRE

    Saeed, Rashid; Rana NADIR IDREES; Humna IJAZ; Marriam FURQANI; Raziya NADEEM

    2012-01-01

    Migration can be ongoing shifting of a particular person from one location to another. The reason of shifting depends on selected thought deficiency, shock, difficulties, hopes, enthusiasm. Case study ended up recognizing the extent to which in turn migration can be relying on the specifics especially natural environment. This particular document expects to research the actual linkages between the atmosphere as well as migration using secondary data. Lots of investigation may be completed wit...

  16. Future of Secondary Services.

    Science.gov (United States)

    Neufeld, M. Lynne

    1983-01-01

    Argues that the major forces related to economic factors that effect the future of secondary services are growth of primary literature and expansion of secondary products; migration of use from print products to tape products; new technology and impact on production of products and services; and redefinition of user as end user. (EJS)

  17. Apparatus for hydrocarbon extraction

    Science.gov (United States)

    Bohnert, George W.; Verhulst, Galen G.

    2013-03-19

    Systems and methods for hydrocarbon extraction from hydrocarbon-containing material. Such systems and methods relate to extracting hydrocarbon from hydrocarbon-containing material employing a non-aqueous extractant. Additionally, such systems and methods relate to recovering and reusing non-aqueous extractant employed for extracting hydrocarbon from hydrocarbon-containing material.

  18. Transport of petroleum hydrocarbons in permafrost soils

    International Nuclear Information System (INIS)

    A sampling program was conducted to determine the presence and extent of petroleum hydrocarbon contamination in permafrost soils at an abandoned arctic weather station. Core samples were taken of frozen silty clay at two known contaminated sites and analyzed for total petroleum hydrocarbon content. Contamination was observed at depths of 0.5 m into the permafrost. The most influential transport mechanism is likely to be migration of hydrocarbons through cracks, fissures and filled voids in the permafrost soil due to gravity drainage and capillary action. Another possible transport mechanism is by diffusion in unfrozen water within the permafrost. 19 refs., 4 figs

  19. Molecular and carbon isotope compositions of hydrocarbon gas in Neogene sedimentary rocks in Horonobe area, Northern Hokkaido, Japan

    International Nuclear Information System (INIS)

    We conducted headspace gas analyses using cores from two 520 m boreholes to evaluate the gas permeability of Neogene sedimentary rocks in Horonobe, Hokkaido, Japan. Analytical data suggest that most hydrocarbon gases are microbial methane. Further analyses of these data indicated that the low concentration and heavy carbon isotope composition of methane could be explained by carbon isotopic fractionation during migration near fractures. The high residual volume of microbial methane observed in the study area suggests that the sedimentary layers have low gas permeability, and are affected less by secondary post-generation processes. The headspace gas analysis is an effective approach for detecting sedimentary layers having a high confinement capability. (author)

  20. Permian-Triassic maturation and multistage migration of hydrocarbons in the Assistência Formation (Irati Subgroup), Paraná Basin, Brazil: implications for the exploration model / Maturação permotriássica e os vários estágios de migração de hidrocarbonetos na Formação Assistência (Subgrupo Irati), Bacia do Paraná: implicações para os modelos exploratórios

    Scientific Electronic Library Online (English)

    António, Mateus; Claudio, Riccomini; Ezequiel J. E. C. B., Ferreira; Colombo C. G., Tassinari.

    2014-09-01

    Full Text Available Novas linhas de evidências geológicas sugerem fortemente que o principal período de maturação de hidrocarbonetos na Formação Assistência teria ocorrido no Permotriássico, estimulado por um gradiente geotérmico elevado que também sustentou várias manifestações de atividade hidrotermal. Três fases pri [...] ncipais de migração de fluidos e hidrocarbonetos também podem ser inferidas a partir de observações em multiescala: fluxo confinado no final do Permiano ao Triássico, dependente do acúmulo local de pressões de fluidos; fluxo heterogêneo no Cretáceo Inferior, desencadeado por um gradiente de temperatura rejuvenescido, assistido pelas condições de permeabilidade antes desenvolvidas; e um fluxo tardio, possivelmente impulsionado por gradientes de pressão locais, posteriormente ao esfriamento dos diques e soleiras de diabásio. A maturação precoce e a existência de vários estágios de migração de hidrocarbonetos apresentam implicações significativas na concepção de modelos exploratórios a serem aplicados na Bacia do Paraná. Abstract in english New lines of geological evidence strongly suggest that the main period of hydrocarbon maturation within Assistência Formation should be Permian-Triassic, stimulated by a high geothermal gradient that also sustained various manifestations of hydrothermal activity. Three main stages of fluid/hydrocarb [...] on migration can also be inferred on the basis of multiscale observations: confined flow in late Permian to Triassic times, depending on the local build-up of fluid pressures; heterogeneous flow in Lower Cretaceous, triggered by a rejuvenated temperature gradient assisted by the early developed permeability conditions; and a late flow possibly driven by local pressure gradients, after complete cooling of dolerite dykes/sills. The early maturation and multistage migration of hydrocarbons have significant consequences in the design of exploration models to be applied in Paraná Basin.

  1. The hydrocarbon sphere

    Energy Technology Data Exchange (ETDEWEB)

    Mandev, P.

    1984-01-01

    The hydrocarbon sphere is understood to be the area in which hydrocarbon compounds are available. It is believed that the lower boundary on the hydrocarbon sphere is most probably located at a depth where the predominant temperatures aid in the destruction of hydrocarbons (300 to 400 degrees centigrade). The upper limit on the hydrocarbon sphere obviously occurs at the earth's surface, where hydrocarbons oxidize to H20 and CO2. Within these ranges, the occurrence of the hydrocarbon sphere may vary from the first few hundred meters to 15 kilometers or more. The hydrocarbon sphere is divided into the external (mantle) sphere in which the primary gas, oil and solid hydrocarbon fields are located, and the internal (metamorphic) sphere containing primarily noncommercial accumulations of hydrocarbon gases and solid carbon containing compounds (anthraxilite, shungite, graphite, etc.) based on the nature and scale of hydrocarbon compound concentrations (natural gas, oil, maltha, asphalt, asphaltite, etc.).

  2. Migration chemistry

    International Nuclear Information System (INIS)

    Migration chemistry, the influence of chemical -, biochemical - and physico-chemical reactions on the migration behaviour of pollutants in the environment, is an interplay between the actual natur of the pollutant and the characteristics of the environment, such as pH, redox conditions and organic matter content. The wide selection of possible pollutants in combination with varying geological media, as well as the operation of different chemical -, biochemical - and physico-chemical reactions compleactes the prediction of the influence of these processes on the mobility of pollutants. The report summarizes a wide range of potential pollutants in the terrestrial environment as well as a variety of chemical -, biochemical - and physico-chemical reactions, which can be expected to influence the migration behaviour, comprising diffusion, dispersion, convection, sorption/desorption, precipitation/dissolution, transformations/degradations, biochemical reactions and complex formation. The latter comprises the complexation of metal ions as well as non-polar organics to naturally occurring organic macromolecules. The influence of the single types of processes on the migration process is elucidated based on theoretical studies. The influence of chemical -, biochemical - and physico-chemical reactions on the migration behaviour is unambiguous, as the processes apparently control the transport of pollutants in the terrestrial environment. As the simple, conventional KD concept breaks down, it is suggested that the migration process should be described in terms of the alternative concepts chemical dispersion, average-elution-time and effective retention. (AB) (134 refs.)

  3. Petroleum hydrocarbons in detention-basin sediments

    International Nuclear Information System (INIS)

    The present study was conducted to examine petroleum hydrocarbons in the sediments of a storm-water retention basin in central New Jersey. A dry storm-water detention basin, which services a 0.405-km2 condominium development, was used for the investigation. Soil samples were collected following the general pattern of water progression through the basin and analyzed for total petroleum hydrocarbons. The study found petroleum hydrocarbons, being hydrophobic in nature, sorb to particulates that settle and reside in the sediment. Results comparing two successive summer samplings show that levels of petroleum hydrocarbons are maintained in the basin sediments. General trends showed that the hydrocarbon concentrations are a function of depth and proximity to the influent culverts. One soil core was extended to a depth of 15.2 cm. The results show hydrocarbon concentrations decreasing to back ground levels at 15.2 cm. At present, however, it is not possible to determine whether or not the hydrocarbons are degraded or pose a migration threat

  4. Migration Theories

    Science.gov (United States)

    Crida, Aurélien

    2015-08-01

    The great variety of the architectures of the extra-solar planetary systems has revealed the fundamental role played by planetary migration: the interactions between the planets and the gaseous disk in which they form leads to a modification of their orbits. Here, I will review the basic processes and the most recent results in this area.Planets up to ~50 Earth masses are prone to so-called type I migration.I will describe the processes at play, namely the Lindblad and corotation torques, and explain how the total torque depends on the planet mass and the local disk structure. Application to realistic disks shows one or two sweet spot(s) for outward migration of planets roughly between 5 and 30 Earth masses around the snowline ; this is confirmed by dedicated 3D numerical simulations. This has strong consequences on the formation of hot Super-Earths or mini-Neptunes.For smaller mass planets, it has been recently proposed that the heating of the neighboring gas by the luminous planet can lead to a positive torque, hence promoting outward migration. On the other hand, if the planet is not a heat source, a cold finger appears, whose resulting torque is negative. Applications of these two recent results should be discussed.Giant planets open gaps in the proto-planetary disk, and then are supposedly subject to type II migration, following the viscous accretion of the disk. This standard picture has been questioned recently, as gas appears to drift through the gap. Although the gap opening process is well understood in 2D for a planet on a fixed orbit, recent results on 3D simulations or migrating planets make the picture more accurate.Our ever better understanding of planet-disk interactions is of crucial importance as the statistics on extra solar systems keep growing and the results of these interactions are now imaged.

  5. Dateline Migration.

    Science.gov (United States)

    Tomasi, Lydio E., Ed.

    1995-01-01

    Presents data on international migration and its effects in and between various countries in North America, Europe, and Africa. Discussions include refugee, immigrant, and migrant worker flows; the legal, political, and social problems surrounding immigrants; alien terrorism and law enforcement problems; and migrant effects on education, social…

  6. Direct radiometric dating of hydrocarbon deposits using rhenium-osmium isotopes.

    Science.gov (United States)

    Selby, David; Creaser, Robert A

    2005-05-27

    Rhenium-osmium (Re-Os) data from migrated hydrocarbons establish the timing of petroleum emplacement for the giant oil sand deposits of Alberta, Canada, at 112 +/- 5.3 million years ago. This date does not support models that invoke oil generation and migration for these deposits in the Late Cretaceous. Most Re-Os data from a variety of deposits within the giant hydrocarbon system show similar characteristics, supporting the notion of a single source for these hydrocarbons. The Re-Os data disqualify Cretaceous rocks as the primary hydrocarbon source but suggest an origin from older source rocks. This approach should be applicable to dating oil deposits worldwide. PMID:15919988

  7. Exact solutions in a model of vertical gas migration

    Energy Technology Data Exchange (ETDEWEB)

    Silin, Dmitriy B.; Patzek, Tad W.; Benson, Sally M.

    2006-06-27

    This work is motivated by the growing interest in injectingcarbon dioxide into deep geological formations as a means of avoidingatmospheric emissions of carbon dioxide and consequent global warming.One of the key questions regarding the feasibility of this technology isthe potential rate of leakage out of the primary storage formation. Weseek exact solutions in a model of gas flow driven by a combination ofbuoyancy, viscous and capillary forces. Different combinations of theseforces and characteristic length scales of the processes lead todifferent time scaling and different types of solutions. In the case of athin, tight seal, where the impact of gravity is negligible relative tocapillary and viscous forces, a Ryzhik-type solution implies square-rootof time scaling of plume propagation velocity. In the general case, a gasplume has two stable zones, which can be described by travelling-wavesolutions. The theoretical maximum of the velocity of plume migrationprovides a conservative estimate for the time of vertical migration.Although the top of the plume has low gas saturation, it propagates witha velocity close to the theoretical maximum. The bottom of the plumeflows significantly more slowly at a higher gas saturation. Due to localheterogeneities, the plume can break into parts. Individual plumes alsocan coalesce and from larger plumes. The analytical results are appliedto studying carbon dioxide flow caused by leaks from deep geologicalformations used for CO2 storage. The results are also applicable formodeling flow of natural gas leaking from seasonal gas storage, or formodeling of secondary hydrocarbon migration.

  8. The presence of hydrocarbons in southeast Norway

    DEFF Research Database (Denmark)

    Hanken, Niels Martin; Hansen, Malene Dolberg; Kresten Nielsen, Jesper; Olaussen, Snorre; Buchardt, Bjørn; Eggebø, Tor

    Hydrocarbons, mostly found as solid pyrobitumen, are known from more than 30 localities in southeast Norway. They occur as inclusions in a wide range of "reservoir rocks" spanning from Permo-Carboniferous breccias to veins (vein quartz and calcite veins) in Precambrian granites, gneisses and......, indicating that Alum Shale was the most important source rock. Petrographic investigations combined with stable isotope analyses (d13C and d18O) of the cement containing pyrobitumen indicate two phases of hydrocarbon migration. The first phase probably took place in Upper Silurian to Lower Devonian time......, when the Alum Shale entered the oil window. These hydrocarbons are mostly found as pyrobitumen in primary voids and calcite cemented veins in Cambro-Silurian sedimentary deposits. The second phase is probably of Late Carboniferous/Permian age and was due to the increased heat flow during the formation...

  9. Origin and mobility of hydrocarbon gases in alkaline plutons : the example of the Khibina complex, NW Russia

    Energy Technology Data Exchange (ETDEWEB)

    Treloar, P.J.; Beeskow, B.; Rankin, A.H. [Kingston Univ., Kingston upon Thames (United Kingdom). School of Earth Sciences; Potter, J. [Western Ontario Univ., London, ON (Canada). Dept. of Earth Science; Nivin, V. [Geological Inst., Apatity (Russian Federation). Kola Science Centre

    2006-07-01

    The origin and distribution of abiogenic hydrocarbon gases (HCGs) was discussed with particular reference to HCGs in the Khibina pluton which are dominated by methane (CH{sub 4}) with minor amounts of higher hydrocarbons and hydrogen (H{sub 2}). Although isotopic data and hydrocarbon species ratios point to an abiogenic source, they do not distinguish between primary magmatic hydrocarbons and those generated by late magmatic re-speciation or post-magmatic Fischer-Tropsch (FT) synthesis. Some rock textures suggest limited CH{sub 4} production by FT synthesis, but the presence of primary, syn-magmatic CH{sub 4}-rich fluid inclusions, and the absence of primary and secondary carbon dioxide (CO{sub 2}) rich inclusions, suggest a dominantly early magmatic origin for the HCGs. The permeability and porosity in the Khibina pluton can be constrained by the distribution and geometry of fluid inclusion planes (FIPs) and open cracks (OCs), as well as by the magnitude and pathways of fluid flow. Orientation data for FIPs and OCs, obtained from oriented thin sections, revealed a range of orientations in sub-parallel arrays, suggesting continual re-activation of old fracture systems. The extensive occurrence of OCs and sealed FIPs points to long lived porosities and permeabilities with large fluid fluxes integrated over time. FIP and OC density values were found to be consistent with gas release patterns characterized by spontaneous release during mining of large volumes of HCG stored in a network of interconnected, sealed microfractures and fluid inclusion planes that unzip during stress. It was determined that the HCGs have a primary magmatic origin although there is local evidence for limited post-magmatic FT synthesis. Long term continuous gas migration has occurred within the complex through an interconnected set of fractures. FIPs represent aliquots of gas sealed during open system migration. It was concluded that the complex contains a potentially economically viable methane reservoir.

  10. Evaluation des bassins par modélisation intégrée en deux dimensions des transferts techniques, de l'écoulement des fluides, de la genèse et de la migration des hydrocarbures Basin Evaluation by Integrated Two-Dimensional Modeling of Heat Transfer, Fluid Flow, Hydrocarbon Generation, and Migration

    OpenAIRE

    Chenet P. Y.; Bessis F.; Ungerer P.; Burrus J.; Doligez B.

    2006-01-01

    Le modèle de bassin exposé dans cet article décrit les phénomènes physiques et chimiques qui contrôlent la formation d'accumulations commerciales, dans le cadre évolutif d'un bassin sédimentaire affecté par la subsidence : transfert de chaleur, compaction et écoulement de l'eau, génèse des hydrocarbures, migration diphasique de l'eau et des hydrocarbures. Le modèle tient compte des variations de conductivité et des phénomènes thermiques transitoires pour reconstituer les paléo-températures. D...

  11. Hydrocarbon Reserves: Abundance or Scarcity

    International Nuclear Information System (INIS)

    IFP and the OAPEC jointly organize a regular international seminar dealing with world oil-related problems appearing in the news. For the first time, this seminar has been opened to oil and gas company specialists, service companies, research centers and independents. This year's theme concerns oil and gas reserves: are they abundant or are we headed towards the shortages announced by some experts? This theme is especially topical in that: oil and gas currently meet two thirds of world energy needs and almost completely dominate the transport sector; the reserves declared by the OAPEC countries account for nearly half of world reserves; the price of a barrel of oil went through the roof in 2004; world energy demand is growing fast and alternative sources of energy are far from ready to take over from oil and gas in the next few decades. Since the reserves correspond to the volume it is technically and economically viable to produce, the seminar has, of course, dealt with the technical and economic questions that arise in connection with exploration and production, but it has also considered changes in the geopolitical context. Presentations by the leading companies of the OAPEC countries and by the IFP group were completed by presentation from the International Energy Agency (IEA), the United States Geological Survey (USGS), the IHS Energy Group, Total and Gaz de France. This document gathers the transparencies of the following presentations: Hydrocarbon reserves in OAPEC members countries: current and future (M. Al-Lababidi); Non OAPEC liquid reserves and production forecasts (Y. Mathieu); World oil and gas resources and production outlook (K. Chew); Global investments in the upstream (F. Birol); Total's policy in the oil and gas sector (C. de Margerie); Gaz de France's policy in the oil and gas sector (J. Abiteboul); NOC/IOC's opportunities in OPEC countries (I. Sandrea); Relationships between companies, countries and investors: How they may impact on the growth of reserves and resources (H. Le Leuch); Additional reserves: the role of new technologies - A global perspective on EORIOR (G. Fries); - Updating reservoir models with dynamic data and uncertainty quantification: an integrated approach (F. Roggero); Seismic technology for the OAPEC countries (P. Canal); Exploration knowledge and technologies: impact of progress - Statistical results (N. Alazard); Stratigraphic modelling as a key to find new potentialities in exploration (D. Granjeon); Modelling hydrocarbon migration as a tool for reserve estimation (J-L. Rudkiewicz); The contribution of surface and near surface geology to hydrocarbon discoveries (S.M. Kumati); Contribution of the exploration activity in renewing reserves - The case of Algeria (R. Lounissi); Egypt's petroleum hydrocarbon potential (H. Hataba); Future of hydrocarbon reserves in Syria (T. Hemsh); Natural gas, the fuel of choice for decades to com (M.F. Chabrelie); The role and importance of Arab natural gas in world market (M. Al-Lababidi); LNG and GTL: two pathways for natural gas utilization (C. Cameron); Yet to find hydrocarbon potential (S. Al Menhali); Libyan context of hydrocarbon reserves: abundance or scarcity? (M. Elazi)

  12. Hydrocarbon Reserves: Abundance or Scarcity

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    IFP and the OAPEC jointly organize a regular international seminar dealing with world oil-related problems appearing in the news. For the first time, this seminar has been opened to oil and gas company specialists, service companies, research centers and independents. This year's theme concerns oil and gas reserves: are they abundant or are we headed towards the shortages announced by some experts? This theme is especially topical in that: oil and gas currently meet two thirds of world energy needs and almost completely dominate the transport sector; the reserves declared by the OAPEC countries account for nearly half of world reserves; the price of a barrel of oil went through the roof in 2004; world energy demand is growing fast and alternative sources of energy are far from ready to take over from oil and gas in the next few decades. Since the reserves correspond to the volume it is technically and economically viable to produce, the seminar has, of course, dealt with the technical and economic questions that arise in connection with exploration and production, but it has also considered changes in the geopolitical context. Presentations by the leading companies of the OAPEC countries and by the IFP group were completed by presentation from the International Energy Agency (IEA), the United States Geological Survey (USGS), the IHS Energy Group, Total and Gaz de France. This document gathers the transparencies of the following presentations: Hydrocarbon reserves in OAPEC members countries: current and future (M. Al-Lababidi); Non OAPEC liquid reserves and production forecasts (Y. Mathieu); World oil and gas resources and production outlook (K. Chew); Global investments in the upstream (F. Birol); Total's policy in the oil and gas sector (C. de Margerie); Gaz de France's policy in the oil and gas sector (J. Abiteboul); NOC/IOC's opportunities in OPEC countries (I. Sandrea); Relationships between companies, countries and investors: How they may impact on the growth of reserves and resources (H. Le Leuch); Additional reserves: the role of new technologies - A global perspective on EORIOR (G. Fries); - Updating reservoir models with dynamic data and uncertainty quantification: an integrated approach (F. Roggero); Seismic technology for the OAPEC countries (P. Canal); Exploration knowledge and technologies: impact of progress - Statistical results (N. Alazard); Stratigraphic modelling as a key to find new potentialities in exploration (D. Granjeon); Modelling hydrocarbon migration as a tool for reserve estimation (J-L. Rudkiewicz); The contribution of surface and near surface geology to hydrocarbon discoveries (S.M. Kumati); Contribution of the exploration activity in renewing reserves - The case of Algeria (R. Lounissi); Egypt's petroleum hydrocarbon potential (H. Hataba); Future of hydrocarbon reserves in Syria (T. Hemsh); Natural gas, the fuel of choice for decades to com (M.F. Chabrelie); The role and importance of Arab natural gas in world market (M. Al-Lababidi); LNG and GTL: two pathways for natural gas utilization (C. Cameron); Yet to find hydrocarbon potential (S. Al Menhali); Libyan context of hydrocarbon reserves: abundance or scarcity? (M. Elazi)

  13. Migration of birds

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report covers the migration of birds. Topics covered include why birds migrate, when birds migrate, speed, altitude, courses, distance, major flyways and...

  14. Neuronal Migration Disorders

    Science.gov (United States)

    ... Enhancing Diversity Find People About NINDS NINDS Neuronal Migration Disorders Information Page Table of Contents (click to ... being done? Clinical Trials Organizations What is Neuronal Migration Disorders? Neuronal migration disorders (NMDs) are a group ...

  15. Migration trends in Europe

    OpenAIRE

    Wanner, Philippe ( Laboratoire de démographie et d'études familiales, Université de Genève, Switzerland )

    2002-01-01

    In order to grasp the complexity of migration trends in Europe it is important, given the limitations of the available statistics, to look at the wider issue, breaking it down into four separate elements: 1. the migration flows affecting Council of Europe member states in recent decades, distinguishing between migration between member states and migration flows with other parts of the world; 2. the reasons for migration, with particular reference to illegal migration or asylum; 3. the socio-d...

  16. Hydrocarbon Spectral Database

    Science.gov (United States)

    SRD 115 Hydrocarbon Spectral Database (Web, free access)   All of the rotational spectral lines observed and reported in the open literature for 91 hydrocarbon molecules have been tabulated. The isotopic molecular species, assigned quantum numbers, observed frequency, estimated measurement uncertainty and reference are given for each transition reported.

  17. Gas Migration in the Geosphere: the "Geogas" Theory

    OpenAIRE

    Etiope, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Baciu, C.; Babes-Bolyai University, Cluj-Napoca, Romania

    2007-01-01

    Gas migration in the geosphere is a widespread process, that occurs in numerous geological environments. The most important gases taken into account are CO2, generally present in volcanic and geothermal areas, ans CH4, mainly related to hydrocarbon-prone areas. Diffusion and groundwater flow were traditionally considered as the main mechanisms responsible for the gas migration. However, this approach failed to explain the behaviour of gases in particular situations, such as the long distance ...

  18. Evolution of cuticular hydrocarbons of Hawaiian Drosophilidae.

    Science.gov (United States)

    Alves, Helena; Rouault, Jacques-Deric; Kondoh, Yasuhiro; Nakano, Yoshiro; Yamamoto, Daisuke; Kim, Yong-Kyu; Jallon, Jean-Marc

    2010-09-01

    Hawaiian Drosophila offer an excellent model for adaptive evolution. More than 500 species are reported in Hawaiian islands, and there is considerable diversity in behavior and morphology. Such diversity is mainly driven by sexual selection. In this study qualitative and quantitative chemical compositions of cuticular hydrocarbons (CHCs) in 138 flies belonging to 27 Hawaiian Drosophila species, picture-winged and non picture-winged, were analyzed regarding sexual dimorphism, differences in saturation, branching position, and lengths of CHCs. We found significant variation in the CHC patterns. In several subgroups, new species show decreases in unsaturated hydrocarbons, and gradual increases in branched compounds, monomethylalkanes and dimethylalkanes, not commonly found in Drosophila. Moreover, branching positions gradually shifted towards internal carbons, and chain lengths increased in the new species. The long-term evolution of CHCs in the light of the recent evolutionary migration and adaptation history of Hawaiian Drosophila species along the developing archipelago was discussed. PMID:20480222

  19. Secondary parkinsonism

    Science.gov (United States)

    Parkinsonism - secondary; Atypical Parkinson disease ... to be less responsive to medical therapy than Parkinson disease. ... Unlike Parkinson disease, some types of secondary parkinsonism may stabilize or even improve if the underlying cause is treated. ...

  20. Higher carotinoid petroleum hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Vorob`yeva, N.S.; Zemskova, Z.K.; Punanov, V.G.; Petrov, A.A. [Institute of Geology and Development of Fossil Fuels, Moscow (Russian Federation)

    1993-12-31

    Gas chromatography and chromato-mass spectrometry have been used to investigate the saturated hydrocarbon fraction of crude oil from the Sary-Bulak field (Zaisansk basin, Kazakhstan). The high concentration of higher carotinoid cyclanes in the mixture investigated is shown: lexane (C{sub 33}), {gamma}- and {beta}-carotanes (C{sub 40}). The content of the latter hydrocarbon in the saturated fraction reaches 2{center_dot}5%. Ways in which these cyclanes are formed from natural carotinoids are discussed. Mass spectra of the hydrocarbons identified are presented. 8 refs., 4 figs.

  1. Isoprenoid petroleum hydrocarbons

    Science.gov (United States)

    Petrov, Al A.; Abryutina, N. N.

    1989-06-01

    The outcome of studies on the chemistry of petroleum carried out during the last 10-15 years is examined. It is shown that petroleum is a very complex mixture of natural products, the most important place among which is occupied by C10-C40 isoprenoid hydrocarbons represented by aliphatic, alicyclic, and aromatic compounds. The relations between the isoprenoid petroleum hydrocarbons and their possible bioorganic precursors are discussed. The possibility of using isoprenoid hydrocarbons (as biomarkers) in discovering the pathways leading to the genesis and chemical evolution of petroleums and also prospecting for petroleum deposits is demonstrated. The bibliography includes 104 references.

  2. Chemical contamination and transformation of soils in hydrocarbon production regions

    Science.gov (United States)

    Zamotaev, I. V.; Ivanov, I. V.; Mikheev, P. V.; Nikonova, A. N.

    2015-12-01

    The current concepts of soil pollution and transformation in the regions of hydrocarbon production have been reviewed. The development of an oil field creates extreme conditions for pedogenesis. Tendencies in the radial migration, spatial distribution, metabolism, and accumulation of pollutants (oil, oil products, and attendant heavy metals) in soils of different bioclimatic zones have been analyzed. The radial and lateral mobility of pollution halos is a universal tendency in the technogenic transformation of soils and soil cover in the regions of hydrocarbon production. The biodegradation time of different hydrocarbon compounds strongly varies under different landscape conditions, from several months to several tens of years. The transformation of original (mineral and organic) soils to their technogenic modifications (mechanically disturbed, chemically contaminated, and chemo soils and chemozems) occurs in the impact zone of technogenic hydrocarbon fluxes under any physiographical conditions. The integrated use of the existing methods for the determination of the total content and qualitative composition of bituminous substances and polyaromatic hydrocarbons in combination with the chromatographic determination of normal alkanes and hydrocarbon gases, as well as innovative methods of studies, allows revealing new processes and genetic relationships in soils and studying the functioning of soils and soil cover. The study of the hydrocarbon contamination of soils is important for development of restoration measures and lays the groundwork for the ecological and hygienic regulation based on the zonation of soil and landscape resistance to different pollutants.

  3. International Migration and Remittances

    OpenAIRE

    Dattatray Sitaram Bagade

    2012-01-01

    Human migration is a physical movement by human beings from one geographical areato another geographical area. Migration is internal as well as external. At theinternational level, no universally accepted definition for “Migrant” exists. The UniteNations defines “migration as an individual who has resided in a foreign country formore than one year irrespective of the causes, voluntary or involuntary, and the means,regular or irregular, used migrate”. Key terms of migrations is documented migr...

  4. Immunoassay for petroleum hydrocarbons

    International Nuclear Information System (INIS)

    Petroleum hydrocarbon contamination of soil and ground water has become a serious environmental problem. Since the 1940s, it has been a common practice to bury fuel tanks underground to guard against fire and explosions. The leakage of petroleum fuel from these aging tanks creates a long term threat to human health. In order to location and identify these sources of contamination, an on-site screening test is very desirable. A simple, inexpensive petroleum hydrocarbon immunoassay has been developed for this purpose. The EnviroGard Petroleum Hydrocarbon test kit is designed for qualitative or semiquantitative analysis of petroleum hydrocarbon fuel in soil and ground water. The assay can be easily used on-site and takes 15 minutes to perform. Following a 2 minute methanol extraction, the test is performed in polystyrene tubes and can detect gasoline, diesel fuel, kerosene, home heating oil and other major fuels at ppm levels in soil and sub-ppm levels in water samples

  5. Hydrocarbon geoscience research strategy

    Energy Technology Data Exchange (ETDEWEB)

    1990-04-01

    This document outlines a strategy for oil and gas related research focused on optimizing the economic producibility of the Nation's resources. The Hydrocarbon Geoscience Strategy was developed by the Hydrocarbon Geoscience Research Coordinating Committee of the Department of Energy (DOE). This strategy forms the basis for the development of DOE Fossil Energy's Oil Research Program Implementation Plan and Natural Gas Program Implementation Plan. 24 refs., 5 figs., 3 tabs.

  6. Enterohepatic Migration of Fish Bone Resulting in Liver Abscess.

    Science.gov (United States)

    Ede, Chikwendu; Sobnach, Sanju; Kahn, Delawir; Bhyat, Ahmed

    2015-01-01

    Liver abscess formation due to enterohepatic migration of a foreign body is extremely rare. Foreign body ingestion is generally an unconscious and painless event, thus complicating preoperative diagnosis in most patients. We report the case of a 61-year-old man who presented with secondary peritonitis from a ruptured hepatic abscess after an ingested fish bone migrated into the liver. PMID:26634168

  7. Minneapolis Multi-Ethnic Curriculum Project--Migration Unit.

    Science.gov (United States)

    Minneapolis Public Schools, Minn. Dept. of Intergroup Education.

    The student booklet presents short chapters illustrating the migration unit of the Minneapolis Multi-Ethnic Curriculum Project for secondary schools. Sixteen brief chapters describe migration, immigration, and emigration in the United States. The first six chapters offer first person accounts of immigrants from Norway, Korea, Egypt, Hitler's…

  8. Hydrocarbons (aliphatic and aromatic) in the snow-ice cover in the Arctic

    International Nuclear Information System (INIS)

    This paper presented the concentration and composition of aliphatic hydrocarbons and polycyclic aromatic hydrocarbons (PAHs) in snow and ice-infested waters in the France-Victoria trough in the northern Barents Sea and in the Mendeleev ridge in the Amerasian basin of the Arctic Ocean. Extreme conditions such as low temperatures, ice sheets and the polar nights render the arctic environment susceptible to oil spills. Hydrocarbons found in these northern seas experience significant transformations. In order to determine the sources, pathways and transformations of the pollutants, it is necessary to know their origin. Hydrocarbon distributions is determined mostly by natural hydrobiological and geochemical conditions. The regularity of migration is determined by natural factors such as formation and circulation of air and ice drift. There is evidence suggesting that the hydrocarbons come from pyrogenic sources. It was noted that hydrocarbons could be degraded even at low temperatures. 17 refs., 1 tab

  9. NNDC database migration project

    International Nuclear Information System (INIS)

    NNDC Database Migration was necessary to replace obsolete hardware and software, to be compatible with the industry standard in relational databases (mature software, large base of supporting software for administration and dissemination and replication and synchronization tools) and to improve the user access in terms of interface and speed. The Relational Database Management System (RDBMS) consists of a Sybase Adaptive Server Enterprise (ASE), which is relatively easy to move between different RDB systems (e.g., MySQL, MS SQL-Server, or MS Access), the Structured Query Language (SQL) and administrative tools written in Java. Linux or UNIX platforms can be used. The existing ENSDF datasets are often VERY large and will need to be reworked and both the CRP (adopted) and CRP (Budapest) datasets give elemental cross sections (not relative I?) in the RI field (so it is not immediately obvious which of the old values has been changed). But primary and secondary intensities are now available on the same scale. The intensity normalization has been done for us. We will gain access to a large volume of data from Budapest and some of those gamma-ray intensity and energy data will be superior to what we already have

  10. Migration and revolution

    Directory of Open Access Journals (Sweden)

    Nando Sigona

    2012-06-01

    Full Text Available The Arab Spring has not radically transformed migration patterns in the Mediterranean, and the label ‘migration crisis’ does not do justice to the composite and stratified reality.

  11. MIGRATION IN SIKKIM: FACTS OR FRICTIONS

    Directory of Open Access Journals (Sweden)

    Gyaltsen Tsh. Bhutia

    2014-04-01

    Full Text Available Today's migrations become one of the important issues in the globe. The increasing influx of migration and the illegal migration has become a great challenge to the policy maker for both the sending and destination economy. The impact of migration on both the economy has genuine issue to be discusses, analysis and closely study. Therefore, this study reveal to quantify the migration population in Sikkim, to assess the impact on the socio-economy fabrics and to suggest the remedies had to cope up the situation amicably. This study is purely based on secondary data which is collected from Census 1991, Census 2001, Census 2011, A Statistical Profile of Sikkim 2002, State Socio-Economy Census 2006 etc. Migration has positive as well as negative impact on both the economy. Sikkim is a small state touches international boundary with least population and peace loving state. But after merge with the Indian Union the influx of migration is recorded high. Therefore, an attempt has been made to highlight the demographic pattern of Sikkim, economic activities of the migrants and their impact on Sikkim economy

  12. Population, migration and urbanization.

    Science.gov (United States)

    1982-06-01

    Despite recent estimates that natural increase is becoming a more important component of urban growth than rural urban transfer (excess of inmigrants over outmigrants), the share of migration in the total population growth has been consistently increasing in both developed and developing countries. From a demographic perspective, the migration process involves 3 elements: an area of origin which the mover leaves and where he or she is considered an outmigrant; the destination or place of inmigration; and the period over which migration is measured. The 2 basic types of migration are internal and international. Internal migration consists of rural to urban migration, urban to urban migration, rural to rural migration, and urban to rural migration. Among these 4 types of migration various patterns or processes are followed. Migration may be direct when the migrant moves directly from the village to the city and stays there permanently. It can be circular migration, meaning that the migrant moves to the city when it is not planting season and returns to the village when he is needed on the farm. In stage migration the migrant makes a series of moves, each to a city closer to the largest or fastest growing city. Temporary migration may be 1 time or cyclical. The most dominant pattern of internal migration is rural urban. The contribution of migration to urbanization is evident. For example, the rapid urbanization and increase in urban growth from 1960-70 in the Republic of Korea can be attributed to net migration. In Asia the largest component of the population movement consists of individuals and groups moving from 1 rural location to another. Recently, because urban centers could no longer absorb the growing number of migrants from other places, there has been increased interest in the urban to rural population redistribution. This reverse migration also has come about due to slower rates of employment growth in the urban centers and improved economic opportunities in rural areas. According to UN data, at the global level the trend in longterm and permanent migration is towards stabilization or decline in the rate of movement into developed countries like the US, Canada, the UK, and Australia from developing countries. Migrants in the Asian and Pacific region mostly tend to be in the 15-25 year age group. Most migrants streams are male dominant. The rural urban migration stream includes a large proportion of people who are better educated than their rural counterparts but generally less educated than the urban natives. Reasons for migrating in the Asian and Pacific region are economic, educational, sociocultural and political. A negative factor in rural migration is that it deprives villages of the ablest people. PMID:12265662

  13. Irregular Migration of Egyptians

    OpenAIRE

    ROMAN, Howaida

    2008-01-01

    After defining irregular migration and tackling its different dimensions, the analytical note proposes to analyse the causes and dynamics of irregular migration in Egypt. It highlights furthermore the determinants of EU Policies in the realm of irregular migration, and Egypt’s policy-making approach towards irregular migrants. The conclusion emphasizes the necessity of forging coherent and effective policies on irregular migration in the context of a partnership between origin countries and d...

  14. Globalization, Migration and Development

    OpenAIRE

    George, Susan; Samuel, John

    2002-01-01

    EnglishMigration may become the most important branch of demography in the earlydecades of the new millennium in a rapidly globalizing world. This paper discusses the causes, costsand benefits of international migration to countries of the South and North, and key issues of commonconcern. International migration is as old as national boundaries, though its nature, volume,direction, causes and consequences have changed. The causes of migration are rooted in the rate ofpopulation growth and the...

  15. Marriage, money and migration

    OpenAIRE

    Åström, Johanna

    2009-01-01

    The thesis consists of a summary and four self-contained papers. Paper [I] examines the effects of interregional migration on gross earnings in married and cohabiting couples. In particular, we examine the link between education level and income gains. We find that pre-migration education level is a key determinant of migration and economic outcomes and is also a determinant of the effect of migration on income distribution within the household. The positive average effect on household earnin...

  16. Heuristical Strategies on the Study Theme "The Unsaturated Hydrocarbons -- Alkenes"

    Science.gov (United States)

    Naumescu, Adrienne Kozan; Pasca, Roxana-Diana

    2011-01-01

    The influence of heuristical strategies upon the level of two experimental classes is studied in this paper. The didactic experiment took place at secondary school in Cluj-Napoca, in 2008-2009 school year. The study theme "The Unsaturated Hydrocarbons--Alkenes" has been efficiently learned by using the most active methods: laboratory…

  17. Sulfidization and magnetization above hydrocarbon reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, R.L.; Goldhaber, M.B.; Tuttle, M.L. (U.S. Geological Survey, Denver, CO (United States))

    1991-03-01

    Geochemical and rock magnetic studies of strata over Cement oil field (Anadarko basin, Oklahoma), Simpson oil field (North Slope basin, Alaska), and the Edwards deep gas trend, south Texas coastal plain, document changes in original magnetizations caused by postdepositional iron sulfide minerals that are, or may be, related to hydrocarbon seepage. At Cement, ferrimagnetic pyrrhotite (Fe{sub 7}S{sub 8}) formed with pyrite and marcasite in Permian red beds. The Fe-S minerals contain isotopically heavy, abiogenic sulfur derived from thermal degradation of petroleum and (or) isotopically light sulfur derived from sulfate-reducing bacteria fed by leaking hydrocarbons. At Simpson, ferrimagnetic greigite (Fe{sub 3}S{sub 4}) dominates magnetizations in Upper Cretaceous nonmarine beds that contain biodegraded oil. Sulfur isotopic data are consistent with, but do not prove, a genetic link between the greigite ({delta}{sup 34}S {gt} +20 per mil) and seepage. In middle Tertiary sandstones of southeast Texas, pyrite and marcasite formed when abiogenic H{sub 2}S migrated upward from deep reservoirs, or when H{sub 2}S was produced at shallow depths by bacteria that utilized organic material dissolved in migrating water from depth. The sulfide minerals replaced detrital magnetite to result in a systematic decrease in magnetic susceptibility toward faults that connect deep petroleum reservoirs to shallow sandstone. The authors results show that abiologic and biologic mechanisms can generate magnetic sulfide minerals in some sulfidic zones of hydrocarbon seepage. The magnetizations in such zones are diminished most commonly by replacement of detrital magnetic minerals with nonmagnetic sulfide minerals or are unchanged if such detrital minerals were originally absent.

  18. Migration and Adult Education

    Science.gov (United States)

    Gois, William

    2007-01-01

    The objective of this paper is to highlight the role of adult education as a tool in addressing labour migration issues, specifically those concerning the protection of migrant workers' rights and the transformation of the impact of migration into positive holistic developmental gains. The view of labour migration as a means to forge the economic…

  19. More Myths of Migration.

    Science.gov (United States)

    Basch, Linda; Lerner, Gail

    1986-01-01

    Challenges "myths" about women and migration, including (1) the causes of migration are economic, not racism; (2) migrant women receive support from feminist groups and trade unions; (3) transnational corporations are positive forces in developing nations; (4) migration today has little impact on family life; and (5) most migrants cluster in…

  20. Superconductivity in aromatic hydrocarbons

    International Nuclear Information System (INIS)

    Highlights: • Aromatic superconductor is one of core research subjects in superconductivity. Superconductivity is observed in certain metal-doped aromatic hydrocarbons. Some serious problems to be solved exist for future advancement of the research. This article shows the present status of aromatic superconductors. - Abstract: ‘Aromatic hydrocarbon’ implies an organic molecule that satisfies the (4n + 2) π-electron rule and consists of benzene rings. Doping solid aromatic hydrocarbons with metals provides the superconductivity. The first discovery of such superconductivity was made for K-doped picene (Kxpicene, five benzene rings). Its superconducting transition temperatures (Tc’s) were 7 and 18 K. Recently, we found a new superconducting Kxpicene phase with a Tc as high as 14 K, so we now know that Kxpicene possesses multiple superconducting phases. Besides Kxpicene, we discovered new superconductors such as Rbxpicene and Caxpicene. A most serious problem is that the shielding fraction is ⩽15% for Kxpicene and Rbxpicene, and it is often ∼1% for other superconductors. Such low shielding fractions have made it difficult to determine the crystal structures of superconducting phases. Nevertheless, many research groups have expended a great deal of effort to make high quality hydrocarbon superconductors in the five years since the discovery of hydrocarbon superconductivity. At the present stage, superconductivity is observed in certain metal-doped aromatic hydrocarbons (picene, phenanthrene and dibenzopentacene), but the shielding fraction remains stubbornly low. The highest priority research area is to prepare aromatic superconductors with a high superconducting volume-fraction. Despite these difficulties, aromatic superconductivity is still a core research target and presents interesting and potentially breakthrough challenges, such as the positive pressure dependence of Tc that is clearly observed in some phases of aromatic hydrocarbon superconductors, suggesting behavior not explained by the standard BCS picture of superconductivity. In this article, we describe the present status of this research field, and discuss its future prospects

  1. Geochemical assessment of light gaseous hydrocarbons in near-surface soils of Kutch–Saurashtra: Implication for hydrocarbon prospects

    Indian Academy of Sciences (India)

    P Lakshmi Srinivasa Rao; T Madhavi; D Srinu; M S Kalpana; D J Patil; A M Dayal

    2013-02-01

    Light hydrocarbons in soil have been used as direct indicators in geochemical hydrocarbon exploration, which remains an unconventional path in the petroleum industry. The occurrence of adsorbed soil gases, methane and heavier homologues were recorded in the near-surface soil samples collected from Kutch–Saurashtra, India. Soil gas alkanes were interpreted to be derived from deep-seated hydrocarbon sources and have migrated to the surface through structural discontinuities. The source of hydrocarbons is assessed to be thermogenic and could have been primarily derived from humic organic matter with partial contribution from sapropelic matter. Gas chromatographic analyses of hydrocarbons desorbed from soil samples through acid extraction technique showed the presence of methane through -butane and the observed concentrations (in ppb) vary from: methane (C1) from 4–291, ethane (C2) from 0–84, propane (C3) from 0–37, i-butane (iC4) from 0–5 and -butane (nC4) from 0–4. Carbon isotopes measured for methane and ethane by GC-C-IRMS, range between ?42.9‰ to ?13.3‰ (Pee Dee Belemnite – PDB) and ?21.2‰ to ?12.4‰ (PDB), respectively. The increased occurrence of hydrocarbons in the areas near Anjar of Kutch and the area south to Rajkot of Saurashtra signifies the area potential for oil and gas.

  2. Geochemical assessment of light gaseous hydrocarbons in near-surface soils of Kutch-Saurashtra: Implication for hydrocarbon prospects

    Science.gov (United States)

    Rao, P. Lakshmi Srinivasa; Madhavi, T.; Srinu, D.; Kalpana, M. S.; Patil, D. J.; Dayal, A. M.

    2013-02-01

    Light hydrocarbons in soil have been used as direct indicators in geochemical hydrocarbon exploration, which remains an unconventional path in the petroleum industry. The occurrence of adsorbed soil gases, methane and heavier homologues were recorded in the near-surface soil samples collected from Kutch-Saurashtra, India. Soil gas alkanes were interpreted to be derived from deep-seated hydrocarbon sources and have migrated to the surface through structural discontinuities. The source of hydrocarbons is assessed to be thermogenic and could have been primarily derived from humic organic matter with partial contribution from sapropelic matter. Gas chromatographic analyses of hydrocarbons desorbed from soil samples through acid extraction technique showed the presence of methane through n-butane and the observed concentrations (in ppb) vary from: methane (C1) from 4-291, ethane (C2) from 0-84, propane (C3) from 0-37, i-butane (iC4) from 0-5 and n-butane (nC4) from 0-4. Carbon isotopes measured for methane and ethane by GC-C-IRMS, range between -42.9‰ to -13.3‰ (Pee Dee Belemnite - PDB) and -21.2‰ to -12.4‰ (PDB), respectively. The increased occurrence of hydrocarbons in the areas near Anjar of Kutch and the area south to Rajkot of Saurashtra signifies the area potential for oil and gas.

  3. HYDROCARBONS DIAGNOSTIC OF POLLUTED SOILS

    Directory of Open Access Journals (Sweden)

    Mohamed Arad

    2010-12-01

    Full Text Available Petroleum hydrocarbons are known as carcinogenic and may contaminate the environment (water, air and soil. In this study, a diagnostic of polluted soils by petroleum hydrocarbons is carried out in order to know the effect of their accumulation as well as their behavior in time. The aging factor, a source of significant changing in hydrocarbon behavior, is integrated on two sites of an industrial refinery as experimental samples. The first site is recently polluted by hydrocarbons while the second is a previously polluted site.The results indicate that the concentration of hydrocarbons on the surface of the first site is greater and remains stable in time, as for the second site, hydrocarbons concentration on the surface is also important and undergoes a weak reduction. At a depth of one meter hydrocarbons exist at a greater concentration. This shows that obstinate hydrocarbons are an environmental danger for fauna and flora.

  4. Process for hydroforming hydrocarbon liquids

    International Nuclear Information System (INIS)

    This patent describes a process for hydroforming hydrocarbon liquids contacting the hydrocarbon liquids with water and hydrogen in the presence of a mixed- solid solution tri-metallic oxide/sulfide catalyst having the formula: MIOaSbMIIOcMIIIOd

  5. Defining the phenotype of neutrophils following reverse migration in zebrafish.

    Science.gov (United States)

    Ellett, Felix; Elks, Philip M; Robertson, Anne L; Ogryzko, Nikolay V; Renshaw, Stephen A

    2015-12-01

    Stimulation of neutrophil reverse migration presents an attractive, alternative therapeutic pathway to driving inflammation resolution. However, little is known about whether the activity of wound-experienced neutrophils is altered and whether encouraging dispersal of such neutrophils back into the body may have undesirable consequences. This study used a zebrafish tail transection inflammation model, in combination with a photoconvertible neutrophil transgenic line, to allow internally controlled, simultaneous comparison of reverse-migrated neutrophils with naïve neutrophils in the presence and absence of secondary insult. Detailed microscopy revealed that reverse-migrated neutrophils exhibited an activated morphology but responded normally to secondary insult and are able to mount an effective antimicrobial response to Staphylococcus aureus. These results support a model in which reverse-migrated neutrophils exhibit no long-term behavioral alterations and encourage the notion of enhanced reverse migration as a viable target for pharmaceutical manipulation. PMID:26071567

  6. Electrokinetic studies of dispersed systems of solid hydrocarbons from crude oil

    Energy Technology Data Exchange (ETDEWEB)

    Agaev, S.G.; Gundyrev, A.A.; Kazakova, L.P.

    1971-01-01

    Electrokinetic phenomena in nonaqueous dispersed systems of solid hydrocarbons are related to deparaffinization and oil-stripping processes. Authors studied the effect of direct current on suspensions of solid hydrocarbons in organic solvents. Aromatic and aliphatic solvents, ketones, and chlorinated liquids were used. About 1 g of solid hydrocarbon was suspended in 10 ml of solvent, and exposed to a voltage of 12.5 kv/cm. In some cases, the hydrocarbon migrated to the cathode; in other cases, migration toward both cathode and anode occurred. Thus the direct electric current produced electrophoresis, double electrophoresis, and interelectrode circulation, accompanied by aggregation of dispersed phase particles and various characteristics of structure formation. All these phenomena are related to formation of the double electric layer at the phase boundaries.

  7. Theoretical base of new technology of hydrocarbons exploration in the south Caspian basin

    International Nuclear Information System (INIS)

    Full text : This article provides with new data, which are of great importance for the understanding of hydrocarbon system peculiarities if the south Caspian basin. There was determined non-coincidence and sometimes back correlation in the folded structure of complexes of different ages and also different orientation of axes of the folds and directions of faults in different tectonic zones. In the sedimentary cover of the south Caspian basin there were identified specific structures associated with generation and migration of hydrocarbons. Large-scale migration of hydrocarbons occurs instantly from time to time. It was determined that most earthquakes occurs in the south Caspian basin in the sedimentary cover at depth from 10 to 20 km and paragenesis of mud volcanos eruptions was determined too. There exist an opinion that the improved technology of hydrocarbon exploration will increase the efficiency of exploration works in a complex basin like the south Caspian one.

  8. Organic geochemistry of the Vindhyan sediments: Implications for hydrocarbons

    Science.gov (United States)

    Dayal, A. M.; Mani, Devleena; Madhavi, T.; Kavitha, S.; Kalpana, M. S.; Patil, D. J.; Sharma, Mukund

    2014-09-01

    The organic geochemical methods of hydrocarbon prospecting involve the characterization of sedimentary organic matter in terms of its abundance, source and thermal maturity, which are essential prerequisites for a hydrocarbon source rock. In the present study, evaluation of organic matter in the outcrop shale samples from the Semri and Kaimur Groups of Vindhyan basin was carried out using Rock Eval pyrolysis. Also, the adsorbed low molecular weight hydrocarbons, methane, ethane, propane and butane, were investigated in the near surface soils to infer the generation of hydrocarbons in the Vindhyan basin. The Total Organic Carbon (TOC) content in shales ranges between 0.04% and 1.43%. The S1 (thermally liberated free hydrocarbons) values range between 0.01-0.09 mgHC/gRock (milligram hydrocarbon per gram of rock sample), whereas the S2 (hydrocarbons from cracking of kerogen) show the values between 0.01 and 0.14 mgHC/gRock. Based on the Tmax (temperature at highest yield of S2) and the hydrogen index (HI) correlations, the organic matter is characterized by Type III kerogen. The adsorbed soil gas, CH4 (C1), C2H6 (C2), C3H8 (C3) and nC4H10, (nC4), concentrations measured in the soil samples from the eastern part of Vindhyan basin (Son Valley) vary from 0 to 186 ppb, 0 to 4 ppb, 0 to 5 ppb, and 0 to 1 ppb, respectively. The stable carbon isotope values for the desorbed methane (?13C1) and ethane (?13C2) range between -45.7‰ to -25.2‰ and -35.3‰ to -20.19‰ (VPDB), respectively suggesting a thermogenic source for these hydrocarbons. High concentrations of thermogenic hydrocarbons are characteristic of areas around Sagar, Narsinghpur, Katni and Satna in the Son Valley. The light hydrocarbon concentrations (C1-C4) in near surface soils of the western Vindhyan basin around Chambal Valley have been reported to vary between 1-2547 ppb, 1-558 ppb, 1-181 ppb, 1-37 ppb and 1-32 ppb, respectively with high concentrations around Baran-Jhalawar-Bhanpur-Garot regions (Kumar et al., 2006). The light gaseous hydrocarbon anomalies are coincident with the wrench faults (Kota - Dholpur, Ratlam - Shivpuri, Kannod - Damoh, Son Banspur - Rewa wrench) in the Vindhyan basin, which may provide conducive pathways for the migration of the hydrocarbons towards the near surface soils.

  9. Optrode for sensing hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Miller, H.; Milanovich, F.P.; Hirschfeld, T.B.; Miller, F.S.

    1987-05-19

    A two-phase system employing the Fujiwara reaction is provided for the fluorometric detection of halogenated hydrocarbons. A fiber optic is utilized to illuminate a column of pyridine trapped in a capillary tube coaxially attached at one end to the illuminating end of the fiber optic. A strongly alkaline condition necessary for the reaction is maintained by providing a reservoir of alkali in contact with the column of pyridine, the surface of contact being adjacent to the illuminating end of the fiber optic. A semipermeable membrane caps the other end of the capillary tube, the membrane being preferentially permeable to the halogenated hydrocarbon but preferentially impermeable to water and pyridine. As the halogenated hydrocarbon diffuses through the membrane and into the column of pyridine, fluorescent reaction products are formed. Light propagated by the fiber optic from a light source, excites the fluorescent products. Light from the fluorescence emission is also collected by the same fiber optic and transmitted to a detector. The intensity of the fluorescence gives a measure of the concentration of the halogenated hydrocarbons. 6 figs.

  10. Optrode for sensing hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Miller, H.; Milanovich, F.P.; Hirschfeld, T.B.; Miller, F.S.

    1988-09-13

    A two-phase system employing the Fujiwara reaction is provided for the fluorometric detection of halogenated hydrocarbons. A fiber optic is utilized to illuminate a column of pyridine trapped in a capillary tube coaxially attached at one end to the illuminating end of the fiber optic. A strongly alkaline condition necessary for the reaction is maintained by providing a reservoir of alkali in contact with the column of pyridine, the surface of contact being adjacent to the illuminating end of the fiber optic. A semipermeable membrane caps the other end of the capillary tube, the membrane being preferentially permeable to the halogenated hydrocarbon and but preferentially impermeable to water and pyridine. As the halogenated hydrocarbon diffuses through the membrane and into the column of pyridine, fluorescent reaction products are formed. Light propagated by the fiber optic from a light source, excites the fluorescent products. Light from the fluorescence emission is also collected by the same fiber optic and transmitted to a detector. The intensity of the fluorescence gives a measure of the concentration of the halogenated hydrocarbons. 5 figs.

  11. Optrode for sensing hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Holly (Bethel Island, CA); Milanovich, Fred P. (Lafayette, CA); Hirschfeld, Tomas B. (Livermore, CA); Miller, Fred S. (Bethel Island, CA)

    1988-01-01

    A two-phase system employing the Fujiwara reaction is provided for the fluorometric detection of halogenated hydrocarbons. A fiber optic is utilized to illuminate a column of pyridine trapped in a capillary tube coaxially attached at one end to the illuminating end of the fiber optic. A strongly alkaline condition necessary for the reaction is maintained by providing a reservoir of alkali in contact with the column of pyridine, the surface of contact being adjacent to the illuminating end of the fiber optic. A semipermeable membrane caps the other end of the capillary tube, the membrane being preferentially permeable to the halogenated hydrocarbon and but preferentially impermeable to water and pyridine. As the halogenated hydrocarbon diffuses through the membrane and into the column of pyridine, fluorescent reaction products are formed. Light propagated by the fiber optic from a light source, excites the fluorescent products. Light from the fluorescence emission is also collected by the same fiber optic and transmitted to a detector. The intensity of the fluorescence gives a measure of the concentration of the halogenated hydrocarbons.

  12. Hydrocarbon resources in Quebec

    International Nuclear Information System (INIS)

    A leading expert in exploration geology was asked his opinion regarding government intervention in hydrocarbon exploration and development with respect to sustainable development requirements. Fifty-one per cent of Quebec's energy consumption is attributed to hydrocarbons and 38 per cent to electricity. It is expected that proportions of this demand will remain the same for several decades. This paper evaluates Quebec's hydrocarbon potential and exploration to meet future energy demands. It was suggested that the Quebec government should explore the idea of uniting government, university and private enterprises in assessing the resource potential of Quebec's sedimentary basins with the possibility of using strategic information from oil and gas companies to improve existing databases. Quebec's objective is to improve energy security and supply and to improve the economic prosperity of Quebec's natural resource development, particularly hydrocarbons. It was also emphasized that oil and gas exploration should eventually be harmonized with renewable energy source development, a transition that could take several decades. 2 tabs., 2 figs

  13. Environmental degradation of petroleum hydrocarbons

    OpenAIRE

    Heul, R.M. van der

    2011-01-01

    Petroleum hydrocarbons are causing widespread pollution in both the aquatic and the terrestrial environment. Petroleum consist of alkanes, cycloalkanes, aromatics, polyaromatics (PAHs) and other compounds. All of these hydrocarbons groups are toxic for the environment, but especially the PAHs and their degradation products are known for their carcinogenic properties. The partitioning of hydrocarbons in the environments depends on volatility and hydrophobicity, influencing the partitioning...

  14. Ejected Sedimentary Rocks of Mud Volcanoes as Indicators of Depositional Environments and of Hydrocarbon Generation within the South Caspian Basin, Azerbaijan

    Science.gov (United States)

    Berner, U.; Scheeder, G.; Kus, J.; Köthe, A.; Movsumova, U.

    2009-04-01

    Mud volcanoes are prominent geological features of the South Caspian Basin of Azerbaijan, one of the oldest oil producing regions worldwide. The basin is characterized by extreme sedimentation rates, which lead to the accumulation of large volumes of Mesozoic and Cenozoic sediments. These mostly unconsolidated strata reach thicknesses of up to 20 km and overlay a continental basement in the onshore part. Tectonic forces control the occurrences of mud volcanoes in regions with over-pressured subsurface sediments as mud volcanoes are closely linked to fault systems. The mud volcanoes of Azerbaijan are a surface expression of vertical hydrocarbon migration and offer the chance to investigate the subsurface by means of ejected rocks transported to the surface. These rocks of Mesozoic and Cenozoic sedimentary sequences are potential indicators of the regional hydrocarbon generation. The mud of nineteen volcano cones contained numerous ejected rock fragments, which we use to identify environmental and depositional parameters of the sediments of the Caspian Basin. We also intended to estimate the depth range from which the mud was transported to the surface using organic geochemical parameters. Mircopalaeontological investigations (calcareous nannoplankton) have been performed on selected samples. These analyses suggest that the investigated sediments are of Late Cretaceous to Palaeogene ages and relate to the stratigraphic interval during which the main hydrocarbon source rocks of Azerbaijan have been deposited. Organic geochemical, organic petrographical and mircopalaeontological investigations have been performed on selected samples of nineteen mud volcanoes. Analyses total organic carbon and total sulphur were performed on an elemental analyzer. These analyses suggest that the sediments can be classified as anoxic marine deposits whereas only few are sediments of a lacustrine environment. Bulk source rock information were obtained from RockEval pyrolysis. Resulting Hydrogen and oxygen indices indicate that the organic matter of the sediments consist mostly of mixtures of aquatic and terrestrial organic matter. The hydrocarbons of the sediments were extracted and subsequently fractionated into aliphatic, aromatic and hetero-compound groups. The amounts of extractable hydrocarbons in relation to organic carbon contents indicate that most of the ejected sedimentary rocks contain migrated hydrocarbons. All extracted hydrocarbons have been affected by secondary alterations which most likely involved biodegradation the chromatographic analyses of the aliphatic fraction indicate elevated ratios of pristane/n-C17 and phytane/n-C18 and the chromatograms generally show that the normal alkanes have been removed to a large extend. Despite of biodegardation, environmental and maturity indicative biomarkers could be identified, and C27- to C29-sterane isomers suggest a dominant imprint of aquatic organic matter on the extracted hydrocarbons. An influence of diatoms on the sterane distribution seems plausible, but an admixture of land plant material is highly likely. Homohopane isomerization ratios as well as the ratio of trisnorneohopane over trisnorhopane suggest that the extracted hydrocarbons come from a coalification range which spreads from immature to mature although, maximum maturity does not reach the peak of oil generation. C29-sterane isomerisation ratios support this finding. Vitrinite reflectance measurements on the ejected rocks indicate a similar range of maturities as suggested from biomarker analyses. However, the data indicate again that most of the investigated rocks have been impregnated by allochthonous hydrocarbons as biomarker maturities may slightly depart from the measured reflectance values. We estimated from maturity/depth conversion that the mud volcanoes along a SSW-NNE transect from the Kura Basin to the Apsheron Peninsula produce their mud from a depth range between 4000 and 5500 m corresponding to a maturity range of 0.5 to 0.65% vitrinite reflectance, although, no specific regional maturity/depth trend cou

  15. Hydrocarbonization research: completion report

    Energy Technology Data Exchange (ETDEWEB)

    Youngblood, E.L.; Cochran, H.D. Jr.; Westmoreland, P.R.; Brown, C.H. Jr.; Oswald, G.E.; Barker, R.E.

    1981-01-01

    Hydrocarbonization is a relatively simple process used for producing oil, substitute natural gas, and char by heating coal under a hydrogen-rich atmosphere. This report describes studies that were performed in a bench-scale hydrocarbonization system at Oak Ridge National Laboratory (ORNL) during the period 1975 to 1978. The results of mock-up studies, coal metering valve and flowmeter development, and supporting work in an atmospheric hydrocarbonization system are also described. Oil, gas, and char yields were determined by hydrocarbonization of coal in a 0.1-m-diam fluidized-bed reactor operated at a pressure of 2170 kPa and at temperatures ranging from 694 to 854 K. The nominal coal feed rate was 4.5 kg/h. Wyodak subbituminous coal was used for most of the experiments. A maximum oil yield of approx. 21% based on moisture- and ash-free (maf) coal was achieved in the temperature range of 810 to 840 K. Recirculating fluidized-bed, uniformly fluidized-bed, and rapid hydropyrolysis reactors were used. A series of operability tests was made with Illinois No. 6 coal to determine whether caking coal could be processed in the recirculating fluidized-bed reactor. These tests were generally unsuccessful because of agglomeration and caking problems; however, these problems were eliminated by the use of chemically pretreated coal. Hydrocarbonization experiments were carried out with Illinois No. 6 coal that had been pretreated with CaO-NaOH, Na/sub 2/CO/sub 3/, and CaO-Na/sub 2/CO/sub 3/. Oil yields of 14, 24, and 21%, respectively, were obtained from the runs with treated coal. Gas and char yield data and the composition of the oil, gas, and char products are presented.

  16. Feminization of migrations?

    Directory of Open Access Journals (Sweden)

    Morokvaši? Mirjana

    2010-01-01

    Full Text Available Women have always taken part in migrations, but their presence varied depending on their origins, on the labour market situation both in the areas of origin and in the target areas, as well as the migration policies in the immigration areas. Their presence was not always visible and did not attract as much scholarly and political attention as today. What happened, how can one explain such an interest lately, whereas only few years ago the subject was marginal, in the shadow of the "mainstream - malestream", i.e. migration as a phenomenon which focuses on geographic mobility of men, while women are not considered as equal protagonists, they either follow or remain at home. Could the so called "feminization" of migration explain the great and sudden interest for women and gender in migrations? This text critically examines the notion of "feminization" considered today as one of the main dimensions of global migration flows. Drawing on trends both globally and in specific countries, it shows that "feminization" is neither a new nor a sudden trend and entails variations depending on the origins, level of development and maturity of migration flows. In some groups men were primo-migrants and with a gradual feminization the flows reach a balanced sex ratio. There where women migrated first, or became numerically predominant, one observs the opposite trend: a "masculinization". Some authors rightly refer to "gender transition", the term which covers both trends. It is argued in the conclusion that the visibility and growing interest for women in migration and, more recently, for a gender perspective in migration, is not only due to the changing migration patterns and profile of migrants but also to the renewal of theoretical perspectives in migration and gender studies in a context that largely facilitated that renewal. The focus of our attention today on specific aspects of migration is triggered not only by genuine changes in migration trends, but it is also a result of a long process of visibilisation in the academic production on migration, women and gender. These trends may have existed earlier in the migration history but had remained in the shadow of categories defining, recording and analyzing migration.

  17. Migration and pollution

    OpenAIRE

    Jha, Raghbendra; Whalley, John

    2003-01-01

    We explore the links between migration of labour and location specific (urban) pollution, suggesting a sense in which pollution can be welfare improving. In a conventional Harris-Todaro model of urban-rural migration, individuals migrate so as to equate the expected urban wage (given a downward rigid real wage in the urban sector) to the real wage. Unemployment is endogenously determined. Interpreting unemployment as damage, urban pollution (damage denoted in units of labour) can also support...

  18. Multilateral resistance to migration

    OpenAIRE

    Bertoli, Simone; Fernández-Huertas Moraga, Jesús

    2011-01-01

    The scale of migration ows between two countries does not only depend on their relative attractiveness, but also on the one of alternative destinations. Following the trade literature, we term the influence exerted by other destinations on bilateral flows as Multilateral Resistance to Migration, and we show how it can be accounted for when estimating the determinants of bilateral migration flows in the context of a general individual random utility maximization model. We propose the use of th...

  19. Many Faces of Migrations

    OpenAIRE

    Milica Antić Gaber; Marko Krevs

    2013-01-01

    Temporary or permanent, local or international, voluntary or forced, legal or illegal, registered or unregistered migrations of individuals, whole communities or individual groups are an important factor in constructing and modifying (modern) societies. The extent of international migrations is truly immense. At the time of the preparation of this publication more than 200 million people have been involved in migrations in a single year according to the United Nations. Furthermore, three time...

  20. Hydrocarbon Distribution in Sediments from the Southeast Coastal Region of Bangladesh

    Directory of Open Access Journals (Sweden)

    Biplob Das

    2002-01-01

    Full Text Available The research deals with the study of the nature of hydrocarbons occurring at the coastal region of Bangladesh to assess the extent of hydrocarbon pollution in the marine environment. Accordingly, five sediment samples were analyzed for extraction of soluble organic matter, fractionation of extract into aliphatic hydrocarbons, aromatic hydrocarbons and polar compounds, molecular composition analysis of aromatic and aliphatic hydrocarbons? fractions and integration of results for the study of the nature and origin of hydrocarbons in the marine environment. Hydrocarbons present in the sediment samples might have originated from three main sources: a biosynthesis of aquatic organisms and/or diagenesis of alteration of bacteria, zooplankton, phytoplankton and higher plant derived organic matters; b migration of immature oil seep from deeper sources and c direct incorporation of fossil hydrocarbons discharged into the sea water by various sea-going vessels. The total hydrocarbons in five sediment samples from the study area ranged from 71.73 to 359.21ppm. Recommendations are made to take appropriate measure for the protection of the marine environment from further pollution.

  1. [Secondary dyslipidemias].

    Science.gov (United States)

    Vargová, V; Pytliak, M; Mechírová, V

    2012-03-01

    Dyslipidemias rank among the most important preventabile factors of atherogenesis and its progression. This topic is increasingly being discussed as e.g. more than 50% of Slovak population die on atherosclerotic complications. According to etiology we distinguish primary dyslipidemias with strictly genetic background and secondary ones with origin in other disease or pathological state. Secondary dyslipidemias accompany various diseases, from common (endocrinopathies, renal diseases etc) to rare ones (thesaurismosis etc.) and represents one of symptoms of these diseases. Apart from particular clinical follow up of diagnosed dysipidemias, basic screening and secondary causes as well as treatment due to updated guidelines is recuired. In this review we present the most frequent dyslipidemias of clinical practice. PMID:22486289

  2. Hydrocarbon bioremediation -- An overview

    International Nuclear Information System (INIS)

    Bioremediation is the process that transforms xenobiotics introduced into the environment to a less toxic or innocuous form, or mineralizes them to inorganic species. The processes can be carried out through either aerobic or anaerobic pathways by indigenous heterotrophs or by specially engineered organisms. For some xenobiotics, the process can also be carried out by cometabolic processes, which use another compound as the carbon and energy source. This technique can be applied either in situ or ex situ. An overview is presented of real-world applications of a variety of hydrocarbon bioremediation approaches, including biopiling, bioventing, bioslurping, landfarming, electrobioreclamation, and biovertical circulation wells. Problems in translating laboratory and field-scale pilot test data to full-scale operating systems are discussed. Such issues include biodegradation enhancement, nutrient and electron acceptor delivery, alternative electron acceptors, and integration of biological, chemical, and physical approaches to hydrocarbon remediation

  3. Regional Redistribution and Migration

    DEFF Research Database (Denmark)

    Manasse, Paolo; Schultz, Christian

    We study a model with free migration between a rich and a poor region. Since there is congestion, the rich region has an incentive to give the poor region a transfer in order to reduce immigration. Faced with free migration, the rich region voluntarily chooses a transfer, which turns out to be...... equal to that a social planner would choose. Provided migration occurs in equilibrium, this conclusion holds even in the presence of moderate mobility costs. However, large migration costs will lead to suboptimal transfers in the market solution...

  4. Direct hydrocarbon fuel cells

    Science.gov (United States)

    Barnett, Scott A.; Lai, Tammy; Liu, Jiang

    2010-05-04

    The direct electrochemical oxidation of hydrocarbons in solid oxide fuel cells, to generate greater power densities at lower temperatures without carbon deposition. The performance obtained is comparable to that of fuel cells used for hydrogen, and is achieved by using novel anode composites at low operating temperatures. Such solid oxide fuel cells, regardless of fuel source or operation, can be configured advantageously using the structural geometries of this invention.

  5. Biogeochemistry of Halogenated Hydrocarbons

    Science.gov (United States)

    Adriaens, P.; Gruden, C.; McCormick, M. L.

    2003-12-01

    Halogenated hydrocarbons originate from both natural and industrial sources. Whereas direct anthropogenic emissions to the atmosphere and biosphere are often easy to assess, particularly when they are tied to major industrial activities, the attribution of emissions to other human activities (e.g., biomass burning), diffuse sources (e.g., atmospheric discharge, run off), and natural production (e.g., soils, fungi, algae, microorganisms) are difficult to quantify. The widespread occurrence of both alkyl and aryl halides in groundwater, surface water, soils, and various trophic food chains, even those not affected by known point sources, suggests a substantial biogeochemical cycling of these compounds (Wania and Mackay, 1996; Adriaens et al., 1999; Gruden et al., 2003). The transport and reactive fate mechanisms controlling their reactivity are compounded by the differences in sources of alkyl-, aryl-, and complex organic halides, and the largely unknown impact of biogenic processes, such as enzymatically mediated halogenation of organic matter, fungal production of halogenated hydrocarbons, and microbial or abiotic transformation reactions (e.g., Asplund and Grimvall, 1991; Gribble, 1996; Watling and Harper, 1998; Oberg, 2002). The largest source may be the natural halogenation processes in the terrestrial environment, as the quantities detected often exceed the amount that can be explained by human activities in the surrounding areas ( Oberg, 1998). Since biogeochemical processes result in the distribution of a wide range of halogenated hydrocarbon profiles, altered chemical structures, and isomer distributions in natural systems, source apportionment (or environmental forensics) can often only be resolved using multivariate statistical methods (e.g., Goovaerts, 1998; Barabas et al., 2003; Murphy and Morrison, 2002).This chapter will describe the widespread occurrence of halogenated hydrocarbons, interpret their distribution and biogeochemical cycling in light of natural and anthropogenic sources, biotic and abiotic reactivity, and prevailing cycling mechanisms. Specific emphasis will be placed on the potential role of biotic and abiotic transformation reactions in soil, water, and sediment environments resulting in environmental sequestration and phase transfer.

  6. ADVANCES IN HYDROCARBON TECHNOLOGIES

    OpenAIRE

    Martin Bajus

    2007-01-01

    This paper provides an overview about today’s and future trends in using hydrocarbon technologies and related hydrogen technologies. The content of this presentation is devoted to hydrogen/bio-hydrogen production – with focus on-board fuel reforming and vehicular hydrogen storage. Hydrogen storage is widely recognized as a major technological barrier to the successful implementation of fuel cells for transportation and portable applications. The paper shows that GTL technology is undergoing a...

  7. THERMOCHEMISTRY OF HYDROCARBON RADICALS

    Energy Technology Data Exchange (ETDEWEB)

    Kent M. Ervin, Principal Investigator

    2004-08-17

    Gas phase negative ion chemistry methods are employed to determine enthalpies of formation of hydrocarbon radicals that are important in combustion processes and to investigate the dynamics of ion-molecule reactions. Using guided ion beam tandem mass spectrometry, we measure collisional threshold energies of endoergic proton transfer and hydrogen atom transfer reactions of hydrocarbon molecules with negative reagent ions. The measured reaction threshold energies for proton transfer yield the relative gas phase acidities. In an alternative methodology, competitive collision-induced dissociation of proton-bound ion-molecule complexes provides accurate gas phase acidities relative to a reference acid. Combined with the electron affinity of the R {center_dot} radical, the gas phase acidity yields the RH bond dissociation energy of the corresponding neutral molecule, or equivalently the enthalpy of formation of the R{center_dot} organic radical, using equation: D(R-H) = {Delta}{sub acid}H(RH) + EA(R) - IE(H). The threshold energy for hydrogen abstraction from a hydrocarbon molecule yields its hydrogen atom affinity relative to the reagent anion, providing the RH bond dissociation energy directly. Electronic structure calculations are used to evaluate the possibility of potential energy barriers or dynamical constrictions along the reaction path, and as input for RRKM and phase space theory calculations. In newer experiments, we have measured the product velocity distributions to obtain additional information on the energetics and dynamics of the reactions.

  8. From Immigration to Migration Systems: New Concepts in Migration History.

    Science.gov (United States)

    Hoerder, Dirk

    1999-01-01

    Describes the characteristics of migration systems where two or more societies are connected through migration patterns. Identifies the four major migration systems that populated North America. Reviews the literature in relation to migration systems and discusses autobiographical accounts of migration. Provides an extensive bibliography. (CMK)

  9. Cloud migration research: a systematic review

    OpenAIRE

    Jamshidi, Pooyan; Ahmad, Aakash; Pahl, Claus

    2013-01-01

    BACKGROUND--By leveraging cloud services, organizations can deploy their software systems over a pool of resources. However, organizations heavily depend on their business-critical systems, which have been developed over long periods. These legacy applications are usually deployed on-premise. In recent years, research in cloud migration has been carried out. However, there is no secondary study to consolidate this research. OBJECTIVE--This paper aims to identify, taxonomically classify an...

  10. Migration, klima og sundhed

    DEFF Research Database (Denmark)

    Tellier, Siri; Carballo, Manuel

    2009-01-01

    Many tentative connections have been postulated between migration and climate. This article points to rural-urban migration, particularly into low elevation urban slums prone to flooding as an issue needing urgent attention by health professionals. It also notes the no-man's land in which...

  11. Samtidskunst og migration

    DEFF Research Database (Denmark)

    Petersen, Anne Ring

    2010-01-01

    "Samtidskunst og migration. En oversigt over faglitteraturen" er en forskningsoversigt der gør status over hvad der hidtil er skrevet inden for det kunsthistoriske område om vor tids billedkunst og migration som politisk, socialt og kulturelt fænomen, primært i forbindelse med immigration til...

  12. Migration, Narration, Identity

    DEFF Research Database (Denmark)

    Leese, Peter

    (co-editor with Carly McLaughlin and Wladyslaw Witalisz) This book presents articles resulting from joint research on the representations of migration conducted in connection with the Erasmus Intensive Programme entitled «Migration and Narration» taught to groups of international students over...

  13. Migrating Art History

    DEFF Research Database (Denmark)

    Ørum, Tania

    2012-01-01

    Review of Hiroko Ikegami, The Great Migrator. Robert Rauschenberg and the Global Rise of American Art. Cambridge Mass., The MIT Press, 2010. 277 pages. ISBN 978-0-262-01425-0.......Review of Hiroko Ikegami, The Great Migrator. Robert Rauschenberg and the Global Rise of American Art. Cambridge Mass., The MIT Press, 2010. 277 pages. ISBN 978-0-262-01425-0....

  14. Environmental change and migration.

    Czech Academy of Sciences Publication Activity Database

    Stojanov, Robert

    Santa Barbara, Calif : Praeger, 2012 - (Segal, U.; Elliot, D.), s. 55-89 ISBN 978-0-313-37807-2 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073 Institutional research plan: CEZ:AV0Z60870520 Keywords : migration processes * environmental change * climate change * environmental migrants * human migration Subject RIV: AO - Sociology, Demography

  15. World Migration Degree Global migration flows in directed networks

    CERN Document Server

    Porat, Idan

    2015-01-01

    In this article we analyze the global flow of migrants from 206 source countries to 145 destination countries (2006-2010) and focus on the differences in the migration network pattern between destination and source counters as represented by its degree and weight distribution. Degree represents the connectivity of a country to the global migration network, and plays an important role in defining migration processes and characteristics. Global analysis of migration degree distribution offers a strong potential contribution to understanding of migration as a global phenomenon. In regard to immigration, we found that it is possible to classify destination countries into three classes: global migration hubs with high connectivity and high migration rate; local migration hubs with low connectivity and high migration rate; and local migration hubs with opposite strategy of high connectivity and low migration rate. The different migration strategies of destination countries are emerging from similar and homogenies p...

  16. On marriage and migration.

    Science.gov (United States)

    Stark, O

    1988-09-01

    Marriage, migration, and related phenomena such as marital stability, fertility, and investment in human capital may be better explained by studying marriage and migration jointly. This paper examines the role of migration in obtaining joint labor market and marriage market equilibrium. When broadly interpreted, marriage and migration share a number of common features. Both involve search and its resolution (pairing of mates in the former and matching of labor and firms in the latter). In both cases, success in finding a partner is sensitive to the availability of partners and to the distribution of their endowments and traits. Almost always, and along with separation and divorce, marriage mandates spatial relocation which may translate into migration. Both involve a movement that is associated with adjustment costs from 1 state into another. The decisions to enter marriage and undertake employment or the decisions to divorce and quit a job depend on exogenous parameters, some of which are determined by the marriage market and the labor market. Since both marriage and divorce take place in the context of broadly defined markets, they may and often are analyzed applying market concepts, theorems, and solutions. Yet the authors could not pinpoint 1 single, systematic attempt that checks through the interactions between marriage and migration, so this paper attempts to rectify this state of research. Essentially, this paper 1) discusses individual decision making pending possible migration prior to or following marriage, 2) examines whether it is easier for a married couple or a single person to migrate, and 3) considers whether marriage dissolution could cause migration when marriage is the only reason that has kept a spouse from moving. This integrated research agenda for both marriage and migration can delineate interesting new implications to examine. PMID:12158993

  17. A dengue model incorporating saturation incidence and human migration

    Science.gov (United States)

    Gakkhar, S.; Mishra, A.

    2015-03-01

    In this paper, a non-linear model has been proposed to investigate the effects of human migration on dengue dynamics. Human migration has been considered between two patches having different dengue strains. Due to migration secondary infection is possible. Further, the secondary infection is considered in patch-2 only as strain-2 in patch-2 is considered to be more severe than that of strain-1 in patch-1. The saturation incidence rate has been considered to incorporate the behavioral changes towards epidemic in human population. The basic reproduction number has been computed. Four Equilibrium states have been found and analyzed. Increasing saturation rate decreases the threshold thereby enhancing the stability of disease-free state in both the patches. Control on migration may lead to change in infection level of patches.

  18. Measuring Trace Hydrocarbons in Silanes

    Science.gov (United States)

    Lesser, L. A.

    1984-01-01

    Technique rapid and uses standard analytical equipment. Silane gas containing traces of hydrocarbons injected into carrier gas of moist nitrogen having about 0.2 percent water vapor. Carrier, water and silane pass through short column packed with powdered sodium hydroxide which combines moisture and silane to form nonvolatile sodium silicate. Carrier gas free of silane but containing nonreactive hydrocarbons, pass to silica-gel column where chromatographic separation takes place. Hydrocarbons measured by FID.

  19. Material erosion and migration in tokamaks

    International Nuclear Information System (INIS)

    Material migration is one of the outstanding issues facing successful long pulse, high power tokamak operation, both for the next step device, ITER, and the longer term economic and technological viability of fusion power. Erosion of tokamak first wall surfaces may occur via a number of processes, both steady state and transient, the relative importance of each of which depends sensitively on the nature of the driving mechanism and the wall material itself. The subsequent transport of this eroded material through the plasma and its redeposition, often in locations remote from the point of release, constitute the foundation of material migration. Such material movement is intimately linked with the critical issue of tritium retention (via the process of co-deposition), which, in ITER and beyond, will determine the duration over which the tokamak may be operated before removal of the retained fraction is imposed by nuclear safety restrictions. Of the three processes: erosion, large-scale material transport and co-deposition, transport is currently the least understood, leading to large uncertainties in the predicted T-retention in ITER, independently of the chosen wall materials. The low duty cycle and reduced energy and particle fluxes to first wall surfaces in today's tokamaks mean that the phenomena of migration is of no practical consequence to their operation. In steady state reactor-class devices, however, annual migration rates are currently predicted to be in the range of tons, even in the absence of transient events. These estimates are nevertheless associated with considerable uncertainty and, although the situation is unlikely to be completely resolved by the time ITER is constructed, a clearer understanding of the global migration picture is emerging from ongoing physics studies in current devices. In particular, the influential role of erosion at main chamber surfaces, followed by subsequent transfer to the divertor and the delicate erosion/deposition balance in the divertor itself is now recognised, even though the use of carbon in many tokamaks adds significant complexity to the problem through the requirement to account for hydrocarbon chemistry. This contribution aims both to review our current understanding of erosion and migration by compiling current experimental and modelling results, and to discuss key areas of uncertainty preventing the accurate prediction of migration rates in ITER and future reactors. Plans for a large scale investigation of migration and T-retention at JET with the hitherto untested ITER first wall material mix will also be discussed. (Author)

  20. ADVANCES IN HYDROCARBON TECHNOLOGIES

    Directory of Open Access Journals (Sweden)

    Martin Bajus

    2007-07-01

    Full Text Available This paper provides an overview about today’s and future trends in using hydrocarbon technologies and related hydrogen technologies. The content of this presentation is devoted to hydrogen/bio-hydrogen production – with focus on-board fuel reforming and vehicular hydrogen storage. Hydrogen storage is widely recognized as a major technological barrier to the successful implementation of fuel cells for transportation and portable applications. The paper shows that GTL technology is undergoing a renewal of its innovative process. For more detailed information the interested reader is invited to consult the dedicated papers cited throughout the overview.

  1. Suicidal Ideation and Migration Aspirations among Youth in Central Mexico

    OpenAIRE

    Steven Hoffman

    2013-01-01

    Over the past 100 years the state of Guanajuato has consistently been one of the highest migrant sending states in Mexico. Youth living in high migratory states such as Guanajuato are heavily influenced by the expectation that they will travel to the US, and research has shown that those who do not migrate may be looked down upon by members of their community. This secondary analysis looks at the connection between suicidal ideation and migration aspirations among a group of adolescents livin...

  2. Wnts induce migration and invasion of myeloma plasma cells

    OpenAIRE

    Qiang, Ya-Wei; Walsh, Katie; Yao, Lei; Kedei, Noemi; Blumberg, Peter M; Rubin, Jeffrey S.; Shaughnessy, John; Rudikoff, Stuart

    2005-01-01

    Multiple myeloma is an incurable form of lymphoid cancer characterized by accumulation of neoplastic plasma cells in the bone marrow cavity. Little is known about the mechanisms regulating myeloma cell movement within the bone marrow and metastasis to secondary sites. Herein, we identify multiple members of the wingless/int (Wnt) family as promoters of myeloma cell migration/invasion. Wnt-mediated migration was associated with the Wnt/RhoA pathway and did not necessitate signaling through ?-c...

  3. Characterization of hydrocarbon contaminated areas by multivariate statistical analysis: Case studies.

    Science.gov (United States)

    Saenz, G; Pingitore, N E

    1991-01-01

    Analysis of soil gases is a relatively rapid and inexpensive method to delineate and measure hydrocarbon contamination in the subsurface caused by diesel or gasoline. Techniques originally developed for petroleum exploration have been adapted to tracking hydrocarbons which have leaked or spilled at or below the earth's surface.Discriminant analysis (a multivariate statistical technique) is used to classify soil gas samples of C1 to C7 hydrocarbons as biogenic (natural soil gases) or thermogenic (contaminant hydrocarbons). Map plots of C1 to C7 total interstitial hydrocarbons, C2 to C7 interstitial hydrocarbons, and C1/?C n rations are used to further delineate and document the extent and migration of contamination.Three case studies of the technique are presented: each involves leakage of hydrocarbons from underground storage tanks. Soil gas analysis clearly defines the spread of contamination and can serve as the basis for the correct placement of monitoring wells. The method proved to be accurate, rapid, and cost-effective; it therefore has potential for widespread application to the identification of soil and groundwater contaminated by hydrocarbons. PMID:24233510

  4. Labor migration in Asia.

    Science.gov (United States)

    Martin, P L

    1991-01-01

    "A recent conference sponsored by the United Nations Center for Regional Development (UNCRD) in Nagoya, Japan examined the growing importance of labor migration for four major Asian labor importers (Japan, Hong Kong, Malaysia, and Singapore) and five major labor exporters (Bangladesh, Korea, Pakistan, Philippines, and Thailand).... The conference concluded that international labor migration would increase within Asia because the tight labor markets and rising wages which have stimulated Japanese investment in other Asian nations, for example, have not been sufficient to eliminate migration push and pull forces...." PMID:12316776

  5. Determinants of Migration, Revisited

    OpenAIRE

    Alexander, Gigi; Foley, Maggie

    2014-01-01

    This empirical study investigates the impact on net state in-migration over the 2000-2003 period of a variety of economic and non-economic factors and thereby serves as a robustness test of previous studies. The empirical estimates indicate that the net state in-migration rate was an increasing function of median family income or expected median family income on the one hand and a decreasing function of the average cost of living. In addition, net state in-migration was an increasing function...

  6. Thermophysical Properties of Hydrocarbon Mixtures

    Science.gov (United States)

    SRD 4 NIST Thermophysical Properties of Hydrocarbon Mixtures (PC database for purchase)   Interactive computer program for predicting thermodynamic and transport properties of pure fluids and fluid mixtures containing up to 20 components. The components are selected from a database of 196 components, mostly hydrocarbons.

  7. [Cilia and neuronal migrations].

    Science.gov (United States)

    Métin, Christine

    2014-11-01

    In a landmark paper published in 1977, G. Albrecht-Buehler described a primary cilium on the surface of migrating fibroblasts, and noticed that cilia are oriented parallel to the direction of migration of fibroblasts. While the presence of a primary cilium on neural progenitors and on post-mitotic neurons was noted long ago, it has been observed on migrating cortical interneurons only recently. As in fibroblasts, the cilium of interneurons controls the directionality of migration. It plays an important role in the reorientation of cortical interneurons towards the cortical plate. The morphogen Shh, which is expressed in the migratory pathway of interneurons, is one of the signals that control this reorientation. PMID:25388581

  8. Global Governance of Migration

    OpenAIRE

    Rustamov, Sirus

    2011-01-01

    The aim of this thesis is to analyze the recently formed global governance of migration, which has got an unprecedented trans-boundary nature due to the impacts og globalization in the post Cold War era. 

  9. Migration og etnicitet

    DEFF Research Database (Denmark)

    Christiansen, Connie Carøe

    Migration og etnicitet er aktuelle og forbundne fænomener, idet migration øger berøringsfladerne mellem befolkningsgrupper. Etniciteter formes i takt med at grænser drages imellem disse grupper. Imod moderniserings-teoriernes forventning forsvandt etnicitet ikke som en traditionel eller oprindelig...... måde at skabe tilhørsforhold på; globalt set fremstår vor tid istedet som en "migrationens tidsalder", der tilsyneladende også er en tidsalder, hvor kulturelle særtræk, i form af etnicitet, udgør vigtige linjer, hvorefter grupper skilller sig ud fra hinanden. Både migration og etnicitet bringer fokus...... den finder sted i modtagerlandet, men nyere perspektiver på migration, som begreber om medborgerskab, transnationalisme og diaspora er eksponenter for, søger udover den nationalstatslige ramme og inddrager konsekvenserne af migrationen for afsenderlande....

  10. Migration = cloning; aliasiing

    DEFF Research Database (Denmark)

    Hüttel, Hans; Kleist, Josva; Nestmann, Uwe; Merro, Massimo

    In Obliq, a lexically scoped, distributed, object-oriented programming language, object migration was suggested as the creation of a copy of an object’s state at the target site, followed by turning the object itself into an alias, also called surrogate, for the remote copy. We consider the...... creation of object surrogates as an abstraction of the abovementioned style of migration. We introduce Øjeblik, a distribution-free subset of Obliq, and provide three different configuration-style semantics, which only differ in the respective aliasing model. We show that two of the semantics, one of which...... matches Obliq’s implementation, render migration unsafe, while our new proposal for a third semantics is provably safe. Our work suggests a straightforward repair of Obliq’s aliasing model such that it allows programs to safely migrate objects....

  11. Ambient aromatic hydrocarbon measurements at Welgegund, South Africa

    OpenAIRE

    K. Jaars; Beukes, J. P.; Zyl, P. G. van; A. D. Venter; Josipovic, M; Pienaar, J. J.; Vakkari, V.; H. Aaltonen; Laakso, H.; Kulmala, M; Tiitta, P.; Guenther, A.; Hellén, H.; L. Laakso; Hakola, H.

    2014-01-01

    Aromatic hydrocarbons are associated with direct adverse human health effects and can have negative impacts on ecosystems due to their toxicity, as well as indirect negative effects through the formation of tropospheric ozone and secondary organic aerosol that affect human health, crop production and regional climate. Measurements were conducted at the Welgegund measurement station (South Africa) that is considered to be a regionally representative backgroun...

  12. Hydrocarbon potential of Ordovician and Silurian rocks. Siljan Region (Sweden)

    Energy Technology Data Exchange (ETDEWEB)

    Berner, U. [Bundesanstalt fuer Geowissenschaften und Rohstoffe (BGR), Hannover (Germany); Lehnert, O. [Erlangen-Nuernberg Univ., Erlangen (Germany); Meinhold, G. [Goettingen Univ. (Germany)

    2013-08-01

    Hydrocarbon exploration in the vicinity of Europe's largest impact structure (Siljan, Central Sweden) focused for years on abiogenic concepts and largely neglected state of the art knowledge on hydrocarbon generation via thermal decomposition of organic matter. In our study we use sedimentary rocks obtained from three drill sites (Mora001, Stumsnaes 1 and Solberga 1) within the ring structure around the central uplift to investigate the hydrocarbon potential of Ordovician and Silurian strata of the region and also for comparison with the shale oil and gas potential of age equivalent rocks of the Baltic Sea. Elemental analyses provided information on concentrations of carbonate and organic carbon, total sulfur as well as on the composition of major and minor elements of the sediments. The data has been used to evaluate the depositional environment and possible diagenetic alterations of the organic matter. RockEval pyrolysis and solvent hydrocarbon extraction gave insight into the hydrocarbon generation potential and the type and thermal maturity of the sediments. From the geochemistry data of the studied wells it is obvious that changes of depositional environments (lacustrine - marine) have occurred during Ordovician and Silurian times. Although, the quality of the organic matter has been influenced in marine and brackish environments through sulfate reduction, we observe for a number of marine and lacustrine sediments a good to excellent preservation of the biological precursors which qualify the sediments as hydrocarbon source rocks (Type II kerogens). Lacustrine source rocks show a higher remaining hydrocarbon potential (up to {proportional_to}550 mg HC per g C{sub org}) than those of marine or brackish environments. Our investigations indicate that the thermal maturity of organic matter of the drill sites has reached the initial stage of oil generation. However, at Mora001 some of the sediments were stained with oil indicating that hydrocarbons have migrated from more mature parts of the Siljan structure into the marginally mature sediments. Likely sources could have been the Upper Ordovician Fjaecka Shale deposited in a brackish to lacustrine environment or the Lower Silurian Kallholm Fm. of similar environments which both have an excellent hydrocarbon potential for oil and gas. Marine source rocks of the Siljan region may be compatible to unconventional shale targets of the German region of the Baltic Sea provided appropriate thermal maturities are not exceeded.

  13. Employment Protection and Migration

    OpenAIRE

    Bazillier, Rémi; Moullan, Yasser

    2012-01-01

    We argue in this paper that labor market institutions, and more particularly employment protection (EPL), are an important determinant of migration. Using a bilateral migration database, we empirically show that the employment protection di fferential has a negative impact on bilateral ows. Contrary to pop- ular wisdom which assumes that migrants look for a more protected market, we show that migrants tend to move to countries where employment protection is close to that of their country of o...

  14. Migration and culture

    OpenAIRE

    Epstein, Gil S.; Gang, Ira N.

    2010-01-01

    Culture is not new to the study of migration. It has lurked beneath the surface for some time, occasionally protruding openly into the discussion, usually under some pseudonym. The authors bring culture into the open. They are concerned with how culture manifests itself in the migration process for three groups of actors: the migrants, those remaining in the sending areas, and people already living in the recipient locations. The topics vary widely. What unites the authors is an understanding...

  15. Essays on international migration

    OpenAIRE

    Chowdhury, Mehdi Mahmud

    2011-01-01

    In recent time efforts are observed in re-evaluating the linkage between economic development and international migration. The thesis can be considered as an attempt to add something to those efforts. In this thesis we mainly analyse the effects of competition among the countries in international labour market and effects of migration on the research activities of firms. As appeared, these two issues so far have not received much attention of economic literature. We analyse the above men...

  16. Religion, migration og integration

    DEFF Research Database (Denmark)

    Borup, Jørn

    Sammenhængen mellem religion og integration har de sidste år været genstand for debat. Artiklen kommer ind på begreber og sammenhænge relateret til området (migration, diaspora, assimilation, etnicitet, kultur) og ser på religionens mulige rolle som negativ eller positiv ressource i integrationss......Sammenhængen mellem religion og integration har de sidste år været genstand for debat. Artiklen kommer ind på begreber og sammenhænge relateret til området (migration, diaspora, assimilation, etnicitet, kultur) og ser på religionens mulige rolle som negativ eller positiv ressource i...

  17. Migration and Place Attractiveness

    OpenAIRE

    Niedomysl, Thomas

    2006-01-01

    The thesis includes six self-contained papers that from various perspectives examine place attractiveness and migration in Sweden. Paper I provides an extensive overview of Swedish municipalities’ place marketing engagement to attract in-migrants, based on survey responses from 220 municipalities. The results suggest that, although this kind of marketing has become more prominent during the last few years, there is little evidence of any significant effects on migration flows. Paper II addr...

  18. Migrations et changements climatiques

    OpenAIRE

    Piguet, Etienne; Pécoud, Antoine; de Guchteneire, Paul

    2010-01-01

    Cet article propose un tour d’horizon des débats relatifs aux possibles conséquences migratoires du changement climatique. Après un bref historique, nous examinons l'impact sur les migrations des trois principaux facteurs environnementaux liés aux changements climatiques (cyclones tropicaux, fortes pluies et inondations ; sécheresses et désertification ; élévation du niveau de la mer). Les questions fondamentales que soulève la relation entre changement climatique et migration sont ensuite ab...

  19. Making migration safer

    OpenAIRE

    Thieme, S; A. Ghimire; Gurung, G

    2009-01-01

    In a globalising market, labour migration in low-skilled sectors plays a particularly important role. A growing number of poor people move between their villages of origin, the capital and international destinations, while financially sustaining their families and regions. The positive role of remit- tances for alleviating the poverty of sending countries is widely acknowledged. However, migration also leads to a growing imbalance between rural and urban areas and unfavourable societal change...

  20. Making migration safer [updated

    OpenAIRE

    Thieme, Susan; Ghimire, Anita; Gurung, Ganesh

    2014-01-01

    In a globalising market, labour migration in low-skilled sectors plays an important role. A growing number of poor people move between their villages of origin, capital cities, and international destinations, while financially sustaining their families and home countries. The positive role of remittances for alleviating the poverty of sending countries is widely acknowledged. However, migration also leads to a growing imbalance between rural and urban areas and certain unfavourable societal c...

  1. Ex-situ bioremediation of polycyclic aromatic hydrocarbons in sewage sludge

    DEFF Research Database (Denmark)

    Larsen, Sille Bendix; Karakashev, Dimitar Borisov; Angelidaki, Irini; Schmidt, Jens Ejbye

    2009-01-01

    Polycyclic aromatic hydrocarbons (PAH) are regarded as environmental pollutants. A promising approach to reduce PAH pollution is based on the implementation of the natural potential of some microorganisms to utilize hydrocarbons. In this study Proteiniphilum acetatigenes was used for bioaugmentation of sewage sludge to improve the PAH removal. Bioaugmentation experiments were performed in parallel semi-continuously fed reactors started up with digested primary and secondary sludge. Three bioaugm...

  2. Migration and malaria.

    Science.gov (United States)

    Jitthai, Nigoon

    2013-01-01

    Migration is an important global issue as poorly managed migration can result in a diversity of problems, including an increase in the transmission of diseases such as malaria. There is evidence to suggest that malaria is no longer a forest-dependent disease and may largely be affected by population movements, mostly to agricultural areas. While internal and transnational migration has different legal implications in most countries, both types of migration occur for the same reasons; economic and/ or safety. Although migration in itself is not a definitive risk for malaria, several factors can put, migrants and local communities alike, in vulnerable situations. In particular, infrastructure and rural development, deforestation for logging and economic farming, political movements, and natural disasters are some of the major factors that push and pull people in and out of malaria-endemic areas. Therefore, understanding the changing socio-environmental situation as well as population movements and their associated risks for malaria infection, is critical for malaria control, containment, and elimination. Efforts to address these issues should include advocacy, mapping exercises and expanded/ strengthened surveillance to also include migrant health information systems. Malaria related information, prevention measures, and early diagnosis and appropriate treatment should be made easily accessible for migrants regardless of their migration status; not only to ensure that they are equipped with appropriate knowledge and devices to protect themselves, but also to ensure that they are properly diagnosed and treated, to prevent further transmission, and to ensure that they are captured by the surveillance system. PMID:24159832

  3. Optrode for sensing hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Miller, H.; Milanovich, F.P.; Hirschfeld, T.B.; Miller, F.S.

    1987-05-19

    This patent describes an article of manufacture an optrode for chemically sensing halogenated hydrocarbons comprising the elements: a capillary tube capped at one end by a semipermeable membrane of porous membrane; a fiber optic attached at a distal end thereof to a second end of the capillary tube by attaching means. The fiber optic extends into the capillary tube. A proximal end of the fiber optic is connected to an illumination source and a detector means; a column of a first reagent comprises pyridine or a pyridine derivative disposed in the capillary tube adjacent the capped end; and a column of a second reagent comprises an alkali disposed in the capillary tube adjacent to and in contact with the column of the first reagent such that a surface of contact between the alkali and the first reagent is adjacent the distal end of the fiber optic.

  4. Halogenated aliphatic hydrocarbon nephrotoxicity

    International Nuclear Information System (INIS)

    Dietary ingestion of polybrominated biphenyls (PBB) and polychlorinated biphenyls (PCB) increased renal and hepatic aryl hydrocarbon hydroxylase (AHH) activities in a dietary concentration-dependent manner. Mixed-function oxidase (MFO) activities were also induced in liver and kidney by i.p. administration of 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD) and 3-methylcholanthrene (3MC), but sodium phenobarbital (NaPb) increased hepatic MFO activities only. Renal and hepatic AHH activities and cytochrome P-450 (P-450) concentrations is male, Fischer 344 rats were increased by treatments with PBB, PCB and 3MC. NaPb increased hepatic AHH activity and P-450 content only. The rates of increase (and decline to normal values) of AHH activities following single oral doses of PBB, PCB, and 3MC were much greater in the kidneys than in the liver

  5. Canada's hydrocarbon processing evolution

    International Nuclear Information System (INIS)

    The development of petroleum refining, petrochemicals and natural gas industries in Canada are discussed together with future issues and prospects. Figures give data on (a) refined products trade 1998; (b) refining capacity; (c) product demand 1980-1999; (d) refinery crude runs and capacity; (e) refining and marketing, historical returns 1993-1999; (f) processing power index for Canada and USA; (g) ethylene capacity; (eye) Montreal petrochemical capacities; (j) Sarnia petrochemical capacities in 2000; (k) Alberta petrochemicals capacities 2001; (l) ethylene net equivalent trade; (m) ethylene costs 1999 for W. Canada and other countries. It was concluded that the hydrocarbon processing business continues to expand in Canada and natural gas processing is likely to increase. Petrochemicals may expand in W. Canada, possibly using feed stock from the Far North. Offshore developments may stimulate new processing on the E. Coast

  6. Hydrocarbon potential of Middle Eocene carbonates, Sirt Basin, Libya

    Science.gov (United States)

    Swei, Giuma H.; Tucker, Maurice E.

    2015-11-01

    Deposition of Middle Eocene carbonates in the Sirt Basin in Libya has been the subject of considerable study in recent years because of the importance of sediments of this age as hydrocarbon reservoirs. The Gialo Formation is an important gas-producing reservoir in the Assumood, Sahl and other nearby fields. The gas which is generated from the gas-prone Sirt Shale source rock of the northern Ajdabiya Trough probably migrated in to the Assumood Ridge from the northeast through late Cretaceous, Paleocene and early Eocene carbonates, before being trapped beneath the Augila Shale (Upper Eocene) which is the principal regional seal in the area. This integrated study has enhanced our understanding of reservoir heterogeneity and hydrocarbon potential of the Gialo carbonates and should lead to improved exploration in the future. Reservoir quality in the Gialo Formation is a function of grain types, pore types, grain size, sorting, cementation and compaction, and predicting areas of high reservoir quality has proved difficult; exploration should be oriented to positioning wells into the main trend of the mid-ramp, nummulite accumulation. Different nummulite facies can be reservoirs depending on their diagenetic history. A diagenetic reduction in porosity must be distinguished from a lack of porosity resulting from an unfavourable depositional environment, so that exploration alternatives can be assessed. This integrated study has demonstrated the presence of suitable reservoir rocks, hydrocarbon traps and the close proximity of potential source rocks. These features should encourage further hydrocarbon exploration in the area.

  7. Mechanics of vacuum-enhanced recovery of hydrocarbons

    International Nuclear Information System (INIS)

    A growing body of field data demonstrates the enhancement of product recovery that can be achieved by applying a partial vacuum to recovery wells. Typical explanations for the observed improvement in performance invoke an increased slope of the cone of depression created in the water-table surface. Explanations related to water-table slope do not consider the gradient induced in the hydrocarbon by virtue of the airflow. Also, the airflow may induce a gradient in the aqueous phase that is not reflected in a water-table drawdown. The equations for steady-state flow of three immiscible fluids elucidate the fundamental mechanics of vacuum-enhanced recovery or bioslurping. Airflow to the recovery well causes hydrocarbon to migrate toward the well, independent of any gravity effects that may be created. Also, the relative permeability to hydrocarbon is affected by both water and airflow in the vicinity of the recovery well. Two critical airflow rates delineate the conditions for which only air is recovered, air and hydrocarbon are recovered, and all three phases are recovered

  8. Hydrocarbon refining process

    Energy Technology Data Exchange (ETDEWEB)

    Ackelson, D.B.; Moorehead, E.L.; Ward, J.W.; Probst, J.D.

    1987-09-22

    This patent describes a process for reducing the pour point of a fuel oil with minimum degradation of the viscosity. The process consists of: (1) hydrotreating a sulfur, nitrogen, and hydrocarbon-containing feedstock having an initial boiling point between about 500/sup 0/ and 600/sup 0/F and an end point between about 850/sup 0/ and 950/sup 0/F in the presence of a particulate hydrotreating catalyst. It comprises hydrogenation components on a porous refractory oxide support under conditions of elevated temperature and pressure and the presence of hydrogen so as to decrease the sulfur and nitrogen content of the feedstock; (2) hydrodewaxing at least a portion of the hydrotreated feedstock in the presence of a particulate hydrodewaxing catalyst under conditions of elevated temperature and pressure. The presence of hydrogen produces a hydrocarbon fraction of lower pour point than the fuel oil. The hydrodewaxing catalyst comprises one or more hydrogenation components on a support comprising at least 70 weight percent of an intermediate pore molecular sieve having cracking activity, and the fraction having a viscosity within about 1.75 centistokes, as measured at 212/sup 0/F, of the viscosity of the feedstock; (3) hydrotreating the entire effluent from the hydrodewaxing in the presence of hydrogen and under conditions of elevated temperature and pressure and in the presence of a particulate hydrotreating catalyst comprising one or more hydrogenation components on a porous refractory oxide support; (4) recovering the fraction from the product of the hydrotreating in step (3); and (5) blending the fraction with a fuel oil of higher pour point so as to reduce the pour point thereof while not substantially changing the viscosity of the fuel oil.

  9. Fractionation of Hydrocarbons Between Oil and Gas Phases Fractionnement des hydrocarbures entre les phases huile et gaz

    OpenAIRE

    Ruffier-Meray V.; Ungerer P.; Carpentier B.; Courcy J. P.

    2006-01-01

    The investigation of hydrocarbon fractionation between oil and gas phases is of interest for several purposes in reservoir exploitation. In reservoir geochemistry, the evolution of light hydrocarbon fractions of oils may explain some migration phenomena. In gas injection projects, the preferred dissolution of some components in gas may alter the composition as well as the properties of the oil. Underground gas storage in depleted oil reservoirs may also be concerned by these problems. Results...

  10. Membranous nephropathy following exposure to volatile hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Ehrenreich, T.; Yunis, S.L.; Churg, J.

    1977-01-01

    Excessive exposure to solvents has long been known to cause renal tubular disease in man. Recently, the occurrence of glomerular disease such as Goodpasture's syndrome with proliferative and extracapillary glomerulonephritis has been related to hydrocarbon exposure. This report concerns four patients with membranous nephropathy who had a history of prolonged exposure to a number of volatile hydrocarbons. Membranous nephropathy is a chronic renal disease involving glomeruli and occurring principally in adults. Its clinical onset is insidious and is manifested by proteinuria or edema. Proteinuria is the hallmark of the disease and may be present for many years without symptoms. It is often a slowly progressive disease. About one-fourth of the patients improve clinically and lose their proteinuria, while up to one-fourth develop renal failure. The glomerular capillary wall lesions are distinctive, contain deposits of immunoglobulin and complement considered to represent immune-complexes, and show a morphological progression from early Stage I to late Stage IV. While in most cases there is no known etiology, in some patients the disease has been deemed to be secondary to specific diseases or agents such as infections, neoplasms, or chemicals. The four cases described fall into this last category.

  11. Development of isotope techniques for hydrocarbon exploration

    International Nuclear Information System (INIS)

    A gas preparation line has been constructed to measure D/H- in addition to 13C/12C-ratios on minute quantities of methane (down to 50 ?l CH4) from well samples. The gas oxidation line was tested with samples from 3 wells from the S. German Molasse and the Rhine Valley. Hydrogen isotopes distinguish between gases of thermogenic origin and those from the different methanogenic pathways. The combination of carbon and hydrogen isotopes is useful to classify gases affected by secondary processes such as oxidation or mixing. The maturity of the source rocks generating the gases can also be estimated using carbon and hydrogen isotopes. A previously unknown biogenic methane group has been identified which is depleted strongly in both deuterium and carbon-13. Additionally, a new genetic gas type was observed with dD -40 per mille, and with higher hydrocarbons present. (orig.)

  12. Prestack depth migration

    International Nuclear Information System (INIS)

    Two lines form the southern North Sea, with known velocity inhomogeneities in the overburden, have been pre-stack depth migrated. The pre-stack depth migrations are compared with conventional processing, one with severe distortions and one with subtle distortions on the conventionally processed sections. The line with subtle distortions is also compared with post-stack depth migration. The results on both lines were very successful. Both have already influenced drilling decisions, and have caused a modification of structural interpretation in the respective areas. Wells have been drilled on each of the lines, and well tops confirm the results. In fact, conventional processing led to incorrect locations for the wells, both of which were dry holes. The depth migrated sections indicate the incorrect placement, and on one line reveals a much better drilling location. This paper reports that even though processing costs are high for pre-stack depth migration, appropriate use can save millions of dollars in dry-hole expense

  13. Diffusion of hydrocarbons from HDPE and f-HDPE geomembranes

    Energy Technology Data Exchange (ETDEWEB)

    Lindsay, H.J. [AMEC Earth and Environmental Ltd., Mississauga, ON (Canada); Rowe, K. [Royal Military Coll. of Canada, Kingston, ON (Canada). GeoEngineering Centre

    2005-07-01

    Geomembrane liners are used in landfills to prevent the migration of contaminants. They are also used at storage tank sites to control the impact of past spills and to minimize potential damage from future spills. Although high density polyethylene (HDPE) geomembranes are relatively impermeable to the actual flow of liquids, studies have shown that some organic contaminants can readily diffuse through them. The diffusion of volatile organic compounds (VOCs) such as benzene, toluene and xylenes from an aqueous solution can be reduced significantly by applying a fluorine layer to the surface of a conventional HDPE geomembrane. This study examined the potential diffusion of hydrocarbons from HDPE and fluorinated HDPE (f-HDPE) geomembranes when exposed to solvents such as neat methanol, Jet fuel A-1 dissolved in methanol, and neat Jet fuel A-1. Immersion tests were performed for each solvent. The hydrocarbon content of the samples was monitored in order to determine the effect of the solvent on the geomembrane. In the methanol immersion test, heavier hydrocarbons diffused from the geomembrane. It was found that hydrocarbon fraction of Jet fuel A-1 changed when exposed to both conventional HDPE and fluorinated HDPE geomembranes. When HDPE and f-HDPE geomembranes were immersed in methanol, hydrocarbons diffused out of the geomembranes and into the methanol. HDPE and f-HDPE geomembranes immersed in Jet A-1 and Jet A-1 dissolved in methanol. The hydrocarbon distribution changed relative to that of the original solvent/solution. Experiments performed on neat Jet A-1 resulted in an increase in the lightest fraction compared to Jet A-1 standard. When Jet A-1 was dissolved in methanol, there were changes to the lowest examined hydrocarbon fraction and the heavier carbon fractions. Hydrocarbons were found to diffuse out of both HDPE and f-HDPE geomembranes exposed to high concentrations or neat solvents. It was concluded that the results from sorption, desorption and diffusion tests on neat solutions should be interpreted with caution because the outward diffusion of waxes may result in misinterpretation of the data. 19 refs., 3 tabs., 9 figs.

  14. Quandary of migrated IUCD

    Directory of Open Access Journals (Sweden)

    Divya Pandey

    2014-08-01

    Full Text Available Intra Uterine Contraception Device (IUCD is the most widely used method of reversible contraception. However complications are known to occur with IUCD. Although uterine perforation is not very rare, but asymptomatic migration into urinary bladder and mesoappendix, is a very rare occurrence. We hereby report two such cases. Two cases of migrated IUCD into urinary bladder and mesoappendix is described here. Both case remained asymptomatic over years and diagnosed incidentally. But IUCD was retrieved in both by surgical means. Owing to possibility of potential complications and medico-legal concerns due to migrated IUCD, it needs to be removed even in asymptomatic cases. [Int J Reprod Contracept Obstet Gynecol 2014; 3(4.000: 1110-1112

  15. En fornemmelse for migration

    DEFF Research Database (Denmark)

    Schütze, Laura Maria

    Afhandlingen undersøger, hvordan sted, museets rolle som aktør og religion er relevante for produktionen af migration på Immigrantmuseet (2012) og i Københavns Museums udstilling At blive københavner (2010). Afhandlingen er baseret på udstillingsanalyse samt interview med relevant museumsfagligt......, anvendes som virkemidler til at nuancere migration og distancere udstillingen fra den offentlige debat om indvandring. Afhandlingen peger på, at produktionen af den nyere danske historie på museum er præget af et fravær af religion. Det skyldes, at de museumsfaglige praksisser og traditioner afspejler en...... identiteter, som vi tager for givet: nationer, byer, kvinder - såvel som migration og religion. Afhandlingen argumenterer følgelig for, at museernes produktion af (materiel) religion er et særdeles relevant, men kun ringe udforsket, genstandsfelt for religionssociologien....

  16. Effects of lichens on uranium migration

    International Nuclear Information System (INIS)

    The lichen Trapelia involuta from uraniferous spoil heaps in Cornwall, England, growing directly on the secondary uranium minerals, metazeunerite and metatorbernite, was examined by field-emission scanning electron microscopy and transmission electron microscopy to assess the effect of Trapelia on uranium migration. We observed metazeunerite, sericite and scorodite as well as unidentified Fe-, Pb/As-, Fe/As-, Al/P-, Pb-bearing minerals concentrated in the lichen exciple and medulla. In addition, metazeunerite also occurred in the epithecium. The chemistries, sizes, and occurrences of the above minerals in the lichen suggest that fixation of U as well as Pb, As, Fe, and Al is dependent on lichen physiological processes. We suggest Trapelia accumulates these elements from groundwater and precipitates the above minerals within specific tissues. Our results indicate that some lichens retard uranium migration by accumulating uranium from groundwater and forming uranium-bearing minerals within their tissues. Copyright (2001) Material Research Society

  17. Migration behaviour of iodine in nuclear fuel

    International Nuclear Information System (INIS)

    A novel out-reactor method has been further developed for investigating the migration behaviour of fission products in UO2 nuclear fuel, which allows the effects of thermal diffusion, radiation damage and local segregation to be independently assessed. Tailored concentration profiles of any desired species are first created in the near-surface region of polished samples by ion implantation. The impact of either thermal annealing or simulated fission is then precisely determined by depth profiling with high-performance secondary ion mass spectrometry (SIMS). Comparison of iodine migration in UO2 wafers that had been ion-implanted to fluences spanning five orders of magnitude has revealed subtle radiation-damage effects and a pronounced concentration dependence for thermal diffusion. At concentrations above ?1016 atoms/cm3 much of the iodine became trapped, likely in microscopic bubbles. True thermal diffusion coefficients for iodine in polycrystalline UO2 have been derived by modelling the low-fluence data. (authors)

  18. Migration behaviour of iodine in nuclear fuel

    International Nuclear Information System (INIS)

    A novel out-reactor method has been further developed for investigating the migration behaviour of fission products in UO2 nuclear fuel, which allows the effects of thermal diffusion. radiation damage and local segregation to be independently assessed. Tailored concentration profiles of any desired species are first created in the near-surface region of polished samples by ion implantation. The impact of either thermal annealing or simulated fission is then precisely determined by depth profiling with high-performance secondary ion mass spectrometry (SIMS). Comparison of iodine migration in U02 wafers that had been ion-implanted to fluences spanning five orders of magnitude has revealed subtle radiation-damage effects and a pronounced concentration dependence for thermal diffusion. At concentrations above ?1016 atoms/cm3 much of the iodine became trapped, likely in microscopic bubbles. True thermal diffusion coefficients for iodine in polycrystalline U02 have been derived by modelling the low-fluence data. (author)

  19. Proceedings of hydrocarbon contaminated soils and groundwater

    International Nuclear Information System (INIS)

    This book reports on hydrogen contaminated soils and groundwater. Topics covered include: perspectives on hydrocarbon contamination; emerging hydrocarbon contamination issues; analytical methodologies and site assessment for hydrocarbon contaminated soils and groundwater; environmental fate and modeling; remedial technologies for hydrocarbon contaminated soils and groundwater; and risk assessment and risk management

  20. Hydrocarbon Leak Detection Sensor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — FTT is proposing the development of a sensor to detect the presence of hydrocarbons in turbopump Inter-Propellant Seals (IPS). The purpose of the IPS is to prevent...

  1. Migrating for a Profession

    DEFF Research Database (Denmark)

    Olwig, Karen Fog

    2015-01-01

    Youths from the Global South migrating for further education often face various forms of discrimination. This Caribbean case study discusses how conditions in the home country can provide a foundation for educational migration that helps the migrants overcome such obstacles and even develop a...... its high quality and downplayed the problems encountered. This positive attitude, it is argued, must be understood in the light of the key ideological role of education, particularly for a profession, as an avenue of social and personal mobility in the late-colonial Caribbean societies and the ways in...... which it enabled these Caribbean women to stake out a new life for themselves....

  2. Unix Application Migration Guide

    CERN Document Server

    Microsoft. Redmond

    2003-01-01

    Drawing on the experience of Microsoft consultants working in the field, as well as external organizations that have migrated from UNIX to Microsoft® Windows®, this guide offers practical, prescriptive guidance on the issues you are likely to face when porting existing UNIX applications to the Windows operating system environment. Senior IT decision makers, network managers, and operations managers will get real-world guidance and best practices on planning and implementation issues to understand the different methods through which migration or co-existence can be accomplished. Also detailing

  3. Migrating for a Profession

    DEFF Research Database (Denmark)

    Olwig, Karen Fog

    2015-01-01

    Youths from the Global South migrating for further education often face various forms of discrimination. This Caribbean case study discusses how conditions in the home country can provide a foundation for educational migration that helps the migrants overcome such obstacles and even develop a...... strong sense of agency and self-empowerment. In the post-WWII period, numerous Caribbean women trained in nursing at British hospitals that have been described as marred by race and gender related inequality and associated forms of exploitation. Yet, the nurses interviewed about this training emphasised...

  4. [Migration, climate and health].

    Science.gov (United States)

    Tellier, Siri; Carballo, Manuel; Calballo, Manuel

    2009-10-26

    Many tentative connections have been postulated between migration and climate. This article points to rural-urban migration, particularly into low elevation urban slums prone to flooding as an issue needing urgent attention by health professionals. It also notes the no-man's land in which environmental refugees find themselves and the consequences this may have. Finally, it points to the urgent need to reform health systems in both developing and developed countries to adapt to rapidly changing disease patterns and to become more responsive to them. PMID:19857400

  5. Aliphatic hydrocarbons of the fungi.

    Science.gov (United States)

    Weete, J. D.

    1972-01-01

    Review of studies of aliphatic hydrocarbons which have been recently detected in the spores of phytopathogenic fungi, and are found to be structurally very similar to the alkanes of higher plants. It appears that the hydrocarbon components of the few mycelial and yeast forms reported resemble the distribution found in bacteria. The occurence and distribution of these compounds in the fungi is discussed. Suggested functional roles of fungal spore alkanes are presented.

  6. Bioassay of polycyclic aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Van Kirk, E.A.

    1980-08-01

    A positive relationship was found between the photodynamic activity of 24 polycyclic aromatic hydrocarbons versus published results on the mutagenicity, carcinogenicity, and initiation of unscheduled DNA synthesis. Metabolic activation of benzo(a)pyrene resulted in detection of increased mutagenesis in Paramecium tetraurelia as found also in the Ames Salmonella assay. The utility of P. tetraurelia as a biological detector of hazardous polycyclic aromatic hydrocarbons is discussed.

  7. Electrochemical decomposition of chlorinated hydrocarbons

    OpenAIRE

    McGee, Gerard Anthony

    1993-01-01

    This work involves the characterisation of the electrochemical decomposition of chlorinated hydrocarbons. A variety of methods were employed involving the use of catalytic reagents to enhance the rate at which chlorinated organic compounds are reduced. The first reagent used was oxygen which was electrochemically reduced to superoxide in nonaqueous solvents. Superoxide is a reactive intermediate and decomposes chlorinated hydrocarbons. However it was found that since the rate of reaction betw...

  8. Hydrocarbon removal with constructed wetlands

    OpenAIRE

    Eke, Paul Emeka

    2008-01-01

    Wetlands have long played a significant role as natural purification systems, and have been effectively used to treat domestic, agricultural and industrial wastewater. However, very little is known about the biochemical processes involved, and the use of constructed treatment wetlands in the removal of petroleum aromatic hydrocarbons from produced and/or processed water. Wastewaters from the oil industry contain aromatic hydrocarbons such as benzene, toluene, ethylbenzene and x...

  9. Electrostatically atomised hydrocarbon sprays

    Energy Technology Data Exchange (ETDEWEB)

    Yule, A.J.; Shrimpton, J.S.; Watkins, A.P.; Balachandran, W.; Hu, D. [UMIST, Manchester (United Kingdom). Thermofluids Division, Dept. of Mechanical Engineering

    1995-07-01

    A burner using an electrostatic method to produce and control a fuel spray is investigated for non-burning sprays. The burner has a charge injection nozzle and the liquid flow rate and charge injection rate are varied using hydrocarbon liquids of differing viscosities, surface tensions and electrical conductivities (kerosene, white spirit and diesel oil). Droplet size distributions are measured and it is shown how the dropsize, spray pattern, breakup mechanism and breakup length depend on the above variables, and in particular on the specific charge achieved in the spray. The data are valuable for validating two computer models under development. One predicts the electric field and flow field inside the nozzle as a function of emitter potential, geometry and flow rate. The other predicts the effect of charge on spray dispersion, with a view to optimizing spray combustion. It is shown that electrostatic disruptive forces can be used to atomize oils at flow rates commensurate with practical combustion systems and that the charge injection technique is particularly suitable for highly resistive liquids. Possible limitations requiring further research include the need to control the wide spray angle, which may provide fuel-air mixtures too lean near the nozzle, and the need to design for maximum charge injection rate, which is thought to be limited by corona breakdown in the gas near the nozzle orifice. 30 refs., 15 figs., 1 tab.

  10. Evaluation of hydrocarbon potential

    Energy Technology Data Exchange (ETDEWEB)

    Cashman, P.H.; Trexler, J.H. Jr. [Univ. of Nevada, Reno, NV (United States)

    1992-09-30

    Task 8 is responsible for assessing the hydrocarbon potential of the Yucca Mountain vincinity. Our main focus is source rock stratigraphy in the NTS area in southern Nevada. (In addition, Trexler continues to work on a parallel study of source rock stratigraphy in the oil-producing region of east central Nevada, but this work is not funded by Task 8.) As a supplement to the stratigraphic studies, we are studying the geometry and kinematics of deformation at NTS, particularly as these pertain to reconstructing Paleozoic stratigraphy and to predicting the nature of the Late Paleozoic rocks under Yucca Mountain. Our stratigraphic studies continue to support the interpretation that rocks mapped as the {open_quotes}Eleana Formation{close_quotes} are in fact parts of two different Mississippian units. We have made significant progress in determining the basin histories of both units. These place important constraints on regional paleogeographic and tectonic reconstructions. In addition to continued work on the Eleana, we plan to look at the overlying Tippipah Limestone. Preliminary TOC and maturation data indicate that this may be another potential source rock.

  11. HYDROCARBONS RESERVES IN VENEZUELA

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Cruz, D.J.

    2007-07-01

    Venezuela is an important player in the energy world, because of its hydrocarbons reserves. The process for calculating oil and associated gas reserves is described bearing in mind that 90% of the gas reserves of Venezuela are associated to oil. Likewise, an analysis is made of the oil reserves figures from 1975 to 2003. Reference is also made to inconsistencies found by international experts and the explanations offered in this respect by the Ministry of Energy and Petroleum (MENPET) and Petroleos de Venezuela (PDVSA) regarding the changes that took place in the 1980s. In turn, Hubbert's Law is explained to determine peak production of conventional oil that a reservoir or field will reach, as well as its relationship with remaining reserves. Emphasis is placed on the interest of the United Nations on this topic. The reserves of associated gas are presented along with their relationship with the different crude oils that are produced and with injected gas, as well as with respect to the possible changes that would take place in the latter if oil reserves are revised. Some recommendations are submitted so that the MENPET starts preparing the pertinent policies ruling reserves. (auth)

  12. Migration scenarii in extrasolar systems

    Directory of Open Access Journals (Sweden)

    Crida A.

    2011-02-01

    Full Text Available In this review talk, I present the theory of type I migration of small mass planets, and its latest developments that open the possibility of outward migration in the inner part of a protoplanetary disk. I also review the type II migration of giant planets, and mention the runaway, type III. Then, we focus on the migration of pairs of planets in resonance. The eccentricity of the planets raise, and possibly their mutual inclination as well. Also, the migration rate can be changed, and directed outward if the outer planet is the lighter. Last, we present a synthetic scenario of migration for the giant planets of our Solar System.

  13. Groundwater recharge as a mechanism to replenish sulfate for natural attenuation of hydrocarbon plumes

    International Nuclear Information System (INIS)

    Intrinsic biodegradation plays a critical role in limiting the lateral migration of groundwater plumes contaminated with petroleum. As such, bioremediation is often considered as a site management and remediation strategy. Various electron acceptors exist within different zones in hydrocarbon plumes. Bacterial sulfate reduction is a dominant terminal electron accepting process in the natural attenuation of hydrocarbons in groundwater. Therefore, the addition of sulfate can enhance the biodegradation of hydrocarbons in groundwater. This paper presented the results of two field studies in southern Alberta that showed evidence that seasonal recharge is a significant mechanism to replenish sulfate as an electron acceptor in dissolved petroleum hydrocarbon plumes in groundwater. The first site was a natural gas well site, while the other was at a natural gas processing plant. BTEX (benzene, toluene, ethylbenzene and xylenes) was the contaminant of primary concern in plumes derived from natural gas condensates at the 2 field sites. The plumes showed evidence of downward migration of sulfate from the unsaturated zone during seasonal groundwater recharge. There was subsequent consumption of the sulfate by microbial reduction, associated with plume biodegradation. High water-soluble sulfate concentrations were found in the vadose zones. These results were in good agreement with results from other studies, but it was suggested that more research is needed to quantify the sulfate replenishment process to identify the relationship between sulfate reduction and hydrocarbon degradation, and to test the supplementation of sulfate. 18 refs., 10 figs

  14. Many Faces of Migrations

    Directory of Open Access Journals (Sweden)

    Milica Antić Gaber

    2013-12-01

    Full Text Available Temporary or permanent, local or international, voluntary or forced, legal or illegal, registered or unregistered migrations of individuals, whole communities or individual groups are an important factor in constructing and modifying (modern societies. The extent of international migrations is truly immense. At the time of the preparation of this publication more than 200 million people have been involved in migrations in a single year according to the United Nations. Furthermore, three times more wish to migrate, mostly from sub-Saharan Africa towards some of the most economically developed areas of the world according to the estimates by the Gallup Institute (Esipova, 2011. Some authors, although aware that it is not a new phenomenon, talk about the era of migration (Castles, Miller, 2009 or the globalization of migration (Friedman, 2004. The global dimensions of migration are definitely influenced also by the increasingly visible features of modern societies like constantly changing conditions, instability, fluidity, uncertainty etc. (Beck, 2009; Bauman, 2002.The extent, direction, type of migrations and their consequences are affected by many social and natural factors in the areas of emigration and immigration. In addition, researchers from many scientific disciplines who study migrations have raised a wide range of research questions (Boyle, 2009, 96, use a variety of methodological approaches and look for different interpretations in various spatial, temporal and contextual frameworks. The migrations are a complex, multi-layered, variable, contextual process that takes place at several levels. Because of this, research on migrations has become an increasingly interdisciplinary field, since the topics and problems are so complex that they cannot be grasped solely and exclusively from the perspective of a single discipline or theory. Therefore, we are witnessing a profusion of different “faces of migration”, which is reflected and at the same time also contributed to by this thematic issue of the journal Ars & Humanitas.While mobility or migration are not new phenomena, as people have moved and migrated throughout the history of mankind, only recently, in the last few decades, has theoretical and research focus on them intensified considerably. In the last two decades a number of research projects, university programs and courses, research institutes, scientific conferences, seminars, magazines, books and other publications, involving research, academia as well as politics and various civil society organizations have emerged. This shows the recent exceptional interest in the issue of migration, both in terms of knowledge of the processes involved, their mapping in the history of mankind, as well as the theoretical development of migration studies and daily management of this politically sensitive issue.Migration affects many entities on many different levels: the individuals, their families and entire communities at the local level in the emigrant societies as well as in the receiving societies. The migration is changing not only the lives of individuals but whole communities and societies, as well as social relations; it is also shifting the cultural patterns and bringing important social transformations (Castles 2010. This of course raises a number of questions, problems and issues ranging from human rights violations to literary achievements. Some of these are addressed by the authors in this thematic issue.The title “Many faces of migration”, connecting contributions in this special issue, is borrowed from the already mentioned Gallup Institute’s report on global migration (Esipova, 2011. The guiding principle in the selection of the contributions has been their diversity, reflected also in the list of disciplines represented by the authors: sociology, geography, ethnology and cultural anthropology, history, art history, modern Mediterranean studies, gender studies and media studies. Such an approach necessarily leads not only to a diverse, but at least seemingly also incompatible, perhaps even opposing views “on a given topic. However, we did not want to silence the voices of “other” disciplines, but within the reviewing procedures actually invited scientists from the fields represented by the contributors to this volume. The wealth of the selected contributions lies therefore not only in their coherence and complementarity, but also in the diversity of views, stories and interpretations.The paper of Zora Žbontar deals with the attitudes towards foreigners in ancient Greece, where the hospitality to strangers was considered so worthy a virtue that everyone was expected to “demonstrate hospitality and protection to any foreigner who has knocked on their door”. The contrast between the hospitality of ancient Greece and the modern emergence of xenophobia and ways of dealing with migration issues in economically developed countries is especially challenging. “In an open gesture of hospitality to strangers the ancient Greeks showed their civilization”.Although the aforementioned research by the United Nations and Gallup Institute support some traditional stereotypes of the main global flows of migrants, and the areas about which the potential migrants “dream”, Bojan Baskar stresses the coexistence of different migratory desires, migration flows and their interpretations. In his paper he specifically focuses on overcoming and relativising stereotypes as well as theories of immobile and non-enterprising (Alpine mountain populations and migrations.The different strategies of the crossing borders adopted by migrant women are studied by Mirjana Morokvasic. She marks them as true social innovators, inventing different ways of transnational life resulting in a bottom-up contribution to the integrative processes across Europe. Some of their innovations go as far as to shift diverse real and symbolic boundaries of belonging to a nation, gender, profession.Elaine Burroughs and Zoë O’Reilly highlight the close relations between the otherwise well-established terminology used in statistics and science to label immigrants in Ireland and elsewhere in EU, and the negative representations of certain types of migrants in politics and the public. The discussion focusses particularly on asylum seekers and illegal immigrants who come from outside the EU. The use of language can quickly become a political means of exclusion, therefore the authors propose the development and use of more considerate and balanced migration terminology.Damir Josipovič proposes a change of the focal point for identifying and interpreting the well-studied migrations in the former Yugoslavia. The author suggests changing the dualistic view of these migrations to an integrated, holistic view. Instead of a simplified understanding of these migrations as either international or domestic, voluntary or forced, he proposes a concept of pseudo-voluntary migrations.Maja Korać-Sanderson's contribution highlights an interesting phenomenon in the shift in the traditional patterns of gender roles. The conclusions are derived from the study of the family life of Chinese traders in transitional Serbia. While many studies suggest that child care in recent decades in immigrant societies is generally performed by immigrants, her study reveals that in Serbia, the Chinese merchants entrust the care of their children mostly to local middle class women. The author finds this switch of roles in the “division of labour” in the child care favourable for both parties involved.Francesco Della Puppa focuses on a specific part of the mosaic of contemporary migrations in the Mediterranean: the Bangladeshi immigrant community in the highly industrialized North East of Italy. The results of his in-depth qualitative study reveal the factors that shape this segment of the Bangladeshi diaspora, the experiences of migrants and the effects of migration on their social and biographical trajectories.John A. Schembri and Maria Attard present a snippet of a more typical Mediterranean migration process - immigration to Malta. The authors highlight the reduction in migration between Malta and the United Kingdom, while there is an increase in immigration to Malta from the rest of Europe and sub-Saharan Africa. Amongst the various impacts of immigration to Malta the extraordinary concentration of immigrant populations is emphasized, since the population density of Malta far exceeds that of nearly all other European countries.Miha Kozorog studies the link between migration and constructing their places of their origin. On the basis of Ardener’s theory the author expresses “remoteness” of the emigratory Slavia Friulana in terms of topology, in relation to other places, rather than in topography. “Remoteness” is formed in relation to the “outside world”, to those who speak of “remote areas” from the privileged centres. The example of an artistic event, which organizers aim “to open a place like this to the outside world”, “to encourage the production of more cosmopolitan place”, shows only the temporary effect of such event on the reduction of the “remoteness”.Jani Kozina presents a study of the basic temporal and spatial characteristics of migration “of people in creative occupations” in Slovenia. The definition of this specific segment of the population and approach to study its migrations are principally based on the work of Richard Florida. The author observes that people with creative occupations in Slovenia are very immobile and in this respect quite similar to other professional groups in Slovenia, but also to the people in creative professions in the Southern and Eastern Europe, which are considered to be among the least mobile in Europe. Detailed analyses show that the people in creative occupations from the more developed regions generally migrate more intensely and are also more willing to relocate.Mojca Pajnik and Veronika Bajt study the experiences of migrant women with the access to the labour market in Slovenia. Existing laws and policies push the migrants into a position where, if they want to get to work, have to accept less demanding work. In doing so, the migrant women are targets of stereotyped reactions and practices of discrimination on the basis of sex, age, attributed ethnic and religious affiliation, or some other circumstances, particularly the fact of being migrants. At the same time the latter results in the absence of any protection from the state.Migration studies often assume that the target countries are “modern” and countries of origin “traditional”. Anıl Al- Rebholz argues that such a dichotomous conceptualization of modern and traditional further promotes stereotypical, essentialist and homogenizing images of Muslim women in the “western world”. On the basis of biographical narratives of young Kurdish and Moroccan women as well as the relationships between mothers and daughters, the author illustrates a variety of strategies of empowerment of young women in the context of transnational migration.A specific face of migration is highlighted in the text of Svenka Savić, namely the face of artistic migration between Slovenia and Serbia after the Second World War. The author explains how more than thirty artists from Slovenia, with their pioneering work in three ensembles (opera, ballet and theatre, significantly contributed to the development of the performing arts in the Serbian National Theatre in Novi Sad.We believe that in the present thematic issue we have succeeded in capturing an important part of the modern European research dynamic in the field of migration. In addition to well-known scholars in this field several young authors at the beginning their research careers have been shortlisted for the publication. We are glad of their success as it bodes a vibrancy of this research area in the future. At the same time, we were pleased to receive responses to the invitation from representatives of so many disciplines, and that the number of papers received significantly exceeded the maximum volume of the journal. Recognising and understanding of the many faces of migration are important steps towards the comprehensive knowledge needed to successfully meet the challenges of migration issues today and even more so in the future. It is therefore of utmost importance that researchers find ways of transferring their academic knowledge into practice – to all levels of education, the media, the wider public and, of course, the decision makers in local, national and international institutions. The call also applies to all authors in this issue of the journal.

  15. Brain Migration Revisited

    Science.gov (United States)

    Vinokur, Annie

    2006-01-01

    The "brain drain/brain gain" debate has been going on for the past 40 years, with irresolvable theoretical disputes and unenforceable policy recommendations that economists commonly ascribe to the lack of reliable empirical data. The recent report of the World Bank, "International migration, remittances and the brain drain", documents the…

  16. International Migration of Couples

    DEFF Research Database (Denmark)

    Munk, Martin D.; Junge, Martin

    2015-01-01

    We analyze emigration and return decisions of Danish couples. Our main questions are how emigration and return migration decisions depend on education, earnings, and the number and age of children. We use register data on full population from 1982 to 2006, focusing on opposite-gender couples in which the female is aged 23 to 37, and the male 25 to 39. We find that power couples in which both are highly educated are most likely to emigrate, but also most likely to return. Couples in which only the male is highly educated are more than twice as likely to emigrate as if only the female is highly edu-cated. Couples in which neither partner is highly educated are least likely to emigrate, but also have lowest return migration rates. This suggests that migration as brain circu-lation is most pronounced among the highly-educated. The probability of emigration is increasing in male earnings, but does not depend much on female earnings. Having children reduces the likelihood of emigration and the more so the older children are. Surprisingly, the return rates do not depend much on the number of children. Overall, our findings suggest that family migration patterns are still surprisingly traditional, re-sponding more to the male's job opportunities and education.

  17. Selective Migration--Again.

    Science.gov (United States)

    Kamin, Leon J.

    1980-01-01

    Wolff has recently reinterpreted the data of Lee to indicate that Black migration from the south to Philadelphia had been selective in an IQ-relevant manner. However, Wolff's deduction from Lee's data is shown to depend entirely upon an assumption about cumulative IQ deficit in southern Black children. (Author/CTM)

  18. Migration pathways in soils

    International Nuclear Information System (INIS)

    This study looked at diffusive migration through three types of deformation; the projectile pathways, hydraulic fractures of the sediments and faults, and was divided into three experimental areas: autoradiography, the determination of diffusion coefficients and electron microscopy of model projectile pathways in clay. For the autoradiography, unstressed samples were exposed to two separate isotopes, Pm-147 (a possible model for Am behaviour) and the poorly sorbed iodide-125. The results indicated that there was no enhanced migration through deformed kaolin samples nor through fractured Great Meteor East (GME) sediment, although some was evident through the projectile pathways in GME and possibly through the GME sheared samples. The scanning electron microscopy of projectile pathways in clay showed that emplacement of a projectile appeared to have no effect on the orientation of particles at distances greater than two projectile radii from the centre of a projectile pathway. It showed that the particles were not simply aligned with the direction of motion of the projectile but that, the closer to the surface of a particular pathway, the closer the particles lay to their original orientation. This finding was of interest from two points of view: i) the ease of migration of a pollutant along the pathway, and ii) possible mechanisms of hole closure. It was concluded that, provided that there is no advective migration, the transport of radionuclides through sediments containing these defects would not be significantly more rapid than in undeformed sediments. (author)

  19. Practical Data Migration

    CERN Document Server

    Morris, Johny

    2012-01-01

    This book is for executives and practitioners tasked with the movement of data from old systems to a new repository. It uses a series of steps guaranteed to get the reader from an empty new system to one that is working and backed by the user population. Using this proven methodology will vastly increase the chances of a successful migration.

  20. Migration and Africa

    DEFF Research Database (Denmark)

    Zoppi, Marco

    2014-01-01

    European powers imposed the nation-state on Africa through colonialism. But even after African independencies, mainstream discourses and government policies have amplified the idea that sedentariness and the state are the only acceptable mode of modernity. Migration is portrayed as a menace to the...

  1. Digitizing migration heritage

    DEFF Research Database (Denmark)

    Marselis, Randi

    2011-01-01

    Museums are increasingly digitizing their collections and making them available to the public on-line. Creating such digital resources may become means for social inclusion. For museums that acknowledge migration history and cultures of ethnic minority groups as important subjects in multiethnic...

  2. Migrating the Light

    DEFF Research Database (Denmark)

    Sørensen, Bent

    The migration of Blaga’s universalist, even centralist poems from Romanian of the first third of the 20th C. into American of the first fifth of the 21st C. illustrates the uses of Pierre Joris’s nomadic methods. My translations of Blaga read well for a teenage audience whose only exposure to...

  3. Fall armyworm migration patterns.

    Science.gov (United States)

    Fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), infestations in most of North America arise from annual migrations of populations that overwinter in southern Texas and Florida. Cytochrome Oxidase I haplotype profiles within the fall armyworm corn-strain, the subgroup tha...

  4. Radionuclide migration in groundwater

    International Nuclear Information System (INIS)

    The migration rates and mechanisms of a large suite of radionuclides in groundwater created by the disposal of low-level aqueous effluents from the Hanford N-Reactor are being characterized. These studies are developing information which can be applied to understanding and predicting the movement of radionuclides in shallow-land burial sites which may become saturated with groundwater. The movement of the various radionuclides in groundwater at the N-Reactor disposal site is being investigated as a function of their physicochemical forms. Those radionuclides most readily migrating include tritium and anionic species of 131133I, 60Co, 103106Ru, 122124125Sb, /sup 99m,99/Tc, and 99Mo. Also migrating are traces of 238239240Pu in an oxidized (V or VI) anionic form(s). Various parameters affecting the physicochemical speciation of the radionuclides, including the major and trace ions, organic constitutents, colloidal materials, and soil chemistry are being characterized to determine their relative roles in the migration processes. the data generated in this study will be extremely valuable in formulating guidelines for the operation of existing low-level waste disposal sites, in determining what long-term surveillance and maintenance needs will be required, and in determining essential requirements for remedial action. 4 tables

  5. Migration mechanisms of radionuclides from a clay repository toward adjacent aquifers and the surface

    International Nuclear Information System (INIS)

    This article is a critical review of the current understanding of migration processes of solutes in clay. The major migration mechanisms are examined: advection through compaction, thermal convection, migration by hydrocarbon expulsion, gravitational flow, osmosis, molecular diffusion, hydrodynamic dispersion. Examples are taken from the Callovo-Oxfordian clays of the Paris basin in the Meuse/Haute Marne area, near Bure, where France is studying the feasibility of a potential nuclear waste disposal facility. Recent work on the helium distribution in the aquifers of the Paris Basin confirms the importance of molecular diffusion for solute transport in clays. Migration in aquifers is also described, and the major causes of uncertainties for solute migration are discussed. (authors)

  6. Polycyclic Aromatic Hydrocarbons

    Science.gov (United States)

    Salama, Farid

    2010-01-01

    Carbonaceous materials play an important role in space. Polycyclic Aromatic Hydrocarbons (PAHs) are a ubiquitous component of the carbonaceous materials. PAHs are the best-known candidates to account for the IR emission bands. They are also thought to be among the carriers of the diffuse interstellar absorption bands (DIBs). PAH ionization states reflect the ionization balance of the medium while PAH size, composition, and structure reflect the energetic and chemical history of the medium. A major challenge is to reproduce in the laboratory the physical conditions that exist in the emission and absorption interstellar zones. The harsh physical conditions of the ISM -low temperature, collisionless, strong UV radiation fields- are simulated in the laboratory by associating a molecular beam with an ionizing discharge to generate a cold plasma expansion. PAH ions and radicals are formed from the neutral precursors in an isolated environment at low temperature and probed with high-sensitivity cavity ringdown spectroscopy in the NUV-NIR range. Carbon nanoparticles are also formed during the short residence time of the precursors in the plasma and are characterized with time-offlight mass spectrometry. These experiments provide unique information on the spectra of large carbonaceous molecules and ions in the gas phase that can now be directly compared to interstellar and circumstellar observations (IR emission bands, DIBs, extinction curve). These findings also hold great potential for understanding the formation process of interstellar carbonaceous grains. We will review recent progress in the experimental and theoretical studies of PAHs, compare the laboratory data with astronomical observations and discuss the global implications.

  7. Globalization, Migration and Development

    Directory of Open Access Journals (Sweden)

    George, Susan

    2002-01-01

    Full Text Available EnglishMigration may become the most important branch of demography in the earlydecades of the new millennium in a rapidly globalizing world. This paper discusses the causes, costsand benefits of international migration to countries of the South and North, and key issues of commonconcern. International migration is as old as national boundaries, though its nature, volume,direction, causes and consequences have changed. The causes of migration are rooted in the rate ofpopulation growth and the proportion of youth in the population, their education and training,employment opportunities, income differentials in society, communication and transportationfacilities, political freedom and human rights and level of urbanization. Migration benefits the Souththrough remittances of migrants, improves the economic welfare of the population (particularly womenof South countries generally, increases investment, and leads to structural changes in the economy.However, emigration from the South has costs too, be they social or caused by factors such as braindrain. The North also benefits by migration through enhancement of economic growth, development ofnatural resources, improved employment prospects, social development and through exposure toimmigrants' new cultures and lifestyles. Migration also has costs to the North such as of immigrantintegration, a certain amount of destabilization of the economy, illegal immigration, and socialproblems of discrimination and exploitation. Issues common to both North and South include impact onprivate investment, trade, international cooperation, and sustainable development. Both North andSouth face a dilemma in seeking an appropriate balance between importing South's labour or itsproducts and exporting capital and technology from the North.FrenchLa migration est sans doute devenue la partie la plus importante de la démographie des premières décennies du nouveau millénaire dans un monde qui change rapidement. Ce document porte sur les causes, les coûts et les avantages de la migration internationale vers les pays du Sud et du Nord ainsi que sur les grandes préoccupations communes. La migration internationale existe depuis l'avènement des frontières nationales, bien que sa nature, son volume, sa direction ainsi que ses causes et conséquences aient changé. Les causes de la migration trouvent leur origine dans le taux de croissance d'une population, sa proportion de jeunes, leur niveau d'éducation et de formation, les occasions d'emploi, les écarts de revenu dans la société, les systèmes de communication et de transport, la liberté politique, les droits de la personne et le niveau d'urbanisation. La migration profite au Sud parce que les migrants envoient de l'argent, améliorant généralement le bien-être économique de la population (surtout celui des femmes des pays du Sud, augmentant les investissements et donne lieu à des changements structuraux de l'économie. Cependant, l'émigration du Sud a tout de même un prix, que ce soit social ou causé par des facteurs tels que l'exode des cerveaux. Le Nord profite aussi de la migration grâce à une meilleure croissance économique, l'exploitation de richesses naturelles, de meilleures possibilités d'emploi et le développement social par l'exposition aux nouvelles cultures et styles de vie des immigrants. La migration a aussi un prix pour le Nord tel que l'intégration des immigrants, une certaine déstabilisation de l'économie, l'immigration illégale ainsi que les problèmes sociaux relatifs à la discrimination et à l'exploitation. Les préoccupations communes au Sud et au Nord incluent les incidences sur les investissements privés, le commerce, la coopération internationale et le développement durable. Autant le Nord que le Sud doivent composer avec le dilemme de trouver l'équilibre entre l'importation de la main-d'œuvre du Sud.

  8. Study of liquid hydrocarbons subjected to ionizing radiations

    International Nuclear Information System (INIS)

    This work is a study of liquid hydrocarbons (especially alkanes and cycloalkanes), ionized and excited by low L.E.T. high energy radiation. An analysis of radiolytical products shows a definite correlation between radiochemical yields and bond energies. The study of the influence of scavengers has been carried out and the methods for the determination of ? parameters are discussed. Ionic recombination has been fully investigated: theoretical studies, based on a phenomenological model, on primary and (in presence of solute) secondary charge recombination have been performed. Secondary species were observed by use of kinetic optical absorption spectrophotometry. A good agreement with theory is obtained only when the electron scavenging before thermalization is negligible. Electron mobility in hydrocarbons has been measured and the electron scavenging rate constants have been determined using the pulse conductivity technique. Conformational analysis calculations show a correlation between the electron mobility and the electronic structure. The rate of formation of a radiolytic product and the rate of decay of its precursor have been studied for solutions of hydrocarbons and electron scavengers

  9. The International Organization for Migration in Global Migration Governance

    OpenAIRE

    Poulsen, Sofie Havn; Andersen, Lise

    2011-01-01

    This project focuses on the IOM, the notion of global governance of migration and the interaction between these two. The point of departure has been an attempt to grasp the current global approach to migration and comprehend whether, or to what degree, there is governance of migration issues taking place at a global level.

  10. Experimental investigation of hydrocarbon formation and transformation under Earth´s upper mantle conditions

    OpenAIRE

    Kolesnikov, Anton

    2010-01-01

    The theory of the abyssal abiotic petroleum origin considers oil and natural gas to begenerated in the Earth’s upper mantle. Hydrocarbons migrate further through the deep faults into the Earth’s crust, where they can form oil and gas deposits in any kind of rock in any kind of structural position. Until recently one of the main obstacles for further development of this theory has been the lack of the data covering processes of generation and transformations of hydrocarbons. Experimental data,...

  11. Radionuclide migration studies in soil

    International Nuclear Information System (INIS)

    In this work a brief description about retention and migration parameters of radionuclides in soil, including main methods to determine the distribution coefficient (K) are given. Some of several factors that can act on the migration are also mentioned. (author)

  12. The Analysis of International Migration towards Economic Growth

    Directory of Open Access Journals (Sweden)

    Ferdous Alam

    2011-01-01

    Full Text Available Problem statement: This study discusses the analysis of international migration towards economic growth in Bangladesh. International migration refers to the cross-border movement of people from a mother country to a location outside that mother country, with the purpose of taking up higher income employment, better living conditions, higher education get access to civic amenities and conducting a daily existence there for an extended period of time. The exports of labor, human capital, play a major role to minimize the poverty level in Bangladesh. In the last four decades, Bangladesh exports the huge number of labors abroad for economic growth through remittances. Remittances affect poverty eradication most directly by increasing the income of households which have a family member working abroad. Because income from remittances is usually larger than that which could have been earned by migrants they stayed at home. Approach: The aim of this study is to highlight the policy implications for the maximization of international migration and the analysis of economic growth in Bangladesh. The data for analysis is perceived from the secondary sources. The significant manipulations for acquired data are migration of employment and remittances for economic growth in Bangladesh. Results: Migration contributed for the development of macro and micro level in Bangladesh. Conclusion: There would be potential benefits to world's poor if more international attention were focused on integrating migration policy to within the larger global dialogue economic development and poverty reduction. Strong institutions and good policies will enhance the benefits of human capital migration for Bangladesh.

  13. Isolation and characterization of ancient hydrocarbon biomarkers from crystalline minerals

    Science.gov (United States)

    Summons, R. E.; Carrasquillo, A.; Hallmann, C.; Sherman, L. S.; Waldbauer, J. R.

    2008-12-01

    Hydrocarbon biomarker analysis is conventionally conducted on bitumen (soluble fossilized organic matter) extracted from sedimentary rocks using organic solvents. Biomarkers can also be generated by pyrolysis of kerogen (insoluble organic matter) in the same rocks. These approaches have met with much success where the organic matter has not seen significant levels of thermal metamorphism but more limited success when applied to thermally mature Archean rocks. Biomarkers have also been isolated from fluid inclusions of crystalline minerals and this approach has found wide application in petroleum exploration because of the capability of minerals that form crystals in reservoir rocks to trap organics from different episodes of fluid migration. Lastly, biogenic crystalline minerals are well known to trap organics including amino acids, fatty acids or hydrocarbons from those organisms that laid down the minerals. In fact, recent observations suggest that hydrocarbon biomarkers can be abundantly preserved in crystalline minerals where they may be protected over long periods of time and also distinguished from more recent generations of organics from endolithic organisms (modern) or anthropogenic (fossil hydrocarbon) contaminants. Here we report analyses of biomarker lipids trapped in fluid inclusions or otherwise having a "tight association" with the minerals in sedimentary rocks from Neoarchean and Paleoproterozoic successions in Australia and Southern Africa. In particular, cores recovered from the Agouron Griqualand Drilling Project contain over 2500m of well-preserved late Archean Transvaal Supergroup sediments, dating from ca. 2.67 to 2.46Ga. Bitumen extracts of samples from these strata were obtained using clean drilling, sampling and handling protocols and without overprinting with contaminant hydrocarbons. Dissolution of the mineral matrix of extracted sediments, followed by another solvent extraction, yielded a second bitumen that comprised hydrocarbons that had been, somehow, enclosed within or more tightly bound to clays or carbonates. Subtle and consistent compositional differences between the freely-extractable and tightly-bound hydrocarbons provide further evidence for their syngenetic nature. The research has further applicability to biomarker studies of Early Earth materials, returned planetary samples as well as robotic analyses on flight missions. On Mars, for example, organics trapped within crystals of evaporate minerals would be protected, to a large degree, from the deleterious effects of ionizing radiation and strong oxidants that are prevalent on Mars surface. eaps.mit.edu/geobiology/

  14. CHARACTERISTICS OF MIGRATION IN ROMANIA

    Directory of Open Access Journals (Sweden)

    Daniela D?N?CIC?

    2010-06-01

    Full Text Available The aim of this research is to study the patterns of migration in Romania. Labor migration in Romania has seen major growth after 1989. Permanent migration rapidly increased in the early years after the revolution, decreasing rapidly thereafter, due to difficulties of obtaining long term residence and work permit in the host countries. However, temporary migration has been found to evolve very dynamically, requiring economic analysis of potential externalities, whether positive or the negative of this phenomenon.

  15. The dynamics of mass migration

    OpenAIRE

    Massey, Douglas S.; Zenteno, Rene M.

    1999-01-01

    We specify a set of equations defining a dynamic model of international migration and estimate its parameters by using data specially collected in Mexico. We then used it to project the a hypothetical Mexican community population forward in time. Beginning with a stable population of 10,000 people, we project ahead 50 years under three different assumptions: no international migration; constant probabilities of in- and out-migration, and dynamic schedules of out- and in-migration that change ...

  16. Experimental glomerulonephritis induced by hydrocarbon exposure: A systematic review

    Directory of Open Access Journals (Sweden)

    Ravnskov Uffe

    2005-12-01

    Full Text Available Abstract Background Much epidemiological evidence suggests that hydrocarbon exposure may induce glomerulonephritis and worsen its course in many patients. The mechanisms are unknown, however, no specific microscopic pattern has been identified, and it has also been argued that hydrocarbon exposure causes tubular damage mainly. Studying experimental animals may best answer these questions, and as no systematic review of glomerulonephritis produced experimentally by hydrocarbon exposure has been performed previously, I found it relevant to search for and analyse such studies. Methods Animal experiments having mimicked human glomerulonephritis by hydrocarbon exposure were sought on Medline and Toxnet Results Twenty-six experiments using thirteen different hydrocarbons were identified. Several human subtypes were observed including IgA nephritis, mesangial, proliferative and extracapillary glomerulonephritis, focal and focal-segmental sclerosis, minimal change nephropathy, anti-GBM and anti-TBM nephritis, and glomerulonephritis associated with peiarteritis nodosa. Glomerular proteinuria was seen in 10/12 experiments that included urine analyses, and renal failure in 5/8 experiments that included measurements of glomerular function. All experiments resulted in various degrees of tubular damage as well. In most studies, where the animals were examined at different times during or after the exposure, the renal microscopic and functional changes were seen immediately, whereas deposits of complement and immunoglobulins appeared late in the course, if at all. Conclusion These experiments are in accord with epidemiological evidence that hydrocarbon exposure may cause glomerulonephritis and worsen renal function. Probable mechanisms include an induction of autologous antibodies and a disturbance of normal immunological functions. Also, tubular damage may increase postglomerular resistance, resulting in a glomerular deposition of macromolecules. In most models a causal role of glomerular immune complex formation was unlikely, but may rather have been a secondary phenomenon. As most glomerulonephritis subgroups were seen and as some of the hydrocarbons produced more than one subgroup, the microscopic findings in a patient cannot be used as a clue to the causation of his disease. By the same reason, the lack of a specific histological pattern in patients with glomerulonephritis assumed to have been caused by hydrocarbon exposure is not contradictive.

  17. Diesel-related hydrocarbons can dominate gas phase reactive carbon in megacities

    Directory of Open Access Journals (Sweden)

    R. E. Dunmore

    2015-09-01

    Full Text Available Hydrocarbons are key precursors to two priority air pollutants, ozone and particulate matter. Those with two to seven carbons have historically been straightforward to observe and have been successfully reduced in many developed cities through air quality policy interventions. Longer chain hydrocarbons released from diesel vehicles are not considered explicitly as part of air quality strategies and there are few direct measurements of their gaseous abundance in the atmosphere. This study describes the chemically comprehensive and continuous measurements of organic compounds in a developed megacity (London, which demonstrate that on a seasonal median basis, diesel-related hydrocarbons represent only 20–30 % of the total hydrocarbon mixing ratio but comprise more than 50 % of the atmospheric hydrocarbon mass and are a dominant local source of secondary organic aerosols. This study shows for the first time that 60 % of the winter primary hydrocarbon hydroxyl radical reactivity is from diesel-related hydrocarbons and using the maximum incremental reactivity scale, we predict that they contribute up to 50 % of the ozone production potential in London. Comparing real-world urban composition with regulatory emissions inventories in the UK and US highlights a previously unaccounted for, but very significant, under-reporting of diesel-related hydrocarbons; an underestimation of a factor ~4 for C9 species rising to a factor of over 70 for C12 during winter. These observations show that hydrocarbons from diesel vehicles can dominate gas phase reactive carbon in cities with high diesel fleet fractions. Future control of urban particulate matter and ozone in such locations requires a shift in policy focus onto gas phase hydrocarbons released from diesels as this vehicle type continues to displace gasoline world-wide.

  18. Diesel-related hydrocarbons can dominate gas phase reactive carbon in megacities

    Directory of Open Access Journals (Sweden)

    R. E. Dunmore

    2015-03-01

    Full Text Available Hydrocarbons are key precursors to two priority air pollutants, ozone and particulate matter. Those with two to seven carbons have historically been straightforward to observe and have been successfully reduced in many developed cities through air quality policy interventions. Longer chain hydrocarbons released from diesel vehicles are not considered explicitly as part of air quality strategies and there are few direct measurements of their gaseous abundance in the atmosphere. This study describes the chemically comprehensive and continuous measurements of organic compounds in a developed megacity (London, which demonstrate that on a seasonal median basis, diesel-related hydrocarbons represent only 20–30% of the total hydrocarbon mixing ratio but comprise more than 50% of the atmospheric hydrocarbon mass and are a dominant local source of secondary organic aerosols. This study shows for the first time that, 60% of the winter primary hydrocarbon hydroxyl radical reactivity is from diesel-related hydrocarbons and using the maximum incremental reactivity scale, we predict that they contribute up to 50% of the ozone production potential in London. Comparing real-world urban composition with regulatory emissions inventories in the UK and US highlights a previously unaccounted for but, very significant under-reporting of diesel related hydrocarbons; an underestimation of a factor ~ 4 for C9 species rising to a factor of over 70 for C12 during winter. These observations show that hydrocarbons from diesel vehicles can dominate gas phase reactive carbon in cities with high diesel fleet fractions. Future control of urban particulate matter and ozone in such locations requires a shift in policy focus onto gas phase hydrocarbons released from diesels as this vehicle type continues to displace gasoline world-wide.

  19. Diesel-related hydrocarbons can dominate gas phase reactive carbon in megacities

    Science.gov (United States)

    Dunmore, R. E.; Hopkins, J. R.; Lidster, R. T.; Lee, J. D.; Evans, M. J.; Rickard, A. R.; Lewis, A. C.; Hamilton, J. F.

    2015-09-01

    Hydrocarbons are key precursors to two priority air pollutants, ozone and particulate matter. Those with two to seven carbons have historically been straightforward to observe and have been successfully reduced in many developed cities through air quality policy interventions. Longer chain hydrocarbons released from diesel vehicles are not considered explicitly as part of air quality strategies and there are few direct measurements of their gaseous abundance in the atmosphere. This study describes the chemically comprehensive and continuous measurements of organic compounds in a developed megacity (London), which demonstrate that on a seasonal median basis, diesel-related hydrocarbons represent only 20-30 % of the total hydrocarbon mixing ratio but comprise more than 50 % of the atmospheric hydrocarbon mass and are a dominant local source of secondary organic aerosols. This study shows for the first time that 60 % of the winter primary hydrocarbon hydroxyl radical reactivity is from diesel-related hydrocarbons and using the maximum incremental reactivity scale, we predict that they contribute up to 50 % of the ozone production potential in London. Comparing real-world urban composition with regulatory emissions inventories in the UK and US highlights a previously unaccounted for, but very significant, under-reporting of diesel-related hydrocarbons; an underestimation of a factor ~4 for C9 species rising to a factor of over 70 for C12 during winter. These observations show that hydrocarbons from diesel vehicles can dominate gas phase reactive carbon in cities with high diesel fleet fractions. Future control of urban particulate matter and ozone in such locations requires a shift in policy focus onto gas phase hydrocarbons released from diesels as this vehicle type continues to displace gasoline world-wide.

  20. FACTORS AFFECTING INTERNATIONAL LABOR MIGRATION

    Directory of Open Access Journals (Sweden)

    ?.?. ???????

    2012-03-01

    Full Text Available  The article reviews the evolution of the main theories that explain the labor migration system impacts on international labor migration are shown. Particular attention is paid to the analysis of external labor migration factors in Ukraine based on the use of the basic tenets of the "push and pull factors" theory.

  1. Dispersal and migration

    Directory of Open Access Journals (Sweden)

    Schwarz, C.

    2004-06-01

    Full Text Available Ringing of birds unveiled many aspects of avian migration and dispersal movements. However, there is even much more to be explored by the use of ringing and other marks. Dispersal is crucial in understanding the initial phase of migration in migrating birds as it is to understand patterns and processes of distribution and gene flow. So far, the analysis of migration was largely based on analysing spatial and temporal patters of recoveries of ringed birds. However, there are considerable biases and pitfalls in using recoveries due to spatial and temporal variation in reporting probabilities. Novel methods are required for future studies separating the confounding effects of spatial and temporal heterogeneity of recovery data and heterogeneity of the landscape as well. These novel approaches should aim a more intensive and novel use of the existing recovery data by taking advantage of, for instance, dynamic and multistate modeling, should elaborate schemes for future studies, and should also include other marks that allow a more rapid data collection, like telemetry, geolocation and global positioning systems, and chemical and molecular markers. The latter appear to be very useful in the delineating origin of birds and connectivity between breeding and non–breeding grounds. Many studies of migration are purely descriptive. However, King and Brooks (King & Brooks, 2004 examine if movement patterns of dolphins change after the introduction of a gillnet ban. Bayesian methods are an interesting approach to this problem as they provide a meaningful measure of the probability that such a change occurred rather than simple yes/no response that is often the result of classical statistical methods. However, the key difficulty of a general implementation of Bayesian methods is the complexity of the modelling —there is no general userfriendly package that is easily accessible to most scientists. Drake and Alisauskas (Drake & Alisauskas, 2004 examine the philopatric movement of geese using a classic multi–state design. Previous studies of philopaty often rely upon simple return rates —however, good mark–recapture studies do not need to assume equal detection probabilities in space and time. This is likely the most important contribution of multi–state modelling to the study of movement. As with many of these studies, the most pressing problem in the analysis is the explosion in the number of parameters and the need to choose parsimonious modelss to get good precision. Drake and Alisauska demonstrate that model choice still remains an art with a great deal of biological insight being very helpful in the task. There is still plenty of scope for novel methods to study migration. Traditionally, there has been a clear cut distinction between birds being labelled as “migrant” or “resident” on the basis of field observations and qualitative interpretations of patterns of ring–recoveries. However, there are intermediate species where only part of the population migrates (partial migrants or where different components of the population migrate to different extents (differential migrants. Siriwardena, Wernham and Baillie (Siriwardena et al., 2004 develop a novel method that produces a quantitative index of migratory tendency. The method uses distributions of ringing–to–recovery distances to classify individual species’ patterns of movement relative to those of other species. The areas between species’ cumulative distance distributions are used with multi–dimensional scaling to produce a similarity map among species. This map can be used to investigate the factors that affect the migratory strategies that species adopt, such as body size, territoriality and distribution, and in studies of their consequences for demographic parameters such as annual survival and the timing of breeding. The key assumption of the method is the similar recovery effort of species over space and time. It would be interesting to overlay maps of effort to try and remove any induced artefacts in the data. Differences in

  2. Hydrocarbons as markers for identifying postirradiated peanuts

    International Nuclear Information System (INIS)

    Hydrocarbons produced by ?-radiation of peanuts were analyzed to determine the relationship between irradiation and production of hydrocarbons, and the use of hydrocarbons as markers for identifying postirradiated peanuts. Hydrocarbons in peanuts were determined by a sequential procedure of lipid extraction by hexane, Florisil column chromatography, and gas chromatography. Hydrocarbons C17:1, C16:2, C17:2, and C16:3 were easily detected in peanuts irradiated at 0.5 kGy or higher, but not in unirradiated ones. The hydrocarbons were minimally changed by roasting the irradiated peanuts and were not detected in unirradiated roasted peanuts

  3. Functorial Data Migration

    CERN Document Server

    Spivak, David I

    2010-01-01

    In this paper we present a simple database definition language: that of categories and functors. A database schema is a category and a state is a set-valued functor. We show that morphisms of schemas induce three "data migration functors" that translate states from one schema to the other in canonical ways. Database states form a boolean topos of which the classical "relational algebra" is a fragment. These ideas thus create a new denotational semantics for database theory.

  4. Functorial Data Migration

    OpenAIRE

    Spivak, David I.

    2010-01-01

    In this paper we present a simple database definition language: that of categories and functors. A database schema is a small category and an instance is a set-valued functor on it. We show that morphisms of schemas induce three "data migration functors", which translate instances from one schema to the other in canonical ways. These functors parameterize projections, unions, and joins over all tables simultaneously and can be used in place of conjunctive and disjunctive que...

  5. Customer channel migration

    OpenAIRE

    Böhm, Martin

    2006-01-01

    Customer Channel Migration deals with the active management of a customer's channel usage behavior with the aim to increase her profitability and lifetime. Hence, the dissertation answers two distict questions: on one hand, it investigates the impact of channel use on a customer's profitability and lifetime. On the other hand, it is researched how a customer's channel usage behavior can be influenced and managed. The cumulative dissertation consists of five articles: the first article describ...

  6. Education, unemployment and migration

    OpenAIRE

    Eggert, Wolfgang; Krieger, Tim; Meier, Volker

    2009-01-01

    This paper studies a two-region model in which unemployment, education decisions and interregional migration are endogenous. The poorer region exhibits both lower wages and higher unemployment rates, and migrants to the richer region are disproportionally skilled. The brain drain from the poor to the rich region is accompanied by stronger incentives to acquire skills even for immobile workers. Regional shocks tend to affect both regions in a symmetric fashion, and skilled-biased technological...

  7. Migration of uranium

    International Nuclear Information System (INIS)

    Uranium migration is treated as a process leading to mobilization and concentration of uranium in ore deposits. During the formation of global zonation, uranium migration contributed to the enrichment of this radioactive metal in the Earth's crust. The process of upper mantle and crust fractionation and differentiation is the first cycle of the mobilization process which led to uranium enrichment in rocks in some areas of the upper Earth's crust that could be considered as the primordial uranium provinces. Uranium migration is related to the structural history of sial Earth's crust and sial magmatism. During orogeny conditions could be created for development of progressive metamorphism and for magma generation. The latter is the best process for uranium mobilization. The effectiveness of this process depends on the composition of the primordial rocks and the intensity of the process. The importance of the magmatism for uranium mobilization is due to the magmatic differentiation. Selectively mobilized felsitic parts of the rocks migrate and form felsitic magmatic portions, which mobilize uranium. Solutions are the best uranium mobilization agents. Their generation starts with water separation from local permeable reservoirs and finishes with water dissociation from minerals during their dehydration. Such solutions could be endogenous or exogenous, depending on the igneous or sedimentary rocks which have been deformed. Some of the solutions can have mixed origin, if deformed magmatic rocks contain exogenous water in pores and cracks and endogenous water in minerals. The mobilizing ability of the solutions depends on their energy, which could derive from their chemical compositions and from physical conditions of the geological environment. The movement of the mineralized solutions can be due to steam pressure and the pressure difference between the starting and the final point of the juvenile solutions, gravity for meteoric waters, convection in geoconvection cells, and water pressure in pressured hydrogeological systems. All these types of solution movement are considered, with emphasis on the more common ones. (author). 11 refs, 5 figs

  8. Halting Planetary Migration

    OpenAIRE

    Lecar, M.; Sasselov, D. D.

    1999-01-01

    When Jupiter's Roche Lobe radius exceeded the scale height of the protoplanetary disk, Jupiter opened a gap in the disk. When the gap was wide enough, tidal torques from the disk interior and exterior to Jupiter were suppressed and migration continued on the accretion time scale. In the 'minimum solar nebula' about two Jupiter masses of gas remained between Jupiter and Saturn and about five Jupiter masses between Jupiter and Uranus. Unless all but a Jupiter mass of the outer disk was removed,...

  9. International labour migration

    OpenAIRE

    Salt, John; Clarke, James; Wanner, Philippe ( Laboratoire de démographie et d'études familiales, Université de Genève, Switzerland )

    2004-01-01

    Le présent rapport décrit les grandes caractéristiques des migrations de la main-d’œuvre en Europe et les tendances observées ces dernières années. Il s’intéresse davantage aux travailleurs étrangers engagés dans un processus migratoire qu’aux populations immigrées déjà installées dans le pays d’accueil. Il examine les concepts et les définitions entourant la notion de travailleur migrant, présente brièvement les types et les sources de données, puis étudie les caractéristiques et les tendanc...

  10. Erosion, Contamination, and Migration

    International Nuclear Information System (INIS)

    This paper will summarize studies of carbon impurity sources, contamination, and migration developed through JET methane gas injection experiments. These studies were analyzed using the 2D SOL code EDGE2D/NIMBUS. The code is capable of repeating the JET analysis using the ITER geometry and SOL plasma. This allows assessment of whether the physical processes occurring in JET might also occur in ITER, and thus whether the JET results transfer, in any sense, to the ITER plasmas. Certainly, the ITER choice of wall materials (W and Be) is different than for the present JET C studies. So the present status of these studies is to relate JET carbon behavior to carbon in ITER.JET carbon sources were studied spectroscopically and analyzed with atomic physics models in EDGE2D. The carbon sources are dominated by chemical sputtering at rates which are within a factor-of-two of the published literature. The JET carbon contamination is dominated by main chamber sources which are ionized in the main chamber SOL about 1-2 cm from the separatrix. Contamination occurs from carbon ions which diffuse across the field lines and reach the separatrix before they can parallel transport to the divertor. JET carbon migration was studied by injecting methane composed of 13C on the last run day before an opening and then analyzing removed tiles to identify migration to those locations. Modeling was accomplished by the same EDGE2D models that were used to describe the carbon sources and contamination. The entire migration process is complicated.

  11. An urban aquifer and the presence of petroleum hydrocarbons

    International Nuclear Information System (INIS)

    Fredericton, New Brunswick gets most of its water supply from a glaciofluvial sand and gravel aquifer located beneath the downtown area. The near-surface accidental release of petroleum hydrocarbons above the aquifer and above discontinuities in the overlying aquitard has necessitated implementation of remedial measures at several locations. Three case studies are reviewed. At the Smythe Street School, ca 5,500 liters of heating oil were found to have leaked from a basement tank, penetrating into the underlying soil through cracks in the basement slab. Remedial measures included drilling an intercept well, soil venting, and bioremediation. Except for early peaks, fuel oil concentrations have not been detected in the recovery well or site monitoring wells. At a gasoline distributor, ca 1,000 liters of gasoline was released from a leaky underground tank. All tanks and 340 tonnes of soil were removed. A pump and treat system provided containment of the dissolved plume, which migrated within the shallow water table aquifer above the aquitard. At an office complex, over 36,000 liters of bunker C and fuel oil has been recovered from pumping activities after ground contamination was discovered during an underground tank replacement program. The viscous nature of the hydrocarbons means that the contaminants are mainly immobile, but low levels of hydrocarbons have been detected at monitoring wells downgradient of the site. The three cases studied do not pose a threat to the quality of the Fredericton water supply. 6 refs., 2 figs

  12. Hydrocarbon exploration risk evaluation through uncertainty and sensitivity analyses techniques

    International Nuclear Information System (INIS)

    The evaluation of the exploration risk in the oil industry is a fundamental component of the decision process related to the exploratory phase. In this paper the two basic components of the exploratory risk: trap geometry and trapped hydrocarbon quantities (fluid), are compounded in a single coherent uncertainty and sensitivity approach. The results clarify that the model geometry influences each Petroleum System Modeling step and that the geometric uncertainty is correlated with the fluid uncertainty. The geometric uncertainty evaluation makes use of geostatistical techniques that produce a number of possible realizations of the trap geometry, all compatible with available data. The evaluation of the fluid uncertainty, through a Monte Carlo methodology, allows us to compute the possible quantities of oil and gas, generated in a basin and migrated from the hydrocarbon source location to each single trap. The final result is the probability distribution of oil and gas for each trap in the basin, together with other useful indicators like: the hydrocarbon filling probability map, the closure probability map, the drainage area probability map, the spilling paths probabilities, the trap-filling scenarios

  13. Enrichment of light hydrocarbon mixture

    Energy Technology Data Exchange (ETDEWEB)

    Yang; Dali (Los Alamos, NM); Devlin, David (Santa Fe, NM); Barbero, Robert S. (Santa Cruz, NM); Carrera, Martin E. (Naperville, IL); Colling, Craig W. (Warrenville, IL)

    2010-08-10

    Light hydrocarbon enrichment is accomplished using a vertically oriented distillation column having a plurality of vertically oriented, nonselective micro/mesoporous hollow fibers. Vapor having, for example, both propylene and propane is sent upward through the distillation column in between the hollow fibers. Vapor exits neat the top of the column and is condensed to form a liquid phase that is directed back downward through the lumen of the hollow fibers. As vapor continues to ascend and liquid continues to countercurrently descend, the liquid at the bottom of the column becomes enriched in a higher boiling point, light hydrocarbon (propane, for example) and the vapor at the top becomes enriched in a lower boiling point light hydrocarbon (propylene, for example). The hollow fiber becomes wetted with liquid during the process.

  14. Enrichment of light hydrocarbon mixture

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Dali (Los Alamos, NM); Devlin, David (Santa Fe, NM); Barbero, Robert S. (Santa Cruz, NM); Carrera, Martin E. (Naperville, IL); Colling, Craig W. (Warrenville, IL)

    2011-11-29

    Light hydrocarbon enrichment is accomplished using a vertically oriented distillation column having a plurality of vertically oriented, nonselective micro/mesoporous hollow fibers. Vapor having, for example, both propylene and propane is sent upward through the distillation column in between the hollow fibers. Vapor exits neat the top of the column and is condensed to form a liquid phase that is directed back downward through the lumen of the hollow fibers. As vapor continues to ascend and liquid continues to countercurrently descend, the liquid at the bottom of the column becomes enriched in a higher boiling point, light hydrocarbon (propane, for example) and the vapor at the top becomes enriched in a lower boiling point light hydrocarbon (propylene, for example). The hollow fiber becomes wetted with liquid during the process.

  15. Iodine isothermal migration behaviour in titanium nitride

    Science.gov (United States)

    Gavarini, S.; Jaffrezic, H.; Martin, P.; Peaucelle, C.; Toulhoat, N.; Cardinal, S.; Moncoffre, N.; Pichon, C.; Tribet, M.

    2008-02-01

    Titanium nitride is one of the inert matrixes proposed to surround the fuel in gas cooled fast reactor (GFR) systems. These reactors will operate at high temperature and refractory materials with a high chemical stability and good mechanical properties are required. Furthermore, a total retention of the most volatile fission products, such as I, Xe or Cs, by the inert matrix is needed during the in-pile process. The isothermal migration of iodine in TiN was studied by implanting 800 keV I ++ ions in sintered samples at an ion fluence of 5 × 10 15 cm -2. Thermal treatments were performed under secondary vacuum at temperatures ranging from 1200 to 1700 °C. Iodine concentration profiles were determined by 2.5 MeV ?-particle elastic backscattering. The migration of iodine seems to be correlated with point defects created by implanted ions near the surface. The Arrhenius plot corresponding to iodine detrapping is curved with possibly two straight-line regions which could indicate either the presence of two types of traps, or a strong dependence of trap's concentration on temperature above 1500 °C. The activation energies associated with each linear region of the Arrhenius plot were found to be: Ea = 2.4 ± 0.2 eV below 1500 °C and E=11.4±0.2 eV above 1500 °C. Nitrogen evaporation from TiN surface under secondary vacuum was proposed as a contributing factor to the enhanced mobility of iodine at high temperature.

  16. Conceptual design of air sparge/soil vent systems for in situ remediation of petroleum hydrocarbons

    International Nuclear Information System (INIS)

    A conceptual design for a sparge and vent system is presented. A sparge and vent system consists of air sparging or in situ aeration in combination with soil vapor extraction. With air sparging, a compressed air source provides sparging of the ground water through aeration points, volatizes dissolved hydrocarbons, and elevates dissolved oxygen (DO) levels in the ground water. Volatile hydrocarbon vapors migrate more readily than liquid in soil, and are extracted to atmosphere with the vapor extraction system. Increased oxygen levels in the ground water and unsaturated soil promotes natural, aerobic biodegradation of the hydrocarbons without nutrient addition. Design considerations for sparge systems include spacing and depth of installation of the sparging points, air injection rates and pressures and the air source. The design techniques for the soil vapor extraction system have been discussed extensively in the literature but generally involve spacing of the extraction wells to capture all the hydrocarbons stripped from the ground water. The soil vapor extraction system can also be modified to enhance oxygen (air) delivery to the unsaturated zone and thus promote natural biodegradation of the petroleum hydrocarbons in the soil. Techniques for monitoring the progress of remediation include measurement of oxygen and carbon dioxide levels in the soil, DO levels in the ground water, subsurface air pressures and petroleum hydrocarbon levels in the discharged air, soil and ground water

  17. Migration Process Evolution in Europe

    Directory of Open Access Journals (Sweden)

    Carmen Tudorache

    2006-08-01

    Full Text Available The migration phenomenon has always existed, fluctuating by the historic context, the economic, political, social and demographic disparities between the Central and East European countries and the EU Member States, the interdependencies between the origin and receiving countries and the European integration process evolutions. In the European Union, an integrated and inclusive approach of the migration issue is necessary. But a common policy on migration rests an ambitious objective. A common approach of the economic migration management and the harmonization of the migration policies of the Member States represented a challenge for the European Union and will become urgent in the future, especially due to the demographic ageing.

  18. Migrations in Slovenian geography textbooks

    Directory of Open Access Journals (Sweden)

    Jurij Senega?nik

    2013-12-01

    Full Text Available In Slovenia, the migrations are treated in almost all geographical textbooks for different levels of education. In the textbooks for the elementary school from the sixth to ninth grade, students acquire knowledge of the migrations by the inductive approach. Difficulty level of treatment and quantity of information are increasing by the age level. In the grammar school program a trail of gaining knowledge on migration is deductive. Most attention is dedicated to migrations in general geography textbooks. The textbooks for vocational and technical school programs deal with migrations to a lesser extent and with different approaches.

  19. FUNGI AND HYDROCARBONS IN THE MARINE ENVIRONMENT

    Science.gov (United States)

    Hydrocarbons from various sources--anthropogenic pollution, marine seeps, marine algae, atmospheric fallout and terrestrial runoff--enter the ocean daily. These complex hydrocarbon mixtures are dispersed and degraded by abiotic and biogenic processes. Most commonly, bacteria are ...

  20. Secondary ion mass spectrometry for the identification of polymers with noncharacteristic secondary ions using multivariate statistical analysis

    International Nuclear Information System (INIS)

    Eleven different, filler-free polymers were depth profiled until all secondary ion signals were stable. Discriminant function analysis and principal components analysis were performed on a dataset containing the intensities of noncharacteristic hydrocarbon secondary ions, measured in this steady state. Discriminant function analysis showed that these secondary ions were sufficient to correctly identify all polymers using leave-one-out correction. Even with principal components analysis, which uses no prior knowledge about the origin of a data point, identification was shown to be possible

  1. Assessment and remediation of hydrocarbons at the Colomac Mine site

    Energy Technology Data Exchange (ETDEWEB)

    Boys, C. [Dillon Consulting Ltd., Calgary, AB (Canada)

    2001-07-01

    Several hydrocarbon spills have occurred during the life of the Colomac Gold Mine, which is located in the Taiga Shield ecozone, 220 km north of Yellowknife in the Northwest Territories. This paper describes the issues and complications inherent in the characterization and remediation of the contaminated site. The mine lies within a permafrost zone and has been operated as a fly-in operation, with access available via an ice-road for 3 months during the winter. In 1999, the Department of Indian Affairs and Northern Development (DIAND) took control of the mine when the mine was put into receivership. Outstanding issues included a tailings facility, mine facilities and debris, and significant hydrocarbon contamination resulting from several spills and leaks that occurred throughout the history of the mine. The most significant spills were in early 1990 and in 1997, each spilling approximately 20,000 litres of diesel fuel. The spills were cleaned and contained with an absorbent boom and pads. In February 2000, an extensive study of the hydrocarbon impacts was conducted. Liquid petroleum hydrocarbon was detected in 20 of 42 monitoring wells in the areas of the tank farm, fueling facilities, power house and garage. The average depth of product was 4.5 metres, while the apparent thickness ranged from less than 1 cm to 15 metres. The two main remedial goals were to control the plume to prevent down-gradient migration into Steeves Lake, and to extract the free product and burn it offsite. The best ways to accomplish these goals is to build a trench system or to extract the oil using high vacuum extraction from existing wells. Treatment of any impacted groundwater will be reevaluated once the liquid product and contaminated soil is removed. Groundwater treatment options include natural attenuation, nutrient addition and air sparging. 3 refs., 2 figs.

  2. Effective viscosity of confined hydrocarbons

    DEFF Research Database (Denmark)

    Sivebæk, Ion Marius; Samoilov, V.N.; Persson, B.N.J.

    2012-01-01

    We present molecular dynamics friction calculations for confined hydrocarbon films with molecular lengths from 20 to 1400 carbon atoms. We find that the logarithm of the effective viscosity ?eff for nanometer-thin films depends linearly on the logarithm of the shear rate: log ?eff=C-nlog ??, where...

  3. Steam Hydrocarbon Cracking and Reforming

    Science.gov (United States)

    Golombok, Michael

    2004-01-01

    The interactive methods of steam hydrocarbon reforming and cracking of the oil and chemical industries are scrutinized, with special focus on their resemblance and variations. The two methods are illustrations of equilibrium-controlled and kinetically-controlled processes, the analysis of which involves theories, which overlap and balance each…

  4. Population, desertification, and migration.

    Science.gov (United States)

    Westing, A H

    1994-01-01

    When an imbalance develops between population numbers and the carrying capacity of the land, the persons thereby displaced are referred to as environmental refugees. The utilization of the land beyond sustainability leads to land degradation and ultimately, desertification. The social and political impacts of long-term environmental migration can be distinguished: a) at the site of origin of the displaced persons by the residual population; b) at rural sites of destination within the nation between the new arrivals and preestablished populations; c) in the cities within the nation; d) in the nonindustrialized foreign countries; and e) in the industrialized foreign countries. In the event that an area which had previously been devoted to pastoralism is converted to agriculture, the displaced pastoralists might respond through armed rebellion. In some instances, the disenchanted urban squatters become a politically restive and even a destabilizing force, as occurred in Sudan in the 1980s, especially in Khartoum and Port Sudan. The foreign countries to which many of the displaced persons are migrating are subjected to increasing levels of migrant-induced economic, cultural, and political strains. The growing problems associated with south-to-north migration across the Mediterranean Sea have recently led France, Italy, Portugal, and Spain to enter into a consultative arrangement with Algeria, Libya, Mauritania, Morocco, and Tunisia. All foreign aid to the nonindustrialized countries that attempts to ameliorate the problem of desertification must adopt integrated approaches that: a) address population issues; b) support environmental education; c) provide for the protection of biodiversity; d) encourage participatory forms of local and national government; e) provide opportunities for income generation outside the livestock sector; and f) foster political security and facilitate ecogeographical (subregional) cooperation. PMID:12289925

  5. The Dnieper-Donets Paleorift, Ukraine: deep structures and hydrocarbon accumulations

    Energy Technology Data Exchange (ETDEWEB)

    Chekunov, A.V.; Kaluzhnaya, L.T. (AN Ukrainskoj SSR, Kiev (Ukraine). Inst. Geofiziki); Ryabchun, L.I. (AN Ukrainskoj SSR, Kiev (Ukraine). Inst. Geologicheskikh Nauk)

    1993-04-01

    Numerous deep seismic and borehole studies have been made in the Dnieper-Donets Paleorift (Ukraine), and, when combined with studies of oil- and gasfield distribution, indicate that there exists an interesting relationship between deep lithospheric structure and evolution, and the hydrocarbon potential of the Paleorift. It has been found that hydrocarbon accumulations tend to be associated with slopes in the Moho dicontinuity, where most faults are located, and also where the basement and the lower layers of sedimentary cover have been fragmented by faults. These areas are the most promising for exploration. These facts could imply an abiogenic, mantle origin for oil and gas. Alternatively, the hot mantle ascending beneath the Dnieper-Donets Paleorift may have created thermodynamic or fluid-flow conditions within the sedimentary cover which were favourable for the transformation of biogenic material into oil and gas. In this case, mantle fluid-flow along faults assisted the migration of hydrocarbons and its accumulation in traps. (author)

  6. Durability of fluorinated high density polyethylene (F-HDPE) geomembrane exposed to hydrocarbons in the Arctic

    Energy Technology Data Exchange (ETDEWEB)

    Rimal, S.; Rowe, R.K.; Bathurst, R.J. [Queen' s Univ., Kingston, ON (Canada). Dept. of Civil Engineering, Geoengineering Centre

    2007-07-01

    A hydrocarbon spill in the Canadian Arctic has been controlled with a geosynthetic clay liner (GCL) composed of a fluorinated high-density polyethylene (f-HDPE) geomembrane. The liner controlled the advective and diffusive migration of the hydrocarbons. This study examined the antioxidant depletion and the compatibility of both untreated and fluorinated high density polyethylene (HDPE) geomembranes with hydrocarbons. The objective was to determine the durability and long term performance of the HDPE geomembrane. Geomembrane swatches retrieved from the field site were examined for changes in oxidative induction time, crystallinity, tensile properties and dimensions. Laboratory results revealed that the properties of the buried 1.5 mm thick f-HDPE geomembranes have not been significantly altered since installation. The durability of the f-HDPE geomembrane was maintained for more than the designed service life of the liner. 26 refs., 1 tab., 8 figs.

  7. Ambient aromatic hydrocarbon measurements at Welgegund, South Africa

    Science.gov (United States)

    Jaars, K.; Beukes, J. P.; van Zyl, P. G.; Venter, A. D.; Josipovic, M.; Pienaar, J. J.; Vakkari, V.; Aaltonen, H.; Laakso, H.; Kulmala, M.; Tiitta, P.; Guenther, A.; Hellén, H.; Laakso, L.; Hakola, H.

    2014-07-01

    Aromatic hydrocarbons are associated with direct adverse human health effects and can have negative impacts on ecosystems due to their toxicity, as well as indirect negative effects through the formation of tropospheric ozone and secondary organic aerosol, which affect human health, crop production and regional climate. Measurements of aromatic hydrocarbons were conducted at the Welgegund measurement station (South Africa), which is considered to be a regionally representative background site. However, the site is occasionally impacted by plumes from major anthropogenic source regions in the interior of South Africa, which include the western Bushveld Igneous Complex (e.g. platinum, base metal and ferrochrome smelters), the eastern Bushveld Igneous Complex (platinum and ferrochrome smelters), the Johannesburg-Pretoria metropolitan conurbation (> 10 million people), the Vaal Triangle (e.g. petrochemical and pyrometallurgical industries), the Mpumalanga Highveld (e.g. coal-fired power plants and petrochemical industry) and also a region of anticyclonic recirculation of air mass over the interior of South Africa. The aromatic hydrocarbon measurements were conducted with an automated sampler on Tenax-TA and Carbopack-B adsorbent tubes with heated inlet for 1 year. Samples were collected twice a week for 2 h during daytime and 2 h during night-time. A thermal desorption unit, connected to a gas chromatograph and a mass selective detector was used for sample preparation and analysis. Results indicated that the monthly median (mean) total aromatic hydrocarbon concentrations ranged between 0.01 (0.011) and 3.1 (3.2) ppb. Benzene levels did not exceed the local air quality standard limit, i.e. annual mean of 1.6 ppb. Toluene was the most abundant compound, with an annual median (mean) concentration of 0.63 (0.89) ppb. No statistically significant differences in the concentrations measured during daytime and night-time were found, and no distinct seasonal patterns were observed. Air mass back trajectory analysis indicated that the lack of seasonal cycles could be attributed to patterns determining the origin of the air masses sampled. Aromatic hydrocarbon concentrations were in general significantly higher in air masses that passed over anthropogenically impacted regions. Inter-compound correlations and ratios gave some indications of the possible sources of the different aromatic hydrocarbons in the source regions defined in the paper. The highest contribution of aromatic hydrocarbon concentrations to ozone formation potential was also observed in plumes passing over anthropogenically impacted regions.

  8. Hydrocarbon and by-product reserves in British Columbia 1995

    International Nuclear Information System (INIS)

    Oil, gas, and gas by-product reserves in British Columbia were reviewed. A historical record of compiled data of British Columbia's reserves of crude oil and natural gas liquids from 1962 to 1995 were presented. A summary of the progress achieved during 1995 regarding horizontal oil and gas well technology, secondary and tertiary recovery, under-balanced drilling, and unconnected reserves was included. Detailed basic data on a field/pool/project basis was provided for crude oil reserves, raw gas reserves, pool gas analysis reports, and remaining hydrocarbon by-products

  9. Issues of Labor Migration

    Directory of Open Access Journals (Sweden)

    Liliana Gheorghe

    2010-12-01

    Full Text Available Factors of production are resources available, attracted and utilized in economic activity, namely in the production of material goods and services. Productive resources such as land, minerals, construction, machinery and equipment manufacturing, energy, water, knowledge and experience, information, resources are crucial for a country’s economy. In this context, taking account of current policy and socio - political - ecomonic, both globally and nationally, the country’s European Union integration perspective, this paper aims to bring to the fore the issue of labor migration.

  10. Migration and loving

    OpenAIRE

    Gevrek, Deniz

    2010-01-01

    This paper explores the relationship between anti-miscegenation laws, interracial marriage and black males' geographical distribution in the U.S. during and after the Great Migration. The U.S. Supreme Court decision in the case of Loving v. Virginia in 1967, which forced the last 16 Southern states to strike down their anti-miscegenation laws, creates a unique opportunity to explore the impact of an exogenous change in a state's laws regulating interracial marriages. Analyzing the U.S. Census...

  11. Globalization, migration and health.

    Science.gov (United States)

    Burnett, Angela

    2002-01-01

    The term 'globalization' describes the integration of economic systems through improved communication, but it also represents increased insecurity for those with few resources--particularly refugees. This article examines why people migrate, their numbers, constraints on their movement and their particular health care needs. Immigrants have much to contribute to their recipient countries, but at some loss to their homelands. Both economically and morally, more liberal immigration policies would be beneficial. Policies towards asylum seekers should not be more restrictive in the aftermath of 11 September 2001 and detention should be the exception rather than the rule. Globalization should be managed so as to improve people's lives throughout the world. PMID:11917962

  12. Amenity migration and tourism.

    Czech Academy of Sciences Publication Activity Database

    Bartoš, Michael; Kušová, Drahomíra; T?šitel, Jan

    Tábor : University of South Bohemia ?eské Bud?jovice, University of Economics Bratislava, 2005 - (Hesková, M.; Šittler, E.; Dvo?ák, V.), s. 17-21 ISBN 80-7040-766-2. [Tourism, regional development and education . Sustainable development and tourism. Tábor (CZ), 12.05.2005-13.05.2005] Grant ostatní: EU(XE) European Union/'s Quality of Life and Management of Living Resources programme:QLK5-CT-2000-01211-SPRITE Institutional research plan: CEZ:AV0Z60870520 Keywords : sustainable tourism * amenity migration * regional development Subject RIV: AE - Management ; Administration

  13. Prediction of cold start hydrocarbon emissions of air cooled two wheeler spark ignition engines by simple fuzzy logic simulation

    Directory of Open Access Journals (Sweden)

    Samuel Raja Ayyanan

    2014-01-01

    Full Text Available The cold start hydrocarbon emission from the increasing population of two wheelers in countries like India is one of the research issues to be addressed. This work describes the prediction of cold start hydrocarbon emissions from air cooled spark ignition engines through fuzzy logic technique. Hydrocarbon emissions were experimentally measured from test engines of different cubic capacity, at different lubricating oil temperature and at different idling speeds with and without secondary air supply in exhaust. The experimental data were used as input for modeling average hydrocarbon emissions for 180 seconds counted from cold start and warm start of gasoline bike engines. In fuzzy logic simulation, member functions were assigned for input variables (cubic capacity and idling rpm and output variables (average hydrocarbon emission for first 180 seconds at cold start and warm start. The knowledge based rules were adopted from the analyzed experimental data and separate simulations were carried out for predicting hydrocarbon emissions from engines equipped with and without secondary air supply. The simulation yielded the average hydrocarbon emissions of air cooled gasoline engine for a set of given input data with accuracy over 90%.

  14. Migration and sensory changes of packaging materials caused by ionising radiation

    International Nuclear Information System (INIS)

    Irradiation of packaging materials--in most cases plastics--generally lead to a formation of free radicals and ions, with secondary effects such as cross-linking as well as oxidative chain scission. These effects result in a formation of volatile radiolysis products which may induce off-odours in the polymers and may change the migration characteristics of packaging materials. Irradiation affect also polymer additives which change the specific migration behaviour of polymer additives and additive related decomposition products. Migration and sensory changes of pre-sterilised packaging materials have consequences on the quality of packaged goods and consumer's safety. Therefore, migration and sensory properties of packaging materials have specific regulations. Within this paper the effects of the formation of radiolysis products on overall migration, specific migration of food additives or radiolysis products as well as on sensory changes are discussed in view of current European food law

  15. Accelerated diffusion controlled creep of polycrystalline materials. Communication 2. Model of decelerated grain boundary migration under conditions of diffusion controlled creep

    International Nuclear Information System (INIS)

    The process of large-angle grain boundary migration under conditions of Coble diffusion controlled creep is investigated theoretically. It is revealed that the rate of grain boundary migration under conditions of diffusion controlled creep is considerably lower than that under conditions of secondary recrystallization. This deceleration is related to the change of grain boundary mobility due to defect accumulation at grain boundaries during their migration. The model of grain boundary migration under diffusion controlled creep is developed

  16. Fluid Inclusions Usage for Assessing Oil Migration in Duhok, North Iraq

    OpenAIRE

    Salih Muhammad Awadh; Mehmet S. Bayraktutan; Sahar Y. Jassim; Thamer K. Al-Ameri

    2010-01-01

    Studies of primary and secondary fluid inclusions were done on epigenetic barite samples collected from carbonates of Lower part of Sarmord Formation (Lower Cretaceous) and Aqra-Bekhme Formations (Upper Cretaceous) in Duhok, north Iraq. Lead isotopes composition in galena which associated barite that contained fluid inclusions helped the identification two events of fluid inclusions. These fluid inclusions contain brine water and hydrocarbons. Primary and secondary fluid inclusions in barite ...

  17. Europe: Migration and Development

    Scientific Electronic Library Online (English)

    Harris, Nigel.

    2006-06-01

    Full Text Available La actitud de los gobiernos hacia la migración -interna y externa- ha cambiado en forma radical en años recientes. Considerada anteriormente como evidencia de una descomposición crónica social y económica así como una seria amenaza para el poder gubernamental (bajo una urbanización acelerada), la mi [...] gración interna es vista actualmente como un mecanismo muy importante para la redistribución de recursos de las localidades más ricas hacia las más pobres y un medio vital para elevar el ingreso de la población de estas áreas. El mismo cambio de percepción se está presentando sobre la migración internacional. En este caso, los flujos de remesas de trabajadores que laboran en el exterior hacia sus familias en sus lugares de origen se han convertido en un componente relevante en el ingreso de divisas de un gran número de países. Al cabo de ciertas reticencias, los gobiernos ahora han venido aceptando la migración por trabajo, con el fin de facilitar y reforzar sus efectos sobre la paliación de la pobreza. Sin embargo, se presentan algunos problemas con la pérdida de los trabajadores más emprendedores y con mayor calificación en los países en desarrollo. ¿Pueden reconciliarse los intereses en juego -países en desarrollo, migrantes, países desarrollados-?. La migración temporal circulatoria con propósitos de capacitación parecería ser el mejor resultado, de tal manera que la migración se convirtiera en un medio para potenciar el capital humano de los países en desarrollo en la tarea de reducir la pobreza mundial. Existen, no obstante, muchas opciones sin inmigración para los países desarrollados, desde reformas a sus mercados laborales internos hasta la subcontratación en el exterior. La alternativa real tiene que ver con la clase de mundo que deseamos. Abstract in english Government attitudes to migration -internal and external- have changed radically in recent years. Formerly seen as evidence of chronic social and economic breakdown and major threats to government power (in accelerated urbanisation), internal migration is now seen as major mechanism for the redistri [...] bution of resources from richer to poorer localities and a vital means of raising the incomes of the poor. The same revision of view is affecting international migration. Here remittance flows from workers working abroad to their families at home have become major components in the foreign exchange earnings of a number of countries. After some reluctance, governments have come to embrace emigration for work, to facilitate and reinforce its effects on the alleviation of poverty. However, there are problems in the loss of the most enterprising and best-trained workers of developing countries. Can the interests at stake -developing countries, migrants, developed countries- be reconciled? Temporary circulatory migration for the purposes of training would seem to be the best outcome, so that migration becomes a means to enhance the human capital of developing countries for the task of reducing world poverty. There are, however, many options for developed countries without immigration - from the reform of their domestic labour markets to off-shoring. The real choice is about what sort of world we want.

  18. Syngas Upgrading to Hydrocarbon Fuels Technology Pathway

    Energy Technology Data Exchange (ETDEWEB)

    Talmadge, M.; Biddy, M.; Dutta, A.; Jones, S.; Meyer, A.

    2013-03-01

    This technology pathway case investigates the upgrading of woody biomass derived synthesis gas (syngas) to hydrocarbon biofuels. While this specific discussion focuses on the conversion of syngas via a methanol intermediate to hydrocarbon blendstocks, there are a number of alternative conversion routes for production of hydrocarbons through a wide array of intermediates from syngas. Future work will also consider the variations to this pathway to determine the most economically viable and lowest risk conversion route. Technical barriers and key research needs have been identified that should be pursued for the syngas-to-hydrocarbon pathway to be competitive with petroleum-derived gasoline-, diesel- and jet-range hydrocarbon blendstocks.

  19. Biodegradation of petroleum hydrocarbons in hypersaline environments

    Scientific Electronic Library Online (English)

    Luiz Fernando, Martins; Raquel Silva, Peixoto.

    2012-09-01

    Full Text Available Literature on hydrocarbon degradation in extreme hypersaline media presents studies that point to a negative effect of salinity increase on hydrocarbonoclastic activity, while several others report an opposite tendency. Based on information available in the literature, we present a discussion on the [...] reasons that justify these contrary results. Despite the fact that microbial ability to metabolize hydrocarbons is found in extreme hypersaline media, indeed some factors are critical for the occurrence of hydrocarbon degradation in such environments. How these factors affect hydrocarbon degradation and their implications for the assessment of hydrocarbon biodegradation in hypersaline environments are presented in this review.

  20. Data Migration Across The Clouds

    OpenAIRE

    Prashant Pant,; Mr.Sanjeev Thakur,

    2013-01-01

    Having an effective and efficient strategy for optimizing long distance data migration is essential for every data center. With the ever increasing demands for the IT needs of businesses it is also important for data centers to deliver data migration cost effectively especially when faced with the demands from remote office back up, outsourcing, data center movers and cloud computing. Data management and migration are important research challenges of novel Cloud environments. While moving dat...

  1. Anomalous dynamics of cell migration

    OpenAIRE

    Dieterich, P.; Klages, R.; Preuss, R.; A. Schwab

    2009-01-01

    Cell movement—for example, during embryogenesis or tumor metastasis—is a complex dynamical process resulting from an intricate interplay of multiple components of the cellular migration machinery. At first sight, the paths of migrating cells resemble those of thermally driven Brownian particles. However, cell migration is an active biological process putting a characterization in terms of normal Brownian motion into question. By analyzing the trajectories of wild-type and mutated epithelial (...

  2. Nuclear Migration During Retinal Development

    OpenAIRE

    Baye, Lisa M.; Link, Brian A.

    2007-01-01

    In this review we focus on the mechanisms, regulation, and cellular consequences of nuclear migration in the developing retina. In the nervous system, nuclear migration is prominent during both proliferative and post-mitotic phases of development. Interkinetic nuclear migration is the process where the nucleus oscillates from the apical to basal surfaces in proliferative neuroepithelia. Proliferative nuclear movement occurs in step with the cell cycle, with M-phase being confined to the apica...

  3. The challenges of managing migration

    Energy Technology Data Exchange (ETDEWEB)

    Tacoli, Cecilia

    2005-10-15

    Migration and urbanisation are driven by economic growth and social change, but also by deepening inequalities. Managing migration should not be equated with curbing it, as this inevitably reduces migrants' rights. But managing population movement whilst respecting the rights of migrants and nonmigrants, supporting the contribution of migration to poverty reduction and economic growth in sending and receiving areas and reducing the human and material costs of movement means that fundamental challenges need to be addressed.

  4. Geometric Control of Cell Migration

    OpenAIRE

    Bo Chen; Girish Kumar; Carlos C. Co; Chia-Chi Ho

    2013-01-01

    Morphological polarization involving changes in cell shape and redistribution of cellular signaling machinery, initiate the migration of mammalian cells. Golgi complex typically localizes in front of the nucleus, and this frontwards polarization has been proposed to be involved in directional migration. However, the sequence of events remains unresolved. Does Golgi polarization precede directional migration or vice-versa? We address this question by constraining cells to specific areas and sh...

  5. Macrostabilization of the Migration Phenomenon

    Directory of Open Access Journals (Sweden)

    Cristina Burghelea

    2014-03-01

    Full Text Available MacLabour migration is a present phenomenon in the European Union. This phenomenon takes over the entire European continent, but especially in the EU countries. The labor market in Europe is increasingly affected by population aging. Economic differences between European countries make workforce in developing countries to move to developed countries where they find it easier to work and receive higher remuneration than in their home countries. This article tracks labor migration from/to EU, employment in Romania and Romanian migration towards the countries of Western Europe. It also presents statistics on labor migration in the EU and its impact on the labor market

  6. Migration and fate of ethanol-enhanced gasoline in groundwater: A modelling analysis of a field experiment

    Science.gov (United States)

    Freitas, Juliana G.; Mocanu, Marian T.; Zoby, José Luiz G.; Molson, John W.; Barker, James F.

    2011-01-01

    Ethanol use as a gasoline additive is increasing, as are the chances of groundwater contamination caused by gasoline releases involving ethanol. To evaluate the impact of ethanol on dissolved hydrocarbon plumes, a field test was performed in which three gasoline residual sources with different ethanol fractions (E0: no ethanol, E10: 10% ethanol and E95: 95% ethanol) were emplaced below the water table. Using the numerical model BIONAPL/3D, the mass discharge rates of benzene, toluene, ethylbenzene, xylenes, trimethylbenzenes and naphthalene were simulated and results compared to those obtained from sampling transects of multilevel samplers. It was shown that ethanol dissolved rapidly and migrated downgradient as a short slug. Mass discharge of the hydrocarbons from the E0 and E10 sources suggested similar first-order hydrocarbon decay rates, indicating that ethanol from E10 had no impact on hydrocarbon degradation. In contrast, the estimated hydrocarbon decay rates were significantly lower when the source was E95. For the E0 and E10 cases, the aquifer did not have enough oxygen to support complete mineralization of the hydrocarbon compounds to the extent suggested by the field-based mass discharge. Introducing a heterogeneous distribution of hydraulic conductivity did little to overcome this discrepancy. A better match between the numerical model and the field data was obtained assuming partial degradation of the hydrocarbons to intermediate compounds. Besides depending on the ethanol concentration, the impact of ethanol on hydrocarbon degradation appears to be highly dependent on the availability of electron acceptors.

  7. Radiological Management of Superior Vena Caval Stent Migration and Infection

    International Nuclear Information System (INIS)

    We report a case of venous obstruction secondary to Hodgkin's lymphoma. Multiple Wallstents were inserted into the superior vena cava to relieve obstructive symptoms secondary to tumor. This procedure was complicated by stent migration into the right ventricle and a presumed stent infection. We describe the percutaneous management of these complications and discuss the issues surrounding the use of stents in this setting. We conclude that these complications can be managed percutaneously. However, the technical details of stent placement are essential in minimizing complications of this type

  8. Wnts induce migration and invasion of myeloma plasma cells.

    Science.gov (United States)

    Qiang, Ya-Wei; Walsh, Katie; Yao, Lei; Kedei, Noemi; Blumberg, Peter M; Rubin, Jeffrey S; Shaughnessy, John; Rudikoff, Stuart

    2005-09-01

    Multiple myeloma is an incurable form of lymphoid cancer characterized by accumulation of neoplastic plasma cells in the bone marrow cavity. Little is known about the mechanisms regulating myeloma cell movement within the bone marrow and metastasis to secondary sites. Herein, we identify multiple members of the wingless/int (Wnt) family as promoters of myeloma cell migration/invasion. Wnt-mediated migration was associated with the Wnt/RhoA pathway and did not necessitate signaling through beta-catenin. Activation of both RhoA and members of the protein kinase C (PKC) family, including PKCalpha, PKCbeta, and PKCmu, were required for induction of migration. Activated RhoA and PKCalpha, PKCbeta, and PKCmu appear to assemble in macromolecular signaling complexes that are associated with the cell membrane. These results suggest that Wnt responsiveness of myeloma plasma cells may be a significant factor in disease progression. PMID:15886323

  9. Study of migration behavior of technogenic radionuclides in the Yenisey River-Kara Sea aquatic system

    International Nuclear Information System (INIS)

    For 35 years Krasnoyarsk Mining-Chemical Combine (MCC) manufactures weapon plutonium in single-pass production reactors cooled with water of the Yenisey River. Water discharge from these reactors is the major source of radioactive contamination of the Yenisey River. We have demonstrated that after putting the reactors out of operation (in late 1992) the contamination level of the Yenisey River with short-lived radionuclides considerably decreased, and now the radioactive contamination is caused essentially by Cs-137, Eu-152, Pu-239,240, Sr-90, and Am-241, whose concentration in the aqueous phase is lower than in bottom sediments and, particularly, flood-land deposits by several orders of magnitude (except for Sr-90). The flood-land deposits are classified with the most contaminated environmental objects in the territories under the impact of MCC: their radioactivity is comparable with that of low-level waste. Taking into account the considerable depth and area of the flood-land deposits, this allows their classification as a great technogenic radiation anomaly. Comparison of the maximal Cs-137 and Pu-239,240 levels in flood-land soils and bottom sediments of the Yenisey River with those in bottom sediments of the Pripyat' River and the Kiev reservoir shows that these values are close each to other. A direct correlation is found between the spatial distribution of Cs-137 on the one hand and Pu-239,240, Eu-152, and Am-241 on the other hand in the aqueous phase and bottom sediments, which is not the case for Sr-90. Data on the distribution coefficients of the indicated radionuclides between the deposits and aqueous phase (obtained with actual and model systems) and also on the radionuclide distribution throughout geochemical mobility forms suggest that the essential part of Cs, Pu, Eu, and Am migrates with fine-disperse suspended material, the transport and distribution of which is controlled by the hydrological regime of the Yenisey River. By contrast, strontium migrates as soluble species weakly sorbed by the solid phase, causing the observed low content of Sr-90 in flood-land deposits and bottom sediments of the Yenisey River. The indicated migration behavior of radionuclides is characteristic of the Yenisey Gulf and the adjacent part of the Kara Sea also. We made similar conclusions when studying the migration behavior of Cs-137, Pu-239,240, and Sr-90 in the Kiev reservoir (1987). The formation of radioactive flood-land deposits is provided by rapid deposition of suspended material in stagnant zones during periodical flood. Humus compounds contribute significantly to accumulation of radionuclides in the flood-land deposits and bottom sediments, which is supported by the observed correlation between the radionuclide (Pu, Am, Eu) and total organic carbon distributions in them. Radiochemical analysis of separate fractions showed that about 20% of Pu and Am are associated with the organic fraction: Pu is nearly equally distributed between humic and fulvic acid fractions, whereas Am is preferentially associated with the fulvic acid fraction (the most mobile fraction of humus matter). It was demonstrated in model experiments that the calcium-hydrocarbonate type of water of the Yenisey River causes suppression of formation of mobile fulvate complexes of hydrolyzable radionuclides and, therefore, their transfer into the aqueous phase. In combination with the observed very high distribution coefficients of the radionuclides and low content of their mobile geochemical forms in flood-land deposits of the Yenisey River this suggest that they cannot contribute somewhat significantly to the secondary radioactive contamination of the river water by all mechanisms except migration by mechanical transfer. (author)

  10. Study of migration behavior of technogenic radionuclides in the Yenisey River-Kara Sea aquatic system

    Energy Technology Data Exchange (ETDEWEB)

    Kuznetsov, Yu.; Legin, E.; Legin, V. [Khlopin Radium Institute, St. Petersburg (Russian Federation); Shishlov, A.; Savitskii, Yu. [Krasnoyarsk Mining and Chemical Combine, Krasnoyarsk (Russian Federation); Novikov, A.; Goryachenkova, T. [Russian Academy of Sciences, Institute of Geochemistry and Analytical Chemistry, Moscow (Russian Federation)

    2001-03-01

    For 35 years Krasnoyarsk Mining-Chemical Combine (MCC) manufactures weapon plutonium in single-pass production reactors cooled with water of the Yenisey River. Water discharge from these reactors is the major source of radioactive contamination of the Yenisey River. We have demonstrated that after putting the reactors out of operation (in late 1992) the contamination level of the Yenisey River with short-lived radionuclides considerably decreased, and now the radioactive contamination is caused essentially by Cs-137, Eu-152, Pu-239,240, Sr-90, and Am-241, whose concentration in the aqueous phase is lower than in bottom sediments and, particularly, flood-land deposits by several orders of magnitude (except for Sr-90). The flood-land deposits are classified with the most contaminated environmental objects in the territories under the impact of MCC: their radioactivity is comparable with that of low-level waste. Taking into account the considerable depth and area of the flood-land deposits, this allows their classification as a great technogenic radiation anomaly. Comparison of the maximal Cs-137 and Pu-239,240 levels in flood-land soils and bottom sediments of the Yenisey River with those in bottom sediments of the Pripyat' River and the Kiev reservoir shows that these values are close each to other. A direct correlation is found between the spatial distribution of Cs-137 on the one hand and Pu-239,240, Eu-152, and Am-241 on the other hand in the aqueous phase and bottom sediments, which is not the case for Sr-90. Data on the distribution coefficients of the indicated radionuclides between the deposits and aqueous phase (obtained with actual and model systems) and also on the radionuclide distribution throughout geochemical mobility forms suggest that the essential part of Cs, Pu, Eu, and Am migrates with fine-disperse suspended material, the transport and distribution of which is controlled by the hydrological regime of the Yenisey River. By contrast, strontium migrates as soluble species weakly sorbed by the solid phase, causing the observed low content of Sr-90 in flood-land deposits and bottom sediments of the Yenisey River. The indicated migration behavior of radionuclides is characteristic of the Yenisey Gulf and the adjacent part of the Kara Sea also. We made similar conclusions when studying the migration behavior of Cs-137, Pu-239,240, and Sr-90 in the Kiev reservoir (1987). The formation of radioactive flood-land deposits is provided by rapid deposition of suspended material in stagnant zones during periodical flood. Humus compounds contribute significantly to accumulation of radionuclides in the flood-land deposits and bottom sediments, which is supported by the observed correlation between the radionuclide (Pu, Am, Eu) and total organic carbon distributions in them. Radiochemical analysis of separate fractions showed that about 20% of Pu and Am are associated with the organic fraction: Pu is nearly equally distributed between humic and fulvic acid fractions, whereas Am is preferentially associated with the fulvic acid fraction (the most mobile fraction of humus matter). It was demonstrated in model experiments that the calcium-hydrocarbonate type of water of the Yenisey River causes suppression of formation of mobile fulvate complexes of hydrolyzable radionuclides and, therefore, their transfer into the aqueous phase. In combination with the observed very high distribution coefficients of the radionuclides and low content of their mobile geochemical forms in flood-land deposits of the Yenisey River this suggest that they cannot contribute somewhat significantly to the secondary radioactive contamination of the river water by all mechanisms except migration by mechanical transfer. (author)

  11. Kirchhoff migration without phases

    CERN Document Server

    Bardsley, Patrick

    2016-01-01

    We present a simple, frequency domain, preprocessing step to Kirchhoff migration that allows the method to image scatterers when the wave field phase information is lost at the receivers, and only intensities are measured. The resulting imaging method does not require knowing the phases of the probing field or manipulating the phase of the wave field at the receivers. In a regime where the scattered field is small compared to the probing field, the problem of recovering the full-waveform scattered field from intensity data can be formulated as an embarrassingly simple least-squares problem. Although this only recovers the projection (on a known subspace) of the full-waveform scattered field, we show that, for high frequencies, this projection gives Kirchhoff images asymptotically identical to the images obtained with full waveform data. Our method can also be used when the source is modulated by a Gaussian process and autocorrelations are measured at an array of receivers.

  12. Migration and women's health.

    Science.gov (United States)

    Adanu, Richard M K; Johnson, Timothy R B

    2009-08-01

    Women have been migrating at similar rates to men for the past 40 years, and comprised about half of all migrants in 2005. Women and children are most affected by displacement as a result of wars and human trafficking. In some cases, the health of female migrants is improved via integration into better health systems in the host country. More often, however, the health of female migrants is affected negatively. Women are doubly disadvantaged because they are discriminated against as women and as migrants. Female migrants are also highly vulnerable to acts of sexual abuse, rape, and violence. This is especially true for women in refugee camps, whose reproductive health needs are often overlooked. To improve the health of female migrants it is important to develop and implement policies that recognize and insist on the respect of the rights of migrants. PMID:19539929

  13. Chandra Contaminant Migration Model

    Science.gov (United States)

    Swartz, Douglas A.; O'Dell, Steve L.

    2014-01-01

    High volatility cleans OBFs and low volatility produces a high build-up at OBF centers; only a narrow (factor of 2 or less) volatility range produces the observed spatial pattern. Simulations predict less accumulation above outer S-array CCDs; this may explain, in part, gratings/imaging C/MnL discrepancies. Simulations produce a change in center accumulation due solely to DH heater ON/OFF temperature change; but a 2nd contaminant and perhaps a change in source rate is also required. Emissivity E may depend on thickness; another model parameter. Additional physics, e.g., surface migration, is not warranted at this time. At t approx. 14 yrs, model produced 0.22 grams of contaminant, 0.085 grams remaining within ACIS cavity; 7 percent (6mg) on OBFs.

  14. Objectivity Data Migration

    CERN Document Server

    Nowak, M; Valassi, Andrea; Lubeck, M; Geppert, D; Geppert, Dirk

    2003-01-01

    In this article we describe the migration of event data collected by the COMPASS and HARP experiments at CERN. Together these experiments have over 300TB of physics data stored in Objectivity/DB that had to be transferred to a new data management system by the end of Q1 2003 and Q2 2003 respectively. To achieve this, data needed to be processed with a rate close to 100MB/s, employing 14 tape drives and a cluster of 30 Linux servers. The new persistency solution to accommodate the data is built upon relational databases for metadata storage and standard "flat" files for the event data. The databases contain collections of 109 events and allow generic queries or direct navigational access to the data, preserving the original C++ user API. The central data repository at CERN is implemented using several Oracle9i servers on Linux and the CERN Mass Storage System CASTOR.

  15. Endobronchial valve migration.

    Science.gov (United States)

    Jenkins, Melanie; Vaughan, Paul; Place, David; Kornaszewska, Malgorzata

    2011-11-01

    Endobronchial valves are increasingly used as a treatment modality as a less invasive alternative to lung volume reduction surgery in patients with severe emphysema. Endobronchial valves have also been used to treat patients with persistent pulmonary air leaks and those with bronchopleural fistulae. We report a case of a 61-year-old male with severe bullous emphysema. Following video-assisted thoracoscopic surgery and giant bullectomy, he had a persistent air leak. We inserted two endobronchial valves (in the lingular lobe and the anterior segment of the upper lobe) and the air leak ceased immediately. However, over the subsequent 5 months following the insertion of the endobronchial valves, the patient suffered recurrent chest infections and the endobronchial valves were found to have migrated to the orifice of the basal segment of the left lower lobe and the orifice of the basal segments of the right lower lobe. PMID:21435897

  16. Dry reforming of hydrocarbon feedstocks

    Energy Technology Data Exchange (ETDEWEB)

    Shah, Yatish T. [Norfolk State University; Gardner, Todd H. [U.S. DOE

    2014-09-25

    Developments in catalyst technology for the dry reforming of hydrocarbon feedstocks are reviewed for methane, higher hydrocarbons and alcohols. Thermodynamics, mechanisms and the kinetics of dry reforming are also reviewed. The literature on Ni catalysts, bi-metallic Ni catalysts and the role of promoters on Ni catalysts is critically evaluated. The use of noble and transitional metal catalysts for dry reforming is discussed. The application of solid oxide and metal carbide catalysts to dry reforming is also evaluated. Finally, various mechanisms for catalyst deactivation are assessed. This review also examines the various process related issues associated with dry reforming such as its application and heat optimization. Novel approaches such as supercritical dry reforming and microwave assisted dry reforming are briefly expanded upon.

  17. Hydrocarbon Rocket Technology Impact Forecasting

    Science.gov (United States)

    Stuber, Eric; Prasadh, Nishant; Edwards, Stephen; Mavris, Dimitri N.

    2012-01-01

    Ever since the Apollo program ended, the development of launch propulsion systems in the US has fallen drastically, with only two new booster engine developments, the SSME and the RS-68, occurring in the past few decades.1 In recent years, however, there has been an increased interest in pursuing more effective launch propulsion technologies in the U.S., exemplified by the NASA Office of the Chief Technologist s inclusion of Launch Propulsion Systems as the first technological area in the Space Technology Roadmaps2. One area of particular interest to both government agencies and commercial entities has been the development of hydrocarbon engines; NASA and the Air Force Research Lab3 have expressed interest in the use of hydrocarbon fuels for their respective SLS Booster and Reusable Booster System concepts, and two major commercially-developed launch vehicles SpaceX s Falcon 9 and Orbital Sciences Antares feature engines that use RP-1 kerosene fuel. Compared to engines powered by liquid hydrogen, hydrocarbon-fueled engines have a greater propellant density (usually resulting in a lighter overall engine), produce greater propulsive force, possess easier fuel handling and loading, and for reusable vehicle concepts can provide a shorter turnaround time between launches. These benefits suggest that a hydrocarbon-fueled launch vehicle would allow for a cheap and frequent means of access to space.1 However, the time and money required for the development of a new engine still presents a major challenge. Long and costly design, development, testing and evaluation (DDT&E) programs underscore the importance of identifying critical technologies and prioritizing investment efforts. Trade studies must be performed on engine concepts examining the affordability, operability, and reliability of each concept, and quantifying the impacts of proposed technologies. These studies can be performed through use of the Technology Impact Forecasting (TIF) method. The Technology Impact Forecasting method is a normative forecasting technique that allows the designer to quantify the effects of adding new technologies on a given design. This method can be used to assess and identify the necessary technological improvements needed to close the gap that exists between the current design and one that satisfies all constraints imposed on the design. The TIF methodology allows for more design knowledge to be brought to the earlier phases of the design process, making use of tools such as Quality Function Deployments, Morphological Matrices, Response Surface Methodology, and Monte Carlo Simulations.2 This increased knowledge allows for more informed decisions to be made earlier in the design process, resulting in shortened design cycle time. This paper will investigate applying the TIF method, which has been widely used in aircraft applications, to the conceptual design of a hydrocarbon rocket engine. In order to reinstate a manned presence in space, the U.S. must develop an affordable and sustainable launch capability. Hydrocarbon-fueled rockets have drawn interest from numerous major government and commercial entities because they offer a low-cost heavy-lift option that would allow for frequent launches1. However, the development of effective new hydrocarbon rockets would likely require new technologies in order to overcome certain design constraints. The use of advanced design methods, such as the TIF method, enables the designer to identify key areas in need of improvement, allowing one to dial in a proposed technology and assess its impact on the system. Through analyses such as this one, a conceptual design for a hydrocarbon-fueled vehicle that meets all imposed requirements can be achieved.

  18. Physicians' migration in Europe: an overview of the current situation

    OpenAIRE

    Amaya Carlos; García-Pérez Miguel A; Otero Ángel

    2007-01-01

    Abstract Background The migration of medical professionals as a result of the expansion of the European Union is cause for concern. But there is a significant lack of information available about this phenomenon. Methods Search of secondary databases about the presence of european doctors working abroad, through two search engines in the Internet (Google and Pubmed) and a survey of professional organisations and regulators in countries of the European Union. Results The United Kingdom has more...

  19. Migration: the trends converge.

    Science.gov (United States)

    1985-09-01

    Formerly, Australia, New Zealand, Canada, and the US have served as permanent destinations for immigrants, while Europe's migrants have moved to more northerly countries to work for a time and then returned home. From 1973-1975 Europe's recruitment of foreign workers virtually ended, although family reunion for those immigrants allowed in was encouraged. Problems resulting from this new settlement migration include low paying jobs for immigrant women, high unemployment, and inadequate education for immigrant children. Illegal migrants from Latin America and the Caribbean enter the US and Canada each year while illegal North African immigrants enter Italy, Spain, and Greece. North America, Australia, and Europe have all received political refugees from Asia and Latin America. Increasingly, these foreigners compete in the labor market rather than simply fill jobs the native workers do not want. All the receiving countries have similar policy priorities: 1) more effective ways for controlling and monitoring inflows and checking illegal immigration; 2) encouraging normal living patterns and accepting refugees; and 3) integrating permanent migrants into the host country. Europe's public immigration encouragement prior to the first oil shock, has left some countries with a labor force that is reluctant to return home. It is unlikely that Europe will welcome foreign labor again in this decade, since unemployment among young people and women is high and family reunion programs may still bring in many immigrants. Less immigration pattern change will probably occur in North America, Australia, and New Zealand since these countries' populations are still growing and wages are more flexible. Immigration, regulated by policy, and emigration, determined by market forces, now are working in the same direction and will likely reduce future migration flows. PMID:12267642

  20. Deep desulfurization of hydrocarbon fuels

    Science.gov (United States)

    Song, Chunshan (State College, PA); Ma, Xiaoliang (State College, PA); Sprague, Michael J. (Calgary, CA); Subramani, Velu (State College, PA)

    2012-04-17

    The invention relates to processes for reducing the sulfur content in hydrocarbon fuels such as gasoline, diesel fuel and jet fuel. The invention provides a method and materials for producing ultra low sulfur content transportation fuels for motor vehicles as well as for applications such as fuel cells. The materials and method of the invention may be used at ambient or elevated temperatures and at ambient or elevated pressures without the need for hydrogen.

  1. Catalytic method for synthesizing hydrocarbons

    Science.gov (United States)

    Sapienza, Richard S. (Shoreham, NY); Sansone, Michael J. (Summit, NJ); Slegeir, William A. R. (Hampton Bays, NY)

    1984-01-01

    A method for synthesizing hydrocarbons from carbon monoxide and hydrogen by contacting said gases with a slurry of a catalyst composed of palladium or platinum and cobalt supported on a solid phase is disclosed. The catalyst is prepared by heating a heterogeneous component of the palladium or platinum deposited on the solid support in a solution of cobalt carbonyl or precursors thereof. The catalyst exhibits excellent activity, stability in air, and produces highly desirable product fractions even with dilute gaseous reactants.

  2. Geologic setting for hydrocarbons in Tunisia

    Energy Technology Data Exchange (ETDEWEB)

    Schamel, S. (Univ. of South Carolina, Columbia (USA))

    1990-05-01

    Hydrocarbon habitats on the Tunisia-Sicily shelf result from the complex interplay of three factors: (1) proximity to a source of terrigenous sediments, (2) eustatic sea level changes resulting in major transgression/regression events, and (3) a varied and ever-changing structural mosaic involving successive transtensional, transpressive, and compressional tectonic phases. The stratigraphy, structure, and petroleum resources of the shelf are linked to the crustal template created during the middle Mesozoic rifting of the Tethyan margin of North Africa. Transtensional stretching and crustal fragmentation forming the Tunisia-Sicily passive margin occurred in the Late Triassic-Jurassic at the juncture of the South Saharan and Gibraltar shear zones, creating a complex array of ridges and furrows and localized pull-apart basins. During the Cretaceous and early Tertiary, the subsident block-faulted shelf was buried beneath a varied stratigraphy ranging from a thin pelagic limestone succession devoid of terrigenous components in Sicily to a considerably thicker neritic Tunisian succession composed of mixed terrigenous and carbonate strata. Differences in stratigraphic character across the shelf relate to the relative position of Sicily and Tunisia between the unstable and subsident Tethyan margin and the stable and emergent Saharn platform. Beginning in the middle Cretaceous, the region experienced localized tectonic instability expressed as transtensional faulting, crustal inversion, salt diapirism, and submarine volcanism. These events profoundly altered bathymetry and facies distribution on the shelf. As the North African continental margin subducted northward beneath the Kabyle-Calabrian accretionary complex in the late Cenozoic, the thin competent carbonate successions of Sicily responded by detaching in a series of southward migrating thrust sheets. The thrusts die out along strike in Tunisia.

  3. Hydrocarbon prospectivity in Western Greece

    Energy Technology Data Exchange (ETDEWEB)

    Maravelis, Angelos; Makrodimitras, George; Zelilidis, Avraam [Patras Univ. (Greece). Lab. of Sedimentology

    2012-06-15

    The geology of Western Greece is dominated by the most external zones of the Hellenide fold-and-thrust belt, namely the Pre-Apulian (or Paxoi) and Ionian zones. With Western Greece and Albania having undergone, in broad terms, similar geological histories, also the hydrocarbon potentials of both areas may be compared. Likewise, the hydrocarbon potential of Italy's Apulian Platform, adjoining in the westerly offshore, may serve as an analogue. Three basin types within Western Greece that deserve hydrocarbon exploration have been examined and are grouped, correlated to major tectonic features, namely foreland (Ionian thrusts' foreland basin), piggy-back (Ionian thrusts' back-arc basin) and strike-slip basins. Additionally, strike-slip basins are further subdivided into the basin north of the Borsh-Khardhiqit strike-slip fault and the Preveza basin, north of Cephalonia transfer fault. Their filling histories suggest the occurrence of Mesozoic carbonate plays and Oligocene/Miocene sandstone plays both for oil and gas.

  4. Source rock hydrocarbons. Present status

    International Nuclear Information System (INIS)

    This report first presents the characteristics of conventional oil and gas system, and the classification of liquid and gaseous non conventional hydrocarbons, with the peculiar case of coal-bed methane. The authors then describe how source rock hydrocarbons are produced: production of shale oils and gases (horizontal drilling, hydraulic fracturing, exploitation) and of coal-bed methane and coal mine methane. In the next part, they address and discuss the environmental impact of source rock hydrocarbon production: installation footprint, water resource management, drilling fluids, fracturing fluids composition, toxicity and recycling, air pollution, induced seismicity, pollutions from other exploitation and production activities. They propose an overview of the exploitation and production of source rock gas, coal-bed gas and other non conventional gases in the world. They describe the current development and discuss their economic impacts: world oil context and trends in the USA, in Canada and other countries, impacts on the North American market, on the world oil industry, on refining industries, on the world oil balance. They analyse the economic impacts of non conventional gases: development potential, stakes for the world gas trade, consequence for gas prices, development opportunities for oil companies and for the transport sector, impact on CO2 emissions, macro-economic impact in the case of the USA

  5. Africa: Setting for Human Migration

    Science.gov (United States)

    Buuba, Babacar Diop

    2007-01-01

    Analysis of African migrations can help to understand prehistoric, historical, ancient modern and contemporaneous migrations. Movements of populations were and continue to be so intense that, for some analysts, they constitute one of the dominant trends of the history and destiny of the very old continent. African and non-African states, whether…

  6. Residence, Migration, and School Progress.

    Science.gov (United States)

    Straits, Bruce C.

    1987-01-01

    Using data from the 1967 Survey of Economic Opportunity, this study investigates the effects of migration on the progress of children in school. Concludes that migration negatively affects school progress only among students with less-educated parents. (Author/JDH)

  7. Ambient aromatic hydrocarbon measurements at Welgegund, South Africa

    Directory of Open Access Journals (Sweden)

    K. Jaars

    2014-02-01

    Full Text Available Aromatic hydrocarbons are associated with direct adverse human health effects and can have negative impacts on ecosystems due to their toxicity, as well as indirect negative effects through the formation of tropospheric ozone and secondary organic aerosol that affect human health, crop production and regional climate. Measurements were conducted at the Welgegund measurement station (South Africa that is considered to be a regionally representative background site. However, the site is occasionally impacted by plumes from major anthropogenic source regions in the interior of South Africa, which include the western Bushveld Igneous Complex (e.g. platinum, base metal and ferrochrome smelters, the eastern Bushveld Igneous Complex (platinum and ferrochrome smelters, the Johannesburg–Pretoria metropolitan conurbation (>10 million people, the Vaal Triangle (e.g. petrochemical and pyrometallurgical industries, the Mpumalanga Highveld (e.g. coal-fired power plants and petrochemical industry and also a region of anti-cyclonic recirculation of air mass over the interior of South Africa. The aromatic hydrocarbon measurements were conducted with an automated sampler on Tenax-TA and Carbopack-B adsorbent tubes with heated inlet for one year. Samples were collected twice a week for two hours during daytime and two hours during night-time. A thermal desorption unit, connected to a gas chromatograph and a mass selective detector was used for sample preparation and analysis. Results indicated that the monthly median total aromatic hydrocarbon concentrations ranged between 0.01 to 3.1 ppb. Benzene levels did not exceed local air quality standards. Toluene was the most abundant species, with an annual median concentration of 0.63 ppb. No statistically significant differences in the concentrations measured during daytime and night-time were found and no distinct seasonal patterns were observed. Air mass back trajectory analysis proved that the lack of seasonal cycles could be attributed to patterns determining the origin of the air masses sampled. Aromatic hydrocarbon concentrations were in general significantly higher in air masses that passed over anthropocentrically impacted regions. Interspecies correlations and ratios gave some indications of the possible sources for the different aromatic hydrocarbons in the source regions defined in the paper. The highest contribution of aromatic hydrocarbon concentrations to ozone formation potential was also observed in plumes passing over anthropocentrically impacted regions.

  8. Software Engineering Challenges of Migration Projects

    Directory of Open Access Journals (Sweden)

    S.Geetha

    2012-03-01

    Full Text Available Organisations often face the challenges of migration from legacy systems to new target systems. Such migration efforts represent a complex engineering problem. This paper describes migration planning, identifies influencing factors, outlines a set of migration planning activities and offers a set of guidelines for the migration planning

  9. Software Engineering Challenges of Migration Projects

    OpenAIRE

    S.Geetha; Dr.Alagaramy

    2012-01-01

    Organisations often face the challenges of migration from legacy systems to new target systems. Such migration efforts represent a complex engineering problem. This paper describes migration planning, identifies influencing factors, outlines a set of migration planning activities and offers a set of guidelines for the migration planning

  10. Seismic chimneys in the Southern Viking Graben - Implications for palaeo fluid migration and overpressure evolution

    Science.gov (United States)

    Karstens, Jens; Berndt, Christian

    2015-02-01

    Detailed understanding of natural fluid migration systems is essential to minimize risks during hydrocarbon exploration and to evaluate the long-term efficiency of the subsurface storage of waste water and gas from hydrocarbon production as well as CO2. The Southern Viking Graben (SVG) hosts numerous focused fluid flow structures in the shallow (SVG hosts more than 46 large-scale vertical chimney structures, which can be divided in three categories implying different formation processes. Our analysis reveals that seal-weakening, formation-wide overpressure and the presence of free gas are required to initiate the formation of vertical fluid conduits in the SVG. The presence of numerous vertical fluid conduits implies inter-stratigraphic hydraulic connectivity, which significantly affects the migration of fluids in the subsurface. Chimney structures are important for understanding the transfer of pore pressure anomalies to the shallow parts of the basin.

  11. Anomalous dynamics of cell migration

    CERN Document Server

    Dieterich, Peter; Preuss, Roland; Schwab, Albrecht; 10.1073/pnas.0707603105

    2009-01-01

    Cell movement, for example during embryogenesis or tumor metastasis, is a complex dynamical process resulting from an intricate interplay of multiple components of the cellular migration machinery. At first sight, the paths of migrating cells resemble those of thermally driven Brownian particles. However, cell migration is an active biological process putting a characterization in terms of normal Brownian motion into question. By analyzing the trajectories of wildtype and mutated epithelial (MDCK-F) cells we show experimentally that anomalous dynamics characterizes cell migration. A superdiffusive increase of the mean squared displacement, non-Gaussian spatial probability distributions, and power-law decays of the velocity autocorrelations are the basis for this interpretation. Almost all results can be explained with a fractional Klein- Kramers equation allowing the quantitative classification of cell migration by a few parameters. Thereby it discloses the influence and relative importance of individual comp...

  12. Geometric control of cell migration.

    Science.gov (United States)

    Chen, Bo; Kumar, Girish; Co, Carlos C; Ho, Chia-Chi

    2013-01-01

    Morphological polarization involving changes in cell shape and redistribution of cellular signaling machinery, initiate the migration of mammalian cells. Golgi complex typically localizes in front of the nucleus, and this frontwards polarization has been proposed to be involved in directional migration. However, the sequence of events remains unresolved. Does Golgi polarization precede directional migration or vice-versa? We address this question by constraining cells to specific areas and shapes then tracking their motile behavior and the spatio-temporal distribution of Golgi apparatus upon release. Results show that while the position of the Golgi complex depends on the cell geometry, the subcellular localization of the Golgi complex does not define the cell's leading edge. Cells constrained within elongated geometries exhibit polarized extension of lamellipodia and upon release, migrate preferentially along the long axis of the cell. Minimally constrained cells released from larger areas however, exhibit retarded migration regardless of lamellipodia protrusion activity. PMID:24089214

  13. Brine migration: a summary report

    International Nuclear Information System (INIS)

    As defined in this report, brine migration is the movement toward a heat source of the water trapped in rock salt. This phenomenon is of interest because the disposal of heat-producing radioactive wastes can trigger brine migration. Contact between the brine and the waste packages could lead to such undesirable interactions as corrosion of the canister or even migration of the radionuclides. This report summarizes a Sandia National Laboratories program to characterize brine migration. Based on this program and on the work of others, we conclude that brine migration is not a significant problem. The quantities of water (less than 20 L/waste canister in 1000 yr) are too small for concern

  14. Mécanismes de migration des radionucléides d'un stockage de déchets radioactifs dans l'argile vers la surface

    Science.gov (United States)

    de Marsily, Ghislain; Gonçalvès, Julio; Violette, Sophie; Castro, Maria-Clara

    2002-10-01

    This article is a critical review of the current understanding of migration processes of solutes in clay. The major migration mechanisms are examined: advection through compaction, thermal convection, migration by hydrocarbon expulsion, gravitational flow, osmosis, molecular diffusion, hydrodynamic dispersion. Examples are taken from the Callovo-Oxfordian clays of the Paris basin in the Meuse/Haute Marne area, near Bure, where France is studying the feasibility of a potential nuclear waste disposal facility. Recent work on the helium distribution in the aquifers of the Paris Basin confirms the importance of molecular diffusion for solute transport in clays. Migration in aquifers is also described, and the major causes of uncertainties for solute migration are discussed. To cite this article: G. de Marsily et al., C. R. Physique 3 (2002) 945-959.

  15. Experimental investigation of hydrocarbon formation and transformation under Earth's upper mantle conditions

    Energy Technology Data Exchange (ETDEWEB)

    Kolesnikov, Anton

    2010-12-15

    The theory of the abyssal abiotic petroleum origin considers oil and natural gas to be generated in the Earth's upper mantle. Hydrocarbons migrate further through the deep faults into the Earth's crust, where they can form oil and gas deposits in any kind of rock in any kind of structural position. Until recently one of the main obstacles for further development of this theory has been the lack of the data covering processes of generation and transformations of hydrocarbons. Experimental data, presented in this thesis, confirms the possibility of hydrocarbons formation from mantle inorganic compounds (water, Fe, CaCO{sub 3} or graphite) at temperature and pressure of the upper mantle (1500 K and 5 GPa). Experiments were carried out in CONAC high pressure device and multianvil apparatus BARS. Compositions of received gas mixtures were similar to natural gas. Quantity of hydrocarbons depended on the cooling regime of reaction mixture under pressure. Slow cooling favored higher quantity. We found that donor of carbon (CaCO{sub 3} or graphite) determines formation of 'dry' (methane-rich) gas or 'wet' (light hydrocarbons-rich) gas. Experiments in laser-heated diamond anvil cells showed that methane and ethane partially react under upper mantle thermobaric conditions (2-5 GPa, 1000-1500 K) to form mixture of hydrocarbons: methane, ethane, propane and n-butane - main compounds of natural gas. Similarity of final product mixture obtained from methane and ethane means thermodynamic stability of hydrocarbons in the thermobaric conditions of the upper mantle and equilibrium character of the observed processes

  16. Saturated hydrocarbons occluded inside asphaltene structures and their geochemical significance, as exemplified by two Venezuelan oils

    Energy Technology Data Exchange (ETDEWEB)

    Zewen Liao [Chinese Academy of Sciences, Guangzhou (China). Inst. of Geochemistry; Lab. des Fluides Complexes, Pau (France); Ansong Geng; Yaxue Zhang [Chinese Academy of Sciences, Guangzhou (China). Inst. of Geochemistry; Graciaa, A.; Creux, P. [Lab. des Fluides Complexes, Pau (France); Chrostowska, A. [Pau Univ. (France). Lab. de Chimie Theorique et Physico-Chimie Moleculaire

    2006-03-15

    Inside asphaltene aggregates in crude oils, the adsorbed hydrocarbons exist in the packed periphery while the occluded hydrocarbons exist inside the core of the asphaltene structures. Occluded hydrocarbons may be well protected from secondary alteration events in the reservoir due to the colloidal nature of asphaltenes, and can be representative of older oil than the reservoir oil, and so may be very useful for reservoir geochemical studies. In this work, two Venezuelan oils derived from the same source rock have been studied. The results indicate that the oxidative reagent H{sub 2}O{sub 2}/CH{sub 3}COOH can release the occluded hydrocarbons from the asphaltene aggregates, making it possible to selectively study these compounds without interference from the moieties that are covalent-bonded to the asphaltene structures. In order to obtain the precise information from the occluded hydrocarbons, prior to the oxidation processes, acetone extraction of the asphaltenes has been applied to rule out interferences from the adsorbed compounds. Furthermore, pyrolysis of asphaltenes has been performed for comparison with the occluded saturated hydrocarbons. From the oxidation products of asphaltenes from these two crude oils, the saturated hydrocarbons (from the occluded original oil) have very similar distributions, including terpanes and steranes, and almost the same biomarker parameters. These results are in accord with the fact that oil from the same source rock was occluded by both Ven1 and Ven2 asphaltenes. The geochemical information obtained from the occluded saturated hydrocarbons suggests that the source rock depositional setting for these two crude oil samples was an anoxic, hypersaline/evaporitic environment. (author)

  17. Influences of environmental cues, migration history and habitat familiarity on partial migration

    DEFF Research Database (Denmark)

    Skov, Christian; Aarestrup, Kim

    2010-01-01

    The factors that drive partial migration in organisms are not fully understood. Roach (Rutilus rutilus), a freshwater fish, engage in partial migration where parts of populations switch between summer habitats in lakes and winter habitats in connected streams. To test if the partial migration trait is phenotypically plastic or has genetic components, we translocated roach from 2 populations with different opportunities for migration to a lake with migration opportunity, containing a local roach population. This enabled monitoring of partial migration of fish in 3 different situations: 1) previous opportunity for migration, migrating in a familiar environment (the local population); 2) previous opportunity for migration, migrating in an unfamiliar environment; and 3) no previous opportunity for seasonal migration, migrating in an unfamiliar environment. In addition, we evaluated the migration patterns of roach in the lake with migration opportunity where from group 2 fish were translocated. Directional migration in and out of the lakes was monitored using Passive Integrated Transponder technology. Translocated fish with previous migration opportunity showed migration patterns more similar to local fish than to their home lake population, and individuals translocated from the lake without migration opportunity migrated when given the opportunity, suggesting that partial migration is phenotypically plastic and triggered by lake-specific environmental cues. We found temperature to be a proximate cue for migration decisions. Individuals without previous migration opportunity migrated at a lower proportion and with different small-scale migration patterns, suggesting that also genetic components are involved in the expression of the partial migration trait.

  18. DNAPL migration in a coastal plain aquifer

    International Nuclear Information System (INIS)

    Soil and ground water at the Dover Gas Light Superfund Site, a former manufactured gas plant (1859 to 1948), are contaminated with polynuclear aromatic hydrocarbons and volatile organic compounds. Contaminants of concern include light aromatics, such as benzene, toluene, ethylbenzene, and xylenes (BTEX), and heavy aromatics, including naphthalene, acenaphthylene, phenanthrene, and benzo(a)pyrene. Although ground-water contaminant levels are elevated near the site, only naphthalene and acenaphthylene are present within an order of magnitude of their solubility limits, indicating the possibility of dense non-aqueous phase liquids (DNAPL) in the subsurface. The unconfined Columbia Aquifer, which is characterized by interfingering and discontinuous sand, silt, and clay Coastal Plain deposits, overlies a clay aquitard at a depth of 60 feet. The ground water beneath the intermediate clay horizon exhibited little or no contamination, even immediately downgradient from the site. The relationship between the more permeable granular sand horizons and the less permeable interfingering clay zones controls the migration of both the aqueous-phase contamination and the DNAPL. A detailed horizontal and vertical characterization of the subsurface stratigraphy was critical to the accurate interpretation of the extent and magnitude of contamination and the identification and delineation of DNAPL zones

  19. Migration behaviour of iodine in nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Hocking, W.H.; Verrall, R.A.; Muir, I.J

    2001-07-01

    A novel out-reactor method has been further developed for investigating the migration behaviour of fission products in UO{sub 2} nuclear fuel, which allows the effects of thermal diffusion. radiation damage and local segregation to be independently assessed. Tailored concentration profiles of any desired species are first created in the near-surface region of polished samples by ion implantation. The impact of either thermal annealing or simulated fission is then precisely determined by depth profiling with high-performance secondary ion mass spectrometry (SIMS). Comparison of iodine migration in U0{sub 2} wafers that had been ion-implanted to fluences spanning five orders of magnitude has revealed subtle radiation-damage effects and a pronounced concentration dependence for thermal diffusion. At concentrations above {approx}10{sup 16} atoms/cm{sup 3} much of the iodine became trapped, likely in microscopic bubbles. True thermal diffusion coefficients for iodine in polycrystalline U0{sub 2} have been derived by modelling the low-fluence data. (author)

  20. Grounding a theory of African migration in recent data on Ghana.

    Science.gov (United States)

    Achanfuo-yeboah, D

    1993-06-01

    This article discusses the development of a single theory of migration in Africa, which accounts for social, economic, cultural, psychological, and demographic factors. Prior migration literature refers to many countries in Africa. The empirical test in this paper is based on Ghana and data for 1960, 1970, and 1984. Ghana is described as having rapid population growth and urbanization reaching 12.5 million in 1984. The economy is based on agriculture, mining, and manufacturing. Education is available for free through the secondary school level (since 1965). The general theory of migration holds that the nature, intensity, direction, and patterns of migration are shaped by social, cultural, economic, and political developments. Sociocultural developments, or nonagricultural occupations and educational resources, may influence the flow of migration to urban areas. The regression model shows that 70% of the variance in net migration is explained by education, economic activity, and population growth. Education determines the direction and intensity of migration. A unit value of education causes a change of 0.251952 in the value of net migration. Norms, values, and beliefs are affected by educational and employment opportunities and are influenced by factors such as kinship, clan, language, beliefs, and religion. Economic infrastructure, industrialization, employment opportunities, and increased wages and salaries exert a pull on migrants. During the 1960s, Ghana attracted migrants from Nigeria. During the 1970s and 1980s, the reverse occurred. Migrants tend to move based on expectations of higher wages and better employment. In a bivariate relationship, economic activity explains 62% of the variance in migration. A unit change in the value of economic activity leads to a change of 1.379382 in the value of net migration. The literature emphasizes rural-urban flows, but migration in Gwan state in Cameroon and Udo state in Nigeria reflects the prevalence of rural-to-rural migration. The study of migration in Africa must consider a multivariate approach. PMID:12179894

  1. Chronic kidney disease after vesico-vaginal stone formation around a migrated intrauterine device

    OpenAIRE

    Karsmakers, R; Weis-Potters, A E; Buijs, Guido; Joustra, E B

    2010-01-01

    Although the intrauterine device (IUD) seems a reliable and relatively safe method of contraception, it may cause serious complications. A rare complication is uterus perforation. Intravesical migration and secondary calculus formation is exceptionally uncommon. The authors report on a 75-year-old woman in whom a ‘forgotten’ migrated IUD resulted in vesico-vaginal fistula formation and chronic kidney disease, 39 years after insertion.

  2. Survival of Trojan-Type Companions of Neptune During Primordial Planet Migration

    OpenAIRE

    Kortenkamp, Steve; Malhotra, Renu; Michtchenko, Tatiana

    2003-01-01

    We investigate the survivability of Trojan-type companions of Neptune during primordial radial migration of the giant planets Jupiter, Saturn, Uranus, and Neptune. Loss of Neptune Trojans during planetary migration is not a random diffusion process. Rather, losses occur almost exclusively during discrete episodes when Trojan particles are swept by secondary resonances associated with mean-motion commensurabilities of Uranus with Neptune. The single greatest episode of loss e...

  3. Late-Onset Screw Migration into Iliac Vessels 21 years after Hip Arthrodesis

    OpenAIRE

    Taishi Hirai; Yutaka Inaba; Naomi Kobayashi; Shu Takakagawa; Yohei Yukizawa; Hiroyuki Ike; Tomoyuki Saito

    2014-01-01

    Iatrogenic injuries to the vascular system are a rare but serious complication of hip surgery. We report a case of an 83-year-old man who presented with intrapelvic migration of a screw into the space between the external iliac artery and vein 21 years after hip arthrodesis. The patient was treated with laparotomy, and the damaged artery was excised and sutured. This is the first case of a late vascular complication secondary to screw migration after hip arthrodesis.

  4. Basic neutronics. Neutrons migration

    International Nuclear Information System (INIS)

    This article presents the basic neutronics necessary for the understanding of the operation of the different types of nuclear reactors: 1 - introduction to neutronics: principle of fission chain reactions, fast neutron reactors and thermal neutron reactors, capture, neutron status, variations with the reactor lattices; 2 - Boltzmann equation: neutrons population, neutrons migration, characterization of neutrons population and reactions, integral form of the Boltzmann equation, integral-differential form, equivalence between the two forms; 3 - reactor kinetics: fast neutrons and delayed neutrons, kinetic equations in punctual model, Nordheim equation, reactivity jumps, reactivity ramp; 4 - diffusion equation: local neutron status, Fick's law, diffusion equation, initial, boundary and interface conditions, nuclei in infinite and homogenous medium, some examples of solutions, developments in Eigenmodes; 5 - one-group theory: equation of the 'one-group - diffusion' theory, critical condition of the naked and homogenous reactor, critical condition of a reactor with reflectors, generalizations; 6 - neutrons moderation: different moderation mechanisms, elastic shock laws, moderation equation, some examples of solutions; 7 - resonance absorption of neutrons: advantage of the discontinuous moderation character, advantage of an heterogenous disposition, classical formula of the anti-trap factor in homogenous and heterogenous situation; 8 - neutrons thermalization: notions of thermalization mechanisms, thermalization equation, Maxwell spectrum, real spectrum, classical formula of the thermal utilisation factor, classical formula of the reproduction factor, moderation optimum. (J.S.)

  5. Before the Bonanza:Hydrocarbons in Greenland

    OpenAIRE

    Meinild, Ebbe Dam

    2010-01-01

    The issue of Greenlandic hydrocarbons gradually moved towards the centre of the creation of autonomous Greenland. Hydrocarbons in Greenland and the Greenlandic nation were co-produced in the same process. Thus, when hydrocarbons were connected to an ecological modernisation it allowed the newly formed Home Rule administration, in a joint Danish-Greenlandic effort, to adopt this, not only as a road to independence, but as something giving credibility to Greenland as a distinct society.

  6. Volatile hydrocarbons inhibit methanogenic crude oil degradation

    OpenAIRE

    AngelaSherry; RussellJGrant

    2014-01-01

    Methanogenic degradation of crude oil in subsurface sediments occurs slowly, but without the need for exogenous electron acceptors, is sustained for long periods and has enormous economic and environmental consequences. Here we show that volatile hydrocarbons are inhibitory to methanogenic oil biodegradation by comparing degradation of an artificially weathered crude oil with volatile hydrocarbons removed, with the same oil that was not weathered. Volatile hydrocarbons (nC5-nC10, methylcyclo...

  7. HYDROCARBON AND SULFUR SENSORS FOR SOFC SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    A.M. Azad; Chris Holt; Todd Lesousky; Scott Swartz

    2003-11-01

    The following report summarizes work conducted during the Phase I program Hydrocarbon and Sulfur Sensors for SOFC Systems under contract No. DE-FC26-02NT41576. For the SOFC application, sensors are required to monitor hydrocarbons and sulfur in order to increase the operation life of SOFC components. This report discusses the development of two such sensors, one based on thick film approach for sulfur monitoring and the second galvanic based for hydrocarbon monitoring.

  8. Migration of dispersive GPR data

    Science.gov (United States)

    Powers, M.H.; Oden, C.P.

    2004-01-01

    Electrical conductivity and dielectric and magnetic relaxation phenomena cause electromagnetic propagation to be dispersive in earth materials. Both velocity and attenuation may vary with frequency, depending on the frequency content of the propagating energy and the nature of the relaxation phenomena. A minor amount of velocity dispersion is associated with high attenuation. For this reason, measuring effects of velocity dispersion in ground penetrating radar (GPR) data is difficult. With a dispersive forward model, GPR responses to propagation through materials with known frequency-dependent properties have been created. These responses are used as test data for migration algorithms that have been modified to handle specific aspects of dispersive media. When either Stolt or Gazdag migration methods are modified to correct for just velocity dispersion, the results are little changed from standard migration. For nondispersive propagating wavefield data, like deep seismic, ensuring correct phase summation in a migration algorithm is more important than correctly handling amplitude. However, the results of migrating model responses to dispersive media with modified algorithms indicate that, in this case, correcting for frequency-dependent amplitude loss has a much greater effect on the result than correcting for proper phase summation. A modified migration is only effective when it includes attenuation recovery, performing deconvolution and migration simultaneously.

  9. A study of hydrocarbon contamination in glacial till

    International Nuclear Information System (INIS)

    A pre-acquisition environmental assessment was conducted for an Alberta site in a commercial district, leading to the detection of petroleum hydrocarbons, characterized as diesel fuel, in several boreholes. A ground penetrating radar scan led to the removal of a 1000 gallon and a 10,000 gallon tank from the site. It was determined that leakage from two 5000 gallon tanks previously installed was responsible for the hydrocarbon contamination. An extensive site investigation revealed that leaked diesel products had migrated downward and spread laterally within a sandy silt layer of a lacustrine deposit and inter-till sand pockets. In-situ conductivity tests for the free product bearing soils were carried out. The area of contamination was estimated to be greater than 7000 m3 at depths extending between 4 and 15 m below grade. A series of field recovery tests were conducted to assess the recovery characteristics and flow dynamics of the free product bearing soil deposits, with ca 3700 liters of diesel product removed over a six month period. A pneumatic pulse pump system was used to implement a well recovery program, and ca 600 liters of product was removed within a month period. Once product removal is completed, the site will be developed with an underground car-park with contaminated soils removed during construction. 7 refs., 9 figs

  10. Hydrocarbon potential of Altiplano and northern Subandean, Bolivia

    Energy Technology Data Exchange (ETDEWEB)

    Edman, J.D.; Kirkpatrick, J.R.; Lindsey, D.D.; Lowell, J.D.; Cirbian, M.; Lopez, M.

    1989-03-01

    Seismic, stratigraphic, structural, and geochemical data from the Altiplano, northern Subandean, and northern plains of Bolivia were interpreted in order to evaluate the exploration potential of each province. Identification of three possible source rock intervals, primarily the Devonian and secondarily the Permian and Cretaceous, was used as the basis for recognizing active hydrocarbon systems. For those areas containing source intervals, their analysis revealed that possible reservoir and seal units range in age from Paleozoic to Tertiary; the majority of structures, however, are Eocene or younger. With these general concepts in mind, traps were identified in all three sedimentary provinces. In the northern Altiplano, the most prospective area is along the eastern margin near a southwest and west-vergent thrust belt where hanging-wall anticlines and a warped Eocene-Oligocene(.) unconformity surface form the most likely potential traps. In the central and southern Altiplano, both thrust-related and wrench-related structures present possible exploration targets. In the northern Subandean and Beni plains north of the Isiboro-Chapare area, traps can be classified into two broad groups. First, there are a wide variety of structural traps within the northern Subandean thrust belt, the most attractive of which are footwall structures that have been shielded from surface flushing by hanging-wall strata. Second, in the plains just northeast of the thrust belt, hydrocarbons sourced from the remnant Paleozoic basin may have migrated onto the Isarsama and Madidi highs.

  11. Migration in the Soviet Successor States

    OpenAIRE

    Locher, Lilo

    2002-01-01

    This paper analyzes the migration behavior of ethnic groups in the former Soviet Un-ion (FSU) from 1989 to 1999. The two main migration movements have been return migration of ethnic groups to their titular nation and migration of all ethnic groups to the Russian Federation. Using factor analysis, we are able to disentangle the effects of economic wealth, growth, and political reforms on migration behavior. Ethnic sorting is found to be the major determinant of migration, which can explain bo...

  12. Labour Migration and Network Effects in Moldova

    OpenAIRE

    Andersson, Lisa

    2008-01-01

    This study investigates the impact of migration networks on the decision to migrate in Moldova. Using a recent cross-sectional household survey with extensive migration information I am able to disaggregate the migration networks according to kinship and further investigate the impact of different kinds of networks. The results show that migration networks have a significant positive impact on the decision to migrate, whereas the results do not reveal any conclusive evidence that certain kins...

  13. Population commission discusses international migration.

    Science.gov (United States)

    1997-01-01

    At the 30th session of the Commission on Population and Development during February 24-28, 1997, international migration was the main topic, with special linkages between migration and development and on gender issues and the family. New and emerging issues were also considered. Members stressed the need for more reliable data on migration, the direction of migrants flows, and the characteristics of migrants. The Commission requested a task force on basic social services to hold a technical symposium of experts on international migration in 1998. Its chair, Dr. Nafis Sadik, said that migration issues should based on the reality of choice not on coercive measures or quotas. Almost half of the migrants globally are women. The Commission was given a new impetus by the International Conference on Population and Development held at Cairo in 1994. Migration pressures intensified in the second half of the 1980s and in the early 1990s, creating areas of concern: the negative impact of short-term migration on working conditions in host countries; migration pressures emanating from climatic change; the protection of migrant women and their children; the right of receiving countries to regulate access to their territory; the adverse consequences of forced migration; the situation of persons whose asylum claims have been rejected; the trafficking in women and children, prostitution and coercive adoption; and the sudden and massive arrival of refugees in need of international protection. The 1998 session of the Commission will feature the theme of health and mortality, with special emphasis on the linkages between health and development and on gender and age. PMID:12292475

  14. Detection of hydrocarbons in irradiated foods

    International Nuclear Information System (INIS)

    The hydrocarbon method for the detection of irradiated foods is now recognized as the international technique. This method is based on radiolysis of fatty acids in food to give hydrocarbons. In order to expand this technique's application, ten foods (butter, cheese, chicken, pork, beef, tuna, dry shrimp, avocado, papaya, and mango) were irradiated in the range from 0.5 to 10 kGy and the hydrocarbons in them were detected. Recoveries of the hydrocarbons from most foods were acceptable (38-128%). Some hydrocarbons were found in non-irradiated foods, particularly, in butter, cheese, tuna, and shrimp. Seven irradiated foods, butter, cheese, chicken, beef, pork, tuna, dry shrimp, and avocado were detectable at their practical doses by measuring the appropriate marker hydrocarbons. In most case, marker hydrocarbon will be 1,7-hexadecadiene. However, the marker hydrocarbons produced only in irradiated foods varied from food to food; therefore, it is necessary to check a specific irradiated food for marker hydrocarbons. On the other hand, two irradiated foods (papaya and mango which were irradiated at their practical doses) were difficult to distinguish from non-irradiated foods using this method. (author)

  15. Nox reduction system utilizing pulsed hydrocarbon injection

    Science.gov (United States)

    Brusasco, Raymond M. (Livermore, CA); Penetrante, Bernardino M. (San Ramon, CA); Vogtlin, George E. (Fremont, CA); Merritt, Bernard T. (Livermore, CA)

    2001-01-01

    Hydrocarbon co-reductants, such as diesel fuel, are added by pulsed injection to internal combustion engine exhaust to reduce exhaust NO.sub.x to N.sub.2 in the presence of a catalyst. Exhaust NO.sub.x reduction of at least 50% in the emissions is achieved with the addition of less than 5% fuel as a source of the hydrocarbon co-reductants. By means of pulsing the hydrocarbon flow, the amount of pulsed hydrocarbon vapor (itself a pollutant) can be minimized relative to the amount of NO.sub.x species removed.

  16. Detection of hydrocarbons in irradiated foods

    Energy Technology Data Exchange (ETDEWEB)

    Miyahara, Makoto; Maitani, Tamio [National Inst. of Health Sciences, Tokyo (Japan); Saito, Akiko; Kamimura, Tomomi; Nagasawa, Taeko [Kitasato Univ., Sagamihara, Kanagawa (Japan). School of Allied Health Sciences; Kobayashi, Yasuo; Ito, Hitoshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Establishment

    2003-06-01

    The hydrocarbon method for the detection of irradiated foods is now recognized as the international technique. This method is based on radiolysis of fatty acids in food to give hydrocarbons. In order to expand this technique's application, ten foods (butter, cheese, chicken, pork, beef, tuna, dry shrimp, avocado, papaya, and mango) were irradiated in the range from 0.5 to 10 kGy and the hydrocarbons in them were detected. Recoveries of the hydrocarbons from most foods were acceptable (38-128%). Some hydrocarbons were found in non-irradiated foods, particularly, in butter, cheese, tuna, and shrimp. Seven irradiated foods, butter, cheese, chicken, beef, pork, tuna, dry shrimp, and avocado were detectable at their practical doses by measuring the appropriate marker hydrocarbons. In most case, marker hydrocarbon will be 1,7-hexadecadiene. However, the marker hydrocarbons produced only in irradiated foods varied from food to food; therefore, it is necessary to check a specific irradiated food for marker hydrocarbons. On the other hand, two irradiated foods (papaya and mango which were irradiated at their practical doses) were difficult to distinguish from non-irradiated foods using this method. (author)

  17. Demetallization of hydrocarbon containing feed streams

    International Nuclear Information System (INIS)

    This patent describes how metals contained in a hydrocarbon containing feed stream are removed by contacting the hydrocarbon containing feed stream under suitable demetallization conditions with hydrogen and a catalyst composition comprising zirconium phosphate, cobalt phosphate and iron phosphate. The life and activity of the catalyst composition may be increased by introducing a decomposable metal compound selected from the group consisting of the metals of Group V-B, Group VI-B, Group VII-B and Group VIII of the Periodic Table into the hydrocarbon containing feed stream prior to contacting the hydrocarbon containing feed stream with the catalyst composition

  18. Migration and the Wage Curve:

    DEFF Research Database (Denmark)

    Brücker, Herbert; Jahn, Elke J.

      Based on a wage curve approach we examine the labor market effects of migration in Germany. The wage curve relies on the assumption that wages respond to a change in the unemployment rate, albeit imperfectly. This allows one to derive the wage and employment effects of migration simultaneously in...... with a vocational degree. The wage and employment effects of migration are moderate: a 1 percent increase in the German labor force through immigration increases the aggregate unemployment rate by less than 0.1 percentage points and reduces average wages by less 0.1 percent. While native workers...... benefit from increased wages and lower unemployment, foreign workers are adversely affected....

  19. Documentation of Active Directory Migration

    OpenAIRE

    Taskila, Kalle

    2015-01-01

    The subject of this thesis is to prepare a document of the Active Directory migration for a case company. This thesis was commissioned by a medium sized company in Oulu region. Their domain has hundreds of users and computers in their Active Directory which had to be moved to an entirely new domain which has a recent Window Server 2012 R2 operating system. The migration was set to take place in November 2015, but unfortunately migration was delayed multiple times because of other projects tha...

  20. Rural Urban Migration: Their Consequence

    OpenAIRE

    Shrimant; Khan, A. G.

    2012-01-01

    Urban migration is one of the most prevalent types of human movement. The study of the process of rural to urban migration and its biological effects is important for four reasons_ First, it entails movement into a habill: and an ecological niche—the city—that is evolutionally ne'e' for our species. Secondly, it is the most common type migration that has occurred in all periods of recorded history. Thirdly. It is occurring more rapidly today than ever before, especially in the least developed...

  1. Radial Migration in Spiral Galaxies

    CERN Document Server

    Roškar, R

    2014-01-01

    The redistribution of stars in galactic disks is an important aspect of disk galaxy evolution. Stars that efficiently migrate in such a way that does not also appreciably heat their orbits can drastically affect the stellar populations observed today and therefore influence constraints derived from such observations. Unfortunately, while the theoretical understanding of the migration process is becoming increasingly robust, there are currently few specific observable predictions. As a result, we do not yet have a clear handle on whether the process has been important for the Milky Way in the past or how to constrain it. I discuss some of the expected qualitative outcomes of migration as well as some current controversies.

  2. Full wavefield migration: utilization of multiples in seismic migration:

    OpenAIRE

    Berkhout, A.J.; Verschuur, D.J.

    2012-01-01

    The next generation migration technology considers multiple scattering as vital information, allowing the industry to generate significantly better images of the subsurface. The proposed full wavefield algorithm (FWM) makes use of two-way wave theory that is formulated in terms of one-way wavefields. We show that the current migration algorithms for primary reflections can be easily extended to handle multiple scattering as well

  3. Commercial valuation of hydrocarbon resources

    International Nuclear Information System (INIS)

    A practical business process is described which enables all categories of hydrocarbon resources to be valued in a commercially consistent manner. The benefits of the process are increased if there is a transparent corporate strategic plan which can be used to test the value of a resource against a desired portfolio, described quantitatively in terms of value and risk. Individual opportunities for both acquisition and disposal can then be measured against an assessed ''Corporate preference profile'' and pursued with increased confidence in the overall fit

  4. Applied bioremediation of petroleum hydrocarbons

    International Nuclear Information System (INIS)

    This volume is part of a ten volume set of papers derived from the Third International In Situ and On-Site Bioreclamation Symposium which was held in San Diego, California, in April 1995. The purpose of the conference was to provide a multidisciplinary forum for exchange of state-of-the-art information on bioremediation. The papers in this volume focus on petroleum hydrocarbon bioremediation, with an emphasis on pilot-scale and field-scale applications. Individual papers have been processed separately for inclusion in the appropriate data bases

  5. Exploring the factors influencing the cloud computing adoption: a systematic study on cloud migration.

    Science.gov (United States)

    Rai, Rashmi; Sahoo, Gadadhar; Mehfuz, Shabana

    2015-01-01

    Today, most of the organizations trust on their age old legacy applications, to support their business-critical systems. However, there are several critical concerns, as maintainability and scalability issues, associated with the legacy system. In this background, cloud services offer a more agile and cost effective platform, to support business applications and IT infrastructure. As the adoption of cloud services has been increasing recently and so has been the academic research in cloud migration. However, there is a genuine need of secondary study to further strengthen this research. The primary objective of this paper is to scientifically and systematically identify, categorize and compare the existing research work in the area of legacy to cloud migration. The paper has also endeavored to consolidate the research on Security issues, which is prime factor hindering the adoption of cloud through classifying the studies on secure cloud migration. SLR (Systematic Literature Review) of thirty selected papers, published from 2009 to 2014 was conducted to properly understand the nuances of the security framework. To categorize the selected studies, authors have proposed a conceptual model for cloud migration which has resulted in a resource base of existing solutions for cloud migration. This study concludes that cloud migration research is in seminal stage but simultaneously it is also evolving and maturing, with increasing participation from academics and industry alike. The paper also identifies the need for a secure migration model, which can fortify organization's trust into cloud migration and facilitate necessary tool support to automate the migration process. PMID:25977891

  6. Restructuring of the labour market and the role of third world migrations in Europe.

    Science.gov (United States)

    Pugliese, E

    1993-10-01

    "This paper is an analysis of the way in which the changes in the labour market and in the occupational structure in Europe affect the situation and the role of Third World migrants." Changes in European labor migration patterns since the 1960s are first analyzed. The author notes that "intra-European migrations were industrial migrations because manufacturing and building industries were the most important and growing economic activities....Present-day migrations are postindustrial migrations. Immigrants work mostly in service activities and not infrequently in the informal economy. In any case migrant workers are located in the secondary labour market. The picture is made more complex by the fact than many immigrants are alegal or illegal because of the restrictive immigration policies in European countries." PMID:12289810

  7. Data Migration Across The Clouds

    Directory of Open Access Journals (Sweden)

    Prashant Pant,

    2013-05-01

    Full Text Available Having an effective and efficient strategy for optimizing long distance data migration is essential for every data center. With the ever increasing demands for the IT needs of businesses it is also important for data centers to deliver data migration cost effectively especially when faced with the demands from remote office back up, outsourcing, data center movers and cloud computing. Data management and migration are important research challenges of novel Cloud environments. While moving data among different geographical domains, it is important to lower the transmission cost for performance purposes. Efficient scheduling methods allow us to manage data transmissions with lower number of steps and shorter transmission time. In previous research efforts, several methods have been proposed in literature in order to manage data and minimize transmission cost for the case of Single Cluster environments. This paper Explores the issues and method of Data Migration across the Clouds

  8. The migration challenge for PAYG.

    Czech Academy of Sciences Publication Activity Database

    Aslanyan, Gurgen

    2014-01-01

    Ro?. 27, ?. 4 (2014), s. 1023-1038. ISSN 0933-1433 Institutional support: PRVOUK-P23 Keywords : public pensions * PAYG * unskilled migration Subject RIV: AH - Economics Impact factor: 1.109, year: 2014

  9. The migration challenge for PAYG.

    Czech Academy of Sciences Publication Activity Database

    Aslanyan, Gurgen

    2014-01-01

    Ro?. 27, ?. 4 (2014), s. 1023-1038. ISSN 0933-1433 Institutional support: RVO:67985998 Keywords : public pensions * PAYG * unskilled migration Subject RIV: AH - Economics Impact factor: 1.109, year: 2014

  10. MRI of neuronal migration disorders

    International Nuclear Information System (INIS)

    Twenty-one MRI examinations of the brain were performed in 19 children with neuronal migration disorders. Multiplanar oriented spin-echo sequences were on a scanner with 1.5 T. In 8 children we performed an additional turbo-inversion recovery (TIR) sequence. Results of sonography or CT from five children were compared with MRI scans. Using the actual nomenclature, we found the following migration disorders: Lissencephaly (n=6), cobblestone lissencephaly with Walker-Warbung syndrome (WWS) (n=2), polymicrogyria and schizencephaly (n=2), focal heterotopia (n=5), diffuse heterotopie (n=2) and hemimegalencephaly (n=2). MRI was superior to CT and sonography in all children. Except for the two boys with WWS, the TIR sequence was the best to demonstrate the changes in migration disorder because of the high contrast between gray and white matter. We demonstrate the characteristic features of the different migration disorders and compare them with the existing literature. (orig.)

  11. The effect of hydrocarbons on the microstructural evolution in rock salt: a case study on hydrocarbon bearing Ara salt from the South Oman Salt Basin

    Science.gov (United States)

    Schmatz, Joyce; Urai, Janos L.; Wübbeler, Franziska M. M.; Sadler, Marc

    2014-05-01

    It has been shown that dilatant deformation promotes the incorporation of hydrocarbons into typically low permeable rock salt (Schoenherr et al., 2007). However, there is not much knowledge on subsequent mechanisms related to recrystallization processes, which cause morphological and chemical changes of the carbonic inclusions. This work aims to contribute to an increased understanding of fluid inclusion dynamics related to grain boundary migration recrystallization and hence to facilitate the interpretation of complex microstructures in recrystallized, multiphase salt rocks. In this case study we investigate hydrocarbon-impregnated salt from the Cambrian Ara Group in the South Oman Salt Basin. The samples were cored from cm-m thick anhydrite-salt sequences overlying hydrocarbon bearing carbonate stringers in 3300 m depth. The anhydrite layers consist mainly of fine-grained anhydrite, which contains calcite, dolomite, and olivine inclusions. Solid bitumen and lighter hydrocarbon phases are observed in between the anhydrite grains and along cracks. Anhydrite layers host salt veins, which contain fragments of anhydrite. These fragments do not differ in composition or structure from the host material and the related vein microstructures indicate crack-seal mechanisms. Halite in the salt layers is almost entirely recrystallized with solid inclusions consisting of anhydrite, calcite, dolomite and olivine with hydrocarbon-coatings present inside grains and along grain boundaries. Solid inclusions cause pinning indicated by a decreased recrystallized grain size and by the presence of grains with preserved substructures representing earlier deformation phases. We observe two types of carbonic inclusions: I) solid bitumen coatings along grain boundaries and microcracks, interpreted to be incorporated into the salt in an overpressure state that allowed dilatancy of the salt, and II) less degraded, liquid hydrocarbons along grain boundaries in the vicinity of the anhydrite, interpreted to be incorporated into the salt in a subsequent deformation phase. Type II inclusions usually form arrays of isolated inclusions (liquid hydrocarbons, vapor, and aqueous phases in minor proportions) along grain boundaries of the recrystallized grains, presumably formed in a surface-energy controlled shrinking process from thin fluid films. Here, the contact with mobile grain boundaries promoted necking down and decomposition of multiphase inclusions. We present a model, which describes the dynamic behavior of liquid hydrocarbons in mobile grain boundaries after their enclosure into the salt layers. The model is based on numerous microanalytical methods, such as optical microscopy, fluorescence microscopy, cryo-SEM, and EDX. Schoenherr, J., et al. (2007), Limits to the sealing capacity of rock salt: A case study of the infra-Cambrian Ara Salt from the South Oman salt basin, AAPG Bulletin, 91(11), 1541-1557

  12. Palaearctic-African Bird Migration

    DEFF Research Database (Denmark)

    Iwajomo, Soladoye Babatola

    2013-01-01

    Bird migration has attracted a lot of interests over past centuries and the methods used for studying this phenomenon has greatly improved in terms of availability, dimension, scale and precision. In spite of the advancements, relatively more is known about the spring migration of trans-Saharan migrants than autumn migration. Information about the behavior and interactions of migrants during the nonbreeding season in sub-Saharan Africa is also scarce for many species. Furthermore, very little is known about intra-African migration. This thesis summarizes my research on the autumn migration of birds from Europe to Africa and opens up the possibility of studying intra-African migration. I have used long-term, standardized autumn ringing data from southeast Sweden to investigate patterns in biometrics, phenology and population trends as inferred from annual trapping totals. In addition, I investigated the relationship between the timing of autumn migration and climatic variations at local and spatial scale. The first three papers focused on speciesspecific analysis. In them I described the age-specific patterns in biometrics, phenology and migration strategies as well as trends in the population of the species. The papers show that adult and juvenile birds can use different migration strategies depending on time of season and prevailing conditions. Also, the fuel loads of some individuals were theoretically sufficient for a direct flight to important goal area, but whether they do so is still unknown. The fourth paper and one manuscript investigate the behavior of garden warblers Sylvia borin, during the non-breeding season in Nigeria. The first paper shows that the species also utilizes habitats south of the savannah region, presumably on its way to the final goal area. Individuals also molt their flight feathers at this location and intraspecific interactions are non-aggressive. The second manuscript investigates whether variations in the timing of migration of wader species at a stopover site in southeast Sweden is influence by local or regional climatic variables. The manuscript reveals that both factors may be important and that species breeding close to Ottenby and those breeding in the arctic may be affected by either of the two variables. In addition, breeding success is probably an important factor influencing timing of migration. The third manuscript compares the breeding possibilities between two related cuckoo species using home range estimates derived from satellite telemetry data. The influence host species availability, foraging habitats are discussed.

  13. Decontamination of hydrocarbon contaminated soil

    International Nuclear Information System (INIS)

    This patent describes the method of treating hydrocarbon contaminated soil. It comprises forming the soil into a flowing particulate stream, forming an aqueous liquid mixture of water and treating substance that reacts with hydrocarbon to form CO2 and water, dispersing the liquid mixture into the particulate soil stream to wet the particulate, allowing the substance to react with the wetted soil particulate to thereby form CO2 and water, thereby the resultant soil is beneficially treated, the stream being freely projected to dwell at a level and then fall, and the dispersing includes spraying the liquid mixture into the projected stream at the dwell, the substance consisting of natural bacteria, and at a concentration level in the mixture of between 100 to 3,000 PPM of bacteria to water, the soil forming step including impacting the soil to reduce it to particles less than about 1 inches in cross dimension, and including forming the wetting particulate into a first layer on a surface to allow the substance to react

  14. Unsaturated medium hydrocarbons pollution evaluation

    International Nuclear Information System (INIS)

    When the so called porous unsaturated medium, that's the vertical subsoil section between both the ground and water-table level, is interested by a hydrocarbons spill, the problem to evaluate the pollution becomes difficult: considering, essentially, the natural coexistence in it of two fluids, air and water, and the interactions between them. This paper reports that the problems tend to increase when a third fluid, the pollutant, immiscible with water, is introduced into the medium: a three-phases flow, which presents several analogies with the flow conditions present in an oil-reservoir, will be established. In such a situation, it would be very useful to handle the matter by the commonly used parameters in the oil reservoirs studies such as: residual saturation, relative permeability, phases mobility, to derive a first semiquantitative estimation of the pollution. The subsoil pollution form hydrocarbons agents is one of the worldwide more diffused causes of contamination: such events are generally referable to two main effects: accidental (oil pipeline breakdowns, e.g.), and continuous (underground tanks breaks, industrial plants leakages, e.g.)

  15. Hydrocarbon production with nuclear explosives

    International Nuclear Information System (INIS)

    The tremendous energy of nuclear explosives and the small dimensions of the explosive package make an ideal combination for drill-hole explosive emplacement in deep, thick hydrocarbon deposits. Potential applications exist in fracturing low permeability natural-gas and petroleum formations for stimulating production, fracturing oil shale to permit in situ retorting, and creating storage chimneys for natural gas, liquefied petroleum gas, petroleum, petroleum products, helium, and other fluids. Calculations show, for example, that less than 100 shots per year would be needed to stabilize the natural gas reserves to production ratio. Under the Government-industry Plowshare program, two experiments, Projects Gasbuggy and Rulison, were conducted to stimulate natural gas production from low-permeability formations. Incomplete information indicates that both were technically successful. Potential problems associated with the use of nuclear explosives for underground engineering applications are radioactive contamination, maximum yield limitations, high costs of detonating contained nuclear explosives, and adverse public opinion. Results at Project Gasbuggy and other considerations indicated that the problem of radioactive contamination was about as predicted and not an insurmountable one. Also, it was demonstrated that shots at adequate depths could be detonated without appreciable damage to existing surface and subsurface buildings, natural features, and equipment. However, costs must be reduced and the public must be better informed before these techniques can be widely used in field operations. On the basis of present knowledge, the potential of nuclear-explosive stimulation of hydrocarbon production appears good. Additional field experiments will be required to adequately explore that potential. (author)

  16. Migration from and to Sudan

    OpenAIRE

    MOHAMED-ALI, Amna Omer

    2011-01-01

    In this paper, a survey of the demographic aspects of migration from and to Sudan is presented. One of the main limitations in approaching migration from and to Sudan is the poor data coverage, quality and accuracy of official statistics. Emigration seems to be increasing. As to immigration patterns, Sudan has historically hosted a large number of refugees from neighboring countries and Sudan is also an important origin country for asylum seekers and refugees. The characteristics of Sudanese ...

  17. Does Higher Education Enhance Migration?

    OpenAIRE

    Haapanen, Mika; Böckerman, Petri

    2013-01-01

    This paper examines the causal impact of education on within-country migration. A major higher education reform took place in Finland in the 1990s. It gradually transformed former vocational colleges into polytechnics and expanded higher education to all regions. The reform created exogenous variation in the regional supply of higher education. Using the reform as an instrument, our estimation results show that polytechnic graduates have a 7.5 (13.7) percentage points higher migration probabi...

  18. Migration of radionuclides in soil

    International Nuclear Information System (INIS)

    Due to the growing amounts of low-level radioactive waste being produced from the nuclear industry and research establishments, there is considerable interest in the study of migration of radionuclides from the shallow-land burial sites. A brief description is presented about some aspect of effectiveness of soil in retarding the migration of radionuclides with special emphasis given to those environmentally critical fission and activation products, elements. (author)

  19. Migration and deforestation in Indonesia

    OpenAIRE

    Darmawan, Rivayani; Klasen, Stephan; Nuryantono, Nunung

    2015-01-01

    Indonesia now has the highest deforestation rate in the world, with an average increase of about 47,600 ha per year. As a result, the nation is one of the largest emitters of greenhouse gases in the world and putting its rich biodiversity at risk. Although the literature discussing the political economy of Indonesia commercial's logging is growing, only a small amount focuses on the relationship between migration and deforestation. Migration may contribute to the forest cover change, as migra...

  20. Diffusion induced grain boundary migration

    International Nuclear Information System (INIS)

    While grain boundaries and interphase boundaries provide high diffusivity paths in solids, little bulk composition change can occur at temperatures where lattice diffusion is frozen out unless the boundaries migrate. That the diffusion itself can induce boundary migration has been suspected for some time. This study reviews evidence that the effect is indeed common, and this conclusion is reinforced by additional observations on three systems

  1. European Integration and Labour Migration

    Directory of Open Access Journals (Sweden)

    Julda Kielyte

    2010-11-01

    Full Text Available The present paper studies how European integration might affect the migration of workers in the enlarged EU. Unlike the reduced-form migration models, we base our empirical analysis on the theory of economic geography à la Krugman (1991, which provides an alternative modelling of migration pull and push factors. Parameters of the theoretical model are estimated econometrically using historical migration data. Our empirical findings suggest that European integration would trigger selective migration between the countries in the enlarged EU. In the Baltics, Lithuania would gain about 7.25% of the total work force. In the Visegrád Four, the share of the mobile labour force would increase the most in Hungary, 8.35%, compared to the pre-integration state. Our predictions for the East-West migration are moderate and lower than those of reduced-form models: between 5.44% (from the Baltics and 3.61% (from the Visegrád Four would emigrate to the EU North. Because migrants not only follow market potential, but also shape the region’s market potential, the long-run agglomeration forces are sufficiently weak to make a swift emergence of a core-periphery pattern in the enlarged EU very unlikely.

  2. The dynamics of mass migration.

    Science.gov (United States)

    Massey, D S; Zenteno, R M

    1999-04-27

    We specify a set of equations defining a dynamic model of international migration and estimate its parameters by using data specially collected in Mexico. We then used it to project the a hypothetical Mexican community population forward in time. Beginning with a stable population of 10,000 people, we project ahead 50 years under three different assumptions: no international migration; constant probabilities of in- and out-migration, and dynamic schedules of out- and in-migration that change as migratory experience accumulates. This exercise represents an attempt to model the self-feeding character of international migration noted by prior observers and theorists. Our model quantifies the mechanisms of cumulative causation predicted by social capital theory and illustrates the shortcomings of standard projection methodologies. The failure to model dynamically changing migration schedules yields a 5% overstatement of the projected size of the Mexican population after 50 years, an 11% understatement of the total number of U.S. migrants, a 15% understatement of the prevalence of U.S. migratory experience in the Mexican population, and an 85% understatement of the size of the Mexican population living in the United States. PMID:10220465

  3. Investigation on nuclide migration behaviors

    International Nuclear Information System (INIS)

    In this study, we investigated the properties of geochemical reactions and sorption of high-level radionuclides and highly-mobile radionuclides in deep geological disposal environments. We also analyzed the dissolution properties of pyro wastes and constructed databases for the geochemical reactions and sorption for the safety assessment of HLW disposal. Technologies for measuring diffusion depths of radionuclides through fracture surfaces and rock matrix were developed in KURT conditions and their diffusion properties were analyzed and evaluated. The combined reactions of radionuclide/mineral/microbe in deep disposal environments were investigated and the effects of microbe on the radionuclide migration and disposal system behaviors were evaluated. In-situ solute migration system and on-line monitoring system were installed in KURT and the migration and retardation behaviors of various solutes and their interaction with fracture-filling materials were investigated. Basic properties of KURT groundwater colloids were analyzed using various methods. In addition, in-situ colloid migration experiments through a rock fracture were carried out and the developed migration model was verified. We have participated in Colloid Formation and Migration (CFM) international joint project in GTS and obtained reliability for our research results by comparing research results each other

  4. Palaearctic-African Bird Migration

    DEFF Research Database (Denmark)

    Iwajomo, Soladoye Babatola

    Bird migration has attracted a lot of interests over past centuries and the methods used for studying this phenomenon has greatly improved in terms of availability, dimension, scale and precision. In spite of the advancements, relatively more is known about the spring migration of trans-Saharan m......Bird migration has attracted a lot of interests over past centuries and the methods used for studying this phenomenon has greatly improved in terms of availability, dimension, scale and precision. In spite of the advancements, relatively more is known about the spring migration of trans...... birds from Europe to Africa and opens up the possibility of studying intra-African migration. I have used long-term, standardized autumn ringing data from southeast Sweden to investigate patterns in biometrics, phenology and population trends as inferred from annual trapping totals. In addition, I...... population of the species. The papers show that adult and juvenile birds can use different migration strategies depending on time of season and prevailing conditions. Also, the fuel loads of some individuals were theoretically sufficient for a direct flight to important goal area, but whether they do so is...

  5. Migration and Security of States

    Directory of Open Access Journals (Sweden)

    Cristian Jura

    2012-05-01

    Full Text Available The main topic of this article is represented by an attempt to encounter an answer to the questionwhether there is any connection between migration/minorities and security and how do they mutuallyinfluence. Pursuant to the analyses performed during the last years, we may definitely state that there is abiunivoque connection between migration/minorities and security. The migration/minorities may influencesecurity positively or negatively. Both states are influenced, the state they are leaving, and the state where theyare to settle. I have chosen to select in parallel two concepts: migration and minorities. The scientific groundthat determined me to decide to use such an approach is that migrants, sooner or later, turn into groups thatshare the same values, the same culture, the same traditions, the same language etc. Therefore, the migrantsturn into a minority living on the territory of the state where they have migrated. Practically, migration may bedefined by the movement of an important number of individuals, but, as these groups of individuals settle,they turn into minorities.

  6. Anomalous dynamics of cell migration.

    Science.gov (United States)

    Dieterich, Peter; Klages, Rainer; Preuss, Roland; Schwab, Albrecht

    2008-01-15

    Cell movement--for example, during embryogenesis or tumor metastasis--is a complex dynamical process resulting from an intricate interplay of multiple components of the cellular migration machinery. At first sight, the paths of migrating cells resemble those of thermally driven Brownian particles. However, cell migration is an active biological process putting a characterization in terms of normal Brownian motion into question. By analyzing the trajectories of wild-type and mutated epithelial (transformed Madin-Darby canine kidney) cells, we show experimentally that anomalous dynamics characterizes cell migration. A superdiffusive increase of the mean squared displacement, non-Gaussian spatial probability distributions, and power-law decays of the velocity autocorrelations is the basis for this interpretation. Almost all results can be explained with a fractional Klein-Kramers equation allowing the quantitative classification of cell migration by a few parameters. Thereby, it discloses the influence and relative importance of individual components of the cellular migration apparatus to the behavior of the cell as a whole. PMID:18182493

  7. 40 CFR 52.1877 - Control strategy: Photochemical oxidants (hydrocarbons).

    Science.gov (United States)

    2010-07-01

    ... oxidants (hydrocarbons). 52.1877 Section 52.1877 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY....1877 Control strategy: Photochemical oxidants (hydrocarbons). (a) The requirements of Subpart G of this... national standard for photochemical oxidants (hydrocarbons) in the Metropolitan Cincinnati...

  8. 21 CFR 573.740 - Odorless light petroleum hydrocarbons.

    Science.gov (United States)

    2010-04-01

    ... 2010-04-01 false Odorless light petroleum hydrocarbons. 573.740 Section 573...Additive Listing § 573.740 Odorless light petroleum hydrocarbons. Odorless light petroleum hydrocarbons complying with §...

  9. 21 CFR 178.3650 - Odorless light petroleum hydrocarbons.

    Science.gov (United States)

    2010-04-01

    ...2010-04-01 2009-04-01 true Odorless light petroleum hydrocarbons. 178.3650 Section 178...Production Aids § 178.3650 Odorless light petroleum hydrocarbons. Odorless light petroleum hydrocarbons may be safely used, as...

  10. Secondary Surveillance Radar Antenna

    OpenAIRE

    Schejbal, Vladimír; Bezoušek, Pavel; Pidanič, Jan; Chyba, Milan

    2013-01-01

    This paper deals with a secondary surveillance radar (SSR) array antenna, which is intended for a system combining the secondary surveillance radar antenna and the primary surveillance radar antenna. It describes the patch array elements and the synthesis for the secondary surveillance radar array, considering both elevation and azimuth patterns for sum, difference, and sidelobe-suppression beams, and suspended stripline couplers. The utilization of multilayer techniques allows the connection...

  11. The enrichment secondary market

    International Nuclear Information System (INIS)

    This paper will addresses two topics: the background to the present status of the enrichment secondary market and the future outlook of the secondary market in enrichment services, and the viability of the nuclear fuel brokerage industry. These two topics are inevitably connected, as most secondary market activity, not only in enrichment but also in natural uranium, has traditionally been conducted with the participation of brokers. Therefore, the author interrelates these topics

  12. Secondary Controlled Swing Drive

    OpenAIRE

    Pettersson, Karl

    2008-01-01

    The purpose of the thesis has been to design and simulate different concepts of a secondary controlled swing drive for a wheel excavator. Secondary control is a known technology in the field of hydraulics that offers precise positioning as well as the possibility of energy recuperation. Secondary control is today used in certain industrial applications and is rather unemployed in mobile machinery. An excavator moves high loads in cyclic motions which are ideal conditions for energy recuperati...

  13. Musei del migration heritage

    Directory of Open Access Journals (Sweden)

    Patrizia Dragoni

    2015-01-01

    Full Text Available A partire dalla seconda metà degli scorsi anni ’60, al radicale mutamento del contesto sociale, politico ed economico si è accompagnata una profonda innovazione anche culturale. La nozione antropologica di cultura contrapposta alla visione idealistica, l’inedito e forte interesse per la cultura materiale, l’enunciazione del concetto di bene culturale da parte della Commissione Franceschini, la fortuna della Public History portano ad un rivolgimento degli statuti disciplinari delle scienze storiche, che iniziano ad occuparsi di storia sociale, privilegiando le fonti informative spontanee e dando corso ad esperienze di storia orale. A tutto ciò si accompagna una notevole trasformazione delle tematiche e della funzione sociale dei musei. Questo lavoro riferisce, relativamente a questo più generale contesto, della formazione e della diffusione in ambito internazionale e italiano dei musei dedicati alla storia dell’emigrazione, dà conto delle loro possibili prospettive di utilità sociale in ordine alla integrazione degli attuali immigrati in Italia e illustra a titolo di esempio il museo recentemente allestito a Recanati.Since the second half of the 1960s of the 20th century, a profound cultural innovation was accompanied to the radical change in the social, political and economic climate. The anthropological notion of culture as opposed to idealistic vision, the unusual and strong interest in material culture, the enunciation of the concept of cultural property by the Franceschini Commission, the luck of the Public History bring a change of the disciplinary statutes of historical sciences, which begin to attend to social history, focusing on the spontaneous sources of information and initiating experiences of oral history. To all this a remarkable transformation of the themes and of the social function of museums is added. This paper illustrates, in relation to this more general context, the foundation and the dissemination of museums dedicated to the history of migration in Italy and in the world, enunciates their possible social utility for the integration of present migrants in Italy and illustrates, by way of example, the museum recently opened in Recanati.

  14. An Easy Synthesis of Two Cage Hydrocarbons.

    Science.gov (United States)

    Dong, Dao Cong

    1982-01-01

    Describes a simple, three-step synthesis of two cage molecules, birdcage hydrocarbon (VIII) and its homologue, the homobirdcage hydrocarbon IX. Indicates that all products are easily purified and formed in high yields in this activity suitable for advanced undergraduate laboratory courses. (Author/JN)

  15. Polyaromatic hydrocarbons pollution assessment of Slovenian sea:

    OpenAIRE

    BAJT Oliver

    2007-01-01

    The paper assesses pollution of the Slovenian sea in terms of polyaromatic hydrocarbons content in sediment samples and mussels. For this purpose, fluorescence spectroscopy was appliedf as a screening method.Elevated convcentrations of polyaromatic hydrocarbons were obtained in municipal harbours of the three Slovenian coastal cities...

  16. Polyaromatic hydrocarbons pollution assessment of Slovenian sea

    OpenAIRE

    BAJT Oliver

    2015-01-01

    The paper assesses pollution of the Slovenian sea in terms of polyaromatic hydrocarbons content in sediment samples and mussels. For this purpose, fluorescence spectroscopy was appliedf as a screening method.Elevated convcentrations of polyaromatic hydrocarbons were obtained in municipal harbours of the three Slovenian coastal cities...

  17. Total Petroleum Hydrocarbons (TPH): ToxFAQs

    Science.gov (United States)

    ... chemicals, but they are all made mainly from hydrogen and carbon, called hydrocarbons. Scientists divide TPH into ... total petroleum hydrocarbons (TPH)? There is no medical test that shows if ... by its smell on the breath or clothing. Benzene can be measured in exhaled ...

  18. Distribution of hydrocarbons in fractured clay soils

    International Nuclear Information System (INIS)

    Surface or near surface spills of hydrocarbons such as gasoline and diesel often occur into clay soils which are fractured and unsaturated.. The distribution and extent of contamination must be determined prior to the development of remediation methods. The movement of the free phase hydrocarbon occurs primarily by infiltration into the fractures and the initial distribution of hydrocarbon in the soil is controlled by fracture geometry. Over time; however, significant changes in the distribution of the hydrocarbon occur. The dominant mechanism for long-term re-distribution of hydrocarbons is through diffusion and adsorption of the aqueous phase hydrocarbon into the matrix between the fractures. The implication of this change in hydrocarbon distribution is that different remediation schemes must be adopted at various times after the initial spill occurred. Double reservoir diffusion testing was undertaken for samples of re-compacted clay in order to define the coefficient of molecular diffusion and adsorption which control the rate at which the re-distribution of benzene would take place. Specific experimental and analytical protocols were developed for the testing of volatile organic chemicals. Estimates were made of the rate of re-distribution of hydrocarbon between the free-phase in the fracture and the aqueous phase in the matrix for a given fracture geometry. These estimates are compared to qualitative estimates of the rate of re-distribution as observed in typical site investigations

  19. Contribution to radiolysis study of liquid hydrocarbons

    International Nuclear Information System (INIS)

    This work deals with radiolysis of liquid hydrocarbons. First, the radiochemical yields of various products are correlated with the theoretical bond energies, for some hydrocarbons. Several values of scavenging parameter ?sub(S) are calculated and the methods for these determinations are criticized. In the last part, we present a new method for the calculation of electron scavenging rate constants

  20. Polynuclear aromatic hydrocarbons for fullerene synthesis in flames

    Science.gov (United States)

    Alford, J. Michael; Diener, Michael D.

    2006-12-19

    This invention provides improved methods for combustion synthesis of carbon nanomaterials, including fullerenes, employing multiple-ring aromatic hydrocarbon fuels selected for high carbon conversion to extractable fullerenes. The multiple-ring aromatic hydrocarbon fuels include those that contain polynuclear aromatic hydrocarbons. More specifically, multiple-ring aromatic hydrocarbon fuels contain a substantial amount of indene, methylnapthalenes or mixtures thereof. Coal tar and petroleum distillate fractions provide low cost hydrocarbon fuels containing polynuclear aromatic hydrocarbons, including without limitation, indene, methylnapthalenes or mixtures thereof.

  1. Mechanistic studies on the OH-initiated atmospheric oxidation of selected aromatic hydrocarbons

    OpenAIRE

    Nehr, Sascha

    2012-01-01

    Benzene, toluene, the xylenes, and the trimethylbenzenes are among the most abundant aromatic trace constituents of the atmosphere mainly originating from anthropogenic sources. The OH-initiated atmospheric photo-oxidation of aromatic hydrocarbons is the predominant removal process resulting in the formation of O3 and secondary organic aerosol. Therefore, aromatics are important trace constituents regarding air pollution in urban environments. Our understanding of aromatic photo-oxidation pro...

  2. Chamber studies of SOA formation from aromatic hydrocarbons: observation of limited glyoxal uptake

    OpenAIRE

    S. Nakao; Liu, Y. (Yahui); Tang, P; C.-L. Chen; Zhang, J; D. R. Cocker III

    2012-01-01

    This study evaluates the significance of glyoxal acting as an intermediate species leading to secondary organic aerosol (SOA) formation from aromatic hydrocarbon photooxidation under humid conditions. Rapid SOA formation from glyoxal uptake onto aqueous (NH4)2SO4 seed particles is observed in agreement with previous studies; however, glyoxal did not partition significantly to SOA (with or without aqueous seed) during aromati...

  3. Near-surface hydrocarbon anomalies in shelf sediments off Spitsbergen: Evidences for past seepages

    Science.gov (United States)

    Knies, Jochen; Damm, Ellen; Gutt, Julian; Mann, Ute; Pinturier, Laurence

    2004-06-01

    As global warming occurs, the dissociation of bound methane on Arctic shelves due to ocean current temperature changes may become a major contributor to the global methane budget, and thus contribute to strong positive climate feedback mechanisms. However, little is known about the magnitude and fate of methane emissions from shallow submarine sediments to the atmosphere in the peculiar area. In this paper, we present one of the first direct evidences for seepage on the northwestern Barents Sea shelf. By studying the molecular and isotopic signatures of low-molecular-weight hydrocarbons in seawater, near-surface sediment pore space and the sediment matrix at 26 locations, we provide a detailed view on the partitioning of gaseous hydrocarbons in the sediment-water interface off Spitsbergen. In the free gas phase, low concentration of methane (˜28 ng/g wet Sediment) paired with constantly high isotopic values (˜-65‰) is consistent with high impact of methane oxidation on the isotopic composition. In contrast, high concentrations of adsorbed CH4 (up to 5292 ng/g wet signatures of adsorbed CH4 (-38--60‰; ˜100-˜5300 ng/g wet <63 ?m) and C2H6 (-20--36‰; ˜30-˜1700 ng/g wet <63 ?m) indicate an integrated, but strongly varying signal of historic thermally derived hydrocarbon plumes plus in situ adsorbed gas of biological origin. This suggests a minimal exchange and unlike histories of free and adsorbed gas. The majority of gaseous hydrocarbons in the adsorbed pool may be the result of past seepages. Past upward flow of thermogenic gas and impregnation with mature hydrocarbons was particularly strong along tectonic lineaments. Active petroleum source rocks along the continental margin and migration of gaseous hydrocarbons at re-activated fault systems might explain the anomalies along these conduits.

  4. Private sector perspectives on hydrocarbon contamination

    International Nuclear Information System (INIS)

    In order to effectively resolve a problem, one should attempt to gain a comprehensive understanding of all facets of the problem. With regard to hydrocarbon contamination, it is essential for regulators, consultants, attorneys, bankers, business owners, and others involved with this issue to develop a comprehensive understanding of the major perspectives associated with hydrocarbon contamination in order to address and effectively resolve the specific hydrocarbon contamination issues these groups are, or will be, facing. The purpose of this paper is to identify the hydrocarbon contamination issues from private and public sector perspectives. In doing so, the author hopes to present another important perspective that will provide those involved with hydrocarbon contamination a more complete picture of the scope of the problem

  5. Mechanisms and modelling of gas migration from deep radioactive waste repositories

    International Nuclear Information System (INIS)

    This report discusses the mechanisms by which gas is able to migrate through the far-field. The mechanisms available are diffusion or advection of gas dissolved in groundwater or free gas phase flow as either bubbles or a continuous stream of gas. Modelling approaches adopted to assess the migration are (a) simple use of Darcy's law with an effective permeability to gas, (b) the development of a model based on the representation of the far-field rock as a bundle of capillaries with a suitable distribution of radii, and (c) the use of a numerical model of two-phase flow in porous media. Finally, surveys have been carried out of published work on gas escape from underground storage caverns and of literature relating to gas movement from underground hydrocarbon accumulations to determine whether these may be potential sources of data or understanding of underground gas migration relevant to that from deep waste repositories. (author)

  6. Rural-Urban Migration in Colombia.

    Science.gov (United States)

    Schultz, T. Paul

    The rural-urban migration pattern in Colombia during the last 25 years has resulted in a population increase in urban areas from 30 to 52 percent of the total population. This study explores the causes of internal migration. Migration rates are estimated for various groups in the population to clarify who migrates and to where. A model of…

  7. Distance and Intrastate College Student Migration

    Science.gov (United States)

    Alm, James; Winters, John V.

    2009-01-01

    Most studies of student migration focus on "interstate" migration of college students, largely because the aggregate data typically used are limited in geographic specificity to states. However, interstate migration is only a small part of the total student migration. Public institutions generally get most of their students from within their…

  8. Decomposition of hydrocarbon pollutants in air by gliding arc discharge

    International Nuclear Information System (INIS)

    The object of this investigation was the removal of hydrocarbons from simulators of exhaust gases (hydrocarbons + air) by a gliding arc. The presented results show that almost complete (?90%) removal of hydrocarbons was obtained. The hydrocarbons were converted to carbon oxides and H2O. The hydrocarbons conversion rate increased with increasing residence time, temperature and pressure of the operating gas, and initial concentration of hydrocarbons. The presented method can be useful for the removal of hydrocarbons from exhaust gases when the concentration of the hydrocarbons is below its lower flammable limit. (author)

  9. Simulation of the migration of mineral oil from recycled paperboard into dry foods by Tenax®?

    Science.gov (United States)

    Zurfluh, Michael; Biedermann, Maurus; Grob, Koni

    2013-01-01

    Conventional migration testing for long-term storage at ambient temperature with Tenax® was applied to a recycled paperboard as well as to the same paperboard with a polyethylene or polypropylene film in between. Test conditions were from the European Union plastic Regulation 10/2011, that is, 10 days at 60°C, but previous standard conditions of 10 days at 40°C were also applied. The results were compared with the migration into real packs made of the same packaging material containing six test foods and stored over 9 months. For the direct contact, simulation at 60°C overestimated the maximum migration of the saturated hydrocarbons in the real packs by 73%. Simulation reflected hardly any effect by the plastic films and resulted in an overestimation of the maximum migration into the real packs by a factor of 5.1 and 27 for the polyethylene and the polypropylene film, respectively. Analogous simulation was performed with polenta (corn semolina) instead of Tenax®. Three main causes for this deviation were identified: (i) at 60°C, migration reached beyond n-C??, whereas it ends at about n-C?? in reality. (ii) Tenax® is a far stronger adsorbent than foods, resulting in almost complete extraction. (iii) The significant barrier effect of polypropylene films at ambient temperature is lost at increased temperature. The suitability of such simulation for the prediction of long-term migration is questioned. PMID:23710606

  10. Gender, migration, and career trajectories in Malaysia.

    Science.gov (United States)

    Chattopadhyay, A

    1998-08-01

    With data from the Malaysian Family Life Survey, I use a continuous-state hazards model to study the impact of migration on the dynamics of individuals' careers. I distinguish between the effects of family migration and solo migration by gender. The results show that migration alters the career trajectory primarily by accelerating the process of occupational mobility rather than by increasing the level of occupational attainment. Further, the effect of migration on careers varies by type of migration, especially for women. Male-female differences in the outcome of family migration, however, are visible only in transitions into and out of employment. PMID:9749325

  11. Wakes in large hydrocarbon molecules

    International Nuclear Information System (INIS)

    Electron capture-and-loss-to-the-continuum processes (ECC and ELC, respectively) for a fast projectile traversing atomic, molecular or solid targets produces a forward directed beam of electrons roughly velocity matched with projectile, i.e. v/sub e/ ? v/sub p/. These continuum electrons, detected at -- O/sup o/, form a cusp. Cups shapes for atomic gas and solid targets differ in their skewness and widths. There is also a difference in skewness, width and cross sections between ELC and ECC cusps for atomic (and molecular) gas targets. These cusp shape differences are a clue to the physical origin of the continuum electrons. In an attempt to understand the difference in cusp shapes between atomic and solid targets, the authors have bridged the gap by systematically varying target size, using hydrocarbon (C/sub m/H/sub n/) molecular gas targets ranging from m = 1 to m = 7. 11 references, 5 figures, 1 table

  12. Preparation of aromatic hydrocarbon monocrystals

    International Nuclear Information System (INIS)

    This report explains the technique developed and used for the production of organic monocrystals, necessary for the detection of ? radiation. The Bridgman process has been used. A glass bulb containing the substance to be crystallized passes through a vertical thermo-regulated furnace maintained slightly above the fusion point of the substance. The bottom of the bulb has a conical section which ends with a thin capillary in order to obtain a single crystal nucleus. This method has been implemented to several hydrocarbons (naphthalene, anthracene, stilbene, tolan, tetraphenylethylene, tetra-phenyl-butadiene). The report describes successively: the furnaces, the process used for the filling of the bulbs, the degassing of the products, and for each compound, the details of the preparation and purification and the size of the obtained crystals. (J.S.)

  13. Fate of hydrocarbons in solids

    International Nuclear Information System (INIS)

    This paper describes concepts, uses, and limitations of state-of-the-art mathematical environment pollutant fate modeling for use in hydrocarbon fate studies and analyses of environmental quality. Terrestrial chemicals fate modeling has traditionally been performed for three distinct sub-compartments: the land surface (of watershed); the unsaturated soil (or soil) zone; and the saturated (or groundwater) zone of the region. An evaluation of the fate of inorganic compounds in soil and groundwater requires a detailed consideration of the physical, chemical, and biological processes and reactions involved, such as complexation, absorption, precipitation, oxidation-reduction, chemical speciation, and biological reactions to determine the free metal concentration in soil solutions. These processes can affect such characteristics as species solubility, availability for biological uptake, physical transport, and corrosion potential

  14. Polycyclic aromatic hydrocarbons with SPICA

    CERN Document Server

    Berne, O; Mulas, G; Tielens, A G G M; Goicoechea, J R

    2009-01-01

    Thanks to high sensitivity and angular resolution and broad spectral coverage, SPICA will offer a unique opportunity to better characterize the nature of polycyclic aromatic hydrocarbons (PAHs) and very small grains (VSGs), to better use them as probes of astrophysical environments. The angular resolution will enable to probe the chemical frontiers in the evolution process from VSGs to neutral PAHs, to ionized PAHs and to "Grand-PAHs" in photodissotiation regions and HII regions, as a function of G$_0$/n (UV radiation field / density). High sensitivity will favor the detection of the far-IR skeletal emission bands of PAHs, which provide specific fingerprints and could lead to the identification of individual PAHs. This overall characterization will allow to use PAH and VSG populations as tracers of physical conditions in spatially resolved protoplanetary disks and nearby galaxies (using mid-IR instruments), and in high redshift galaxies (using the far-IR instrument), thanks to the broad spectral coverage SPIC...

  15. Volatile hydrocarbons in pharmaceutical solutions

    Energy Technology Data Exchange (ETDEWEB)

    Kroneld, R. (Department of Medicine, University of Turku (Finland))

    1991-07-01

    Volatile pollutants such as hydrocarbons have, during many years, been analysed in small concentrations in air, water, food, pharmaceutical solutions, and human blood and tissues. It has also been shown that such substances have unexpected consequences for cell cultures and scientific experiments. These substances also accumulate in patients receiving haemodialysis and these patients are exposed to quite high concentrations. The knowledge of the toxicity of such compounds has led to the development of maximum limit concentrations with the aim to decrease the exposure of humans. This paper discusses the problems of human exposure in general and especially through pharmaceutical solutions, and the possibilities of eliminating such compounds with the aim of decreasing the exposure as a hygienic challenge.

  16. Thermal maturity history and implications for hydrocarbon exploration in the Catatumbo basin, Colombia

    International Nuclear Information System (INIS)

    A thermal model integrated with oil and gas geochemical study has been constructed for the Catatumbo basin, Colombia for provides petroleum system data for hydrocarbon exploration. The calibration of the thermal model with maturity data took into account a changing heat flow scheme which included a thermal increase towards the end of the Jurassic and another one in the early Eocene, associated with rifting events. Locally, active/generating source rocks are within the synclines axes. The hydrocarbon expulsion time for Cretaceous source rocks (Capacho and La Luna formations) started in the upper Paleocene-Eocene, while for the los Cuervos Formation the generation and expulsion started of 1 0 my. The petroleum expelled during the Paleocene-Miocene, were likely accumulated in structures formed since the end of the cretaceous, while the younger structures that resulted from the Andean orogen were charged by remigration from the older structures and additionally with the youngest lately generated hydrocarbons. The accumulations of hydrocarbons are mainly the result of generation and migration locally within the basin. The Catatumbo Basin contains thermogenic wet gases with different degrees of thermal maturity which varies from around 1,0 for 2,5 equivalent Ro. The highest degree of thermal evolution according to maturity indicators and thermal modeling is in the southern area, which is prospective for wet gas. The central and northern area appears more prospective for oil with minor amounts of gas

  17. Secondary hyperkalaemic paralysis

    OpenAIRE

    Evers, S; Engelien, A.; Karsch, V.; HUND, M

    1998-01-01

    Besides the hereditary hyperkalaemic paralysis, a secondary form exists which often mimicks Guillain-Barre syndrome. A 62year old patient is reported on who developed severe hyperkalaemic paralysis on the basis of mild renal failure and additive spironolactone intake. Neurophysiological examinations disclosed normal muscle fibre activity but delayed nerve conduction velocities indicating that the mechanism underlying secondary hyperkalaemic paralysis is different from cha...

  18. Migration and sustainability - compatible or contradictory?

    DEFF Research Database (Denmark)

    Røpke, Inge

    2006-01-01

    When the migration issue is discussed in a sustainability perspective, two questions are vital: 1) What is the relationship between migration and the global population growth? 2) What is the relationship between migration and consumption growth, and how does migration influence the distribution of consumption possibilities both between and within industrialized and developing countries? Based on responses to these questions, it is argued that reasonably managed migration will be compatible with ...

  19. Migration and sustainability - compatible or contradictory?

    DEFF Research Database (Denmark)

    Røpke, Inge

    2006-01-01

    When the migration issue is discussed in a sustainability perspective, two questions are vital: 1) What is the relationship between migration and the global population growth? 2) What is the relationship between migration and consumption growth, and how does migration influence the distribution of...... consumption possibilities both between and within industrialized and developing countries? Based on responses to these questions, it is argued that reasonably managed migration will be compatible with sustainable development....

  20. Secondary fuel delivery system

    Science.gov (United States)

    Parker, David M. (Oviedo, FL); Cai, Weidong (Oviedo, FL); Garan, Daniel W. (Orlando, FL); Harris, Arthur J. (Orlando, FL)

    2010-02-23

    A secondary fuel delivery system for delivering a secondary stream of fuel and/or diluent to a secondary combustion zone located in the transition piece of a combustion engine, downstream of the engine primary combustion region is disclosed. The system includes a manifold formed integral to, and surrounding a portion of, the transition piece, a manifold inlet port, and a collection of injection nozzles. A flowsleeve augments fuel/diluent flow velocity and improves the system cooling effectiveness. Passive cooling elements, including effusion cooling holes located within the transition boundary and thermal-stress-dissipating gaps that resist thermal stress accumulation, provide supplemental heat dissipation in key areas. The system delivers a secondary fuel/diluent mixture to a secondary combustion zone located along the length of the transition piece, while reducing the impact of elevated vibration levels found within the transition piece and avoiding the heat dissipation difficulties often associated with traditional vibration reduction methods.

  1. The financial losses from the migration of nurses from Malawi

    Directory of Open Access Journals (Sweden)

    Muula Adamson S

    2006-11-01

    Full Text Available Abstract Background The migration of health professionals trained in Africa to developed nations has compromised health systems in the African region. The financial losses from the investment in training due to the migration from the developing nations are hardly known. Methods The cost of training a health professional was estimated by including fees for primary, secondary and tertiary education. Accepted derivation of formula as used in economic analysis was used to estimate the lost investment. Results The total cost of training an enrolled nurse-midwife from primary school through nurse-midwifery training in Malawi was estimated as US$ 9,329.53. For a degree nurse-midwife, the total cost was US$ 31,726.26. For each enrolled nurse-midwife that migrates out of Malawi, the country loses between US$ 71,081.76 and US$ 7.5 million at bank interest rates of 7% and 25% per annum for 30 years respectively. For a degree nurse-midwife, the lost investment ranges from US$ 241,508 to US$ 25.6 million at 7% and 25% interest rate per annum for 30 years respectively. Conclusion Developing countries are losing significant amounts of money through lost investment of health care professionals who emigrate. There is need to quantify the amount of remittances that developing nations get in return from those who migrate.

  2. La hydrogeology en la traditional mining of hydrocarbons, mining new

    International Nuclear Information System (INIS)

    Is presented from the point of view of Geosciences, an approach torelations between hydrogeology and mining activities, including those of traditional non - metal deposits of ores and rocks application (underground or open pit), the so-called ''modern mining'' (pickles) and hydrocarbons. Within the traditional mining, hydrogeology participates decisively several aspects, both those related to the feasibility of the projects, water supply for the stage of exploration and exploitation, mineraloductos ácueosand mine operations, such as environmental protection of water resources. In the ''modern mining'' groundwater acquires true character mena when it comes to the use of natural brines, and subject when they are generated by injecting water into an aquifer medium. In the case of hydrocarbons, the spectrum is broader participation at the stage of exploration and exploitation, where the hydrogeology is critical to providing water to camps and processes as well as operations secondary recovery, consumers strongly. From the perspective of environmental protection, are the main protagonists of groundwater the impacts of production, but also the phases are transportation, processing and marketing. They are used in the presentation of case examples of Argentina and Chile, some reflections on the need for an appropriate regulatory framework, especially addressed to Uruguay, and information to protect the population activity production of an unfair detriment, when mining is done responsibly

  3. The Fate of Hydrocarbon Pollution in Kebnekaise, Arctic Sweden

    Science.gov (United States)

    Rosqvist, G. N.; Jarjso, J.; Clason, C.; Jansson, P.; Karlin, T.

    2013-12-01

    A C-130J-30 Super Hercules plane crashed into the west-facing wall of the Kebnekaise mountain (2103 m), Arctic Sweden, on March 15th 2012. When starting from Evenes, Narvik, Norway, the aircraft had 14100 l fuel, 50 l hydraulic oil and 170 l motor oil onboard. Best estimates are that at least 12 000 l of fuel was sprayed over the mountain most of which was buried together with the wreck in a huge snow avalanche that was triggered by the impact in a NW facing cirque on Rabots glacier between ca 1600 and 2000 m. Fuel decontamination was not possible because of the extreme impact site conditions. The Hercules airplane was fueled with JET A-1 which is a hydrocarbon product in the Kerosene/Jet Fuel category consisting of sweetened kerosene and hydrotreated light distillates. The major components of all 'kerosene's' are branched- and straight-chain paraffins and naphthenes (cycloparaffins or cycloalkanes), which normally account for 70% by volume. Aromatic hydrocarbons, such as alkyl benzenes (single ring) and alkylnaphthalenes (double ring) do not exceed 25 % by volume of kerosene. The fuel also contains polycyclic aromatic hydrocarbons (PAH), but in very small volumes compared to the major components. The physical and chemical properties of each component (or block) of the hydrocarbon mixture influence its migration rate and fate. Some components of the fuel will volatilize, some are soluble in water but the vast majority are non-soluble. Although the solubility of these so called Light Nonaqueous Phase Liquids (LNAPL) in water is small they are highly toxic. We need to consider transport of the soluble components of the LNAPL in the melt-water, and transport of the non-soluble components with the melt-water system. Transport and storage can occur through and in snow (or firn), crevasses, and cavities on, in or under the glacier. Storage in, and contamination of, basal sediments, located below the glacier, or pro-glacial sediments, in front of the glacier are also possible. We have traced and determined the chemical evolution of the polluted snow and firn at the source zone during two summer melt seasons (2012 and 2013). We have estimated the transit time of polluted melt-water through the glacier by dye-trace experiments. We have assessed the potential of biodegradation by microorganisms and we monitor possible eco-hydrological effects in streams and lakes. Results will be used to estimate the full recovery time of the glacier and pro-glacial environment. This project provides a unique opportunity to formulate and test critical hypotheses regarding hydrocarbon spreading in a polar environment. We are today surprisingly unprepared to answer the basic question on how such pristine environments are influenced by hydrocarbon pollution. However, with the increasing pressures in polar environments, there is a dire need and a rare opportunity to now create such knowledge base.

  4. Rural migration and health care

    DEFF Research Database (Denmark)

    Svendsen, Gunnar Lind Haase; Jensen, Marit Vatn

    This literature study focuses on possible links between access to health services and migration in rural areas. Why do people move to or from rural areas or why do they stay? What determines where people settle? And, in this context, do local health care services play an important or minor role, or...... no role at all? First, the paper reports on key findings from rural migration studies, in order to shed light on two migration trends: urbanization and counter-urbanization. Then we take a closer look on settlement preferences in rural areas, including the impact of health care facilities. Finally......, we end up with a more deepgoing review of the relatively small number of studies, which explicitly deal with settlement preferences related to access to health care....

  5. Neurobiology of Monarch Butterfly Migration.

    Science.gov (United States)

    Reppert, Steven M; Guerra, Patrick A; Merlin, Christine

    2016-03-11

    Studies of the migration of the eastern North American monarch butterfly (Danaus plexippus) have revealed mechanisms behind its navigation. The main orientation mechanism uses a time-compensated sun compass during both the migration south and the remigration north. Daylight cues, such as the sun itself and polarized light, are processed through both eyes and integrated through intricate circuitry in the brain's central complex, the presumed site of the sun compass. Monarch circadian clocks have a distinct molecular mechanism, and those that reside in the antennae provide time compensation. Recent evidence shows that migrants can also use a light-dependent inclination magnetic compass for orientation in the absence of directional daylight cues. The monarch genome has been sequenced, and genetic strategies using nuclease-based technologies have been developed to edit specific genes. The monarch butterfly has emerged as a model system to study the neural, molecular, and genetic basis of long-distance animal migration. PMID:26473314

  6. The International-Migration Network

    CERN Document Server

    Fagiolo, Giorgio

    2012-01-01

    This paper studies international migration from a complex-network perspective. We define the international-migration network (IMN) as the weighted-directed graph where nodes are world countries and links account for the stock of migrants originated in a given country and living in another country at a given point in time. We characterize the binary and weighted architecture of the network and its evolution over time in the period 1960-2000. We find that the IMN is organized around a modular structure characterized by a small-world pattern displaying disassortativity and high clustering, with power-law distributed weighted-network statistics. We also show that a parsimonious gravity model of migration can account for most of observed IMN topological structure. Overall, our results suggest that socio-economic, geographical and political factors are more important than local-network properties in shaping the structure of the IMN.

  7. Migrating lumbar facet joint cysts

    International Nuclear Information System (INIS)

    The majority of lumbar facet joint cysts (LFJCs) are located in the spinal canal, on the medial aspect of the facet joint with characteristic diagnostic features. When they migrate away from the joint of origin, they cause diagnostic problems. In a 7-year period we examined by computed tomography (CT) and magnetic resonance (MR) imaging five unusual cases of facet joint cysts which migrated from the facet joint of origin. Three LFJCs were identified in the right S1 foramen, one in the right L5-S1 neural foramen and one in the left erector spinae and multifidus muscles between the levels of L2-L4 spinous process. Awareness that spinal lesions identified at MRI and CT could be due to migrating facet joint cyst requires a high level of suspicion. The identification of the appositional contact of the cyst and the facet joint needs to be actively sought in the presence of degenerative facet joints. (orig.)

  8. [Intrathoracic migration of Kirschner wires].

    Science.gov (United States)

    Veres, Lukács; Kiss, Regina; Boros, Miklós; Enyedi, Attila; Takács, István; Kollár, Sándor; Damjanovich, László; Sz Kiss, Sándor

    2009-12-01

    Orthopedic surgeons apply metallic pins to stabilize the clavicule and humerus on a daily basis. Migration of these pins into the thoracic cavity is rare. We present the case of an elderly female patient, whose right humeroscapular joint was fixed with Kirschner wires due to recurrent luxation. Six weeks later, a follow-up X-ray revealed that the pins have migrated into the right thoracic cavity, confirmed by a CT chest. Videothoracoscopic removal of the metallic pins was not possible because of dense adhesions. Right anterolateral thoracotomy was carried out, and after pneumolysis one pin was taken out from the 2nd lung segment. The other one, which was running along the cupola and entering the spinal cord, was also removed. There was no postoperative surgical complication. The authors review the literature of this rare complication and point out that pins migrating into the thoracic cavity should be removed to avoid life threatening complications. PMID:19945939

  9. Rheology and migration in colloidal and noncolloidal suspensions

    Science.gov (United States)

    Morris, Jeffrey

    2013-03-01

    Suspensions of solid particles in liquids provide a useful setting for development of continuum description of particle-laden fluids. These mixtures can be made density matched, so that the volume fraction is freely variable, and the rheology can be measured in standard rheometric apparatus. This work will describe the rheology of concentrated suspensions and its implications in continuum description of the bulk flow of the mixture; the development will focus on colloidal suspensions where Brownian motion is relevant, with the limit of strong shear taken to describe noncolloidal suspensions. The normal stress response of these suspensions will be shown to be critical to description of the migration of the particles, leading to strong concentration gradients. The normal stress differences as well as the isotropic normal stress of the particle phase, or nonequilibrium osmotic pressure, will be described and related to these migration phenomena. The implications of the normal stress differences in secondary flow generation will also be described.

  10. Using supercritical fluids to refine hydrocarbons

    Science.gov (United States)

    Yarbro, Stephen Lee

    2015-06-09

    A system and method for reactively refining hydrocarbons, such as heavy oils with API gravities of less than 20 degrees and bitumen-like hydrocarbons with viscosities greater than 1000 cp at standard temperature and pressure, using a selected fluid at supercritical conditions. A reaction portion of the system and method delivers lightweight, volatile hydrocarbons to an associated contacting unit which operates in mixed subcritical/supercritical or supercritical modes. Using thermal diffusion, multiphase contact, or a momentum generating pressure gradient, the contacting unit separates the reaction products into portions that are viable for use or sale without further conventional refining and hydro-processing techniques.

  11. Volatilisation of aromatic hydrocarbons from soil

    DEFF Research Database (Denmark)

    Lindhardt, B.; Christensen, T.H.

    The non-steady-state fluxes of aromatic hydrocarbons were measured in the laboratory from the surface of soils contaminated with coal tar Four soil samples from a former gasworks site were used for the experiments. The fluxes were quantified for 11 selected compounds, 4 mono- and 7 polycyclic...... aromatic hydrocarbons, for a period of up to 8 or 16 days. The concentrations of the selected compounds in the soils were between 0.2 and 3,100 mu g/g. The study included the experimental determination of the distribution coefficient of the aromatic hydrocarbons between the sorbed phase and the water under...

  12. Biodegradation of hydrocarbons from a refinery spill

    International Nuclear Information System (INIS)

    The biodegradation of several crude oil wastes from an oil refinery spill, was studied. Crude oil was spilled onto soil; with time, only the higher boiling point hydrocarbons remained as residue. Samples of this highly weathered hydrocarbon mixture were suspended in water to which Finasol OSR 51 dispersant was added in order to enhance dispersion. Also, certain microorganisms and a degradation accelerator, were both added to accelerate degradation. Each compound was identified by CG/FID. Daily records were kept of the concentration of hydrocarbons, and the percent degradation. Tables showing the degradation percentages achieved by each compound of the crude left over after several days, are included. 4 refs., tabs., 1 fig

  13. Waste Plastic Converting into Hydrocarbon Fuel Materials

    Energy Technology Data Exchange (ETDEWEB)

    Sarker, Moinuddin; Mamunor Rashid, Mohammad; Molla, Mohammad

    2010-09-15

    The increased demand and high prices for energy sources are driving efforts to convert organic compounds into useful hydrocarbon fuels. Although much of this work has focused on biomass, there are strong benefits to deriving fuels from waste plastic material. Natural State Research Inc. (NSR) has invented a simple and economically viable process to decompose the hydrocarbon polymers of waste plastic into the shorter chain hydrocarbon of liquid fuel (patent pending). The method and principle of the production / process will be discussed. Initial tests with several widely used polymers indicate a high potential for commercialization.

  14. The Relationship between Ethnic Diversity and Classroom Disruption in the Context of Migration Policies

    Science.gov (United States)

    Veerman, Gert-Jan M.

    2015-01-01

    This paper studies the relationship between ethnic school composition and classroom disruption in secondary education in the context of migration policies. We measured classroom disruption using students' reports from 3533 schools in 20 countries provided by cross-national PISA (Programme for International Student Assessment) 2009 data. We…

  15. Rural migration in southern Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Mosser, D.; Soden, D.L.

    1993-08-01

    This study reviews the history of migration in two rural counties in Southern Nevada. It is part of a larger study about the impact of a proposed high-level nuclear waste repository on in- and out-migration patterns in the state. The historical record suggests a boom and bust economic cycle has predominated in the region for the past century creating conditions that should be taken into account by decision makers when ascertaining the long-term impacts of the proposed repository.

  16. Rural migration in southern Nevada

    International Nuclear Information System (INIS)

    This study reviews the history of migration in two rural counties in Southern Nevada. It is part of a larger study about the impact of a proposed high-level nuclear waste repository on, in and out-migration patterns in the state. The historical record suggests a boom and bust economic cycle has predominated in the region for the past century creating conditions that should be taken into account, by decision makers, when ascertaining the long-term impacts of the proposed repository

  17. The migration transition in Malaysia.

    Science.gov (United States)

    Lim, L L

    1996-01-01

    "Exploring the unique experience of migration transition in Malaysia, this paper identifies the turning points in relation to the level and nature of economic and labor market developments in Malaysia. Examining the development dynamics that mark the passage from exporting labor to depending on foreign labor, the paper concludes that such dynamics are influenced not only by economic but also sociocultural, demographic and policy factors. Several lessons from the Malaysian experience are drawn at the end to be utilized by other countries that still have to reach the turning points of the migration transition." PMID:12320775

  18. Automation of Flexible Migration Workflows

    Directory of Open Access Journals (Sweden)

    Dirk von Suchodoletz

    2011-03-01

    Full Text Available Many digital preservation scenarios are based on the migration strategy, which itself is heavily tool-dependent. For popular, well-defined and often open file formats – e.g., digital images, such as PNG, GIF, JPEG – a wide range of tools exist. Migration workflows become more difficult with proprietary formats, as used by the several text processing applications becoming available in the last two decades. If a certain file format can not be rendered with actual software, emulation of the original environment remains a valid option. For instance, with the original Lotus AmiPro or Word Perfect, it is not a problem to save an object of this type in ASCII text or Rich Text Format. In specific environments, it is even possible to send the file to a virtual printer, thereby producing a PDF as a migration output. Such manual migration tasks typically involve human interaction, which may be feasible for a small number of objects, but not for larger batches of files.We propose a novel approach using a software-operated VNC abstraction layer in order to replace humans with machine interaction. Emulators or virtualization tools equipped with a VNC interface are very well suited for this approach. But screen, keyboard and mouse interaction is just part of the setup. Furthermore, digital objects need to be transferred into the original environment in order to be extracted after processing. Nevertheless, the complexity of the new generation of migration services is quickly rising; a preservation workflow is now comprised not only of the migration tool itself, but of a complete software and virtual hardware stack with recorded workflows linked to every supported migration scenario. Thus the requirements of OAIS management must include proper software archiving, emulator selection, system image and recording handling. The concept of view-paths could help either to automatically determine the proper pre-configured virtual environment or to set up system images for certain migration workflows. View-paths may rise in demand, as the generation of PDF output files from Word Perfect input could be cached as pre-fabricated emulator system images. The current groundwork provides several possible optimizations, such as using the automation features of the original environments.

  19. New migration needs a NEMP (a new European migration policy)

    OpenAIRE

    Straubhaar, Thomas

    2000-01-01

    In nahezu allen Ländern der EU öffnet sich eine Schere zwischen den Zielen einer nationalen Migrationspolitik und den tatsächlichen Ergebnissen. Der entscheidende Grund für dieses Versagen liegt im faktischen Kompetenzverlust, den Nationalstaaten erlitten haben. Sie glauben zwar, Migration regulieren zu können. Tatsächlich aber finden Einwanderungswillige Alternativen, um ihr Ziel zu erreichen. Wird die Fronttür der legalen Wirtschaftsmigration geschlossen, drängen Menschen durch die Seitenpf...

  20. [International migration in the Americas: intraregional migration grows].

    Science.gov (United States)

    Zlotnik, H

    1992-01-01

    The principal destinations for intraregional migrants in South America in recent decades have been Argentina, Brazil, and Venezuela, while in North America the U.S. has exerted a growing attraction since 1965. Intraregional migration in Latin America has been irregular and difficult to quantify, and reliable statistics on migratory flows are nonexistent. Census data indicate that most migration to Argentina and Brazil occurred before 1960, while most migration to Venezuela occurred during the 1970s. Between 1960 and 1980, the proportion of migrants from other Latin American countries showed a tendency to increase, despite decreases in the overall level of immigration. The effect of the economic crisis of the 1980s on immigration from Latin American countries will become more apparent as census data for the 1990s become available. Selectivity according to country of origin is an important characteristic of intraregional migration in South America. The U.S. has, however, been the principal destination of Latin American migrants for the past three decades. Between 1965 and 1991 the U.S. granted resident status to more than 7.4 million persons of Latin American and Caribbean origin, and they constituted 47% of immigrants during those years. The great majority of the Latin American immigrants in the U.S. are Mexican. The 3.5 million Mexicans admitted to the U.S. as immigrants between 1965 and 1991 accounted for 22% of all immigrants during this period. PMID:12158068

  1. Migrations et relations internationales Migration and international relations. The pitfalls of managing international migration multilaterally

    Directory of Open Access Journals (Sweden)

    Hélène Thiollet

    2010-12-01

    Full Text Available Les migrations internationales sont aujourd’hui un des enjeux majeurs de la gouvernance globale. Elles restent pourtant l’objet de politiques régaliennes où dominent les accords bilatéraux sans que s’impose un régime de gestion multilatéral. Les migrations sont une des pierres d’achoppement du multilatéralisme et leur gestion est revendiquée par les États comme une dimension inaliénable de leur souveraineté (économique, territoriale…. Les institutions multilatérales tentent de proposer des modalités de gouvernance multilatérale des migrations comme phénomène social global. À l’Onu, le Haut commissariat aux réfugiés (Hcr s’occupe des réfugiés et l’Organisation internationale du travail (Oit des migrants en leur qualité de travailleurs. La Banque mondiale et le Fmi sont particulièrement actifs sur la question des migrations et des transferts financiers qui les accompagnent alors que l’Unicef s’intéresse aux conséquences sociales de la mobilité sur les familles dans les pays d’origine ou d’accueil. L’Organisation internationale des migrations travaille quant à elle en marge de l’Onu. L’Onu n’est pas parvenu à imposer la Convention sur les droits des migrants de 1990 et ne parvient pas à faire émerger une ligne d’action collective dans l’arène multilatérale sur la question migratoire. Pourtant, dans la sphère onusienne et au-delà, les organisations internationales négocient l’émergence d’une agence spécialisée dans les migrations. À partir de la stratégie historique du Hcr dans le champ multilatéral et d’une innovation juridique récente – le concept de « migrations mixtes » –, on décrit une des tentatives de gestion juridique de la mobilité forcée et volontaire. En 2006, le concept émerge avec l’expérience des migrations sub-sahariennes à travers la Méditerranée. On s’intéresse ici à son utilisation dans le cas de migrations depuis la corne de l’Afrique vers le Yémen. Le concept de « migrations mixtes » permet d’observer les prémisses de la remise en question de la partition entre réfugiés et migrants économiques. Cette analyse nous permet de mettre en lumière les apories contemporaines des conditions juridiques et statutaires de la mobilité et les réponses pragmatiques qui y sont apportées. À partir de sa compétence de terrain sur les populations réfugiées et d’innovation organisationnelles récentes, le Hcr se positionne dans le champ politique international comme gestionnaire potentiel de la mobilité internationale face à l’Oit ou à une agence non-onusienne comme l’Oim.Today, one of the biggest issues facing global governance is international migration. It is nevertheless dominated by national policy and bilateral agreements, and lacks a multilateral management system. Indeed, migration is one of the stumbling blocks of multilateralism, because most countries consider migration management is key to national sovereignty (in economic and territorial terms. Multilateral institutions attempt to suggest multilateral migration governance mechanisms as a global social phenomenon. At the UN, the High Commission on Refugees (UNHCR was created to deal with refugee issues, and the International Labour Organisation (ILO for migrant workers. The World Bank and the International Monetary Fund (IMF are very active in issues affecting migrants and remittances, while UNICEF focuses on the social consequences of this mobility on families in home and host countries. The International Organisation for Migration (IOM works on the fringes of the UN. The UN was unable to impose the Convention on the Rights of Migrants in 1990, and has had difficulty in developing a joint programme of action for the multilateral management of migration. Nevertheless, on the UN level and above, international organisations are negotiating the creation of an agency specialising in migration. Using the HCR’s past multilateral strategy and a recent legal innovation – the concept of mixed migration – we describe a legal attempt to manage forced and voluntary mobility. “Mixed migration” first appeared in 2006 to describe Sub-Saharan migration through the Mediterranean region. We examine how it is applied to migrant flows from the Horn of Africa to Yemen. The concept of mixed migration can be used to observe the ways in which the difference between refugees and economic migrants are being broken down. This highlights the pitfalls in the legal and statutory conditions affecting mobility, and the practical solutions put forward to overcome this situation. With its experience in dealing with refugee populations and recent organisational innovations, the UNHCR seems better placed than the ILO or the IOM to manage international mobility in the global political context.

  2. THE MIGRATION OF GAP-OPENING PLANETS IS NOT LOCKED TO VISCOUS DISK EVOLUTION

    International Nuclear Information System (INIS)

    Most standard descriptions of Type II migration state that massive, gap-opening planets must migrate at the viscous drift rate. This is based on the idea that the disk is separated into an inner and outer region and gas is considered unable to cross the gap. In fact, gas easily crosses the gap on horseshoe orbits, nullifying this necessary premise which would set the migration rate. In this work, it is demonstrated using highly accurate numerical calculations that the actual migration rate is dependent on disk and planet parameters, and can be significantly larger or smaller than the viscous drift rate. In the limiting case of a disk much more massive than the secondary, the migration rate saturates to a constant that is sensitive to disk parameters and is not necessarily of the order of the viscous rate. In the opposite limit of a low-mass disk, the migration rate decreases linearly with disk mass. Steady-state solutions in the low disk mass limit show no pile-up outside the secondary's orbit, and no corresponding drainage of the inner disk

  3. Scattering and; Delay, Scale, and Sum Migration

    Energy Technology Data Exchange (ETDEWEB)

    Lehman, S K

    2011-07-06

    How do we see? What is the mechanism? Consider standing in an open field on a clear sunny day. In the field are a yellow dog and a blue ball. From a wave-based remote sensing point of view the sun is a source of radiation. It is a broadband electromagnetic source which, for the purposes of this introduction, only the visible spectrum is considered (approximately 390 to 750 nanometers or 400 to 769 TeraHertz). The source emits an incident field into the known background environment which, for this example, is free space. The incident field propagates until it strikes an object or target, either the yellow dog or the blue ball. The interaction of the incident field with an object results in a scattered field. The scattered field arises from a mis-match between the background refractive index, considered to be unity, and the scattering object refractive index ('yellow' for the case of the dog, and 'blue' for the ball). This is also known as an impedance mis-match. The scattering objects are referred to as secondary sources of radiation, that radiation being the scattered field which propagates until it is measured by the two receivers known as 'eyes'. The eyes focus the measured scattered field to form images which are processed by the 'wetware' of the brain for detection, identification, and localization. When time series representations of the measured scattered field are available, the image forming focusing process can be mathematically modeled by delayed, scaled, and summed migration. This concept of optical propagation, scattering, and focusing have one-to-one equivalents in the acoustic realm. This document is intended to present the basic concepts of scalar scattering and migration used in wide band wave-based remote sensing and imaging. The terms beamforming and (delayed, scaled, and summed) migration are used interchangeably but are to be distinguished from the narrow band (frequency domain) beamforming to determine the direction of arrival of a signal, and seismic migration in which wide band time series are shifted but not to form images per se. Section 3 presents a mostly graphically-based motivation and summary of delay, scale, and sum beamforming. The model for incident field propagation in free space is derived in Section 4 under specific assumptions. General object scattering is derived in Section 5 and simplified under the Born approximation in Section 6. The model of this section serves as the basis in the derivation of time-domain migration. The Foldy-Lax, full point scatterer scattering, method is derived in Section 7. With the previous forward models in hand, delay, scale, and sum beamforming is derived in Section 8. Finally, proof-of-principle experiments are present in Section 9.

  4. Influences of environmental cues, migration history and habitat familiarity on partial migration

    DEFF Research Database (Denmark)

    Skov, Christian; Aarestrup, Kim; Baktoft, Henrik; Brodersen, Jakob; Brönmark, Christer; Hansson, Lars-Anders; Eg Nielsen, Einar; Nielsen, Tine; Nilsson, Anders

    2010-01-01

    The factors that drive partial migration in organisms are not fully understood. Roach (Rutilus rutilus), a freshwater fish, engage in partial migration where parts of populations switch between summer habitats in lakes and winter habitats in connected streams. To test if the partial migration trait...... is phenotypically plastic or has genetic components, we translocated roach from 2 populations with different opportunities for migration to a lake with migration opportunity, containing a local roach population. This enabled monitoring of partial migration of fish in 3 different situations: 1......) previous opportunity for migration, migrating in a familiar environment (the local population); 2) previous opportunity for migration, migrating in an unfamiliar environment; and 3) no previous opportunity for seasonal migration, migrating in an unfamiliar environment. In addition, we evaluated the...

  5. The application of geomembranes for controlling diffusive migration of hydrocarbons in cold region environments

    Energy Technology Data Exchange (ETDEWEB)

    McWatters, R. [Queen' s Univ., Kingston, ON (Canada). Dept. of Civil Engineering; Rutter, A. [Queen' s Univ., Kingston, ON (Canada). School of Environmental Studies; Rowe, R.K. [Queen' s Univ., Kingston, ON (Canada). Dept. of Civil Engineering, Geoengineering Centre

    2010-07-01

    Geomembranes are often used in the design of landfills, barriers, or biopiles in cold regions. This study was conducted to assess the performance of a geomembrane in cold weather. The partitioning, diffusion, and permeation coefficients 5 geomembranes were investigated in a series of diffusion and sorption tests. Benzene, toluene, ethylbenzenes, and xylenes were used as source contaminants over a temperature range of 2 to 24 degrees C on a 0.53 mm linear low density polyethylene (LLDPE) geomembrane; a 1.5 mm high density polyethylene HDPE geomembrane; and a 0.53 mm co-extruded LLDPE geomembrane with an ethylene vinyl alcohol EVOH inner core. The effect of exposure to cold climates and freeze-thaw cycles on the ability of the membranes to act as diffusive barriers to contaminants was investigated. Results of the study showed that the EVOH co-extruded geomembrane had the lowest permeation coefficients. An HDPE samples recovered from a test plot at an Arctic landfill showed that the aged geomembrane had similar partitioning, diffusion and permeation values as the unexposed geomembrane.

  6. Understanding SOA Migration Using a Conceptual Framework

    Directory of Open Access Journals (Sweden)

    Maryam Razavian

    2010-07-01

    Full Text Available Migration of legacy assets to SOA embodies a key software engineering challenge. Over a decade there has been an increasing interest in the approaches addressing SOA migration. These approaches mainly differ in `what is migrated' and `how the migration is performed'. Such differences aggravate achieving a general understanding of `what SOA migration entails'. We describe what such migration process entails and what distinct conceptual elements systematically define the process. Based on the comprising conceptual elements the framework which is considered as a basis for understanding and assessment of different approaches is proposed. Further, the role of the migration framework in positioning and assessing the existing methods, is discussed. Finally, the procedure for positioning and mapping of migration approaches on the framework is explained using two example migration processes.

  7. Teaching secondary mathematics

    CERN Document Server

    Rock, David

    2013-01-01

    Solidly grounded in up-to-date research, theory and technology,?Teaching Secondary Mathematics?is a practical, student-friendly, and popular text for secondary mathematics methods courses. It provides clear and useful approaches for mathematics teachers, and shows how concepts typically found in a secondary mathematics curriculum can be taught in a positive and encouraging way. The thoroughly revised fourth edition combines this pragmatic approach with truly innovative and integrated technology content throughout. Synthesized content between the book and comprehensive companion websi

  8. Canine Secondary Glaucomas.

    Science.gov (United States)

    Pumphrey, Stephanie

    2015-11-01

    Secondary glaucomas are common in dogs, and occur due to obstruction of aqueous humor flow at the pupil, iridocorneal angle, or trabecular meshwork by numerous mechanisms. Secondary glaucoma is suspected based on examination findings, or presence of elevated IOP in an animal with a signalment inconsistent with primary glaucoma. Animals with secondary glaucoma require more diagnostic testing than animals with primary glaucoma. Management is challenging, and treatments used for primary glaucoma may be ineffective or even detrimental. Prognosis for vision and/or globe retention may be better than for primary glaucoma, particularly if underlying causes can be found and addressed promptly. PMID:26319444

  9. Migration from and to Palestine from a gender perspective: results from the Migration Survey – 2010

    OpenAIRE

    Duraidi, Mohammed

    2011-01-01

    Migration has gained in importance in recent years due to significantly increased migration rates, in addition to the effect of migration on various population structures such as age, gender and marital status in both sending and receiving countries. This paper aims to look at the recent patterns of migration from and to the occupied Palestinian territory (oPt) in terms of size, characteristics, remittances, migration determinants, return migration, etc. To this objective, data ha...

  10. 21 CFR 172.882 - Synthetic isoparaffinic petroleum hydrocarbons.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Synthetic isoparaffinic petroleum hydrocarbons. 172... hydrocarbons. Synthetic isoparaffinic petroleum hydrocarbons may be safely used in food, in accordance with the... liquid hydrocarbons meeting the following specifications: Boiling point 93-260 °C as determined by...

  11. 21 CFR 178.3530 - Isoparaffinic petroleum hydrocarbons, synthetic.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Isoparaffinic petroleum hydrocarbons, synthetic... hydrocarbons, synthetic. Isoparaffinic petroleum hydrocarbons, synthetic, may be safely used in the production... isoparaffinic petroleum hydrocarbons, produced by synthesis from petroleum gases consist of a mixture of...

  12. 40 CFR 86.317-79 - Hydrocarbon analyzer specifications.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Hydrocarbon analyzer specifications....317-79 Hydrocarbon analyzer specifications. (a) Hydrocarbon measurements are to be made with a heated... measures hydrocarbon emissions on a dry basis is permitted for gasoline-fueled testing; Provided,...

  13. Labour Force Migration Effects within European Union

    Directory of Open Access Journals (Sweden)

    Carmen Mihaela Tudorache

    2006-10-01

    Full Text Available Within the EU, there is no common policy on migration; there are common policies on certain aspects of migration. The Member States fear of migration, but their economies and societies will further need migrant workers. Labour force migration have positive, but also negative consequences for all parties involved: receiving countries, origin countries and migrant workers. Within this framework, a common approach of the migration management and the harmonization of the economic migration policies of the Member States represent already one of the most important challenges for the European Union and will be further emphasized.

  14. Secondary Qualities in Retrospect.

    Directory of Open Access Journals (Sweden)

    Tim De Mey

    2001-01-01

    Full Text Available Although the importance, both historically and systematically, of the seventeenth century distinction between primary and secondary qualities is commonly recognised, there is no consensus on its exact nature. Apparently, one of the main difficulties in its interpretation is to tell the constitutive from the argumentative elements. In this paper, we focus on the primary-secondary quality distinctions drawn by Boyle and Locke. We criticise, more specifically, MacIntosh?s analysis of them. On the one hand, MacIntosh attributes too many different primary-secondary quality distinctions to Boyle and Locke. On the other hand, he forbears to attribute a particular primary-secondary quality distinction to them, which, at least in the case of Boyle, differs genuinely from his main distinction between the mechanical affections of matter and all of matter?s other qualities.

  15. Nitrocarburizing in ammonia-hydrocarbon gas mixtures

    DEFF Research Database (Denmark)

    Pedersen, Hanne; Christiansen, Thomas; Somers, Marcel A. J.

    2011-01-01

    The present work investigates the possibility of nitrocarburising in ammonia-acetylene-hydrogen and ammonia-propene-hydrogen gas mixtures, where unsaturated hydrocarbon gas is the carbon source during nitrocarburising. Consequently, nitrocarburising is carried out in a reducing atmosphere and...

  16. Nitrocarburising in ammonia-hydrocarbon gas mixtures

    DEFF Research Database (Denmark)

    Pedersen, Hanne; Christiansen, Thomas; Somers, Marcel A. J.

    The present work investigates the possibility of nitrocarburising in ammonia-acetylene-hydrogen and ammoniapropene- hydrogen gas mixtures, where unsaturated hydrocarbon gas is the carbon source during nitrocarburising. Consequently, nitrocarburising is carried out in a reducing atmosphere and...

  17. Quantitative Hydrocarbon Energies from the PMO Method.

    Science.gov (United States)

    Cooper, Charles F.

    1979-01-01

    Details a procedure for accurately calculating the quantum mechanical energies of hydrocarbons using the perturbational molecular orbital (PMO) method, which does not require the use of a computer. (BT)

  18. An Acid Hydrocarbon: A Chemical Paradox

    Science.gov (United States)

    Burke, Jeffrey T.

    2004-01-01

    The chemical paradox of cyclopentadiene, a hydrocarbon, producing bubbles like a Bronsted acid is observed. The explanation that it is the comparative thermodynamic constancy of the fragrant cyclopentadienyl anion, which produces the powerful effect, resolves the paradox.

  19. MICROEMULSION FORMATION WITH MIXED CHLORINATED HYDROCARBON LIQUIDS

    Science.gov (United States)

    Mixing rules for water/chlorocarbon/anionic-surfactant systems have been studied. t was found that the behavior of chlorocarbons parallels the ideal mixing rules for hydrocarbons. he polarity of some chlorocarbons prevented a direct determination of electrolyte concentration and ...

  20. NIST Hydrocarbon Spectral Database - SRD 115

    Data.gov (United States)

    National Institute of Standards and Technology, Department of Commerce — This database contains the rotational spectral lines observed and reported in the open literature for 91 hydrocarbon molecules through September 1987. The isotopic...

  1. BIOREMEDIATED SOIL VENTING OF LIGHT HYDROCARBONS

    Science.gov (United States)

    The effectiveness and feasibility of bioremediated soil venting of light hydrocarbons in the unsaturated zone was investigated. Degradation mechanics were considered as a one dimensional balance of storage, linear sorption, vertical advection, and Michaelis-Menton kinetics. he re...

  2. Collision data involving hydro-carbon molecules

    International Nuclear Information System (INIS)

    Hydro-carbon molecules are abundantly produced when graphites are used as internal wall materials of hydrogen plasmas and strongly influence properties of low temperature plasmas near the edges as well as those of high temperature plasmas at the center. In this report, following simple description of the production mechanisms of hydro-carbon molecules under the interactions between graphite and hydrogen plasma, the present status of collision data for hydro-carbon molecules by electron impact is discussed and the relevant data are summarized in a series of figures and tables. It should also be noted that, in addition to fusion plasmas, these hydrocarbon data compiled here are quite useful in other applications such as plasma chemistry and material processing. (author)

  3. Using microorganisms to aid in hydrocarbon degradation

    International Nuclear Information System (INIS)

    Aliphatic hydrocarbons are threatening the potable water supply and the aquatic ecosystem. Given the right microbial inhabitant(s), a large portion of these aliphatic hydrocarbons could be biodegraded before reaching the water supply. The authors' purpose is to isolate possible oil-degrading organisms. Soil samples were taken from hydrocarbon-laden soils at petroleum terminals, a petroleum refinery waste-treatment facility, a sewage-treatment plant grease collector, a site of previous bioremediation, and various other places. Some isolates known to be good degraders were obtained from culture collection services. These samples were plated on a 10w-30 multigrade motor oil solid medium to screen for aliphatic hydrocarbon degraders. The degrading organisms were isolated, identified, and tested (CO2 evolution, BOD, and COD) to determine the most efficient degrader(s). Thirty-seven organisms were tested, and the most efficient degraders were Serratia marcescens, Escherichia coli, and Enterobacter agglomerans

  4. The migration of university graduates

    DEFF Research Database (Denmark)

    Drejer, Ina; Holm, Jacob Rubæk; Nielsen, Kristian

    of university graduates is an important issue for regional policy makers. The present paper analyzes the migration patterns of university graduates from two very different regions in Denmark: the Greater Capital region around Copenhagen and the peripheral region of North Denmark. Studies of the...

  5. Clocks, cryptochromes and Monarch migrations

    OpenAIRE

    Kyriacou, Charalambos P.

    2009-01-01

    The annual migration of the Monarch butterfly (Danaus plexippus) from eastern North America to central Mexico is one of nature's most inspiring spectacles. Recent studies including one in BMC Biology, have begun to dissect the molecular and neurogenetic basis for this most complex behavior.

  6. Material migration in divertor tokamaks

    International Nuclear Information System (INIS)

    Erosion of plasma facing material, its transport through the plasma and its deposition define the topic of material migration. It is a subject which is a pivotal issue both for ITER and for the longer term economic and technological viability of fusion power. This review summarises the current status and future direction of this field

  7. International Adoptions: The Quiet Migration.

    Science.gov (United States)

    Weil, Richard H.

    1984-01-01

    Examines patterns in the international migration of children for adoption since World War II, with emphasis on those going to Sweden, the United Kingdom, and the United States. Relates findings to political and cultural factors. Observes that Latin America became a major source area for the United States in the 1970s, but that Asia remained…

  8. Les questions de migrations internationales

    Science.gov (United States)

    Samman, Mouna Liliane

    1993-03-01

    International migrations have growing implications for both countries of origin and countries of destination. In the latter, the presence of foreigners and of members of their families today creates problems of integration, causes argument and brings mounting xenophobia. Paralleling political, economic and social measures taken by public authorities to respond to these difficulties, education needs to assist in defusing the resulting social tensions by preparing the minds of learners and helping to develop new attitudes. In particular, when educational programmes address questions of international migration, these should be treated in the framework of historical evolution so that their real significance and their true temporal and spatial dimensions become apparent. It is also important that the growing interdependence between countries should be made plain, that national history should be placed in its international context, and that the true consequences of these developments should be made clear. In this context, learners need to be acquainted with Human Rights, thereby stressing universal moral values and the role of the individual. Lastly, questions relating to international migration are usually presented in the media in a selective and partial manner, and the young people who take in this information often accept the hasty judgments which are made of situations as proven facts. This is why all teaching about international migration needs to be considered or reconsidered in the light of the complementary or competing actions of the media.

  9. Lymphocyte migration studies in man

    International Nuclear Information System (INIS)

    In this paper the author outlines what is known of the migration and recirculation of the lymphocyte in man and animals. He then attempts to demonstrate how a better grasp of these phenomena may contribute to an understanding of the pathophysiology of human diseases such as chronic lymphocytic leukemia, non-Hodgkin's lymphomas, Hodgkin's, and other diseases

  10. Floodplain heterogeneity and meander migration

    Science.gov (United States)

    The impact of horizontal heterogeneity of floodplain soils on rates and patterns of meander migration is analyzed with a Ikeda et al. (1981)-type model for hydrodynamics and bed morphodynamics, coupled with a physically-based bank erosion model according to the approach developed by Motta et al. (20...

  11. Native vacancy migrations in zircon

    International Nuclear Information System (INIS)

    Energy minimization methods were used to simulate the migration of Zr, Si, and O vacancies in zircon (ZrSiO4). Two sets of interatomic potentials were employed for comparison: one with O-Si-O three-body terms for the SiO4, and one without. Results for Si were inconclusive, but consistent with maintaining the integrity of the SiO4 molecular units. Both Zr and O vacancies can migrate on three-dimensional sublattice networks, thus supporting the experimentally observed diffusional isotropy. The predicted Zr vacancy migration energy (1.16-1.38 eV) was in good agreement with experiment if supplemented by Zr vacancy formation via Schottky or Frenkel defects (6.21-12.28 eV/defect). Oxygen vacancy migration energies were predicted to be 0.99-1.16 eV, somewhat lower than the experimental value of 4.64 eV measured in natural zircons, which thus may include significant contributions from vacancy formation mechanisms at 3.31-6.52 eV/defect. (orig.)

  12. Job Migration: A Collaborative Effort

    Science.gov (United States)

    Wagoner, Cynthia L.

    2012-01-01

    Music teachers often change jobs several times during their careers. Reasons for job changes vary, but regardless, these changes bring a different set of challenges. Sharing knowledge and learning are part and parcel of collaboration. So what if, as education professionals, music teachers decided to collaborate during job migrations? For all music…

  13. Long migration flights of birds

    International Nuclear Information System (INIS)

    The extremely long migration flights of some birds are carried out in one hop, necessitating a substantial prior build-up of fat fuel. We summarize the basic elements of bird flight physics with a simple model, and show how the fat reserves influence flight distance, flight speed and the power expended by the bird during flight. (paper)

  14. A Psychological Journey Through Migration

    OpenAIRE

    Maria Inês Dias Silva

    2014-01-01

    Psychological dimension is emphasized in different approaches and languages over migration in a review of its reasons and circumstances, analyzing the person “decontextualization”, his rupture, the transcultural risk and the migratory trauma that may occur. The concept of disease and illness are mentioned as well as the concept of “alterity”, the cultural dimension in the therapeutic relation and specific addressing techniques.

  15. A Psychological Journey Through Migration

    Directory of Open Access Journals (Sweden)

    Maria Inês Dias Silva

    2014-10-01

    Full Text Available Psychological dimension is emphasized in different approaches and languages over migration in a review of its reasons and circumstances, analyzing the person “decontextualization”, his rupture, the transcultural risk and the migratory trauma that may occur. The concept of disease and illness are mentioned as well as the concept of “alterity”, the cultural dimension in the therapeutic relation and specific addressing techniques.

  16. Liquid chromatography in migration studies

    International Nuclear Information System (INIS)

    Liquid chromatography ahs been suggested as a facile experimental technique to determine important physico-chemical properties, as permeability, porosity, dispersion-, diffusion-, and sorption charcteristics for geological material as chalk samples. The feasibility of the trechnique as a rapid method to evaluate the possible influence of changes in ground water composition on the migration behavior of radionuclides has been demonstrated

  17. Tritium migration in tritiated anisole

    International Nuclear Information System (INIS)

    Experimental studies have been reported of reactions involving the phenyl cation as an intermediate where the results obtained are most easily explained in terms of 1,2 hydrogen shifts in the intermediate ion. Our purpose here is to present an alternative interpretation, supported by MINDO/3 calculations, that avoids the implied conclusion that the barrier to hydrogen migration is in fact small

  18. MANDARIN SECONDARY PREDICATES

    OpenAIRE

    Ryosuke Shibagaki

    2010-01-01

    In the first part, I provide some data of secondary predicates in English and Mandarin on consequence-depictives (SUBJ-oriented) and resultatives (OBJ-oriented), which adopt an intransitive verb/adjective for their secondary predicate. In the second half, I present an account of the linking issue on “resultative” compound predicates in Mandarin Chinese, building on the LFG/LMT work of Her (2007), who assumed that the argument structures of each predicate merge to give a composite structure, w...

  19. [Haitian migration to Santo Domingo].

    Science.gov (United States)

    Latortue, P R

    1985-01-01

    This work examines the history of Haitian migration to the Dominican Republic, the central role of Haitian migration in Dominican society, working conditions of Haitian migrants in the Dominican Republic, and the relationship of the migration to economic development on the island of Hispaniola. Lack of data, the difficulty of measuring illegal movement, and the problem of defining Haitians in Santo Domingo have impeded understanding of migration to the Dominican Republic. It is believed by many authorities that Haitian migration to Santo Domingo is considerable and perhaps exceeds that to the US. Haitian migration to the Dominican Republic began after 1915 with the fall of the Haitian president, a worsening of economic conditions partly caused by stagnation in the agricultural sector, and the newly dominant role of the US in Haitian economic affairs. The Great Depression of the 1930s was a direct antecedent of the massacre of Haitians by Dominican police in which some 30 thousand persons were killed; the economic recession of the early 1980s has also caused an outburst of antiHaitian feeling in the Dominican Republic although 80% of laborers in the sugar industry are Haitians. Sugar is extremely important to the Dominican economy: in 1974, sugar covered 12% of cultivated land, produced 40% of foreign exchange earnings, and was responsable for 21% of taxable income. Dominicans however refuse to work in sugar plantations under the current technological. conditions and wage system. Although the government periodically demands the Dominicanization of the sugar work force, no such changes have been made. Sugar will probably continue to play a decisive role in the generation of foreign exchange despite introduction of more technologically advanced sectors which benefit from better prices in the international market. Possibilities of mechanizing sugar production in the Dominican Republic appear remote, and failure to modernize an important sector of the economy has explained migration of unskilled labor from poorer countries in more than 1 case. Under such circumstances, the extremely poor working conditions of Haitians in the Dominican Republic are not surprising. A 1983 investigation by the International Labour Organization indicated that salaries were low, that a large proportion was routinely diverted from the migrants, that hours of work were long with no regular rest and few days off, that few workers had any contractual protection, that forced labor recruitment occurred, that a rigid system of vigilance with armed patrols was used to keep the immigrants in the work camps, and that living conditions were substandard--in short, that Haitian workers were "neo-slaves". In addition, the Dominicans consider themselves racially and culturally superior to Haitians. The Haitian government, in return for payments from the Dominican Republic, does nothing to stop the abuses. PMID:12179414

  20. Synthesis and characterization of hydrocarbon sphere

    International Nuclear Information System (INIS)

    With glucose as starting material, hydrocarbon sphere which was rich in oxygen containing functional groups was synthesized by hydrothermal carbonization process, and characterized by SEM and FTIR techniques. The results show that the size and dispersion of carbon spheres depend on many factors, including the concentration of glucose, the reaction temperature and the adulterated organic monomer. The obtained hydrocarbon spheres contain rich functional groups which can greatly improve the hydrophilicity and chemical reactivity. (authors)

  1. Biodegradation of Petroleum Hydrocarbons in Soil

    OpenAIRE

    MR Mehrasbi; Haghighi, B; M. Shariat; Naseri, S.; K. Naddafi

    2003-01-01

    Biodegradation of petroleum hydrocarbons (20 g/kg dw soil) was investigated in 3 media, differing in the kind of petroleum fractions. In the laboratory experiments, during 5 months, the activities of petroleum hydrocarbon-degrading microorganisms and dehydrogenase activity of soil was determined. Gas chromatographic analysis showed the biological decontaminations for gas oil, kerosene and synthetic mixture (gas oil, kerosene and furnace oil) are 60 %, 36 % and 55 %, respectively. Dehydrogenas...

  2. Formation of hydrocarbons by bacteria and algae

    Energy Technology Data Exchange (ETDEWEB)

    Tornabene, T.G.

    1980-12-01

    A literature review has been performed summarizing studies on hydrocarbon synthesis by microorganisms. Certain algal and bacterial species produce hydrocarbons in large quantities, 70 to 80% of dry cell mass, when in a controlled environment. The nutritional requirements of these organisms are simple: CO/sub 2/ and mineral salts. The studies were initiated to determine whether or not microorganisms played a role in petroleum formation. 90 references. (DMC)

  3. Electrochemical Routes towards Sustainable Hydrocarbon Fuels

    DEFF Research Database (Denmark)

    Mogensen, Mogens Bjerg

    2012-01-01

    The potential of renewable energy and possible solution to the intermittency problem of renewable energy sources like sun and wind are explained. The densest storage of energy is in the form of hydrocarbons. The most suitable method of conversion and storage within a foreseeable future is electrolysis followed by conversion into synthetic hydrocarbons, alcohols or ethers. Several types of electrolysers exist. The various types are listed together with a short description of principle and status....

  4. Acquired and Innate Immunity to Polyaromatic Hydrocarbons

    OpenAIRE

    Yusuf, Nabiha; Timares, Laura; Seibert, Megan D; XU, HUI; Elmets, Craig A

    2006-01-01

    Polyaromatic hydrocarbons are ubiquitous environmental pollutants that are potent mutagens and carcinogens. Researchers have taken advantage of these properties to investigate the mechanisms by which chemicals cause cancer of the skin and other organs. When applied to the skin of mice, several carcinogenic polyaromatic hydrocarbons have also been shown to interact with the immune system, stimulating immune responses and resulting in the development of antigen specific T-cell mediated immunity...

  5. Birds and polycyclic aromatic hydrocarbons

    Science.gov (United States)

    Albers, P.H.

    2006-01-01

    Polycyclic aromatic hydrocarbons (PAH) are present throughout the global environment and are produced naturally and by activities of humans. Effects of PAH on birds have been determined by studies employing egg injection, egg immersion, egg shell application, single and multiple oral doses, subcutaneous injection, and chemical analysis of field-collected eggs and tissue. The four-to six-ring aromatic compounds are the most toxic to embryos, young birds, and adult birds. For embryos, effects include death, developmental abnormalities, and a variety of cellular and biochemical responses. For adult and young birds, effects include reduced egg production and hatching, increased clutch or brood abandonment, reduced growth, increased organweights, and a variety of biochemical responses. Trophic level accumulation is unlikely. Environmental exposure to PAH in areas of high human population or habitats affected by recent petroleum spills might be sufficient to adversely affect reproduction. Evidence of long-term effects of elevated concentrations of environmental PAH on bird populations is very limited and the mechanisms of effect are unclear.

  6. Deuterated polycyclic aromatic hydrocarbons: Revisited

    CERN Document Server

    Doney, Kirstin D; Mori, Tamami; Onaka, Takashi; Tielens, A G G M

    2016-01-01

    The amount of deuterium locked up in polycyclic aromatic hydrocarbons (PAHs) has to date been an uncertain value. We present a near-infrared (NIR) spectroscopic survey of HII regions in the Milky Way, Large Magellanic Cloud (LMC), and Small Magellanic Cloud (SMC) obtained with AKARI, which aims to search for features indicative of deuterated PAHs (PAD or Dn-PAH) to better constrain the D/H ratio of PAHs. Fifty-three HII regions were observed in the NIR (2.5-5 {\\mu}m), using the Infrared Camera (IRC) on board the AKARI satellite. Through comparison of the observed spectra with a theoretical model of deuterated PAH vibrational modes, the aromatic and (a)symmetric aliphatic C-D stretch modes were identified. We see emission features between 4.4-4.8 {\\mu}m, which could be unambiguously attributed to deuterated PAHs in only six of the observed sources, all of which are located in the Milky Way. In all cases, the aromatic C-D stretching feature is weaker than the aliphatic C-D stretching feature, and, in the case o...

  7. PROTONATED POLYCYCLIC AROMATIC HYDROCARBONS REVISITED

    International Nuclear Information System (INIS)

    We reconsider the contribution that singly protonated polycyclic aromatic hydrocarbons (PAHs; HPAH+s) might make to the Class A component of the 6.2 ?m interstellar emission feature in light of the recent experimental measurements of protonated naphthalene and coronene. Our calculations on the small HPAH+s have a band near 6.2 ?m, as found in experiment. While the larger HPAH+s still have emission near 6.2 ?m, the much larger intensity of the band near 6.3 ?m overwhelms the weaker band at 6.2 ?m, so that the 6.2 ?m band is barely visible. Since the large PAHs are more representative of those in the interstellar medium, our work suggests that large HPAH+s cannot be major contributors to the observed emission at 6.2 ?m (i.e., Class A species). Saturating large PAH cations with hydrogen atoms retains the 6.2 ?m Class A band position, but the rest of the spectrum is inconsistent with observed spectra.

  8. Deuterated polycyclic aromatic hydrocarbons: Revisited

    Science.gov (United States)

    Doney, K. D.; Candian, A.; Mori, T.; Onaka, T.; Tielens, A. G. G. M.

    2016-02-01

    Aims: The amount of deuterium locked up in polycyclic aromatic hydrocarbons (PAHs) has to date been an uncertain value. We present a near-infrared (NIR) spectroscopic survey of Hii regions in the Milky Way, Large Magellanic Cloud, and Small Magellanic Cloud obtained with AKARI, which aims to search for features indicative of deuterated PAHs (PAD or Dn-PAH) to better constrain the D/H ratio of PAHs. Methods: Fifty-three Hii regions were observed in the NIR (2.5-5 ?m), using the Infrared Camera (IRC) on board the AKARI satellite. Through comparison of the observed spectra with a theoretical model of deuterated PAH vibrational modes, the aromatic and (a)symmetric aliphatic C-D stretch modes were identified. Results: We see emission features between 4.4-4.8 ?m, which could be unambiguously attributed to deuterated PAHs in only six of the observed sources, all of which are located in the Milky Way. In all cases, the aromatic C-D stretching feature is weaker than the aliphatic C-D stretching feature, and, in the case of M17b, this feature is not observed at all. Based on the weak or absent PAD features in most of the observed spectra, it is suggested that the mechanism for PAH deuteration in the ISM is uncommon.

  9. Polycyclic aromatic hydrocarbons in rainwater.

    Science.gov (United States)

    Quaghebeur, D; de Wulf, E; Ravelingien, M C; Janssens, G

    1983-12-15

    A study on polycyclic aromatic hydrocarbons (PAH) in rainwater was carried out over periods of at least one year at two locations in Belgium with different environments. Maximum amounts and concentrations of PAH were reached during the winter period, mainly due to household heating. This influence was also reflected in the relative proportions of the six PAH measured. For comparable periods the amounts of PAH were almost proportional to the quantity of rain. With the available data, and as most of the rainfall is coming from the same wind direction, it was not feasible to localise possible pollution sources based upon the distribution of PAH over the different windsectors, nor was it possible to identify significant differences for both sampling locations due to their different surroundings, indicating that the rain plays an important role in the transport and distribution of pollutants over a wide area. Between about 100 and 170 micrograms m-2 PAH and 2 to 3 g m-2 of total organic carbon content (TOC) per year were deposited by the rain, corresponding to mean concentrations of about 140 ngl-1 of PAH and 2.9 mgl-1 of TOC. PMID:6665554

  10. Hydrocarbon biodegradation in hypersaline environments

    Energy Technology Data Exchange (ETDEWEB)

    Ward, D.M.; Brock, T.D.

    1978-02-01

    When mineral oil, hexadecane, and glutamate were added to natural samples of varying salinity (3.3 to 28.4 percent) from salt evaporation ponds and Great Salt Lake, Utah, rates of metabolism of these compounds decreased as salinity increased. Rate limitations did not appear to relate to low oxygen levels or to the availability of organic nutrients. Some oxidation of L-(U-/sup 14/C)glutamic acid occurred even at extreme salinities, whereas oxidation of (l-/sup 14/C)hexadecane was too low to be detected. Gas chromatographic examination of hexane-soluble components of tar samples from natural seeps at Rozel Point in Great Salt Lake demonstrated no evidence of biological oxidation of isoprenoid alkanes subject to degradation in normal environments. Some hexane-soluble components of the same tar were altered by incubation in a low-salinity enrichment culture inoculated with garden soil. Attempts to enrich for microorganisms in saline waters able to use mineral oil as a sole source of carbon and energy were successful below, but not above, about 20 percent salinity. This study strongly suggests a general reduction of metabolic rate at extreme salinities and raises doubt about the biodegradation of hydrocarbons in hypersaline environments.

  11. Hydrocarbon biodegradation in hypersaline environments.

    Science.gov (United States)

    Ward, D M; Brock, T D

    1978-02-01

    When mineral oil, hexadecane, and glutamate were added to natural samples of varying salinity (3.3 to 28.4%) from salt evaporation ponds and Great Salt Lake, Utah, rates of metabolism of these compounds decreased as salinity increased. Rate limitations did not appear to relate to low oxygen levels or to the availability of organic nutrients. Some oxidation of l-[U-C]glutamic acid occurred even at extreme salinities, whereas oxidation of [1-C]hexadecane was too low to be detected. Gas chromatographic examination of hexane-soluble components of tar samples from natural seeps at Rozel Point in Great Salt Lake demonstrated no evidence of biological oxidation of isoprenoid alkanes subject to degradation in normal environments. Some hexane-soluble components of the same tar were altered by incubation in a low-salinity enrichment culture inoculated with garden soil. Attempts to enrich for microorganisms in saline waters able to use mineral oil as a sole source of carbon and energy were successful below, but not above, about 20% salinity. This study strongly suggests a general reduction of metabolic rate at extreme salinities and raises doubt about the biodegradation of hydrocarbons in hypersaline environments. PMID:16345276

  12. Polycyclic hydrocarbons - occurrence and determination

    International Nuclear Information System (INIS)

    Polycyclic aromatic hydrocarbons (PAHs) are a special group of atmospheric contaminants included in the persistent toxic substances (PTS) and also in the volatile organic compounds (VOC) groups. PAHs are present in the atmosphere and their origin can be due to anthropogenic activities. The main source of emission of PAH is the combustion of fossil fuels. Their specific characteristics, high volatility, mutagenic and carcinogenic power, easily transportable for long distances with the wind, make them important contaminants despite of the fact that they are present at very low concentrations. The report provides a review of main analytical methods applied in the determination of PAH in air. Special attention was devoted to heterocyclic PAH which contain one or more heteroatom (sulphur, oxygen, nitrogen) in the multiple-fused ring. The presence of heterocyclic PAH requires very complex, laborious and long lasting sample separation methods before analysis. In some cases, application of different temperature programs in gas chromatography allows to determine PAH and heterocyclic PAH in gaseous samples without sample pretreatment. Gas chromatography methods for the determination of PAH and heterocyclic PAH in the gas from combustion of light heating oil has been optimized. (author)

  13. Secondary pool boiling effects

    Science.gov (United States)

    Kruse, C.; Tsubaki, A.; Zuhlke, C.; Anderson, T.; Alexander, D.; Gogos, G.; Ndao, S.

    2016-02-01

    A pool boiling phenomenon referred to as secondary boiling effects is discussed. Based on the experimental trends, a mechanism is proposed that identifies the parameters that lead to this phenomenon. Secondary boiling effects refer to a distinct decrease in the wall superheat temperature near the critical heat flux due to a significant increase in the heat transfer coefficient. Recent pool boiling heat transfer experiments using femtosecond laser processed Inconel, stainless steel, and copper multiscale surfaces consistently displayed secondary boiling effects, which were found to be a result of both temperature drop along the microstructures and nucleation characteristic length scales. The temperature drop is a function of microstructure height and thermal conductivity. An increased microstructure height and a decreased thermal conductivity result in a significant temperature drop along the microstructures. This temperature drop becomes more pronounced at higher heat fluxes and along with the right nucleation characteristic length scales results in a change of the boiling dynamics. Nucleation spreads from the bottom of the microstructure valleys to the top of the microstructures, resulting in a decreased surface superheat with an increasing heat flux. This decrease in the wall superheat at higher heat fluxes is reflected by a "hook back" of the traditional boiling curve and is thus referred to as secondary boiling effects. In addition, a boiling hysteresis during increasing and decreasing heat flux develops due to the secondary boiling effects. This hysteresis further validates the existence of secondary boiling effects.

  14. Mediterranean Migrations: Regionalisms Versus Globalisation

    Directory of Open Access Journals (Sweden)

    Martin Baldwin-Eduards

    2004-06-01

    Full Text Available This paper challenges the claim of globalisation as a cause ofimmigration into Southern Europe and, on an empirical basis, identifies regionalisation as being the primary issue, along with networked migratory patterns. However, the changing patterns of immigration do present challenges to both state and society. It is argued here that recent policy responses in Portugal, Italy and Spain have been inconsistent and irrational – reflecting more the ‘securitisation’ of migration than European reality. Earlier policy innovations are identified, by country and date: most of these have now been abandoned. It is suggested that all of Southern Europe has converged onto a statist, restrictionist model of immigration control that was formerly held only by Greece. The principal characteristics of this model are outlined, along with a migration flowchart and indicative data for migrant flows and sub-flows in Italy and Spain. In the final section, I try to show that the needs of the economy cannot be predicted, immigration cannot becontrolled in the manner currently being enforced across Southern Europe, and attempts to do so will damage rather than improve economic productivity and growth. The concept of an accomodating immigration policy is advanced, whereby the state tries to manage the needs of both employers and potential migrants. Six guidelines for policy development are suggested – most of which have alreadybeen successfully carried out in the European Union. These are the following: migration in order to find a job; circular cross-border migration; EU level negotiation of readmission agreements; the need for a variety of migration-for-employment schemes; legal residence should not depend upon continuity of employment; and discreet legalisation will still be needed in Southern Europe.

  15. Lymphocyte migration across major histocompatibility barriers in splenectomized rats.

    Science.gov (United States)

    Nieuwenhuis, P; de Vries-Bos, L; Opstelten, D; Deenen, G J; Stet, R J; Rozing, J

    1983-01-01

    Localisation and migration patterns of iv injected radio-labelled thoracic duct (TD) lymphocytes were studied in particular with regard to passage through lymph nodes and re-entry into thoracic duct lymph. To avoid unwanted splenic sequestration of migrating lymphocytes presenting alloantigens to the recipient, only splenectomized recipients were used. Donor cells and recipients differed at the MHC (RT-1) locus, either in fully allogeneic (AO -- greater than BN and v.v.) or semi-allogeneic (AO -- greater than AO X BN and v.v.) combinations. In two of these combinations (BN -- greater than AO and AO X BN -- greater than AO) deficient output in TD lymph correlated with deficient localisation in lymph nodes and high amounts of radioactivity in the liver. In the other allogeneic combination (AO -- greater than BN), however, high TD output (i.e. when compared with the syngeneic combination BN -- greater than BN) correlated with good localisation in lymph nodes and low (control) levels of radioactivity in the liver. It was postulated that lymphocyte migration from blood to lymph under these circumstances can only be studied as an artifact secondary to whether or not migrating cells are removed from the circulation before they can reach and cross HEV's. These Allogeneic (or Altered) Lymphocytes Removing Tissues (by definition: Extranodular) may (conceptually) be comprised within one system: ALERT. It is our working hypothesis that the study of lymphocyte migration across (major) histocompatibility barriers is seriously impaired by the functioning of ALERT. It might be worthwhile to try and create conditions in which interference by this system is prevented, e.g. by using tolerant animals or bone-marrow chimeras. PMID:6350159

  16. Biodegradation of petroleum hydrocarbons at low temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Whyte, L. G.; Greer, C W. [National Research Council of Canada, NRC--Biotechnology Research Institute, Montreal, PQ (Canada)

    1999-07-01

    Bioremediation of contaminated Arctic sites has been proposed as the logistically and economically most favorable solution despite the known technical difficulties. The difficulties involve the inhibition of pollutants removal by biodegradation below freezing temperatures and the relative slowness of the process to remove enough hydrocarbon pollutants during the above-freezing summer months. Despite these formidable drawbacks, biodegradation of hydrocarbon contaminants is possible even in below-zero temperatures, especially if indigenous psychrophilic and psychrotropic micro-organism are used. This paper reports results of a study involving several hydrocarbon-degrading psychrotropic bacteria and suggests bioaugmentation with specific cold-adapted organisms and/or biostimulation with commercial fertilizers for enhancing degradation of specific contaminants in soils from northern Canada. An evaluation of the biodegradation potential of hydrocarbon contaminated soils in the high Arctic suggested that the contaminated soils contained sufficient numbers of cold-adapted hydrocarbon-degrading bacteria and that the addition of fertilizer was sufficient to enhance the level of hydrocarbon degradation at low ambient summer temperatures. 9 refs., 2 tabs., 3 figs.

  17. Monitoring of microbial hydrocarbon remediation in the soil

    OpenAIRE

    Chikere, Chioma Blaise; Gideon Chijioke OKPOKWASILI; Chikere, Blaise Ositadinma

    2011-01-01

    Bioremediation of hydrocarbon pollutants is advantageous owing to the cost-effectiveness of the technology and the ubiquity of hydrocarbon-degrading microorganisms in the soil. Soil microbial diversity is affected by hydrocarbon perturbation, thus selective enrichment of hydrocarbon utilizers occurs. Hydrocarbons interact with the soil matrix and soil microorganisms determining the fate of the contaminants relative to their chemical nature and microbial degradative capabilities, respectively....

  18. Laser spectroscopy of hydrocarbon radicals

    Energy Technology Data Exchange (ETDEWEB)

    Chen, P. [Harvard Univ., Cambridge, MA (United States)

    1993-12-01

    The author reports the application of supersonic jet flash pyrolysis to the specific preparation of a range of organic radicals, biradicals, and carbenes in a skimmed molecular beam. Each species was produced cleanly and specifically, with little or no secondary reactions by the thermal dissociation of appropriately designed and synthesized organic precursors. Photoelectron spectra of the three isomeric C{sub 3}H{sub 2} carbenes, ortho-benzyne, and the {alpha},3-dehydrotoluene biradical, were used to establish adiabatic ionization potentials for use in thermochemical determinations.

  19. Migration Theories and Mental Health in Toni Morrison's Jazz

    OpenAIRE

    Leila Tafreshi Motalgh; Wan Roselezam Wan Yahya

    2015-01-01

    This article aims to elaborate the relationship between migration and mental health problems that are evident in migrant women in Toni Morrison's Jazz (1992). To this end, pre-migration, migration and post-migration stress factors are identified in the novel based on Danish Bhugra's theory of migration. It seems that pre-migration stress factors and traumas are associated with the push theory of migration, while post-migration stresses are associated with the pull theory of migration. Despite...

  20. Effects of thermal maturation on steroid hydrocarbons as determined by hydrous pyrolysis of Phosphoria Retort Shale

    Science.gov (United States)

    Lewan, M. D.; Bjorøy, M.; Dolcater, D. L.

    1986-09-01

    Hydrous pyrolysis experiments on the Phosphoria Retort Shale generate bitumen extracts and expelled oils that have steroid hydrocarbons with m/z 217-, 231-, and 253-mass Chromatographic distributions that are similar to those of bitumens and crude oils in the natural system. These experiments agree with the natural observations that diasteroid hydrocarbons increase relative to their regular counterparts with increasing thermal stress, while their C 27 through C 29 proportionality shows a slight enrichment in C 27. Relative concentrations of 20S to 20R configurations of 24-ethyl-14?,17?-cholestane show the expected increase with increasing thermal stress into the early part of the primary oil generation stage, but thereafter decrease with increasing thermal stress. If this reversal is found in high maturity sections of the natural system, the utility of this transformation as a maturity index will be limited. Triaromatic- to monoaromatic-steroid hydrocarbon concentrations increase with increasing thermal stress as observed in the natural system. Preferred migration of monoaromatic steroid hydrocarbons from bitumen extracts to expelled oils places considerable doubt on currently employed kinetic models for this aromatization reaction. As in the natural system, the experiments show relative concentrations of low-molecular weight- to high-molecular weight-triaromatic steroid hydrocarbons to increase with increasing thermal stress. Assuming a first-order reaction rate, the apparent activation energy and pre-exponential factor for this apparent side-chain cleavage reaction are 175.59 kJ mol -1 and 2.82 × 10 13hr-1, respectively. These kinetic parameters are geologically reasonable and are similar to those for the overall generation of expelled oil.

  1. International parental migration and the psychological well-being of children in Ghana, Nigeria, and Angola.

    Science.gov (United States)

    Mazzucato, Valentina; Cebotari, Victor; Veale, Angela; White, Allen; Grassi, Marzia; Vivet, Jeanne

    2015-05-01

    When parents migrate, leaving their children in the origin country, transnational families are formed. Transnational family studies on children who are "left behind" indicate that children suffer psychologically from parental migration. Many of the factors identified as affecting children's responses to parental migration however are not considered in child psychology and family sociology studies. This study aims to bridge these areas of knowledge by quantitatively investigating the association between transnational families and children's psychological well-being. It analyzes a survey conducted in three African countries in 2010-11 (Ghana N = 2760; Angola N = 2243; Nigeria N = 2168) amongst pupils of secondary schools. The study compares children in transnational families to those living with their parents in their country of origin. Children's psychological well-being is measured through the Strengths and Difficulties Questionnaire. Multiple regression analyses reveal that children in transnational families fare worse than their counterparts living with both parents but not in Ghana where living conditions mediate this relationship. This paper also looks at four characteristics of transnational families and finds that specific characteristics of transnational families and country contexts matter: (1) changing caregivers is associated with poorer well-being in all countries; (2) which parent migrates does not make a difference in Ghana, when mothers migrate and fathers are caregivers results in poorer well-being in Nigeria, and both mother's and father's migration result in worse outcomes in Angola; (3) the kin relationship of the caregiver is not associated with poorer well-being in Ghana and Nigeria but is in Angola; (4) children with parents who migrate internationally do not show different results than children whose parents migrate nationally in Ghana and Nigeria but in Angola international parental migration is associated with poorer psychological well-being. The study shows that broader characteristics in the population rather than parental migration per se are associated with decreased levels of well-being. PMID:25464874

  2. Improved carbon migration modelling with the ERO code

    Energy Technology Data Exchange (ETDEWEB)

    Van Hoey, Olivier, E-mail: ovhoey@sckcen.be [Department of Applied Physics, Ghent University, Rozier 44, 9000 Ghent (Belgium); Institute for Nuclear Materials Science, SCK-CEN, Boeretang 200, 2400 Mol (Belgium); Kirschner, Andreas; Björkas, Carolina; Borodin, Dmitry [Institute for Energy and Climate Research – Plasma Physics, Forschungszentrum Jülich, Wilhelm-Johnen-Strasse, 52425 Jülich (Germany); Matveev, Dmitry [Department of Applied Physics, Ghent University, Rozier 44, 9000 Ghent (Belgium); Institute for Energy and Climate Research – Plasma Physics, Forschungszentrum Jülich, Wilhelm-Johnen-Strasse, 52425 Jülich (Germany); Uytdenhouwen, Inge [Institute for Nuclear Materials Science, SCK-CEN, Boeretang 200, 2400 Mol (Belgium); Van Oost, Guido [Department of Applied Physics, Ghent University, Rozier 44, 9000 Ghent (Belgium)

    2013-07-15

    Material migration is a crucial issue in thermonuclear fusion devices. To study carbon migration, {sup 13}CH{sub 4} has been injected through a polished graphite roof-like test limiter in the TEXTOR scrape-off layer. The interpretation of the experimental {sup 13}C deposition patterns on the roof limiter surface has been done with the ERO impurity transport code. To reproduce the very low experimental {sup 13}C deposition efficiencies with ERO, an enhanced re-erosion mechanism for re-deposited carbon had to be assumed in previous studies. However, erosion by hydrogenic species produced during dissociation of injected {sup 13}CH{sub 4} was not taken into account by ERO in these studies. This additional erosion could maybe explain the very low experimental {sup 13}C deposition efficiencies. Therefore, it is now taken into account in ERO. Also more realistic physical sputtering yields and hydrocarbon reflection probabilities have been implemented in ERO. The simulations with these improvements included clearly confirm the need for enhanced re-erosion of re-deposited carbon.

  3. Depth migration and de-migration for 3-D migration velocity analysis; Migration profondeur et demigration pour l'analyse de vitesse de migration 3D

    Energy Technology Data Exchange (ETDEWEB)

    Assouline, F.

    2001-07-01

    3-D seismic imaging of complex geologic structures requires the use of pre-stack imaging techniques, the post-stack ones being unsuitable in that case. Indeed, pre-stack depth migration is a technique which allows to image accurately complex structures provided that we have at our disposal a subsurface velocity model accurate enough. The determination of this velocity model is thus a key element for seismic imaging, and to this end, migration velocity analysis methods have met considerable interest. The SMART method is a specific migration velocity analysis method: the singularity of this method is that it does not rely on any restrictive assumptions on the complexity of the velocity model to determine. The SMART method uses a detour through the pre-stack depth migrated domain for extracting multi-offset kinematic information hardly accessible in the time domain. Once achieved the interpretation of the pre-stack depth migrated seismic data, a kinematic de-migration technique of the interpreted events enables to obtain a consistent kinematic database (i.e. reflection travel-times). Then, the inversion of these travel-times, by means of reflection tomography, allows the determination of an accurate velocity model. To be able to really image geologic structures for which the 3-D feature is predominant, we have studied the implementation of migration velocity analysis in 3-D in the context of the SMART method, and more generally, we have developed techniques allowing to overcome the intrinsic difficulties in the 3-D aspects of seismic imaging. Indeed, although formally the SMART method can be directly applied to the case of 3-D complex structures, the feasibility of its implementation requires to choose well the imaging domain. Once this choice done, it is also necessary to conceive a method allowing, via the associated de-migration, to obtain the reflection travel-times. We first consider the offset domain which constitutes, still today, the strategy most usually used for the application of migration velocity analysis. We are interested in particular in an important problem: the influence of irregularities in seismic acquisition on the quality of the depth migrated images. Indeed, 3-D seismic acquisitions show irregularities which are characterized by offset variations as well as a non uniform spatial sampling of the data. To overcome the first kind of irregularities, we propose to introduce the concept of migration by offset class in which are migrated all seismic traces that belong to a given offset class, and we show that such a migration relies on a sound theoretical basis whenever the offset varies smoothly with the midpoint coordinate. These theoretical considerations are validated experimentally: offset classes constructed so that the offset varies slowly with the midpoint coordinate allow to obtain the required imaging quality for migration velocity analysis. The influence, on the quality of the migrated images, of a non uniform spatial sampling of the data is, as for it, much more important than the one linked to offset variations: the computation of the superposition of migrated images associated with each midpoint requires the use of a genuine numerical integration formula. We study quadrature formulas based on polynomial interpolation procedures of the function to be integrated. We recommend to use the Hermite interpolation based numerical integration formula if we are primarily interested in amplitude variations in the case of gently dipping layers, and the Lagrange interpolation based numerical integration formula for the imaging of structures involving some complexity. Moreover, the implementation of these schemes of interpolation consists of a preprocessing of the data and does not really increase the CPU time required for running the migration itself. Of course, these approaches require that the distribution of midpoints is dense enough so as to take correctly into account the variations of the function to be integrated. However, the imaging in the offset domain turns out to be with difficulty viable, because quite expensive in CPU time, in the framework of migration velocity analysis in 3-D for the imaging of complex structures: in this case, the availability of a full volume imaging technique is essential. Thus, we are interested in an original full volume pre-stack depth migration technique which is based on cylindrical wave data and is quite affordable in terms of computation cost. This migration is designed specifically for standard marine acquisitions. To be able to use this imaging technique for making use of the 3-D SMART method, we have implemented the kinematic de-migration of migrated cylindrical wave data. We theoretically justify the proposed de-migration technique and validate it both on a synthetic data set and on a real data set from the North Sea. (author)

  4. Medical migration within Europe: opportunities and challenges.

    Science.gov (United States)

    Ling, Kate; Belcher, Paul

    2014-12-01

    The free movement of European citizens to live and work within the European Union (EU) is one of the fundamental pillars of the European single market. Recent EU legislation on the recognition of professional qualifications (to take effect January 2016) updates the framework within which doctors and others can migrate freely between EU member states to practise their profession. UK organisations lobbied extensively to change aspects of the original proposals, in particular those that threatened to 'water down' public protection in the interest of free movement. The legislation finally adopted significantly increases safeguards for patients and the public. The revised law covers the rules to be applied by regulators on (for example) assuring language competence, warning 'blacklists' of practitioners subject to sanctions, 'fast track' registration based on mutual recognition of professional qualifications, agreed minimum education and training requirements for mutual recognition, and encouragement of continuing professional development. Drafting of detailed secondary legislation is ongoing and poses opportunities and challenges for patient safety, quality of care and transparency. PMID:25468849

  5. Petroleum Migration, Filling and Biological Degradation in Mesozoic Reservoirs in the Northern North Sea

    Energy Technology Data Exchange (ETDEWEB)

    Horstad, I.

    1995-12-31

    This thesis comprises five papers the first of which discusses the distribution of petroleum within the Gullfaks Field and applies conventional geochemical techniques to characterize the petroleum distribution within a single field. The paper also shows how understanding geochemical heterogeneities in the petroleum fluids helped to build a better geological model of the development of the Gullfaks Field. Based on this work an improved filling model was proposed for the Gullfaks Field. The second paper discusses the biological degradation of the hydrocarbons within the Gullfaks Field, and shows how several samples from neighbouring fields were analyzed to confirm the filling model of the field. It also demonstrates how the quantification of biological degradation of hydrocarbons in the reservoir places constraints on acceptable models of the geological development of the Tampen Spur Area. The third paper discusses the source vs. sink problems of petroleum migration in the North Sea. The fourth paper is a regional study of the petroleum migration within the Tampen Spur area and proposes a regional migration model. The fifth paper is a detailed reservoir geochemical study of the giant Troll Field on the Horda Platform and proposes a revised filling model for the field. 224 refs., 86 figs., 5 tabs.

  6. Partial migration in fishes: causes and consequences

    DEFF Research Database (Denmark)

    Chapman, B.B.; Hulthén, K.

    2012-01-01

    Partial migration, where only some individuals from a population migrate, has been widely reported in a diverse range of animals. In this paper, what is known about the causes and consequences of partial migration in fishes is reviewed. Firstly, the ultimate and proximate drivers of partial migration are reflected upon: what ecological factors can shape the evolution of migratory dimorphism? How is partial migration maintained over evolutionary timescales? What proximate mechanisms determine whether an individual is migratory or remains resident? Following this, the consequences of partial migration are considered, in an ecological and evolutionary context, and also in an applied sense. Here it is argued that understanding the concept of partial migration is crucial for fisheries and ecosystem managers, and can provide information for conservation strategies. The review concludes with a reflection on the future opportunities in this field, and the avenues of research that are likely to be fruitful to shed light on the enduring puzzle of partial migration in fishes

  7. The circular migration of smallholders in Kenya.

    Science.gov (United States)

    Bigsten, A

    1996-01-01

    Circular migration is a central phenomenon in the lives of smallholders in East Africa. Many migration decisions are not individual decisions, but rather household decisions in which the household allocates its labor force among activities to maximize household utility. A probit model which incorporates circular migration and takes into account contacts, information, and indivisibilities is used to analyze migration among 763 farm households in the Central and Nyanza provinces of Kenya. Study data are from a 1982 survey. The pull of high urban wages appears to be a far more important determinant of migration decision outcomes than the push of land scarcity, while a strong local nonagricultural economy does not seem to restrict migration. Networks of personal contacts were found to be highly significant determinants of migration. These findings suggest that rural development will probably not reduce the flow of migration. PMID:12320851

  8. Nanoparticles migration in fractured rocks and affects on contaminant migration

    Science.gov (United States)

    Missana, Tiziana; Garcia-Gutierrez, Miguel; Alonso, Ursula

    2014-05-01

    In previous studies, the transport behavior of artificial (gold and latex) and natural (smectite clay) colloids, within a planar fracture in crystalline rock, was analyzed. In order to better understand the effects of colloid size, shape and surface charge on nanoparticle migration and especially on filtration processes on natural rock surfaces, different clay colloids and oxide nanoparticles were selected and their transport studied as a function of the residence time. In all the cases, (a fraction of) the nanoparticles travelled in the fracture as fast as or faster than water (with a retardation factor, Rf ? 1) and the observed Rf, was related to the Taylor dispersion coefficient, accounting for colloid size, water velocity and fracture width. However, under most of the cases, in contrast to the behavior of a conservative tracer, colloids recovery was much lower than 100 %. Differences in recovery between different nanoparticles, under similar residence times, were analyzed. In order to evaluate the possible consequences, on contaminant migration, of the presence of nanoparticles in the system, transport tests were carried out with both colloids and sorbing radionuclides. The overall capacity for colloids of enhancing radionuclide migration in crystalline rock fractures is discussed. Acknowledgments: The research leading to these results received funding from EU FP7/2007-2011 grant agreement Nº 295487 (BELBAR, Bentonite Erosion: effects on the Long term performance of the engineered Barrier and Radionuclide Transport) and by the Spanish Government under the project NANOBAG (CTM2011-2797).

  9. Is deportation a form of forced migration?

    OpenAIRE

    Gibney, MJ

    2013-01-01

    In this article I explore why, despite the fact that it seems to represent the epitome of forced migration, deportation (the quotidian practice of lawful expulsion) is generally ignored by forced migration scholars. My key claim is that deportation is implicitly deemed a legitimate form of forced migration. Forced migration is not simply a descriptive term; it is also typically an evaluative one. Deportation is treated differently because it does not violate the key principles of a liberal-st...

  10. Risk-taking in unauthorised migration

    OpenAIRE

    Hernández Carretero, María

    2008-01-01

    This thesis addresses the dynamics of high-risk unauthorised migration. First, it explores how new routes develop in relation to policies that seek to curtail unauthorised migration. Second, it analyses how aspiring migrants justify taking certain risks to migrate by negotiating risk information in relation to their life circumstances and considering the symbolic value of specific forms of migration. Finally and, in relation to the previous, the thesis discusses whether policies that seek to ...

  11. Globalization and formal sector migration in Brazil

    OpenAIRE

    Aguayo-Tellez, Ernesto; Muendler, Marc-Andreas; Poole, Jennifer Pamela

    2008-01-01

    We use novel linked employer–employee data to study the relationship between globalization and formal sector interstate migration for Brazil. We estimate the worker’s multichoice migration problem and document that previously unobserved employer covariates are significant predictors associated with migration flows. Our results provide support for the idea that globalization acts on internal migration through the growth of employment opportunities at locations with a high concentration of fore...

  12. Capitalist development and internal migration in Nigeria.

    Science.gov (United States)

    Akor, R I; Mou, D

    1986-12-01

    The authors analyze internal migration trends in Nigeria by examining individual household strategies and how they have adapted to structural changes brought about by colonial rule and capitalist development. The first section of this article describes the structural changes that started the process of labor migration. The second section deals with post-independence industrialization and the consequent rural-urban migration. The final section analyzes the consequences of these migration patterns for urban growth and rural productivity. PMID:12280787

  13. Migration and rural opportunities in Nigeria.

    Science.gov (United States)

    Adepoju, A

    1984-01-01

    This study is concerned with migration to rural areas in Nigeria. The author examines the rural economic structures, social systems, and demographic features affecting such migration. These features are compared for migrants and nonmigrants in the cash cropping and subsistence cropping areas of southwestern Nigeria. The results suggest that rural migration in southwestern Nigeria is mainly urban-rural migration of a colonizing type. Data for the study are from a survey of 1,782 households in 12 villages. PMID:12339440

  14. Theoretical aspects of studying the migration processes

    Directory of Open Access Journals (Sweden)

    Dilfuza Rasulova

    2010-02-01

    Full Text Available In conditions of continuous growth of population in Uzbekistan the issue of managing the labor migration processes is becoming more important. Effective coordination of migration processes requires comprehensive study of theory and methodology of labour migration, particularly considering cases of transition countries. The paper considers some theoretic concepts that seem important for understanding the mechanism of migration princesses, suggests practical recommendations for the associated decision-making.

  15. Migration and Child Growth in Rural Guatemala

    OpenAIRE

    Carletto, Calogero; Covarrubias, Katia; Maluccio, John A.

    2011-01-01

    This paper examines the relationship between migration and child growth in the rural highlands of Guatemala, a region with substantial international migration outflows, significant remittance inflows, and some of the highest rates of child undernutrition in the world. Using cross-sectional survey data, a double-difference approach based on child growth patterns that controls for the selectivity of migration is used to assess the impact of migration to the US on Height-for-Age Z (HAZ) scores a...

  16. Socio-Economic Determinants of International Migration

    OpenAIRE

    Yaroslav PRYTULA; Nataliia POHORILA

    2012-01-01

    Since economic factors cannot fully explain the determinants of bilateral migration, this study explores the social and cultural determinants that influence an individual’s decision to migrate. Values, norms and interests in a given culture, may determine whether an individual’s intention to move translates into actual migration. Work values inherent in different cultures could explain why people move or do not move under the condition of perceived economic advantages of migration. A gravity ...

  17. The Dynamics of Health and Return Migration

    OpenAIRE

    Anita A Davies; Rosilyne M Borland; Carolyn Blake; West, Haley E.

    2011-01-01

    Return migration and health has received little attention in policy and research. This article will focus on the risk factors and social determinants of health during all phases of migration that can impact the health of returnees. It will highlight the diversity of returning migrants and illustrate through examples how return migration can influence the health of individuals and populations. The paper will conclude with policy recommendations for healthy return migration. URL:[http://www.plo...

  18. The Influence of Others on Migration Plans

    OpenAIRE

    Epstein, Gil S.; Gang, Ira. N

    2004-01-01

    The willingness to migrate and locational choice may be influenced by others’ choices or plans, particularly if the ‘other people’, such as family and friends, are migrants, former migrants, or potential migrants themselves. We examine the roles ‘other people’ play in influencing an individual’s potential migration decision. In analysing the influence of others on migration decisions, we rely on the concepts of migration networks and herd effects.

  19. Migration and mental health: An interface

    OpenAIRE

    Virupaksha, H. G.; Kumar, Ashok; Nirmala, Bergai Parthsarathy

    2014-01-01

    Migration is a universal phenomenon, which existed with the subsistence of the human beings on earth. People migrate from one place to another for several reasons, but the goal or main reason behind changing the residence would be improving their living conditions or to escape from debts and poverty. Migration is also a social phenomenon which influences human life and the environment around. Hence, migration has a great impact on any geographical area and it is known as one of the three basi...

  20. Juridical structures: refugees and migration.

    Science.gov (United States)

    Veiter, T

    1988-01-01

    The juridical problems in regard to the concepts of refugee, expulsion, and migration are complicated. If one speaks about migration in Europe, one must 1st distinguish between Eastern and Western Europe. In the communist states of Eastern Europe the refugee problem does not exist officially, with the only existing refugee problem in Yugoslavia, which has signed and ratified the Geneva Refugee Convention of 1951. In the other East European states the right to asylum exists, but refugees are granted asylum only if they are persecuted in their country of origin for their communist ideas and activities. In speaking of migration, one must distinguish between migration, forced migration, mass migration, emigration, immigration, the shift of populations, and refugees. In the communist countries of Eastern Europe the right to emigration is not respected, although certain exceptions, as in Poland or Yugoslavia do exist. Generally, in the communist states emigration is not allowed and illegal emigration is punished as "Flight from the Republic." With a few exceptions, political and other persecutions are no longer so typical within Europe. In the last decades, the refugee problem has changed to other continents: Afghanistan/Pakistan, Iran, Sri Lanka, East Timor, Lebanon, Palestine, Sudan, Tchad, Ethiopia, Eritrea, and Angola. The refugee problem in Europe consists mainly in the large afflux of refugees coming from places with other cultural (and religious) attributes. The Islamic immigrants declare themselves regularly as political refugees and hope to be acknowledged as such by the receiving state. The fear of the governments and populations of the receiving countries is that it would not be possible to assimilate such aliens who do not belong to the Christian culture of Europe. Formerly, refugees came mostly from the Christian countries of Eastern Europe with the same race identity and the same religion. For years now, more and more foreign workers are a kind of migrant within the European Economic Community, and now total about 14 million. Within international public law, there exists the principle of non-refoulement which protects a refugee (and also an asylum-seeker not recognized as a refugee) against expulsion or return, in any manner whatsoever, to a territory where his life or freedom would be threatened on account of his race, nationality, religion, or membership in a particular social group or political opinion. PMID:12281755