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1

Subsurface migration of petroleum hydrocarbons: A case study of immiscible migration and chromatographic separation  

International Nuclear Information System (INIS)

[en] The subsurface distribution of a leaked crude oil illustrates the combined influence of both the chemical and physical properties of soil and free product on the migration of petroleum hydrocarbons. Immiscible phase behavior was observed, as well as chromatographic-like separation of the lighter constituents of the crude oil from the heavier constituents. After downward migration through approximately 50 ft of unsaturated, heterogeneous alluvial sediments, the crude oil formed a horizontal plume on top of a perched, saturated zone. Immiscible phase trapping is evident from the occurrence of very high concentration of hydrocarbons in both the vertical and horizontal plumes. Samples taken from the vertical zone of contamination indicate a transition from heavier hydrocarbons near the surface to lighter hydrocarbons at depth. This phenomenon is attributed to chromatographic-like separation of the heavier hydrocarbons by the soil, possibly due to preferential solubility of the lighter hydrocarbons in percolating ran water

1991-01-01

2

Application of paleomagnetic techniques for dating hydrocarbon migration events  

Energy Technology Data Exchange (ETDEWEB)

Establishing a relationship between hydrocarbon migration and the precipitation of authigenic magnetite is important for the development of a method to date hydrocarbon migration using paleomagnetic techniques. Important evidence for the relationship comes from a study of light and dark-banded calcite speleothems that occur in Ordovician limestones in southern Oklahoma. The speleothems are Permian in age, based on interbedded fossils. The dark bands contain primary fluid inclusions filled with hydrocarbons that are not extensively biograded. They also possess over an order of magnitude stronger magnetization than light bands. Paleomagnetic and rock magnetic data indicate that the magnetization in the dark bands was acquired during the Early Permian and resides in magnetite. Spheres, interpreted to be authigenic magnetite, are also found in magnetic extracts from the dark calcite. The results from the light and dark bands suggest that chemical conditions created by the hydrocarbons caused precipitation of authigenic magnetite and acquisition of the associated chemical remanent magnetization.

Elmore, R.D.

1988-01-01

3

The pulsed migration of hydrocarbons across inactive faults  

Directory of Open Access Journals (Sweden)

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.

S. D. Harris; L. Elliott; R. J. Knipe

1999-01-01

4

Genesis and migration of petroleum in selected Dogger beta deposits of the Gifhorn trough: Interdependences between hydrocarbon genesis and sandstone diagenesis. Herkunft und Migration des Erdoels in ausgewaehlten Dogger beta Lagerstaetten des Gifhorner Troges: Wechselwirkungen zwischen Kohlenwasserstoffgenese und Sandsteindiagenese  

Energy Technology Data Exchange (ETDEWEB)

Bedrock and deposit rock samples (lias epsilon to Dogger beta) from selected sites of the Gifhorn trough (Ruehme, Vorhop Meerdorf) were analyzed by detailed organic-geochemical, mineralogical and sediment-petrographic methods in order to find out about the hydrocarbon genesis, the interdependence between hydrocarbon genesis and sandstone diagenesis, and various geochemical effects during primary and secondary migration. Further, an attempt was made to date hydrocarbon genesis, migration, and sandstone diagenesis within the history of the Gifhorn trough.

Schwarzkopf, T.

1987-11-13

5

Fractures, faults, and hydrocarbon entrapment, migration and flow  

Energy Technology Data Exchange (ETDEWEB)

This paper presents an overview of the role of structural heterogeneities in hydrocarbon entrapment, migration and flow. Three common structural heterogeneity types are considered: (1) dilatant fractures (joints, veins, and dikes); (2) contraction/compaction structures (solution seams and compaction bands); and (3) shear fractures (faults). Each class of structures has a different geometry, pattern, and fluid flow property, which are described by using analog outcrop studies, conceptual models, and, in some cases, actual subsurface data. Permeability of these structures may, on average, be a few orders of magnitude higher or lower than those of the corresponding matrix rocks. Based on these differences and the widespread occurrence of fractures and faults in rocks, it is concluded that structural heterogeneities should be essential elements of hydrocarbon migration and flow as well as entrapment and that they should be included in large-scale basin models and reservoir-scale simulation models. This proposition is supported by a number of case studies of various reservoirs presented in this paper. (author)

Aydin, A. [Stanford Univ., Stanford, CA (United States). Dept. of Geological and Environmental Sciences

2000-08-01

6

Method and apparatus for secondary and tertiary recovery of hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

This patent describes an apparatus for secondary and tertiary recovery of hydrocarbons from oil fields comprising: a. a bipropellant generator capable of producing exhaust gases at supercritical pressures and temperatures; b. transport means for carrying the exhaust gases into a well bore, at least a portion of the well bore extending into a hydrocarbon bearing formation from which hydrocarbons are to be recovered; c. means for introducing water into the transport means; and d. a water cooling jacket extending into at least the upper portion of the well bore, the center of the cooling jacket receiving the exhaust gases from the transport means, means being provided for the introduction of chemical additives through a portion of the cooling jacket. A process is described for secondary and tertiary recovery of hydrocarbons from geological formations comprising: a. providing a well bore extending at least into the strata of the geologic formation containing the hydrocarbons to be recovered; b. providing at least the upper portion of the well bore with a cooling jacket, the cooling jacket being provided with a central, open portion; c. generating gases at supercritical temperatures and pressures; d. introducing water into the supercritical gases to form steam; e. forcing the mixture of supercritical combustion gases and steam through the central open portion of the cooling jacket and the well bore into the hydrocarbon strata; and f. adding chemical additives to the mixture of combustion gases and steam below the cooling jacket.

Rivas, N.; Beichel, R.

1987-07-07

7

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

Science.gov (United States)

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

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

2010-09-17

8

Magnetic enhancement caused by hydrocarbon migration in the Mawangmiao Oil Field, Jianghan Basin, China  

Energy Technology Data Exchange (ETDEWEB)

Magnetic parameters (volume-specific susceptibility k, and hysteresis parameters and ratios) of 47 samples, collected from an oil-producing well (M{sub 36}) and a dry well (M{sub 46}) from the oil-bearing II-You Formation of Paleogene Xingouzui Group in the Mawangmiao Oil Field in China, were measured to address the secondary alteration of iron-bearing minerals associated with hydrocarbon migration. Our results indicated that both k and magnetization (saturation magnetization J{sub s} and saturation isothermal remanent magnetization J{sub rs}) of oil-bearing formation have been dramatically enhanced. Further grain size estimation reveals that the background samples (samples both in M{sub 46} and outside the oil-bearing formation in M{sub 36}) contain coarser-grained magnetic particles (circa 30{mu}m) of detrital origin. In contrast, the alteration of hydrocarbon produces finer-grained (circa 25nm) magnetic particles. The new constraints on grain sizes and its origin of the hydrocarbon-related magnetic particles improve our understanding of the mechanism of formation of these secondary finer-grained particles, even though the precise nature of this process is still unknown. (author)

Liu, Qingsheng; Yang, Tao [Department of Geophysics, China University of Geosciences, Wuhan 430074 (China); Liu, Qingsong [National Oceanography Centre Southampton, University of Southampton, European Way, Southampton SO14 3ZH (United Kingdom); Chan, Lungsang [Department of Earth Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong (China); Xia, Xianghua; Cheng, Tongjin [Wuxi Institute of Petroleum Geology, SNOPEC, Jiangsu Wuxi 214151 (China)

2006-08-15

9

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)

2000-01-01

10

Evolution of hydrocarbon migration style in a fractured reservoir deduced from fluid inclusion data, Clair Field, west of Shetland, UK  

Energy Technology Data Exchange (ETDEWEB)

A petrographic and fluid inclusion microthermometric study was performed on sandstones from the Devonian-Carboniferous reservoir rocks of the Clair Field, west of Shetland. Fluid inclusion petrographic and microthermometric observations were collected from quartz, K-feldspar and calcite cements and veins. Vein and cement minerals host both aqueous and hydrocarbon two-phase (liquid and vapor-filled) fluid inclusions indicating that cementation occurred during oil charging. The location of hydrocarbon fluid inclusions in the paragenetic sequence of the reservoir rocks indicates that hydrocarbon migration during early-stage diagenesis occurred via intergranular pores as well as fractures, whereas towards the later stages of diagenesis, as porosities were occluded, hydrocarbon migration was predominantly fracture controlled. The microthermometric characteristics of primary and secondary aqueous fluid inclusions in association with hydrocarbon fluid inclusions indicates that cementation and veining during oil charging occurred at temperatures up to 180 C. Salinity values are variable (0-10.9 wt% NaCl eq.) indicating that fluid mixing occurred during veining and cementation. Basin modeling and vitrinite reflectance data indicate that temperatures of up to 180 C could not have been attained through burial alone. The high temperatures attained during late-stage diagenesis are interpreted to be caused by high temperature, short-lived fluids circulating within the Devonian-Carboniferous reservoir rocks in association with late Cretaceous and Paleocene magmatism. These high temperature fluid flow events were not recorded in the vitrinite reflectance data because of their short duration. (author)

Baron, Martin; Parnell, John; Mark, Darren [Department of Geology and Petroleum Geology, Meston Building, University of Aberdeen, King' s College, Aberdeen AB24 3UE (United Kingdom); Carr, Andrew [Advanced Geochemical Systems Ltd., Towles Fields, Burton on the Wolds, Leicestershire LE12 5TD (United Kingdom); British Geological Survey, Keyworth, Nottingham NG12 5GG (United Kingdom); Przyjalgowski, Milosz [Department of Physics, National University of Ireland-Galway, Galway (Ireland); Feely, Martin [Department of Geology, National University of Ireland-Galway, Galway (Ireland)

2008-02-15

11

Geochemistry of the process of hydrocarbon system migration. Geokimiya protsessa migratsii uglevodorodnykh sistem  

Energy Technology Data Exchange (ETDEWEB)

Features are examined of transformation of the composition of hydrocarbon systems in relation to thermobaric adsorption-chromatographic and diffusion factors and their differentiation during migration. A considerable place is given to questions of geochemical correlation of the oils and their change in the zones of their genesis and supergenesis. Geological-geochemical principles and methods are described for predicting the phase state of hydrocarbons in the depths, and regional examples are given of qualitative evaluation of the outlook for oil and gas content of the deposits.

Chakhmakachev, V.A.

1983-01-01

12

Regional hydrocarbon generation, migration, and accumulation pattern of Cretaceous strata, Powder River Basin  

Energy Technology Data Exchange (ETDEWEB)

A cell of abnormally high fluid pressure in the deep part of the Powder River basin is centered in an area where oil-generation-prone source rocks in the Skull Creek (oldest), Mowry, and Niobrara (youngest) formations are presently at their maximum hydrocarbon-volume generation rate. The overpressures are believed to be caused by the high conversion rate of solid kerogen in the source rocks to an increased volume of potentially expellable fluid hydrocarbons. In this area, hydrocarbons appear to be the principal mobile fluid species present in reservoirs within or proximal to the actively generating source rocks. Maximum generation pressures within the source rocks have caused vertical expulsion through a pressure-induced microfracture system and have charged the first available underlying and/or overlying sandstone carrier-reservoir bed. Hydrocarbons generated in the Skull Creek have been expelled downward into the Dakota Sandstone and upward into the Muddy Sandstone. Hydrocarbons generated in the Mowry have been expelled downward into the Muddy or upward into lower Frontier sandstones. Hydrocarbons generated in the Niobrara have been expelled downward into upper Frontier sandstones or upward into the first available overlying sandstone in the Upper Cretaceous. The first chargeable sandstone overlying the Niobrara, in ascending order, may be the (1) Shannon, (2) Sussex, (3) Parkman, (4) Teapot, or (5) Tekla, depending on the east limit of each sandstone with respect to vertical fracture migration through the Cody Shale from the underlying area of mature overpressured Niobrara source rocks.

Meissner, F.F.

1985-05-01

13

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

Energy Technology Data Exchange (ETDEWEB)

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)

Magalhaes, Marcia Santos de Almeida

1999-07-01

14

Generation and migration density of fluid and gas hydrocarbons in Jurassic and Neocomian formations of southwest Tyumen Region  

Energy Technology Data Exchange (ETDEWEB)

Utilizing known techniques, a quantitative evaluation of generation and migration of liquid and ga hydrocarbons in Lower and Middle Jurassic, Upper Jurassic, Berrias-Early Valangian, Valangian, Barremian, and Aptian oil-bearing strata is provided. Values of given parameters for the examined strata are provided. Density distribution of generation and migration of hydrocarbon in Mesozoic formations in South West Tyumen is differentiated, corresponding to the lithofacial sedimentary accumulation areas. Quantity of migrating hydrocarbon fluids is increased as one moves to shallow ocean and coastline facies from continental facies. Evaluation of the quantity of migrating liquid and gas hydrocarbons makes it possible to target primarily oil-generating formations and to regionalize areas according to their potential.

Grigor' yeva, G.F.; Rylkov, A.V.; Semenova, L.A.

1983-01-01

15

A novel molecular index for secondary oil migration distance  

Science.gov (United States)

Determining oil migration distances from source rocks to reservoirs can greatly help in the search for new petroleum accumulations. Concentrations and ratios of polar organic compounds are known to change due to preferential sorption of these compounds in migrating oils onto immobile mineral surfaces. However, these compounds cannot be directly used as proxies for oil migration distances because of the influence of source variability. Here we show that for each source facies, the ratio of the concentration of a select polar organic compound to its initial concentration at a reference point is independent of source variability and correlates solely with migration distance from source rock to reservoir. Case studies serve to demonstrate that this new index provides a valid solution for determining source-reservoir distance and could lead to many applications in fundamental and applied petroleum geoscience studies.

Zhang, Liuping; Li, Maowen; Wang, Yang; Yin, Qing-Zhu; Zhang, Wenzheng

2013-01-01

16

A novel molecular index for secondary oil migration distance.  

UK PubMed Central (United Kingdom)

Determining oil migration distances from source rocks to reservoirs can greatly help in the search for new petroleum accumulations. Concentrations and ratios of polar organic compounds are known to change due to preferential sorption of these compounds in migrating oils onto immobile mineral surfaces. However, these compounds cannot be directly used as proxies for oil migration distances because of the influence of source variability. Here we show that for each source facies, the ratio of the concentration of a select polar organic compound to its initial concentration at a reference point is independent of source variability and correlates solely with migration distance from source rock to reservoir. Case studies serve to demonstrate that this new index provides a valid solution for determining source-reservoir distance and could lead to many applications in fundamental and applied petroleum geoscience studies.

Zhang L; Li M; Wang Y; Yin QZ; Zhang W

2013-08-01

17

Evolution of salt and hydrocarbon migration: Sweet Lake area, Cameron Parish, Louisiana  

Energy Technology Data Exchange (ETDEWEB)

The interpretation of seismic, gravity, and well data in northern Cameron Parish, Louisiana suggest that lateral salt flow has influenced the area`s structural evolution, depositional patterns, and hydrocarbon migration. Sweet Lake Field has produced over 46 MMBO and 15 BCFG from Middle Miocene deltaic sands. The structural closure is a downthrown anticline on a fault controlled by the underlying salt feature. Sweet Lake Field overlies an allochthonous salt mass that was probably once part of an ancestral salt ridge extending from Hackberry to Big Lake fields. Nine wells encountering top of salt and several seismic lines define a detached salt feature underlying over twenty square miles at depths from 8500-18,000 ft. Salt withdrawal in the East Hackberry-Big Lake area influenced the depositional patterns of the Oligocene lower Hackberry channel systems. Progradation of thick Middle Oligocene Camerina (A) and Miogypsinoides sands into the area caused salt thinning and withdrawal resulting in the development and orientation of the large Marginulina-Miogypsinoides growth fault northwest of Sweet Lake. Additional evidence for the southeast trend of the salt is a well approximately two miles southeast of Sweet Lake which encountered salt at approximately 19,800 ft. High quality 2-D and 3-D seismic data will continue to enhance the regional understanding of the evolving salt structures in the onshore Gulf Coast and the local understanding of hydrocarbon migration. Additional examples of lateral salt flow will be recognized and some may prove to have subsalt hydrocarbon potential.

Spencer, J.A.; Sharpe, C.L. [Amoco Production Company, Houston, TX (United States)

1996-09-01

18

A novel approach for recognition and quantification of hydrocarbon migration effects in shale-sandstone sequences  

Energy Technology Data Exchange (ETDEWEB)

A detailed organic geochemical study of over 150 samples from two cores with a total combined length of 320 m through sequences of interbedded source rocktype shales and reservoir sandstones allowed recognition and quantitation of a number of migration effects. For the alkanes, expulsion occurs with pronounced compositional fractionation effects: shorter chain length nalkanes are expelled preferentially, and isoprenoid alkanes are expelled to a lesser degree than their straight-chain isomers. Based on material balance calculations, expulsion efficiencies were determined and found to be very high in certain instances. The composition of the hydrocarbons impregnating parts of the reservoir sandstones is in agreement with expulsion occurring with pronounced fractionation based on molecular chain length. Hence, consideration of bulk expulsion efficiencies gives an unrealistic picture. The composition of the hydrocarbon product accumulating in the reservoirs at this stage appears to be controlled primarily by physical processes rather than by the type and maturity of the organic matter in the generating source rock.

Leythaeuser, D.; Bjoroy, M.; Mackenzie, A.; Schaefer, R.G.

1984-02-01

19

An endogenous aryl hydrocarbon receptor ligand inhibits proliferation and migration of human ovarian cancer cells.  

UK PubMed Central (United Kingdom)

The aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor mediates many biological processes. Herein, we investigated if 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE, an endogenous AhR ligand) regulated proliferation and migration of human ovarian cancer cells via AhR. We found that AhR was widely present in many histotypes of ovarian cancer tissues. ITE suppressed OVCAR-3 cell proliferation and SKOV-3 cell migration in vitro, which were blocked by AhR knockdown. ITE also suppressed OVCAR-3 cell growth in mice. These data suggest that the ITE might potentially be used for therapeutic intervention for at least a subset of human ovarian cancer.

Wang K; Li Y; Jiang YZ; Dai CF; Patankar MS; Song JS; Zheng J

2013-10-01

20

An endogenous aryl hydrocarbon receptor ligand inhibits proliferation and migration of human ovarian cancer cells.  

Science.gov (United States)

The aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor mediates many biological processes. Herein, we investigated if 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE, an endogenous AhR ligand) regulated proliferation and migration of human ovarian cancer cells via AhR. We found that AhR was widely present in many histotypes of ovarian cancer tissues. ITE suppressed OVCAR-3 cell proliferation and SKOV-3 cell migration in vitro, which were blocked by AhR knockdown. ITE also suppressed OVCAR-3 cell growth in mice. These data suggest that the ITE might potentially be used for therapeutic intervention for at least a subset of human ovarian cancer. PMID:23851185

Wang, Kai; Li, Yan; Jiang, Yi-Zhou; Dai, Cai-Feng; Patankar, Manish S; Song, Jia-Sheng; Zheng, Jing

2013-07-09

 
 
 
 
21

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

Science.gov (United States)

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

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

2013-02-13

22

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

UK PubMed Central (United Kingdom)

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.

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

2013-01-01

23

Hydrocarbon gases at eastern Mediterranean mud expulsion structures: origin, migration, and water column expression  

Science.gov (United States)

In the eastern Mediterranean a variety of different mud expulsion structures is found on the seafloor at passive and continental margins, all of which appear to have active emission of hydrocarbon gases. The eruptions are thought to be triggered by the overpressure occurring at depth and resulting from excess gas and water pressure. Gas, fluids, and sediments are then mobilized and migrate through the sedimentary column (often via faults), building mud domes. At all mud structures investigated in the eastern Mediterranean, not only enhanced concentrations of methane, but also of ethane, and propane, have been observed in the sediment, and in the water column. The water column gas plumes extend up to several hundreds of meters above the seafloor and even reach the sea surface. These gas plumes are associated with enhanced light scattering, which can be associated to the release of gas bubbles and/or sedimentary particles. Part of the hydrocarbons may have been altered by (microbial) oxidation. The signature of the gases that resembles most the initial composition can be found in the deepest core samples. Several of the water column plumes closely resemble these, thereby confirming their direct emission via bubble transport into the water column. On the basis of gas concentrations and isotope composition, a thermogenic origin with a smaller but variable biogenic contribution can be deduced for the hydrocarbon gases at most mud expulsion structures. This work has been supported by the EUROMARGINS Programme of the European Science Foundation NWO. 85501032 Mediflux project).

Mastalerz, V.; de Lange, G. J.; Daehlmann, A.

2009-04-01

24

CATALYST FOR THE DEHYDROGENATION OR HYDROGENATION OF HYDROCARBONS CONTAINING SECONDARY CATALYST MATERIAL  

UK PubMed Central (United Kingdom)

The invention relates to a catalyst for the dehydrogenation or hydrogenation of hydrocarbons containing between 10 and 70 wt. % milled, secondary catalyst material of a used (de)hydrogenation catalyst that contains iron oxide and between 30 and 90 wt. % of the corresponding fresh catalyst material containing iron oxide, said iron oxide of the fresh catalyst material being predominantly in the form of hematite or potassium ferrite. The invention also relates to a method for producing the catalyst and to a method for dehydrogenating or hydrogenating hydrocarbons using the catalyst provided by the invention.

WALSDORFF CHRISTIAN; HOUSSIN CHRISTOPHE; VORBERG GERALD; KOERNER REINHARD; HOFSTADT OTTO

25

Hydrocarbon generation and migration in the Nanpu Sag, Bohai Bay Basin, eastern China: Insight from basin and petroleum system modeling  

Science.gov (United States)

The hydrocarbon generation and migration history occurred in the Nanpu Sag, Bohai Bay Basin was investigated using basin and petroleum system modeling. The Eocene Es34 and Es1 members/submembers of the Shahejie Formation and the Oligocene Ed3 member of the Dongying Formation are the most important source rocks responsible for the major hydrocarbon accumulations in Nanpu Sag. One and two-dimensional basin modeling was performed to unravel the hydrocarbon generation and migration history of the three sets of source rocks based on the reconstruction of the burial, thermal, maturity and fluid potential history. The model was calibrated with thermal maturity and borehole temperature data and simulated results indicate that Es34, Es1, and Ed3 source rocks in Laoyemiao and Caofeidian sub-sags reached peaks of hydrocarbon generation at about 20 Ma, 10 Ma, and 0 Ma respectively. The fluid potential and flow line modeling revealed that nearly all the structural high were directions of hydrocarbon migration and formed favorable traps for whichever of the source rock strata. Multiple sub-sags oil-offering and compound faults caused oil mixture.

Guo, Yingchun; Pang, Xiongqi; Dong, Yuexia; Jiang, Zhenxue; Chen, Dongxia; Jiang, Fujie

2013-11-01

26

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

Directory of Open Access Journals (Sweden)

Full Text Available Vanadio, níquel y porfirinas como trazadores de rutas de migración secundaria del petróleo: Cuenca del lago de Maracaibo, VenezuelaA 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.

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

2007-01-01

27

Geopressure evolution, hydrocarbon generation and migration in the Beaufort-Mackenzie Basin, Canada: results from two-dimensional quantitative modelling  

Energy Technology Data Exchange (ETDEWEB)

Three cross-sections of onshore and offshore areas of the Beaufort-MacKenzie Basin were used to simulate geopressure evolution, hydrocarbon generation and migration processes of the Tertiary section using a two-dimensional model. The model results indicate that the present day distributions of geopressure and maturity levels at different locations have been modified by late Miocene uplift and erosion, followed by rapid deposition of the late Miocene-Pleistocene lperk sediments. Although the occurrence of oil and gas has no obvious relationship to geopressure at the present day, the evolution of geopressure in strata older than the Mackenzie sequence plays an important part in the maturation of Tertiary source rocks. Geopressure in these older formations caused an increase in thermal gradient and porosity in the deep formations. The analysis indicates that the timing of hydrocarbon generation and the evolution of geopressure are critical factors in the development of horizontal migration (Reindeer reservoirs) versus vertical migration (Kugmallit reservoirs). (Author)

Jie Tang; Lerche, I. (South Carolina Univ., Columbia, SC (United States). Dept. of Geological Sciences)

1993-08-01

28

Clinical outcomes following secondary self-expandable metal stent (SEMS) insertion due to previous stent migration in malignant colorectal obstruction.  

UK PubMed Central (United Kingdom)

BACKGROUND: There has been no research on the clinical outcomes of secondary self-expandable metal stent (SEMS) placement after initial stent migration. Therefore, this study aimed to assess the clinical outcomes of secondary SEMS placement after initial stent migration compared to the outcomes of secondary SEMS placement done for reasons other than migration and identify factors predictive of long-term outcomes. METHODS: Between January 2005 and February 2011, a total of 422 patients underwent SEMS insertion for malignant colorectal obstruction at Severance Hospital. Of these, there were 98 cases of secondary SEMS placement, 38 of which were due to previous stent migration. We compared the clinical outcomes of secondary SEMS between stent migration and nonmigration groups. We also sought to identify risk factors for long-term outcomes of secondary SEMS after initial stent migration. RESULTS: The baseline clinical characteristics were similar between the two groups. The technical and clinical success rates of secondary SEMS insertion in the migration and nonmigration groups were 94.7 % and 83.3 % (p = 0.09) and 73.7 % and 53.3 % (p = 0.122), respectively. In the migration group, sustained clinical success after secondary SEMS was associated with the absence of complications after insertion of the first stent (p < 0.001) and a longer time interval (more than 100 days) between the first and second stent insertion (p = 0.011). CONCLUSIONS: Our data showed that secondary colorectal SEMS after stent migration is safe and effective. Moreover, the sustained clinical success of the secondary stent following migration was dependent on the outcomes of the first stent.

Choi AR; Yoon JY; Lee HJ; Jang HW; Park SJ; Hong SP; Kim TI; Kim WH; Cheon JH

2013-09-01

29

Fluid and hydrocarbon migration at active margins: A conceptual synthesis of results from the Barbados Ridge and Pacific northwest  

Energy Technology Data Exchange (ETDEWEB)

At active convergent margins, offscraped sediments are imbricated at the deformation front and mature with attendant loss of fluids. Underthrust sediments slide beneath the accretionary prism at the velocity of the oceanic plate and continuously release fluids and/or hydrocarbons during descent. The continuous renewal of sediment by underthrusting beneath the accretionary prism suggests large cumulative fluid and hydrocarbon flux beneath any area of the prism. The asymmetrical loading of underthrust sediments by the tapered accretionary prism causes updip migration of fluids and hydrocarbons through stratigraphic conduits or the decollement zone at the base of the accretionary prism. Probable thermogenic hydrocarbons indicate long-distance lateral migration along these conduits from beneath the Barbados prism. Pore-water and temperature anomalies (Barbados) and biological indicators of fluid expulsion (Oregon) indicate that faults effectively capture fluid flow from the underthrust sequence (Barbados) and permeable sedimentary layers within the accretionary prisms (Oregon). Permeability measurements and hydrogeological modeling indicate that fault-capture of fluids requires permeabilities two to five orders of magnitude higher in the fault zones than in the source sediments. Complex deformation and diagenesis in accretionary prisms rapidly destroys the continuity of permeable stratigraphic conduits; faults become the principal migration conduits. The basinward growth of accretionary prisms require that they deform internally, commonly by out-of-sequence thrust; such thrusts may be migration conduits connecting underthrust or underplated source sediments to shallow reservoirs. Both in Barbados prism and the Pacific Northwest, out-of-sequence thrusts leak hydrocarbons and could feed reservoirs in overlying slightly deformed shelf and basinal sequences.

Moore, J.C.; Orange, D.; Stiles, S.; Geddes, D. (Univ. of California, Santa Cruz (USA))

1990-05-01

30

Aspects of generation and migration of hydrocarbons from coal-bearing strata of the Hitra formation, Haltenbanken area, offshore Norway  

Energy Technology Data Exchange (ETDEWEB)

The Haltenbanken area, situated 150-200 km offshore mid-Norway is a proven gas/condensate and oil producing province with continuing exploration potential. In this structurally and stratigraphically complex area with multiple source rock possibilities, the Upper Triassic/Lower Jurassic Hitra formation has been examined to determine its possible contribution to the hydrocarbon pools in the area. The 400m thick Hitra formation consists of interbedded shales, siltstones, sandstones and coal seams. In this study conventional cores of the Hitra formation from depths varying from 2.4. and 4.6 km have been examined with the objective to obtain a better understanding of hydrocarbon generation, migration and expulsion processes in these coals as a function of variation in facies and maturity. In addition to basic geochemical measurements (TOC, Rock-Eval and GC analysis of C15+ saturated hydrocarbons), microscopic studies (normal and UV reflected light) were carried out to determine the abundance and initial distribution of hydrogen rich macerals including fluorescent mobile phases such as exsudatinites. Geochemical and microscopic evidence was obtained suggesting that some of the interbedded sandstones show indications of impregnation by migrated hydrocarbons. Some bitumen filled micro fractures were observed extending from the coals towards the adjacent sands. A preliminary interpretation of these data is that these fractures represent conduits carrying hydrocarbons from the coal seams towards the sandstones. The role of the kerogen type variations on the amount of hydrocarbons generated and the mechanism and efficiency of hydrocarbon expulsion from the coals is discussed. 27 refs., 6 figs., 1 tab.

Hvoslef, S.; Larter, S.R.; Leythaeuser, D.

1988-01-01

31

The use of migration barriers to prevent the spread of petroleum hydrocarbons  

International Nuclear Information System (INIS)

[en] Contaminant containment at a remediation site can be achieved in several ways, depending upon the geochemical characteristics of the site, the nature and intensity of the contamination, and the phase distribution of the contaminants. In sites involving a contamination solute plume in groundwater, the containment issue has classically been achieved with some form of hydraulic extraction system, where elevation gradients have been achieved by pumps in vertical (or horizontal) wells. Plumes of solute contaminants in the aquifer have been captured by closure of the flow lines at the extraction well(s) location and the extracted water transported to a treatment system for removal of the dissolved contaminant species. While frequently referred to as ''pump and treat,'' such systems are not true treatment concepts and usually fail to address the ''source'' which exists upgradient in the form of oily-phase ''free'' adsorbed or entrained phases in the aquifer material itself. The use of air sparging techniques to effect both physical removal and biological degradation and the use of a row of wells containing a slow release oxygen compound are discussed as methods of mitigating migration of monoaromatic hydrocarbons (BTEX) and other volatile and/or aerobically biodegradable contaminants

1995-01-01

32

Microbiota associated with the migration and transformation of chlorinated aliphatic hydrocarbons in groundwater.  

UK PubMed Central (United Kingdom)

Pollution of groundwater with chlorinated aliphatic hydrocarbons (CAHs) is a serious environmental problem which is threatening human health. Microorganisms are the major participants in degrading these contaminants. Here, groundwater contaminated for a decade with CAHs was investigated. Numerical simulation and field measurements were used to track and forecast the migration and transformation of the pollutants. The diversity, abundance, and possible activity of groundwater microbial communities at CAH-polluted sites were characterized by molecular approaches. The number of microorganisms was between 5.65E+05 and 1.49E+08 16S rRNA gene clone numbers per liter according to quantitative real-time PCR analysis. In 16S rRNA gene clone libraries constructed from samples along the groundwater flow, eight phyla were detected, and Proteobacteria were dominant (72.8 %). The microbial communities varied with the composition and concentration of pollutants. Meanwhile, toluene monooxygenases and methane monooxygenases capable of degradation of PCE and TCE were detected, demonstrating the major mechanism for PCE and TCE degradation and possibility for in situ remediation by addition of oxygen in this study.

Guan X; Liu F; Xie Y; Zhu L; Han B

2013-08-01

33

Saline fluid flow and hydrocarbon migration and maturation as related to geopressure, Frio Formation, Brazoria County, Texas  

Energy Technology Data Exchange (ETDEWEB)

The Pleasant Bayou geopressured-geothermal test wells in Brazoria County, Texas, display a prominent thermal-maturity anomaly in the Oligocene Anahuac and Frio Formations. Highly geopressured, more-mature shales are interbedded with hydropressured to moderately geopressured sandstones in the upper Frio and Anahuac. In contrast, shales and sandstones in the lower Frio, including the Andrau geopressured-geothermal production zone, are highly geopressured but exhibit lower thermal maturities. Vitrinite-reflectance data, supported by hydrocarbon-maturation data and anomalous concentrations of C/sub 5/ to C/sub 7/ hydrocarbons at Pleasant Bayou, indicate that the upper Frio was subjected to an extended period of hot, extremely saline, basinal fluid flow which caused the above thermal anomaly. Regional salinity studies (Morton and others, 1983) suggest that regional growth faults were the conduits for vertical basinal brine movement at depth. At shallower levels the upwelling waters migrated laterally through permeable sandstone-rich sections such as the upper Frio. Anomalously mature gasoline-range (C/sub 5/-C/sub 7/) hydrocarbons were introduced into the upper Frio by this process. Fluid influx in the lower Frio was probably limited by high geopressure, consequently maturity in the deep Frio section (greater than 14,000 ft) remained consistent with the regional geothermal gradient.

Tyler, N.; Light, M.P.R.; Ewing, T.E.

1985-01-01

34

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

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish Vanadio, níquel y porfirinas como trazadores de rutas de migración secundaria del petróleo: Cuenca del lago de Maracaibo, Venezuela Se propone un modelo de migración secundaria para el yacimiento Marcelina (Paleoceno) del campo Alturitas, Cuenca del Lago de Maracaibo, Venezuela. Para ello, se utilizaron diversos parámetros relacionados con metales trazas y biomarcadores, extraídos en 30 muestras que fueron sometidas a diferentes análisis (SARA, CG-EM, ICP-OES (more) y UV-Vis.). Partiendo de la premisa que estas muestras de crudo pertenecen a un mismo tipo genético [1-2], se analizaron los cambios en las concentraciones y distribuciones areales de los diferentes parámetros bajo estudio. Se registraron 10 metales traza, subdivididos en dos grupos; el primero no presenta comportamientos que puedan ser asociados al proceso de migración sino que más bien indica una asociación calcófila (Cd, Cu, Mo y Zn) o posible presencia de ácidos nafténicos formando partículas coloidales (Ca, Mg, Fe). El segundo, que incluye vanadio, níquel, porfirinas y las concentraciones de resinas más asfaltenos en crudo total, responde al proceso de cromatografía natural, por lo cual permite la proposición de una ruta de migración secundaria de los crudos del posible yacimiento Rev. Téc. Ing. Univ. Zulia. Vol. 30, Edición Especial, 2007 con un eje preferencial orientado sur-norte. El análisis de diferentes biomarcadores no arrojó resultados claros en cuanto a la caracterización del proceso de migración y acumulación en el yacimiento. 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 stud (more) ied. 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.

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

2007-11-01

35

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

International Nuclear Information System (INIS)

[en] 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.)[pt] Analisa-se a composicao isotopica do carbono de gases naturais para determinar a origem e migracao de hidrocarbonetos gasosos das bacias sedimentares brasileiras. A razao isotopica do carbono do metano de gases naturais depende do processo de formacao e do estagio de maturacao da materia organica. Na exploracao geoquimica de superficie os gases bioquimicos sao diferenciados dos gases termoquimicos, por estes ultimos serem mais pesados. Como a composicao isotopica do metano nao varia durante a migracao, os gases migrados de profundidades maiores e de rochas geradoras mais maturas sao identificados pelo seu relativo enriquecimento em 13C. O metano foi separado dos outros gases presentes por cromatografia e a analise isotopica foi feita com um espectrometro de massa. (Autor)

1986-01-01

36

Effectiveness of phytoremediation as a secondary treatment for polycyclic aromatic hydrocarbons (PAHs) in composted soil.  

UK PubMed Central (United Kingdom)

A greenhouse study was conducted over a 12-month period to investigate the fate of polycyclic aromatic hydrocarbons (PAHs) in soil using phytoremediation as a secondary treatment. The soil was pretreated by composting for 12 weeks, then planted with tall fescue (Festuca arundinacea), annual ryegrass (Lolium multiflorum), and yellow sweet clover (Melilotus officinalis). Two sets of unvegetated controls also were evaluated, one fertilized and one unfertilized. Total PAH concentrations decreased in the tall fescue, annual ryegrass, and yellow sweet clover treatments by 23.9%, 15.3%, and 9.1%, respectively, whereas the control was reduced by less than 5%. The smaller two- and most of the three-ringed compounds--naphthalene, acenaphthylene, acenaphthene, fluorene, and anthracene--were not found in detectable concentrations in any of the treatments. The most probable number analysis for microbial PAH degraders did not show any statistically significant differences among treatments. There were significant differences among treatments (p < 0.05) for the residual concentrations of five of the target PAHs. Root surface area measurements indicated that tall fescue and annual ryegrass both had significantly higher root surface area than yellow sweet clover, although the two species were not significantly different from each other. The tall fescue treatment resulted in the highest root and shoot biomass, followed by annual ryegrass and yellow sweet clover, and also had the highest percent of contaminant removal after 12 months. These results imply a positive relationship between plant biomass development and PAH biodegradation.

Parrish ZD; Banks MK; Schwab AP

2004-01-01

37

Effectiveness of phytoremediation as a secondary treatment for polycyclic aromatic hydrocarbons (PAHs) in composted soil.  

Science.gov (United States)

A greenhouse study was conducted over a 12-month period to investigate the fate of polycyclic aromatic hydrocarbons (PAHs) in soil using phytoremediation as a secondary treatment. The soil was pretreated by composting for 12 weeks, then planted with tall fescue (Festuca arundinacea), annual ryegrass (Lolium multiflorum), and yellow sweet clover (Melilotus officinalis). Two sets of unvegetated controls also were evaluated, one fertilized and one unfertilized. Total PAH concentrations decreased in the tall fescue, annual ryegrass, and yellow sweet clover treatments by 23.9%, 15.3%, and 9.1%, respectively, whereas the control was reduced by less than 5%. The smaller two- and most of the three-ringed compounds--naphthalene, acenaphthylene, acenaphthene, fluorene, and anthracene--were not found in detectable concentrations in any of the treatments. The most probable number analysis for microbial PAH degraders did not show any statistically significant differences among treatments. There were significant differences among treatments (p sweet clover, although the two species were not significantly different from each other. The tall fescue treatment resulted in the highest root and shoot biomass, followed by annual ryegrass and yellow sweet clover, and also had the highest percent of contaminant removal after 12 months. These results imply a positive relationship between plant biomass development and PAH biodegradation. PMID:15328979

Parrish, Zakia D; Banks, M Katherine; Schwab, A Paul

2004-01-01

38

Migration of hydrocarbons in the subsoil of an industrial installation; Migration d'hydrocarbures dans le sous-sol d'une installation industrielle  

Energy Technology Data Exchange (ETDEWEB)

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)

Van Dorpe, F. [CEA Cadarache, Dept. d' Entreposage et de Stockage des Dechets (DCC/DESD/SEP), 13 - Saint-Paul-lez-Durance (France); Centre National de Recherche sur les Sites et Sols Pollues (CNRSSP), 59 - Douai (France)

2000-07-01

39

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

Energy Technology Data Exchange (ETDEWEB)

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.

Catherine L. Hanks

2008-12-31

40

Geological conditions and geochemical effects of secondary petroleum migration and accumulation  

Energy Technology Data Exchange (ETDEWEB)

The processes of secondary petroleum migration and reservoir filling remain among the least understood steps with respect to the characterisation and economic assessment of a petroleum system. Spatial heterogeneities of compositions of unaltered petroleum within individual fields have repeatedly been recognised and interpreted to result from compositional changes of multiple petroleum charges during the accumulation history in combination with limited degree of in-reservoir mixing of petroleum fluids (England, W. A., Mackenzie, A. S., Mann, D. U.,and Quigley T. M. (1987). The movement and entrapment of petroleum fluids in the subsurface. J. Geol. Soc. London 144, 327-347; Leythaeuser, D., and Rueckheim, J. (1989). Heterogeneity of oil composition within a reservoir as a reflection of accumulation history. Geochim. Cosmochim. Acta, 53(8), 2119-2123). Most previous attempts, to improve this situation, have aimed at an understanding of the conditions and effects of the flow of petroleum fluids by studying case histories on regional or field scales. In the study reported here we have, in addition, attempted to reconstruct the mode of filling of sandstone reservoir rocks on pore scales. (author)

Leythaeuser, D.; Schwark, L.; Keuser, Ch. [Koln Univ. (Germany). Geologisches Inst.

2000-08-01

 
 
 
 
41

An experimental investigation of geochromatography during secondary migration of petroleum performed under subsurface conditions with a real rock  

Directory of Open Access Journals (Sweden)

Full Text Available An understanding of the size of petroleum secondary migration systems is vital for successful exploration for petroleum reserves. Geochemists have suggested that compositional fractionation of petroleum accompanying the migration process (geochromatography) can potentially be used to infer distances petroleum may have travelled and the ratio of oil in the reservoir to that lost in the carrier. To date, this has been attempted by measuring concentrations and distributions of specific steranes, and aromatic oxygen and nitrogen compounds in reservoired oils which have been proposed to respond to migration rather than to source maturity or other effects. We report here an experiment involving oil migration through an initially water wet siltstone under realistic subsurface carrier bed or reservoir conditions (48 MPa, 70°C) where source facies and maturity effects are eliminated. We show that geochromatography does indeed occur even for initially water-saturated rocks and that the migration fractionations observed for alkylcarbazoles, benzocarbazoles and alkylphenols are very similar to those seen in field data sets. In contrast, sterane based migration parameters show no compositional fractionation under these conditions.

Larter Steve; Bowler Berni; Clarke Ed; Wilson Colin; Moffatt Brian; Bennett Barry; Yardley Gareth; Carruthers Dan

2000-01-01

42

An evaluation of cases of pneumonia that occurred secondary to hydrocarbon exposure in children.  

UK PubMed Central (United Kingdom)

OBJECTIVE: Hydrocarbon pneumonia is distinct among the types of childhood pneumonia in that it has a different pathogenesis and treatment and is preventable. In this study, the cases of 54 children with hydrocarbon pneumonia admitted to the Dicle University Medical Faculty Pediatric Chest Diseases Unit between the years 2006 and 2010 were analyzed retrospectively. PATIENTS AND METHODS: The medical records of 54 patients diagnosed with pneumonia after ingesting/inhaling hydrocarbons were analyzed retrospectively. Age, sex, presenting symptoms, clinical status, radiological and laboratory findings and response to treatment and prognosis were noted. RESULTS: 35 (64.8%) of the patients were male, 19 (35.2%) were female and the ages of the patients ranged from 1 to 5 with an average of 2.49 ± 0.80. The etiologies of the pneumonia were thinner (33%), naphta (3.7%) and kerosene. In 49 of the patients (90.7%), the symptoms started to occur the day the patient was exposed to hydrocarbons. The average length of hospital stay was 4.0 ± 2.3 days. Six patients were treated in the intensive care unit (ICU), and one patient with hydrocarbon pneumonia due to kerosene ingestion died. Inhaled corticosteroids were administered to 18 patients who were progressively deteriorating and inhaled salbutamol was given to 16 patients with bronchospasm. Patients with radiological findings on their chest X-rays and auscultatory findings were found to have longer hospital stays (p < 0.05). CONCLUSIONS: To prevent chemical pneumonia, precautions must be taken to stop children under 5 years of age from using/abusing chemical substances. Although some cases of chemical pneumonia lead to death, with diligent care and treatment, the outcomes are promising. The patients in this study group responded well to treatment with inhaled corticosteroids and salbutamol.

Sen V; Kelekci S; Selimoglu Sen H; Yolbas I; Günes A; Abakay O; Fuat Gurkan M

2013-02-01

43

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)

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.

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

2006-01-01

44

A study of hydrocarbon migration events: Development and application of new methods for constraining the time of migration and an assessment of rock-fluid interactions. Final report, September 1, 1991--August 31, 1994  

Energy Technology Data Exchange (ETDEWEB)

The authors are conducting the research to test and refine a paleomagnetic method for dating hydrocarbon migration, and to assess the chemical alteration of crude oils resulting from fluid-rock interactions. Samples were collected for paleomagnetic and organic geochemical investigations from several units. These include the Old Red Sandstone in Scotland, and the Schoolhouse Member of the Maroon Formation and the Belden Formation in Colorado. Studies of these units are completed or underway. In addition, simulation experiments, where the authors are attempting to form magnetite in the laboratory, are underway.

Elmore, R.D.; Engel, M.H.

1993-12-31

45

Role of capillary-emulsion effects in processes of secondary migration in accumulation of petroleum  

Energy Technology Data Exchange (ETDEWEB)

The physical principles of the emulsification of single-bound petroleum during movement of its front in a water saturated capillary-porous medium are investigated. It is shown that there must be emulsion of the residual petroleum saturation in progressive emulsion which outruns the front of solid petroleum during the movement of petroleum pillars. A stage-wise filtration-mechanism of the streamline migration of petroleum is proposed on this basis.

Grishkevich, V.F.

1981-01-01

46

[Vesicourethral anastomotic stricture after radical prostatectomy secondary to migration of a metal clip].  

UK PubMed Central (United Kingdom)

The frequency of vesicourethral anastomotic stricture after prostatectomy is estimated to be 14%, an average of 3 months after the operation. The authors report the cases of a 61-year-old man undergoing radical prostatectomy for localized prostate cancer. The postoperative course was marked by recurrent urinary retention and several urethrotomies failed to restore spontaneous voiding. A clip was finally visualized and removed by endoscopy. The patient has not experienced any further episodes of retention. This is the first published cases of clip migration responsible for anastomotic stricture after radical prostatectomy. This diagnosis must be considered in the case of repeated postoperative retention.

Long B; Bou S; Bruyere F; Lanson Y

2006-06-01

47

Basin modeling and hydrocarbon exploration  

Energy Technology Data Exchange (ETDEWEB)

The generation, migration and accumulation of oil and gas are a series of dynamic processes linked to the evolution of sedimentary basins. A sedimentary basin is formed by very complex interrelated processes, which form a multiparameter dynamic system. Therefore, evaluation and prediction of the hydrocarbon potential of a basin requires an accurate and quantified reconstruction of the relevant processes. Computer-aided, integrated basin modeling on the basis of numerical simulation enables such a reconstruction. Processes which should be either simulated or considered in a forward modeling approach, aiming to predict the location and type of hydrocarbon accumulations are discussed. Additionally, parameters which are required for a reliable simulation of different processes, such as sediment accumulation, compaction, fluid flow and pressure development, transfer of heat, basin deformation, oil and gas generation, oil expulsion and secondary migration are evaluated. Furthermore, with the help of simulated case histories the close interrelations between different parameters are demonstrated. 14 figs., 1 tab., 74 refs.

Yalcin, M.N. (TUEBITAK, Marmara Research Center, Gebze-Kocaeli (Turkey))

1991-06-01

48

Liver abscess secondary to a broken needle migration- A case report  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Perforation of gut by sharp metallic objects is rare and rarer still is their migration to sites like liver. The symptoms may be non-specific and the discovery of foreign body may come as a radiological surprise to the unsuspecting clinician since the history of ingestion is difficult to obtain. Case report A unique case of a broken sewing needle in the liver causing a hepatic abscess and detected as a radiological surprise is presented. The patient had received off and on treatment for pyrexia for the past one year at a remote primary health center. Exploratory laparotomy along with drainage of abscess and retrieval of foreign body relieved the patient of his symptoms and nearly one-year follow up reveals a satisfactory recovery. Conclusion It is very rare for an ingested foreign body to lodge in the liver and present as a liver abscess. An ultrasound and a high clinical suspicion index is the only way to diagnose these unusual presentations of migrating foreign bodies. The management is retrieval of the foreign body either by open surgery or by percutaneous transhepatic approach but since adequate drainage of the abscess and ruling out of a fistulous communication between the gut and the liver is mandatory, open surgery is preferred.

Chintamani; Singhal Vinay; Lubhana Parminder; Durkhere Rakesh; Bhandari Shabnam

2003-01-01

49

Secondary aerosol formation from the oxidation of biogenic hydrocarbons by chlorine atoms  

Science.gov (United States)

The chlorine atom (Cl) is a potential oxidant of volatile organic compounds (VOCs) in the atmosphere and is hypothesized to lead to secondary organic aerosol (SOA) formation in coastal and industrialized areas. The purpose of this paper is to test this hypothesis and to quantify the SOA formation potentials of the common monoterpenes ?-pinene, ?-pinene, and d-limonene when oxidized by Cl in laboratory chamber experiments. Results indicate that the oxidation of these monoterpenes generates significant amounts of aerosol. The SOA yields of ?-pinene, ?-pinene, and d-limonene in this study are comparable to those when they are oxidized by ozone, by nitrate radical, and in photooxidation scenarios. For aerosol mass up to 30.0 ?g m-3, their yields reach approximately 0.20, 0.20, and 0.30, respectively. For d-limonene, data indicate two yield curves that depend on the initial concentration ratio of Cl precursor to d-limonene. It is argued theoretically that multiple SOA yield curves may be common for VOCs, depending on the initial concentration ratio of oxidant to VOC. SOA formation from the three typical monoterpenes when oxidized by Cl in the marine boundary layer, coastal areas, and inland industrialized areas could be a source of organic aerosol in the early morning.

Cai, Xuyi; Griffin, Robert J.

2006-07-01

50

Proof-of-concept study of an aerobic vapor migration barrier beneath a building at a petroleum hydrocarbon-impacted site.  

UK PubMed Central (United Kingdom)

A proof-of-concept study was conducted to evaluate an alternative to traditional extraction-based subslab vapor mitigation systems at sites with petroleum hydrocarbon and/or methane vapor impact concerns. The system utilizes the slow delivery of air beneath a foundation to attenuate vapor migration to the building via aerobic biodegradation. The study was conducted at a site having elevated hydrocarbon plus methane and depleted O(2) vapor concentrations (160 mg/L and <1% v/v, respectively) beneath a building having a 195 m(2) footprint and a basement extending 1.5 m below ground surface (BGS). Nonaqueous phase liquid (NAPL)-impacted soils, first encountered at about 7.6 to 9.1 m BGS, were the source of hydrocarbon and methane vapors, with the latter being generated by anaerobic methanagenesis of the former. O(2) concentrations beneath and around the building were monitored prior to and during air injection through a horizontal well installed about 1.5 m beneath the foundation. The air injection rate was increased from 1 to 5 to 10 L/min, with each held steady until the O(2) distribution stabilized (46-60 d). The 10 L/min flow rate achieved >5% v/v soil gas O(2) concentrations beneath the foundation and spanning a 1.5 m vertical interval. It was within 3× of the pretest stoichiometric requirement estimate of 3.8 L/min. This resulted in reductions in subslab hydrocarbon plus methane concentrations from 80 to <0.01 mg/L and benzene, toluene, ethylbenzene, and xylenes (BTEX) reductions to below detection limits (0.5-0.74 ppb(v)). This air injection rate is <1% of flows for typical extraction-based mitigation systems.

Luo H; Dahlen PR; Johnson PC; Peargin T

2013-02-01

51

Secondary migration routes in the Brent sandstones of the Viking graben and east Shetland basin: Evidence from oil residues and subsurface pressure data  

Energy Technology Data Exchange (ETDEWEB)

The Viking Graben of the North Sea contains a major deltaic reservoir - the Brent Group. Within the Brent Group, the Etive Formation, a coastal barrier sand, is both areally continuous and has excellent porosity and permeability. It is sandwiched between the fine-grained micaceous sandstones of the Rannoch Formation below and the impermeable mudstones of the Ness Formation above. Consequently, the Etive Formation has acted as the most important regional conduit for secondary migration of Upper Jurassic sourced oils. Oil migration through time has left a heavy residue in the uppermost part of the formation. These residues are aromatic-asphaltic, but otherwise resemble locally reservoired oils. Migration-sensitive biological marker ratios obtained from the residues change with distance from source. Secondary migration route mapping, based on the movement of oil by buoyancy in well-defined, isolated pressure compartments, integrated with timing of oil generation, indicates that the Ninian field could be sourced from two areas - Late Cretaceous migration from the southeast in the Viking Graben and Tertiary migration from the west and southwest - explaining some of the contrasting reservoir and oil characteristics of the Ninian and Lyell fields. 15 figs., 1 tab.

Miles, J.A. (Univ. of Reading (England))

1990-11-01

52

Geochemistry of oils and hydrocarbon source rocks, greater Anadarko Basin: evidence for multiple sources of oils and long-distance oil migration  

Science.gov (United States)

Organic geochemical analyses of 104 crude oils and 190 core samples of dark-colored shales from the greater Anadarko basin show three major oil types which generally correlate with reservoir age and source-rock age. Analyses include C3-C30 whole-oil gas chromatography, C10+ saturated-hydrocarbon-fraction gas chromatography, and carbon stable isotopes (ppt relative to PDB) of saturated (sat) and aromatic (arom) hydrocarbon fractions. Three samples from Middle Ordovician Simpson Group reservoirs are "typical" Ordovician oils (type 1), having strong odd-carbon predominance in the C13 to C19 n-alkanes, containing little or no acyclic isoprenoids, an ?13C values of -33.9 ppt (sat) and -33.7 ppt (arom). Oils from Silurian to Devonian and Mississippian reservoirs (type 2) show little or no odd-carbon predominance in the n-alkanes, a regular decrease in abundance of n-alkanes with increasing carbon number, pristane/phytane ratios (pr/ph) of 1.1 to 1.5, and ?13C values of -30.6 ppt (sat) and -30.1 ppt (arom). Oils in Pennsylvanian reservoirs (type 3) have the greatest amounts of C15+ hydrocarbons, are isotopically heavy (-27.5 ppt [sat] and -26.4 ppt [arom]), have methyl-cyclohexane as the most abundant hydrocarbon, and have pr/ph values from 2.0 to 0.9. Oils from the Kansas shelf area of the Anadarko basin are similar to the Anadarko oil types except that they have only traces of toluene and no detectable benzene. The relative abundance of toluene in the C7 hydrocarbons systematically decreases with distance from the depocenter of the basin. The aromatic compounds are removed by water-washing, and hence could have been lost by contact with progressively greater amounts of formation water during long-distance migration. The lack of thermally mature source rocks in southern and central Kansas supports this hypothesis.

Burruss, R. C.; Hatch, J. R.

1989-01-01

53

Optimization and Pharmacological Validation of a Leukocyte Migration Assay in Zebrafish Larvae for the Rapid In Vivo Bioactivity Analysis of Anti-Inflammatory Secondary Metabolites  

Science.gov (United States)

Over the past decade, zebrafish (Danio rerio) have emerged as an attractive model for in vivo drug discovery. In this study, we explore the suitability of zebrafish larvae to rapidly evaluate the anti-inflammatory activity of natural products (NPs) and medicinal plants used in traditional medicine for the treatment of inflammatory disorders. First, we optimized a zebrafish assay for leukocyte migration. Inflammation was induced in four days post-fertilization (dpf) zebrafish larvae by tail transection and co-incubation with bacterial lipopolysaccharides (LPS), resulting in a robust recruitment of leukocytes to the zone of injury. Migrating zebrafish leukocytes were detected in situ by myeloperoxidase (MPO) staining, and anti-inflammatory activity was semi-quantitatively scored using a standardized scale of relative leukocyte migration (RLM). Pharmacological validation of this optimized assay was performed with a panel of anti-inflammatory drugs, demonstrating a concentration-responsive inhibition of leukocyte migration for both steroidal and non-steroidal anti-inflammatory drugs (SAIDs and NSAIDs). Subsequently, we evaluated the bioactivity of structurally diverse NPs with well-documented anti-inflammatory properties. Finally, we further used this zebrafish-based assay to quantify the anti-inflammatory activity in the aqueous and methanolic extracts of several medicinal plants. Our results indicate the suitability of this LPS-enhanced leukocyte migration assay in zebrafish larvae as a front-line screening platform in NP discovery, including for the bioassay-guided isolation of anti-inflammatory secondary metabolites from complex NP extracts.

Vicet-Muro, Liliana; Wilches-Arizabala, Isabel Maria; Esguerra, Camila V.; de Witte, Peter A. M.; Crawford, Alexander D.

2013-01-01

54

[Biological monitoring of exposure to carcinogenic metallic elements and polycyclic aromatic hydrocarbons in four secondary metallurgical sectors].  

UK PubMed Central (United Kingdom)

This cross-sectional study was aimed at evaluating in a large sample of male foundry workers the current exposure levels to carcinogenic compounds, including metallic elements [arsenic (As), beryllium (Be), cadmium (Cd), chromium (Cr), nickel (Ni)] and aromatic polycyclic hydrocarbons (PAH) by a biological monitoring approach, using validated biomarkers of exposure. Workers were recruited from 15 aluminium, copper alloy, electric steel and cast iron foundries and provided an end-of-shift urine sample to determine urinary concentrations of As, Be, Cd, Cr, Ni and 1-hydroxypyrene (1-OHP). Metallic elements were determined either by inductively coupled plasma mass spectrometry (Be, Cd and Cr) or by atomic absorption spectrometry (As, Ni), whereas 1-OHP was determined by high pressure liquid chromatography with fluorimetric detection. Most of the determinations fell within the laboratory's reference values. Age and lifestyle habits (smoking, alcohol, diet) played a significant interfering role.

De Palma G; Corsini A; Gilberti E; Gabusi V; Tagliani G; Tomasi C; Gandellini A; Apostoli P

2012-07-01

55

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

Science.gov (United States)

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

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

2008-04-15

56

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

UK PubMed Central (United Kingdom)

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.

Wenger D; Gerecke AC; Heeb NV; Zennegg M; Kohler M; Naegeli H; Zenobi R

2008-04-01

57

Cyclicity of the geotectonic-geothermal cycle of rocks and its influence on conditions of generation and migration of hydrocarbons in Paleozoic deposits of the North Ural-Trans-Volga Region  

Energy Technology Data Exchange (ETDEWEB)

A reconstruction of the distribution of intensity of (descending) tectonic movements for the Devonian-Permian period of the Paleozoic of the northern half of the Volga-Ural gas and petroleum province is given. A history of the paleogeothermic system with an estimation of its characteristics is for which purpose a new tchnique based on the principle of a direct relationship between the intensity of the paleotectonic and the paleothermic processes is developed. Depths of the temperature zone corresponding to GZN are given. A monotypic cyclicity of the geotectonic-geothermic cycle and depth conditions for the generation and primary migration of hydrocarbons is based on an analysis of the data obtained. A regionalization based on the intensity of the given system and the most favorable conditions for depth GZN conditions is performed. Several aspects of hydrocarbon genesis are given further clarification from consideration of the cyclicity of depth conditions for GZN; the comparatively early geological time for the formation of gas and oil deposits, especially, is confirmed. The technique for paleogeothermic reconstructions developed here is applicable in other geological situations with corrections for the established values of constants.

Maksimov, S.P.; Dobrida, E.D.

1980-01-01

58

The presence of hydrocarbons in southeast Norway  

DEFF Research Database (Denmark)

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 amphibolites, and especially in primary and secondary pores in Cambrian, Ordovician and Silurian sedimentary rocks. In some places, vesicles in Carboniferous rhomb porphyry lava (RP1), gabbro and basalt (B1) are partly cemented with pyrobitumen, together with calcite, quartz and various accessory minerals. The pyrobitumen occurs as a jet-black, brittle, amorphous, non-fluorescent substance with a specific gravity of about 1.3 g/cm3 and a conchoidal fracture. Earlier analyses have shown great similarities with regard to the stable isotopes d13C in Alum Shale (Middle Cambrian to Lower Ordovician) and pyrobitumen, 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 of the Oslo Rift. These hydrocarbons are found in tectonically disturbed Precambrian basement rocks, veins in Lower Palaeozoic sedimentary rocks and as infills in amygdales in the two oldest extrusives (RP1 and B1) known from the Oslo Graben. The first migration phase was probably mainly directed towards higher stratigraphic levels. The second migration phase is suggested to have been much more complex including lateral, vertical and even downwards migration to basement. The occurrence of pyrobitumen in basement rocks outside the Oslo Graben, where no Palaeozoic rocks have been preserved, indicates that a thick cover of Palaeozoic sediments and lavas was originally also present outside the Oslo Rift.

Hanken, Niels Martin; Hansen, Malene Dolberg

59

Carbonate redistribution, element mobilisation and petroleum hydrocarbon migration in Posidonia shale (Hils basin, NW Germany) as a function of palaeotemperature load from the Vlotho mass; Karbonatumverteilung, Mobilisation von Elementen und Migration von Erdoel-Kohlenwasserstoffen im Posidonienschiefer (Hilsmulde, NW-Deutschland) in Abhaengigkeit von der Palaeotemperaturbeanspruchung durch das Massiv von Vlotho  

Energy Technology Data Exchange (ETDEWEB)

Temperature-controlled processes of carbonate redistribution, element mobilisation and petroleum hydrocarbon migration in the Posidonia shale of North West Germany (Lower Toarcian) were documented, and a statistical evaluation was made. The investigations focused on six Posidonia shales of the Hils basin which had been exposed to increasing palaeotemperature stress from SE to NW in the direction of the injected mass of Vlotho. According to earlier investigations, the mean values of vitrinite reflection in the six boreholes are between 0.48% Rm and 1.45% Rm. This corresponds to a maximum palaeotemperature of 93-190 C. (orig./EF) [Deutsch] Im Rahmen der vorliegenden Arbeit wurden temperaturgesteuerte Prozesse der Umverteilung von Karbonaten, der Mobilisation von Elementen und der Migration von Erdoel-Kohlenwasserstoffen im nordwestdeutschen Posidonienschiefer (Unteres Toarcium) dokumentiert und bilanziert. Gegenstand der Untersuchungen waren sechs Posidonienschieferprofile aus dem Bereich der Hilsmulde, die von SE and NW in Annaeherung an das Intrusivmassiv von Vlotho eine zunehmende Palaeotemperaturbeanspruchung erfahren haben. Frueheren Untersuchungen zufolge liegen die Mittelwerte der Vitrinitreflexion in den sechs Bohrungen zwischen 0,48% Rm und 1,45% Rm, was einem Bereich der maximal erreichten Palaeotemperatur zwischen ca. 93 C und ca. 190 C entspricht. (orig./EF)

Jochum, J.

1993-04-01

60

Hydrocarbons and magnetizations in sedimentary rocks  

Energy Technology Data Exchange (ETDEWEB)

Hydrocarbons can have variable effects on the magnetic properties of sedimentary rocks. Understanding the nature of these effects has implications for dating hydrocarbon migration and magnetic prospecting. Previous work on hydrocarbon migration and magnetic prospecting. Previous work on hydrocarbon saturated calcite speleothems has established that hydrocarbons can create the chemical conditions that lead to precipitation of magnetite and acquisition of an associated chemical magnetization. The mechanism(s) of magnetite authigenesis, however, is unresolved. Geochemical studies of the speleotherms provide some information on the nature of the relationship. The level of biodegradation is variable, and samples with high magnetic intensities have, in general, lower apparent biodegradation levels than those with low magnetic intensities. These results suggest that biodegradation is not the only mechanism of magnetite precipitation. Although hydrocarbons can cause an increase in magnetization due to precipitation of magnetic phases in some rocks, in red beds there is an overall decrease in magnetization due to dissolution of hematite. For example, hydrocarbon migration into the Schoolhouse Member of the Maroon Formation (Pennsylvanian) in northwestern Colorado and the Rush Springs Formation (Permian) in Oklahoma caused dissolution of diagenetic hematite, bleaching, and a reduction in magnetic intensity. Magnetite and pyrrhotite are present in hydrocarbon-bearing sandstone and in some well cemented samples there are stable magnetizations that may be related to hydrocarbon migration.

Frutt, D.; Elmore, R.D.; Engel, M.; Imbus, S.; Leach, M. (Univ. of Oklahoma, Norman (United States))

1991-03-01

 
 
 
 
61

Petroleum hydrocarbons  

International Nuclear Information System (INIS)

[en] Methods for analysis of petroleum hydrocarbons in marine samples are presented. Types of hydrocarbons present and their origins are discussed. Principles and methods of analysis are outlined. Infrared spectrometry, uv spectrometry, gas chromatography, mass spectroscopy, and carbon 14 measurements are described

1976-01-01

62

Bird Migration  

Science.gov (United States)

The songs of spring are in the air, as northbound birds grace the skies. The following websites cover various aspects of the amazing and ancient phenomenon of bird migration. Hosted by the U.S. Geological Survey Northern Prairie Wildlife Research Center, the (1) first site is an online publication from the U.S. Fish and Wildlife Service on the Migration of Birds. This publication provides an extensive account of migration including sections on Techniques for Studying Migration, Evolution of Migration, Flight Speed and Rate of Migration, and many more. The (2) second site from birdnature.com is a webpage describing the Flyway Systems of North America accompanied by clearly labeled maps. The (3) third site from the University of Lund, Sweden introduces various research studies in the field of Migration Ecology including research information on Orientation and Navigation, Migration patterns, the Lund Wind Tunnel, and more. The (4) fourth site presents the Canadian Migration Monitoring Network, a standardized effort involving multiple stations in southern Canada and the northern United States to gather baseline data on northern breeding birds. Site visitors can link to information about species population trends, latest sightings, and to sites for any of the 22 stations. Journey North hosts the (5) fifth site, which tracks migrating bald eagles through the spring of 2004, providing migration updates, information about tracking bald eagle migration, and related educational lessons and activities. A National Geographic 2004 feature, Crane Cam is the (6) sixth site providing multimedia shows, a photo gallery, map, and viewings from a live remote camera at Audubon's Rowe Sanctuary. The (7) seventh site features an interactive Migration Game created by the Migratory Bird Center at the Smithsonian National Zoological Park. The (8) final site, from the Whyfiles contains brief sections on various aspects of bird migration such as navigation, flight strategies, raptor migration, and declining numbers of migrating songbirds. This site also links to information about monarch migration.

63

Ictericia obstructiva secundaria a migración de fragmentos de hepatocarcinoma a la vía biliar Obstructive jaundice secondary to hepatocellular carcinoma fragments migrated to common bile duct  

Directory of Open Access Journals (Sweden)

Full Text Available La ictericia obstructiva es una presentación poco común en un hepatocarcinoma (HC). Cuando en estos casos existe ictericia, habitualmente se debe a daño progresivo por cirrosis, o a infiltración tumoral extensa. El crecimiento o vaciamiento tumoral hacia la vía biliar se ha descrito ocasionalmente como causa de ictericia obstructiva. En raras ocasiones, puede tratarse de fragmentos de hepatocarcinoma que migran hacia la vía biliar, obstruyéndola. Presentamos un caso de ictericia obstructiva por migración de fragmentos de hepatocarcinoma a la vía biliar, en un paciente tratado 7 años antes por un HC, con resección curativa.Obstructive j aundice is a rare presentation of hepatocellular carcinoma (HC), and when it occurs, usually is due to progressive damage from cirrhosis, or extensive tumor infiltration. Tumor growth through the bile duct is being described with increasing frequency as a cause of obstructive j aundice. Rarely, it may be hepatocarcinoma fragments that migrate to the bile duct, obstructing it. We present a case of obstructive jaundice due to migration of fragments of hepatocellular carcinoma to the bile duct in a patient treated 7 years before, for an HC with a curative resection.

JUAN HEPP K; PAULINA BALBONTÍN M; RODOLFO ARMAS M; CLAUDIO NAVARRETE G; HORACIO RÍOS R; ROBERTO HUMERES A; GABRIELA RODRÍGUEZ M; IVÁN ROA E

2010-01-01

64

Formation conditions of hydrocarbon formations  

Energy Technology Data Exchange (ETDEWEB)

The weakest link in the plan of forming oil formations is questions of hydrocarbon emigration from oil source rocks and their further migration to the sites of accumulation. Results are presented from laboratory experiment to reveal naphthenic acids and their soaps (surfactants) on solubility of hydrocarbons in water saturated and not saturated with natural gas. The experiments were conducted in the example of individual hydrocarbon, toluene, distilled water and alkaline aqueous solutions of a mixture of naphthenic acids, slightly concentrated solutions of soap (sodium oleate), rock (chalk marl) with water saturation by carbon dioxide and with its absence. According to experimental data, the system of formations can be developed according to the plan of hydrocarbon transfer by bed waters containing soap of fatty and naphthenic acids, and saturated with natural gases. In the zones of hydrocarbon generation in the source mass in the alkaline medium, fairly energetic desolving in water of liquid and gaseous hydrocarbons, as well as CO/sub 2/ in the presence of salts of organic acids occurs. At the same time calcium bicarbonates become carbonates in sediment. Decrease in the solution in the content of calcium bicarbonates results in a decrease of solubility of salts and fatty acids, and correspondingly salting out of the liquid hydrocarbons, already in elevated collector masses.

Yeremenko, N.A.; Safronova, T.P.; Sergeyevich, V.I.

1981-01-01

65

Hydrocarbon transfer pathways from Smackover source rocks to younger reservoir traps in the Monroe gas field, NE Louisiana  

Energy Technology Data Exchange (ETDEWEB)

The Monroe gas field contained more than 7 tcf of gas in its virgin state. Much of the original gas reserves have been produced through wells penetrating the Upper Cretaceous Monroe Gas Rock Formation reservoir. Other secondary reservoirs in the field area are Eocene Wilcox, the Upper Cretaceous Arkadelphia, Nacatoch, Ozan, Lower Cretaceous, Hosston, Jurassic Schuler, and Smackover. As producing zones, these secondary producing zones reservoirs have contributed an insignificant amount gas to the field. The source of much of this gas appears to have been in the lower part of the Jurassic Smackover Formation. Maturation and migration of the hydrocarbons from a Smackover source into Upper Cretaceous traps was enhanced and helped by igneous activity, and wrench faults/unconformity conduits, respectively. are present in the pre-Paleocene section. Hydrocarbon transfer pathways appear to be more vertically direct in the Jurassic and Lower Cretaceous section than the complex pattern present in the Upper Cretaceous section.

Zimmerman, R.K. (Louisiana State Univ., Baton Rouge, LA (United States))

1993-09-01

66

MIGRATION AND ITS ENVIROMENTAL EFFECTS  

Directory of Open Access Journals (Sweden)

Full Text Available 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 with this area to date, and the research is supposed like an intensifying method of the actual evaluation from the environment sizing associated with migration.

Rashid SAEED; Rana NADIR IDREES; Humna IJAZ; Marriam FURQANI; Raziya NADEEM

2012-01-01

67

Method for producing viscous hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

A method for recovering viscous hydrocarbons and synthetic fuels from a subterranean formation by drilling a well bore through the formation and completing the well by cementing a casing means in the upper part of the pay zone. The well is completed as an open hole completion and a superheated thermal vapor stream comprised of steam and combustion gases is injected into the lower part of the pay zone. The combustion gases migrate to the top of the pay zone and form a gas cap which provides formation pressure to produce the viscous hydrocarbons and synthetic fuels.

Poston, Robert S. (Winter Park, FL)

1982-01-01

68

Hydrocarbons Act  

Energy Technology Data Exchange (ETDEWEB)

Exploration research and mining of hydrocarbons, regulation of the petroleum by-products market, regulation of the supply of fuel gases through pipeline, entitlement to occupy the public domain, compulsory purchase orders, land requirements and limitations on ownership.

NONE

2002-07-01

69

International Migration  

Science.gov (United States)

This Website, Push and Pull Factors of International Migration, features background and preliminary research data from a joint project of Eurostat and The Netherlands Interdisciplinary Demographic Institute the goal of which is to "improve understanding of the direct and indirect causes and mechanisms of international migration to the European Union from an internationally comparative perspective. The project is an effort to respond to the fact that "international migration flows have increased in magnitude and complexity over the past decades." Separate sections of the site provide information on the aim, objectives, and approach of the project; the research design; as well as a summary of first results on recent migration, migration motives, migration networks, and migration intentions; and further bibliographic and Web-based resources. The project is under the auspices of the Commission of the European Communities.

70

Bird Migration  

Science.gov (United States)

The first Web site (1) from Sony Picture Classics presents the official home page for "Winged Migration," the new, Academy-award nominated documentary from director Jacques Perrin that follows the epic migrations of birds worldwide using innovative techniques to capture amazing migration footage. Visitors to this site will find a trailer for the film, bird watching Web links, production notes, information on related environmental issues, and a very cool interactive feature showing bird migration routes. Not surprisingly, the Migratory Bird Center at the Smithsonian National Zoological Park offers a mountain of information on bird migration, including a Bird of the Month page (2). BirdSource, a partnership of the National Audubon Society and the Cornell Lab of Ornithology, offers this online introduction to bird migration (3), including an interactive map and case studies representing the different categories of bird movement. The next Web site is the home page for the International Center for the Study of Bird Migration located in Israel, a country on the flight path of approximately 500 million migrating birds (4). The Center offers a number of real time information features, including data from satellite transmitters, nest cameras, and more. Be warned: the birdcalls that randomly emanate from your computer speakers with this Web site are kind of spooky. The BBC Science Shack, part of Open University, provides the following Web page (5), offering a brief explanation of how migrating birds know where to go. The next Web site is part of the Web companion to the PBS NOVA documentary "Night Creatures of the Kalahari." Visitors will find an interesting account of nighttime bird migration based on the research of Cornell ornithologist Bill Evans (6). The site also includes audio clips of eleven migrating bird species. Next comes the Web site for Operation Migration, the nonprofit organization famous for pioneering the use of ultra-light aircraft to teach whooping cranes a safe migration route (7). Visitors can track the progress of the latest group of cranes, who have recently left their winter habitat to make their way back to Wisconsin. And finally, visitors can find some of the best places to watch birds, migrating or otherwise, at this straightforward Web site from Birder.com (8).

Sohmer, Rachel.

2003-01-01

71

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.

1997-01-01

72

Transport of petroleum hydrocarbons in permafrost soils  

Energy Technology Data Exchange (ETDEWEB)

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.

Nahir, M. [Public Works and Government Services Canada, Environmental Services, Edmonton, AB (Canada); Biggar, K. W. M. [Alberta Univ., Edmonton, AB (Canada). Dept. of Civil Engineering

1997-12-31

73

Apparatus for hydrocarbon extraction  

Energy Technology Data Exchange (ETDEWEB)

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.

Bohnert, George W.; Verhulst, Galen G.

2013-03-19

74

Formation of secondary uranium minerals in the Koongarra deposit, Australia  

International Nuclear Information System (INIS)

Secondary uranium minerals from the Koongarra deposit, Northern Territory of Australia, were examined in order to understand the formation and alteration processes of the uranium minerals and their relevance to the migration behavior of uranium, lead, calcium and rare earth elements in the weathered zone. In most of the secondary ore zone, the only stable uranium mineral was saleeite (Mg(UO2)2(PO4)2?10H2O), occurring as euhedral platy crystals up to 1 mm in length in veins and at surfaces. Apatite (Ca5(PO4)3F), an accessory mineral of the host rock, has saleeite reaction rims, suggesting formation at the expense of apatite. Ca-uranyl phosphates, such as autunite (Ca(UO2)2(PO4)2?lOH20), were not identified, and Ca-rich uranyl silicates are also absent in the primary ore zone. Pb-bearing uranyl phosphates were found only in the graphite layer cross-cutting the secondary ore zone. In the graphite layer, the local low oxidation condition and high hydrocarbonate content of ground water have affected the formation of uranium minerals and the migration behavior of uranium.

1993-12-03

75

The Niger Delta Complex Basin: stratigraphy, structure and hydrocarbon potential  

Energy Technology Data Exchange (ETDEWEB)

The Agbada Formation is the major oil-producing formation in the Niger Delta Complex Basin, and overlies the Eocene Akata Formation, which is the principal hydrocarbon source rock. The Basin is deformed by large synsedimentary faults, roll-over anticlines and diapirs: hydrocarbon accumulations are largely controlled by growth faults. A review of the influence of the stratigraphic and structural features on the migration and accumulation of hydrocarbons is given in this paper. (author)

Chukwu, G.A. (Port Harcourt Univ. (Nigeria). Dept. of Petroleum Engineering)

1991-04-01

76

Migration Ecology  

Science.gov (United States)

This site from the University of Lund, Sweden, introduces various research studies in the field of Migration Ecology including research information on "Orientation and navigation," "Flight," "Migration patterns," and "Energetics." The mission of the group is "to forward, by research and teaching, the understanding of adaptive values and evolutionary possibilities and limitations in animal migration, -flight, -orientation and energetics." Many of the group's publications are available for free as PDFs, and the site offers a simple search mechanism to help visitors find the publications they are seeking.

Alerstam, Thomas

2008-01-15

77

Operation Migration  

Science.gov (United States)

Operation Migration, a nonprofit conservation organization dedicated to teaching safe migratory routes to endangered and threatened birds, was co-founded by William Lishman -- the pilot who pioneered the use of ultralight aircraft to lead birds in flight. Operation Migration is part of a consortium created to safeguard the endangered Whooping crane against extinction. Visitors to this Web site can track the progress of seven ultralight-led Whooping cranes now making their way from Wisconsin to Florida for the winter. The Web site provides daily field reports of the migration, a map charting the progress of the flock, loads of photos, crane biographies, video clips, and more. The site also relates the engaging story of how Operation Migration got started, one that should sound familiar to those who've seen the feature film Fly Away Home.

78

Hydrocarbon production  

Energy Technology Data Exchange (ETDEWEB)

This patent describes the process for the production of higher hydrocarbons from methane. It comprises reacting a methane containing feed gas by oxidative coupling to form a first product mixture comprises of 1.0-50 mol % CO, 1.0-50 mol % H/sub 2/, 0-50 mol % steam, 1.0-50 mol % C/sub 2/=, and 5.0-80 mol % methane, reacting the first product mixture in a second reaction over a catalyst comprised of both a metal oxide component effective for the reaction of hydrogen and carbon monoxide, and a shape selective zeolite component effective for the oligomerization of ethylene, and recovering higher hydrocarbons from the product of the second reaction.

Gaffney, A.M.

1989-07-18

79

Hydrocarbon modelling  

Energy Technology Data Exchange (ETDEWEB)

The reliability of hydrocarbon modelling methods is a major problem due to uncertain data and parameter values. The usual procedures for inversion and variance analysis are complicated by the large calculational times of numerical basin models. Approximate methods for inversion and variance analysis, which can be applied in 1-, 2-, and 3-D basin models, have been developed for the case of thermal and maturity modelling. (au)

Nielsen, S.B. [Univ. of Aarhus, Dept. of Earth Sciences (Denmark)

1998-08-01

80

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.)

1992-01-01

 
 
 
 
81

Hydrocarbon distribution in the Maracaibo Basin  

Energy Technology Data Exchange (ETDEWEB)

The prolific Maracaibo basin contains the second largest hydrocarbon accumulation in South America; it has been one of the principal oil producers of the world since the beginning of this century. Exploratory efforts in this basin, carried out with new techniques and new ideas, continue today, so it is of interest to determine the trends of hydrocarbon concentrations in terms of resources per unit volume of sediments and to correlate them to stratigraphic, sedimentary-tectonic and geochemical variables. Regional scale maps representing the 24 principal geologic and geochemical variables that are thought to be a function of hydrocarbon generation, migration and accumulation were discretized on a 25 x 25 km grid. Variables used are isopach and Total Organic Carbon (TOC) of source rocks, isopach, sandstone content and grain size parameters of reservoir rocks, isopach of stratigraphic seal and overburden, maximum paleotemperatures (R{sub o} and T{sub max}), tectonic energy (fault length and displacement) and hydrocarbon families. Multivariate analytical statistics was used to obtain the trends of hydrocarbon distributions. The resulting hydrocarbon concentration trend map was quantitatively correlated to known hydrocarbon accumulations and prospective areas, where additional new accumulations might be found, were obtained. It can be shown that the largest known hydrocarbon concentrations correspond to areas of greatest cumulative overburden. The southern Zulia Catatumbo region is the largest prospective area determined by this method.

Scherer, W. [Intevep, Los Teques (Venezuela)

1996-08-01

82

High-temperature dolomites in the Ordovician section of Anticosti Island, Eastern Canada : implications for hydrocarbon reservoirs development  

Energy Technology Data Exchange (ETDEWEB)

The hydrocarbon reservoirs in the Ordovician carbonates along the continental margin of Laurentia were formed by dolomitization caused by circulating hydrothermal fluids. A study of the Ordovician succession on Anticosti Island has shown late hydrocarbon migration and multiple events of dolomitization at the peritidal facies of the Lower Ordovician Romaine Formation. A late hydrothermal event was responsible for high porosities resulting from highly saline fluids (24 wt per cent NaCl). Portions of fractures in zones with low permeabilities were filled with a later hydrocarbon inclusion-rich calcite. Three dolomitization events are recorded for the open marine limestones of the Middle-Upper Ordovician Mingan Formation. Dolomite replacement was observed only in pore-filling calcite. The latest dolomite replacement occurred under high temperature conditions with highly saline fluid inclusions. The hydrothermal fluids were circulated in the Romaine aquifer and breached into the Mingan at the edge of the Lower Ordovician platform in northern Anticosti. The Middle-Upper Ordovician Mingan Formation was altered by the fluids circulating along major extensional faults. Gas shows from the Mingan interval in southern Anticosti wells suggest that the fluids grew colder as the migrated upwards, generating secondary porosity.

Lavoie, D. [Geological Survey of Canada - Quebec Division, Ste-Foy, PQ (Canada); Chi, G. [Regina Univ., SK (Canada)

2003-07-01

83

Monarch Migration.  

Science.gov (United States)

|Describes the Monarch Watch program that tracks the migration of the monarch butterfly. Presents activities that introduce students to research and international collaboration between students and researchers. Familiarizes students with monarchs, stimulates their interest, and helps them generate questions that can lead to good research projects.…

Williamson, Brad; Taylor, Orley

1996-01-01

84

Migration & Modernity  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The main objective of this essay is to analyze the challenges caused by today's modern phenomenon of change in our society and to discuss it in relationship to the process of migration. In doing so I focus on questions like, "what does it really mean when a person becomes a migrant and what does it ...

Budathoki, Aakash

85

Neuronal Migration Disorders  

Science.gov (United States)

NINDS Neuronal Migration Disorders Information Page Table of Contents (click to jump to sections) What is Neuronal Migration Disorders? Is there ... being done? Clinical Trials Organizations What is Neuronal Migration Disorders? Neuronal migration disorders (NMDs) are a group ...

86

Hydrocarbon conversion process  

Energy Technology Data Exchange (ETDEWEB)

A hydrocarbon conversion process is disclosed having a very high selectivity for dehydrocyclization. In one aspect of this process, a hydrocarbon feed is subjected to hydrotreating, then the hydrocarbon feed is passed through a sulfur removal system which reduces the sulfur concentration of the hydrocarbon feed to below 500 ppb, and then the hydrocarbon feed is reformed over a dehydrocyclization catalyst comprising a large pore zeolite containing at least one Group VIII metal to produce aromatics and hydrogen.

Buss, W.C.; Field, L.A.; Robinson, R.C.

1984-06-26

87

Direct Radiometric Dating of Hydrocarbon Deposits Using Rhenium-Osmium Isotopes  

Science.gov (United States)

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.

Selby, David; Creaser, Robert A.

2005-05-01

88

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

UK PubMed Central (United Kingdom)

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.

Selby D; Creaser RA

2005-05-01

89

A kinetically controlled fluid pressure and migration model  

Energy Technology Data Exchange (ETDEWEB)

New concepts of silicate diagenesis and their effects on rock properties have major implications for predictive models of geopressure and migration scale/efficiency. At temperatures greater than approximately 70{degrees}C, precipitation rate controlled internally sourced quartz cementation and neoformation of diagenetic clay become important porosity and permeability reduction factors, respectively. In shales, clay diagenesis rapidly reduces permeability, rendering them prone to overpressure. The shale/source rock capillary pressure is increased dramatically and later onset of hydrocarbon expulsion is facilitated by microfractures, which allows for greatly increased expulsion and lateral primary migration efficiency. Quartz cementational porosity loss in sandstones and millstones proceeds mainly independent of pressure and hydrocarbon saturation, which can result in hydrofracturing of the overlying seals/shales. The affect of hydrofracturing results in a coupling of thermally controlled porosity reduction processes, fluid overpressure, and episodic expulsion. In areas of thick shales, the probability of long range, km scale, vertical migration increases such that hydrocarbon migration to shallower sequences increases. Correspondingly, the preservation of economically attractive hydrocarbon accumulations at depth is reduced, except in reservoirs with mitigating geologic factors. The underlying thermal controls of silicate diagenetic and organic maturation processes result in {open_quote}self-organized{close_quote} basin scale fluid migration systems which optimizes the occurrence of economic hydrocarbon accumulations to certain stratigraphic/structural levels within any given basin.

Bjorkum, P.A.; Nadeau, P.H. [Statoil (Norway)

1996-12-31

90

Cross-Border Migration and East Asian Regional Integration  

Directory of Open Access Journals (Sweden)

Full Text Available Against the background of profound economic and political changesin East Asia, this paper examines key trends in migration within theregion. It highlights the increasingly multidirectional nature ofmigration flows, the importance of undocumented migration, and thegrowing significance of secondary diasporas and return migration.While future large-scale flows of migration are likely, the changingnature of regional migration makes it more difficult for existinginternational frameworks to respond adequately to these cross-borderflows. Against this background, the paper argues the need to developnew regional collaborative mechanisms, involving national and localgovernments as well as national and international NGOs, to respondto the challenges of East Asian migrations.

Tessa Morris Suzuki

2007-01-01

91

Hydrocarbon Formation in Immature Sediments  

Directory of Open Access Journals (Sweden)

Full Text Available Immature sediments (Ro=<0.6) and hydrates commonly contain low concentrations of C2-8+ alkanes/alkenes, higher alkanes, cycloalkanes and aromatics (temperature=<373 K; Pressure=<100 MPa). Their origin is enigmatic. Traditionally they are interpreted as migrated thermogenic oil. Water treatment experiments have established that they could be formed through the interaction of water and organic carbon by Fe catalysis at 298 K. This study investigates the Eh and pH associated with low temperature (263-298 K) hydrocarbon formation in saline pore-waters containing Ca-montmorillonite and Fe0 (ZVI) over a 300 day period in order to identify the principal reaction mechanisms. The interaction of flowing gaseous carbon dioxide-hydrocarbon mixtures with halite promoted with FexOy, Fex[OH]y at 288 – 308 K is examined experimentally. The study established that halite and mixtures of halite with organic material, Fe-montmorillonite, CaCO3, Ca(OH)2, MgSO4, (NH4)2SO4, K2SO4, pyroclastics, ash, phosphate enriched organic material, and coal can facilitate the removal of CO2, the formation of H2O on the catalyst surface, and the formation of hydrocarbons incorporating the CO2.Key Word: ZVI; Oil formation; CO2; Eh; pH; NaCl; Halite; Montmorillonite

D.D.J. ANTIA

2011-01-01

92

Miracle of Winged Migration  

Science.gov (United States)

This site, from the Why Files contains brief sections on various aspects of bird migration such as navigation, flight strategies, raptor migration, and declining numbers of migrating songbirds. This site also links to information about monarch migration and the effects of global warming on migration of birds and butterflies alike.

Tenenbaum, David

2007-12-31

93

Migration of Birds  

Science.gov (United States)

Hosted by the U.S. Geological Survey Northern Prairie Wildlife Research Center, this site is an online publication from the U.S. Fish and Wildlife Service on the Migration of Birds. This publication provides an extensive account of migration including sections on Techniques for Studying Migration, Evolution of Migration, Flight Speed and Rate of Migration, and many more.

Lincoln, Frederick C.; Peterson, Steven R.; Zimmerman, John L.

2008-01-03

94

Hydrocarbon fuel composition  

Energy Technology Data Exchange (ETDEWEB)

A fuel composition having enhanced tolerance for water comprises a hydrocarbon base fuel, a polyether more soluble in the hydrocarbon base fuel than in water, and, optionally, a supplemental fuel component such as, for example, an alcohol.

Parkinson, H.B.

1983-10-18

95

Process for producing hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

A process is described for producing a hydrocarbon product consisting essentially of hydrocarbons having about 10 to 50 carbon atoms with 60% or more of said product consisting of hydrocarbons containing 25 to 32 carbon atoms which comprises subjecting a synthetic polyisoprene rubber having 92 to 97% cis-type double bods to a thermally destructive distillation at about 300 to 400/sup 0/ C for about 30 minutes under a reduced pressure of about 0.1 to 5 mm. Hg to obtain said hydrocarbon product consisting essentially of hydrocarbons having about 10 to 50 carbon atoms with 60% or more of said product consisting of hydrocarbons containing 25 to 35 carbon atoms, said hydrocarbon product not having a bad odor and containing scarcely any resinous material.

Doi, K.; Komatsu, A.; Moroe, M.; Moroe, T.

1980-07-22

96

Secondary liposarcoma of the ovary.  

UK PubMed Central (United Kingdom)

This report is the first description of a secondary ovarian liposarcoma. The primary growth was in the mediastinum. The growth rate of the ovarian tumor was very rapid, but the patient died of cardiopulmonary causes. The mode of spread is discussed, and it probably occurred by transcelomic migration and surface implantation.

Rodeck CH; Pryse-Davies J; Malvern J; Morgan RL; Bennett G

1977-01-01

97

Formation of hydrocarbon deposits of the eastern part of Karpinskiy swell  

Energy Technology Data Exchange (ETDEWEB)

Based on the helium content in hydrocarbon gases and its ratio to methane and methane homologs, hydrocarbons migratory paths are examined. With all possible types of hydrocarbon gas migration, the latter will be enriched by helium. In the ratio of helium to methane and methane homologs, three groups of fields are isolated. The isolated groups differs from each other by their content of methane, methane homologs, helium and the interrelationship of helium with hydrocarbons. A plan is proposed for the formation of these fields. The gas fields of the Promyslovo-Tsubukskiy zone of elevations was formed because of hydrocarbons which entered from the southeast territory. The first structure located on the migratory pathy of hydrocarbons was the Promyslovskiy. In the Caspian-Kamyshinskiy zone of elevations, the hydrocarbons entered on two migratory hydrocarbon paths. Fields in the eastern part of the Karpinskiy swell were formed as a result of jet and water-dissolved mirgration of hydrocarbons. In the PromyslovoTsubukskiy zone of elevations, the first structures on the hydrocarbon migratory path filled them with light fractions. Heavier fractions were sorbed by rocks on the migratory path. Later, hydrocarbons entered with heavier fractions and they filled the subsequent structures. In the Caspian-Kamyshanskiy zone of elevations, hydrocarbon distribution occurred according to the principle of differential hydrocarbon trapping where the first traps on the migratory path accumulated gas, while oil was displaced higher through the increase in beds.

Sbitnev, V.M.

1980-01-01

98

Aux Vases Sandstone diagenesis: Implications for hydrocarbon recovery from southern Illinois reservoirs  

Energy Technology Data Exchange (ETDEWEB)

The Aux Vases Sandstone (Mississippian) is a problematic yet productive reservoir in the Illinois basin. The Aux Vases Formation was deposited in a mixed siliciclastic-carbonate offshore environment. Hydrocarbon reservoirs are dominantly elongate sandstone bodies interpreted as subtidal facies within a prograding tidally influenced deposystem. Oil saturated zones, in most cases, are composed of fine-grained, cross-bedded, friable, feldspathic quartz sandstone. Resistivity logs, even from productive wells, are typically characterized by unusually low resistivities (2-4 ohms) that lead to high calculated water saturations. X-ray diffraction, SEM/EDS, and thin section studies were used to analyze diagenetic processes that may affect hydrocarbon production in several Aux Vases reservoirs. Diagenetic processes common to the field studied include: (1) early calcite cementation occluding primary porosity and inhibiting compaction, (2) dissolution of feldspar grains to form authigenic clay, (3) dissolution of early calcite cement, (4) diagenesis of detrital clay minerals into new authigenic clay minerals, and (5) multiple stages of quartz overgrowths that reduce porosity. Commonly used drilling and completion practices may adversely affect reservoir quality by reacting with diagenetic products. Loosening of the fine mineral fraction that causes migration of fines and swelling of expandable clay minerals are examples of this type of damage. Knowledge of reservoir mineralogy and diagenesis may influence drilling and completion practices and affect selection of secondary and tertiary recovery methods.

Seyler, B.D.; Beaty, D.S.; Huff, B.G. (Illinois State Geological Survey, Champaign (United States))

1991-03-01

99

AROMATIC HYDROCARBON PRODUCTION PROCESS  

UK PubMed Central (United Kingdom)

This aromatic hydrocarbon production process comprises bringing a raw material oil which contains a hydrogenated oil product of a thermally cracked heavy oil produced in an ethylene production apparatus into contact with a monocyclic aromatic hydrocarbon production catalyst which contains a crystalline aluminosilicate to produce an aromatic hydrocarbon. The raw material oil to be used has a distillation end point temperature of 400 DEG C or lower. The contact between the raw material oil and the monocyclic aromatic hydrocarbon production catalyst is carried out under a pressure of 0.1 to 1.5 MPaG.

YANAGAWA SHINICHIRO; IDA RYOJI; KOBAYASHI MASAHIDE

100

Hydrocarbon Reserves: Abundance or Scarcity  

International Nuclear Information System (INIS)

[en] 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)

2005-01-01

 
 
 
 
101

Membrane separation of hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

A process is described for the separation of a deasphalted crude oil and a light hydrocarbon solvent from a mixture thereof which comprises passing the mixture over a membrane. The membrane comprises polysulfone at separation conditions whereby the light hydrocarbon solvent is recovered as the permeate and the deasphalted crude oil is recovered as the retentate.

Funk, E.W.; Kulkarni, S.S.; Chang, Y.A.

1986-10-14

102

Hydrocarbon fuels from biomass  

Energy Technology Data Exchange (ETDEWEB)

With a view to developing petro-crops as a source of hydrocarbon fuels, indigeneous laticiferous species belonging to the families Euphorbiaceae, Asclepiadaceae and Convolvulaceae have been evaluated for their biocrude potential. Hydrocracking of biocrude, from E. royleana, E. neriifolia, Cryptostegia grandiflora and Calotropis gigantea to hydrocarbon fuels, preferably middle distillates, has been demonstrated. 26 refs., 6 tabs.

Bhatia, V.K.; Mittal, K.G.; Mehrotra, R.P.; Mehrotra, M.

1989-04-01

103

Polycyclic antiaromatic hydrocarbons.  

Science.gov (United States)

Magnetically induced current densities have been calculated for a series of hydrocarbons consisting of hexadehydro[12]annulene rings alternatingly fused with benzenes. The calculations show that all molecular rings of the studied molecules sustain paramagnetic ring currents. The new class of molecules is therefore coined polycyclic antiaromatic hydrocarbons (PAAH). PMID:18989474

Jusélius, Jonas; Sundholm, Dage

2008-09-25

104

Plant hydrocarbon recovery process  

Energy Technology Data Exchange (ETDEWEB)

A process for production and recovery of hydrocarbons from hydrocarbon-containing whole plants in a form suitable for use as chemical feedstocks or as hydrocarbon energy sources which process comprises: (A) pulverizing by grinding or chopping hydrocarbon-containing whole plants selected from the group consisting of euphorbiaceae, apocynaceae, asclepiadaceae, compositae, cactaceae and pinaceae families to a suitable particle size, (B) drying and preheating said particles in a reducing atmosphere under positive pressure (C) passing said particles through a thermal conversion zone containing a reducing atmosphere and with a residence time of 1 second to about 30 minutes at a temperature within the range of from about 200* C. To about 1000* C., (D) separately recovering the condensable vapors as liquids and the noncondensable gases in a condition suitable for use as chemical feedstocks or as hydrocarbon fuels.

Dzadzic, P.M.; Price, M.C.; Shih, C.J.; Weil, T.A.

1982-01-26

105

Migration and revolution  

Directory of Open Access Journals (Sweden)

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.

Hein de Haas; Nando Sigona

2012-01-01

106

Macroeconomic influences on migration.  

UK PubMed Central (United Kingdom)

"The changing composition and magnitude of internal migration flows are of critical importance in determining the potential economic growth of a region. Yet, there can be little doubt that the business cycle has a significant influence on migration flows and propensities. This paper explores the effects of macroeconomic events on migration [within Canada] through an examination of the extent of the influence of the national and regional business cycle on the in-, out- and net-migration rates." (SUMMARY IN FRE AND GER)

Milne WJ

1993-01-01

107

Dimensions in cell migration.  

UK PubMed Central (United Kingdom)

The importance of cell migration for both normal physiological functions and disease processes has been clear for the past 50 years. Although investigations of two-dimensional (2D) migration in regular tissue culture have elucidated many important molecular mechanisms, recent evidence suggests that cell migration depends profoundly on the dimensionality of the extracellular matrix (ECM). Here we review a number of evolving concepts revealed when cell migration is examined in different dimensions.

Doyle AD; Petrie RJ; Kutys ML; Yamada KM

2013-10-01

108

Dimensions in cell migration.  

Science.gov (United States)

The importance of cell migration for both normal physiological functions and disease processes has been clear for the past 50 years. Although investigations of two-dimensional (2D) migration in regular tissue culture have elucidated many important molecular mechanisms, recent evidence suggests that cell migration depends profoundly on the dimensionality of the extracellular matrix (ECM). Here we review a number of evolving concepts revealed when cell migration is examined in different dimensions. PMID:23850350

Doyle, Andrew D; Petrie, Ryan J; Kutys, Matthew L; Yamada, Kenneth M

2013-07-10

109

Diagenesis of deeply buried Eagle Mills sandstones. Implications for paleo-fluid migration and porosity development  

Energy Technology Data Exchange (ETDEWEB)

Eagle Mills strata (Triassic-Jurassic) unconformably overlie the Paleozoic basement complex and thus, form the basal sedimentary unit within the Gulf Coast basin. Jurassic-aged basaltic dikes and sills have intruded Eagle Mills strata. These sedimentary and igneous rocks are the earliest record of Gulf of Mexico rifting. Deeply buried (15,000 to 18,000 ft.) Eagle Mills sandstone have subarkosic and sublithic modal compositions. These sandstones exhibit evidence of a complex and prolonged diagnetic history, including: early chlorite cementation; early quartz and feldspar overgrowths; early calcite and dolomite cementation; dissolution of framework grains and early carbonate cements; kaolinite precipitation; late ferroan carbonate cementation; albitization; late chlorite and anhydrite replacement; saddle dolomite cementation; and pyritization. Pyrobitumens coat early chlorite rim cements indicating that most diagenesis post-dated hydrocarbon migration. Secondary porosity development coincided with a later burial dissolution event. The Eagle Mills paragenetic sequence records progressive burial into a high-temperature diagenetic regime where thermochemical sulfate reduction was the dominant process. Marked shifts in paleo-water chemistry are recorded by the Eagle Mills diagenetic sequence. Pervasive dissolution of detrital feldspars in some Eagle Mills sandstones provides unequivocal petrographic evidence for deep-seated sourcing of diagenetic fluids, which migrated along faults, and contributed to the diagenesis of overlying Mesozoic strata. These petrographic analyses support interpretations of geochemical/fluid-flux data for the Mesozoic Gulf Coast basin.

Dawson, W.C. [Texaco EPTD, Houston, TX (United States)

1995-10-01

110

Migration and Adult Education  

Science.gov (United States)

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…

Gois, William

2007-01-01

111

Sequential cracking of hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

A process is described for the production of ethylene from the pyrolytic cracking of a hydrocarbon consisting essentially of ethane in a pyrolytic cracking furnace having disposed therein a plurality of elongated serpentine-situated thermal cracking tubes. The process consists of: (a) passing a first hydrocarbon feed material having a carbon atom content of greater than 2 through the plurality of elongated serpentine-situated thermal cracking tubes to crack the first hydrocarbon at cracking conditions effective to produce a first hydrocarbon product and coke, wherein the cracking conditions and throughput of the first hydrocarbon is sufficient to selectively place an amorphous relatively smooth coat of coke on the interior of the plurality of elongated serpentine-situated thermal cracking tubes, wherein the coat of coke is of thickness of about between about 1/16 inch and about 1/8 inch; (b) stopping the passage of the first hydrocarbon feed material through the thermal cracking tubes; and (c) passing a second hydrocarbon consisting essentially of the ethane through the plurality of elongated serpentine-situated thermal cracking tubes having the cost of amorphous relatively smooth coat of coke theron at ethane cracking conditions to crack the ethane to ethylene, which is recovered from the pyrolytic cracking furnace.

Buddell, R.L.; Oswald, A.M.; Lagarde, W.A.

1986-07-08

112

Plasma Processing Of Hydrocarbon  

Energy Technology Data Exchange (ETDEWEB)

The Idaho National Laboratory (INL) developed several patented plasma technologies for hydrocarbon processing. The INL patents include nonthermal and thermal plasma technologies for direct natural gas to liquid conversion, upgrading low value heavy oil to synthetic light crude, and to convert refinery bottom heavy streams directly to transportation fuel products. Proof of concepts has been demonstrated with bench scale plasma processes and systems to convert heavy and light hydrocarbons to higher market value products. This paper provides an overview of three selected INL patented plasma technologies for hydrocarbon conversion or upgrade.

Grandy, Jon D; Peter C. Kong; Brent A. Detering; Larry D. Zuck

2007-05-01

113

PROCESS FOR PREPARING HYDROCARBONS  

UK PubMed Central (United Kingdom)

A process for preparing a hydrocarbon or mixture of hydrocarbons comprising the steps of (i) hydrogenating furfural, 5-hydroxymethylfurfural or a mixture of furfural and 5-hydroxymethylfurfural to provide furfuryl alcohol, 2, 5-furandimethanol or a mixture of furfuryl alcohol and 2, 5-furandimethanol (ii) oligomerizing the alcohol or mixture of alcohols of step (i) in the presence of an acidic catalyst to provide a carbon-carbon coupled oligomer and (iii) hydrogenating the oligomer of step (ii) is provided. The hydrocarbons are useful as fuel blending components. Processes for controlling the oligomerization of alcohol or mixture of alcohols to optimise the production of oligomers suitable for conversion to hydrocarbons useful as kerosene and diesel components are also provided.

VAN BUIJTENEN JEROEN; LANGE JEAN-PAUL; PRICE RICHARD JOHN

114

Hydrocarbon recovery from diatomite  

Energy Technology Data Exchange (ETDEWEB)

Supercritical extraction of diatomaceous earth results in a much more significant improvement in hydrocarbon recovery over Fischer retorting than achievable with tar sands. Process and apparatus for supercritical extraction of diatomaceous earth are disclosed.

Scinta, J.

1984-05-15

115

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

1993-12-02

116

Hydrocarbon geoscience research strategy  

Energy Technology Data Exchange (ETDEWEB)

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.

1990-04-01

117

Membrane separation of hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

Mixtures of heavy oils and light hydrocarbons may be separated by passing the mixture over a polymeric membrane which comprises a polymer capable of maintaining its integrity in the presence of hydrocarbon compounds at temperature ranging from about ambient to about 100.degree. C. and pressures ranging from about 50 to about 1000 psi. The membranes which possess pore sizes ranging from about 10 to about 500 Angstroms are cast from a solvent solution and recovered.

Funk, Edward W. (Highland Park, IL); Kulkarni, Sudhir S. (Hoffman Estates, IL); Chang, Y. Alice (Des Plaines, IL)

1986-01-01

118

The geology and evolution of the South Pepper hydrocarbon accumulation  

Energy Technology Data Exchange (ETDEWEB)

The South Pepper field, discovered in 1982, is located 30 km southwest of Barrow Island in the offshore portion of the Barrow Sub-basin, Western Australia. The oil and gas accumulation occurs in the uppermost sands of the Lower Cretaceous Barrow Group and the overlying low permeability Mardie Greensand Member of the Muderong Shale. The hydrocarbons are trapped in one of several fault closed anticlines which lie on a high trend that includes the North Herald, Pepper and Barrow Island structures. Geochemical and structural evidence indicates at least two periods of hydrocarbon migration into the top Barrow Group - Mardie Greensand reservoir. The earlier occurred in the Turonian subsequent to the period of wrench tectonics and involved the migration of oil from Lower Jurassic Dingo Claystone source rocks up the South Pepper Fault. This oil was biodegraded before the second episode of migration occurred after the Middle Miocene tectonism. The later oil is believed to have been sourced by the Middle to Upper Jurassic Dingo Claystone. Biodegradation at this stage ceased or became insignificant due to temperature increase and reduction of meteoric water flow. Gas-condensate, sourced from Triassic or Lower Jurassic sediments may have migrated into the structure with this second oil although a more recent migration cannot be ruled out.

Williams, A.F.; Poynton, J.

1985-03-01

119

Migration Policy Institute  

Science.gov (United States)

Founded in 2001, the Migration Policy Institute (MPI) evolved from a program at the Carnegie Foundation for International Peace. Since its inception, the MPI has been dedicated to examining the trends and processes associated with the movement of various people worldwide. The homepage offers a wide array of resources for the general public, journalists, and academicians. Looking at the ÂIn Focus area on the homepage, visitors can download new working papers and reports with titles such as ÂThe New ÂBoat People and ÂImmigration Enforcement at the Worksite, Making it WorkÂ. From the homepage, users can also make their way to the Migration Information Source website which contains global migration data, country migration profiles, and a glossary of migration terms. Visitors with specific questions can also view a list of experts in a variety of topics related to migration and email them directly.

120

Migration of mineral oil, photoinitiators and plasticisers from recycled paperboard into dry foods: a study under controlled conditions.  

Science.gov (United States)

Migration from recycled paperboard was monitored after 2, 4 and 9 months of storage for six test foods industrially packed in five configurations, four with internal plastic films. After 9 months, the migration of mineral oil saturated hydrocarbons into foods directly packed in the paperboard amounted to 30-52 mg/kg, which corresponded to 65%-80% of those of a volatility up to that of the n-alkane C?? in the paperboard. The concentration of the migrated aromatic hydrocarbons in the foods ranged from 5.5 to 9.4 mg/kg. More than half of this migration occurred in the first 2 months. Differences between the foods amounted to mostly less than a factor of 2 and seemed to be related to porosity or permeability more than fat content. Nine photoinitiators were detected in the paperboard, of which eight migrated into the packed food at up to 24%. Several plasticisers were present in the recycled paperboard, but only butyl phthalates showed significant migration. After 9 months, up to 40% of diisobutyl phthalate and 20% of dibutyl phthalate migrated into the food with direct contact. The internal polyethylene film hardly slowed migration, but the film and the tray absorbed approximately three times more mineral oil than the food, despite constituting merely 4% of the mass of the pack. Oriented polypropylene strongly slowed migration: The highest migration of saturated hydrocarbons measured after 9 months (2.3 mg/kg) corresponded to only 3% of the content in the paperboard and included migrated polyolefin oligomeric saturated hydrocarbons. Coating of polypropylene with an acrylate further slowed the migration, but the migration from the paperboard was still detectable in four of the six samples. Polyethylene terephthalate was a tight barrier. PMID:23656414

Biedermann, Maurus; Ingenhoff, Jan-Erik; Zurfluh, Michael; Richter, Lydia; Simat, Thomas; Harling, Antje; Altkofer, Werner; Helling, Rüdiger; Grob, Koni

2013-05-08

 
 
 
 
121

Migration of mineral oil, photoinitiators and plasticisers from recycled paperboard into dry foods: a study under controlled conditions.  

UK PubMed Central (United Kingdom)

Migration from recycled paperboard was monitored after 2, 4 and 9 months of storage for six test foods industrially packed in five configurations, four with internal plastic films. After 9 months, the migration of mineral oil saturated hydrocarbons into foods directly packed in the paperboard amounted to 30-52 mg/kg, which corresponded to 65%-80% of those of a volatility up to that of the n-alkane C?? in the paperboard. The concentration of the migrated aromatic hydrocarbons in the foods ranged from 5.5 to 9.4 mg/kg. More than half of this migration occurred in the first 2 months. Differences between the foods amounted to mostly less than a factor of 2 and seemed to be related to porosity or permeability more than fat content. Nine photoinitiators were detected in the paperboard, of which eight migrated into the packed food at up to 24%. Several plasticisers were present in the recycled paperboard, but only butyl phthalates showed significant migration. After 9 months, up to 40% of diisobutyl phthalate and 20% of dibutyl phthalate migrated into the food with direct contact. The internal polyethylene film hardly slowed migration, but the film and the tray absorbed approximately three times more mineral oil than the food, despite constituting merely 4% of the mass of the pack. Oriented polypropylene strongly slowed migration: The highest migration of saturated hydrocarbons measured after 9 months (2.3 mg/kg) corresponded to only 3% of the content in the paperboard and included migrated polyolefin oligomeric saturated hydrocarbons. Coating of polypropylene with an acrylate further slowed the migration, but the migration from the paperboard was still detectable in four of the six samples. Polyethylene terephthalate was a tight barrier.

Biedermann M; Ingenhoff JE; Zurfluh M; Richter L; Simat T; Harling A; Altkofer W; Helling R; Grob K

2013-01-01

122

Cesarean section rate differences by migration indicators.  

UK PubMed Central (United Kingdom)

PURPOSE: To answer the question: are there differences in cesarean section rates among childbearing women in Canada according to selected migration indicators? METHODS: Secondary analyses of 3,500 low-risk women who had given birth between January 2003 and April 2004 in one of ten hospitals in the major Canadian migrant-receiving cities (Montreal, Toronto, Vancouver) were conducted. Women were categorized as non-refugee immigrant, asylum seeker, refugee, or Canadian-born and by source country world region. Stratified analyses were performed. RESULTS: Cesarean section rates differed by migration status for women from two source regions: South East and Central Asia (non-refugee immigrants 26.0 %, asylum seekers 28.6 %, refugees 56.7 %, p = 0.001) and Latin America (non-refugee immigrants 37.7 %, asylum seekers 25.6 %, refugees 10.5 %, p = 0.05). Of these, low-risk refugee women who had migrated to Canada from South East and Central Asia experienced excess cesarean sections, while refugees from Latin America experienced fewer, compared to Canadian-born (25.4 %, 95 % CI 23.8-27.3). Cesarean section rates of African women were consistently high (31-33 %) irrespective of their migration status but were not statistically different from Canadian-born women. Although it did not reach statistical significance, risk for cesarean sections also differed by time since migration (?2 years 29.8 %, >2 years 47.2 %). CONCLUSION: Migration status, source region, and time since migration are informative migration indicators for cesarean section risk.

Gagnon AJ; Van Hulst A; Merry L; George A; Saucier JF; Stanger E; Wahoush O; Stewart DE

2013-04-01

123

Possible migration of oil in the finely dispersed state  

Energy Technology Data Exchange (ETDEWEB)

The authors examine the theoretical possibility of hydrocarbon migration as a finely dispersed emulsion and give experimental data from spontaneous ordinary and chemical emulsification of individual hydrocarbons in aqueous solutions of olNa. In a natural environment, in the presence of corresponding conditions (alkalinity of the waters, the presence of certain oxygen-containing compounds in the OM of the rocks, etc.) microemulsions may be formed and then dispersed in the water and removed with the latter from the parent rocks to the trap.

Sergeevich, V.I.; Safronova, T.P.

1983-01-01

124

Occurrence of secondary magnetite within biodegraded oil  

Energy Technology Data Exchange (ETDEWEB)

Samples of solid bitumen from the Thornton Quarry (Illinois) and the Cynthia Quarry (Mississippi) were found to be strongly magnetic and to have rock magnetic properties suggesting that the magnetizable grains present are magnetite. Studies of magnetic isolates revealed that magnetite is present primarily as spherical crystal aggregates that appear identical to magnetite spherules isolated from remagnetized Paleozoic carbonate units from other localities. Organic geochemical analyses of the solid bitumen suggest an origin by microbial attack on what once was liquid crude oil. The occurrence of secondary magnetite as inclusions within solid bitumen suggests a relationship between crude oil biodegradation and development of that mineral in their samples. The authors infer that secondary magnetite in other geologic environments may be related to the presence of hydrocarbons. The discovery of a natural association of secondary magnetite and hydrocarbons has important implications for paleomagnetism and for petroleum exploration.

McCabe, C.; Sassen, R.; Saffer, B.

1987-01-01

125

Process for recovering hydrocarbons with air-hydrocarbon vapor mixtures  

Energy Technology Data Exchange (ETDEWEB)

An improved process is disclosed for recovering hydrocarbons from an air hydrocarbon vapor mixture such as the mixture of air and vaporized light hydrocarbon compounds expelled as a result of loading gasoline or the like into storage tanks and tank trucks. The air-hydrocarbon vapor mixture is caused to flow through a bed of solid adsorbent whereby the hydrocarbons are removed from the mixture and a residue gas stream comprised of substantially hydrocarbon-free air is produced. The substantially hydrocarbonfree air is vented to the atmosphere and a second bed of solid adsorbent having hydrocarbons adsorbed thereon is subjected to conditions which cause desorption of the hydrocarbons and thereby regeneration of the bed. The regeneration of the beds is accomplished by evacuating the beds with vacuum pumping whereby a major portion of the hydrocarbons are desorbed therefrom, subsequently introducing a small quantity of heated hydrocarbonfree air into the beds whereby additional hydrocarbons are stripped therefrom and then subjecting the bed to further evacuation by ejector jet pumping while continuing to evacuate the bed by vacuum pumping whereby yet additional hydrocarbons are desorbed therefrom. The air-hydrocarbon vapor mixture produced in the regeneration of the beds is contacted with a liquid absorbent whereby a major portion of the hydrocarbons are absorbed therefrom and recovered.

Dinsmore, H.L.; Long, G.W.; Peters, D.J.; Schwartz, R.E.

1982-05-25

126

Secondary glomerulonephritides.  

UK PubMed Central (United Kingdom)

This review of the secondary glomerulonephritides outlines presentation clues to assist the primary healthcare worker in making the diagnosis. Glomerulonephritis (GN) due to the following disorders will be described: hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency virus (HIV), sickle cell disease (SCD), and systemic lupus erythematosis (SLE).

Naicker S

2003-01-01

127

Renewable resources (hydrocarbons)  

Energy Technology Data Exchange (ETDEWEB)

Rising energy prices and an oil-based economy are cited as motivation to seek hydrocarbons similar to petroleum from renewable sources. Previous work (rubber tree, ethanol from carbohydrate crops, methanol from forest or plantation trees) is reviewed as well as past and current efforts to find species of plants with high hydrocarbon content, in which the molecular weight is similar to that of petroleum. Yields of hydrocarbons obtainable (4 tons/acre/yr in the case of rubber trees) are cited as well as biochemical pathways leading to various hydrocarbons. Guayule rubber plants are discussed as well as the economics and technology involved in processing. Specific ''Oil Plants'' are discussed in some detail. These include Euphorbia species and croton. Algae (Botryococcus braunii) is cited as containing 75% hydrocarbons (dry weight), which after processing yields glycerol, pigment, and protein. Plants such as sunflower, soya bean, palm, etc. yield vegetable oils which may be used as a diesel substitute. It is concluded that decisions concerning the use of oil containing plants for fuel will be based on economic and political considerations. 23 references. (MJJ)

Hall, D.O.

1981-06-01

128

Hydrocarbon fuel systems  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a low Reid Vapor Pressure liquid gasoline for use in a standard carbureted internal combustion engine. It comprises: a priming agent and a hydrocarbon mixture having an intermediate carbon range relative to C{sub 4}-C{sub 12} fuel; the intermediate carbon range consisting essentially of C{sub 6}-C{sub 10} hydrocarbons with C{sub 9} and C{sub 10} paraffinic hydrocarbons being present in the mixture; the gasoline having a boiling point range of 121{degrees} F.-345{degrees} F. at 1 atmosphere pressure; and the priming agent consisting of a hydrocarbon selected from the priming agent consisting of C{sub 4} and C{sub 5} hydrocarbons and mixtures thereof and the priming agent being present in a minimum effective amount for raising the front end volatility of the gasoline to a minimum level for cold engine starting with the minimum effective amount being less than that required for C{sub 4}-C{sub 12} gasoline.

Talbert, W.L.

1991-05-14

129

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)

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

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

2009-04-01

130

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

Science.gov (United States)

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.

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

2013-02-01

131

Sulfur removal from hydrocarbons.  

UK PubMed Central (United Kingdom)

Liquid and gaseous hydrocarbon streams are treated to remove COS by contacting the hydrocarbon streams with an aqueous solution of selective H2S-absorbent and a COS absorbent/hydrolyzer whereby COS is hydrolyzed to H2S and CO2 and said products are absorbed by the H2S absorbent in the selective range thereof. Preferably, the H2S absorbent is an alkanolamine, especially methyldiethanolamine, and the COS absorbent/hydrolyzer is an organic liquid, especially diisopropanolamine. The resultant hydrocarbon stream can be further treated in one or more subsequent steps with aqueous caustic solution containing, in some steps, a primary alkanolamine, especially monoethanolamine, to remove acid gases and, in particular, to reduce the COS content to below 1,000 ppb.

PEARCE ROSCOE L; WOLCOTT RICHARD A

132

Viscosity of pure hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

Accurate viscosity measurements have been performed on eight pure hydrocarbons at atmospheric pressure in the temperature range 20-150/sup 0/C, or up to approximately 20/sup 0/C below the boiling point of the hydrocarbon, by use of an absolute oscillating viscometer. The hydrocarbons are cyclohexane and benzene and the n-alkanes of hexane, heptane, octane, decane, dodecane, and tetradecane. The viscosities are described with a modified Arrhenius equation, and the deviation in fit is 0.12% or less. The accuracy is estimated to be 0.33-0.56%. The lowest viscosities are assumed to have the highest deviation. Literature data reported by Dymond and Young normally fit our viscosities within our estimated accuracy. Other literature viscosities tend to be higher than our results, especially for the n-alkanes.

Knapstad, B.; Skjolsvik, P.A.; Oye, H.A.

1989-01-01

133

Apparatus for recovering hydrocarbons from air-hydrocarbon vapor mixtures  

Energy Technology Data Exchange (ETDEWEB)

An improved process and apparatus for recovering hydrocarbons from an air-hydrocarbon vapor mixture such as the mixture of air and vaporized light hydrocarbon compounds expelled as a result of loading gasoline or the like into storage tanks and tank trucks. The air-hydrocarbon vapor mixture is caused to flow through a bed of solid adsorbent whereby the hydrocarbons are removed from the mixture and a residue gas stream comprised of substantially hydrocarbon-free air is produced. The substantially hydrocarbonfree air is vented to the atmosphere and a second bed of solid adsorbent having hydrocarbons adsorbed thereon is subjected to conditions which cause desorption of the hydrocarbons and thereby regeneration of the bed. The flow pattern of the inlet airhydrocarbon vapor mixture and the bed of solid adsorbed being regenerated are periodically changed so that when the bed through which the inlet air-hydrocarbon mixture is flowing becomes loaded with adsorbed hydrocarbons, the inlet air-hydrocarbon mixture is caused to flow through the bed which has just been regenerated. The regeneration of the beds is accomplished by evacuating the beds with vacuum pumping whereby a major portion of the hydrocarbons are desorbed therefrom, subsequently introducing a small quantity of heated hydrocarbon-free air into the beds whereby additional hydrocarbons are stripped therefrom and then subjecting the bed to further evacuation by ejector jet pumping while continuing to evacuate the bed by vacuum pumping whereby yet additional hydrocarbons are desorbed therefrom. The airhydrocarbon vapor mixture produced in the regeneration of the beds is contacted with a liquid absorbent whereby a major portion of the hydrocarbons are absorbed therefrom and recovered. Apparatus for carrying out the process of the invention is also provided.

Dinsmore, H.L.; Long, G.W.; Peters, D.J.; Schwartz, R.E.

1981-04-14

134

Structural development and hydrocarbon entrapment in the Surma Basin/Bangladesh (Northwest Indo Burman Fold Belt)  

Energy Technology Data Exchange (ETDEWEB)

The Surma Basin in the Northeast of Bangladesh is a proven Miocene Gasprovince and was structurally stamped by the contemporaneous interference of two major tectonic movements, ie. the emerging Shillong Massif in the North and the West-prograding mobile Indo-Burman Fold Belt. Basin relief, structural elements, growth and style as well as geochemical data with respect to hydrocarbons, source rocks and maturity are discussed. Related to the clear cut pre- and post-early Plicene situation, change of migration pattern and coincidence between hydrocarbon generation, migration, accumulation and trap growth are analysed. Finally, the further prospectivity of the Surma Basin is commented upon.

Miller, K.; Elahi, M.

1984-02-01

135

Microtubules in Cell Migration.  

UK PubMed Central (United Kingdom)

Migration is a polarized cellular process that opposes a protrusive front edge to a retracting trailing edge. From the front to the rear, actin-mediated forces sequentially promote cell protrusion, adhesion, contraction, and retraction. Over the past decade, microtubules have revealed their pivotal role in cell migration. Through their roles in cell mechanics, intracellular trafficking, and signaling, microtubules participate in all essential events leading to cell migration. The front-rear polarization of microtubule functions relies on the asymmetric regulation of microtubule dynamics and stability; the asymmetric distribution of microtubule-associated protein complexes; and finally, the orientation of the microtubule network along the axis of migration. Microtubule network polarity controls the establishment and maintenance of the spatial and temporal coordination of migration events and is therefore the key to persistent directed migration. This review summarizes our current understanding of the functions of microtubules in persistent cell migration and of the migration-associated signals that promote microtubule network polarization. Expected final online publication date for the Annual Review of Cell and Developmental Biology Volume 29 is October 06, 2013. Please see http://www.annualreviews.org/catalog/pubdates.aspx for revised estimates.

Etienne-Manneville S

2013-07-01

136

The Migration Game  

Science.gov (United States)

This site features an interactive Migration Game created by the Migratory Bird Center at the Smithsonian National Zoological Park. In it, you can help Wanda the Wood Thrush travel from her winter home in Costa Rica to her summer home in Maryland by answering questions regarding migration in general and specific migratory habits of the wood thrush.

2008-01-01

137

Migration Networks in Senegal  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper investigates the importance and role of migration networks in Senegal using a new nationally representative survey conducted in 2006-2007. Using a sample of 1707 Senegalese households I explore potentially differential effects of networks on international migration depending on their char...

Chort, Isabelle

138

Biliary stent migration into the abdominal wall: a case report.  

UK PubMed Central (United Kingdom)

Biliary stent migration occurs in about 5% of patients. The most common complications secondary to stent migration are pancreatitis, small bowel perforation and peritonitis. We report the case of a patient presenting with an abdominal wall abscess secondary to migration of a biliary stent. Direct abdominal radiography, abdominal ultrasound and CT scan have proved very useful in the diagnosis, providing the correct localisation of the stent in the left rectus muscle of the abdominal wall that led to a surgical approach under local anaesthesia for the removal, and abscess formation surrounding the stent. The patient was discharged on the day after surgery. After reviewing the literature concerning this rare complication, the Authors conclude that closer monitoring of patients with biliary prostheses is needed to prevent the migration and the consequent serious complications.

Minutolo V; Gagliano G; Buttafuoco A; Minutolo O; Mosca F; Puleo S

2009-07-01

139

Hydrocarbon fuel detergent  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a hydrocarbon fuel composition comprising: a hydrocarbon fuel; and a detergent amount of a detergent comprising an alkenylsuccinimide prepared by reacting an alkenylsuccinic acid or anhydride with a mixture of amines, wherein at least 90 weight percent of the alkenyl substituent is derived from an olefin having a carbon chain of from 10 to 30 carbons or mixtures thereof, and wherein the alkenylsuccinic acid or anhydride is reacted with the mixture of amines at a mole ratio of 0.8 to 1.5 moles of the amines per mole of the alkenylsuccinic acid or anhydride.

Meyer, G.R.; Lyons, W.R.

1990-01-23

140

Hydrotreating hydrocarbon feedstocks  

Energy Technology Data Exchange (ETDEWEB)

An improved hydrotreating catalyst, and a process for using thereof, comprises a conventional Group VIA and Group VIIIA metal oxide or metal sulfide, deposited on an inorganic refractory support and about 0.1% by weight to about 7% by weight of the catalyst of a promoter comprising a halogenated metal selected from the Group consisting of halogenated metals of Group IB, IIB, IIIB, titanium and tin. The presence of the promoter results in greater degree of desulfurization and in CCR reduction of hydrocarbon feedstocks, especially highly aromatic petroleum residue and synthetically-derived hydrocarbons, e.g., coal liquids.

Heck, R.H.; Rosinski, E.J.; Shih, S.S.

1984-04-10

 
 
 
 
141

Tomography wave equation migration  

Energy Technology Data Exchange (ETDEWEB)

With the aid of both the 2-D Fourier transform theory and the CT technique-projection and reconstruction principle in image processing, the author uses scaler wave equation to develop CT migration formulas-projection and reconstruction expressions for seismic data processing. Applying the formulas to the migration of a horizontal seismic stack section, the author can obtain a conventional migration section, or a migration section without noise or with interpolated traces. This method is available to migrate the horizontal stack section which has low S/N ratio or unequal group intervals. It has advantages such as high S/N ratio, no boundary reflection effect and so forth. The theoretical and real data processing results obtained using this method are shown in this paper.

Huaxiang, M.

1990-01-01

142

Migration and Environmental Hazards.  

UK PubMed Central (United Kingdom)

Losses due to natural hazards (e.g., earthquakes, hurricanes) and technological hazards (e.g., nuclear waste facilities, chemical spills) are both on the rise. One response to hazard-related losses is migration, with this paper offering a review of research examining the association between migration and environmental hazards. Using examples from both developed and developing regional contexts, the overview demonstrates that the association between migration and environmental hazards varies by setting, hazard types, and household characteristics. In many cases, however, results demonstrate that environmental factors play a role in shaping migration decisions, particularly among those most vulnerable. Research also suggests that risk perception acts as a mediating factor. Classic migration theory is reviewed to offer a foundation for examination of these associations.

Hunter LM

2005-03-01

143

Liquid hydrocarbons containing a fluorescent compound  

Energy Technology Data Exchange (ETDEWEB)

Method of determining the presence of one or more liquid hydrocarbons in a liquid hydrocarbon mixture, the method having the step of adding to the hydrocarbon or hydrocarbons to be detected a minor amount of an alkylated isodibenzanthrone.

Beyer, R.E.; Magoulas, J.P.

1981-07-14

144

Migration of mineral oil from printed paperboard into dry foods: survey of the German market. Part II: advancement of migration during storage  

UK PubMed Central (United Kingdom)

In April 2010, 119 samples of dry foods packed in paperboard boxes and stored at ambient temperature were collected from the German market. The migration of mineral oil from the recycled paperboard and printing ink was analyzed for the first time immediately after collection and reported in Vollmer et al. (Eur Food Res Technol 232:175–182, 2011). It frequently exceeded 10–100 times the 0.6 mg/kg limit for mineral oil saturated hydrocarbons (MOSH) derived from the WHO/JECFA evaluation published in 2002. As most samples were far from the end of the shelf life, analyses were repeated 4 months later and a third time either at the expiry date or after 16 months. The average MOSH concentration in the foods increased from 8.9 to 14.3 mg/kg (by 60 %), which indicates a rapid migration during the first months of storage, but also a further increase up to the end of the shelf life. The maximum migration reached 101 mg/kg. In the third measurement, the average concentration of the migrated mineral oil aromatic hydrocarbons was 2.2 mg/kg, with a maximum at 13.2 mg/kg. Most types of food behaved similarly, differences mostly reflecting the types of packaging rather than the food properties. Exceptions were table salt (hardly any migration) and noodles (low migration). Internal bags with an aluminum foil or PET layer were complete barriers. Migration through plastic with vapor-deposited aluminum or acrylate-coated polypropylene was reduced, but still sometimes exceeded 0.6 mg/kg. Internal bags of polyethylene had a weak effect on slowing migration, but acted as a sink for mineral oil: Although on average they only constituted 1.1 % of the total mass of the packs, they absorbed nearly 40 % of the migrating hydrocarbons. Polypropylene was a similar sink. In addition, it strongly slowed migration, but at the third measurement the 0.6 mg/kg limit was nevertheless exceeded in 11 of 16 samples. Polyolefin oligomeric saturated hydrocarbons (POSH) from the plastic or heat-sealable layer, largely branched hydrocarbons similar to MOSH, often migrated in the range of 1–5 mg/kg.

Biedermann Maurus; Ingenhoff Jan-Erik; Dima Giovanna; Zurfluh Michael; Biedermann-Brem Sandra; Richter Lydia; Simat Thomas; Harling Antje; Grob Koni

2013-03-01

145

Additives for hydrocarbon oils  

Energy Technology Data Exchange (ETDEWEB)

An additive for inhibiting sedimentation and retarding degradation of hydrocarbon oils as evidenced by discoloration comprises the reaction product of an alkoxyalkylamine with an epihalohydrin at a temperature from about 40/sup 0/C to about 150/sup 0/C in the presence of an inorganic base.

Kwong, G.W.; Levy, J.

1981-08-18

146

Additives for hydrocarbon oils  

Energy Technology Data Exchange (ETDEWEB)

An additive for inhibiting sedimentation and retarding degradation of hydrocarbon oils as evidenced by discoloration comprises the reaction product of a poly(oxyalkylene)amine with an epihalohydrin at a temperature from about 40/sup 0/C to about 150/sup 0/C in the presence of an inorganic base.

Kwong, G. W.

1980-12-16

147

Excited states in hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

In this brief review we first summarize some pertinent features of the photophysical properties of excited states of hydrocarbons and the mechanisms by which they transfer energy to solutes and then review their yields and their behavior under fast-electron irradiation conditions. 33 refs.

Lipsky, S.

1987-01-01

148

Hydrocarbon options emerge  

Energy Technology Data Exchange (ETDEWEB)

Europe stole the scene at last week`s International Chlorofluorocarbon (CFC) and Halon Alternatives Conference in Washington as attendees learned more about an accelerating shift to low-cost hydrocarbon refrigerants by European equipment manufacturers. Udo Wenning, representing German refrigerator market leader Bosch-Siemens, told the conference that hydrocarbons-isobutane as refrigerant and cyclopentane to blow the insulating foam-are now used in 90% of German production. Wenning says that in all performance parameters, hydrocarbons match the hydrochlorofluorocarbon (HCFC) and hydrofluorocarbon (HFC) replacements favored in the U.S. and Japan and that, unlike HCFCs and HFCs they have low global warming potential. Their Achille`s heel is flammability, Wenning says. American equipment manufacturers aiming to sell a new generation of equipment designed for the new HFC refrigerants sought to amplify concern over flammability at the conference. {open_quotes}In a society as litigious as ours, we do not see a future for flammable refrigerants,{close_quotes} says a representative of air conditioner manufacturer Carrier. Hydrocarbon supporters such as Greenpeace say the risks are mananageable.

Fairley, P.

1995-11-01

149

Zeroing in on hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

The increasing costs of remediating contaminated sites has stimulated research for cost-reducing techniques in soil investigation and cleanup techniques. MAP Environmental Research has developed a technology using ground penetrating radar in combination with in house developed software to locate and define the extent of hydrocarbon contamination. This article discusses the new technology. 2 figs.

Roest, I.P.B. van der; Brasser, D.J.S.; Wagebaert, A.P.J.; Stam, P.H. [MAP Environmental Research BV, Arnhem (Netherlands)

1997-05-01

150

Optrode for sensing hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

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.

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

1987-01-01

151

Optrode for sensing hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

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.

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

1988-01-01

152

Anomalous magnetization by chemical and microbial processes in hydrocarbon seepage environments  

Energy Technology Data Exchange (ETDEWEB)

Anomalous magnetization has been reported from several commercial hydrocarbon accumulations. Although the processes responsible for such anomalous magnetization are relatively poorly understood, the formation and destruction of magnetic mineral assemblages can be predicted from thermodynamic criteria and microbiologic activity. Under the influence of hydrocarbons, magnetite and pyrrhotite are the most important magnetic minerals formed, and the most abundant magnetic mineral destroyed is hematite. Hence, the invasion of hydrocarbons may result in anomalous magnetization relative to the total magnetization prior to hydrocarbon invasion, depending on the amounts of authigenic magnetite and pyrrhotite formed relative to the amounts of hematite destroyed. Anomalous magnetization may be present vertically above the location of hydrocarbon seepage or may be laterally displaced where the migration of the escaping hydrocarbons is influenced by forces in addition to buoyancy. This is likely where local or regional groundwater flow has a significant lateral component, or where hydrocarbon seepage is funnelled by inclined beds and faults of high permeability. Magnetism may be generated also by natural and anthropogenic processes that have no relationships to an underlying or adjacent hydrocarbon accumulation. Consequently, anomalous magnetization, even if associated with a hydrocarbon accumulation, may or may not be genetically related to it.

Machel, H.G. (Univ. of Alberta, Edmonton (Canada)); Burton, E.A. (Northern Illinois Univ., De Kalb (United States))

1991-03-01

153

Forced Migration Projects  

Science.gov (United States)

The Forced Migration Projects (FMP), operating under the auspices of the Open Society Institute (OSI), monitor developments in the Americas, the former Yugoslavia, and the former Soviet Union to identify the social, political, and economic conditions that cause the forced dislocations of people. This Website provides background information about the projects as well as full-text access to several FMP publications including The Forced Migration Monitor, a series of special reports on refugees and migration, recent news and articles on germane issues, and FM Alert, an electronic bulletin service. In addition, the site compiles a list of refugee-related links and hosts a discussion forum.

154

Signs of Migration  

Science.gov (United States)

Students research and examine the practical and instinctual characteristics of the migration patterns of many different animal species. The will also work in groups to illustrate their research and make presentations.

Kqed

2007-08-30

155

International Organization for Migration  

Science.gov (United States)

The International Organization for Migration (IOM) is an intergovernmental body "committed to the principle that humane and orderly migration benefits migrants and society." IOM currently has 69 member states and 48 observer states worldwide. In addition, numerous international governmental organizations and non-governmental organizations hold observer status with IOM, assisting in the study, development, and enactment of migration policies. The IOM Website offers a wealth of information on the organization and its initiatives. The site posts official IOM news releases and statements and provides access to IOM publications including books, surveys, studies, journals, newsletters, and informational updates. IOM also hosts MIGRATION WEB, a searchable and browseable gateway to a bevy of information resources on the Internet.

156

Migration = cloning; aliasiing  

DEFF Research Database (Denmark)

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.

Hüttel, Hans; Kleist, Josva

1999-01-01

157

Migration og etnicitet  

DEFF Research Database (Denmark)

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 på nationalstaten, dens suverænitet og kapaciteten hos dens institutioner til henholdsvis at regulere bevægelser over statsgrænser og til at definere de former for fællesskab, som præger de enkelte samfund. I sociologien har man tidligere primært koncentreret sig om studier af migrationsprocessen som 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.

Christiansen, Connie CarØe

2004-01-01

158

Defining lifestyle migration  

Directory of Open Access Journals (Sweden)

Full Text Available This paper seeks to provide a conceptual framework for studying migration to the Algarve by Northern Europeans. ‘Lifestyle migration’ is suggested as a generic term for this trend, which is part of a recent but flourishing global social phenomenon. I also point to the glaring gap in the literature as far as empirical studies based in the Algarve are concerned, and make suggestions for a research agenda.

Kate Torkington

2010-01-01

159

Migration and Narration  

Directory of Open Access Journals (Sweden)

Full Text Available The following article aims to work out the main narrative techniques of “telling migration”. The conclusions drawn on the subject of migration and narration are based on a one-year field work study, combining participant observation with interviewing. This study took place in New Zealand concentrating on German immigrants between 1936 and 1996. The main source for my analysis given in this paper is provided by 102 people I interviewed. The texts of these biographically-focussed interviews allowed me to work not only on an ethnographical history of migration but also to gain insights into peoples’ experiences, and over and above that, to learn what kind of stories and techniques of storytelling emigration creates. The book focuses on a comparatively wide time frame of sixty years (Boenisch- Brednich 2001). This makes it possible to analyse very different periods of migration and groups of migrants, contrasting social categories as well as exploring differences in education, milieu, age and gender. Furthermore, it becomes obvious that although all migrants were leaving Germany and arriving in New Zealand, they experienced what were in effect very different countries through time – different Germanys, different New Zealands. To work out the changing reasons for migrating (work migration, refuge, global lifestyle, etc.) inside western societies is a major theme the book is aiming for. A second approach is to investigate migration from the perspective of focussing on everyday life, an investigation on the basis of personal experiences, such as “work, housing, food, celebrations, social life”. A special focus is set on the analysing of “mental narratives” as key stories, examples, comparatives etc. The central questions of this project were: What kind of strategies do people use to cope with a major changes in their biography, as constituted by emigration? What does integration really mean and how does it work for different groups? What kind of collective and individual stories does migration create? In which ways does retroperspection work as a technique for creating autobiographies in oral transmission?

Brigitte Boenisch-Brednich

2002-01-01

160

METHOD FOR OBTAINING AROMATIC HYDROCARBONS FROM A HYDROCARBON MIXTURE  

UK PubMed Central (United Kingdom)

The invention relates to a process for obtaining aromatic hydrocarbons selected from benzene, toluene, xylene and ethylbenzene mixtures thereof from a hydrocarbon mixture which additionally comprises nonaromatic hydrocarbons and high boilers, comprising the steps of (A) providing a hydrocarbon mixture a1 and an extractive solvent a2 composed of N-formylmorpholine, (B) extractively distilling the hydrocarbon mixture a1 with the extractive solvent to obtain a mixture b1 of extractive solvent and the aromatic hydrocarbons, said mixture comprising high boilers, and a mixture b2 comprising nonaromatic hydrocarbons, (C) distilling the mixture b1 of extractive solvent and aromatic hydrocarbons obtained in step (B) to obtain one or more fractions c1 composed of aromatic hydrocarbons and the extractive solvent c2 which comprises high boilers, (D) removing a substream d1 from the extractive solvent c2 and recycling the extractive solvent c2 into the extractive distillation (B), (E) extracting the substream d1 of the extractive solvent with water to obtain an aqueous extract phase el essentially free of high boilers and an organic phase e2 comprising the high boilers, (F) distilling the aqueous extract phase e1 and recovering the extractive solvent a2 in purified form, and recycling the extractive solvent into the extractive distillation (B), wherein performance of step (E) is preceded by performance of a distillation in which a fraction composed of very high-boiling hydrocarbons is removed from the substream d1 of the extractive solvent.

STABEL UWE; DECKERT PETRA

 
 
 
 
161

Migration Type III  

Science.gov (United States)

Migration type IIIMigration of objects embedded in disks (and the accompanying eccentricity evolution) is becoming a major theme in planetary system formation.The underlying physics can be distilled into the notion of disk-planet coupling via Lindblad resonances, which launch waves, sometimes spectacular spiral shock waves in gas disks. The wave pattern exchanges angular momentum with the planet. That causes (i) migration, (ii) eccentricity evolution, and (iii) gap opening by sufficiently massive planets.A competing source of disk-planet interaction, the corotationaltorques, are much less conspicuous (corotation does not produce easilydetectable waves, as galaxy observers can attest) and have often been missed in the analysis of planet migration. If spiral waves are like waves at Goleta beach, then the corotation acts more like a stealthy riptide. Corotationalflows lie at the basis of a new, surprisingly rapid, mode of migration (type III),superseding the standard type II migration (with a gap), and revising the speed of type I migration (without a gap). The talk will contain results obtained at KITP, e.g., an analytical derivation of da/dt in type III motion. It will be illustrated by videos of high-resolution numerical simulations obtained with different implementations of the Piecewise Parabolic Method hydrodynamics.

Artymowicz, Pawel

2004-03-01

162

Hydrocarbon seepage and carbonate mound formation: a basin modelling study from the Porcupine Basin (offshore Ireland)  

Energy Technology Data Exchange (ETDEWEB)

This study assesses whether the growth of deep-water carbonate mounds on the continental slope of the north Atlantic may be associated with active hydrocarbon leakage. The carbonate mounds studied occur in two distinct areas of the Porcupine Basin, 200 km offshore Ireland, known as the Hovland-Magellan and the Belgica areas. To evaluate the possible link between hydrocarbon leakage and mound growth, we used two dimensional cross-section and map-based basin modelling. Geological information was derived from interpretation of five seismic lines across the province as well as the Connemara oilfield. Calibration data was available from the northern part of the study area and included vitrinite reflectance, temperature and apatite fission track data. Modelling results indicate that the main Jurassic source rocks are mature to overmature for hydrocarbon generation throughout the basin. Hydrocarbon generation and migration started in the Late Cretaceous. Based on our stratigraphic and lithologic model definitions, hydrocarbon migration is modelled to be mainly vertical, with only Aptian and Tertiary deltaic strata directing hydrocarbon flow laterally out of the basin. Gas chimneys observed in the Connemara field were reproduced using flow modelling and are related to leakage at the apices of rotated Jurassic fault blocks. The model predicts significant focussing of gas migration towards the Belgica mounds, where Cretaceous and Tertiary carrier layers pinch out. In the Hovland-Magellan area, no obvious focus of hydrocarbon flow was modelled from the 2D section, but drainage area analysis of Tertiary maps indicates a link between mound position and shallow Tertiary closures which may focus hydrocarbon flow towards the mounds. (author)

Naeth, J. [Forschungszentrum, Juelich (Germany); GeoForschungZentrum, Potsdam (Germany); Primio, R. di [GeoForschungZentrum, Potsdam (Germany); Horsfield, B. [GeoForschungZentrum, Potsdam (Germany); Schaefer, R.G. [Forschungszentrum, Juelich (Germany); Shannon, P.M.; Bailey, W.R. [University College, Dublin (Ireland). Dept. of Geology; Henriet, J.P. [University of Gent (Belgium). Renard Centre of Marine Geology

2005-04-01

163

Hydrocarbon gas processing  

Energy Technology Data Exchange (ETDEWEB)

This patent describes an improvement in a process for the separation of a gas containing methane, C{sub 2} components, C{sub 3} components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of the methane and a relatively less volatile fraction containing a major portion of the C{sub 2} components, C{sub 3} components and heavier components. In this process the gas is cooled under pressure to provide a cooled stream; the cooled stream is expanded to a lower pressure whereby it is further cooled; and the further cooled stream is fractionated at the lower pressure whereby the major portion of the C{sub 2} components, C{sub 3} components and heavier hydrocarbon components is recovered in the relatively less volatile reaction. In the improvement, the gas is cooled sufficiently to partially condense it. Said partially condensed gas is separated thereby to provide a vapor stream and a condensed stream.

Campbell, R.E.; Wilkinson, J.D.; Hudson, H.M.

1989-12-26

164

Sulfur removal from hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

A method is described for treating liquid and gaseous hydrocarbon streams containing H/sub 2/S, CO/sub 2/ and COS to remove a substantial portion of the H/sub 2/S and COS, and slip a substantial portion of the CO/sub 2/ which comprises: contacting the hydrocarbon stream containing H/sub 2/S, CO/sub 2/ and COS with a solution of methyldiethanolamine, which is a selective absorbent for H/sub 2/S with respect to CO/sub 2/, and which solution also contains diisopropanolamine, an organic liquid COS absorbent which absorbent converts by hydrolysis the COS to H/sub 2/S and CO/sub 2/.

Pearce, R.L.; Wolcott, R.A.

1989-02-28

165

Hydrocarbons from plants  

Energy Technology Data Exchange (ETDEWEB)

We have suggested that certain plants rich in hydrocarbon-like materials might be cultivated for renewable photosynthetic products. Two species were selected for experimental plantations: Euphorbia lathyris, an annual from seed and Euphorbia tirucalli, a perennial from cuttings. The yield from each species is over 10 barrels of oil/acre/year without genetic or agronomic improvement. In addition to plants, there are trees, such as species of Copaifera in Brazil and other tropical areas, which produce a diesel-like oil upon tapping. Each tree produces approximately 40 liters of hydrocarbon per year, and this material can be used directly by a diesel-powered car. Further efforts to develop plants as alternate energy sources are underway, as well as a continuing search for additional plant species throughout the world which have a similar capability.

Calvin, M.

1980-11-01

166

Membrane separation of hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

Mixtures of heavy oils and light hydrocarbons may be separated by passing the mixture through a polymeric membrane. The membrane which is utilized to effect the separation comprises a polymer which is capable of maintaining its integrity in the presence of hydrocarbon compounds and which has been modified by being subjected to the action of a sulfonating agent. Sulfonating agents which may be employed will include fuming sulfuric acid, chlorosulfonic acid, sulfur trioxide, etc., the surface or bulk modified polymer will contain a degree of sulfonation ranging from about 15 to about 50%. The separation process is effected at temperatures ranging from about ambient to about 100.degree. C. and pressures ranging from about 50 to about 1000 psig.

Chang, Y. Alice (Des Plaines, IL); Kulkarni, Sudhir S. (Hoffman Estates, IL); Funk, Edward W. (Highland Park, IL)

1986-01-01

167

Hydrocarbon contact injuries.  

UK PubMed Central (United Kingdom)

Cutaneous injury caused by exposure to gasoline and other hydrocarbons is a clinical entity with potentially life-threatening effects. We report four cases of such injury. One patient developed full-thickness skin loss following gasoline immersion, and another developed severe systemic complications following contact with a carburetor cleaning solvent. Initial therapy should consist of removal of solvent-containing clothing and extensive lavage or soaking with water, followed by wound care that is generally similar to that used in the treatment of partial-thickness burns. In most cases this includes debridement, topical antimicrobial agents, and dressing changes. Severe pulmonary, cardiovascular, neurologic, renal, and hepatic complications may accompany hydrocarbon absorption, particularly in cases involving gasolines containing lead additives. Therefore immediate surgical debridement should be considered if there is suspicion of continued absorption of toxic compounds from the wound.

Hansbrough JF; Zapata-Sirvent R; Dominic W; Sullivan J; Boswick J; Wang XW

1985-03-01

168

Hydrocarbon bioremediation -- An overview  

Energy Technology Data Exchange (ETDEWEB)

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.

Reisinger, H.J. [Integrated Science and Technology, Inc., Marietta, GA (United States)

1995-12-31

169

Hydrocarbon gas processing  

Energy Technology Data Exchange (ETDEWEB)

This patent describes an improvement in a process for the separation of a gas containing methane, C{sub 2} components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of the methane and a relatively less volatile fraction containing a major portion of the C{sub 2} components and heavier components. In the improvement the gas is cooled sufficiently to partially condense it.

Campbell, R.E.; Wilkinson, J.D.; Hudson, H.M.

1989-09-26

170

Modified liquid hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

Modified liquid hydrocarbon fuel, in particular aviation kerosene, having a reduced tendency to undergo mist formation when subjected to shock, contains from 0.05% to 2% of its weight of polymer microgel particles of defined characteristics, the microgel polymer preferably being an addition copolymer of one or more main monomers with a minor proportion, e.g. 0.0005% to 0.1% of the total monomers, of one or more monomers which are multifunctional with respect to the polymerization reaction.

Waite, F. A.

1984-06-05

171

Biogeochemistry of Halogenated Hydrocarbons  

Science.gov (United States)

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.

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

2003-12-01

172

Removal of surfactants from hydrocarbons with alcohol  

Energy Technology Data Exchange (ETDEWEB)

A method is disclosed for removing hydrocarbon-soluble anionic surfactants from gasoline or kerosene boiling range hydrocarbons. The method comprises (a) contacting a hydrocarbon mixture containing surfactants with a lower alcohol which is miscible with the hydrocarbon mixture to extract the surfactants; (b) contacting the mixture with water or caustic solution to extract the lower alcohol and surfactants from the hydrocarbon mixture; (c) separating the water or caustic solution from the hydrocarbons; and (d) removing the hydrocarbons.

Aiello, R.P.; Poling, D.E.; Stefanidakis, G.

1984-02-07

173

Detecting hydrocarbon microseepage using remotely sensed data  

Energy Technology Data Exchange (ETDEWEB)

Many petroleum reservoirs leak, and the upwardly migrating hydrocarbons and associated fluids can produce a series of chemical changes that may affect plant physiology and the mineralogical and physical attributes of the overlying strata. Alterations manifested the surface depend on the composition of both the upwardly migrating fluid and the strata overlying the leaking reservoir. These alterations may appear on airborne spectroradiometric or satellite multispectral data as tonal (mineral or plant spectral) or textural (geomorphic or plant ecological) anomalies, or both. Examples include: (1) bleaching of red beds due to loss of hematite and/or anomalous clay mineral distributions in strata overlying petroleum accumulations at Lisbon Valley, Utah, and at Cement and Velma fields, Oklahoma; (2) mineral alterations such as replacement of calcium sulfates by calcite at Cement, Oklahoma, and Limestone Buttes, Gypsum Plain, Texas, resulting in anomalous geomorphology; and (3) geobotanical manifestations caused by soil chemistry variations resulting in anomalous plant communities above Lost River gas field, West Virginia, or physiological alteration (stunting) of plant communities such as at Patrick Draw field, Wyoming. The diagnostic visible and near-infrared absorption features exhibited by iron oxides, clay minerals, and botanical assemblages permit airborne and satellite-borne sensors to be used to distinguish and map spatial patterns of these materials, and form the basis for remote detection of surficial phenomena that may indicate hydrocarbon microseepage. The ability to detect these anomalies using remotely sensed data depends on the susceptibility of the surface to alteration, the inherent heterogeneity of the surface, and the degree of exposure.

Merin, I.S.; Segal, D.B.; Staskowski, R.J.; Everett, J.R.

1986-05-01

174

Enzymatic transformation of hydrocarbons by methanotrophic organisms  

Energy Technology Data Exchange (ETDEWEB)

Soluble methane monooxygenase from a facultative methane-utilizing organism, Methylobacterium sp. CRL-26 or R6, catalyzed the NAD(P)H-dependent epoxidation/hydroxylation of a variety of hydrocarbons, including terminal alkenes, internal alkenes, substituted alkenes, branch-chain alkenes, alkanes (C1-C8), substituted alkanes, branch-chain alkanes, carbon monoxide, ether, cyclic and aromatic compounds. The NAD -linked dehydrogenases such as formate dehydrogenase or secondary alcohol dehydrogenase in the presence of formate or secondary alcohol, respectively, regenerated NAD/NADH required for the methane monooxygenase in a coupled enzymes reactions. Oxidation of secondary alcohols to the corresponding methylketones in methanotrophs is catalyzed by an NAD -dependent, zinc-containing, secondary alcohol hydrogenase. Primary alcohols were oxidized to the corresponding aldehydes by a phenazine methosulfate-dependent, pyrollo quinoline quinone (methoxatin or PQQ) containing, methanol dehydrogenase. Oxidation of aldehydes (C1 to C10) to the corresponding carboxylic acids is catalyzed by a heme-containing aldehyde dehydrogenase. Methanotrophs have been considered potentially useful for single cell protein (SCP), amino acids, and biopolymer production at the expense of growth on cheap and readily available C1 compounds. 80 references, 1 figure, 6 tables.

Patel, R.N.; Hou, C.T.

1983-01-01

175

Synthesis of hydrocarbons from dimethyl ether: selectivities towards light hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

An efficient hydrocarbon synthesis process has been developed at the University of Akron using dimethyl ether as the starting feedstock. This UA/EPRI`s DTH (Dimethyl Ether to Hydrocarbons) process has significant advantages over its counterpart methanol conversion process in the areas of heat duties, hydrocarbon selectivities, product yield, and reactor size. Lower olefins are the intermediate products in the conversion of dimethyl ether to aromatic hydrocarbons. C{sub 2}-C{sub 4} olefins and paraffins can be selectively produced by varying the operating parameters of the process, viz., temperature, pressure, DME concentration in the feed, space time, catalyst-to-inert packing ratio, etc. The present work focuses on the effect of key process variables on the dimethyl ether conversion to low molecular weight hydrocarbons in a fixed bed microreactor system over ZSM-5 type zeolite catalyst. Experimental results with respect to gaseous hydrocarbon product yields and selectivities have been examined in this study. 5 refs., 5 figs.

Sardesai, A.; Tartamella, T.; Lee, S. [University of Akron, Akron, OH (United States). Dept. of Chemical Engineering

1996-06-01

176

Globalization, Migration and Development  

Directory of Open Access Journals (Sweden)

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 women)of 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.

George, Susan; Samuel, John

2002-01-01

177

Hydrocarbon source potential in Brazilian margin basins  

Energy Technology Data Exchange (ETDEWEB)

Twenty thousand samples from the Brazilian continental shelf basins were analyzed to characterize and evaluate the hydrocarbon source potential of the areas. The geochemical evaluation of the rock and oil samples was performed by organic carbon determinations, Rock-Eval pyrolysis, vitrinite reflectance, thermal alteration index, liquid and gas chromatographies, gas chromatography-mass spectrometry, and carbon isotope analyses. Three source rock systems have been identified: lower Neocomian shales deposited in a continental environment, upper Neocomian shales grading from continental to lagoonal environment, and Aptian shales related to evaporitic and lacustrine sequences. Upper Cretaceous and Tertiary open marine slope sediments are not considered as source rocks. Locally, these sediments present high organic carbon content but show an extremely poor hydrocarbon yield. Anoxic depositional conditions, nevertheless, can be traced locally along some levels of the Santonian to Cenomanian shales and marls. These sediments are generally immature in the Brazilian margin basins and no oil was generated from this section. Three oil families were distinguished through oil-to-oil and oil-to-source rock correlations: the lower Neocomian continental type, the upper Neocomian continental to lagoonal type, and the Aptian evaporitic to lacustrine related sequences. The geochemical studies, together with geologic and geophysical data, provided the basis to display some models for the migration pathways and habitat of oils in the Brazilian margin basins.

Mello, M.R.; Estrella, G.D.O.; Gaglianone, P.C.

1984-04-01

178

Hydrocarbon habitat of the paleoproterozoic Franceville Series, Republic of Gabon  

Energy Technology Data Exchange (ETDEWEB)

The abnormally high rate of organic carbon deposition that occurred between 2.22 and 2.06 Ga contributed to one of the most impressive accumulations of organic matter of its age, namely, the 2.1 Ga old FB Formation of the Franceville Series, Gabon. The weakly metamorphosed, dominantly pelitic FB Formation ranges in thickness from 400 m to 1000 m, covers more than 30,000 km{sup 2}, and consists of about 80% marine shale with 0.5-15% total organic carbon. About 2.0 Ga ago, the FB Formation generated prolific amounts of petroleum liquids. The coincidence of uranium-bearing aqueous solutions with the first and principal episode of liquid hydrocarbon migration led to the localization of world class uranium ores at Oklo. Relatively high-grade ore developed in petroleum-type structural traps, which ca. 1968 {+-} 50 Ma served as loci for fifteen natural nuclear fission reactors at Oklo and nearby Bangombe. Hydrothermal solutions circulating about the reactors during their operation resulted in a second episode of local production/mobilization of liquid hydrocarbon. A third episode of hydrocarbon migration occurred during dolerite (diabase) dyke intrusion at Oklo ca. 977 to 971 Ma {+-} 27 Ma ago. Altogether, eight different types of carbonaceous substances (two kerogens, six solid bitumens) are identified in the black shales, uranium ores, and fossil reactors. (author)

Mossman, D.J.

2001-01-15

179

Electron trapping in alcohol clusters in. gamma. -irradiated n-propanol-hydrocarbon glasses at 77 K  

Energy Technology Data Exchange (ETDEWEB)

A study has been made of trapped electrons in n-propanol-hydrocarbon mixture glasses at 77 K by the optical absorption method. The yields of electrons trapped in alcohol clusters (e sub(alc)sup(-)) were measured for several ..gamma..-irradiated n-propanol-hydrocarbon glasses, where the yields of trapped electrons in these neat hydrocarbon glasses at 77 K are known to range from 0.015 to 1.1 G units. The results show that the yields of e sub(alc) sup(-) in the mixture glasses does not depend on the trapped electron yields in neat hydrocarbon glasses. Thus, it is concluded that electron migration from relaxed hydrocarbon matrix traps into alcohol clusters is not the major process for e sub(alc) sup(-) formation in the systems studied here. The major process for e sub(alc) sup(-) formation may be attributed to quasi-free electron scavenging by alcohol clusters and electron migration from unrelaxed hydrocarbon traps into alcohol clusters. Both ir-induced and isothermal changes in the e sub(alc) sup(-) yield have also been investigated. These investigations indicate that there is a correlation between the observed change in the e sub(alc) sup(-) yield and the matrix viscosity.

Ito, M.; Kimura, T.; Fueki, K. (Nagoya Univ. (Japan). Faculty of Engineering)

1981-09-15

180

Electron trapping in alcohol clusters in ?-irradiated n-propanol-hydrocarbon glasses at 77 K  

International Nuclear Information System (INIS)

[en] A study has been made of trapped electrons in n-propanol-hydrocarbon mixture glasses at 77 K by the optical absorption method. The yields of electrons trapped in alcohol clusters (e sub(alc)sup(-)) were measured for several ?-irradiated n-propanol-hydrocarbon glasses, where the yields of trapped electrons in these neat hydrocarbon glasses at 77 K are known to range from 0.015 to 1.1 G units. The results show that the yields of e sub(alc) sup(-) in the mixture glasses does not depend on the trapped electron yields in neat hydrocarbon glasses. Thus, it is concluded that electron migration from relaxed hydrocarbon matrix traps into alcohol clusters is not the major process for e sub(alc) sup(-) formation in the systems studied here. The major process for e sub(alc) sup(-) formation may be attributed to quasi-free electron scavenging by alcohol clusters and electron migration from unrelaxed hydrocarbon traps into alcohol clusters. Both ir-induced and isothermal changes in the e sub(alc) sup(-) yield have also been investigated. These investigations indicate that there is a correlation between the observed change in the e sub(alc) sup(-) yield and the matrix viscosity

1981-09-15

 
 
 
 
181

A Generic Process Migration Algorithm  

Directory of Open Access Journals (Sweden)

Full Text Available Process migration has been advocated as a means of improving multicomputer configuration performance. The optimized migration algorithm utilized in migration event has direct effect on the efficiency and deployment of the process migration system. However, every design has preference factors results in concentration on specific aspect of the migration algorithm. There is no generic migration algorithm which could satisfy all circumstances with almost reasonable costs. This paper reviews the major issues which constitute the developer concerns when implementing a process migration algorithm. This examination indicates the existence of similarity in all process migration algorithms. A new migration algorithm is given and compared to the other algorithms. This algorithm attempts to integrate the significant features of the existing algorithms to form a generic algorithm.

Amirreza Zarrabi

2012-01-01

182

forced-migration-history  

Science.gov (United States)

This new, UK-based, moderated mailing list serves as a forum for discussions on population displacements in 20th-century European history, "and to explore the inter-relationship of forced migration/resettlement/repatriation with nationalism, state formation and the construction of social identities." While the moderators believe that most of the subscribers will be involved in migration studies, history, geography, demography, and anthropology or sociology, scholars from other fields and different geographical and historical time periods are most welcome. Users will find archived messages and subscription information at the site.

183

Migration, klima og sundhed  

DEFF Research Database (Denmark)

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. Udgivelsesdato: 2009-Oct-26

Tellier, Siri; Carballo, Manuel

2009-01-01

184

Unix Application Migration Guide  

CERN Document Server

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

Microsoft. Redmond

2003-01-01

185

Hydrocarbon conversion process  

Energy Technology Data Exchange (ETDEWEB)

Processes are claimed for the production of highly aromatic petroleum fractions from various petroleum feedstocks suitable for catalytic cracking in a fluidized catalytic cracking unit and for producing needle coke from various hydrocarbon cracking stocks. The heavy gas oil from a first fluidized catalytic cracking unit is subjected to further catalytic cracking in a separate fluid catalytic cracking unit at temperatures in the range of 565/sup 0/ to 650/sup 0/ C producing light olefins and a heavy gas oil consisting essentially of aromatic components suitable for the production of needle coke.

Lionetti, T.A.; Schrader, C.H.

1983-06-14

186

Aromatics from Light Hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

A thermal Pyroform process is described. Pyroform is a process for the production of aromatic liquids or the joint production of olefins and aromatics, starting from ethane, propane or ethane-propane mixtures. Butane can also be used, should this be economical. The process has two basic versions: thermal Pyroform and thermal/ catalytic Pyroform. Depending on the feedstock and product slate requirements, a plant can be designed to include one or both options. This approach offers the versatility to handle most light hydrocarbon components.

Che, S.C.; Cronin, P.; Froment, G.F.; Minet, R.G.; Tsai, F.W.

1985-05-01

187

ADVANCES IN HYDROCARBON TECHNOLOGIES  

Directory of Open Access Journals (Sweden)

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.

Martin Bajus

2007-01-01

188

Nitrated polycyclic aromatic hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

Nitrated polycyclic aromatic hydrocarbons (nitro-PAH) are among the most potent mutagens reported in the literature and within the last few years have been recognized as being emitted from many combustion sources. Within the short time since the initial recognition of nitro-PAH as a possible environmental hazard, hundreds of scientific papers describing their chemistry and biology have been published. This book focuses those papers into a practical working guide that deals with the analytical chemistry of nitro-PAH, their synthesis, and mutagenic and carcinogenic properties. Chapters have been prepared by twelve internationally recognized scientists, each one writing in their specific area of expertise.

White, C.M. (ed.)

1985-01-01

189

Migration scenarii in extrasolar systems  

Directory of Open Access Journals (Sweden)

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.

Crida A.

2011-01-01

190

Secondary recovery method  

Energy Technology Data Exchange (ETDEWEB)

Hydrocarbons are recovered from a subterranean hydrocarbon-bearing formation penetrated by an injection well and a production well by displacing hydrocarbons toward the production well using a drive fluid such as water or brine, thickened with a copolymer of acrylamide and diacetone acrylamide alkoxylated with an alkylene oxide or glycidol, optionally sulfated or sulfonated. If desired, said drive fluid can be saturated with carbon dioxide, nitrogen, natural gas or mixtures of these gases at the injection pressure.

Hunter, W.D.

1984-02-07

191

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

192

Method for cracking hydrocarbon compositions using a submerged reactive plasma system  

Energy Technology Data Exchange (ETDEWEB)

A method for cracking a liquid hydrocarbon composition (e.g. crude oil) to produce a cracked hydrocarbon product. A liquid hydrocarbon composition is initially provided. An electrical arc is generated directly within the hydrocarbon composition so that the arc is entirely submerged in the composition. Arc generation is preferably accomplished using a primary and secondary electrode each having a first end submerged in the composition. The first ends of the electrodes are separated from each other to form a gap therebetween. An electrical potential is then applied to the electrodes to generate the arc within the gap. A reactive gas is thereafter delivered to the arc which forms a bubble around the arc. Gas delivery may be accomplished by providing a passageway through each electrode and delivering the gas through the passageways. The arc and gas cooperate to produce a plasma which efficiently cracks the hydrocarbon composition.

Kong, Peter C. (Idaho Falls, ID)

1997-01-01

193

Net Migration Statistics  

Science.gov (United States)

Bar chart of countries ranked by their net migration flow as of 2005. While the highest net in-flow is generally into large rich countries (USA, Spain, Germany etc.) Afghanistan had the second highest net inflow thanks to returning refugees.

194

MEXICAN MIGRATION PROJECT  

Science.gov (United States)

The Mexican Migration Project is designed to make timely, high-quality data on documented and undocumented Mexican migrants available to researchers and policy analysts. Each year since 1987 the project has administered a semi-structured interview schedule to representative sampl...

195

Forced Migration Online  

Science.gov (United States)

Designed to function as a comprehensive website that provides access to various resources on forced human migration, this site is provided through the courtesy of the staff at the Refugee Studies Centre at the University of Oxford. While the users of this site will encounter a seamlessly integrated resource, the site contains four separate components. These elements include a searchable digital library, a searchable catalogue with descriptions of and links to Internet-based resources, and a series of geographic and thematic research guides. The homepage offers users access to all of these resources, along with a sidebar that features relevant upcoming events as the International Day of Older Persons. The site also affords visitors access to the full-text of three important publications in the field: Disasters, Forced Migration Review, and International Migration Review (some archived journals are several years behind the current issue). It is worth noting that the homepage also contains a link to a nice introductory essay by Sean Loughna titled "What is Forced Migration?"

196

Is Migration Feminized?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In the context of Turkey’s accession to the EU, the issue of potential migration from Turkey and its impact upon European labor markets became one of the concerns of the EU, considering Turkey’s growing population and young labor force. In 2011, half a century after the bi-lateral agreement between...

Toksöz, Gülay

197

Residence, Migration, and Earnings.  

Science.gov (United States)

|Examination of the effects of including place of origin, current residence, and place of migration in the Sewell-Hauser basic model of socioeconomic achievement indicated that place of current residence had an important influence on socioeconomic achievement, particularly on earnings. (DS)|

Wang Shiang Yun, Charlotte; Sewell, William H.

1980-01-01

198

Practical Data Migration  

CERN Multimedia

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.

Morris, Johny

2012-01-01

199

Conflict and forced migration  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this thesis, I aim to improve our understanding of two phenomena, the emergence of violent conflicts and forced migration. The first chapter describes the logic of economic investigation followed throughout the thesis. In the second chapter, I analyze the conflict-enhancing role of income inequal...

Maystadt, Jean-François

200

Brain Migration Revisited  

Science.gov (United States)

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…

Vinokur, Annie

2006-01-01

 
 
 
 
201

Religion, migration og integration  

DEFF Research Database (Denmark)

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 integrationsspørgsmål.

Borup, JØrn

2010-01-01

202

Hydrocarbon gas processing  

Energy Technology Data Exchange (ETDEWEB)

The processing of gas streams containing hydrocarbons and other gases of similar volatility to recover components such as ethane, propane and heavier hydrocarbons from a residue gas containing methane is disclosed. In prior art processes, it has been customary to cool incoming raw feed gas and to separate the desired products by distillation. A part of the needed cooling is obtained by expanding the raw feed gas from a high feed pressure to a lower pressure at which distillation occurs. In the present invention, the raw feed gas is divided into two gaseous streams before expansion. The first stream is expanded in the usual fashion and supplied to the demethanizer as a mid-column feed. The remaining part is cooled to substantial condensation. The condensed stream is expanded and supplied to the demethanizer column above the feed point of the first stream. The split vapor feed provides unexpected advantages in reducing the risk of carbon dioxide icing in the demethanizer column, thus either eliminating or reducing the need for prior CO2 removal. Alternately, without increasing the risk of carbon dioxide icing, ethane recovery can be increased.

Campbell, R.E.; Wilkinson, J.D.

1981-07-14

203

Hydrocarbon gas processing  

Energy Technology Data Exchange (ETDEWEB)

This patent describes an improvement in a process for the separation of a gas containing methane, C/sub 2/ components, C/sub 3/ components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of the methane and C/sub 2/ components and a relatively less volatile fraction containing a major portion of the C/sub 3/ components and heavier components. In this process: the gas is cooled under pressure to provide a cooled stream; the cooled stream is expanded to a lower pressure whereby it is further cooled; and the further cooled stream is fractionated at the lower pressure whereby the major portion of the C/sub 3/ components and heavier hydrocarbon components is recovered in the relatively less volatile fraction. In the improvement the gas is cooled sufficiently to partially condense it; and the partially condensed gas is separated to provide a vapor stream and a condensed stream; the vapor stream is thereafter divided into gaseous first and second streams; the gaseous first stream is cooled to condense substantially all of it and is thereafter expanded to the lower pressure; the expanded cooled first stream is then directed in heat exchange relation with a warmer distillation stream; the distillation stream is cooled by the first stream sufficiently to partially condense it.

Campbell, R.E.; Wilkinson, J.D.; Hudson, H.M.

1989-08-08

204

Magnetotelluric exploration for hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

The magnetotelluric (MT) method utilizes naturally occurring low frequency electromagnetic energy to determine the electrical resistivity of the earth's subsurface. The resistivity distribution of the subsurface is then interpreted in terms of rock type and geologic structure. MT derived resistivity data are usually integrated with other geophysical results, and with surface and subsurface geologic data if available, to arrive at an interpretation. This paper reviews the basic relationships that govern the application of MT to hydrocarbon exploration; the electrical properties of rocks, MT energy sources, and briefly, MT theory. Data acquisition and processing and field procedures are covered. By measuring the complete vector electromagnetic field, an impedance tensor may be calculated which, when evaluated as a function of frequency, samples the electrical characteristics of the earth as a function of depth through the skin depth relationship. The impedance is simply related to an apparent resistivity. The use of a tensor impedance relationship is necessitated by the distortion imposed on the electromagnetic field by lateral variations in subsurface resistivity. Data analysis and modeling techniques have been developed which aid in the interpretation of the resistivity tensor in terms of complex structure. The paper includes a discussion of current usage, concluding with representative case studies, which illustrate the application of MT to hydrocarbon exploration problems.

Orange, A.S.

1989-02-01

205

Migration strategies of insects.  

Science.gov (United States)

Physiological and ecological results from a variety of species are consistent with what seem to be valid general statements concerning insect migration. These are as follows: (i)During migration locomotory functions are enhanced and vegetative functions such as feeding and reproduction are suppressed. (ii) Migration usually occurs prereproductively in the life of the adult insect (the oogenesis-flight syndrome). (iii)Since migrant individuals are usually prereproductive, their reproductive values, and hence colonizing abilities, are at or near maximum. (iv) Migrants usually reside in temporary habitats. (v)Migrants have a high potential for population increase, r, which is also advantageous for colonizers. (vi)Both the physiological and ecological parameters of migration are modifiable by environmental factors (that is, phenotypically modifiable)to suit the prevailing conditions. Taken together, these criteria establish a comprehensive theory and adumbrate the basic strategy for migrant insects. This basic strategy is modified to suit the ecological requirements of individual species. Comparative studies of these modifications are of considerable theoretical and practical interest, the more so since most economically important insects are migrants. No satisfactory general statements can as yet be made with respect to the genotype and migration. Certainly we expect colonizing populiations to possess genotypes favoring a high r, but genotypic variation in r depends on the heritabilities of life table statistics, and such measurements are yet to be made (10, 53). The fact that flight duration can be increased by appropriate selection in Oncopeltus fasciatus, and the demonstration of additive genetic variance for this trait in Lygaeus kalmii, suggest that heritability studies of migratory behavior would also be worth pursuing. Most interesting of course, will be possible genetic correlations between migration and life history parameters. Also, migration often transports genotypes across long distances with considerable mixing of populations. An understanding of its operation therefore carries with it implications for population genetics, zoogeography, and evolutionary theory. Finally, at least parts of the above general theory would seem to be applicable to forms other than insects. Bird and insect migrations, for example, are in many respects ecologically and physiologically similar. Birds, like insects, emphasize locomotory. as opposed to vegetative functions during long-distance flight; the well-known Zugenruhe or migratory restlessness is a case in point. Further, many birds migrateat nigt at a time when they would ordinarily roost(vegetative activity). Because their life spans exceed single seasons, bird migrants are not prereproductive in the same sense that insect migrants are, and hence reproductive values do not have the same meaning(but note that some insects are also interreproductive migrants). The situaion is complicated further by the fact that in many birds adult survivorship is virtually independent of age so that colonizing ability tends to be also (10, 54). Nevertheless, birds arrive on their nesting grounds in reproductive condition with the result that migration is a colonizing episode. It is also phenotypically modifiable by environmental factors, some of which, for example, photoperiod, influence insects as well (55). The similarities between birds and insects thus seem sufficient to indicate, at least provisionally, that the theory developed for insects applies also to birds with appropriate modifications for longer life span and more complex social behavior; comparisons between insects and fish (56) lead to the same conclusion. In birds especially, and also in other forms, various functions accessory to migration such as reproductive endocrinology, energy budgets, and orientation mechanisms have been studied extensively (55, 56). But there is need in vertebrates for more data andtheoy on the ecology and physiology of migratory behavior per se in order tobetter understand its evolution and its role in

Dingle, H

1972-03-24

206

The International Organization for Migration in Global Migration Governance  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Poulsen, Sofie Havn; Andersen, Lise

207

Graphic approach to determination of hydrocarbon maturation in overthrust terrains  

Energy Technology Data Exchange (ETDEWEB)

With the current exploration efforts in areas of overthrust tectonics, it is important to evaluate, efficiently and effectively, the effects of thrust-related thermal perturbations on hydrocarbon maturation. A simple graphic technique, which combines Lopatin diagrams with theoretical models of temperatures in overthrust regimes, allows one to develop relatively detailed models for the timing of hydrocarbon maturation in overthrust terrains. These models provide the critical combination between rigorous consideration of thermal perturbations and simplification necessary for routine application. The approach described here is applicable not only in cases of simple overthrusting at the surface, but can also be modified to include the effects of multiple thrusting events, sheets thrust in the subsurface, and post-thrusting erosion. All of these models provide critical constraints on the timing of maturation and migration, as well as information on the maturity of potential source rocks.

Furlong, K.P.; Edman, J.D.

1984-11-01

208

ELECTROLYTE SOLUTION FOR LITHIUM ION SECONDARY BATTERY, LITHIUM ION SECONDARY BATTERY, FLUOROALKANE DERIVATIVE AND GELLING AGENT  

UK PubMed Central (United Kingdom)

The electrolyte solution for a lithium ion secondary battery according to the present invention contains a nonaqueous solvent, a lithium salt and a compound represented by the general formula (Z) shown below. Thereby, a lithium ion secondary battery having high battery characteristics and simultaneously achieving a high safety as well can be provided. R-SO2-Ar1-O-R1 (Z) wherein Ar1 denotes a substituted or nonsubstituted divalent aromatic group having 5 to 30 atoms of the nucleus(es) R1 denotes a saturated or unsaturated monovalent hydrocarbon group having 1 to 20 carbon atoms and R denotes a saturated or unsaturated monovalent hydrocarbon group having a perfluoroalkyl group and having 2 to 22 carbon atoms.

OHASHI ASAMI; ISHII YOSHIYUKI; OKAMOTO HIROAKI; MORITA YUKI

209

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).

1989-01-01

210

THE ROMANIAN MIGRATIONAL EVOLUTION PHENOMENON  

Directory of Open Access Journals (Sweden)

Full Text Available In our contemporary democratic society the migration phenomenon meets unknown valences in any previous societies. Free will and right to self-determination, much exploited by the XX century society., raised the possibility of interpretation of migration

Sorlescu Mariana; Cristian Raluca

2009-01-01

211

Hydrocarbon sensors and materials therefor  

Energy Technology Data Exchange (ETDEWEB)

An electrochemical hydrocarbon sensor and materials for use in sensors. A suitable proton conducting electrolyte and catalytic materials have been found for specific application in the detection and measurement of non-methane hydrocarbons. The sensor comprises a proton conducting electrolyte sandwiched between two electrodes. At least one of the electrodes is covered with a hydrocarbon decomposition catalyst. Two different modes of operation for the hydrocarbon sensors can be used: equilibrium versus non-equilibrium measurements and differential catalytic. The sensor has particular application for on-board monitoring of automobile exhaust gases to evaluate the performance of catalytic converters. In addition, the sensor can be utilized in monitoring any process where hydrocarbons are exhausted, for instance, industrial power plants. The sensor is low cost, rugged, sensitive, simple to fabricate, miniature, and does not suffer cross sensitivities.

Pham, Ai Quoc (San Jose, CA); Glass, Robert S. (Livermore, CA)

2000-01-01

212

Method of migrating seismic records  

Energy Technology Data Exchange (ETDEWEB)

The present invention provides a method of migrating seismic records that retains the information in the seismic records and allows migration with significant reductions in computing cost. The present invention comprises phase encoding seismic records and combining the encoded seismic records before migration. Phase encoding can minimize the effect of unwanted cross terms while still allowing significant reductions in the cost to migrate a number of seismic records.

Ober, Curtis C. (Las Lunas, NM); Romero, Louis A. (Albuquerque, NM); Ghiglia, Dennis C. (Longmont, CO)

2000-01-01

213

Trade, Aid, Remittances and Migration  

Digital Repository Infrastructure Vision for European Research (DRIVER)

I investigated whether migration is interrelated with trade, aid and remittances so that any policies that consider trade, aid and remittances also affect the decision to migrate. We developed and estimated an empirical model of Turkish migration to Germany and tested the model for the 1969-2004, us...

Akkoyunlu, Sule

214

Temporary and Circular Migration: Ireland  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The current study is part of an EU-wide study intended to promote understanding of temporary and circular migration by Third Country nationals. Most migration policy development in Ireland has been related to migration that is ultimately viewed as temporary. Ireland’s policy decision to prioritise m...

QUINN, EMMA

215

METHOD FOR OBTAINING AROMATIC HYDROCARBONS FROM A HYDROCARBON MIXTURE  

UK PubMed Central (United Kingdom)

The invention relates to a process for obtaining aromatic hydrocarbons selected from benzene, toluene, xylene and ethylbenzene and mixtures thereof from a hydrocarbon mixture which additionally comprises nonaromatic hydrocarbons and high boilers, comprising the steps of (A) providing a hydrocarbon mixture a1 and an extractive solvent a2 composed of N-formylmorpholine, (B) extractively distilling the hydrocarbon mixture a1 with the extractive solvent to obtain a mixture b1 of extractive solvent and the aromatic hydrocarbons, said mixture comprising high boilers, and a mixture b2 comprising nonaromatic hydrocarbons, (C) distilling the mixture b1 of extractive solvent and aromatic hydrocarbons obtained in step (B) to obtain one or more fractions c1 composed of aromatic hydrocarbons and the extractive solvent c2 which comprises high boilers, (D) removing a substream d1 from the extractive solvent c2 and recycling the extractive solvent c2 into the extractive distillation (B), (E) extracting the substream d1 of the extractive solvent with water to obtain an aqueous extract phase e1 essentially free of high boilers and an organic phase e2 comprising the high boilers, (F) distilling the aqueous extract phase e1 and recovering the extractive solvent a2 in purified form, and recycling the extractive solvent into the extractive distillation (B), wherein a substream e2' is removed from the organic phase e2 comprising the high boilers and recycled into the extraction of step (E), the amount of the organic phase e2' thus circulated being such that, when the substream d1 composed of extractive solvent comprising high boilers, water and circulated stream e2' is dispersed, the aqueous extract phase e1 essentially freed of high boilers forms as a disperse phase, and the organic phase composed of high boilers e2 as a continuous phase.

STABEL UWE; DECKERT PETRA

216

Thermal decomposition of cadmium alkyl diperoxides in aromatic hydrocarbons  

International Nuclear Information System (INIS)

[en] Thermal decomposition of cadmium diperoxides, using as an example dipropyl peroxicadmium (1) and dibutyl peroxicadmium (2), has been studied. The process is conducted in toluene and isopropyl benzene. The peroxides (1, 2) in aromatic hydrocarbons decompose with a measurable rate at the temperature above 313 K. Decomposition of cadmium alkyl diperoxides takes place in two macrostages according to coordinated mechanism both by means of intramolecular regrouping with ?-hydrogen atom migration and as a result of intermolecular interaction. Cadmium acylate is one of the main metal-containing products of thermal decomposition

1983-01-01

217

Modeling of hydrocarbon fueling  

International Nuclear Information System (INIS)

[en] We have compared a database of rate coefficients for CH4 with experiments on PISCES-A to understand the role of carbon-based impurities in determining the fueling profile of carbon-dominated machines. A three-dimensional Monte Carlo model that embodies the Ehrhardt-Langer CH4 breakup scheme has been developed. The model has been compared with spectroscopic observations of the spatial variation of the hydrocarbon product decay rates, and reasonable agreement has been found. The comparison is sensitive to the non-Maxwellian electron distribution and to observed spatial inhomogeneities in the electron density and temperature profiles. Applications of the model to parameters characteristic of the tokamak scrape-off layer are presented

1989-10-02

218

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.)

1986-01-01

219

Petroleum hydrocarbon cracking catalyst  

UK PubMed Central (United Kingdom)

The invention discloses a petroleum hydrocarbon catalyzing and cracking catalyst, which is composed of 0-70% of clay, 5-90% of inorganic oxide binder and 10-70% of molecular sieves in weight percent,wherein, the molecular sieves comprises ZSM-5 zeolite, Y-shaped zeolite and 1-25% of silicoaluminophosphate (SAPO) molecular sieves in weight percent the molar composition of the framework of the SAPO molecular sieves is expressed in the oxide anhydrous chemical formula as follows: Al2O3:yP2O5:zSiO2 the molar composition before roasting and depriving the template agent is expressed in the oxideanhydrous chemical formula as follows: (x1R1+x2R2):Al2O3:yP2O5:zSiO2, wherein, R1 and R2 are template agent existing in the molecular sieve crystal pore canal R1 is diethylamine and R2 is dipropylamine the value of x1 plus x2 equals to 0.01-5.0 the quotient of x1 and x2 is 0.1-20 the value of y equals to 0.01-1.5 and the value of z equals to 0.01-30. The X-ray diffraction data of the molecular sieve before roasting and depriving the template agent at least comprise a diffraction peak shown in Table A and the X-ray diffraction data after roasting and depriving the template agent at leastcomprise the diffraction peak shown in Table B. The catalyst can strengthen the cracking of petroleum hydrocarbon, and the yield of low-carbon olefin, in particular ethylene and propylene, is high inthe products.

MINGGANG LI; YIBIN LUO; XUHONG MU; LISHENG LI; FENGMEI ZHANG; JIUSHUN ZHANG; XINGTIAN SHU

220

The effect of overpressure on hydrocarbon trapping in the chalk of the greater Ekofisk area (Norway)  

Energy Technology Data Exchange (ETDEWEB)

The Chalk of the Greater Ekofisk Area is a relatively closed system for fluid movements and it is interpreted that large pressure cells have developed, all characterised by their own pressure regime, fluid type and trapping potential. In such a system where overpressures. mainly generated by compaction, reach very high values, we try to understand what are the implications on the trapping mechanisms and hydrocarbon distribution. We conclude that, today, the aquifer is near static and that there is no significant regional hydrodynamic flow. During the Tertiary period the Chalk system has evolved from hydrostatic conditions to high overpressure conditions. This transformation had a primary control on chalk permeability and fluid movements. A significant lateral fluid transmissibility within the Chalk existed during the main phase of oil migration (Miocene) because at that time, the Chalk was more permeable and more homogeneous than today. The pressure distribution observed today corresponds to a closed system where the lateral fluid flow is restricted, whilst the pressure is controlled by the seal capacity. The hydrocarbon distribution in the Greater Ekofisk Area is the result of a dynamic process dependent on burial, hydrocarbon generation and migration, diagenesis and seal integrity. This process controlled both chalk porosity and hydrocarbon trapping. Oil accumulations in the area are complex and are dependent more on the complexity of the reservoirs in terms of geometry, porosity and capillary pressure, all inherited since Miocene time, rather than on the present-day migration system. (author)

Caillet, G. [Elf Exploration Production, Centre Scientifique et Technique Jean Feger, 64 - Pau (France); Bramwell, N. [Phillips Petroleum Norway, Tananger (Norway); Meciani, L. [Agip, Milano (Italy)

1999-04-01

 
 
 
 
221

THE SEASONAL LABOR MIGRATION  

Directory of Open Access Journals (Sweden)

Full Text Available This paper investigates the cross-border mobility and migration phenomenon between Romania and Hungary. The research includes available data for 2010. It was based on direct observation and interviews with people involved in this process. The research has examined two main dimensions of the phenomenon of cross-border mobility. Firstly, we are speaking of the existence of a phenomenon of cross-border mobility of the commuting type of the labor force from Romania to Hungary, mainly for seasonal (agricultural) activities. Secondly, we are dealing with the cross-border mobility of Romanian citizens who have purchased homes in the border area in Hungary, but are working in Romania. Seasonal cross-border migration of the labor force in the border area between Romania and Hungary does not yet have a greater scale, but is present.

Ciprian Panzaru

2012-01-01

222

Diasporas, Migration & Identities  

Science.gov (United States)

Funded with substantial monies provided by the Arts and Humanities Research Council in the United Kingdom, the Diasporas, Migrations & Identities research programme is designed "to research, discuss and present issues related to diasporas and migration, and their past and present impact on subjectivity and identity, culture and the imagination, place and space, emotion, politics and sociality." While the programme is no longer actively funded, visitors can view the fruits of their academic labors on this site in the "Publications" area. Visitors to this section can view their annual reports and their working papers. Scholars and others can make their way through ten working papers, which include the titles "Here we go-but where? The possibilities of diaspora in the field of sport" and "London's Chinatown: Diaspora, Identity and Belonging". The site also contains a "Links" area, which contains a healthy selection of external links to other like-minded research institutes and centers.

223

Migration of interplanetary dust.  

UK PubMed Central (United Kingdom)

We numerically investigate the migration of dust particles with initial orbits close to those of the numbered asteroids, observed trans-Neptunian objects, and comet Encke. The fraction of silicate asteroidal particles that collided with the Earth during their lifetime varied from 11% for 100 micron particles to 0.008% for 1 micron particles. Almost all asteroidal particles with diameter d >/= 4 microns collided with the Sun. For migrating asteroidal dust particles, the peaks in semimajor axis distribution at the n:(n + 1) resonances with Earth and Venus, and the gaps associated with the 1:1 resonances with these planets are more pronounced for larger particles. The probability of collisions of cometary particles with the Earth is smaller than for asteroidal particles, and this difference is greater for larger particles.

Ipatov SI; Mather JC; Taylor PA

2004-05-01

224

Dispersal and migration  

Directory of Open Access Journals (Sweden)

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 ti

Schwarz, C. J.; Bairlein, F.

2004-01-01

225

Diffusion of hydrocarbons from HDPE and f-HDPE geomembranes  

Energy Technology Data Exchange (ETDEWEB)

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.

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

226

Migration Process Evolution in Europe  

Directory of Open Access Journals (Sweden)

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.

Carmen Tudorache

2006-01-01

227

Epithelial delamination and migration  

Science.gov (United States)

Metastasis is the most deadly phase of cancer progression, during which cells detach from their original niche to invade distant tissues, yet the biological processes underlying the spread of cancer are still poorly understood. The fruit fly Drosophila melanogaster provides important insights in our understanding of how epithelial cells migrate from their original location and find their way into surrounding and distant tissues in the metastatic process. Here we review recent studies on the mechanisms of migration of embryonic hemocytes, the macrophage-like immuno-surveillance cells, during normal development and wound healing. We highlight the interesting finding that hydrogen peroxide (H2O2) has been identified as the driving force for hemocyte chemotaxis. We also give a special emphasis to studies suggesting the concept that hemocytes, together with the tumor microenvironment, act as potential inducers of the epithelial delamination required for tumor invasion. We propose that cell delamination and migration could be uncoupled from loss of cell polarity via a tumor-related inflammatory response.

Parisi, Federica

2011-01-01

228

Hydrocarbon systems in the southwest Maracaibo Basin, Colombia  

Energy Technology Data Exchange (ETDEWEB)

Multiple hydrocarbon systems are recognized in the Colombian portion of the Maracaibo Basin (Catatumbo subbasin). Hydrocarbons, trapped in wrench controlled, faulted anticlines, were generated from two different source horizons, in two distinct source kitchens, and migrated along different pathways into Cretaceous and Tertiary reservoirs. Cretaceous reservoirs are shallow-marine sandstones and limestones characterized by low matrix porosity and permeability. They are separated from Tertiary reservoirs by a thick shale seal that limited cross-stratal migration. Tertiary reservoirs are fluvial-deltaic sandstones with good to excellent porosities and permeabilities. Geochemical data suggest the presence of two oil families. Family 1 oils were sourced locally from Cretaceous marine shales and limestones and account for most of the oil in Tertiary and Cretaceous reservoirs. Family 2 oils are only present in Tertiary reservoirs in the southern part of the subbasin, and are interpreted to be sourced from Paleocene terrestrial shales and coals. Two distinct migration systems operated to fill Catatumbo traps. Family 1 oils migrated from local Cretaceous source beds along fractures and faults that developed concurrently with trap formation. Family 2 oils were sourced from outside the Catatumbo subbasin. Maturation data and burial history modelling indicate that Paleocene rocks are immature in the Catatumbo subbasin. Maturation levels increase westward into the Maracaibo Basin and along the axis of the North Andean foredeep. The proximity of Rio Zulia Field to the North Andean foredeep, and lack of Tertiary-sourced oils in other Catatumbo fields suggest that the North Andean foredeep is the primary source for these oils.

Yurewicz, D.A.; Advocate, D.M.; Sequeira, J.J.; McDermott, V.J.; Young, R.H.; Wellman, P.C. [Exxon Exploration Co., Houston, TX (United States)] [and others

1996-08-01

229

Red Sea hydrocarbon system focus on the source rock and hydrocarbon generation  

Energy Technology Data Exchange (ETDEWEB)

Potential source rocks were identified in the Egyptian Red Sea wells. These are Middle-Late Miocene and/or Early Miocene. The former contains up to 7.0% total organic carbon (TOC) and kerogen type is I and II. TOC values in the later up to 1.0% and kerogen type is II-III. Source rocks maturity, determined mainly by vitrinite reflectance and Tmax, reveals that the studied sequences have a maturity range from marginally mature to mature and over mature only were they are affected by abrupt change associated with thermal anomaly. Vitrinite reflectance pilots, revealed two thermal events affecting the maturity. The first event is Pre-intra-Rudeis unconformity, with a gradient of 0.26 to 0.66 % R[sub o] per 1,000 feet of burial. The later event occurred at the Post intra-Rudeis unconformity with a gradient of 0.02 to 0.06 % Ro increase per 1,000 feet. As a result of tectonism and the variation in the temperature gradients, the present top oil window varies in depth from 1540 to 3505 m and the hydrocarbon generation modeling suggests that, the generation may have occured during Late Miocene time and is still going on. Rock-Eval analysis indicates that there is ample evidence of hydrocarbon migration in the region.

Tammam, M.T. (Egyptian General Petroleum Corp., Cairo (Egypt))

1996-01-01

230

Red Sea hydrocarbon system focus on the source rock and hydrocarbon generation  

Energy Technology Data Exchange (ETDEWEB)

Potential source rocks were identified in the Egyptian Red Sea wells. These are Middle-Late Miocene and/or Early Miocene. The former contains up to 7.0% total organic carbon (TOC) and kerogen type is I and II. TOC values in the later up to 1.0% and kerogen type is II-III. Source rocks maturity, determined mainly by vitrinite reflectance and Tmax, reveals that the studied sequences have a maturity range from marginally mature to mature and over mature only were they are affected by abrupt change associated with thermal anomaly. Vitrinite reflectance pilots, revealed two thermal events affecting the maturity. The first event is Pre-intra-Rudeis unconformity, with a gradient of 0.26 to 0.66 % R{sub o} per 1,000 feet of burial. The later event occurred at the Post intra-Rudeis unconformity with a gradient of 0.02 to 0.06 % Ro increase per 1,000 feet. As a result of tectonism and the variation in the temperature gradients, the present top oil window varies in depth from 1540 to 3505 m and the hydrocarbon generation modeling suggests that, the generation may have occured during Late Miocene time and is still going on. Rock-Eval analysis indicates that there is ample evidence of hydrocarbon migration in the region.

Tammam, M.T. [Egyptian General Petroleum Corp., Cairo (Egypt)

1996-12-31

231

PROCESS FOR PREPARING A HYDROCARBON OR MIXTURE OF HYDROCARBONS  

UK PubMed Central (United Kingdom)

A process for preparing a hydrocarbon or mixture of hydrocarbons comprising the steps of (i) hydrogenating furfural, 5-hydroxymethylfurfural or a mixture of furfural and 5-hydroxymethylfurfural to provide furfuryl alcohol, 2,5-furandimethanol or a mixture of furfuryl alcohol and 2,5-furandimethanol (ii) oligomerizing the alcohol or mixture of alcohols of step (i) in the presence of an acidic catalyst to provide a carbon-carbon coupled oligomer and (iii) hydrogenating the oligomer of step (ii) is provided. The hydrocarbons are useful as fuel blending components. Processes for controlling the oligomerization of alcohol or mixture of alcohols to optimise the production of oligomers suitable for conversion to hydrocarbons useful as kerosene and diesel components are also provided.

VAN BUIJTENEN JEROEN; LANGE JEAN-PAUL; PRICE RICHARD JOHN

232

International Migration and Human Rights  

Science.gov (United States)

The Global Migration Group (GMG) is an inter-agency group that is dedicated to encouraging the "adoption of more coherent, comprehensive and better coordinated approaches to the issue of international migration." Their number includes representatives from UNICEF, the World Bank and various regional commissions from the United Nations. In October 2008, they released this 144-page report in order to commemorate and reflect on the 60th anniversary of the Universal Declaration of Human Rights. The report is divided into seven sections, including those dealing with the legal framework of migration, globalization and migration trends, migration data, and a concluding chapter which discusses some of the most pressing issues facing different migrant groups around the world. The report also includes three very useful appendices which deal with the policy instruments used in regards to human migration and the adoption of key United Nations legal instruments involved with international migration.

233

Origin and significance of redistributional secondary porosity  

Energy Technology Data Exchange (ETDEWEB)

The post-depositional leaching of feldspars, rock fragments and carbonate cements to give secondary porosity is an extremely widespread feature of clastic rocks. The presence of corroded grains, corroded carbonate cements and oversized pores suggests that aggressive fluids have caused the complete or partial dissolution of minerals. This in turn has led to the idea that all secondary porosity is responsible for the creation of additional porosity. This porosity enhancement is thought to lead to the development of potential hydrocarbon reservoirs in sequences that would otherwise not contain them. However, interpreting the significance of secondary porosity poses a major perceptual problem to petrographers. Almost all sandstones contain secondary porosity, but some appear to contain nothing but secondary porosity. In these circumstances it is all too easy to arrive at the interpretation that the porosity would be very low in the absence of leached porosity. Many petrographers do not test this contention, instead they are content 'to believe the evidence of their own eyes'. It is the purpose of this paper to examine the petrographic significance of secondary porosity and explain its almost ubiquitous presence. (author).

Giles, M.R.; Boer, R.B. de (Koninklijke/Shell Exploratie en Produktie Lab., Rijswijk (NL))

1990-11-01

234

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.

2007-01-01

235

Geochemical ways of artificial radionuclide migration in biosphere  

International Nuclear Information System (INIS)

This collection presents abstracts of papers on the following subjects: organization and methodology of research and developments on creation of combined medium- and largescale landscape-geochemical and radioecological maps for territories contaminated by radionuclides; typological and space features of distribution of artificial radionuclides and regularities of their migration, the radionuclides being entered the biosphere during accidents at NPPs; forms of artificial radionuclides in biosphere after the NPP accidents; simulation of primary entering and secondary migration of radionuclides in biosphere; methodology of organization and conducting radiogeochemical monitoring of biosphere; new methods and means for radiation monitoring of the environment.

1991-01-01

236

Tectonothermal modeling of hydrocarbon maturation, Central Maracaibo Basin, Venezuela  

Energy Technology Data Exchange (ETDEWEB)

The petroliferous Maracaibo Basin of northwestern Venezuela and extreme eastern Colombia has evolved through a complex geologic history. Deciphering the tectonic and thermal evolution is essential in the prediction of hydrocarbon maturation (timing) within the basin. Individual wells in two areas of the central basin, Blocks III and V, have been modeled to predict timing of hydrocarbon generation within the source Upper Cretaceous La Luna Formation, as well as within interbedded shales of the Lower-Middle Eocene Misoa Formation reservoir sandstones. Tectonic evolution, including burial and uplift (erosional) history, has been constrained with available well data. The initial extensional thermal regime of the basin has been approximated with a Mackenzie-type thermal model, and the following compressional stage of basin development by applying a foreland basin model. Corrected Bottom Hole Temperature (BHT) measurements; from wells in the central basin, along with thermal conductivity measurements of rock samples from the entire sedimentary sequence, resulted in the estimation of present day heat flow. An understanding of the basin`s heat flow, then, allowed extrapolation of geothermal gradients through time. The relation of geothermal gradients and overpressure within the Upper Cretaceous hydrocarbon-generating La Luna Formation and thick Colon Formation shales was also taken into account. Maturation modeling by both the conventional Time-Temperature Index (TTI) and kinetic Transformation Ratio (TR) methods predicts the timing of hydrocarbon maturation in the potential source units of these two wells. These modeling results are constrained by vitrinite reflectance and illite/smectite clay dehydration data, and show general agreement. These results also have importance regarding the timing of structural formation and hydrocarbon migration into Misoa reservoirs.

Manske, M.C. [OMNI Laboratories, Inc., Maracaibo (Venezuela)

1996-08-01

237

Subsurface fate of spilled petroleum hydrocarbons in continuous permafrost  

Science.gov (United States)

Accidental releases of approximately 2000 m3 of fuel have resulted in subsurface contamination adjacent to Imikpuk Lake, a drinking-water source near Barrow, AK. This paper presents a conceptual model of the distribution and transport of subsurface free-phase hydrocarbons at this site. The mean annual temperature in Barrow is -13 ??C, and average monthly temperatures exceed 0 ??C only during the months of June, July, and August. As a result, the region is underlain by areally continuous permafrost that extends to depths of up to 300 m and constrains subsurface hydrologic processes to a shallow zone that temporarily thaws each summer. During the 1993 and 1994 thaw seasons, the measured depth of thaw varied across the site from approximately 0.5 to 2 m. However, exploratory borings in 1995 showed that free-phase hydrocarbons were present at depths greater than 3 m, indicating that permafrost at this site is not a barrier to the vertical migration of nonaqueous-phase liquids. In 1996, a subsurface containment barrier was installed to prevent lateral movement of contaminated water to Imikpuk Lake, and a recovery trench was excavated upgradient of the barrier to facilitate removal of free-phase hydrocarbons. Free-phase hydrocarbons were recovered from the trench during 1996, 1997, and 1998. Recovery rates diminished over this time, and in 1999, no further product was recovered and the recovery operation was halted. Subsequent exploratory borings in 2001 and 2002 have revealed that some product remains in the subsurface. Data indicate that this remaining product exists in small discrete pockets or very thin layers of hydrocarbon floating on brine. These small reservoirs appear to be isolated from one another by relatively impermeable permafrost. Published by Elsevier B.V.

McCarthy, K.; Walker, L.; Vigoren, L.

2004-01-01

238

Bio energies: hydrocarbons bio treatments  

Energy Technology Data Exchange (ETDEWEB)

Pollution by hydrocarbons is consecutive to human activity. Except accidental pollutions, the contamination of sea comes from 'wild' degassing and International community tries to get rid of it.

Anon.

1994-03-01

239

Hydrocarbon stability under thermal stress  

Energy Technology Data Exchange (ETDEWEB)

Two aspects of the thermal stability of hydrocarbons are of particulra interest: (1) the possibility of cracking of hydrocarbons under high thermal stress; and (3) the formation of gas. The cracking of hydrocarbons in the reservoir has long been a controversial topic, generally with no scientific evidence either for or against the hypothesis. The issue is addressed here through analysis of the biomarkers, where the expected product slate is identified through experiment. Extracts of moderate and high maturity natural samples, both source rock and coals, are then examined for evidence of thermal alteration of biomarkers. Appropriate geology background is presented to ensure the accuracy of the maturity determinations. The formation of gas, particularly methane, has long been a puzzle to organic geochemists. Conventional widsom has suggested that oil cracks completely to methane, but lab experiments of the thermolysis of model hydrocarbons have shown that the dominant products are propane and butane. A new mechanism is presented which is highly selective for methane.

McNeil, R.I.; BeMent, W.O.

1995-12-01

240

Predicting hydrocarbon release from soil  

International Nuclear Information System (INIS)

'Full text:' The remediation of hazardous chemicals from soils can be a lengthy and costly process. As a result, recent regulatory initiatives have focused on risk-based corrective action (RBCA) approaches. Such approaches attempt to identify the amount of chemical that can be left at a site with contaminated soil and still be protective of human health and the environment. For hydrocarbons in soils to pose risk to human heath and the environment, the hydrocarbons must be released from the soil and accessible to microorganisms, earthworms, or other higher level organisms. The sorption of hydrocarbons to soil can reduce the availability of the hydrocarbon to receptors. Typically in soils and sediments, there is an initial fast release of a hydrocarbon from the soil to the aqueous phase followed by a slower release of the remaining hydrocarbon to the aqueous phase. The rate and extent of slow release can influence aqueous hydrocarbon concentrations and the fate and transport of hydrocarbons in the subsurface. Once the fast fraction of the chemical has been removed from the soil, the remaining fraction of a chemical may desorb at a rate that natural mechanisms can attenuate the released hydrocarbon. Hence, active remediation may be needed only until the fast fraction has been removed. However, the fast fraction is a soil and chemical specific parameter. This presentation will present a tier I type protocol that has been developed to quickly estimate the fraction of hydrocarbons that are readily released from the soil matrix to the aqueous phase. Previous research in our laboratory and elsewhere has used long-term desorption (four months) studies to determine the readily released fraction. This research shows that a single short-term (less than two weeks) batch extraction procedure provides a good estimate of the fast released fraction derived from long-term experiments. This procedure can be used as a tool to rapidly evaluate the release and bioavailability of hydrocarbons in a contaminated soil. This knowledge can enhance the selection and determine the duration of a proper remediation strategy. Information will be provided on the correlation of the results from this protocol to the results of chemical loss in contaminated soil bioremediation systems. This research has been completed, the data is currently being analyzed and the results will be fully evaluated by early 2002. As a result, the protocol and potential applications to field decisions will be presented and discussed. (author)

2002-01-01

 
 
 
 
241

Secondary seed dispersal and its role in landscape organization  

Science.gov (United States)

Mathematical models of banded vegetation patterns predict rapid upslope migration of vegetated patches not realized in field observations, a key point of disagreement between theory and observation. It is shown that the disagreement between model results and field observations can arise from seed dispersal dynamics. Two representations of biomass movement are used to test the hypothesis that secondary seed dispersal in overland flow inhibits band migration. The first is based on coupling down-slope water transport and seed advection. The second uses a kernel-based representation of seed transport where an anisotropic dispersal kernel combines the effects of isotropic primary and downslope secondary seed dispersal, and ensures that conclusions about secondary dispersal are independent of diffusive representations of biomass movement. The analysis demonstrates that secondary seed dispersal can retard upward movement of banded vegetation irrespective of the precise representation of biomass movement as long as the anisotropic effects are accounted for.

Thompson, Sally; Katul, Gabriel

2009-01-01

242

Process for secondary recovery  

Energy Technology Data Exchange (ETDEWEB)

Hydrocarbons are recovered from a subterranean hydrocarbon-bearing formation penetrated by an injection well and a production well by displacing hydrocarbons toward the production well using a drive fluid such as water thickened with a copolymer of acrylamide and vinyl sulfonic acid or salts thereof or with a copolymer of acrylamide and styrene sulfonic acid or salts thereof as well as these same copolymers alkoxylated with an alkylene oxide. Optionally, the drive fluid can be saturated with carbon dioxide, nitrogen, natural gas or mixtures of these gases.

Hunter, W.D.

1983-09-27

243

A hydrocarbon fire test method  

Energy Technology Data Exchange (ETDEWEB)

The activity within the oil and gas industry, offshore and onshore, led to the fact that a standardized test method simulating a real hydrocarbon fire ought to be established. Research work has been performed with the aim of developing a relevant hydrocarbon fire test method. The report presents results from corresponding research work in United States, United Kingdom and Norway as a basis for the proposed test method. 5 figs., 2 tabs., 19 refs. (Author).

Landroe, H.

1985-03-01

244

Method for producing hydrocarbon mixtures  

Energy Technology Data Exchange (ETDEWEB)

Mixtures of saturated or unsaturated C/sub 2/-C/sub 5/ hydrocarbons are produced by aerobically cultivating a microorganism belonging to a wide variety of general fungi, yeasts, bacteria and actinomycetes in a water-containing medium, and recovering the hydrocarbon mixtures from the liquid phase and/or gaseous ambience of the medium. Industrial wastes and various biomass can be employed as nutrient sources in the cultivation.

Fukuda, H.; Takahira, O.; Takao, F.

1989-02-07

245

Bioassay of polycyclic aromatic hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

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.

Van Kirk, E.A.

1980-08-01

246

Migration and sensory changes of packaging materials caused by ionising radiation  

Energy Technology Data Exchange (ETDEWEB)

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.

Welle, Frank E-mail: fw@ivv.fhg.de; Mauer, Alexandra; Franz, Roland

2002-03-01

247

Hydrocarbon prospectivity of the Argentine Continental Slope  

Energy Technology Data Exchange (ETDEWEB)

A rift basin containing stratigraphic and structural closures is developed along the Argentine slope over a distance of some 1000 km and area of 50,000 km[sup 2] in potentially exploitable water depths of 200 to 1500 m. No wells exist on this part of the continental margin. Rifting began during the Late Triassic/Jurassic and ended in Early Cretaceous. The first marine seaways flooded the Rift alluvial plains and lake. In Hauterian-Barrenian time, low circulation marine conditions with oxygen deficiency prevailed up to Rio Grande/Walvis Ridge flooding in part the coastal pull-apart basins. A major marine transgression in the Maastrichtian formed a widespread seal over the entire shelf and slope area. Four play types were identified: (1) a major north-east trending elongate delta system sourced inland from the San Julien (N. Malvinas) Basin and deposited on the southern Patagonian shelf and rise, (2) reworked deltaic barrier sands accumulated along the crest of the Outer Basement Ridge, (3) The Outer Basement Ridge, a major structural closure 400 km long, and (4) a series of margin-parallel rift systems in the offshore region between the 200 m and 1500 m isobaths. Regional seismic data and geological correlations suggest that oil prone source rocks are likely in the Middle and Upper Jurassic and Cretaceous formations. Source rocks are probably mature east and west of the Outer Basement Ridge and in the easterndepocenter of the Colorado Basin. Eastward migration from Jurassic age lacustrine source rocks in the Colorado Basin may have charged traps along the crest of the Outer Basement Ridge. Westward directed migration from deeply buried Aptian age marine source rocks in the Atlantic basins has probably charged prospective stratigraphic and structural traps in a suite of coast-parallel grabens developed on the Argentine continental shelf and slope. The Argentine offshore region, therefore, offers significant encouragement as a productive hydrocarbon province.

Light, M.P.R.; Keeley M.L.; Maslanyj, M.P.; Urien, C.M.; Hoggs, S.L.

1993-02-01

248

HYDROCARBONS RESERVES IN VENEZUELA  

Energy Technology Data Exchange (ETDEWEB)

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)

Gonzalez Cruz, D.J.

2007-07-01

249

Hydrocarbon potential of Morocco  

Energy Technology Data Exchange (ETDEWEB)

Morocco lies at the junction of the African and Eurasian plates and carries a record of their movements since the end of the Precambrian. Four structural regions with basins and troughs can be identified: Saharan (Tarfaya-Ayoun and Tindouf basins); Anti-Atlas (Souss and Ouarzazate troughs and Boudnib basin); the Essaouria, Doukkala, Tadla, Missour, High Plateau, and Guercif basins; and Meseta and Rif (Rharb and Pre-Rif basins). The targets in the Tindouf basin are Paleozoic, Cambrian, Ordovician (clastics), Devonian (limestones), and Carboniferous reservoirs sourced primarily by Silurian shales. In the remaining basins, excluding the Rharb, the reservoirs are Triassic detritals, limestones at the base of the Lias and Dogger, Malm detritals, and sandy horizons in the Cretaceous. In addition to the Silurian, potential source rocks include the Carboniferous and Permo-Carboniferous shales and clays; Jurassic shales, marls, and carbonates; and Cretaceous clays. In the Rharb basin, the objectives are sand lenses within the Miocene marls. The maturation level of the organic matter generally corresponds to oil and gas. The traps are stratigraphic (lenses and reefs) and structural (horsts and folds). The seals in the pre-Jurassic rocks are shales and evaporites; in the younger rocks, shales and marl. Hydrocarbon accumulations have been found in Paleozoic, Triassic, Liassic, Malm, and Miocene rocks.

Achnin, H.; Nairn, A.E.M.

1988-08-01

250

Evaluation of hydrocarbon potential  

Energy Technology Data Exchange (ETDEWEB)

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.

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

1992-09-30

251

Towards an understanding of the role of clay minerals in crude oil formation, migration and accumulation  

Science.gov (United States)

This article reviews progress in the understanding of the role of clay minerals in crude oil formation, migration and accumulation. Clay minerals are involved in the formation of kerogen, catalytic cracking of kerogen into petroleum hydrocarbon, the migration of crude oil, and the continued change to hydrocarbon composition in underground petroleum reservoirs. In kerogen formation, clay minerals act as catalysts and sorbents to immobilize organic matter through ligand exchange, hydrophobic interactions and cation bridges by the mechanisms of Maillard reactions, polyphenol theory, selective preservation and sorptive protection. Clay minerals also serve as catalysts in acid-catalyzed cracking of kerogen into petroleum hydrocarbon through Lewis and Brønsted acid sites on the clay surface. The amount and type of clay mineral affect the composition of the petroleum. Brønsted acidity of clay minerals is affected by the presence and state of interlayer water, and displacement of this water is a probable driver in crude oil migration from source rocks. During crude oil migration and accumulation in reservoirs, the composition of petroleum is continually modified by interaction with clay minerals. The clays continue to function as sorbents and catalysts even while they are being transformed by diagenetic processes. The detail of chemical interactions and reaction mechanisms between clay minerals and crude oil formation remains to be fully explained but promises to provide insights with broader application, including catalytic conversion of biomass as a source of sustainable energy into the future.

Wu, Lin Mei; Zhou, Chun Hui; Keeling, John; Tong, Dong Shen; Yu, Wei Hua

2012-12-01

252

Residential Mobility and Migration  

Science.gov (United States)

This activity is used in an Introduction to Populations Issues class for undergraduate students. This activity looks at education, marital status, age and race to explore migration trends in the United States. This activity uses eight customized data sets made from the 1990 census. It guides students through data manipulation using WebCHIP software found at DataCounts!. To open WebCHIP with the dataset for the activity, please see instructions and links in the exercise documents under teaching materials. For more information on how to use WebCHIP, see the How To section on DataCounts!

Crowder, Kyle

253

Issues of Labor Migration  

Directory of Open Access Journals (Sweden)

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.

Liliana Gheorghe

2010-01-01

254

Low severity hydrocarbon steam reforming process  

Energy Technology Data Exchange (ETDEWEB)

A process is described for producing ammonia which comprises: (a) primary catalytically reforming at super atmospheric pressure in a direct-fired primary reforming zone, a hydrocarbon feedstock with steam to produce a gas containing carbon oxides, hydrogen and methane; (b) secondary catalytically reforming the gas from step (a) by introducing air and bringing the mixture towards equilibrium thereby producing a secondary reformer effluent gas containing nitrogen, carbon oxides, hydrogen and a decreased quantity of methane; (c) converting carbon monoxide catalytically with steam to carbon dioxide and hydrogen; (d) removing carbon oxides to give an ammonia synthesis gas comprising nitrogen and hydrogen and compressing the gas to ammonia synthesis pressure; (e) reacting the synthesis gas in an ammonia synthesis zone to produce ammonia and recovering ammonia from the reacted gas to produce an ammonia-depleted gas stream; (f) recycling at least a portion of the ammonia-depleted gas stream to the ammonia synthesis zone; and (g) treating a sidestream of the ammonia-depleted gas to separate a stream enriched in hydrogen and an inerts-enriched gas stream, and returning the enriched hydrogen stream to the ammonia synthesis zone.

Osman, R.M.; Byington, R.G.

1986-06-03

255

Ontogenetic, reproductive, and nutritional effects on the cuticular hydrocarbons of host-specific ectoparasitoid Cephalonomia tarsalis (Hymenoptera: bethylidae).  

UK PubMed Central (United Kingdom)

Cuticular hydrocarbons have been identified from adult males and females of the bethylid wasp Cephalonomia tarsalis (Ashmead). The 2 sexes possess the same cuticular hydrocarbons, but in different amounts and proportions. Hydrocarbon components identified include n-alkanes (C23-C37), 5-methyl alkanes (5-MeC25-5MeC29), 5,X-dimethyl alkanes (5,17-and 5,19-diMeC29 and 5,17- and 5,19-diMeC33), and a homologous series of Z-monones with double bonds at ?11, ?9, and ?7 (C25:1-C37:1). The n-alkanes and alkenes are the predominant components in all cases, the 5-methyl alkanes being only minor components. The dimethyl components are present in only trace amounts. Age, mating status, and, for females, host-feeding status, were examined for their effect on hydrocarbon quantities and proportions. Males showed little change in their hydrocarbon profiles, but females showed strong age, host feeding, and age x host feeding effects on total hydrocarbon quantities and on individual hydrocarbon components. Mating status did not affect female hydrocarbons. The silk cocoons from which the parasites emerged yielded the same cuticular hydrocarbon components as were found on the newly emerged male and female wasps, but n-alkanes were now the major components. Hydrocarbon profiles of female cocoons differed from male cocoon hydrocarbons primarily in the relative abundances of the monene isomers. Bioassays of male response to hexane extracts of female and male cocoons indicated that the male could differentiate between the two. The primary gender recognition cue is not the cocoon hydrocarbons, but rather a female-produced sex pheromone, the hydrocarbons serving as a secondary recognition cue.

Howard RW

1998-01-01

256

Nuclear mechanics during cell migration.  

Science.gov (United States)

During cell migration, the movement of the nucleus must be coordinated with the cytoskeletal dynamics at the leading edge and trailing end, and, as a result, undergoes complex changes in position and shape, which in turn affects cell polarity, shape, and migration efficiency. We here describe the steps of nuclear positioning and deformation during cell polarization and migration, focusing on migration through three-dimensional matrices. We discuss molecular components that govern nuclear shape and stiffness, and review how nuclear dynamics are connected to and controlled by the actin, tubulin and intermediate cytoskeleton-based migration machinery and how this regulation is altered in pathological conditions. Understanding the regulation of nuclear biomechanics has important implications for cell migration during tissue regeneration, immune defence and cancer. PMID:21109415

Friedl, Peter; Wolf, Katarina; Lammerding, Jan

2010-11-23

257

Nuclear mechanics during cell migration.  

UK PubMed Central (United Kingdom)

During cell migration, the movement of the nucleus must be coordinated with the cytoskeletal dynamics at the leading edge and trailing end, and, as a result, undergoes complex changes in position and shape, which in turn affects cell polarity, shape, and migration efficiency. We here describe the steps of nuclear positioning and deformation during cell polarization and migration, focusing on migration through three-dimensional matrices. We discuss molecular components that govern nuclear shape and stiffness, and review how nuclear dynamics are connected to and controlled by the actin, tubulin and intermediate cytoskeleton-based migration machinery and how this regulation is altered in pathological conditions. Understanding the regulation of nuclear biomechanics has important implications for cell migration during tissue regeneration, immune defence and cancer.

Friedl P; Wolf K; Lammerding J

2011-02-01

258

The challenges of managing migration  

Energy Technology Data Exchange (ETDEWEB)

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.

Tacoli, Cecilia

2005-10-15

259

Humics and radionuclide migration  

Energy Technology Data Exchange (ETDEWEB)

Humic materials occur throughout the ecosphere in soils and waters, even in deep anoxic underground systems. The spectrum of molecula weights, the nature of the carbon skeleton and the types, positions and relative numbers of functional groups vary widely, in part depending on the origin and age of the humic material. Acid-base titration, C-13 CP/MAS solid-state nuclear magnetic resonance and ultrafiltration serve to define major operational characteristics of these materials. Humic materials sorb to surfaces and particulate matter in waters and can form colloids themselves. The structures and other general properties of humic substances are discussed briefly. Of importance in the migration of radionuclides in geological media is the strong complexing and redox interactions of humic materials to metal ions. The polyelectrolyte nature of humic molecules leads to very strong complexing which increases in strength with the increasing degree of ionization of the carboxylate groups. In addition, metal ions can be reduced to lower states; e.g., Pu(VI) to Pu(IV). Some unique problems are encountered in measuring the metal binding and/or redox by humic materials. However, such data is important as humic material can have significant effects on metal ion speciation and behavior in geologic systems even at 0.1 ppm levels. Measurements of actinide-humate interactions and their possible consequences on actinide migration are reviewed.

Choppin, G.R.

1988-01-01

260

Moisture migration in shale  

Energy Technology Data Exchange (ETDEWEB)

The paper evaluates problems associated with mechanical and physical properties of carboniferous rock strata, particularly shales. Effects of moisture content on mechanical shale properties and its deformation under influence of rock strata stress are analysed. Shale porosity is extremely low and shales are practically impermeable to water. Diffusion is the most probable way of moisture penetration into shales. Capacity for moisture migration in shales is determined by diffusion coefficient. The results of laboratory investigations into moisture diffusion in shales are evaluated. Cylindrical shale samples were exposed to atmospheric air with humidity content ranging from 12% to 100%. Investigations show that moisture diffusion of shale samples depends on the relative humidity. This dependence has a linear character. A diffusion equation is used for determining the rate of moisture migration into a flat roof of a working in a coal mine. Investigations show that flow of mine air with a high relative humidity does not increase moisture content in the roof consisting of shales and does not change shale mechanical properties. However, shales are influenced indirectly by air humidity which causes shale cracking and fracturing. (7 refs.) (In English)

Ryncarz, T.

1982-01-01

 
 
 
 
261

Forced Migration Review  

Science.gov (United States)

Published tri-annually since January 1998, the Forced Migration Review (FMR) is the in-house journal of the Refugee Studies Centre at the University of Oxford. The journal (and its online edition made available on this site) is published in English, Arabic, and Spanish, and "provides the humanitarian community with a practice-oriented forum for debate on issues facing refugees and internally displaced people in order to improve policy and practice." From the site, visitors can browse through single articles or complete issues of the journal all the way back to 1998. Many of the issues are dedicated to a single theme, including recent issues which have been titled When does internal displacement end? and Reproductive health for displaced people: Investing in the future. The site also provides ample information on submitting articles to the journal, material on the current editorial board, and the themes for upcoming issues. Rounding out the site is a collection of related links for consideration, organized into topics such as international law, reproductive health and forced migration research institutes and centers.

262

Underground radionuclide migration  

International Nuclear Information System (INIS)

The number 9 sub-report of the safety assesment studies of the disposal of radioactive waste in rock-salt formations concerns the calculation of radio-nuclide migration with groundwater. Calculations ar carried out in two phases. The first phase consists of calculation of the groundwater flow system under a great number of different hydrological boundary conditions, which possibly can be encountered in future. Variations in sea level and consequences of glaciations are included. Given a great number of possible groundwater flow systems, in the second phase radionuclide migration is calculated for a restricted number of representative situations. Transport of radionuclides with groundwater takes place, starting at a release point at the top (edge) of the rock salt formation until the landsurface, the bottom of a sea or an extraction-well for public water supply has been reached, at which places concentrations radionuclides have been computed as a function of time. Calculations continued till all concentrations had reached their maxima. Results form the input for biosphere dose-calculations, as reported in the number 10 sub-report. (author). 26 refs.; 43 figs.; 22 tabs

1989-01-01

263

Secondary recovery process  

Energy Technology Data Exchange (ETDEWEB)

Hydrocarbons are recovered from a subterranean hydrocarbonbearing formation penetrated by an injection well and a production well by displacing hydrocarbons toward the production well using a drive fluid such as water thickened with a polymer comprising repeating units of vinyl sulfonic acid alkoxylated with 2,3-epoxy-1-propanol. Optionally, the drive fluid can be saturated with carbon dioxide and/or natural gas at the injection pressure.

Hunter, W. D.

1980-08-12

264

Secondary recovery process  

Energy Technology Data Exchange (ETDEWEB)

Hydrocarbons are recovered from a subterranean hydrocarbonbearing formation penetrated by an injection well and a production well by displacing hydrocarbons toward the production well using a drive fluid such as water thickened with a copolymer of acrylamide and vinyl sulfonic acid or salts thereof alkoxylated with 2,3-epoxy-1-propanol. Optionally, the drive fluid can be saturated with carbon dioxide and/or natural gas at the injection pressure.

Hunter, W.D.

1980-10-14

265

Europe: Migration and Development  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish 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 migración 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 (more) 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 redistribution 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 (more) 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.

Nigel, Harris

2006-06-01

266

Experimental glomerulonephritis induced by hydrocarbon exposure: A systematic review  

Directory of Open Access Journals (Sweden)

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.

Ravnskov Uffe

2005-01-01

267

3-D AVO and migration  

Energy Technology Data Exchange (ETDEWEB)

AVO is now being used in combined stratigraphic structural areas like the North Sea. As a result, migration is being used in conjunction with AVO. Tests were carried out using a relatively unstructured data set to study the effects of different migration methods to determine which are suitable for AVO. In this set, the differences between the migrated and unmigrated data were minimal, so any significant differences in AVO could only be due to the amplitude preserving effects of the migrations. Results were compared to AVO derived from NMO ONLY gathers which show good correlation to well control. Shorncliffe 3-D and Crowfoot 3-D were the two data volumes meeting the criteria for the tests. For the Shorncliffe 3-D, time slices of stacks showed little difference between the migrations. However, the AVO gradients showed significant differences. The common offset migration (COM) gradient displayed the channel better than the NMO ONLY gradient. For the Crowfoot 3-D, horizon slices showed small differences depending on which PSI (pre-stack interpolation)-migration-AVO flow was used. Better AVO attributes were obtained after COM (common offset migration) pre-stack time migration. 11 refs., 4 figs.

Gray, D. [Veritas GeoServices Ltd., (Canada); Chen, T.; Goodway, B. [PanCanadian Petroleum Ltd., Calgary, AB (Canada)

1998-09-01

268

Graphical approach to determination of hydrocarbon maturation in overthrust terrains  

Energy Technology Data Exchange (ETDEWEB)

With current exploration efforts in areas of overthrust tectonics, it is important to evaluate efficiently and effectively the effects of thrust-related thermal perturbations on hydrocarbon maturation. A simple graphical technique that combines Lopatin diagrams with thermal models for thrusting allows the explorationist to develop relatively detailed models for the timing of hydrocarbon maturation in overthrust terrains. By superimposing the appropriate geothermal gradients on the Lopatin diagram for a given sedimentary unit, the theoretical vitrinite reflectance can be calculated at any point along the burial history of that sediment. It is critical in these models to modify the geothermal gradients used in the Lopatin diagrams according to the perturbations in the normal gradient caused by the thermal effects of thrust faulting. The thermal effects due to thrusting can be quite pronounced. The graphical approach developed here is applicable not only to cases of simple overthrusting, but can also be modified to include the effects of multiple thrusting events, subsurface thrust planes, and post-thrust erosion. All of these models can provide critical constraints on the timing of maturation and migration as well as information on the degree of maturity of potential source rocks. Integration of maturation data generated from the Lopatin diagrams with the structural history of the region can help predict prior to drilling whether a prospective structure may contain hydrocarbons or if it is more likely to be a dry hole.

Furlong, K.; Edman, J.D.

1983-03-01

269

Paleotopography and hydrocarbon accumulation: Williston, Powder River, and Denver basins  

Energy Technology Data Exchange (ETDEWEB)

Recent geomorphic analyses of 1:24,000 scale topographic maps in the three major basins of the northern Great Plains have disclosed a persistent system of basement paleotopographic features that trend north-northeast throughout the region. Superimposed across this system and subtly influenced by it, are the northwesterly trending Laramide structural features. Paleozoic depositional patterns have been strongly influenced by the paleoridge and trough system formed by the north-northeast features. Mesozoic deposition has also been affected by the ancient subsurface system but in a more subtle manner. Many of the Paleozoic and Mezoxoic hydrocarbon locations in the three basins appear to be the results of paleotopographic control on hydrocarbon accumulation sites. This affect ranges from Paleozoic reef sites in the Williston basin through paleotrough localization of Pennsylvanian Minnelusa production in the Powder River basin to fractured Cretaceous Niobrara production at the Silo field in the Denver basin. Basement paleotopography is the underlying factor in all deposition and subsequent hydrocarbon migration in any basin. As such, it should be considered a major factor in the exploration for oil and gas.

Thomas, G.E. (Thomas and Associates, Denver, CO (United States))

1991-06-01

270

Subduction zone earthquake as potential trigger of submarine hydrocarbon seepage  

Science.gov (United States)

Methane, a potent greenhouse gas, is abundant in marine sediments. Submarine seepage of methane-dominated hydrocarbons is heterogeneous in space and time, and mechanisms that can trigger episodic seep events are poorly understood. For example, critical gas pressures have been predicted to develop beneath impermeable sediments that bear gas hydrates, making them susceptible to mechanical failure and gas release. Gas hydrates often occur in seismically active regions, but the role of earthquakes as triggers of hydrocarbon seepage through gas-hydrate-bearing sediments has been only superficially addressed. Here we present geochemical analyses of sediment cores retrieved from the convergent margin off Pakistan. We find that a substantial increase in the upward flux of gas occurred within a few decades of a Mw 8.1 earthquake in 1945--the strongest earthquake reported for the Arabian Sea. Our seismic reflection data suggest that co-seismic shaking fractured gas-hydrate-bearing sediments, creating pathways for the free gas to migrate from a shallow reservoir within the gas hydrate stability zone into the water column. We conservatively estimate that 3.26×108mol of methane have been discharged from the seep site since the earthquake. We therefore suggest that hydrocarbon seepage triggered by earthquakes needs to be considered in local and global carbon budgets at active continental margins.

Fischer, David; Mogollón, José M.; Strasser, Michael; Pape, Thomas; Bohrmann, Gerhard; Fekete, Noemi; Spiess, Volkhard; Kasten, Sabine

2013-08-01

271

Light hydrocarbons in Red Sea brines and sediments  

Energy Technology Data Exchange (ETDEWEB)

Light hydrocarbon (C/sub 1/-C/sub 3/) concentrations in the water from four Red Sea brine basins (Atlantis II, Suakin, Nereus and Valdivia Deeps) and in sediment pore waters from two of these areas (Atlantis II and Suakin Deeps) are reported. The hydrocarbon gases in the Suakin Deep brine are apparently of biogenic origin as evidenced by C/sub 1//(C/sub 2/ + C/sub 3/) ratios of approx. 1000. Methane concentrations (6-8 ..mu..l/l) in Suakin Deep sediments are nearly equal to those in the brine, suggesting sedimentary interstitial waters may be the source of the brine and associated methane. The Atlantis II Deep has two brine layers with significantly different light hydrocarbon concentrations indicating separate sources. The upper brine gas seems to be of biogenic origin (C/sub 1//(C/sub 2/ + C/sub 3/) = approx. 1000), whereas the lower brine gas is apparently of thermogenic origin (C/sub 1//(C/sub 2/ + C/sub 3/) = approx. 50). The thermogenic gas resulting from thermal cracking of organic matter in the sedimentary column apparently migrates into the basin with the brine, whereas the biogenic gas is produced in situ or at the seawater-brine interface. Methane concentrations in Atlantis II interstitial waters underlying the lower brine are about one half brine concentrations; this difference possibly reflects the known temporal variations of hydrothermal activity in the basin.

Burke, R.A. Jr.; Brooks, J.M.; Sackett, W.M.

1981-05-01

272

Hydrocarbon prospectivity assessment of the Southern Pattani Trough, Gulf of Thailand  

Energy Technology Data Exchange (ETDEWEB)

The Pattani Trough is an elongate north to south basin in the Gulf of Thailand offshore area that developed from Oligocene times onward. Numerous hydrocarbon discoveries, mainly gas, have been made within the Tertiary stratigraphic section in areas adjacent to the depocenter of the basin, but only dry holes have been drilled on the extreme basin margins and flanking platform areas. The southern Pattani Trough represents a [open quotes]transition zone[close quotes] in terms of potential hydrocarbon prospectivity between the low potential/high exploration risk basin marginal areas, and the high potential/low exploration risk basin marginal area. The development of hydrocarbon accumulation potential within the southern Pattani Trough can be related to a number of major controlling factors. These include structure, which on a regional scale shows a marked influence of tectonic regime on depositional system development, and on a more local scale determines trap development; stratigraphy, which determines reservoir geometry and potential hydrocarbon source rock facies distribution; petrology, which exerts a major control on depth related reservoir quality; overpressure development, which controls local migration pathways for generated hydrocarbons, and locally provides very efficient trap seals; geochemical factors, related to potential source facies distribution, hydrocarbon type; and thermal maturation of the section. The above factors have been combined to define low-, medium-, and high-risk exploration [open quotes]play fairways[close quotes] within the prospectivity transition zone of the southern Pattani Trough.

Mountford, N. (Unocal Thailand Ltd., Bangkok (Thailand))

1994-07-01

273

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

1992-01-01

274

Education and the decision to migrate: an econometric analysis of migration in Venezuela.  

Science.gov (United States)

Interstate labor force migration in Venezuela was estimated for 3 groups of migrants classified by their own educational levels. Regional educational levels and education-specific average wages were included as explanatory variables in order to distinguish between the various effects of education on migration and to estimate differences in the response of educated and uneducated migrants to other explanatory variables. The basic model resembled that used in other econometric studies of migration; migration was assumed to be a function of a number of origin and destination state characteristics which were believed likely to represent costs and benefits of living in various states for most persons. Migration rates rather than absolute numbers were the dependent variable. Zellner's regression technique was employed, and appropriate F statistics were used to test the null hypothesis of equal response of migrants to each of the explanatory variables across educational levels. A substantial proportion of the variance in migration rates was explained for each level of education. The results showed that educated members of the labor force in Venezuela are more mobile and also that there are significant differences in the responses of educated and uneducated migrants to variables which reflect the costs and benefits of alternative locations. The educated were less deterred by increased distance and more responsive to wage rates in alternative locations. The educated appear to be more mobile because of their greater access to information and greater incentives to make additional investments in search of better opportunities. Both educated and uneducated migrants are attracted to more populated regions but the elasticity is almost twice as high for the educated. Educational opportunity was found to be an important locational advantage for those who already had attended secondary school. The less educated are less likely to move to states with high educational levels, perhaps because they fear job competition from the educated. Destination unemployment variables were not highly significant for the uneducated. Results of the study indicate that disaggregation of migration by educational levels is necessary for a clear understanding of the complex relationships involved. PMID:12339297

Levy, M B; Wadycki, W J

1974-03-01

275

Extraction of hydrocarbons from a hydrocarbon-bearing substrate  

Energy Technology Data Exchange (ETDEWEB)

Hydrocarbons are extracted from a hydrocarbon-bearing substrate, such as shale oil, bituminous coal or tar sand, in the absence of oxygen at high temperature by passing substrate particles through a number of successive zones in which the substrate is mixed with a solid heat-bearing medium, such as hot spent substrate, the mixture being maintained in a fluidized-bed condition. The liberated hydrocarbons are removed by passage of an inert stripping gas in cross-current flow with respect to the passage of the substrate particles, i.e., the stripping gas passes through the zones in parallel while the substrate passes through the zones in series. The average cross-sectional area of one or more of the zones subsequent to the first one is smaller than the average cross-sectional area of the preceding zones.

Darton, R.C.; Van Meurs, H.C.A.; Voetter, H.; Krishna, R.

1982-10-27

276

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

Energy Technology Data Exchange (ETDEWEB)

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)

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

277

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)

2001-01-01

278

K-constants: water in hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

Liquid-vapor equilibrium constants for water in hydrocarbon-rich streams are vital to successful design of processes used for drying hydrocarbons by distillation/sup 5/. Unfortunately available works generally ignore this part of the water-hydrocarbon system. Generally study has centered on the water-rich phase in equilibrium with the hydrocarbon-rich phase. Most experimental work provides data on solubility of hydrocarbons in water and of water in hydrocarbons without giving information on the equilibrium vapor. Furthermore, most liquid-vapor equilibrium measurement has been made only at the three-phase saturation pressure, P/sub 1/, along the isobar MRS.

Adler, S.B.; Lin, T.C.T.

1985-04-01

279

Endobronchial valve migration.  

UK PubMed Central (United Kingdom)

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.

Jenkins M; Vaughan P; Place D; Kornaszewska M

2011-11-01

280

Endobronchial valve migration.  

Science.gov (United States)

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

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

2011-03-23

 
 
 
 
281

Migration - utopia or myopia?  

Directory of Open Access Journals (Sweden)

Full Text Available Peter Osborne spent a sabbatical in northern America and was surprised that so many scientists and students stated that caribou migration was largely the result of mosquito pressure. He failed however to find any documented evidence of this claim although he was constantly confronted by the well known «facts» that mosquitoes had been observed to drive caribou crazy and even kill juveniles. The issue Osborne wishes to focus is that an experimentally unsubstantiated anthropomorphism appears to have become critical evidence in support of a theory. A recent article in Nature (393, 511-513, 1998) devoted to the uses of 'science in fiction' to stimulate thought and discussion about aspects of academia encouraged him to write the following comment in the form of a parody of ancient Greek dialogues.

Peter Osborne

1998-01-01

282

Migration and women's health.  

UK PubMed Central (United Kingdom)

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.

Adanu RM; Johnson TR

2009-08-01

283

Nightly Test system migration  

CERN Multimedia

The summer student program allows students to participate to the Cern adventure. They can follow several interesting lectures about particle science and participate to the experiment work. As a summer student, I had worked for LHCb experiment. LHCb uses a lot of software to analyze its data. All this software is organized in packages and projects. They are built and tested during the night using an automated system and the results are displayed on a web interface. Actually, LHCb is changing this system. It is looking for a replacement candidate. So I was charged to unify some internal interfaces to permit a swift migration. In this document, I will describe shortly the system used by LHCb, then I will explain what I have done in detail.

Win-Lime, Kevin

2013-01-01

284

Objectivity Data Migration  

CERN Multimedia

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.

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

2003-01-01

285

The brine migration test  

International Nuclear Information System (INIS)

The authors discuss a joint US/FRG nuclear waste repository simulation experiment performed at the Asse Salt Mine in the Federal Republic of Germany (FRG). The High Level Waste (HLW) disposal in boreholes was simulated by the simultaneous emplacement of electrical heaters and cobalt-60 sources at four individual test sites located in a special underground test room at the 800 m-level. In order to resolve the issues of rock mass/waste package interaction the temperature field, brine migration into the heater boreholes, borehole gas pressure and composition, and rock mass stresses and displacments were monitored during the test. In order to validate computer code predictions the acquired data were compared to calculational results. Corrosion speciments remained in the heater boreholes during the course of the experiment and were afterwards examined

1989-01-01

286

Migration mechanisms of radionuclides from a clay repository toward adjacent aquifers and the surface; Mecanismes de migration des radionucleides d'un stockage de dechets radioactifs dans l'argile vers la surface  

Energy Technology Data Exchange (ETDEWEB)

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)

Marsily, G. de; Goncalves, J.; Violette, S. [Paris-6 Univ., UMR Sisyphe, 75 (France); Castro, M.C. [Michigan Univ., Ann Arbor, MI (United States). Dept. of Geological Sciences

2002-10-01

287

Hydrocarbon lakes on Titan  

Science.gov (United States)

The Huygens Probe detected dendritic drainage-like features, methane clouds and a high surface relative humidity (˜50%) on Titan in the vicinity of its landing site [Tomasko, M.G., and 39 colleagues, 2005. Nature 438, 765-778; Niemann, H.B., and 17 colleagues, 2005. Nature 438, 779-784], suggesting sources of methane that replenish this gas against photo- and charged-particle chemical loss on short (10-100) million year timescales [Atreya, S.K., Adams, E.Y., Niemann, H.B., Demick-Montelara, J.E., Owen, T.C., Fulchignoni, M., Ferri, F., Wilson, E.H., 2006. Planet. Space Sci. In press]. On the other hand, Cassini Orbiter remote sensing shows dry and even desert-like landscapes with dunes [Lorenz, R.D., and 39 colleagues, 2006a. Science 312, 724-727], some areas worked by fluvial erosion, but no large-scale bodies of liquid [Elachi, C., and 34 colleagues, 2005. Science 308, 970-974]. Either the atmospheric methane relative humidity is declining in a steady fashion over time, or the sources that maintain the relative humidity are geographically restricted, small, or hidden within the crust itself. In this paper we explore the hypothesis that the present-day methane relative humidity is maintained entirely by lakes that cover a small part of the surface area of Titan. We calculate the required minimum surface area coverage of such lakes, assess the stabilizing influence of ethane, and the implications for moist convection in the atmosphere. We show that, under Titan's surface conditions, methane evaporates rapidly enough that shorelines of any existing lakes could potentially migrate by several hundred m to tens of km per year, rates that could be detected by the Cassini orbiter. We furthermore show that the high relative humidity of methane in Titan's lower atmosphere could be maintained by evaporation from lakes covering only 0.002-0.02 of the whole surface.

Mitri, Giuseppe; Showman, Adam P.; Lunine, Jonathan I.; Lorenz, Ralph D.

2007-02-01

288

Software Engineering Challenges of Migration Projects  

Directory of Open Access Journals (Sweden)

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

S.Geetha; Dr.Alagaramy

2012-01-01

289

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

Science.gov (United States)

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. PMID:20869788

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

2010-09-25

290

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

UK PubMed Central (United Kingdom)

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.

Freitas JG; Mocanu MT; Zoby JL; Molson JW; Barker JF

2011-01-01

291

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

DEFF Research Database (Denmark)

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.

Skov, Christian; Aarestrup, Kim

2010-01-01

292

Modelling Turkish Migration to Germany  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This study develops a time series model of Turkish migration to Germany for the period 1963-2004 using the cointegration technique. A single cointegrating relation between the migration flow variable and the relative income ratio between Germany and Turkey, the unemployment rates in Germany and Turk...

Akkoyunlu, Sule; Siliverstovs, Boriss

293

Topic in Depth - Bird Migration  

Science.gov (United States)

The songs of spring are in the air when migrating birds grace the skies, making regular seasonal journeys in response to alterations in weather, habitat, and food availability. The following websites cover various aspects of the amazing and ancient phenomenon of bird migration.

2010-09-09

294

Potential East-West Migration  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Examines the migration potential in the Czech Republic, Hungary, Poland, & Slovakia, using 1996 survey data from 4,392 persons. Results indicate that all scenarios that predict an imminent exodus of people from East & Central Europe are exaggerating the real dimension of East-West migration. The mig...

Hintermann, Christiane; Fassmann, Heinz

295

Organic geochemistry and coal petrology of Tertiary brown coal in the Zhoujing mine, Baise Basin, South China; 3. Characteristics of polycyclic aromatic hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

The polycyclic aromatic hydrocarbons of the Tertiary brown coal from Zhoujing mine have been characterized in detail. They are composed mainly of aromatic sesqui-, di-, sester- and triterpenoid hydrocarbons, with retene and simonellite as the predominant species. Secondary in abundance are mono- to pentaaromatic triterpenoid hydrocarbons, derived from oleanane, ursane and lupane precursors, indicators of terrestrial sources. Minor species present are a tetraaromatic norhopane, undecyltoluene and perylene and most of the regular polynuclear aromatic hydrocarbons are found at trace levels only. 33 refs., 9 figs., 3 tabs.

Wang, T.-G.; Simoneit, B.R.T. (Jianghan Petroleum Institute, Shashi City (China). Petroleum Geochemistry Unit)

1991-07-01

296

Geology, source rocks and hydrocarbon generation in the Clarence-Moreton Basin. [Australia  

Energy Technology Data Exchange (ETDEWEB)

The geology and exploration history of the Triassic-Cretaceous Clarence-Moreton Basin are reviewed. Consideration of new geochemical data ('Rock-Eval', vitrinite reflectance, gas chromatography of extracts, organic carbon and elemental analysis of coals and kerogens) gives further insights into the hydrocarbon potential of the basin. Although organic-rich rocks are relatively abundant, most source rocks that have achieved the levels of maturation necessary for hydrocarbon generation are gas-prone. The exinite-rich oil-prone Walloon Coal Measures are in most parts relatively immature. Some restraints on migration pathways are evident and igneous and tectonic events may have disturbed potentially well-sealed traps. Further exploration is warranted, even though the basin appears gasprone and the overall prospects for hydrocarbons are only fair. The most promising areas seem to be west of Toowoomba for oil and the Clarence Syncline for gas.

Martin, A.R.; Saxby, J.D.

1982-05-01

297

Pre-Alleghenian (Pennsylvanian-Permian) hydrocarbon emplacement along Ordovician Knox unconformity, eastern Tennessee  

Energy Technology Data Exchange (ETDEWEB)

Cores taken during exploration for Mississippi Valley-type lead and zinc ores in the Mascot-Jefferson City zinc district of eastern Tennessee commonly contain hydrocarbon residues in carbonate rocks of the Knox Group immediately below the Lower Ordovician Knox unconformity. The location and number of these residue-bearing strata reveal information about the Paleozoic history of hydrocarbon emplacement in the region. Contour maps, generated from nearly 800 holes covering more than 20 km/sup 2/, indicate that zones with elevated organic content in the uppermost 30 m of the Lower Ordovician Mascot Dolomite show a strong spatial correlation with Middle Ordovician paleotopographic highs. These same zones show no spatial association with present-day structural highs, which were formed during Pennsylvanian-Permian Alleghenian tectonism. This suggests that the physical entrapment of hydrocarbons migrating through the upper permeable units of the Mascot must have occurred prior to the principal tectonism of the Alleghenian orogeny. 7 figures, 1 table.

Haynes, F.M.; Kesler, S.E.

1989-03-01

298

Enrichment of light hydrocarbon mixture  

Energy Technology Data Exchange (ETDEWEB)

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.

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

299

Enrichment of light hydrocarbon mixture  

Energy Technology Data Exchange (ETDEWEB)

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.

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

300

Absorbent to separate hydrocarbon gases  

Energy Technology Data Exchange (ETDEWEB)

The authors propose the use of the mixture of monohydric aliphatic alcohols as an absorbent to separate hydrocarbon gases. Its purpose is to reduce energy losses during the regenera tion of the absorbent. It is achieved by choosing a proper reagent which would change its absorptive power towards hydrocarbon gases. It is shown that the alcohol mixture possesses the maximum absorptive power towards hydrdocarbon gases at a pressure of 60 Kgf/cm/sup 2/ and at a temperature of 20 degrees. During the crystallization of alkohol mixture (10 degrees) the absorptive power decreases by 12.5. As the pressure drops from 60 to 10 kgf/cm/sup 2/ and the temperature simultaneously decreases to 10 degrees, the alkohol mixture does not contain any hydrocarbon gases. Special small-size plants have been used to study the economic efficiency of alkohol mixture. An example of determining absorptive power of an absorbent towards ethane and propane is given.

Stepanova, I.N.; Pluzhnikova, M.F.

1981-03-23

 
 
 
 
301

Secondary Controlled Swing Drive  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 co...

Pettersson, Karl

302

Facial motor neuron migration advances.  

UK PubMed Central (United Kingdom)

During development, the migration of specific neuronal subtypes is required for the correct establishment of neural circuits. In mice and zebrafish, facial branchiomotor (FBM) neurons undergo a tangential migration from rhombomere 4 caudally through the hindbrain. Recent advances in the field have capitalized on genetic studies in zebrafish and mouse, and high-resolution time-lapse imaging in zebrafish. Planar cell polarity signaling has emerged as a critical conserved factor in FBM neuron migration, functioning both within the neurons and their environment. In zebrafish, migration depends on specialized 'pioneer' neurons to lead follower FBM neurons through the hindbrain, and on interactions with structural components including pre-laid axon tracts and the basement membrane. Despite fundamental conservation, species-specific differences in migration mechanisms are being uncovered.

Wanner SJ; Saeger I; Guthrie S; Prince VE

2013-09-01

303

Gender perspective in migration studies  

Directory of Open Access Journals (Sweden)

Full Text Available Research field of migration has been developing for a long time parallel to and outside mainstream institutional academic sociology and its theoretical foundation. In the last two decades, within the field of migration studies, one specific aspect of the phenomena came to the research focus: gender, as significant factor that influences on motivation for migration, shaping, at the same time, its characteristics and specific experiences. With decisive breakthrough of qualitative methods in social sciences and humanities, as well as with gradual development of postmodern philosophy and feminist theory, gender migration studies have been established as research sub-discipline, with its own theoretical and categorical scientific apparatus (as well as institutional-academic grounding), managing more or less successfully to explain and understand multidimensional character of migration processes. This text represents an attempt to make relatively concise overview of disciplines’ historical, theoretical and research field development, as a first step in its broader affirmation within Serbian institutional sociology.

Peši? Jelena

2013-01-01

304

Biological enhancement of hydrocarbon extraction  

Energy Technology Data Exchange (ETDEWEB)

A method of microbial enhanced oil recovery for recovering oil from an oil-bearing rock formation is provided. The methodology uses a consortium of bacteria including a mixture of surfactant producing bacteria and non-surfactant enzyme producing bacteria which may release hydrocarbons from bitumen containing sands. The described bioprocess can work with existing petroleum recovery protocols. The consortium microorganisms are also useful for treatment of above oil sands, ground waste tailings, subsurface oil recovery, and similar materials to enhance remediation and/or recovery of additional hydrocarbons from the materials.

Brigmon, Robin L. (North Augusta, SC); Berry, Christopher J. (Aiken, SC)

2009-01-06

305

Origin and primary migration of oil and gas in the Huanghua depression  

Energy Technology Data Exchange (ETDEWEB)

The Huanghua depression is a Meso-Cenozoic basin. On the basis of geological and geochemical data, the threshold values proposed for oil generation in the basin is 2200 meters for depth and 90/sup 0/C for temperature, and for oil and gas maturation and expulsion 2600 meters and 101/sup 0/C. Four stages are presented for evolution of oil and gas: immature stage, sub-mature stage, mature stage and supermature stage. The defines of liquid state window are preliminarily established. Based on the relationship of changes of mudstone porosity, hydrocarbon conversion ratio and hydrocarbon expulsion curves with increasing depth, the author has analyzed the process of primary migration and pointed out that primary migration of oil and gas in this area occurred when the source rocks were buried at 2600 to 3400 meters. Predictions are made also for other areas with conditions unknown.

Tian, K.; Cao, Y.

1981-01-01

306

Iodine isothermal migration behaviour in titanium nitride  

International Nuclear Information System (INIS)

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 x 1015 cm-2. Thermal treatments were performed under secondary vacuum at temperatures ranging from 1200 to 1700 deg. 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 deg. 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 deg. C and Ea'=11.4±0.2eV above 1500 deg. C. Nitrogen evaporation from TiN surface under secondary vacuum was proposed as a contributing factor to the enhanced mobility of iodine at high temperature

2008-02-29

307

Transpiration Cooled Throat for Hydrocarbon Rocket Engines.  

Science.gov (United States)

This program's objective was to characterize the use of hydrocarbon fuels as transpiration coolants for rocket nozzle throats. The hydrocarbon fuels investigated in this program were RP-1 and methane. To adequately characterize the above transpiration coo...

L. May W. M. Burkhardt

1991-01-01

308

Total Petroleum Hydrocarbons (TPH): ToxFAQs  

Science.gov (United States)

... a state: This map displays locations where Total Petroleum Hydrocarbons (TPH) is known to be present. On ... can I get more information? ToxFAQs™ for Total Petroleum Hydrocarbons (TPH) ( Hidrocarburos Totales de Petróleo (TPH) ) August ...

309

Hydrocarbon-degrading sulfate-reducing bacteria in marine hydrocarbon seep sediments  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Microorganisms are key players in our biosphere because of their ability to degrade various organic compounds including a wide range of hydrocarbons. At marine hydrocarbon seeps, more than 90% of sulfate reduction (SR) is potentially coupled to non-methane hydrocarbon oxidation. Several hydrocarbon-...

Kleindienst, Sara

310

Simple rules guide dragonfly migration.  

UK PubMed Central (United Kingdom)

Every year billions of butterflies, dragonflies, moths and other insects migrate across continents, and considerable progress has been made in understanding population-level migratory phenomena. However, little is known about destinations and strategies of individual insects. We attached miniaturized radio transmitters (ca 300 mg) to the thoraxes of 14 individual dragonflies (common green darners, Anax junius) and followed them during their autumn migration for up to 12 days, using receiver-equipped Cessna airplanes and ground teams. Green darners exhibited distinct stopover and migration days. On average, they migrated every 2.9+/-0.3 days, and their average net advance was 58+/-11 km in 6.1+/-0.9 days (11.9+/-2.8 km d-1) in a generally southward direction (186+/-52 degrees). They migrated exclusively during the daytime, when wind speeds were less than 25 km h-1, regardless of wind direction, but only after two nights of successively lower temperatures (decrease of 2.1+/-0.6 degrees C in minimum temperature). The migratory patterns and apparent decision rules of green darners are strikingly similar to those proposed for songbirds, and may represent a general migration strategy for long-distance migration of organisms with high self-propelled flight speeds.

Wikelski M; Moskowitz D; Adelman JS; Cochran J; Wilcove DS; May ML

2006-09-01

311

Simple rules guide dragonfly migration.  

Science.gov (United States)

Every year billions of butterflies, dragonflies, moths and other insects migrate across continents, and considerable progress has been made in understanding population-level migratory phenomena. However, little is known about destinations and strategies of individual insects. We attached miniaturized radio transmitters (ca 300 mg) to the thoraxes of 14 individual dragonflies (common green darners, Anax junius) and followed them during their autumn migration for up to 12 days, using receiver-equipped Cessna airplanes and ground teams. Green darners exhibited distinct stopover and migration days. On average, they migrated every 2.9+/-0.3 days, and their average net advance was 58+/-11 km in 6.1+/-0.9 days (11.9+/-2.8 km d-1) in a generally southward direction (186+/-52 degrees). They migrated exclusively during the daytime, when wind speeds were less than 25 km h-1, regardless of wind direction, but only after two nights of successively lower temperatures (decrease of 2.1+/-0.6 degrees C in minimum temperature). The migratory patterns and apparent decision rules of green darners are strikingly similar to those proposed for songbirds, and may represent a general migration strategy for long-distance migration of organisms with high self-propelled flight speeds. PMID:17148394

Wikelski, Martin; Moskowitz, David; Adelman, James S; Cochran, Jim; Wilcove, David S; May, Michael L

2006-09-22

312

Hydrocarbon conversion process using a molten salt  

Energy Technology Data Exchange (ETDEWEB)

A method is described for conversion of methane to higher hydrocarbons. The method comprises contacting a hydrocarbon gas consisting of methane with a mixture comprising molten salt and at least one reducible metal oxide contact agent at a selected temperature within the range of about 500/sup 0/ to about 1000/sup 0/C to produce higher hydrocarbons and water.

Mazurek, H.

1987-05-12

313

Conversion of hydrocarbons using microwave radiation  

Energy Technology Data Exchange (ETDEWEB)

C[sub 1+] hydrocarbons can be effectively converted to primarily unsaturated hydrocarbon and hydrogen by subjecting the C[sub 1+] hydrocarbon to microwave radiation in the presence of water and at least one plasma initiator that is capable of initiating an electric discharge in an electromagnetic field. 6 figs.

Murphy, W.J.

1994-01-11

314

Process for secondary recovery  

Energy Technology Data Exchange (ETDEWEB)

Hydrocarbons are recovered from a subterranean hydrocarbonbearing formation penetrated by an injection well and a production well by displacing hydrocarbons toward the production well using a drive fluid such as water thickened with a copolymer of acrylamide and vinyl sulfonic acid or salts thereof or with a copolymer of acrylamide and styrene sulfonic acid or salts thereof as well as these same copolymers alkoxylated with an alkylene oxide. Optionally, the drive fluid can be saturated with carbon dioxide, nitrogen, natural gas or mixtures of these gases.

Hunter, W.D.

1982-08-10

315

Moisture migration in shale  

Energy Technology Data Exchange (ETDEWEB)

The moisture content of shales has a significant influence on their physical properties and behavior under the influence of forces. Their porosity is insignificant, and they are essentially impermeable for water, therefore the most likely method of water entering shale is diffusion. For mathematical description of the process of diffusion transfer of mass, the equation of mass flux, low of mass preservation, equation determining the concentration of moisture on the surface and equation describing the initial distribution of moisture are used. The solution for the diffusion coefficient was obtained on the condition of homogeneity and isotropy of shale. Laboratory experiments were also conducted on small cylindrical samples placed in the atmosphere with different moisture content. It was established that the coefficient of diffusion of moisture has almost a linear dependence on the air humidity. A calculation is made of the migration of moisture into the flat roofing of a shaft viewed as a one-dimensional process. The calculation for the particular case of the diffusion coefficient 2 x 10/sup -11/m/sup 2//sec indicated that wetting of the shale occurs very slowly.

Ryngarz, T.

1982-01-01

316

Planetary Migration to Large Radii  

CERN Multimedia

There is evidence for the existence of massive planets at orbital radii of several hundred AU from their parent stars where the timescale for planet formation by core accretion is longer than the disc lifetime. These planets could have formed close to their star and then migrated outwards. We consider how the transfer of angular momentum by viscous disc interactions from a massive inner planet could cause significant outward migration of a smaller outer planet. We find that it is in principle possible for planets to migrate to large radii. We note, however, a number of effects which may render the process somewhat problematic.

Martin, R G; Pringle, J E; Wyatt, M C

2007-01-01

317

Migration of traumatic intracranial subdural hematoma to lumbar spine causing radiculopathy.  

UK PubMed Central (United Kingdom)

BACKGROUND: There have been rare reports of intracranial subdural hematoma (SDH) that migrated into the spine. All previous cases have been surgically managed and in this case report, we describe the first case of conservatively managed spinal hematoma secondary to migratory intracranial SDH. CASE DESCRIPTION: A 26-year-old male presented with a left tentorial SDH after blunt trauma. He was conservatively managed and discharged home. He presented 8 days later with worsening lower back pain that was found to be secondary to a spinal SDH. CONCLUSION: Spinal hematomas can be a serious sequelae of migrated intracranial hematomas. Tentorial and other caudally located intracranial hematomas may be more prone to this phenomenon.

Li CH; Yew AY; Lu DC

2013-01-01

318

Diagenesis of hydrocarbon-bearing rocks in the Middle Ordovician Simpson Group, southeastern Anadarko Basin, Oklahoma  

Science.gov (United States)

Quartzarenites and subarkoses in the Middle Ordovician Simpson Group in the Gulf Costello No. 1 and Sunray-DX Parker No. 1 Mazur wells, southeastern Anadarko basin, have undergone a complex diagenetic and petroleum-migration history. During early burial, petroleum migrated locally through sandstones; patches of bitumen in calcite and bitumen-lined quartz overgrowths containing oil-bearing inclusions reflect the introduction of petroleum-bearing fluids at shallow depths. Stable-isotope data reveal that early calcite precipitated at near-surface temperatures from fluids dominated by marine carbon. At moderate to deep burial, calcite dissolution, followed by ferroan-dolomite and clay-mineral precipitation, occurred at about the same time as the rocks reached levels of thermal maturity sufficient for the generation of hydrocarbons. Maximum paleotemperatures during deep burial are estimated from maturation models to have reached 250°F in the Costello well and 300°F in the Mazur well. Maturation-derived temperatures in the Costello well are consistent with preliminary homogenization temperatures (210-250°F) for oil inclusions along microscopic healed fractures that formed during deep burial, thus supporting an Early to Middle Pennsylvanian timing for the generation and migration of late-stage hydrocarbons. The early petroleum phase, emplaced while the rocks were at shallow burial depths, migrated from mature source rocks deeper in the basin.

Pitman, Janet K.; Burruss, Robert C.

1989-01-01

319

Rotliegend red bed reservoirs: how important is organic maturation and migration?  

Energy Technology Data Exchange (ETDEWEB)

The interaction of organic maturation products and clastic reservoir rocks has mainly been studied with regard to petrophysical property evolution or metal-organic interactions. Compared to previous studies, we are focussing on integrated investigations of the mineralogical processes involved in the interaction of sandstones with organic maturation products. An improved understanding of the chemical interaction of red bed arkosic sandstones and hydrocarbons should enable the better assessment of whether such a clastic horizon has been subjected to hydrocarbon migration in the geological past or not. Neither organic traces are necessarily detectable after long burial and exposure to elevated temperatures nor do fluid inclusion studies reliably exhibit former hydrocarbon fluid contents in cements. However, the minor traces of authigenic minerals respectively distinctive petrographic features related to former presence of organic maturation products could be used as finger prints of past hydrocarbon migrations and allow tracing fluid flow paths in basin analytical work. This article gives an overview on the approaches and the present state of investigations. (orig.)

Schoener, R.; Gaupp, R. [Jena Univ. (Germany)

2003-07-01

320

Modeling the hydrocarbon systems of the North Viking Graben: A case study using a ray-tracing technique  

Energy Technology Data Exchange (ETDEWEB)

A 3-D model of the hydrocarbon system for the North Viking Graben was developed using IKU's SEMI software. The objectives of this study were to gain insights into the controls on hydrocarbon generation, expulsion, migration, and entrapment, and to use the results to aid in the ranking and risking of prospects. The study area contains several oil, gas, and condensate fields/discoveries at varying distances from the oil kitchen. The model covers an area approximately 100 km by 250 km. It contains 11 stratigraphic intervals from the seafloor down through the Middle Jurassic. Two source intervals were included: Upper Jurassic (Draupne) organic-rich shales and Middle Jurassic (Brent) coals. The carrier was taken to be Middle Jurassic (Brent) and Upper Jurassic (Sognefjord) sand-prone facies. Heat flow histories were modeled at selected well locations and extended to cover the study area. Kinetic models of oil and gas generation were used to model hydrocarbon generation. Hydrocarbon volumetrics considered trap capacity, expulsion efficiency, oil lost during migration, oil cracked to gas, gas dissolved in oil and leaked through the top seal of traps, and oil and gas spillage. The model was calibrated at the fields/discoveries in terms of known capacities and in-place reserves. Then the authors also examined the fill history of individual traps. The model was used to assess the migration risk associated with several prospects. They considered relative rather than absolute results.

Schroeder, F.W. (Exxon Production Research Co., Houston, TX (United States)); Sylta, O. (Continental Shelf and Petroleum Technology Research Institute, Trondheim (Norway))

1991-03-01

 
 
 
 
321

Process and apparatus for recovering hydrocarbons from air-hydrocarbon vapor mixtures  

Energy Technology Data Exchange (ETDEWEB)

A process and apparatus are disclosed for recovering hydrocarbons from an air-hydrocarbon vapor mixture such as the mixture of air and vaporized light hydrocarbon compounds expelled as a result of loading gasoline or the like into storage tanks, tank cars and tank trucks. The air-hydrocarbon vapor mixture is caused to flow through a bed of solid adsorbent whereby the hydrocarbons ar removed from the mixture and a residue gas stream comprised of substantially hydrocarbon-free air is produced. The substantialy hydrocarbon-free air is vented to the atmosphere and while the first bed is removing hydrocarbons from the air-hydrocarbon vapor mixture, a second bed of solid adsorbent having hydrocarbons adsorbed thereon is simultaneously regenerated by evacuating the bed with vacuum pumping and the air-hydrocarbon vapor mixture produced in the regeneration of the bed is contacted with a liquid absorbent whereby a major portion of the hydrocarbons are absorbed therefrom and recovered. The beds of solid adsorbent are cooled, at least while the air-hydrocarbon vapor mixture is flowing therethrough and hydrocarbons are being adsorbed on the bed, to prevent the beds from overheating due to side exothermic reactions of hydrocarbons and/or impurities contained in the airhydrocarbon vapor mixture with air and/or the solid adsorbent. Apparatus for carrying out the process of the present invention is also provided.

Dinsmore, H.L.; Schwartz, R.E.; Tuttle, W.N.

1982-08-10

322

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

Directory of Open Access Journals (Sweden)

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

Hélène Thiollet

2010-01-01

323

Biodegradation of petroleum hydrocarbons in hypersaline environments  

Scientific Electronic Library Online (English)

Full Text Available Abstract in english 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 (more) 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.

Martins, Luiz Fernando; Peixoto, Raquel Silva

2012-09-01

324

Biodegradation of petroleum hydrocarbons in hypersaline environments  

Directory of Open Access Journals (Sweden)

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.

Luiz Fernando Martins; Raquel Silva Peixoto

2012-01-01

325

Carbon isotopic composition of individual light hydrocarbons evolved from pyrolysis of source rocks from Ying-Qiong Basins, China  

Energy Technology Data Exchange (ETDEWEB)

Light hydrocarbons are an important part of natural gas, and are commonly used in gas/source rock correlation. This study determines carbon isotopic compositions of individual light hydrocarbons generated from three potential source rocks pyrolyzed at different temperatures by using GC-IRMS technique with combined glass tube pyrolysis. The results indicate that, for the natural gases from the Ying-Qiong basins, it is difficult to further identify the origin of gas in terms of carbon isotope data alone. Light hydrocarbons from pyrolysates can be divided into two main generation stages: at the lower temperature stage, light hydrocarbons are formed directly from primary cracking of kerogen, and their carbon isotopic distributions accord with isotope kinetic fractionation; at the higher temperature stage, isotopic distributions of light hydrocarbons become more complex due to the mixing of light hydrocarbons with different generation mechanisms, e.g. secondary cracking of heavy hydrocarbons. In addition, experimental results also prove that an accumulative effect may be one of major factors that cause the part reversal in carbon isotope ratios among light hydrocarbon components from the Ying-Qiong basins. (author)

Yongqiang Xiong; Ansong Geng [Chinese Acadaemy of Science, Wushan, Guangzhou (China). Guangzhou Inst. of Geochemistry

2000-11-01

326

Simple rules guide dragonfly migration  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Every year billions of butterflies, dragonflies, moths and other insects migrate across continents, and considerable progress has been made in understanding population-level migratory phenomena. However, little is known about destinations and strategies of individual insects. We attached miniaturize...

Wikelski, Martin; Moskowitz, David; Adelman, James S; Cochran, Jim; Wilcove, David S; May, Michael L

327

Structural development of salt and associated potential hydrocarbon traps, deep-water northern Gulf of Mexico  

Energy Technology Data Exchange (ETDEWEB)

The continental slope of the northern Gulf of Mexico is the frontier area where recent discoveries indicate the potential for large hydrocarbon accumulations. Multichannel seismic data of the lower continental slope of Louisiana reveal that the lower slope is underlain by shallow, continuous salt. Salt in the upper lower slope originated from the deep Jurassic salt during the initial stage of salt deformation. As the salt moved to shallower depths, the downslope part of the salt moved basinward as an allochthonous nappe, evolving into massifs and ridges in the middle lower slope. Intraslope basins formed locally by withdrawal of the allochthonous salt. Lobes of salt spread further seaward forming the Sigsbee Escarpment along the base of the slope. Various types of potential traps for hydrocarbons were created, both below and above the salt layer as a result of the intrusion of salt and subsequent withdrawal of salt. Since salt is impermeable and covers large areas, it may seal the underlying source beds. Hence, truncation of the subsalt sediment layers against the basal thrust plane of salt has the potential to trap hydrocarbons. Within the salt-withdrawal basins, hydrocarbons can escape from deep source beds along tensional faults caused by salt withdrawal or through salt-free zones caused by an evacuation of salt. Hydrocarbons can migrate into fault traps, updip pinchouts and anticlines formed by the subsidence and uplift of sediment layers associated with the withdrawal of salt.

Gwang, H.L.; Bryant, W.R.; Watkins, J.S. (Texas A and M Univ., College Station (USA))

1990-05-01

328

METHOD FOR PRODUCING AROMATIC HYDROCARBONS, AND AROMATIC HYDROCARBON PRODUCTION PLANT  

UK PubMed Central (United Kingdom)

Provided is a method for producing aromatic hydrocarbons, comprising: a step (a) in which oil feedstock such as LCO is brought into contact with a catalyst for aromatic production to obtain a reaction product containing aromatic hydrocarbons a step (b) in which the reaction product is separated into column top fraction and column bottom fraction by means of a distillation column a step (c) in which the column top fraction is separated into a crude aromatic fraction containing an LPG fraction and off gas containing hydrogen a step (d) of separating the crude aromatic fraction containing an LPG fraction into the LPG fraction and a crude aromatic fraction a step (e) of separating off gas containing hydrogen into hydrogen and off-gas and a step (f) in which the hydrogen obtained in step (e) is used to hydrocrack the crude aromatic fraction to obtain an aromatic fraction.

MINAMI HIDEKI; SUGI YOSHISHIGE; FUKUI ATSUSHI; NAGUMO ATSURO; YASUI SUSUMU; YANAGAWA SHINICHIRO

329

Consideration of hydrocarbon occurrence in Gorleben  

International Nuclear Information System (INIS)

The preliminary safety analysis of the envisaged final repository Gorleben does not yet include a systematic approach to the question whether hydrocarbons could have relevant effects on the long-term safety of the final disposal of heat-developing radioactive waste. Site specific results on the hydrocarbon occurrence were not available at the time of the preliminary safety analysis work. The report summarizes the actually available results on the hydrocarbons at the site of Gorleben and their eventual influence on the long-term safety of the repository. The following issues are covered: state of knowledge on the occurrence of hydrocarbons in saliniferous formations, hydrocarbon occurrence in the salt deposit Gorleben, hydromechanical and geochemical effects of hydrocarbon on the development of the repository system, safety-related investigations and analyses, consideration of hydrocarbons within the preliminary safety analysis Gorleben, derivation of criteria for safety considerations, conclusions and recommendations.

2012-01-01

330

Migration and Security of States  

Directory of Open Access Journals (Sweden)

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.

Cristian Jura

2012-01-01

331

Geologic setting for hydrocarbons in Tunisia  

Energy Technology Data Exchange (ETDEWEB)

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.

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

1990-05-01

332

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

Energy Technology Data Exchange (ETDEWEB)

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

Kolesnikov, Anton

2010-12-15

333

Vertical integration of three-phase-flow equations for analysis of light-hydrocarbon plume movement  

Energy Technology Data Exchange (ETDEWEB)

Groundwater contamination due to surface spills or subsurface leakage of hydrocarbon fuels, organic solvents, and other immiscible organic liquids is a widespread problem. Numerical models for phase-separated hydrocarbon migration in the vadose zone and groundwater have been presented recently by various researchers. Most analyses have been restricted to consideration of two-dimensional domains involving a vertical slice through unsaturated and/or saturated zones. In the report a mathematical model is derived for areal flow of water and light hydrocarbon in the presence of gas at atmospheric pressure. Vertical integration of the governing three-dimensional, three-phase flow equations is performed under the assumption of local vertical equilibrium to reduce the dimensionality of the problem to two orthogonal horizontal directions. Independent variables in the coupled water and hydrocarbon areal flow equations are specified as the elevation of zero gauge hydrocarbon pressure (air-oil table) and the elevation of zero gauge water pressure (air-water table). Constitutive relations required in the areal flow model are vertically integrated fluid saturations and vertically integrated fluid conductivities as functions of air-oil and air-water table elevations. Closed-form expressions for the vertically integrated constitutive relations are derived based on a three-phase extension of the Brooks-Corey saturation-capillary pressure function. Reduction in dimensionality combined with dimished nonlinearity, makes the vertically integrated water and hydrocarbon model an efficient formulation for analyzing field-scale problems involving hydrocarbon spreading or recovery under conditions for which the vertical equilibrium assumption is expected to be a satisfactory approximation.

Parker, J.C.; Lenhard, R.J.

1989-01-01

334

Distance and Intrastate College Student Migration  

Science.gov (United States)

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…

Alm, James; Winters, John V.

2009-01-01

335

Labour Migration and Network Effects in Moldova  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 differen...

Andersson, Lisa

336

INTEGRATED PROCESS FOR CONVERTING HYDROCARBON GAS TO LIQUIDS  

UK PubMed Central (United Kingdom)

Integrated process for converting light hydrocarbon gas to heavier hydrocarbon liquids. In a first embodiment, a Fisher-Tropsch (FT) process is integrated with a cryogenic liquefied natural gas (LNG) process wherein tail gas from (FT) reaction is used to drive a refrigeration compressor in the (LNG) process. The process may be further integrated with a fertilizer production process comprising an ammonia synthesis process and a urea synthesis process. To produce ammonia, hydrogen separated from synthesis gas produced in a primary and/or secondary reformer in the (FT) process is combined with nitrogen produced in the (LNG) process. Nitrogen may also be supplied to the ammonia synthesis process from an optional air separation process, which also provides oxygen enrichment to the thermal reformer in the (FT) process.; The produce urea, the ammonia is subsquently reacted with carbon dioxide removed during processing of the gas prior to its liquefaction. In an alternative embodiment, an (FT) process is integrated with a methanol synthesis process wherein tail gas from the (FT) reaction is used to fuel burners in a secondary thermal reformer.

GIESKES THOMAS

337

Mechanisms and modelling of gas migration from deep radioactive waste repositories  

International Nuclear Information System (INIS)

[en] 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)

1992-01-01

338

Scottish hydrocarbons: Borders and bounty  

International Nuclear Information System (INIS)

[en] On 6 May, the people of Scotland will vote for the country's first parliament in almost three centuries. One issue is expected to arouse particularly strong views: the question of North Sea oil and gas, and who benefits from its production and taxation. Most of these hydrocarbons lie in the northern half of the British Isles, but drawing boundaries to settle contentious issues such as oil and gas fields is not an easy task. And, if boundaries were to be drawn, then a scarcely less contentious subject arises: just how much cash might an independent Scotland expect to receive? Reading between the lines it's clear that in hard cash terms, were Scotland to be independent whilst still retaining the vast bulk of North Sea oilfields, depressed prices would ensure that hydrocarbon tax revenues would be unlikely to constitute a particularly impressive addition to the Scottish Treasury. (UK)

1999-01-01

339

Microbial production of gaseous hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

Microbial production of ethylene, isobutane and a saturated gaseous hydrocarbon mixture was described. Microbial ethylene production was studied with Penicillium digitatum IFO 9372 and a novel pathway of the ethylene biosynthesis through alpha-ketoglutarate was proposed. Rhodotorula minuta IFO 1102 was selected for the microbial production of isobutane and the interesting actions of L-leucine and L-phenylalanine for the isobutane production were found. It was finally presented about the microbial production of a saturated gaseous hydrocarbon mixture with Rhizopus japonicus IFO 4758 was described. A gas mixture was produced through a chemical reaction of SH compounds and some cellular component such as squalene under aerobic conditions. (4 figs, 7 tabs, 41 refs)

Fukuda, Hideo

1987-10-20

340

Scottish hydrocarbons: Borders and bounty  

Energy Technology Data Exchange (ETDEWEB)

On 6 May, the people of Scotland will vote for the country`s first parliament in almost three centuries. One issue is expected to arouse particularly strong views: the question of North Sea oil and gas, and who benefits from its production and taxation. Most of these hydrocarbons lie in the northern half of the British Isles, but drawing boundaries to settle contentious issues such as oil and gas fields is not an easy task. And, if boundaries were to be drawn, then a scarcely less contentious subject arises: just how much cash might an independent Scotland expect to receive? Reading between the lines it`s clear that in hard cash terms, were Scotland to be independent whilst still retaining the vast bulk of North Sea oilfields, depressed prices would ensure that hydrocarbon tax revenues would be unlikely to constitute a particularly impressive addition to the Scottish Treasury. (UK)

Roberts, John

1999-01-01

 
 
 
 
341

Enhanced liquid hydrocarbon recovery process  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a process for the recovery of liquid hydrocarbons from a subterranean hydrocarbon-bearing formation. It comprises injecting natural gas into the formation via a well in fluid communication with the formation, the natural gas being at a temperature which is insufficient to significantly mobilize light density oil in the formation and at a pressure such that the natural gas is immiscible with the light density oil in the formation, the natural gas being injected in a volume sufficient to contact light density oil in the formation within a radius from the well of about 50 meters; shutting in the well for a period of time of about 1 to about 100 days which is sufficient to render the contacted light density oil mobile; and producing the light density oil which has been mobilized by solution of the natural gas from the well.

Haines, H.K.; Monger, T.G.; Kenyon, D.E.; Galvin, L.J.

1991-06-25

342

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

Science.gov (United States)

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

Zurfluh, Michael; Biedermann, Maurus; Grob, Koni

2013-05-28

343

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

UK PubMed Central (United Kingdom)

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.

Zurfluh M; Biedermann M; Grob K

2013-01-01

344

Catalytic method for synthesizing hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

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.

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

1984-01-01

345

Hydrocarbon source potential determined by Rock Eval/TOC data from the Canadian Arctic Islands  

Energy Technology Data Exchange (ETDEWEB)

Rock Eval analysis has been used to define new hydrocarbon plays in areas of complex salt deformation on Axel Heiberg Island in the Arctic. A study was conducted in which 6320 Rock Eval and 19,700 total organic carbon (TOC) analyses from 109 oil and gas wells and 1650 outcrops were used to characterize the hydrocarbon source potential of the 18 major tectonostratigraphic successions from the Phanerozoic sedimentary basins of the Arctic Islands. The objective was to determine the quantity, quality, and thermal maturity of indigenous sedimentary organic matter and migrated hydrocarbons. This paper listed the stratigraphic successions that contain many samples with TOC greater than 1.0 per cent. Oil-prone, Type 1 and 2 kerogen is the dominant organic matter in the Silurian basinal succession, Carboniferous Emma Fiord Formation, Triassic Schei Point Group, and Cretaceous Kanguk Formation. It occurs in thin, discontinuous intervals within algal-rich beds in the Cambro-Ordovician carbonate succession; flysch shed from the Devonian Boothia uplift; shallow-water carbonates of the Devonian carbonate succession; coal in the Devonian clastic wedge; and as rare, possibly coaly intervals in the Triassic Bjorne, Barrow and Grovesnor Island formations. The thickness and extent of these oil-prone source beds are poorly constrained. These source beds are likely minor contributors to the total petroleum resource in the Arctic Islands. The S1 parameter from Rock Eval indicates the amount of migrated hydrocarbon, or those pyrolyzed at low temperatures. Histograms of S1 for each of the main hydrocarbon source rock intervals help determine if an active petroleum system was present. Histograms of the total gas derived from cuttings also reveal which source intervals may have generated gas. The Schei Point Group has very high S1 values but very low cuttings gas. The younger and less thermally mature McConnell Island-Deer Bay succession has much higher cuttings gas.

Dewing, K.; Obermajer, M.; Harrison, C. [Natural Resources Canada, Calgary, AB (Canada). Geological Survey of Canada

2007-07-01

346

Late Tertiary fluid migration in the Timor Sea: a key control on thermal and diagenetic histories?  

Energy Technology Data Exchange (ETDEWEB)

Trap integrity is probably the most important issue confronting explorers in Australia`s Timor Sea. An integrated study of the fluid flow, hydrocarbon charge and thermal histories of a suite of traps from the Timor Sea has revealed the presence of a key fluid flow event in the latest Miocene/Early Pliocene. A tripartite trap classification has been proposed, and a suite of analyses is presented from a number of wells in the area. The results of fission track and vitrinite reflectance data for the various trap types and the wider implications of the findings are discussed. Observations from the study are that fluid inclusion data have shown that hydrocarbon traps in the Timor Sea fall into three categories which relate to the relative balance between their hydrocarbon charge history. Dilatational reactivation of Mesozoic extensional faults in the Mio-Pliocene allowed hot, saline, basinal brines to migrate up major faults. Lack of appreciation of the true nature of the localized fluid flow effects could lead to erroneous thermal models being developed. Where the moderate integrity traps and low integrity traps were charged, hydrocarbons were entrained into the brines, thereby allowing hydrocarbon-related diagenetic zones to form in the Eocene sand. On a broader scale, similar late stage, local fluid flow events may be an important component of the oft-discussed `Late Tertiary heating event`, along the Western Australian margin, particularly in the Carnarvon Basin, but also potentially in the Malita Graben. (author). 3 tabs., 23 figs, refs.

O`Brien, G.W.; Fellows, M. [Australian Geological Survey Organisation, Canberra, ACT (Australia); Lisk, M. [Commonwealth Scientific and Industrial Research Organization (CSIRO), Glen Waverley, VIC (Australia). Div. of Petroleum Resources; Duddy, I.; Eadington, P.J. [Geotrack International (Australia); Cadman, S. [Bureau of Resource Sciences, Canberra, ACT (Australia)

1996-12-31

347

The financial losses from the migration of nurses from Malawi  

Directory of Open Access Journals (Sweden)

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.

Muula Adamson S; Panulo Ben; Maseko Fresier C

2006-01-01

348

The financial losses from the migration of nurses from Malawi.  

UK PubMed Central (United Kingdom)

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.

Muula AS; Panulo B Jr; Maseko FC

2006-01-01

349

Hydrocarbon potential of Altiplano and northern Subandean, Bolivia  

Energy Technology Data Exchange (ETDEWEB)

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.

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

1989-03-01

350

Dielectrophoretic deposition of dispersed phases from hydrocarbon media  

Energy Technology Data Exchange (ETDEWEB)

An explanation of the role of polarization phenomena in removal of impurities (suspended particles) from hydrocarbon media in an electrical field is presented and discussed. Dielectric parameters and relative electroconductivity of diluted suspensions of natural clayey minerals in non-polar and slightly-polar media were measured in a condenser with coaxial cylinders as a function of the level and degree of hydration of the dispersed phase. The mechanism of removal of the impurities involved addition of water to the hydroxyl-containing phase (sorbent) due to hydrogen bonds and formation of a chain of molecules, along which migration of a proton in the electrical field is possible while exchange of discharges between the particles and the hydrocarbon medium is impeded. Increase of the degree of hydration up to values corresponding to the presence of bound water (12-15%) increases particle polarizability significantly. Change of the degree of hydration of the dispersed phase during electropurification of petroleum products can intensify electrocoagulation of impurities due to the effect of hydration polarization and increase the efficiency of the process. 5 references, 3 figures.

Denega, Yu.F.; Lobastova, A.V.; Demchenko, L.N.; Ratushnyak, V.V.

1986-11-01

351

ESCAP migration study gathers momentum.  

Science.gov (United States)

A comparative study is being conducted in the ESCAP (Economic and Social Commission for Asia and the Pacific) region on the relationships of migration and urbanization to development. The 1st stage of the study will entail the preparation of country reports on the census analysis of migration, urbanization and development. The 2nd stage will involve preparation of a series of national migration surveys. The 3rd phase will involve assisting member governments to formulate a comprehensive population redistribution policy as part of their national development planning. 1st-phase country reports have been completed in Sri Lanka, South Korea, the Philippines, and Indonesia. Migration in Sri Lanka has largely been rural-to-rural with little urbanization so far. The picture in South Korea has been the opposite, with rapid urbanization in the 1960s and 1970s; the government is hoping to divert some population to smaller cities away from Seoul. The pattern in the Philippines is 1 of urban primacy with the metropolis of Manila accounting for over 1/3 of the country's total population. Indonesia is characterized by a dense heartland in the Java-Bali regions. However, the rate of urbanization here has been slower. Migrants in all the countries studied are preponderantly young. The sex differential varies from country to country. The influence of migration on subsequent fertility is unknown. PMID:12262021

1980-01-01

352

International nurse migrations: Global trends  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents global trends of migration of nurses, as specific qualified personnel in high demand. In the last couple of decades, and especially in the last couple of years, many countries have faced the problem of insufficient healthcare workers, particularly nurses. Reasons for this occurrence might be found in the deficiencies of their education systems, as well as the population aging of northern and western countries. As a response to this deficiency, those countries have begun intensive recruitment of foreign qualified female healthcare workers, which has led to the point that nurse migration today presents a very intense, and by many accounts specific migration flow. Female migrating work force is often in pursuit of low-wage and lowqualified work. Nurse migration is actually an example of motion of qualified female migrants in pursuit for better employment opportunities. While such a way of filling up the vacant positions works for the “importing” countries as a temporary solution, departure of trained female personnel presents a significant loss for the originating countries. In this paper we pay special attention to the countries who are the main “importers”, but also to those who are “exporters” of nursing personnel, and to specific national strategies these countries have applied.

Ivkovi? Marija

2011-01-01

353

Process and apparatus for recovering hydrocarbons from air-hydrocarbon vapor mixtures  

Energy Technology Data Exchange (ETDEWEB)

An improved process and apparatus are claimed for recovering hydrocarbons from an air-hydrocarbon vapor mixture such as the mixture of air and vaporized light hydrocarbon compounds expelled as a result of loading gasoline or the like into storage tanks and tank trucks. The air-hydrocarbon vapor mixture is caused to flow through a bed of solid adsorbent so that the hydrocarbons are removed from the mixture and a residue gas stream comprised of substantially hydrocarbon-free air is produced. The substantially hydrocarbon free air is vented to the atmosphere and a second bed of solid adsorbent having hydrocarbons adsorbed thereon is subjected to conditions which cause desorption of the hydrocarbons and thereby regeneration of the bed. The flow pattern of the inlet air-hydrocarbon vapor mixture and the bed of solid adsorbent being regenerated are periodically changed so that when the bed through which the inlet air-hydrocarbon mixture is flowing becomes loaded with adsorbed hydrocarbons, the inlet air-hydrocarbon mixture is caused to flow through the bed which has just been regenerated. The regeneration of the beds is accomplished by evacuating the beds with vacuum pumping so that a major portion of the hydrocarbons are desorbed therefrom and subsequently introducing a small quantity of heated hydrocarbon-free air into the beds so that additional hydrocarbons are stripped therefrom. The airhydrocarbon vapor mixture produced in the regeneration of the beds is contacted with a heated first portion and a second portion of a liquid absorbent so that a major portion of the hydrocarbons are absorbed therefrom and recovered. The first portion is heated by passing it in heat exchange relationship with a seal liquid used in a vacuum pump which effects the vacuum pumping of the adsorbent beds. Apparatus for carrying out the process of the invention is also described.

Dinsmore, H.L.

1981-06-30

354

Redox reactions in hydrocarbon clastic reservoirs: Experimental validation of this mechanism for porosity enhancement  

Energy Technology Data Exchange (ETDEWEB)

Experiments evaluated oil-rock-water reactions in hydrocarbon reservoirs. Ten to 20 cm{sup 3} of hematitic Tensleep Sandstone were heated with 200 cc of deionized water and 100 cc of petroleum for 3 to 14 days at 200{degrees} to 365{degrees}C. Results indicate significant potential exists for redox reactions between oxidized mineral phases and crude oil. Iron oxides ({plus_minus} sulphate) were reduced and hydrocarbons were oxidized to oxygenated organic compounds. Organic acids generated during the redox reactions partitioned into the system water, attacking unstable minerals and cements (primarily carbonates). Simultaneously, oil and water may have reacted to produce saturated, lighter hydrocarbons. Geochemical modeling indicates the system was consistently undersaturated with respect to both calcite and dolomite, thereby favoring carbonate dissolution and secondary porosity generation. Original porosity of the samples ranged from 6 to 15%, and increased by 12-20% after experimentation. Redox reactions do occur and result in significantly enhanced sandstone reservoir porosity.

Shebl, M.A.; Surdam, R.C. [Institute for Energy Research, Laramie, WY (United States)

1995-12-01

355

METHOD OF TREATING A HYDROCARBON STREAM COMPRISING CYCLOPENTADIENE AND ONE OR MORE DIOLEFINS  

UK PubMed Central (United Kingdom)

A method of treating a hydrocarbon stream comprising cyclopentadiene (CPD) and one or more diolefins, the method comprising: providing a hydrocarbon stream comprising an initial CPD concentration, an initial target diolefin concentration, and an initial secondary diolefin concentration subjecting the hydrocarbon stream to preseparation conditions effective to separate (a) a crude target diolefin feedstock having a decreased concentration of CPD and an increased target diolefin concentration, and (b) a CPD dimerization feedstock having a decreased target diolefin concentration and an increased CPD concentration that is 1.5 or more times the initial CPD concentration subjecting the CPD dimerization feedstock to CPD dimerization conditions effective to produce a raw DCPD stream comprising 20 wt. % or more DCPD and, separating a high purity DCPD product stream comprising 90 wt. % or more DCPD from the raw DCPD stream.

ANZICK ROBERT KENNETH; BLACKBOURN ROBERT LAWRENCE; NAYARAJAN SIVAKUMAR

356

Endoscopic management of migrated biliary stent causing sigmoid perforation.  

UK PubMed Central (United Kingdom)

Endoscopically deployed biliary stents are a well established method for dealing with biliary diseases. Perforation of the gut secondary to migrated biliary stent is reported in less than 1% cases. The authors present the first case of a colonic perforation from migrated biliary stent which was managed endoscopically. An 82-year-old female had a biliary stent for a postcholecystectomy bile leak and presented 6 months later with left iliac fossa pain. Barium enema showed a stent perforating the sigmoid colon. In view of the patient's frailty and absence of peritonitis, an endoscopic retrieval of stent was attempted. Flexible sigmoidoscopy showed a stent partially embedded within the sigmoid diverticulum which was successfully removed and the defect was closed endoscopically using three titanium clips. She had an uncomplicated recovery following the procedure and was discharged home on the second day following the procedure.

Jafferbhoy SF; Scriven P; Bannister J; Shiwani MH; Hurlstone P

2011-01-01

357

The brown dwarf desert as a consequence of orbital migration  

CERN Multimedia

We show that the dearth of brown dwarfs in short-period orbits around Solar-mass stars - the brown dwarf desert - can be understood as a consequence of inward migration within an evolving protoplanetary disc. Brown dwarf secondaries forming at the same time as the primary star have masses which are comparable to the initial mass of the protoplanetary disc. Subsequent disc evolution leads to inward migration, and destruction of the brown dwarf, via merger with the star. This is in contrast with massive planets, which avoid this fate by forming at a later epoch when the disc is close to being dispersed. Within this model, a brown dwarf desert arises because the mass at the hydrogen burning limit is coincidentally comparable to the initial disc mass for a Solar mass star. Brown dwarfs should be found in close binaries around very low mass stars, around other brown dwarfs, and around Solar-type stars during the earliest phases of star formation.

Armitage, P J; Armitage, Philip J.; Bonnell, Ian A.

2002-01-01

358

The International-Migration Network  

CERN Multimedia

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.

Fagiolo, Giorgio

2012-01-01

359

Families, children, migration and AIDS.  

UK PubMed Central (United Kingdom)

Migration is very often a family affair, and often involves children, directly or indirectly. It may give rise to better quality of life for an entire family, or to bitter disappointment, and may also increase vulnerability to HIV and AIDS. This review, carried out for the Joint Learning Initiative on Children and AIDS, links the literature on "migration", on "HIV and AIDS" and on "families". Three themes are sketched: (1) As both HIV prevalence and circular migration increase, former migrant workers affected by AIDS may return to their families for care and support, especially at the end of life, often under crisis conditions. Families thus lose promising members, as well as sources of support. However, very little is known about the children of such migrants. (2) Following patterns of migration established for far different reasons, children may have to relocate to different places, sometimes over long distances, if their AIDS-affected parents can no longer care for them. They face the same adaptation challenges as other children who move, but complicated by loss of parent(s), AIDS stigma, and often poverty. (3) The issue of migrant families living with HIV has been studied to some extent, but mainly in developed countries with a long history of migration, and with little attention paid to the children in such families. Difficulties include involuntary separation from family members, isolation and lack of support, disclosure and planning for children's care should the parent(s) die and differences in treatment access within the same family. Numerous research and policy gaps are defined regarding the three themes, and a call is made for thinking about migration, families and AIDS to go beyond description to include resilience theory, and to go beyond prevention to include care.

Haour-Knipe M

2009-01-01

360

Shallow temperatures and thermal regime in the hydrocarbon province of Tierra del Fuego  

Energy Technology Data Exchange (ETDEWEB)

A suite of shallow (<2 m deep) thermal measurements across the San Sebastian oil and gas field, northeastern Tierra del Fuego, indicates at least a 200 mWm/sup -2/ (5 HFU) thermal anomaly over the field. The anomaly appears to be of subsurface origin and, due to its magnitude, must be caused by a localized discharge of deep groundwater. A single published heat flow value and deep bottom hole temperature data for the area suggest a regional heat flow that is at least 20 mWm/sup -2/ (0.5 HFU) higher than the world average for similar tectonic provinces (post-Precambrian non-orogenic). Maturation level estimates based on the heat flow and burial history of sediments suggest considerable lateral migration (at least 100 km) of hydrocarbons from deeper in the Magellan basin. From estimates of the timing of possible oil generation, minimum average migration velocity is within 1 or 2 orders of magnitude of the groundwater velocity required to cause the local and regional heat flow anomalies. This suggests that groundwater moving from deeper in the Magellan basin might simultaneously transport hydrocarbons and heat to the area. Volume flux estimates require hydrocarbon concentrations significantly greater than possible via aqueous molecular solution.

Zielinski, G.W. (Gulf Science and Tech. Co., Pittsburgh, PA); Bruchhausen, P.M.

1983-01-01

 
 
 
 
361

Shallow temperatures and thermal regime in the hydrocarbon province of Tierra del Fuego  

Energy Technology Data Exchange (ETDEWEB)

A suite of shallow (<2 m deep) thermal measurements across the San Sebastian oil and gas field, northeastern Tierra del Fuego, indicates at least a 200 mWm/sup -2/ (5 HFU) thermal anomaly over the field. The anomaly appears to be of subsurface origin and, due to its magnitude, must be caused by a localized discharge of deep ground water. A single published heat flow value and deep bottom hole temperature data for the area suggest a regional heat flow that is at least 20 mWm/sup -2/ (0.5 HFU) higher than the world average for similar tectonic provinces (postPrecambrian non-orogenic). Maturation level estimates based on the heat flow and burial history of sediments suggest considerable lateral migration (at least 100 km) of hydrocarbons from deeper in the Magellan basin. From estimates of the timing of possible oil generation, minimum average migration velocity is within 1 or 2 orders of magnitude of the ground water velocity required to cause the local and regional heat flow anomalies. This suggests that ground water moving from deeper in the Magellan basin might simultaneously transport hydrocarbons and heat to the area. Volume flux estimates require that hydrocarbon concentrations significantly greater than possible via aqueous molecular solution.

Zielinski, G.W.; Bruchhausen, P.M.

1983-01-01

362

The hydrocarbon habitat of northern South America: Colombia-Venezuela-Trinidad  

Energy Technology Data Exchange (ETDEWEB)

A prolific hydrocarbon province extends across the northern margin of South America from Colombia to east of Trinidad. Two key components are a world-class source rock, formed on a regional Late Cretaceous passive margin, and a complex tectonic setting in which a variety of structural and stratigraphic traps, reservoirs, seals and hydrocarbon kitchens have evolved through time. Convergence between the Farallon and Caribbean plates with South America culminated in the late Cretaceous-early Palaeogene with emplacement of Colombia`s Central Cordillera in the west and a nappe-foreland basin system in the north. Regional hydrocarbon generation probably occurred below associated basins. Subsequent oblique convergence between the Caribbean and South America, partitioned into strike-slip and compressional strain, generated an eastward migrating and ongoing uplift-foredeep (kitchen) system from central Venezuela to Trinidad. Similarly, oblique interaction of western Colombia with the Nazca Plate caused segmentation of the earlier orogen, northward extrusion of elements such as the Maracaibo Block, and eastward migration of uplift progressively dividing earlier kitchens into localized foredeeps.

James, K.H. [Conoco, Inc., Houston, TX (United States)

1996-08-01

363

Petroleum hydrocarbon pollution of Lake Burley Griffin  

Energy Technology Data Exchange (ETDEWEB)

Aromatic hydrocarbons were measured in Lake Burley Griffin by fluorescence spectroscopy to gain an estimate of the pollution of the lake by petroleum hydrocarbons. Aromatic hydrocarbons are reported as equivalents of m-terphenyl(T) and chrysene(C). observed concentrations are 0.3-2.2{mu}g/litre (T) and 0.1 -0.5{mu}g/litre (C). Widespread distribution of fuel distillates is evident with only a small contribution from lubricating and heavier oils. (author).

Maher, W.; Tomlins, C.; Furlonger, J. (Canberra Coll. of Advanced Education, Belconnen (AU). Water Research Center)

1990-01-01

364

HYDROCARBON AND SULFUR SENSORS FOR SOFC SYSTEMS  

Energy Technology Data Exchange (ETDEWEB)

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.

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

2003-11-01

365

Multiple receptor systems promote CNS neural migration.  

UK PubMed Central (United Kingdom)

To identify glial receptor systems in CNS migration, cerebellar granule neuron migration was assayed on glass fibers coated with polylysine, astroglial membranes (AM fibers), or the extracellular matrix proteins collagen (COLL fibers), fibronectin (FN fibers), and laminin (LAM fibers). By video microscopy, granule cells migrated along AM fibers with the cytology, neuron-fiber apposition, and dynamics seen on living glia. The demonstration that immobilized astroglial membranes support neural migration suggests that astroglial receptor systems, in combination with glial fiber geometry, promote CNS neural migration. Moreover, granule neurons migrated rapidly on LAM fibers, moved relatively slowly on FN fibers, and not at all on COLL fibers. Antibody perturbation analyses suggested that, whereas astrotactin provides the neural receptor for migration on astroglial membranes, integrin beta 1 provides the neural receptor for migration on LAM fibers. These results suggest that multiple receptor systems support CNS neural migration.

Fishman RB; Hatten ME

1993-08-01

366

Understanding SOA Migration Using a Conceptual Framework  

Directory of Open Access Journals (Sweden)

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.

Maryam Razavian; Patricia Lago

2010-01-01

367

Hydrothermal dolomitization in the Lower Silurian La Vieille Formation in northern New Brunswick : geological context and significance for hydrocarbon exploration  

Energy Technology Data Exchange (ETDEWEB)

Since hydrothermal dolomites are known to host hydrocarbon reservoirs, they constitute a significant play for exploration companies seeking large hydrocarbon reservoirs. The process of hydrothermal alteration and dolomitization has been documented in the Gaspe Peninsula and in northern New Brunswick. This study described the hydrocarbon potential of the Late Ordovician to Middle Devonian Gaspe Belt in northern New Brunswick with particular reference to evidence of hydrothermal alteration of the limestone facies. Six stratigraphic sections of the Lower Silurian La Vieille Formation were examined during the summer of 2004 for facies architecture. The observations that substantiate hydrothermal alteration of the La Vieille Formation include early fractures; brecciation associated with early fractures; dissolution features associated with early fractures; large scale collapse of sections; fracture-filling cements; pervasive dolomitization; and, synsedimentary tectonic instability. Early hydrothermal alternation also resulted in leaching and the development of porous intervals into which hydrocarbons migrated. Forty-five samples were collected for petrographic and carbon and oxygen stable isotope ratios analysis. It was concluded that thermal maturation in areas of northern New Brunswick is conducive for preservation of hydrocarbons and that Upper Ordovician hydrocarbon source rocks may be present. 56 refs., 2 tabs., 10 figs.

Lavoie, D. [Natural Resources Canada, Quebec, PQ (Canada). Geological Survey of Canada, Quebec Division; Chi, G. [Regina Univ., SK (Canada). Dept. of Geology

2006-12-15

368

Is international economic migration spreading?  

UK PubMed Central (United Kingdom)

"Are the numbers of migrants growing? Proof is hard to come by--many countries' statistics do not provide reliable data for legal migration; most countries do not have good estimates for illegal migration; quite a few have no useable data at all, especially migrant-sending countries. We make use of an alternative yardstick, which over a period of time compares the number of countries that receive foreigners who are economically active or that are these persons' countries of origin.... Our yardstick includes only countries of a minimum population size fixed in terms of a comparable population base in the years 1970 and 1990."

Bohning WR; Oishi N

1995-01-01

369

Radionuclide migration through fractured granite  

International Nuclear Information System (INIS)

Radionuclide migration has been studied in natural fractures in granite blocks of up to 30 cm in length. Results are reported for four migration experiments involving synthetic groundwaters containing tritiated water, 95mTc, 75Se, 137Cs, or 60Co-labelled natural colloids, which were injected into the fractures at flow rates of 0.4-0.45 mL/h, giving residence times in the fractures of up to 15 h. Also presented are the results of the post-experiment analyses, including an autoradiograph of one of the fracture surfaces, and the spatial distribution of the sorbed radionuclides determined by ?-scanning and selective chemical extractions

1988-01-01

370

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

1993-04-03

371

International Migration, Remittances and Development  

Directory of Open Access Journals (Sweden)

Full Text Available The increasing remittance flows to the labor sending developing countries in recent years have generated huge optimism in the contemporary development discourse about the possibility of development at the grassroots levels which has been an overwhelming challenge for the development actors for decades. However, the realization of such potential proves difficult due to a lack of common understanding of the phenomenon of labor migration and its causes and consequences. This study focuses on the existing literature on international labor migration, its causes and consequences with a view to identify a common line of theorizing about the issue in question. 

Hasan Mahmud; Md. Abdus Sabur; Sharmin Tamanna

2009-01-01

372

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)

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, becau

Assouline, F.

2001-07-01

373

Recovery of hydrocarbons from acid sludge  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a process for the recovery of hydrocarbon from an acid sludge disposal site containing an aged acid sludge, the aged acid sludge containing up to 13 weight percent sulfuric acid. It comprises removing the aged acid sludge from the disposal site; contacting the aged acid sludge with methyl ethyl ketone and base to form a mixture; separating from the mixture a hydrocarbon-rich methyl ethyl ketone stream and a solids-containing stream; and separating from the hydrocarbon-rich methyl ethyl ketone stream a methyl ethyl ketone stream, a hydrocarbon stream and a waste water stream.

Luce, M.C.

1991-09-17

374

Membrane separation of hydrocarbons using cycloparaffinic solvents  

Energy Technology Data Exchange (ETDEWEB)

Heavy crude oils which contain metal contaminants such as nickel, vanadium and iron may be separated from light hydrocarbon oils by passing a solution of the crude oil dissolved in a cycloparaffinic hydrocarbon solvent containing from about 5 to about 8 carbon atoms by passing through a polymeric membrane which is capable of maintaining its integrity in the presence of hydrocarbon compounds. The light hydrocarbon oils which possess relatively low molecular weights will be recovered as the permeate while the heavy oils which possess relatively high molecular weights as well as the metal contaminants will be recovered as the retentate.

Kulkarni, Sudhir S. (Hoffman Estates, IL); Chang, Y. Alice (Westmont, IL); Gatsis, John G. (Des Plaines, IL); Funk, Edward W. (Highland Park, IL)

1988-01-01

375

Neuropathy secondary to drugs  

Science.gov (United States)

Neuropathy secondary to drugs is a loss of sensation or movement in a part of the body ... weakness. Many medications may affect the development of neuropathy, including: Heart or blood pressure medications Amiodarone Hydralazine ...

376

Poza Rica: 29 years of secondary recovery  

Energy Technology Data Exchange (ETDEWEB)

One of the main objectives of the Mexican Goverment is the suitable exploitation of its hydrocarbon reservoirs. Therefore, the application of secondary recovery methods in those reservoirs sensitive to this method was increased. Petroleos Mexicanos has 27 systems of waterflooding in operation; 30% more than in 1976. The main objective is the continuous analysis of the optimum conditions, in order to optimize the efficiency of the waterflooding process, such as in the Tamabra formation in the Poza Rica field. A history is presented of the waterflooding process utilized in the Poza Rica field to increase the oil production from the Tamabra formation. Geology and reservoir characteristics, antecedents, producing well requirements, project development, future programs, and economic analyses are presented.

Ortega, H.G.

1981-03-01

377

Labour Force Migration Effects within European Union  

Directory of Open Access Journals (Sweden)

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.

Carmen Mihaela Tudorache

2006-01-01

378

Asian migration and international relations: future perspectives  

Directory of Open Access Journals (Sweden)

Full Text Available Migration has been largely neglected in the study of international relations. However, complex changes involving the formation of transnational communities and the relativization of borders, and the challenges posed by ensuring security, furthering development, and establishing good governance require a fresh look into the issue. Thispaper only indicates some directions, considering the Asian region as the context. First, migration is considered an issue affecting international relations because of security concerns. Second, the impact of migration on international relations is approached fromthe role of migration in economic relations. Finally, the link between governance and migration as well as international aspects in the management of migration are examined.

Graziano Battistella

2005-01-01

379

Development of a secondary organic aerosol formation mechanism: comparison with smog chamber experiments and atmospheric measurements  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A new mechanism to simulate the formation of secondary organic aerosols (SOA) from reactive primary hydrocarbons is presented, together with comparisons with experimental smog chamber results and ambient measurements found in the literature. The SOA formation mechanism is based on an approach using ...

L. E. Olcese; J. E. Penner; S. Sillman

380

METHOD FOR PRODUCING AROMATIC HYDROCARBONS  

UK PubMed Central (United Kingdom)

A method for producing aromatic hydrocarbons by bringing a feedstock derived from a fraction containing a light cycle oil produced in a fluid catalytic cracking into contact with a catalyst containing a crystalline aluminosilicate, wherein the proportion of the naphthene content within the feedstock is adjusted so as to be greater than the proportion of the naphthene content in the fraction containing the light cycle oil, and the contact between the feedstock and the catalyst is performed under a pressure within a range from 0.1 MPaG to 1.0 MPaG.

YANAGAWA SHINICHIRO; AOKI YUKO; HAYASAKA KAZUAKI

 
 
 
 
381

BIODEGRADABILITY OF HYDROCARBONS BY CYANOBACTERIA  

UK PubMed Central (United Kingdom)

Five cyanobacterial species (Phormidium sp., Nostoc sp., Anabaena sp. Aphanothece conferta, and Synechocystis aquatilis) isolated from the Suez Canal coast at the city of Ismailia (Egypt) were tested for biodegradation of four hydrocarbon (HC) compounds: two aliphatic compounds (n-octadecane and pristine) and two aromatic compounds (phenanthrene and dibenzothiophene). High degradation efficiencies for the two aliphatic compounds were measured for A. conferta (64% for n-octadecane and 78% for pristine) and S. aquatilis (85% for n-octadecane and 90% for pristane). However, the other biodegradation percentages ranged between weak and moderate percentages.

Ibraheem IbraheemBorieMohammad

2010-08-01

382

Commercial valuation of hydrocarbon resources  

International Nuclear Information System (INIS)

[en] 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

1995-01-01

383

Commercial valuation of hydrocarbon resources  

Energy Technology Data Exchange (ETDEWEB)

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.

Boardman, J.S.

1995-10-01

384

Hydrocarbon release investigations in Missouri  

Energy Technology Data Exchange (ETDEWEB)

Hydrocarbon releases are among the most common environmental problems in Missouri, as well as across the country. Old, unprotected underground storage tanks and buried piping from the tanks to pumps are notorious sources of petroleum contamination at LUST (leaking underground storage tank) sites. Missouri has an estimated 5000 LUST sites across the state with the majority being simple spills into clay-rich soils or into a shallow perched water system. However, in the southern half of the state, where residual soils and karst bedrock are not conducive to trapping such releases, significant groundwater supplies are at risk. This article discusses the process used to identify the source of contamination.

Fels, J.B. [LUST Unit, Rolla, MO (United States)

1996-09-01

385

Hydrocarbon bioremediation 2(2)  

Energy Technology Data Exchange (ETDEWEB)

Hydrocarbon contamination of soil and groundwater, although less visible, is even more widespread than oil spills and is the background for a number of studies presented in this book, in addition to those devoted to shoreline spills. Chapters address a wide variety of theory and practice and cover important subjects such as biofiltration, natural attenuation, surfactants, and the use of in situ bioventing compared to soil venting. This book represents the collective experience of practitioners and researchers in North America, Europe, Africa, and Asia.

Hinchee, R.E.; Alleman, B.C.; Hoeppel, R.E.; Miller, R.N.

1993-12-31

386

Applied bioremediation of petroleum hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

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.

Hinchee, R.E.; Kittel, J.A. [eds.] [Battelle Memorial Inst., Columbus, OH (United States); Reisinger, H.J. [ed.] [Integrated Science and Technology, Inc., Marietta, GA (United States)

1995-12-31

387

Finite element analysis and ray tracing modeling of petroleum migration  

Energy Technology Data Exchange (ETDEWEB)

Separate phase flow is the dominant transport mechanism for secondary migration of petroleum phases. Commonly two different methods are used for the modeling of separate phase flow: full 3D modeling (finite element analysis) which leads to the physically best description but can only be performed on low resolution grids, and flowpath modeling (ray tracing) which can be performed on high resolution grids but is based on simplified physical assumptions. A new approach that integrates both methods allows a physically realistic description without losing any of the original geometric information. This new approach cuts processing times considerably. (author)

Hantschel, T.; Kauerauf, A.I.; Wygrala, B. [Integrated Exploration Systems (IES) GmbH, Juelich (Germany)

2000-08-01

388

[Lymphocyte migration inhibition in rabbit experimental syphilis (author's transl)  

UK PubMed Central (United Kingdom)

During rabbit experimental syphilis a suspension of Treponema pallidum (TP) was used as antigen. The evolution of anti TP antibodies was followed up to the fifteenth month, the antibody titer was maximum at month seven. A stimulation of leukocytes migration test was observed up to the sixth month then a significant inhibition appeared (chi square test) which persists after the ninth month. Hence the possibility was discussed that some form of cellular immunity appears secondary while immune response was mostly of humoral type at the beginning of the disease.

Noly JC; Sepetjan M; Monier JC

1979-03-01

389

Clocks, cryptochromes and Monarch migrations.  

UK PubMed Central (United Kingdom)

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.

Kyriacou CP

2009-01-01

390

Clocks, cryptochromes and Monarch migrations.  

Science.gov (United States)

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. PMID:19591650

Kyriacou, Charalambos P

2009-06-18

391

Planetary migration in protoplanetary disks  

CERN Document Server

In the current paper, we further develop the model for the migration of planets introduced in Del Popolo et al. (2001) and extended to time-dependent accretion discs in Del Popolo and Eksi (2002). We use a method developed by Stepinski and Valageas (1996, 1997), that is able to simultaneously follow the evolution of gas and solid particles for up to $10^7 {\\rm yr}$. The disc model is coupled to the migration model introduced in Del Popolo et al. (2001) in order to obtain the migration rate of the planet in the planetesimal disc. We find that in the case of discs having total mass of $10^{-3}-0.1 M_{\\odot}$, and $0.1<\\alpha<0.0001$, planets can migrate inward a large distance while if $M<10^{-3} M_{\\odot}$ the planets remain almost in their initial position for $0.1<\\alpha<0.01$ and only in the case $\\alpha<0.001$ the planets move to a minimum value of orbital radius of $\\simeq 2 {\\rm AU}$. The model gives a good description of the observed distribution of planets in the period range 0-20 day...

Popolo, A D

2003-01-01

392

International Migration of Power Couples  

DEFF Research Database (Denmark)

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.

Munk, Martin D.; Junge, Martin

393

[Migration of dentists within Hungary].  

UK PubMed Central (United Kingdom)

Concerning the human resource management in the health care, Hungarian analysts focus mainly on cross-national migration, which was instigated considerably by joining the European Union in 2004. Contrasted to other health care professionals, dentists emphasized also the importance of in-country migration (mobility) indicating serious dangers of developing inequalities in the dental service. From the point of view of health system planning, the main problem is to balance the needs and the number of professionals in regions and areas with extremely different socio-economic conditions. Under dictatorial governments, this "balancing" (which was experienced also in Hungary) is a forced allocation of young professionals to the target regions. In political freedom and free market economy, these measures are unthinkable. The present domestic area distribution, concerning also the supply through vacancies by old age inactivity and cross-national migration, is ruled by personal decisions of actually graduated and immigrant professionals respectively. Therefore, it is unavoidable to investigate the interrelation of factors (dentists' births place, study migration and decisions for practice allocation) ruling the in-country geographic patterns of dental practices. This evidence-based knowledge can only explain the present situation and provide guidelines for health policy decision makers.

Balázs P

2010-09-01

394

VORTEX MIGRATION IN PROTOPLANETARY DISKS  

International Nuclear Information System (INIS)

We consider the radial migration of vortices in two-dimensional isothermal gaseous disks. We find that a vortex core, orbiting at the local gas velocity, induces velocity perturbations that propagate away from the vortex as density waves. The resulting spiral wave pattern is reminiscent of an embedded planet. There are two main causes for asymmetries in these wakes: geometrical effects tend to favor the outer wave, while a radial vortensity gradient leads to an asymmetric vortex core, which favors the wave at the side that has the lowest density. In the case of asymmetric waves, which we always find except for a disk of constant pressure, there is a net exchange of angular momentum between the vortex and the surrounding disk, which leads to orbital migration of the vortex. Numerical hydrodynamical simulations show that this migration can be very rapid, on a timescale of a few thousand orbits, for vortices with a size comparable to the scale height of the disk. We discuss the possible effects of vortex migration on planet formation scenarios.

2010-12-10

395

Cryptococcus neoformans and neutrophil migration  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This thesis has focused on several aspects of cryptococcal glucuronoxylomannan (GXM)-related interference with neutrophil migration into inflammatory sites. First, the effect of GXM on neutrophil adhesion (rolling and firm adhesion) to the endothelium was investigated and potential mechanisms were e...

Ellerbroek, P.M.