Distribution of "Compound" and "Simple" Flows in the Deccan Traps (India)

Science.gov (United States)

Vanderkluysen, L.; Self, S.; Jay, A. E.; Sheth, H. C.; Clarke, A. B.

2014-12-01

The Deccan Traps are a dominantly mafic large igneous province (LIP) that, prior to erosion, covered ~1 million km2 of west-central India with lava flows. The type sections of the Western Ghats escarpment, where the Deccan lava pile reaches a maximum reconstructed stratigraphic thickness of ~3400 m, are subdivided into eleven formations defined on chemo-stratigraphic grounds. Earlier work recognized that emplacement of Deccan basalt flows primarily occurs following two main modes: as a stack of meter-sized pāhoehoe toes and lobes, termed "compound" flows; or as inflated sheet lobes tens to hundreds of meters in width and meters to tens of meters in height, previously termed "simple" flows. Initially, the distribution of small lobes and sheet lobes in the Deccan was thought to be controlled by distance from source, but later work suggested the distribution to be mainly controlled along stratigraphic, formational boundaries, with six of the lower formations being composed exclusively of compound flows, and the upper 4-5 formations being wholly built of sheet lobes. This simple stratigraphic subdivision of lava flow morphologies has also been documented in the volcanic architecture of other LIPs, e.g., the Etendeka, the Ethiopian Traps, and in the Faeroe Islands (North Atlantic LIP). Upon examination of eight sections carefully logged along the Western Ghats, this traditional view must be challenged. Where the lower Deccan formations crop out, we found that as much as 65% of the exposed thickness (below the Khandala Formation) is made up of sheet lobes, from 40% in the Bhimashankar Formation to 75% in the Thakurvadi Formation. Near the bottom of the sequence, 25% of the Neral Formation is composed of sheet lobes ≥15 m in thickness. This distribution in lava flow morphology does not seem to be noticeably affected by the inferred distance to the source (based on the location of similar-composition dikes for each formation). Several mechanisms have been proposed to

Discovery of Jurassic ammonite-bearing series in Jebel Bou Hedma (South-Central Tunisian Atlas): Implications for stratigraphic correlations and paleogeographic reconstruction

Science.gov (United States)

Bahrouni, Néjib; Houla, Yassine; Soussi, Mohamed; Boughdiri, Mabrouk; Ali, Walid Ben; Nasri, Ahmed; Bouaziz, Samir

2016-01-01

Recent geological mapping undertaken in the Southern-Central Atlas of Tunisia led to the discovery of Jurassic ammonite-bearing series in the Jebel Bou Hedma E-W anticline structure. These series represent the Southernmost Jurassic rocks ever documented in the outcrops of the Tunisian Atlas. These series which outcrop in a transitional zone between the Southern Tunisian Atlas and the Chott basin offer a valuable benchmark for new stratigraphic correlation with the well-known Jurassic series of the North-South Axis of Central Tunisia and also with the Jurassic subsurface successions transected by petroleum wells in the study area. The preliminary investigations allowed the identification, within the most complete section outcropping in the center of the structure, of numerous useful biochronological and sedimentological markers helping in the establishment of an updated Jurassic stratigraphic framework chart of South-Western Tunisia. Additionally, the Late Jurassic succession documents syn-sedimentary features such as slumping, erosion and reworking of sediments and ammonite faunas that can be considered as strong witnesses of an important geodynamic event around the Jurassic-Cretaceous boundary. These stratigraphic and geodynamic new data make of the Jurassic of Jebel Bou Hedma a key succession for stratigraphic correlation attempt between Atlas Tunisian series and those currently buried in the Chott basin or outcropping in the Saharan platform. Furthermore, the several rich-ammonite identified horizons within the Middle and Upper Jurassic series constitute reliable time lines that can be useful for both paleogeographic and geodynamic reconstructions of this part of the North African Tethyan margin but also in the refinement of the potential migration routes for ammonite populations from the Maghrebian Southern Tethys to Arabia.

The stratigraphic filter and bias in measurement of geologic rates

Science.gov (United States)

Schumer, Rina; Jerolmack, Douglas; McElroy, Brandon

2011-01-01

Erosion and deposition rates estimated from the stratigraphic record frequently exhibit a power-law dependence on measurement interval. This dependence can result from a power-law distribution of stratigraphic hiatuses. By representing the stratigraphic filter as a stochastic process called a reverse ascending ladder, we describe a likely origin of power-law hiatuses, and thus, rate scaling. While power-law hiatuses in certain environments can be a direct result of power-law periods of stasis (no deposition or erosion), they are more generally the result of randomness in surface fluctuations irrespective of mean subsidence or uplift. Autocorrelation in fluctuations can make hiatuses more or less heavy-tailed, but still exhibit power-law characteristics. In addition we show that by passing stratigraphic data backward through the filter, certain statistics of surface kinematics from their formative environments can be inferred.

Measuring Stratigraphic Congruence Across Trees, Higher Taxa, and Time.

Science.gov (United States)

O'Connor, Anne; Wills, Matthew A

2016-09-01

The congruence between the order of cladistic branching and the first appearance dates of fossil lineages can be quantified using a variety of indices. Good matching is a prerequisite for the accurate time calibration of trees, while the distribution of congruence indices across large samples of cladograms has underpinned claims about temporal and taxonomic patterns of completeness in the fossil record. The most widely used stratigraphic congruence indices are the stratigraphic consistency index (SCI), the modified Manhattan stratigraphic measure (MSM*), and the gap excess ratio (GER) (plus its derivatives; the topological GER and the modified GER). Many factors are believed to variously bias these indices, with several empirical and simulation studies addressing some subset of the putative interactions. This study combines both approaches to quantify the effects (on all five indices) of eight variables reasoned to constrain the distribution of possible values (the number of taxa, tree balance, tree resolution, range of first occurrence (FO) dates, center of gravity of FO dates, the variability of FO dates, percentage of extant taxa, and percentage of taxa with no fossil record). Our empirical data set comprised 647 published animal and plant cladograms spanning the entire Phanerozoic, and for these data we also modeled the effects of mean age of FOs (as a proxy for clade age), the taxonomic rank of the clade, and the higher taxonomic group to which it belonged. The center of gravity of FO dates had not been investigated hitherto, and this was found to correlate most strongly with some measures of stratigraphic congruence in our empirical study (top-heavy clades had better congruence). The modified GER was the index least susceptible to bias. We found significant differences across higher taxa for all indices; arthropods had lower congruence and tetrapods higher congruence. Stratigraphic congruence-however measured-also varied throughout the Phanerozoic, reflecting

Escaping the tolerance trap

International Nuclear Information System (INIS)

Hammoudeh, S.; Madan, V.

1994-01-01

In order to examine the implications of the weakening of OPEC's responsiveness in adjusting its production levels, this paper explicitly incorporates rigidity in the quantity adjustment mechanism, thereby extending previous research which assumed smooth quantity adjustments. The rigidity is manifested in a tolerance range for the discrepancy between the declared target price and that of the market. This environment gives rise to a 'tolerance trap' which impedes the convergence process and inevitably brings the market to a standstill before its reaches the targeted price and revenue objectives. OPEC's reaction to the standstill has important implications for the achievement of the target-based equilibrium and for the potential collapse of the market price. This paper examines OPEC's policy options in the tolerance trap and reveals that the optional policy in order to break this impasse and move closer to the equilibrium point is gradually to reduce output and not to flood the market. (Author)

Transitions in Lava Emplacement Recorded in the Deccan Traps Sequence (India)

Science.gov (United States)

Vanderkluysen, L.; Self, S.; Jay, A. E.; Sheth, H. C.; Clarke, A. B.

2015-12-01

Transitions in the style of lava flow emplacement are recognized in the stratigraphic sequence of several mafic large igneous provinces (LIPs), including the Etendeka (Namibia), the Faeroe Islands (North Atlantic LIP), the Ethiopian Traps, and the Deccan Traps (India). These transitions, from units dominated by meter-sized pāhoehoe toes and lobes to those dominated by inflated sheet lobes tens to hundreds of meters in width and meters to tens of meters in height, seems to be a fundamental feature of LIP emplacement. In the Deccan, this volcanological transition is thought to coincide with deeper changes to the volcano-magmatic system expressed, notably, in the trace element and isotopic signature of erupted flows. We investigated this transition in the Deccan Traps by logging eight sequences along the Western Ghats, an escarpment in western India where the Deccan province is thickest and best exposed. The Deccan province, which once covered ~1 million km2 of west-central India, is subdivided in eleven chemo-stratigraphic formations in the type sections of the Western Ghats. Where the lower Deccan formations are exposed, we found that as much as 65% of the exposed thickness (below the Khandala Formation) is made up of sheet lobes, from 40% in the Bhimashankar Formation to 75% in the Thakurvadi Formation. Near the bottom of the sequence, 25% of the Neral Formation is composed of sheet lobes ≥15 m in thickness. On this basis, the traditional view that inflated sheet lobes are an exclusive feature of the upper part of the stratigraphy must be challenged. Several mechanisms have been proposed to explain the development of compound flows and inflated sheet lobes, involving one or more of the following factors: underlying slope, varying effusion rate, and source geometry. Analogue experiments are currently under way to test the relative influence of each of these factors in the development of different lava flow morphologies in LIPs.

Geological techniques utilized in trap Spring Field discovery, Railroad Valley, Nye County, Nevada

Energy Technology Data Exchange (ETDEWEB)

Dolly, E.D.

1980-01-01

The trap at Eagle Springs Field is a combination stratigraphic truncation-subcrop-fault trap. Production occurs from matrix and fracture porosity in reservoirs in the Sheep Pass Formation (Cretaceous and Eocene) and the Garrett Ranch volcanic group (Oligocene). Probably the most unique feature about the field is that the production occurs from the highest position on the lowermost fault block at the basin margin. On the adjacent higher fault blocks the reservoir beds were removed by erosion during the basin and range orogenic event. The position of the truncated edge of the lower Tertiary reservoir units is controlled by the fault pattern at the margin of the valley-basin Graben. Detailed geomorphic studies indicated that this fault pattern may be identified at the surface. Regional geomorphic mapping of fault patterns was conducted to localize areas with possible subcrop truncation patterns similar to Eagle Springs Field. 20 references.

Litho-stratigraphic and Hydrogeological Evaluation of Groundwater ...

African Journals Online (AJOL)

ADOWIE PERE

2015-10-30

://www.ajol.info/index.php/jasem http://www.bioline.org.br/ja. Litho-stratigraphic and Hydrogeological Evaluation of Groundwater System in Parts of. Benin Metropolis, Benin City Nigeria: The Key to Groundwater Sustainability.

Aeolian sedimentary processes at the Bagnold Dunes, Mars: Implications for modern dune dynamics and sedimentary structures in the aeolian stratigraphic record of Mars

Science.gov (United States)

Ewing, Ryan C.; Bridges, Nathan T.; Sullivan, Rob; Lapotre, Mathieu G. A.; Fischer, Woodward W.; Lamb, Mike P.; Rubin, David M.; Lewis, Kevin W.; Gupta, Sanjeev

2016-04-01

Wind-blown sand dunes are ubiquitous on the surface of Mars and are a recognized component of the martian stratigraphic record. Our current knowledge of the aeolian sedimentary processes that determine dune morphology, drive dune dynamics, and create aeolian cross-stratification are based upon orbital studies of ripple and dune morphodynamics, rover observations of stratification on Mars, Earth analogs, and experimental and theoretical studies of sand movement under Martian conditions. In-situ observations of sand dunes (informally called the Bagnold Dunes) by Curiosity Rover in Gale Crater, Mars provide the first opportunity to make observations of dunes from the grain-to-dune scale thereby filling the gap in knowledge between theory and orbital observations and refining our understanding of the martian aeolian stratigraphic record. We use the suite of cameras on Curiosity, including Navigation Camera (Navcam), Mast Camera (Mastcam) and Mars Hand Lens Imager (MAHLI), to make observations of the Bagnold Dunes. Measurements of sedimentary structures are made where stereo images are available. Observations indicate that structures generated by gravity-driven processes on the dune lee slopes, such as grainflow and grainfall, are similar to the suite of aeolian sedimentary structures observed on Earth and should be present and recognizable in Mars' aeolian stratigraphic record. Structures formed by traction-driven processes deviate significantly from those found on Earth. The dune hosts centimeter-scale wind ripples and large, meter-scale ripples, which are not found on Earth. The large ripples migrate across the depositional, lee slopes of the dune, which implies that these structures should be present in Mars' stratigraphic record and may appear similar to compound-dune stratification.The Mars Science Laboratory Curiosity Rover Team is acknowledged for their support of this work.

The historical dynamics of social-ecological traps.

Science.gov (United States)

Boonstra, Wiebren J; de Boer, Florianne W

2014-04-01

Environmental degradation is a typical unintended outcome of collective human behavior. Hardin's metaphor of the "tragedy of the commons" has become a conceived wisdom that captures the social dynamics leading to environmental degradation. Recently, "traps" has gained currency as an alternative concept to explain the rigidity of social and ecological processes that produce environmental degradation and livelihood impoverishment. The trap metaphor is, however, a great deal more complex compared to Hardin's insight. This paper takes stock of studies using the trap metaphor. It argues that the concept includes time and history in the analysis, but only as background conditions and not as a factor of causality. From a historical-sociological perspective this is remarkable since social-ecological traps are clearly path-dependent processes, which are causally produced through a conjunction of events. To prove this point the paper conceptualizes social-ecological traps as a process instead of a condition, and systematically compares history and timing in one classic and three recent studies of social-ecological traps. Based on this comparison it concludes that conjunction of social and environmental events contributes profoundly to the production of trap processes. The paper further discusses the implications of this conclusion for policy intervention and outlines how future research might generalize insights from historical-sociological studies of traps.

Controlling factors of stratigraphic occurrences of fine-grained turbidites: Examples from the Japanese waters

Science.gov (United States)

Ikehara, K.

2017-12-01

Fine-grained turbidite has been used for subaqueous paleoseismology, and has been recognized from shallow- to deep-water environments around the Japanese islands. Stratigraphic occurrence of fine-grained turbidites in the deepest Beppu Bay, south Japan, with its water depth of 75 m suggest clear influence of sea-level changes. Turbidite frequency was high during the post glacial sea-level rising and last 2.7 ka, and was low during the Holocene maximum sea-level highstand (5.3-2.7 ka). Retreat and progress of coastal delta front of the nearby river might affect the sediment supply to the deepest basin. On the other hand, fine-grained turbidites found in the forearc basins ( 3500 and 4500 m in water depths) and trench floor ( 6000 m in water depth) along the southern Ryukyu arc have no clear relation with sea-level changes. Sediment and bathymetric characteristics suggest that origin of these fine-grained turbidites is Taiwan. Remarkable tectonic uplift of Taiwanese coast with small mountainous rivers and narrow shelf may produce the continuous supply of fine-grained turbidites in this area. The Japan Trench floor composes of a series of small basins reflecting subducting horst-graben structure of the Pacific Plate. Each small basin acts as a natural sediment trap receiving the earthquake-induced turbidity currents. Thick fine-grained turbidites are also occurred in the small basins in the Japan Trench floor ( 7500 m in water depth). These are most likely induced by huge earthquakes along the Japan Trench. Thus, their stratigraphic occurrences might have close relation with recurrence of huge earthquakes in the past.

SDAR 1.0 a New Quantitative Toolkit for Analyze Stratigraphic Data

Science.gov (United States)

Ortiz, John; Moreno, Carlos; Cardenas, Andres; Jaramillo, Carlos

2015-04-01

Since the foundation of stratigraphy geoscientists have recognized that data obtained from stratigraphic columns (SC), two dimensional schemes recording descriptions of both geological and paleontological features (e.g., thickness of rock packages, grain size, fossil and lithological components, and sedimentary structures), are key elements for establishing reliable hypotheses about the distribution in space and time of rock sequences, and ancient sedimentary environmental and paleobiological dynamics. Despite the tremendous advances on the way geoscientists store, plot, and quantitatively analyze sedimentological and paleontological data (e.g., Macrostrat [http://www.macrostrat.org/], Paleobiology Database [http://www.paleodb.org/], respectively), there is still a lack of computational methodologies designed to quantitatively examine data from a highly detailed SCs. Moreover, frequently the stratigraphic information is plotted "manually" using vector graphics editors (e.g., Corel Draw, Illustrator), however, this information although store on a digital format, cannot be used readily for any quantitative analysis. Therefore, any attempt to examine the stratigraphic data in an analytical fashion necessarily takes further steps. Given these issues, we have developed the sofware 'Stratigraphic Data Analysis in R' (SDAR), which stores in a database all sedimentological, stratigraphic, and paleontological information collected from a SC, allowing users to generate high-quality graphic plots (including one or multiple features stored in the database). SDAR also encompasses quantitative analyses helping users to quantify stratigraphic information (e.g. grain size, sorting and rounding, proportion of sand/shale). Finally, given that the SDAR analysis module, has been written in the open-source high-level computer language "R graphics/statistics language" [R Development Core Team, 2014], it is already loaded with many of the crucial features required to accomplish basic and

The Role of Electron Transport and Trapping in MOS Total-Dose Modeling

International Nuclear Information System (INIS)

Flament, O.; Fleetwood, D.M.; Leray, J.L.; Paillet, P.; Riewe, L.C.; Winokur, P.S.

1999-01-01

Deep and shallow electron traps form in irradiated thermal SiO 2 as a natural response to hole transport and trapping. The density and stability of these defects are discussed, as are their implications for total-dose modeling

Characteristics of the Paleozoic slope break system and its control on stratigraphic-lithologic traps: An example from the Tarim Basin, western China

Directory of Open Access Journals (Sweden)

Hao Liu

2015-07-01

Full Text Available Based on comprehensive analyses of seismic and log data, this study indicates that mainly four widespread angular to minor angular unconformities (Tg8, Tg51, Tg5 and Tg3 were formed during the Paleozoic. Through the interpretation of structural unconformities, calculation of eroded thickness, correction of palaeo-water depth and compaction and compilation of the Early Paleozoic structural maps, the Early Paleozoic slope break belt (geomorphologic unit of the Tarim Basin is subdivided into uplift area, subaqueous uplift area, rift slope break belt, flexure slope break belt (slope belt, depression area and deep basin area. Palaeogeomorphology of the Cambrian-Early Ordovician was approximately in EW trend within which three tectonic units including the Tabei Palaeo-uplift, the northern Depressional Belt and the southern Palaeo-uplift developed respectively and are grouped into two slope break systems namely as the Tabei Palaeo-uplift and the southern Palaeo-uplift. These tectonic units obviously control the deposition of isolated platform, open platform, restricted platform and deep basin. Influenced by extrusion in the Mid-Late Ordovician, the southern and northern subaqueous uplifts gradually elevated and then were eroded. Resultantly two slope break systems developed, namely as the northern and central Palaeo-uplifts which obviously controlled the deposition of provenance area, isolated platform, mixed continental shelf, slope and basin facies. The intensive extrusion of the Mid-Late Ordovician leads to significant tectonic deformation of the Tarim Basin: large area of uplifting and erosion and development of EW trending anticline and syncline. Deposition of shore, tidal flat, delta, shallow marine clastics and deep marine facies is obviously controlled by the Tabei, the southern and the Tadong Palaeo-uplifts. Slope break systems control development of stratigraphic unconformity and thus truncation and onlap unconformity zones become favorable

Towards a wire-mediated coupling of trapped ions

Science.gov (United States)

Clark, Robert; Lee, Tony; Daniilidis, Nikos; Sankaranarayanan, S.; Häffner, Hartmut

2008-03-01

Most schemes for ion trap quantum computation rely upon the exchange of information between ion-qubits in the same trap region, mediated by their shared vibrational mode. An alternative way to achieve this coupling is via the image charges induced in a conducting wire that connects different traps. This was shown to be theoretically possible by Heinzen and Wineland in 1990, but some important practical questions have remained unaddressed. Among these are how the presence of such a wire modifies the motional frequencies and heating rates of trapped ions. We thus have realized this system as a 1 mm-scale planar segmented rf ion trap combined with an electrically floating gold wire of 25 microns diameter and length 1 cm. This wire is placed close to trapped ions using a set of piezoelectric nanopositioners. We present here experimental measurements of the motional frequencies and heating rates of a single trapped calcium ion as the wire is moved from 3.0 mm to 0.2 mm away from the ion. We discuss the implications of these results for achieving wire-mediated coupling in the present apparatus, as well as in future improved setups.

Stratigraphic architecture of a fluvial-lacustrine basin-fill succession at Desolation Canyon, Uinta Basin, Utah: Reference to Walthers’ Law and implications for the petroleum industry

Science.gov (United States)

Ford, Grace L.; David R. Pyles,; Dechesne, Marieke

2016-01-01

A continuous window into the fluvial-lacustrine basin-fill succession of the Uinta Basin is exposed along a 48-mile (77-kilometer) transect up the modern Green River from Three Fords to Sand Wash in Desolation Canyon, Utah. In ascending order the stratigraphic units are: 1) Flagstaff Limestone, 2) lower Wasatch member of the Wasatch Formation, 3) middle Wasatch member of the Wasatch Formation, 4) upper Wasatch member of the Wasatch Formation, 5) Uteland Butte member of the lower Green River Formation, 6) lower Green River Formation, 7) Renegade Tongue of the lower Green River Formation, 8) middle Green River Formation, and 9) the Mahogany oil shale zone marking the boundary between the middle and upper Green River Formations. This article uses regional field mapping, geologic maps, photographs, and descriptions of the stratigraphic unit including: 1) bounding surfaces, 2) key upward stratigraphic characteristics within the unit, and 3) longitudinal changes along the river transect. This information is used to create a north-south cross section through the basin-fill succession and a detailed geologic map of Desolation Canyon. The cross section documents stratigraphic relationships previously unreported and contrasts with earlier interpretations in two ways: 1) abrupt upward shifts in the stratigraphy documented herein, contrast with the gradual interfingering relationships proposed by Ryder et al., (1976) and Fouch et al., (1994), 2) we document fluvial deposits of the lower and middle Wasatch to be distinct and more widespread than previously recognized. In addition, we document that the Uteland Butte member of the lower Green River Formation was deposited in a lacustrine environment in Desolation Canyon.

Early evolution of the southern margin of the Neuquén Basin, Argentina: Tectono-stratigraphic implications for rift evolution and exploration of hydrocarbon plays

Science.gov (United States)

D'Elia, Leandro; Bilmes, Andrés; Franzese, Juan R.; Veiga, Gonzalo D.; Hernández, Mariano; Muravchik, Martín

2015-12-01

Long-lived rift basins are characterized by a complex structural and tectonic evolution. They present significant lateral and vertical stratigraphic variations that determine diverse basin-patterns at different timing, scale and location. These issues cause difficulties to establish facies models, correlations and stratal stacking patterns of the fault-related stratigraphy, specially when exploration of hydrocarbon plays proceeds on the subsurface of a basin. The present case study corresponds to the rift-successions of the Neuquén Basin. This basin formed in response to continental extension that took place at the western margin of Gondwana during the Late Triassic-Early Jurassic. A tectono-stratigraphic analysis of the initial successions of the southern part of the Neuquén Basin was carried out. Three syn-rift sequences were determined. These syn-rift sequences were located in different extensional depocentres during the rifting phases. The specific periods of rifting show distinctly different structural and stratigraphic styles: from non-volcanic to volcanic successions and/or from continental to marine sedimentation. The results were compared with surface and subsurface interpretations performed for other depocentres of the basin, devising an integrated rifting scheme for the whole basin. The more accepted tectono-stratigraphic scheme that assumes the deposits of the first marine transgression (Cuyo Cycle) as indicative of the onset of a post-rift phase is reconsidered. In the southern part of the basin, the marine deposits (lower Cuyo Cycle) were integrated into the syn-rift phase, implying the existence of different tectonic signatures for Cuyo Cycle along the basin. The rift climax becomes younger from north to south along the basin. The post-rift initiation followed the diachronic ending of the main syn-rift phase throughout the Neuquén Basin. Thus, initiation of the post-rift stage started in the north and proceeded towards the south, constituting a

Stratigraphic, regional unconformity analysis and potential petroleum plays of East Siberian Sea Basin

Science.gov (United States)

Karpov, Yury; Stoupakova, Antonina; Suslova, Anna; Agasheva, Mariia

2017-04-01

The East Siberian Sea basin (ESSB) one of the most unexplored part of the Russian Arctic shelf, extending for over 1000 km from New Siberian Islands archipelago to Wrangel Island. This region is considered as a region with probable high petroleum potential. Within the ESSB several phases of orogeny are recognized [1]: Elsmerian orogeny in Early Devonian, Early Brooks orogeny in Early Cretaceous, Late Brooks orogeny in Late Cretaceous. Two generations of the basins could be outlined. Both of these generations are controlled by the basement domains [1]: Paleozoic (post-Devonian) to Mesozoic basins preserved north of the Late Mesozoic frontal thrusts; Aptian-Albian to Quaternary basins, postdating the Verkhoyansk-Brookian orogeny, and evolving mainly over the New-Siberian-Chukchi Fold Belt. Basin is filled with siliclastic sediments and in the deepest depocentres sediments thickness exceeds 8-10 km in average. Seismic data was interpreted using methods of seismic stratigraphy. Finally, main seismic horizons were indicated and each horizon follows regional stratigraphic unconformities: mBU - in base of Cenozoic, BU - in base of Upper Cretaceous, LCU - in base of Cretaceous, JU - in middle of Jurassic, F - in top of Basement. In ESSB, we can identify Permian, Triassic, Jurassic, Cretaceous, Paleogene and Neogene seismic stratigraphy complexes. Perspective structures, investigated in ESSB were founded out by comparing seismogeological cross-sections with explored analogs in other onshore and offshore basins [2, 3, 4]. The majority of structures could be connected with stratigraphic and fault traps. The most perspective prospects are probably connected with grabens and depressions, where thickness of sediments exceed 10 km. Reservoirs in ESSB are proposed by regional geological explorations on New Siberian Islands Archipelago and Wrangel Island. Potential seals are predominantly assigned to Jurassic and Cretaceous periods. Thick clinoform units of various geometry and

The Bero Volganic Group: New Lithological, Stratigraphic, and Geochemical Data of this Extension of the Parana-Etendeka Igneous Province into SW Angola with Implications

Science.gov (United States)

Marsh, J.; Swart, R.

2015-12-01

The Bero Volcanic Group, an extension of the Etendeka-Paraná Igneous Province into SW Angola, forms the eroded basement to the on-shore Namibe Basin, an Early Cretaceous-Cenozoic terrestrial and marine sedimentary sequence. The igneous suite outcrops between latitudes 14.68o and 15.25o S and comprises quartz latite rheoignimbrites/lavas, tholeiitic basaltic lavas, pyroclastic/volcaniclastic deposits, minor aeolian sandstones, and mafic tholeiitic dykes and gabbroic sheets. Quartz latite lithologies dominate. In the Rio Bero area in the S quartz latites are underlain by several thin flows of basalt interbedded with, and underlain by, thin discontinuous lenses of aeolian sandstone. This sequence is consistent with the general stratigraphic sequence in the northern Etendeka of Namibia. To the N basalts and aeolian sandstones are absent and the quartz latites lie directly on Precambrian basement rocks in places. To date, data for a quartz latite correlated with a Chapecó rhyolites of the Paraná are available from only one locality in Angola. This study's wider sampling and major and trace element and radiogenic isotope analysis reveals the following: (1) all mafic rocks are high-Ti, the lavas being equivalent to the Khumiba/Urubici type; (2) mafic dykes cutting the quartz latites having affinities to the Paranapanema-Ribeira mafic lavas; (3) five quartz latite geochemical types are present, three of which are known from Etendeka/Paraná (Sarusas/Guarapuava, Khoraseb/Ourinhos and Ventura) and their stratigraphic relationships in Angola are consistent with those in the Etendeka and Paraná; (4) their Angolan occurrence significantly extends the area covered by, and potential eruptive volumes of, these silicic types; (5) two other quartz latite types are unknown in the Etendeka and Paraná and are probably products of low-volume, local eruptions. The Chinguau type is geochemically similar to the low-Ti quartz lalites of the southern Etendeka but has lower Epsilon Nd

Stratigraphic inversion of pre-stack multicomponent data; Inversion stratigraphique multicomposante avant sommation

Energy Technology Data Exchange (ETDEWEB)

Agullo, Y.

2005-09-15

This thesis present the extension of mono-component seismic pre-stack data stratigraphical inversion method to multicomponent data, with the objective of improving the determination of reservoir elastic parameters. In addiction to the PP pressure waves, the PS converted waves proved their interest for imaging under gas clouds; and their potential is highly significant for the characterization of lithologies, fluids, fractures... Nevertheless the simultaneous use ol PP and PS data remains problematic because of their different the time scales. To jointly use the information contained in PP and PS data, we propose a method in three steps first, mono-component stratigraphic inversions of PP then PS data; second, estimation of the PP to PS time conversion law; third, multicomponent stratigraphic inversion. For the second point, the estimation of the PP to PS conversion law is based on minimizing the difference between the S impedances obtained from PP and PS mono-component stratigraphic inversion. The pre-stack mono-component stratigraphic inversions was adapted to the case of multicomponent data by leaving each type of data in its own time scale in order to avoid the distortion of the seismic wavelet. The results obtained on a realistic synthetic PP-PS case show on one hand that determining PP to PS conversion law (from the mono-component inversion results) is feasible, and on the other hand that the joint inversion of PP and PS data with this conversion law improves the results compared to the mono-component inversion ones. Although this is presented within the framework of the PP and PS multi-component data, the developed methodology adapts directly to PP and SS data for example. (author)

Neutrophil extracellular traps in patients with pulmonary tuberculosis

NARCIS (Netherlands)

van der Meer, Anne Jan; Zeerleder, Sacha; Blok, Dana C.; Kager, Liesbeth M.; Lede, Ivar O.; Rahman, Wahid; Afroz, Rumana; Ghose, Aniruddha; Visser, Caroline E.; Zahed, Abu Shahed Md; Husain, Md Anwar; Alam, Khan Mashrequl; Barua, Pravat Chandra; Hassan, Mahtabuddin; Tayab, Md Abu; Dondorp, Arjen M.; van der Poll, Tom

2017-01-01

Tuberculosis is a devastating infectious disease causing many deaths worldwide. Recent investigations have implicated neutrophil extracellular traps (NETs) in the host response to tuberculosis. The aim of the current study was to obtain evidence for NETs release in the circulation during human

A gene-trap strategy identifies quiescence-induced genes in ...

Indian Academy of Sciences (India)

PRAKASH KUMAR G

and Walsh 1996). The balance between proliferation and ... In three lines, insertion occurred in genes previously implicated in the control of quiescence, i.e. ...... arrest-specific traps fall into different functional classes, such as cytoskeletal ...

Investigation of SAGD steam trap control in two and three dimensions

Energy Technology Data Exchange (ETDEWEB)

Edmunds, N. R. [Clearwater Engineering, AB (Canada)

1998-12-31

Steam trap production control has been traditionally recommended for steam-assisted gravity drainage (SAGD) operations. This study examines the relationship between producing steam trap subcool settings and related parameters of interest such as fluid level, pressure, production rate, and profitability for a prototype Athabasca reservoir. Study results indicate that the steam trap dynamics are far more complex than hitherto imagined, that 3-D simulations predict significantly lower production rates than 2-D simulations, and that these variations have implications for all aspects of SAGD engineering, including process optimization, production operations and performance analysis. 10 refs., 2 tabs., 15 figs.

Subsurface geology of the Lusi region: preliminary results from a comprehensive seismic-stratigraphic study.

Science.gov (United States)

Moscariello, Andrea; Do Couto, Damien; Lupi, Matteo; Mazzini, Adriano

2016-04-01

We investigate the subsurface data of a large sector in the Sidoarjo district (East Java, Indonesia) where the sudden catastrophic Lusi eruption started the 26th May 2006. Our goal is to understand the stratigraphic and structural features which can be genetically related to the surface manifestations of deep hydrothermal fluids and thus allow us to predict possible future similar phenomena in the region. In the framework of the Lusi Lab project (ERC grant n° 308126) we examined a series of densely spaced 2D reflection commercial seismic lines This allowed the reconstruction of the lateral variability of key stratigraphic horizons as well as the main tectonic features. In particular, we shed light on the deep structure of the Watukosek fault system and the associated fracture corridors crossing the entire stratigraphic successions. To the South-West, when approaching the volcanic complex, we could identify a clear contrast in seismic facies between chaotic volcanoclastic wedges and clastic-prone sedimentary successions as well as between the deeper stratigraphic units consisting of carbonates and lateral shales units. The latter show possible ductile deformation associated to fault-controlled diapirism which control in turns deformation of overlying stratigraphic units and deep geo-fluids circulation. Large collapse structures recognized in the study area (e.g. well PRG-1) are interpreted as the results of shale movement at depth. Similarly to Lusi, vertical deformation zones ("pipes"), likely associated with deeply rooted strike-slip systems seem to be often located at the interface between harder carbonate rocks forming isolated build ups and the laterally nearby clastic (shale-prone)-units. The mechanisms of deformation of structural features (strike vs dip slip systems) which may affect either the basement rock or the overlying deeper stratigraphic rocks is also being investigated to understand the relationship between deep and shallower (i.e. meteoric) fluid

Sequence Stratigraphic Appraisal: Coastal Swamp Depobelt In The ...

African Journals Online (AJOL)

Mid-Lower Miocene Agbada sedimentary intercalations of “AB” Field in the coastal swamp depobelt, Western Niger-Delta, were evaluated to determine their sequence stratigraphic character. The analysis was based on a combination of data sets including logs of six wells to describe lithic variations of the Agbada Formation ...

Ecohydrological implications of aeolian sediment trapping by sparse vegetation in drylands

Science.gov (United States)

Gonzales, Howell B.; Ravi, Sujith; Li, Junran; Sankey, Joel B.

2018-01-01

Aeolian processes are important drivers of ecosystem dynamics in drylands, and important feedbacks exist among aeolian – hydrological processes and vegetation. The trapping of wind-borne sediments by vegetation may result in changes in soil properties beneath the vegetation, which, in turn, can alter hydrological and biogeochemical processes. Despite the relevance of aeolian transport to ecosystem dynamics, the interactions between aeolian transport and vegetation in shaping dryland landscapes where sediment distribution is altered by relatively rapid changes in vegetation composition such as shrub encroachment, is not well understood. Here, we used a computational fluid dynamics (CFD) modeling framework to investigate the sediment trapping efficiencies of vegetation canopies commonly found in a shrub-grass ecotone in the Chihuahuan Desert (New Mexico, USA) and related the results to spatial heterogeneity in soil texture and infiltration measured in the field. A CFD open-source software package was used to simulate aeolian sediment movement through three-dimensional architectural depictions of Creosote shrub (Larrea tridentata) and Black Grama grass (Bouteloua eriopoda) vegetation types. The vegetation structures were created using a computer-aided design software (Blender), with inherent canopy porosities, which were derived using LIDAR (Light Detection and Ranging) measurements of plant canopies. Results show that considerable heterogeneity in infiltration and soil grain size distribution exist between the microsites, with higher infiltration and coarser soil texture under shrubs. Numerical simulations also indicate that the differential trapping of canopies might contribute to the observed heterogeneity in soil texture. In the early stages of encroachment, the shrub canopies, by trapping coarser particles more efficiently, might maintain higher infiltration rates leading to faster development of the microsites (among other factors) with enhanced ecological

Stratigraphic model deposit Ofi Inf SDZ-2X A1, Jun in block in Orinoco Oil belt

International Nuclear Information System (INIS)

Martinez, E.; Sandoval, D.

2010-01-01

This work is about the Stratigraphic model deposit O fi I nf SDZ-2X A1, Junin block in Orinoco Oil belt.This model was based on a chrono stratigraphic interpretation and was defined the correlation between the main and secondary surfaces. The wells of the study area pass through the Cambrian, Cretaceous and Miocene sediments. The last is more interesting for the study because of the stratigraphic and sand body surface presence

A method of reconstructing complex stratigraphic surfaces with multitype fault constraints

Science.gov (United States)

Deng, Shi-Wu; Jia, Yu; Yao, Xing-Miao; Liu, Zhi-Ning

2017-06-01

The construction of complex stratigraphic surfaces is widely employed in many fields, such as petroleum exploration, geological modeling, and geological structure analysis. It also serves as an important foundation for data visualization and visual analysis in these fields. The existing surface construction methods have several deficiencies and face various difficulties, such as the presence of multitype faults and roughness of resulting surfaces. In this paper, a surface modeling method that uses geometric partial differential equations (PDEs) is introduced for the construction of stratigraphic surfaces. It effectively solves the problem of surface roughness caused by the irregularity of stratigraphic data distribution. To cope with the presence of multitype complex faults, a two-way projection algorithm between threedimensional space and a two-dimensional plane is proposed. Using this algorithm, a unified method based on geometric PDEs is developed for dealing with multitype faults. Moreover, the corresponding geometric PDE is derived, and an algorithm based on an evolutionary solution is developed. The algorithm proposed for constructing spatial surfaces with real data verifies its computational efficiency and its ability to handle irregular data distribution. In particular, it can reconstruct faulty surfaces, especially those with overthrust faults.

Stratigraphic Profiles for Selected Hanford Site Seismometer Stations and Other Locations

Energy Technology Data Exchange (ETDEWEB)

Last, George V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2014-02-01

Stratigraphic profiles were constructed for eight selected Hanford Site seismometer stations, five Hanford Site facility reference locations, and seven regional three-component broadband seismometer stations. These profiles provide interpretations of the subsurface layers to support estimation of ground motions from past earthquakes, and the prediction of ground motions from future earthquakes. In most cases these profiles terminated at the top of the Wanapum Basalt, but at selected sites profiles were extended down to the top of the crystalline basement. The composite one-dimensional stratigraphic profiles were based primarily on previous interpretations from nearby boreholes, and in many cases the nearest deep borehole is located kilometers away.

Fossil preservation and the stratigraphic ranges of taxa

Science.gov (United States)

Foote, M.; Raup, D. M.

1996-01-01

The incompleteness of the fossil record hinders the inference of evolutionary rates and patterns. Here, we derive relationships among true taxonomic durations, preservation probability, and observed taxonomic ranges. We use these relationships to estimate original distributions of taxonomic durations, preservation probability, and completeness (proportion of taxa preserved), given only the observed ranges. No data on occurrences within the ranges of taxa are required. When preservation is random and the original distribution of durations is exponential, the inference of durations, preservability, and completeness is exact. However, reasonable approximations are possible given non-exponential duration distributions and temporal and taxonomic variation in preservability. Thus, the approaches we describe have great potential in studies of taphonomy, evolutionary rates and patterns, and genealogy. Analyses of Upper Cambrian-Lower Ordovician trilobite species, Paleozoic crinoid genera, Jurassic bivalve species, and Cenozoic mammal species yield the following results: (1) The preservation probability inferred from stratigraphic ranges alone agrees with that inferred from the analysis of stratigraphic gaps when data on the latter are available. (2) Whereas median durations based on simple tabulations of observed ranges are biased by stratigraphic resolution, our estimates of median duration, extinction rate, and completeness are not biased.(3) The shorter geologic ranges of mammalian species relative to those of bivalves cannot be attributed to a difference in preservation potential. However, we cannot rule out the contribution of taxonomic practice to this difference. (4) In the groups studied, completeness (proportion of species [trilobites, bivalves, mammals] or genera [crinoids] preserved) ranges from 60% to 90%. The higher estimates of completeness at smaller geographic scales support previous suggestions that the incompleteness of the fossil record reflects loss of

40Ar/39Ar dating and paleo-magnetism of traps from Ethiopia, Deccan and Siberia

International Nuclear Information System (INIS)

Hofmann, C.

1997-01-01

Recent studies have shown that major flood basalt provinces have been emplaced as short events (∼ 1 Myr), more or less synchronous with climatic crises and mass extinctions. We present new geochronologic ( 40 Ar/ 39 Ar) and magneto-stratigraphic results for the Ethiopian traps, one of the last remaining flood basalts for which little of such data were available. The ages obtained in a 2000 m thick section are indistinguishable. Moreover, magneto-stratigraphy reveals a simple 3-chron reverse-normal-reverse sequence. Although magnetic chrons cannot be yet unambiguously identified, there is more likelihood for the normal sub-chron in the main basaltic pile to correspond to 11N, supporting a brief duration (less than 1.5 Ma). The Ethiopian traps erupted near 30 Ma at or near the time of the cold and dry climate, major Antarctic ice sheet advance, and the largest sea-level drop in the Tertiary. Bhandari et al. (GRL, 1995) have discovered inter-traps sediments with a triple iridium anomaly in a series of seven basaltic lava flows in the Kutch area of the North Western Deccan traps of India. Plagioclases from three flows above the iridium bearing sediments yield 39 Ar/ 40 Ar plateau ages near 65.0 Ma: these flows have unambiguously reversed magnetic polarity interpreted as chron 29R. As a preliminary summary, evidence of the KTB asteroid impact is confirmed in the Deccan traps, showing that they are coeval events in a general sense (in a Ma long window) though clearly with vastly different time constants. This is compatible with paleontologic evidence of two scales of extinctions, one quasi-instantaneous and the other on the order of 10 5 to 10 6 yrs. Clearly, the impact cannot have caused trap eruptions. On the other hand, the exact age and significance of the lower flows more altered remains to be analyzed further as they pertained to the much debated question of duration of Deccan trap volcanism. (author)

Intrinsic electron traps in atomic-layer deposited HfO{sub 2} insulators

Energy Technology Data Exchange (ETDEWEB)

Cerbu, F.; Madia, O.; Afanas' ev, V. V.; Houssa, M.; Stesmans, A. [Laboratory of Semiconductor Physics, Department of Physics and Astronomy, University of Leuven, 3001 Leuven (Belgium); Andreev, D. V. [Laboratory of Semiconductor Physics, Department of Physics and Astronomy, University of Leuven, 3001 Leuven (Belgium); Bauman Moscow State Technical University—Kaluga Branch, 248000 Kaluga, Moscow obl. (Russian Federation); Fadida, S.; Eizenberg, M. [Department of Materials Science and Engineering, Technion-Israel Institute of Technology, 32000 Haifa (Israel); Breuil, L. [imec, 3001 Leuven (Belgium); Lisoni, J. G. [imec, 3001 Leuven (Belgium); Institute of Physics and Mathematics, Faculty of Science, Universidad Austral de Chile, Valdivia (Chile); Kittl, J. A. [Laboratory of Semiconductor Physics, Department of Physics and Astronomy, University of Leuven, 3001 Leuven (Belgium); Advanced Logic Lab, Samsung Semiconductor, Inc., Austin, 78754 Texas (United States); Strand, J.; Shluger, A. L. [Department of Physics and Astronomy, University College London, London WC1E 6BT (United Kingdom)

2016-05-30

Analysis of photodepopulation of electron traps in HfO{sub 2} films grown by atomic layer deposition is shown to provide the trap energy distribution across the entire oxide bandgap. The presence is revealed of two kinds of deep electron traps energetically distributed at around E{sub t} ≈ 2.0 eV and E{sub t} ≈ 3.0 eV below the oxide conduction band. Comparison of the trapped electron energy distributions in HfO{sub 2} layers prepared using different precursors or subjected to thermal treatment suggests that these centers are intrinsic in origin. However, the common assumption that these would implicate O vacancies cannot explain the charging behavior of HfO{sub 2}, suggesting that alternative defect models should be considered.

Automated recognition of stratigraphic marker shales from geophysical logs in iron ore deposits

Science.gov (United States)

Silversides, Katherine; Melkumyan, Arman; Wyman, Derek; Hatherly, Peter

2015-04-01

The mining of stratiform ore deposits requires a means of determining the location of stratigraphic boundaries. A variety of geophysical logs may provide the required data but, in the case of banded iron formation hosted iron ore deposits in the Hamersley Ranges of Western Australia, only one geophysical log type (natural gamma) is collected for this purpose. The information from these logs is currently processed by slow manual interpretation. In this paper we present an alternative method of automatically identifying recurring stratigraphic markers in natural gamma logs from multiple drill holes. Our approach is demonstrated using natural gamma geophysical logs that contain features corresponding to the presence of stratigraphically important marker shales. The host stratigraphic sequence is highly consistent throughout the Hamersley and the marker shales can therefore be used to identify the stratigraphic location of the banded iron formation (BIF) or BIF hosted ore. The marker shales are identified using Gaussian Processes (GP) trained by either manual or active learning methods and the results are compared to the existing geological interpretation. The manual method involves the user selecting the signatures for improving the library, whereas the active learning method uses the measure of uncertainty provided by the GP to select specific examples for the user to consider for addition. The results demonstrate that both GP methods can identify a feature, but the active learning approach has several benefits over the manual method. These benefits include greater accuracy in the identified signatures, faster library building, and an objective approach for selecting signatures that includes the full range of signatures across a deposit in the library. When using the active learning method, it was found that the current manual interpretation could be replaced in 78.4% of the holes with an accuracy of 95.7%.

Stratigraphic relations and hydrologic properties of the Paintbrush Tuff (PTn) hydrologic unit, Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Moyer, T.C.; Geslin, J.K.; Flint, L.E.

1996-01-01

Yucca Mountain is being investigated as a potential site for a high- level nuclear waste repository. The intent of this study was to clarify stratigraphic relations within the Paintbrush Tuff (PTn) unit at Yucca Mountain in order to better understand vertical and lateral variations in hydrologic properties as they relate to the lithologic character of these rocks. This report defines informal stratigraphic units within the PTn interval, demonstrates their lateral continuity in the Yucca Mountain region, describes later and vertical variations within them, and characterizes their hydrologic properties and importance to numerical flow and transport models. We present tables summarizing the depth to stratigraphic contacts in cored borehole studies, and unit descriptions and correlations in 10 measured sections

Stratigraphic relations and hydrologic properties of the Paintbrush Tuff (PTn) hydrologic unit, Yucca Mountain, Nevada

Energy Technology Data Exchange (ETDEWEB)

Moyer, T.C.; Geslin, J.K. [Science Applications International Corp., Golden, CO (United States); Flint, L.E. [U.S. Geological Survey, Yucca Mountain Project, Mercury, NV (United States)

1996-08-01

Yucca Mountain is being investigated as a potential site for a high- level nuclear waste repository. The intent of this study was to clarify stratigraphic relations within the Paintbrush Tuff (PTn) unit at Yucca Mountain in order to better understand vertical and lateral variations in hydrologic properties as they relate to the lithologic character of these rocks. This report defines informal stratigraphic units within the PTn interval, demonstrates their lateral continuity in the Yucca Mountain region, describes later and vertical variations within them, and characterizes their hydrologic properties and importance to numerical flow and transport models. We present tables summarizing the depth to stratigraphic contacts in cored borehole studies, and unit descriptions and correlations in 10 measured sections.

{sup 40}Ar/{sup 39}Ar dating and paleo-magnetism of traps from Ethiopia, Deccan and Siberia; Datation {sup 40}Ar/{sup 39}Ar et paleomagnetisme des traps d'Ethiopie, du Deccan et de Siberie

Energy Technology Data Exchange (ETDEWEB)

Hofmann, C

1997-01-01

Recent studies have shown that major flood basalt provinces have been emplaced as short events ({approx} 1 Myr), more or less synchronous with climatic crises and mass extinctions. We present new geochronologic ({sup 40}Ar/{sup 39}Ar) and magneto-stratigraphic results for the Ethiopian traps, one of the last remaining flood basalts for which little of such data were available. The ages obtained in a 2000 m thick section are indistinguishable. Moreover, magneto-stratigraphy reveals a simple 3-chron reverse-normal-reverse sequence. Although magnetic chrons cannot be yet unambiguously identified, there is more likelihood for the normal sub-chron in the main basaltic pile to correspond to 11N, supporting a brief duration (less than 1.5 Ma). The Ethiopian traps erupted near 30 Ma at or near the time of the cold and dry climate, major Antarctic ice sheet advance, and the largest sea-level drop in the Tertiary. Bhandari et al. (GRL, 1995) have discovered inter-traps sediments with a triple iridium anomaly in a series of seven basaltic lava flows in the Kutch area of the North Western Deccan traps of India. Plagioclases from three flows above the iridium bearing sediments yield {sup 39}Ar/{sup 40}Ar plateau ages near 65.0 Ma: these flows have unambiguously reversed magnetic polarity interpreted as chron 29R. As a preliminary summary, evidence of the KTB asteroid impact is confirmed in the Deccan traps, showing that they are coeval events in a general sense (in a Ma long window) though clearly with vastly different time constants. This is compatible with paleontologic evidence of two scales of extinctions, one quasi-instantaneous and the other on the order of 10{sup 5} to 10{sup 6} yrs. Clearly, the impact cannot have caused trap eruptions. On the other hand, the exact age and significance of the lower flows more altered remains to be analyzed further as they pertained to the much debated question of duration of Deccan trap volcanism. (author)

A preliminary guidebook for identifying stratigraphic contacts at the Nevada Test Site

International Nuclear Information System (INIS)

Pawloski, G.A.; McKague, H.L.; Wagoner, J.L.; McKinnis, W.B.

1992-01-01

Lithologic variation, regional depositional trends, and the lack of written guidelines have resulted in inconsistencies in the recognition of stratigraphic contacts in drill holes at the Nevada Test Site (NTS). Stratigraphic identification, based on mineralogy of discrete samples, can be augmented by geophysical logs and downhole movies to more accurately and consistently locate contacts between units. Criteria are established for locating the base of the Pahute Mesa ash-flow tuff, the top of the Ammonia Tanks ash-flow tuff, the top of the Ammonia Tanks bedded tuff, and the top and the base of the Rainier Mesa Tuff

A three-dimensional stratigraphic model for aggrading submarine channels based on laboratory experiments, numerical modeling, and sediment cores

Science.gov (United States)

Limaye, A. B.; Komatsu, Y.; Suzuki, K.; Paola, C.

2017-12-01

Turbidity currents deliver clastic sediment from continental margins to the deep ocean, and are the main driver of landscape and stratigraphic evolution in many low-relief, submarine environments. The sedimentary architecture of turbidites—including the spatial organization of coarse and fine sediments—is closely related to the aggradation, scour, and lateral shifting of channels. Seismic stratigraphy indicates that submarine, meandering channels often aggrade rapidly relative to lateral shifting, and develop channel sand bodies with high vertical connectivity. In comparison, the stratigraphic architecture developed by submarine, braided is relatively uncertain. We present a new stratigraphic model for submarine braided channels that integrates predictions from laboratory experiments and flow modeling with constraints from sediment cores. In the laboratory experiments, a saline density current developed subaqueous channels in plastic sediment. The channels aggraded to form a deposit with a vertical scale of approximately five channel depths. We collected topography data during aggradation to (1) establish relative stratigraphic age, and (2) estimate the sorting patterns of a hypothetical grain size distribution. We applied a numerical flow model to each topographic surface and used modeled flow depth as a proxy for relative grain size. We then conditioned the resulting stratigraphic model to observed grain size distributions using sediment core data from the Nankai Trough, offshore Japan. Using this stratigraphic model, we establish new, quantitative predictions for the two- and three-dimensional connectivity of coarse sediment as a function of fine-sediment fraction. Using this case study as an example, we will highlight outstanding challenges in relating the evolution of low-relief landscapes to the stratigraphic record.

Bio-derived fuels may ease the regeneration of diesel particulate traps

Energy Technology Data Exchange (ETDEWEB)

E. Coda Zabetta; M. Hupa; S. Niemi [Aabo Akademi Process Chemistry Centre, Turku (Finland)

2006-12-15

Particulate is the most problematic emission from diesel engines. To comply with environmental regulations, these engines are often equipped with particulate traps, which must be regenerated frequently for the sake of efficiency. The regeneration is commonly achieved by rising the temperature in the trap till the particulate self-ignites. However, this method implies energy losses and thermal shocks in the trap. Alternatively, catalysts and additives have been recently considered for reducing the ignition temperature of particulate, but these techniques suffer from poisoning and undesirable byproducts. The present experimental study shows that the ignition temperature of particulate from seed-derived oils (SO) and from blends of SO with diesel fuel oil (DO) can be lower than that of particulate from neat DO. If substantiated by more extensive studies, such finding could have noteworthy implications on the future of fuels and traps. Short communication. 8 refs., 3 figs., 2 tabs.

Production of antihydrogen at reduced magnetic field for anti-atom trapping

CERN Document Server

Andresen, G.B.; Boston, A.; Bowe, P.D.; Cesar, C.L.; Chapman, S.; Charlton, M.; Chartier, M.; Deutsch, A.; Fajans, J.; Fujiwara, M.C.; Funakoshi, R.; Gill, D.R.; Gomberoff, K.; Hangst, J.S.; Hayano, R.S.; Hydomako, R.; Jenkins, M.J.; Jorgensen, L.V.; Kurchaninov, L.; Madsen, N.; Nolan, P.; Olchanski, K.; Olin, A.; Page, R.D.; Povilus, A.; Robicheaux, F.; Sarid, E.; Silveira, D.M.; Storey, J.W.; Thompson, R.I.; van der Werf, D.P.; Wurtele, J.S.; Yamazaki, Y.

2008-01-01

We have demonstrated production of antihydrogen in a 1$,$T solenoidal magnetic field. This field strength is significantly smaller than that used in the first generation experiments ATHENA (3$,$T) and ATRAP (5$,$T). The motivation for using a smaller magnetic field is to facilitate trapping of antihydrogen atoms in a neutral atom trap surrounding the production region. We report the results of measurements with the ALPHA (Antihydrogen Laser PHysics Apparatus) device, which can capture and cool antiprotons at 3$,$T, and then mix the antiprotons with positrons at 1$,$T. We infer antihydrogen production from the time structure of antiproton annihilations during mixing, using mixing with heated positrons as the null experiment, as demonstrated in ATHENA. Implications for antihydrogen trapping are discussed.

Paleomagnetism and 40Ar / 39Ar Geochronology of Yemeni Oligocene volcanics: Implications for timing and duration of Afro-Arabian traps and geometry of the Oligocene paleomagnetic field

Science.gov (United States)

Riisager, Peter; Knight, Kim B.; Baker, Joel A.; Ukstins Peate, Ingrid; Al-Kadasi, Mohamed; Al-Subbary, Abdulkarim; Renne, Paul R.

2005-09-01

A combined paleomagnetic and 40Ar / 39Ar study was carried out along eight stratigraphically overlapping sections in the Oligocene Afro-Arabian flood volcanic province in Yemen (73 sites). The composite section covers the entire volcanic stratigraphy in the sampling region and represents five polarity zones that are correlated to the geomagnetic polarity time scale based on 40Ar / 39Ar ages from this and previous studies. The resulting magnetostratigraphy is similar to that of the conjugate margin in Ethiopia. The earliest basaltic volcanism took place in a reverse polarity chron that appears to correspond to C11r, while the massive rhyolitic ignimbrite eruptions correlated to ash layers in Oligocene Indian Ocean sediment 2700 km away from the Afro-Arabian traps, appear to have taken place during magnetochron C11n. The youngest ignimbrite was emplaced during magnetochron C9n. Both 40Ar / 39Ar and paleomagnetic data suggest rapid Red Sea. By analyzing Afro-Arabian paleomagnetic data in conjunction with contemporaneous paleomagnetic poles available from different latitudes we argue that the Oligocene paleomagnetic field was dominated by the axial dipole with insignificant non-dipole field contributions.

Tectonic-stratigraphic evolution of mini-basins and salt provinces of Espirito Santo Basin-Brazil; Analise da evolucao tectono sedimentar de mini-bacias e provincias de sal da Bacia do Espirito Santo

Energy Technology Data Exchange (ETDEWEB)

Ferreira Neto, Walter Dias; Fernandes, Flavio Luis [Petroleum Geoscience Technology Ltda. (PGT), Rio de Janeiro, RJ (Brazil); Mohriak, Webster [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil); Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, RJ (Brazil)

2008-07-01

The Espirito Santo Basin integrates the group of basins along the eastern Brazilian continental margin. It is located between 18 deg and 21 deg S, encompassing an area of approximately 220,000 km{sup 2}, onshore and offshore the Espirito Santo State. Its geological limit with the Campos Basin to the south is defined by a Precambrian basement high (Vitoria Arch), and its northern limit with the Mucuri Basin is defined by a geopolitical limit. The study of salt tectonics processes in the Espirito Santo Basin allowed the deformational analysis and interpretation of the chronological evolution of the mini-basins developed between salt diapirs. We observe an intrinsic relationship between halokinesis and creation of subsidence troughs that may be important for trapping hydrocarbon reservoirs, and consequently form oil and gas accumulations in this portion of the basin. This geodynamics evolution of these structures is marked by a strong linkage between salt movement and coeval sedimentation in the interdomal basins, forming structures and stratigraphic traps that may constitute important aspects for the petroleum geology. (author)

Effects of oxide traps, interface traps, and ''border traps'' on metal-oxide-semiconductor devices

International Nuclear Information System (INIS)

Fleetwood, D.M.; Winokur, P.S.; Reber, R.A. Jr.; Meisenheimer, T.L.; Schwank, J.R.; Shaneyfelt, M.R.; Riewe, L.C.

1993-01-01

We have identified several features of the 1/f noise and radiation response of metal-oxide-semiconductor (MOS) devices that are difficult to explain with standard defect models. To address this issue, and in response to ambiguities in the literature, we have developed a revised nomenclature for defects in MOS devices that clearly distinguishes the language used to describe the physical location of defects from that used to describe their electrical response. In this nomenclature, ''oxide traps'' are simply defects in the SiO 2 layer of the MOS structure, and ''interface traps'' are defects at the Si/SiO 2 interface. Nothing is presumed about how either type of defect communicates with the underlying Si. Electrically, ''fixed states'' are defined as trap levels that do not communicate with the Si on the time scale of the measurements, but ''switching states'' can exchange charge with the Si. Fixed states presumably are oxide traps in most types of measurements, but switching states can either be interface traps or near-interfacial oxide traps that can communicate with the Si, i.e., ''border traps'' [D. M. Fleetwood, IEEE Trans. Nucl. Sci. NS-39, 269 (1992)]. The effective density of border traps depends on the time scale and bias conditions of the measurements. We show the revised nomenclature can provide focus to discussions of the buildup and annealing of radiation-induced charge in non-radiation-hardened MOS transistors, and to changes in the 1/f noise of MOS devices through irradiation and elevated-temperature annealing

Sequence stratigraphy in the middle Ordovician shale successions, mid-east Korea: Stratigraphic variations and preservation potential of organic matter within a sequence stratigraphic framework

Science.gov (United States)

Byun, Uk Hwan; Lee, Hyun Suk; Kwon, Yi Kyun

2018-02-01

The Jigunsan Formation is the middle Ordovician shale-dominated transgressive succession in the Taebaeksan Basin, located in the eastern margin of the North China platform. The total organic carbon (TOC) content and some geochemical properties of the succession exhibit a stratigraphically distinct distribution pattern. The pattern was closely associated with the redox conditions related to decomposition, bulk sedimentation rate (dilution), and productivity. To explain the distinct distribution pattern, this study attempted to construct a high-resolution sequence stratigraphic framework for the Jigunsan Formation. The shale-dominated Jigunsan Formation comprises a lower layer of dark gray shale, deposited during transgression, and an upper layer of greenish gray siltstone, deposited during highstand and falling stage systems tracts. The concept of a back-stepped carbonate platform is adopted to distinguish early and late transgressive systems tracts (early and late TST) in this study, whereas the highstand systems tracts and falling stage systems tracts can be divided by changes in stacking patterns from aggradation to progradation. The late TST would be initiated on a rapidly back-stepping surface of sediments and, just above the surface, exhibits a high peak in TOC content, followed by a gradually upward decrease. This trend of TOC distribution in the late TST continues to the maximum flooding surface (MFS). The perplexing TOC distribution pattern within the late TST most likely resulted from both a gradual reduction in productivity during the late TST and a gradual increase in dilution effect near the MFS interval. The reduced production of organic matter primarily incurred decreasing TOC content toward the MFS when the productivity was mainly governed by benthic biota because planktonic organisms were not widespread in the Ordovician. Results of this study will help improve the understanding of the source rock distribution in mixed carbonate

Interactions Between Stratigraphy and Interfacial Properties on Flow and Trapping in Geologic Carbon Storage

Science.gov (United States)

Liang, Bo; Clarens, Andres F.

2018-01-01

Gas leakage from geologic carbon storage sites could undermine the long-term goal of reducing emissions to the atmosphere and negatively impact groundwater resources. Despite this, there remain uncertainties associated with the transport processes that would govern this leakage. These stem from the complex interaction between governing forces (e.g., gravitational, viscous, and capillary), the heterogeneous nature of the porous media, and the characteristic length scales of these leakage events, all of which impact the CO2 fluid flow processes. Here we assessed how sub-basin-scale horizons in porous media could impact the migration and trapping of a CO2 plume. A high-pressure column packed with two layers of sand with different properties (e.g., grain size and wettability) was used to create a low-contrast stratigraphic horizon. CO2 in supercritical or liquid phase was injected into the bottom of the column under various conditions (e.g., temperature, pressure, and capillary number) and the transport of the resulting plume was recorded using electrical resistivity. The results show that CO2 trapping was most strongly impacted by shifting the wettability balance to mixed-wet conditions, particularly for residual saturation. A 16% increase in the cosine of the contact angle for a mixed-wet sand resulted in nearly twice as much residual trapping. Permeability contrast, pressure, and temperature also impacted the residual saturation but to a lesser extent. Flow rate affected the dynamics of saturation profile development, but the effect is transient, suggesting that the other effects observed here could apply to a broad range of leakage conditions.

Evaluation of monitoring traps with novel bait for navel orangeworm (Lepidoptera: Pyralidae) in California almond and pistachio orchards.

Science.gov (United States)

Nay, Justin E; Peterson, Elonce M; Boyd, Elizabeth A

2012-08-01

Experiments conducted in three almond, Prunus dulcis (Rosales: Rosaceae), orchards and three pistachio, Pistacia vera (Sapindales: Anicardiaceae), orchards in 2009 and 2010, and determined that sticky bottom wing traps baited with ground pistachio mummies, or a combination of ground pistachio plus ground almond mummies, trapped more adult female navel orangeworm, Amyelois transitella (Walker) (Lepidoptera: Pyralidae), than did traps baited with ground almond mummies alone. During both years of this study, 2.9 and 1.8 more moths were caught in traps baited with pistachio mummies compared with traps baited with almond mummies in almond orchards and pistachio orchards, respectively. Also, traps located in pistachio orchards caught 5.9 and 8.3 times more navel orangeworm than were trapped from almond orchards in 2009 and 2010, respectively. Implications for use of this novel baited trap in almond and pistachio orchard integrated pest management programs are discussed.

Shrew trap efficiency

DEFF Research Database (Denmark)

Gambalemoke, Mbalitini; Mukinzi, Itoka; Amundala, Drazo

2008-01-01

We investigated the efficiency of four trap types (pitfall, Sherman LFA, Victor snap and Museum Special snap traps) to capture shrews. This experiment was conducted in five inter-riverine forest blocks in the region of Kisangani. The total trapping effort was 6,300, 9,240, 5,280 and 5,460 trap......, our results indicate that pitfall traps are the most efficient for capturing shrews: not only do they have a higher efficiency (yield), but the taxonomic diversity of shrews is also higher when pitfall traps are used....

Revised Cretaceous and Tertiary stratigraphic nomenclature in the Colville Basin, Northern Alaska

Science.gov (United States)

Mull, Charles G.; Houseknecht, David W.; Bird, Kenneth J.

2003-01-01

A revised stratigraphic nomenclature is proposed for Cretaceous and Tertiary geologic units of the central and western North Slope of Alaska. This revised nomenclature is a simplified and broadly applicable scheme suitable for a suite of digital geologic quadrangle maps being prepared jointly by the U.S. Geological Survey and the Alaska Department of Natural Resources, Division of Geological and Geophysical Surveys and Division of Oil and Gas. This revised nomenclature scheme is a simplification of a complex stratigraphic terminology that developed piecemeal during five decades of geologic investigations of the North Slope. It is based on helicopter-supported geologic field investigations incorporating information from high-resolution aerial photography, satellite imagery, paleontology, reflection seismic records, and sequence stratigraphic concepts. This revised nomenclature proposes the abandonment of the Colville Group; demotion of the Nanushuk Group to formation status; abandonment of six formations (Kukpowruk, Tuktu, Grandstand, Corwin, Chandler, and Ninuluk); revision of four formations (Sagavanirktok, Prince Creek, Schrader Bluff, and Seabee); elevation of the Tuluvak Tongue of the Prince Creek Formation to formation status; revision of two members (Franklin Bluffs Member and Sagwon Member of the Sagavanirktok Formation); abandonment of eight members or tongues (Kogosukruk, Rogers Creek, Barrow Trail, Sentinel Hill, Ayiyak, Shale Wall, Niakogon, and Killik); and definition of one new member (White Hills Member of the Sagavanirktok Formation).

Determination of Heat Capacity of Yucca Mountain Stratigraphic Layers

International Nuclear Information System (INIS)

T. Hadgu; C. Lum; J.E. Bean

2006-01-01

The heat generated from the radioactive waste to be placed in the proposed geologic repository at Yucca Mountain, Nevada, will affect the thermal-hydrology of the Yucca Mountain stratigraphic layers. In order to assess the effect of the movement of repository heat into the fractured rocks accurate determination of thermodynamic and hydraulic properties is important. Heat capacity is one of the properties that are required to evaluate energy storage in the fractured rock. Rock-grain heat capacity, the subject of this study, is the heat capacity of the solid part of the rock. Yucca Mountain consists of alternating lithostratigraphic units of welded and non-welded ash-flow tuff, mainly rhyolitic in composition and displaying varying degrees of vitrification and alteration. A number of methods exist that can be used to evaluate heat capacity of the stratigraphic layers that consist of different compositions. In this study, the mineral summation method has been used to quantify the heat capacity of the stratigraphic layers based on Kopp's rule. The mineral summation method is an addition of the weighted heat capacity of each mineral found in a specific layer. For this study the weighting was done based on the mass percentage of each mineral in the layer. The method utilized a mineralogic map of the rocks at the Yucca Mountain repository site. The Calico Hills formation and adjacent bedded tuff layers display a bimodal mineral distribution of vitric and zeolitic zones with differing mineralogies. Based on this bimodal distribution in zeolite abundance, the boundary between the vitric and zeolitic zones was selected to be 15% zeolitic abundance. Thus, based on the zeolite abundance, subdivisions have been introduced to these layers into ''vitric'' and ''zeolitic'' zones. Heat capacity values have been calculated for these layers both as ''layer average'' and ''zone average''. The heat capacity determination method presented in this report did not account for spatial

Characterization of sediment trapped by macroalgae on a Hawaiian reef flat

Science.gov (United States)

Stamski, Rebecca E.; Field, Michael E.

2006-01-01

Reef researchers studying community shifts in the balance between corals and fleshy macroalgae have noted that algae are often covered with sediment. This study characterizes sediment trapping by macroalgae within a Hawaiian reef habitat and constrains the controls on this process. Sediment-laden macroalgae were sampled and macroalgal cover was assessed on a wide (˜1 km) reef flat off south-central Molokai. Macroalgae trapped a mean of 1.26 (±0.91 SD) grams of sediment per gram of dry weight biomass and that sediment was dominantly terrigenous mud (59% by weight). It was determined that biomass, as a proxy for algal size, and morphology were not strict controls on the sediment trapping process. Over 300 metric tons of sediment were estimated to be retained by macroalgae across 5.75 km 2 of reef flat (54 g m -2), suggesting that this process is an important component of sediment budgets. In addition, understanding the character of sediment trapped by macroalgae may help constrain suspended sediment flux and has implications for nutrient dynamics in reef flat environments.

Topographic Growth, the Development of Rivers and Implications for the Marine Stratigraphic Record in SE Asia (Invited)

Science.gov (United States)

Clift, P. D.; Zheng, H.

2013-12-01

The sediments accumulating in the marginal seas of Southeast Asia are largely delivered from the major rivers that flow from the eastern flank of the Tibetan Plateau. At the regional scale the rate of sediment delivery is controlled by the intensity of the summer monsoon, but in individual deltas the composition of sediment and rates of sedimentation are also affected by headwater capture. Recent data now indicate that significant transfer drainage between rivers occurred around the end of the Oligocene-early Miocene (~24 Ma). This key period reflects the start of significant uplift in southeastern Tibet, coupled with extension and subsidence in the marginal seas of eastern Asia driven by the rollback of the Pacific plate. U-Pb ages of zircon sand grains in the Yangtze River show that this system was close to its present configuration before 23 Ma, correlating with large-scale change in the Red River during the latter part of the Oligocene. At the same time, the Irrawaddy loses its connection with the Yarlung Tsangpo, which dates back to shortly after India-Asia collision. The Yarlung Tsangpo together with the Indus appears to be unique in forming in the collisional suture between Asia (or an intraoceanic arc) and India shortly after 50 Ma. Once these two rivers are established in the suture zone it is impossible to disrupt their flow as a result of tectonically driven uplift, but it is only in Southwest Asia that the marine record would span the entire Cenozoic history of uplift and erosion, as preserved in the Indus Fan. In contrast, the more gradual tilting of Eastern Asia towards the east through the Cenozoic has resulted in the large-scale disruption noted in the deltas. Diversion of large volumes of clastic sediment from one delta to another has implications for how we interpret the deep-sea sediment record in each location and is of commercial interest in hydrocarbon exploration in changing the availability of reservoir sands on continental margins in ways

Stratigraphic and tectonic revision of Cerro Olivo Complex located of Southeastern of Uruguay

International Nuclear Information System (INIS)

Masquelin, E.

2004-01-01

This paper presents a stratigraphic and tectonic revision of Cerro Olivo Complex, located in the Southeastern part of the Uruguayan Predevonian Shield. This informal lithostratigraphic unit constitutes the country rock for the emplacement of late-orogenic granitoids, during Neoproterozoic to Cambrian times. This unit groups all the lithodemes affected by deformation and metamorphism. Recent studies indicate the presence of straight gneisses of quartzo-feldspathic composition in the coast of Maldonado Department. These rocks were interpreted as the result of intense deformation in high temperature. These tectonites base a new stratigraphic insight for the complex. They allow their lithotypes to be organized by petrotectonic features, being a function of PT conditions for every last strain process [es

Malaria and protective behaviours: is there a malaria trap?

Science.gov (United States)

Berthélemy, Jean-Claude; Thuilliez, Josselin; Doumbo, Ogobara; Gaudart, Jean

2013-06-13

In spite of massive efforts to generalize efficient prevention, such as insecticide-treated mosquito nets (ITN) or long-lasting insecticidal nets (LLINs), malaria remains prevalent in many countries and ITN/LLINs are still only used to a limited extent. This study proposes a new model for malaria economic analysis by combining economic epidemiology tools with the literature on poverty traps. A theoretical model of rational protective behaviour in response to malaria is designed, which includes endogenous externalities and disease characteristics. Survey data available for Uganda provide empirical support to the theory of prevalence-elastic protection behaviours, once endogeneity issues related to epidemiology and poverty are solved. Two important conclusions emerge from the model. First, agents increase their protective behaviour when malaria is more prevalent in a society. This is consistent with the literature on "prevalence-elastic behaviour". Second, a 'malaria trap' defined as the result of malaria reinforcing poverty while poverty reduces the ability to deal with malaria can theoretically exist and the conditions of existence of the malaria trap are identified. These results suggest the possible existence of malaria traps, which provides policy implications. Notably, providing ITN/LLINs at subsidized prices is not sufficient. To be efficient an ITN/LLINs dissemination campaigns should include incentive of the very poor for using ITN/LLINs.

Magnetic traps with a sperical separatrix: Tornado traps

International Nuclear Information System (INIS)

Peregood, B.P.; Lehnert, B.

1979-11-01

A review is given on the features of magnetic traps with a spherical separatrix, with special emphesis on Tornado spiral coil configurations. The confinement and heating of static plasmas in Tornado traps is treated, including the topology of the magnetic field structure, the magneto-mechanical properties of the magnetic coil system, as well as the particle orbits and plasma behaviour in these traps. In additio, the mode of rotating plasma operation by crossed electric and magnetic fields is being described. The results of experiments on static and rotating plasmas are summarized, and conclusions are drawn about future possibilities of Tornado traps for the creation and containment of hot plasmas. (author)

Magnetic traps with a spherical separatrix: Tornado traps

International Nuclear Information System (INIS)

Peregood, B.P.; Lehnert, B.

1981-01-01

A review is given on the features of magnetic traps with a spherical separatrix, with special emphasis on Tornado spiral coil configurations. The confinement and heating of static plasms in Tornado traps is treated, including the topology of the magnetic field structure, the magneto-mechanical properties of the magnetic coil system, as well as the particle orbits and plasma behaviour in these traps. In addition, the mode of rotating plasma operation by crossed electric and magnetic fields is described. The results of experiments on static and rotating plasmas are summarized, and conclusions are drawn about future possibilities of Tornado traps in the creation and containment of hot plasmas. (orig.)

Revised geochronology, correlation, and dinosaur stratigraphic ranges of the Santonian-Maastrichtian (Late Cretaceous) formations of the Western Interior of North America.

Science.gov (United States)

Fowler, Denver Warwick

2017-01-01

Interbasinal stratigraphic correlation provides the foundation for all consequent continental-scale geological and paleontological analyses. Correlation requires synthesis of lithostratigraphic, biostratigraphic and geochronologic data, and must be periodically updated to accord with advances in dating techniques, changing standards for radiometric dates, new stratigraphic concepts, hypotheses, fossil specimens, and field data. Outdated or incorrect correlation exposes geological and paleontological analyses to potential error. The current work presents a high-resolution stratigraphic chart for terrestrial Late Cretaceous units of North America, combining published chronostratigraphic, lithostratigraphic, and biostratigraphic data. 40Ar / 39Ar radiometric dates are newly recalibrated to both current standard and decay constant pairings. Revisions to the stratigraphic placement of most units are slight, but important changes are made to the proposed correlations of the Aguja and Javelina formations, Texas, and recalibration corrections in particular affect the relative age positions of the Belly River Group, Alberta; Judith River Formation, Montana; Kaiparowits Formation, Utah; and Fruitland and Kirtland formations, New Mexico. The stratigraphic ranges of selected clades of dinosaur species are plotted on the chronostratigraphic framework, with some clades comprising short-duration species that do not overlap stratigraphically with preceding or succeeding forms. This is the expected pattern that is produced by an anagenetic mode of evolution, suggesting that true branching (speciation) events were rare and may have geographic significance. The recent hypothesis of intracontinental latitudinal provinciality of dinosaurs is shown to be affected by previous stratigraphic miscorrelation. Rapid stepwise acquisition of display characters in many dinosaur clades, in particular chasmosaurine ceratopsids, suggests that they may be useful for high resolution biostratigraphy.

50 CFR 697.19 - Trap limits and trap tag requirements for vessels fishing with lobster traps.

Science.gov (United States)

2010-10-01

... vessels fishing with lobster traps. 697.19 Section 697.19 Wildlife and Fisheries FISHERY CONSERVATION AND... requirements for vessels fishing with lobster traps. (a) Trap limits for vessels fishing or authorized to fish... management area designation certificate or valid limited access American lobster permit specifying one or...

MIGRATION TRAPS IN DISKS AROUND SUPERMASSIVE BLACK HOLES

International Nuclear Information System (INIS)

Bellovary, Jillian M.; Low, Mordecai-Mark Mac; McKernan, Barry; Ford, K. E. Saavik

2016-01-01

Accretion disks around supermassive black holes (SMBHs) in active galactic nuclei (AGNs) contain stars, stellar mass black holes, and other stellar remnants, which perturb the disk gas gravitationally. The resulting density perturbations exert torques on the embedded masses causing them to migrate through the disk in a manner analogous to planets in protoplanetary disks. We determine the strength and direction of these torques using an empirical analytic description dependent on local disk gradients, applied to two different analytic, steady-state disk models of SMBH accretion disks. We find that there are radii in such disks where the gas torque changes sign, trapping migrating objects. Our analysis shows that major migration traps generally occur where the disk surface density gradient changes sign from positive to negative, around 20–300R g , where R g  = 2GM/c 2 is the Schwarzschild radius. At these traps, massive objects in the AGN disk can accumulate, collide, scatter, and accrete. Intermediate mass black hole formation is likely in these disk locations, which may lead to preferential gap and cavity creation at these radii. Our model thus has significant implications for SMBH growth as well as gravitational wave source populations

Tectonic-stratigraphic evolution of Cumuruxatiba Basin - Brazil; Evolucao tectono-estratigrafica da Bacia de Cumuruxatiba

Energy Technology Data Exchange (ETDEWEB)

Lobato, Gustavo; Fernandes, Flavio L.; Silva, Eric Zagotto; Ferreira Neto, Walter Dias [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE). Lab. de Modelagem Multidisciplinar de Bacias Sedimentares; Ribeiro, Juliana [Agencia Nacional do Petroleo, Gas Natural e Biocombustiveis (ANP), Brasilia, DF (Brazil)

2008-07-01

In recent years, the exploratory interest on Cumuruxatiba Basin has been inconstant, with modest discoveries of oil. Aiming to deepen the geological knowledge of the basin and in order to attract the interest of oil companies, the ANP (National Agency of Petroleum, Natural Gas and Biofuels) signed contract with COPPE/UFRJ for carrying out an analysis basin project. The project was developed by the Basin Analysis Multidisciplinary Modeling Laboratory (Lab2M/UFRJ) in the period 2006/2007, and was with the main objective outline the main structural and seismo-stratigraphic features of the basin, and in an integrated and multidisciplinary way, build a model of its sedimentation and tectono-stratigraphic evolution. This paper presents the results of the regional seismic mapping, aided by well and potential methods data. The stratigraphic succession the basin has been divided into genetic units (UN-B, UN-C e UN-D) corresponding to second order depositional sequences, they are: UN-B, corresponding by a rift and sag-rift siliciclastic deposits, plus the Aptian evaporitic deposits; UN-C, characterized by carbonatic deposits, and shelf related sediments; and UN-D, corresponding by a final transgressive (siliciclastic) - regressive (mix) cycle, between Cenomanian and actual days. (author)

Cryogenic surface ion traps

International Nuclear Information System (INIS)

Niedermayr, M.

2015-01-01

Microfabricated surface traps are a promising architecture to realize a scalable quantum computer based on trapped ions. In principle, hundreds or thousands of surface traps can be located on a single substrate in order to provide large arrays of interacting ions. To this end, trap designs and fabrication methods are required that provide scalable, stable and reproducible ion traps. This work presents a novel surface-trap design developed for cryogenic applications. Intrinsic silicon is used as the substrate material of the traps. The well-developed microfabrication and structuring methods of silicon are utilized to create simple and reproducible traps. The traps were tested and characterized in a cryogenic setup. Ions could be trapped and their life time and motional heating were investigated. Long ion lifetimes of several hours were observed and the measured heating rates were reproducibly low at around 1 phonon per second at a trap frequency of 1 MHz. (author) [de

Artificial covering on trap nests improves the colonization of trap-nesting wasps

OpenAIRE

Taki, Hisatomo; Kevan, Peter G.; Viana, Blandina Felipe; Silva, Fabiana O.; Buck, Matthias

2008-01-01

Acesso restrito: Texto completo. p. 225-229 To evaluate the role that a trap-nest cover might have on sampling methodologies, the abundance of each species of trap-nesting Hymenoptera and the parasitism rate in a Canadian forest were compared between artificially covered and uncovered traps. Of trap tubes exposed at eight forest sites in six trap-nest boxes, 531 trap tubes were occupied and 1216 individuals of 12 wasp species of four predatory families, Vespidae (Eumeninae), Crabronidae...

Discriminating between antihydrogen and mirror-trapped antiprotons in a minimum-B trap

CERN Document Server

Amole, C; Ashkezari, M D; Baquero-Ruiz, M; Bertsche, W; Butler, E; Cesar, C L; Chapman, S; Charlton, M; Deller, A; Eriksson, S; Fajans, J; Friesen, T; Fujiwara, M C; Gill, D R; Gutierrez, A; Hangst, J S; Hardy, W N; Hayden, M E; Humphries, A J; Hydomako, R; Kurchaninov, L; Jonsell, S; Madsen, N; Menary, S; Nolan, P; Olchanski, K; Olin, A; Povilus, A; Pusa, P; Robicheaux, F; Sarid, E; Silveira, D M; So, C; Storey, J W; Thompson, R I; van der Werf, D P; Wurtele, J S

2012-01-01

Recently, antihydrogen atoms were trapped at CERN in a magnetic minimum (minimum-B) trap formed by superconducting octupole and mirror magnet coils. The trapped antiatoms were detected by rapidly turning off these magnets, thereby eliminating the magnetic minimum and releasing any antiatoms contained in the trap. Once released, these antiatoms quickly hit the trap wall, whereupon the positrons and antiprotons in the antiatoms annihilated. The antiproton annihilations produce easily detected signals; we used these signals to prove that we trapped antihydrogen. However, our technique could be confounded by mirror-trapped antiprotons, which would produce seemingly-identical annihilation signals upon hitting the trap wall. In this paper, we discuss possible sources of mirror-trapped antiprotons and show that antihydrogen and antiprotons can be readily distinguished, often with the aid of applied electric fields, by analyzing the annihilation locations and times. We further discuss the general properties of antipr...

Stable Trapping of Multielectron Helium Bubbles in a Paul Trap

Science.gov (United States)

Joseph, E. M.; Vadakkumbatt, V.; Pal, A.; Ghosh, A.

2017-06-01

In a recent experiment, we have used a linear Paul trap to store and study multielectron bubbles (MEBs) in liquid helium. MEBs have a charge-to-mass ratio (between 10^{-4} and 10^{-2} C/kg) which is several orders of magnitude smaller than ions (between 10^6 and 10^8 C/kg) studied in traditional ion traps. In addition, MEBs experience significant drag force while moving through the liquid. As a result, the experimental parameters for stable trapping of MEBs, such as magnitude and frequency of the applied electric fields, are very different from those used in typical ion trap experiments. The purpose of this paper is to model the motion of MEBs inside a linear Paul trap in liquid helium, determine the range of working parameters of the trap, and compare the results with experiments.

Earlier (late Pliocene) first appearance of the Caribbean reef-building coral Acropora palmata: Stratigraphic and evolutionary implications

Science.gov (United States)

McNeill, Donald F.; Budd, Ann F.; Borne, Pamela F.

1997-10-01

An integrated stratigraphic study of reefal deposits on the Caribbean side of the Isthmus of Panama (Limon, Costa Rica) has discovered a significantly earlier first appearance of the major reef-building coral Acropora palmata. A. palmata is here reported from the early late Pliocene, constrained in age to within the Gauss chron (ca. 3.6 2.6 Ma). This coral was previously thought to have originated in the earliest Pleistocene and has subsequently been used as a Quaternary marker throughout the Caribbean and the Bahamas. An earlier appearance in the southern Caribbean implies a diachronous first appearance datum relative to the northern Caribbean. This older age also places A. palmata well within the transition phase of a Pliocene (4 1 Ma) faunal turnover that was marked by widespread extinction and origination of Caribbean coral species. An early late Pliocene origination is coincident with formation of the Isthmus, climate reorganization, and frequent sea-level changes associated with onset of Northern Hemisphere glaciations. The rapid growth and accumulation rates that characterize A. palmata may therefore be adaptive to these fluctuating environmental conditions, enabling its success during the subsequent Pleistocene glacial cycles.

Venusian extended ejecta deposits as time-stratigraphic markers

Science.gov (United States)

Izenberg, Noam R.

1992-01-01

Use of impact crater ejects at time-stratigraphic markers was established during lunar geologic mapping efforts. The basic premise is that the deposition of impact ejecta, either by itself or mixed with impact-excavated material, is superimposed on a surface. The deposit becomes an observable, mappable unit produced in a single instant in geologic time. Up to two-thirds of Venus craters exhibit extended ejecta deposits. A reconnaissance survey of 336 craters (about 40 percent of the total population) was conducted. About half the craters examined were located in and around the Beta-Atla-Themis region, and half were spread over the western hemisphere of the planet. The survey was conducted using primarily C1-MIDR images. The preliminary survey shows: (1) of the 336 craters, 223 were found to have extended ejecta deposits. This proportion is higher than that found in other Venus crater databases by up to a factor of 2. (2) 53 percent of all extended ejecta craters were unambiguously superimposed on all volcanic and tectonic units. Crater Annia Faustina's associated parabolic ejecta deposit is clearly superimposed on volcanic flows coming from Gula Mons to the west. Parabola material from Faustina has covered the lava flows, smoothing the surface and reducing its specific backscatter cross section. The stratigraphy implies that the parabola material is the youngest observable unit in the region. (3) 12 percent of extended ejecta deposits are superimposed by volcanic materials. Crater Hwangcini has extended ejecta that has been covered by volcanic flows from a dome field to the northwest, implying that the volcanic units were emplaced subsequent to the ejecta deposit and are the youngest units in the locality. (4) It is difficult to determine the stratigraphic relationships of the remaining extended ejecta deposits in SAR at C1-MIDR resolution. Examination of higher resolution images and application of the other Magellan datasets in systematic manner should resolve

Correlating hydrogeostratification with geostratification from nuclear logging and geoelectric sounding in water impregnated traps

International Nuclear Information System (INIS)

Bardhan, M.

1977-01-01

Subsurface boundary conditions obtained through nuclear logging and geoelectric sounding were compared with the driller's log recorded in a number of boreholes drilled by employing modern down-the-hole hammer rig, to diagnose the relative merits of the methods and to portray the actual subsurface stratigraphic succession as well as hydrophysical conditions in saturated trap formations. It was observed that nuclear logging and resistivity sounding do not furnish the actual geostratigraphy due to lack of sufficient contrast in the relevant physical properties between successive lava flows, but reflects on the prevailing hydrostratigraphy. However, the informations thrown up by them are of immense technical value in guiding ground water development programme through sinking of wells in trappean terrians. It is shown that the horizontal correlation value of nuclear logging can be augmented by combining it with geoelectric sounding. This aids in enhancing the practical utility of nuclear logs in geohydrologic investigations. (author)

Proterozoic rifting and major unconformities in Rajasthan, and their implications for uranium mineralisation

International Nuclear Information System (INIS)

Sinha-Roy, S.

2004-01-01

Evolution of the Precambrian terrain in Rajasthan has taken place via crustal consolidation of the basement at ca. 2.9 Ga, its cratonisation at ca. 2.5 Ga, through protracted tectonostratigraphic evolution of the Proterozoic cover sequences, following repeated rifting and Wilson cycles in the Aravalli and Delhi foldbelts. Consequently, the Proterozoic rift basins are characterised by growth faults and pull-aparts, and multitier volcanose dimentary sequences that contain a number of unconformities and stratigraphic breaks. The Archaean basement of the Mewar terrain that witnessed end-Archaean K-magmatism and ductile shearing, led to the creation of a possible uranium province, namely uranium enriched basement. This province acted as the source of remobilised uranium and its concentration at suitable multilevel structural and stratigraphic traps within the Proterozoic rift basins to give rise to unconformity-related syngenetic uranium mineralisation. Late Neoproterozoic to Pan-African tectonothermal reworking of the basement rocks produced fracture zones and caused Na-metasomatism giving rise to albitite-related uranium mineralisation. Based on an analysis of Proterozoic rift kinematics and lithofacies characteristics, five possible uranium-enriched stratigraphic horizons have been identified in the Aravalli and its equivalent sequences as well as in the North Delhi foldbelt sequences. From a regional synthesis, ten possible uranium metallogenic events, spanning ca. 2.5-0.5 Ga, are recognised in Rajasthan. These uranium events have predictive value for delineation of target areas for exploration. (author)

Conditions for order and chaos in the dynamics of a trapped Bose-Einstein condensate in coordinate and energy space

Science.gov (United States)

Sakhel, Roger R.; Sakhel, Asaad R.; Ghassib, Humam B.; Balaz, Antun

2016-03-01

We investigate numerically conditions for order and chaos in the dynamics of an interacting Bose-Einstein condensate (BEC) confined by an external trap cut off by a hard-wall box potential. The BEC is stirred by a laser to induce excitations manifesting as irregular spatial and energy oscillations of the trapped cloud. Adding laser stirring to the external trap results in an effective time-varying trapping frequency in connection with the dynamically changing combined external+laser potential trap. The resulting dynamics are analyzed by plotting their trajectories in coordinate phase space and in energy space. The Lyapunov exponents are computed to confirm the existence of chaos in the latter space. Quantum effects and trap anharmonicity are demonstrated to generate chaos in energy space, thus confirming its presence and implicating either quantum effects or trap anharmonicity as its generator. The presence of chaos in energy space does not necessarily translate into chaos in coordinate space. In general, a dynamic trapping frequency is found to promote chaos in a trapped BEC. An apparent means to suppress chaos in a trapped BEC is achieved by increasing the characteristic scale of the external trap with respect to the condensate size.

Nematode-Trapping Fungi.

Science.gov (United States)

Jiang, Xiangzhi; Xiang, Meichun; Liu, Xingzhong

2017-01-01

Nematode-trapping fungi are a unique and intriguing group of carnivorous microorganisms that can trap and digest nematodes by means of specialized trapping structures. They can develop diverse trapping devices, such as adhesive hyphae, adhesive knobs, adhesive networks, constricting rings, and nonconstricting rings. Nematode-trapping fungi have been found in all regions of the world, from the tropics to Antarctica, from terrestrial to aquatic ecosystems. They play an important ecological role in regulating nematode dynamics in soil. Molecular phylogenetic studies have shown that the majority of nematode-trapping fungi belong to a monophyletic group in the order Orbiliales (Ascomycota). Nematode-trapping fungi serve as an excellent model system for understanding fungal evolution and interaction between fungi and nematodes. With the development of molecular techniques and genome sequencing, their evolutionary origins and divergence, and the mechanisms underlying fungus-nematode interactions have been well studied. In recent decades, an increasing concern about the environmental hazards of using chemical nematicides has led to the application of these biological control agents as a rapidly developing component of crop protection.

Characteristics of trapped electrons and electron traps in single crystals

International Nuclear Information System (INIS)

Budzinski, E.E.; Potter, W.R.; Potienko, G.; Box, H.C.

1979-01-01

Two additional carbohydrates are reported whose crystal structures trap electrons intermolecularly in single crystals x irradiated at low temperature, namely sucrose and rhamnose. Five carbohydrate and polyhydroxy compounds are now known which exhibit this phenomenon. The following characteristics of the phenomenon were investigated: (1) the hyperfine couplings of the electron with protons of the polarized hydroxy groups forming the trap; (2) the distances between these protons and the trapped electron; (3) the spin density of the electron at the protons and (4) the relative stabilities of the electron trapped in various crystal structures

Glaciotectonic deformation and reinterpretation of the Worth Point stratigraphic sequence: Banks Island, NT, Canada

Science.gov (United States)

Vaughan, Jessica M.; England, John H.; Evans, David J. A.

2014-05-01

Hill-hole pairs, comprising an ice-pushed hill and associated source depression, cluster in a belt along the west coast of Banks Island, NT. Ongoing coastal erosion at Worth Point, southwest Banks Island, has exposed a section (6 km long and ˜30 m high) through an ice-pushed hill that was transported ˜ 2 km from a corresponding source depression to the southeast. The exposed stratigraphic sequence is polydeformed and comprises folded and faulted rafts of Early Cretaceous and Late Tertiary bedrock, a prominent organic raft, Quaternary glacial sediments, and buried glacial ice. Three distinct structural domains can be identified within the stratigraphic sequence that represent proximal to distal deformation in an ice-marginal setting. Complex thrust sequences, interfering fold-sets, brecciated bedrock and widespread shear structures superimposed on this ice-marginally deformed sequence record subsequent deformation in a subglacial shear zone. Analysis of cross-cutting relationships within the stratigraphic sequence combined with OSL dating indicate that the Worth Point hill-hole pair was deformed during two separate glaciotectonic events. Firstly, ice sheet advance constructed the hill-hole pair and glaciotectonized the strata ice-marginally, producing a proximal to distal deformation sequence. A glacioisostatically forced marine transgression resulted in extensive reworking of the strata and the deposition of a glaciomarine diamict. A readvance during this initial stage redeformed the strata in a subglacial shear zone, overprinting complex deformation structures and depositing a glaciotectonite ˜20 m thick. Outwash channels that incise the subglacially deformed strata record a deglacial marine regression, whereas aggradation of glaciofluvial sand and gravel infilling the channels record a subsequent marine transgression. Secondly, a later, largely non-erosive ice margin overrode Worth Point, deforming only the most surficial units in the section and depositing a

MIGRATION TRAPS IN DISKS AROUND SUPERMASSIVE BLACK HOLES

Energy Technology Data Exchange (ETDEWEB)

Bellovary, Jillian M.; Low, Mordecai-Mark Mac; McKernan, Barry; Ford, K. E. Saavik [Department of Astrophysics, American Museum of Natural History, Central Park West at 79th Street, NY 10024 (United States)

2016-03-10

Accretion disks around supermassive black holes (SMBHs) in active galactic nuclei (AGNs) contain stars, stellar mass black holes, and other stellar remnants, which perturb the disk gas gravitationally. The resulting density perturbations exert torques on the embedded masses causing them to migrate through the disk in a manner analogous to planets in protoplanetary disks. We determine the strength and direction of these torques using an empirical analytic description dependent on local disk gradients, applied to two different analytic, steady-state disk models of SMBH accretion disks. We find that there are radii in such disks where the gas torque changes sign, trapping migrating objects. Our analysis shows that major migration traps generally occur where the disk surface density gradient changes sign from positive to negative, around 20–300R{sub g}, where R{sub g} = 2GM/c{sup 2} is the Schwarzschild radius. At these traps, massive objects in the AGN disk can accumulate, collide, scatter, and accrete. Intermediate mass black hole formation is likely in these disk locations, which may lead to preferential gap and cavity creation at these radii. Our model thus has significant implications for SMBH growth as well as gravitational wave source populations.

Monte Carlo Modeling the UCN τ Magneto-Gravitational Trap

Science.gov (United States)

Holley, A. T.; UCNτ Collaboration

2016-09-01

The current uncertainty in our knowledge of the free neutron lifetime is dominated by the nearly 4 σ discrepancy between complementary ``beam'' and ``bottle'' measurement techniques. An incomplete assessment of systematic effects is the most likely explanation for this difference and must be addressed in order to realize the potential of both approaches. The UCN τ collaboration has constructed a large-volume magneto-gravitational trap that eliminates the material interactions which complicated the interpretation of previous bottle experiments. This is accomplished using permanent NdFeB magnets in a bowl-shaped Halbach array to confine polarized UCN from the sides and below and the earth's gravitational field to trap them from above. New in situ detectors that count surviving UCN provide a means of empirically assessing residual systematic effects. The interpretation of that data, and its implication for experimental configurations with enhanced precision, can be bolstered by Monte Carlo models of the current experiment which provide the capability for stable tracking of trapped UCN and detailed modeling of their polarization. Work to develop such models and their comparison with data acquired during our first extensive set of systematics studies will be discussed.

Trapping, self-trapping and the polaron family

International Nuclear Information System (INIS)

Stoneham, A M; Gavartin, J; Shluger, A L; Kimmel, A V; Ramo, D Munoz; Roennow, H M; Aeppli, G; Renner, C

2007-01-01

The earliest ideas of the polaron recognized that the coupling of an electron to ionic vibrations would affect its apparent mass and could effectively immobilize the carrier (self-trapping). We discuss how these basic ideas have been generalized to recognize new materials and new phenomena. First, there is an interplay between self-trapping and trapping associated with defects or with fluctuations in an amorphous solid. In high dielectric constant oxides, like HfO 2 , this leads to oxygen vacancies having as many as five charge states. In colossal magnetoresistance manganites, this interplay makes possible the scanning tunnelling microscopy (STM) observation of polarons. Second, excitons can self-trap and, by doing so, localize energy in ways that can modify the material properties. Third, new materials introduce new features, with polaron-related ideas emerging for uranium dioxide, gate dielectric oxides, Jahn-Teller systems, semiconducting polymers and biological systems. The phonon modes that initiate self-trapping can be quite different from the longitudinal optic modes usually assumed to dominate. Fourth, there are new phenomena, like possible magnetism in simple oxides, or with the evolution of short-lived polarons, like muons or excitons. The central idea remains that of a particle whose properties are modified by polarizing or deforming its host solid, sometimes profoundly. However, some of the simpler standard assumptions can give a limited, indeed misleading, description of real systems, with qualitative inconsistencies. We discuss representative cases for which theory and experiment can be compared in detail

Stratigraphic dictionary of the mesozoic and cenozoic deposits of the western Siberian lowland. Stratigraficheskii slovar' mezozoiskikh i kainozoiskikh otlozhenii zapadno-Sibirskoi nizmennosti

Energy Technology Data Exchange (ETDEWEB)

Rostovtseva, N N

1978-01-01

The dictionary contains 655 descriptions of stratigraphic subdivisions (series, suites, subsuites, layers, packets, horizons, strata) of Triassic, Jurassic, Cretaceous, Tertiary, Neogene, and Quaternary deposits of the western Siberian lowland. Also presented are maps indicating the demarcation limits of all of the adopted stratigraphic subdivisions (Appendices 1 to 14), and correlative stratigraphic diagrams (Appendices 15 to 21). The dictionary may be of use as a reference manual for geologists of all fields of specialization, particularly for those working in western Siberia. 202 references, 21 figures.

Tectonic-stratigraphic evolution of Espirito Santo Basin - Brazil; Evolucao tectono-estratigrafica da Bacia do Espirito Santo

Energy Technology Data Exchange (ETDEWEB)

Silva, Eric Zagotto; Fernandes, Flavio L.; Lobato, Gustavo; Ferreira Neto, Walter Dias [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE). Lab. de Modelagem de Bacias (LAB2M); Petersohn, Eliane [Agencia Nacional do Petroleo, Gas Natural e Biocombustiveis (ANP), Brasilia, DF (Brazil)

2008-07-01

This paper documents the analysis of seismic data of the Espirito Santo basin obtained during the project realized through partnership between COPPE/UFRJ/Lab2M with the Agencia Nacional do Petroleo, Gas Natural e Biocombustiveis (ANP) during 2006 and 2007. The major objective of the seismic data interpretation in the project was to define the main structural and stratigraphic features in order to build a sedimentation model and a tectonic-stratigraphic evolution model of the Espirito Santo basin. Thus, the sedimentary package has been divided into eight genetic units (UN), grouped into five third order stratigraphic sequences, namely: UN-B, represented by siliciclastics rocks of the rift stage and evaporitic sag-rift stage, deposited during the Aptian; UN-C, which represents the carbonatic rocks deposited in a marine environment, and siliciclastics rocks located in the proximal portions during the Albian; and UN-D, represented by sediments, composed mainly by pelites, deposited in between the Cenomanian and Recent, and includes the Eocene volcanic event, which one changed the sedimentation pattern of the basin. (author)

Trapping radioactive ions

CERN Document Server

Kluge, Heinz-Jürgen

2004-01-01

Trapping devices for atomic and nuclear physics experiments with radioactive ions are becoming more and more important at accelerator facilities. While about ten years ago only one online Penning trap experiment existed, namely ISOLTRAP at ISOLDE/CERN, meanwhile almost every radioactive beam facility has installed or plans an ion trap setup. This article gives an overview on ion traps in the operation, construction or planing phase which will be used for fundamental studies with short-lived radioactive nuclides such as mass spectrometry, laser spectroscopy and nuclear decay spectroscopy. In addition, this article summarizes the use of gas cells and radiofrequency quadrupole (Paul) traps at different facilities as a versatile tool for ion beam manipulation like retardation, cooling, bunching, and cleaning.

Trapping radioactive ions

International Nuclear Information System (INIS)

Kluge, H.-J.; Blaum, K.

2004-01-01

Trapping devices for atomic and nuclear physics experiments with radioactive ions are becoming more and more important at accelerator facilities. While about ten years ago only one online Penning trap experiment existed, namely ISOLTRAP at ISOLDE/CERN, meanwhile almost every radioactive beam facility has installed or plans an ion trap setup. This article gives an overview on ion traps in the operation, construction or planing phase which will be used for fundamental studies with short-lived radioactive nuclides such as mass spectrometry, laser spectroscopy and nuclear decay spectroscopy. In addition, this article summarizes the use of gas cells and radiofrequency quadrupole (Paul) traps at different facilities as a versatile tool for ion beam manipulation like retardation, cooling, bunching, and cleaning

Effect of trap position on the efficiency of trapping in treelike scale-free networks

International Nuclear Information System (INIS)

Zhang Zhongzhi; Lin Yuan; Ma Youjun

2011-01-01

The conventional wisdom is that the role and impact of nodes on dynamical processes in scale-free networks are not homogenous, because of the presence of highly connected nodes at the tail of their power-law degree distribution. In this paper, we explore the influence of different nodes as traps on the trapping efficiency of the trapping problem taking place on scale-free networks. To this end, we study in detail the trapping problem in two families of deterministically growing scale-free networks with treelike structure: one family is non-fractal, the other is fractal. In the first part of this work, we attack a special case of random walks on the two network families with a perfect trap located at a hub, i.e. node with the highest degree. The second study addresses the case with trap distributed uniformly over all nodes in the networks. For these two cases, we compute analytically the mean trapping time (MTT), a quantitative indicator characterizing the trapping efficiency of the trapping process. We show that in the non-fractal scale-free networks the MTT for both cases follows different scalings with the network order (number of network nodes), implying that trap's position has a significant effect on the trapping efficiency. In contrast, it is presented that for both cases in the fractal scale-free networks, the two leading scalings exhibit the same dependence on the network order, suggesting that the location of trap has no essential impact on the trapping efficiency. We also show that for both cases of the trapping problem, the trapping efficiency is more efficient in the non-fractal scale-free networks than in their fractal counterparts.

Influence of trap location on the efficiency of trapping in dendrimers and regular hyperbranched polymers.

Science.gov (United States)

Lin, Yuan; Zhang, Zhongzhi

2013-03-07

The trapping process in polymer systems constitutes a fundamental mechanism for various other dynamical processes taking place in these systems. In this paper, we study the trapping problem in two representative polymer networks, Cayley trees and Vicsek fractals, which separately model dendrimers and regular hyperbranched polymers. Our goal is to explore the impact of trap location on the efficiency of trapping in these two important polymer systems, with the efficiency being measured by the average trapping time (ATT) that is the average of source-to-trap mean first-passage time over every staring point in the whole networks. For Cayley trees, we derive an exact analytic formula for the ATT to an arbitrary trap node, based on which we further obtain the explicit expression of ATT for the case that the trap is uniformly distributed. For Vicsek fractals, we provide the closed-form solution for ATT to a peripheral node farthest from the central node, as well as the numerical solutions for the case when the trap is placed on other nodes. Moreover, we derive the exact formula for the ATT corresponding to the trapping problem when the trap has a uniform distribution over all nodes. Our results show that the influence of trap location on the trapping efficiency is completely different for the two polymer networks. In Cayley trees, the leading scaling of ATT increases with the shortest distance between the trap and the central node, implying that trap's position has an essential impact on the trapping efficiency; while in Vicsek fractals, the effect of location of the trap is negligible, since the dominant behavior of ATT is identical, respective of the location where the trap is placed. We also present that for all cases of trapping problems being studied, the trapping process is more efficient in Cayley trees than in Vicsek fractals. We demonstrate that all differences related to trapping in the two polymer systems are rooted in their underlying topological structures.

Towards trapped antihydrogen

CERN Document Server

Jorgensen, L V; Bertsche, W; Boston, A; Bowe, P D; Cesar, C L; Chapman, S; Charlton, M; Fajans, J; Fujiwara, M C; Funakoshi, R; Gill, D R; Hangst, J S; Hayano, R S; Hydomako, R; Jenkins, M J; Kurchaninov, L; Madsen, N; Nolan, P; Olchanski, K; Olin, A; Page, R D; Povilus, A; Robicheaux, F; Sarid, E; Silveira, D M; Storey, J W; Thompson, R I; van der Werf, D P; Wurtele, J S; Yamazaki, Y

2008-01-01

Substantial progress has been made in the last few years in the nascent field of antihydrogen physics. The next big step forward is expected to be the trapping of the formed antihydrogen atoms using a magnetic multipole trap. ALPHA is a new international project that started to take data in 2006 at CERN’s Antiproton Decelerator facility. The primary goal of ALPHA is stable trapping of cold antihydrogen atoms to facilitate measurements of its properties. We discuss the status of the ALPHA project and the prospects for antihydrogen trapping.

Two-species mixing in a nested Penning trap for antihydrogen trapping

International Nuclear Information System (INIS)

Ordonez, C. A.; Weathers, D. L.

2008-01-01

There exists an international quest to trap neutral antimatter in the form of antihydrogen for scientific study. One method that is being developed for trapping antihydrogen employs a nested Penning trap. Such a trap serves to mix positrons and antiprotons so as to produce low energy antihydrogen atoms. Mixing is achieved when the confinement volumes of the two species overlap one another. In the work presented here, a theoretical understanding of the mixing process is developed by analyzing a mixing scheme that was recently reported [G. Gabrielse et al., Phys. Rev. Lett. 100, 113001 (2008)]. The results indicate that positron space charge or collisions among antiprotons may substantially reduce the fraction of antiprotons that have an energy suitable for antihydrogen trapping

Salt Repository Project site study plan for stratigraphic boreholes: Revision 1, December 18, 1987

International Nuclear Information System (INIS)

1987-01-01

This site study describes the Stratigraphic Boreholes field work to be conducted during the early stages of Site Characterization at the Deaf Smith County, Texas site. The field program has been designed to provide data useful in addressing information/data needs resulting from Federal/State/local regulations, and repository program requirements. Four Stratigraphic Holes will be drilled near the perimeter of the site to document the subsurface geologic conditions in that area and to provide data necessary for design and construction of the Exploratory Shaft Facilities. Continuous samples will be recovered from the ground surface to the total depth of each sell. Geophysical well logs will provide additional coverage of the stratigraphic section. In-situ down hole testing will include short term hydrologic tests and hydraulic fracture tests to provide information on deep groundwater characteristics and regional stress patterns, respectively. Field methods/tests are chosen that provide the best or only means of obtaining the required data. The Salt Repository Project (SRP) Networks specify the schedule which the program will operate. The Technical Services Contractor is responsible for conducting the field program of drilling and testing. Samples and data will be handled and reported in accordance with established SRP procedures. A quality assurance program will be utilized to assure that activities affecting quality are performed correctly and that the appropriate documentation is maintained. 30 refs., 13 figs., 4 tabs

The effects of deep trap population on the thermoluminescence of Al{sub 2}O{sub 3}:C

Energy Technology Data Exchange (ETDEWEB)

Yukihara, E.G. E-mail: yukihara@thor.phy.okstate.edu; Whitley, V.H.; Polf, J.C.; Klein, D.M.; McKeever, S.W.S.; Akselrod, A.E.; Akselrod, M.S

2003-12-01

The influence of deep traps on the 450 K thermoluminescence (TL) peak of Al{sub 2}O{sub 3}:C is studied. Depending upon the sample and on the degree of deep trap filling, features such as the TL width, area and height can vary considerably. These effects are interpreted to be due to: (a) sensitivity changes introduced by competition mechanisms involving deep electron and hole traps, and (b) the multiple component nature of the 450 K TL peak. The influence of the deep traps on the TL was studied using different excitation sources (beta irradiation or UV illumination), and step annealing procedures. Optical absorption measurements were used to monitor the concentration of F- and F{sup +}-centers. The data lead to the suggestion that the competing deep traps which become unstable at {approx}800-875 K are hole traps, and that the competing deep traps which become unstable at {approx}1100-1200 K are electron traps. Both the dose response of the TL signal and the TL sensitivity are shown to be influenced by sensitization and desensitization processes caused by the filling of deep electron and hole traps, respectively. Changes in the TL peak at low doses were also shown to be connected to the degree of filling of deep traps, emphasizing the influence of deep trap concentration and dose history of each sample in determining the TL properties of the material. Implications of these results for the optically stimulated luminescence properties are also discussed.

Dynamic analysis of trapping and escaping in dual beam optical trap

Science.gov (United States)

Li, Wenqiang; Hu, Huizhu; Su, Heming; Li, Zhenggang; Shen, Yu

2016-10-01

In this paper, we simulate the dynamic movement of a dielectric sphere in optical trap. This dynamic analysis can be used to calibrate optical forces, increase trapping efficiency and measure viscous coefficient of surrounding medium. Since an accurate dynamic analysis is based on a detailed force calculation, we calculate all forces a sphere receives. We get the forces of dual-beam gradient radiation pressure on a micron-sized dielectric sphere in the ray optics regime and utilize Einstein-Ornstein-Uhlenbeck to deal with its Brownian motion forces. Hydrodynamic viscous force also exists when the sphere moves in liquid. Forces from buoyance and gravity are also taken into consideration. Then we simulate trajectory of a sphere when it is subject to all these forces in a dual optical trap. From our dynamic analysis, the sphere can be trapped at an equilibrium point in static water, although it permanently fluctuates around the equilibrium point due to thermal effects. We go a step further to analyze the effects of misalignment of two optical traps. Trapping and escaping phenomena of the sphere in flowing water are also simulated. In flowing water, the sphere is dragged away from the equilibrium point. This dragging distance increases with the decrease of optical power, which results in escaping of the sphere with optical power below a threshold. In both trapping and escaping process we calculate the forces and position of the sphere. Finally, we analyze a trapping region in dual optical tweezers.

Accommodation and supply—a dual control on stratigraphic sequences

Science.gov (United States)

Schlager, Wolfgang

1993-07-01

It is widely accepted that both eustatic and tectonically controlled regional changes of sea level have contributed to the record of stratigraphic sequences. I suggest that environmental change be added as a third, autonomous control. Sedimentologic principles clearly indicate that sequences and their systems tracts are controlled by the interplay of two rates —the rate of change in accommodation (space available for sedimentation) and the rate of sediment supply. Sea level has direct control on accommodation, but its influence on sediment supply is remote and easily overshadowed by environmental factors. For instance, the record of the most recent sea-level rise is a transgressive systems tract where supply is low; it is a prograding highstand systems tract in deltas where the supply is high. Examples of sequence boundaries generated by changes in sediment supply include tectonically driven shifts in sediment input into basins, changes in ocean currents, pulsating supply from failure of submarine slopes and drowning of carbonate platforms by environmental stress. Furthermore, the stratigraphic sequences in fluviatile continental basins are physically removed from sea-level induced changes in accommodation and must have formed by changes in the rate and pattern of supply. Subaerial exposure of marine sediments at the sequence boundary is a most important criterion for recognizing sea level cycles as opposed to supply cycles. Other criteria include downstepping of shelf breaks and characteristic patterns in the spacing of time lines within sequences. Some third-order cycles (ca. 0.5-3 Ma duration) meet these criteria, others do not. Cycle-stacking patterns and the shifting facies belts on cratons indicate that many second- and third-order cycles lack pronounced exposure unconformities and represent gradual changes superimposed on more rapid, shorter oscillations. Seismic data yield poor images of these gradational changes because they lack resolution. Seismic

Are there Traps in Quantum Control Landscapes?

International Nuclear Information System (INIS)

Pechen, Alexander N.; Tannor, David J.

2011-01-01

There has been great interest in recent years in quantum control landscapes. Given an objective J that depends on a control field ε the dynamical landscape is defined by the properties of the Hessian δ 2 J/δε 2 at the critical points δJ/δε=0. We show that contrary to recent claims in the literature the dynamical control landscape can exhibit trapping behavior due to the existence of special critical points and illustrate this finding with an example of a 3-level Λ system. This observation can have profound implications for both theoretical and experimental quantum control studies.

Deuterium trapping in tungsten

Science.gov (United States)

Poon, Michael

Tungsten is one of the primary material candidates being investigated for use in the first-wall of a magnetic confinement fusion reactor. An ion accelerator was used to simulate the type of ion interaction that may occur at a plasma-facing material. Thermal desorption spectroscopy (TDS) was the primary tool used to analyze the effects of the irradiation. Secondary ion mass spectroscopy (SIMS) was used to determine the distribution of trapped D in the tungsten specimen. The tritium migration analysis program (TMAP) was used to simulate thermal desorption profiles from the D depth distributions. Fitting of the simulated thermal desorption profiles with the measured TDS results provided values of the D trap energies. Deuterium trapping in single crystal tungsten was studied as a function of the incident ion fluence, ion flux, irradiation temperature, irradiation history, and surface impurity levels during irradiation. The results show that deuterium was trapped at vacancies and voids. Two deuterium atoms could be trapped at a tungsten vacancy, with trapping energies of 1.4 eV and 1.2 eV for the first and second D atoms, respectively. In a tungsten void, D is trapped as atoms adsorbed on the inner walls of the void with a trap energy of 2.1 eV, or as D2 molecules inside the void with a trap energy of 1.2 eV. Deuterium trapping in polycrystalline tungsten was also studied as a function of the incident fluence, irradiation temperature, and irradiation history. Deuterium trapping in polycrystalline tungsten also occurs primarily at vacancies and voids with the same trap energies as in single crystal tungsten; however, the presence of grain boundaries promotes the formation of large surface blisters with high fluence irradiations at 500 K. In general, D trapping is greater in polycrystalline tungsten than in single crystal tungsten. To simulate mixed materials comprising of carbon (C) and tungsten, tungsten specimens were pre-irradiated with carbon ions prior to D

Deuterium trapping in tungsten

International Nuclear Information System (INIS)

Poon, M.

2004-01-01

Tungsten is one of the primary material candidates being investigated for use in the first-wall of a magnetic confinement fusion reactor. An ion accelerator was used to simulate the type of ion interaction that may occur at a plasma-facing material. Thermal desorption spectroscopy (TDS) was the primary tool used to analyze the effects of the irradiation Secondary ion mass spectroscopy (SIMS) was used to determine the distribution of trapped D in the tungsten specimen. The tritium migration analysis program (TMAP) was used to simulate thermal desorption profiles from the D depth distributions. Fitting of the simulated thermal desorption profiles with the measured TDS results provided values of the D trap energies. . Deuterium trapping in single crystal tungsten was studied as a function of the incident ion fluence, ion flux, irradiation temperature, irradiation history, and surface impurity levels during irradiation The results show that deuterium was trapped at vacancies and voids. Two deuterium atoms could be trapped at a tungsten vacancy, with trapping energies of 1.4 eV and 1.2 eV for the first and second D atoms, respectively. In a tungsten void, D is trapped as atoms adsorbed on the inner walls of the void with a trap energy of 2.1 eV, or as D 2 molecules inside the void with a trap energy of 1.2 eV. . Deuterium trapping in polycrystalline tungsten was also studied as a function of the incident fluence, irradiation temperature, and irradiation history. Deuterium trapping in polycrystalline tungsten also occurs primarily at vacancies and voids with the same trap energies as in single crystal tungsten; however, the presence of grain boundaries promotes the formation of large surface blisters with high fluence irradiations at 500 K. In general, D trapping is greater in polycrystalline tungsten than in single crystal tungsten. To simulate mixed materials comprising of carbon (C) and tungsten, tungsten specimens were pre-irradiated with carbon ions prior to D

Deuterium trapping in tungsten

Energy Technology Data Exchange (ETDEWEB)

Poon, M

2004-07-01

Tungsten is one of the primary material candidates being investigated for use in the first-wall of a magnetic confinement fusion reactor. An ion accelerator was used to simulate the type of ion interaction that may occur at a plasma-facing material. Thermal desorption spectroscopy (TDS) was the primary tool used to analyze the effects of the irradiation Secondary ion mass spectroscopy (SIMS) was used to determine the distribution of trapped D in the tungsten specimen. The tritium migration analysis program (TMAP) was used to simulate thermal desorption profiles from the D depth distributions. Fitting of the simulated thermal desorption profiles with the measured TDS results provided values of the D trap energies. . Deuterium trapping in single crystal tungsten was studied as a function of the incident ion fluence, ion flux, irradiation temperature, irradiation history, and surface impurity levels during irradiation The results show that deuterium was trapped at vacancies and voids. Two deuterium atoms could be trapped at a tungsten vacancy, with trapping energies of 1.4 eV and 1.2 eV for the first and second D atoms, respectively. In a tungsten void, D is trapped as atoms adsorbed on the inner walls of the void with a trap energy of 2.1 eV, or as D{sub 2} molecules inside the void with a trap energy of 1.2 eV. . Deuterium trapping in polycrystalline tungsten was also studied as a function of the incident fluence, irradiation temperature, and irradiation history. Deuterium trapping in polycrystalline tungsten also occurs primarily at vacancies and voids with the same trap energies as in single crystal tungsten; however, the presence of grain boundaries promotes the formation of large surface blisters with high fluence irradiations at 500 K. In general, D trapping is greater in polycrystalline tungsten than in single crystal tungsten. To simulate mixed materials comprising of carbon (C) and tungsten, tungsten specimens were pre-irradiated with carbon ions prior to D

Status and outlook of CHIP-TRAP: The Central Michigan University high precision Penning trap

Science.gov (United States)

Redshaw, M.; Bryce, R. A.; Hawks, P.; Gamage, N. D.; Hunt, C.; Kandegedara, R. M. E. B.; Ratnayake, I. S.; Sharp, L.

2016-06-01

At Central Michigan University we are developing a high-precision Penning trap mass spectrometer (CHIP-TRAP) that will focus on measurements with long-lived radioactive isotopes. CHIP-TRAP will consist of a pair of hyperbolic precision-measurement Penning traps, and a cylindrical capture/filter trap in a 12 T magnetic field. Ions will be produced by external ion sources, including a laser ablation source, and transported to the capture trap at low energies enabling ions of a given m / q ratio to be selected via their time-of-flight. In the capture trap, contaminant ions will be removed with a mass-selective rf dipole excitation and the ion of interest will be transported to the measurement traps. A phase-sensitive image charge detection technique will be used for simultaneous cyclotron frequency measurements on single ions in the two precision traps, resulting in a reduction in statistical uncertainty due to magnetic field fluctuations.

Evaluation method for acoustic trapping performance by tracking motion of trapped microparticle

Science.gov (United States)

Lim, Hae Gyun; Ham Kim, Hyung; Yoon, Changhan

2018-05-01

We report a method to evaluate the performances of a single-beam acoustic tweezer using a high-frequency ultrasound transducer. The motion of a microparticle trapped by a 45-MHz single-element transducer was captured and analyzed to deduce the magnitude of trapping force. In the proposed method, the motion of a trapped microparticle was analyzed from a series of microscopy images to compute trapping force; thus, no additional equipment such as microfluidics is required. The method could be used to estimate the effective trapping force in an acoustic tweezer experiment to assess cell membrane deformability by attaching a microbead to the surface of a cell and tracking the motion of the trapped bead, which is similar to a bead-based assay that uses optical tweezers. The results showed that the trapping force increased with increasing acoustic intensity and duty factor, but the force eventually reached a plateau at a higher acoustic intensity. They demonstrated that this method could be used as a simple tool to evaluate the performance and to optimize the operating conditions of acoustic tweezers.

Fluorescence profiles and cooling dynamics of laser-cooled Mg+ ions in a linear rf ion trap

International Nuclear Information System (INIS)

Zhao Xianzhen; Ryjkov, Vladimir L.; Schuessler, Hans A.

2006-01-01

Fluorescence line profiles and their implications on the cooling dynamics of the Mg + ions stored in a linear rf trap are studied. The line profile is dictated by the temperature of the ion cloud at different laser detunings. The upper bound of the lowest temperature was estimated for different values of the rf trapping potential amplitude and the buffer gas pressure. A general trend of this ultimate temperature to increase with the rf trapping voltage and buffer gas pressure is expected, with an abrupt change at some critical value corresponding to the transition to and from a strongly correlated liquid or crystal state. While on the one hand this expectation was confirmed when the buffer gas pressure was varied; on the other hand the influence of the amplitude of the trapping voltage on the ultimate temperature shows an interesting new feature of first dipping down before the sharp increase occurs

How do salt withdrawal minibasins form? Insights from forward modelling, and implications for hydrocarbon migration

Science.gov (United States)

Peel, Frank J.

2014-09-01

Existing models for the initiation of salt withdrawal minibasins focus on the role of triggers that exist within the minibasin, either stratigraphic (e.g. differential deposition) or tectonic (extension, translation or contraction). Existing studies tend to focus on complex settings, such as continental margins, which contain many different potential triggering mechanisms. It can be difficult in these settings to identify which process is responsible for minibasin initiation, or the influence of individual factors on their subsequent development. Salt withdrawal minibasins also exist in simpler settings, without any obvious intrinsic trigger; the region of the North German Basin used by Trusheim (1960) in the classic definition of salt withdrawal geometries was of this nature. There is no overall basal or surface slope, no major lateral movement, and there is no depositional heterogeneity. Previously recognized trigger processes for minibasin initiation do not apply in this benign setting, suggesting that other, potentially more fundamental, influences may be at work. A simple forward-modelling approach shows how, in the absence of any other mechanism, a new minibasin can develop as the consequence of salt movement driven by its neighbour, and families of withdrawal minibasins can propagate across a region from a single seed point. This new mechanism may explain how some minibasins appear to initiate before the sediment density has exceeded that of the underlying salt. The forward modelling also indicates that some minibasins begin to invert to form turtle anticlines before the underlying salt has been evacuated, so that the timing of turtle formation may not be diagnostic of weld formation. This mechanism may also give rise to salt-cored turtles that have a lens of salt trapped beneath their cores. These new findings have implications for hydrocarbon migration and trapping.

Calcium Atom Trap for Atom Trap Mass Spectrometer

Energy Technology Data Exchange (ETDEWEB)

Ko, Kwang Hoon; Park, Hyun Min; Han, Jae Min; Kim, Taek Soo; Cha, Yong Ho; Lim, Gwon; Jeong, Do Young [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2012-05-15

Trace isotope analysis has been an important role in science, archaeological dating, geology, biology and nuclear industry. Artificially produced fission products such as Sr-90, Cs-135 and Kr-85 can be released to the environment when nuclear accident occurs and the reprocessing factory operates. Thus, the analysis of them has been of interest in nuclear industry. But it is difficult to detect them due to low natural abundance less then 10-10. The ultra-trace radio isotopes have been analyzed by the radio-chemical method, accelerator mass spectrometer, and laser based method. The radiochemical method has been used in the nuclear industry. But this method has disadvantages of long measurement time for long lived radioisotopes and toxic chemical process for the purification. The accelerator mass spectrometer has high isotope selectivity, but the system is huge and it has the isobar effects. The laser based method, such as RIMS (Resonance Ionization Mass Spectrometry) is a basically isobar-effect free method. Recently, ATTA (Atom Trap Trace Analysis), one of the laser based method, has been successfully demonstrated sufficient isotope selectivity with small system size. It has been applied for the detection of Kr-81 and Kr-85. However, it is not suitable for real sample detection, because it requires steady atomic beam generation during detection and is not allowed simultaneous detection of other isotopes. Therefore, we proposed the coupled method of Atom Trap and Mass Spectrometer. It consists of three parts, neutral atom trap, ionization and mass spectrometer. In this paper, we present the demonstration of the magneto-optical trap of neutral calcium. We discuss the isotope selective characteristics of the MOT (Magneto Optical Trap) of calcium by the fluorescence measurement. In addition, the frequency stabilization of the trap beam will be presented

Heavy mineral delineation of the Cretaceous, Paleocene, and Eocene stratigraphic sections at the Savannah River Site, Upper Coastal Plain of South Carolina

International Nuclear Information System (INIS)

Cathcart, E.M.; Sargent, K.A.

1994-01-01

The Upper Atlantic Coastal Plain of South Carolina consists of a fluvial-deltaic and shallow marine complex of unconsolidated sediments overlying the crystalline basement rocks of the North American continent. Because of the lateral and vertical variability of these sediments, stratigraphic boundaries have been difficult to distinguish. Portions of the Cretaceous, Paleocene, and eocene stratigraphic sections from cores recovered during the construction of two monitoring wells at the Savannah River Site were studied to determine if heavy mineral suites could be utilized to distinguish boundaries. The stratigraphic sections include: the Late Cretaceous Middendorf, Black Creek, and Steel Creek Formations, the Paleocene Snapp Formation, the late Paleocene-Early Eocene Fourmile Branch Formation, and the Early Eocene Congaree formation. In previous studies composite samples were taken over 2.5 ft. intervals along the cores and processed using a heavy liquid for heavy mineral recovery. During this study, heavy mineral distributions were determined by binocular microscope and the mineral identifications confirmed by x-ray diffraction analysis of hand-picked samples. The heavy mineral concentration data and grain size data were then compared to the stratigraphic boundary positions determined by other workers using more classical methods. These comparisons were used to establish the utility of this method for delineating the stratigraphic boundaries in the area of study

Dual-mode optical fiber-based tweezers for robust trapping and manipulation of absorbing particles in air

Science.gov (United States)

Sil, Souvik; Kanti Saha, Tushar; Kumar, Avinash; Bera, Sudipta K.; Banerjee, Ayan

2017-12-01

We develop an optical tweezers system using a single dual-mode optical fiber where mesoscopic absorbing particles can be trapped in three dimensions and manipulated employing photophoretic forces. We generate a superposition of fundamental and first order Hermite-Gaussian beam modes by the simple innovation of coupling a laser into a commercial optical fiber designed to be single mode for a wavelength higher than that of the laser. We achieve robust trapping of the absorbing particles for hours using both the pure fundamental and superposition mode beams and attain large manipulation velocities of ˜5 mm s-1 in the axial direction and ˜0.75 mm s-1 in the radial direction. We then demonstrate that the superposition mode is more effective in trapping and manipulation compared to the fundamental mode by around 80%, which may be increased several times by the use of a pure first order Hermite-Gaussian mode. The work has promising implications for trapping and spectroscopy of aerosols in air using simple optical fiber-based traps.

Paleomagnetism of Siberian Trap Intrusions: Implications for the Timing and Intensity of the Magmatic Activity

Science.gov (United States)

Latyshev, Anton; Veselovskiy, Roman; Mirsayanova, Elina; Ulyahina, Polina

2016-04-01

Large Igneous Provinces (LIPs) are the areas of the exceptional interest due to associated Cu-Ni-Pt deposits, problems of the causal link between volcanic hazards and mass extinctions, and questions about mantle plume dynamics. High-precise U-Pb and 40Ar/39Ar dating determined the duration of the main phase of the most voluminous Siberian Trap province formation as 1-2 Ma (Kamo et al., 2003; Reichow et al., 2008). Recent paleomagnetic investigations demonstrated the predominance of pulsating volcanic activity during LIPs formation (Chenet et al., 2009; Pavlov et al., 2015). We perform the results of detailed paleomagnetic study of intrusive complexes from Tunguska syncline and Angara-Taseeva depression (Siberian Trap province). Our data taken together with the previous paleomagnetic results from trap intrusions revealed two different styles of magmatic activity. In the central part of Tunguska syncline emplacement of was rather even without sharp bursts. Local intrusive events coeval to volcanic eruptions took place within spatially limited areas. In contrast, in the periphery of Tunguska syncline several short and powerful peaks of magmatic activity happened on the background of weak prolonged magmatism. These events resulted in huge Padunsky, Tulunsky and some other sills in the southern part of the Siberian platform. According to our paleomagnetic data, the duration of such pulses did not exceed 10-100 thousand years. Taking into account our paleomagnetic data and recent U-Pb ages for Siberian trap intrusions from (Burgess, Bowring, 2015), it is possible to correlate intrusive complexes with the volcanic section. In particular, formation the largest Tulunsky and Padunsky sills happened right after the termination of the main phase of Permian-Triassic volcanic activity on the Siberian platform. This work was supported by grants RFBR # 16-35-60114 and 15-35-20599 and Ministry of Education and Science of the Russian Federation (grant 14.Z50.31.0017).

A live-trap and trapping technique for fossorial mammals

African Journals Online (AJOL)

mammals. G.C. Hickman. An effective live-trap was designed for Cryptomys hottentotus .... that there is an animal in the burrow system, and to lessen the likelihood of the .... the further testing and modification of existing trap types. Not only is it ...

Sequence stratigraphic interpretation of parts of Anambra Basin, Nigeria using geophysical well logs and biostratigraphic data

Science.gov (United States)

Anakwuba, E. K.; Ajaegwu, N. E.; Ejeke, C. F.; Onyekwelu, C. U.; Chinwuko, A. I.

2018-03-01

tract and highstand system tract found in Ajali, Nsukka, Nkporo and Imo (Ebenebe Sandstone) Formations show good continuity and as such good reservoir qualities while the shales of the transgressive system tracts which includes the Imo Formation, Mamu, and Nkporo Formations where most of the maximum flooding surfaces were delineated, can serve as seals to the numerous reservoir units. Combinations of the reservoir sands of the lowstand system tract and highstand system tract and the shale units of the transgressive system tract can form good stratigraphic traps for hydrocarbon and hence should be hydrocarbon exploration targets.

Case Study: Trap Crop with Pheromone Traps for Suppressing Euschistus servus (Heteroptera: Pentatomidae in Cotton

Directory of Open Access Journals (Sweden)

P. G. Tillman

2012-01-01

Full Text Available The brown stink bug, Euschistus servus (Say, can disperse from source habitats, including corn, Zea mays L., and peanut, Arachis hypogaea L., into cotton, Gossypium hirsutum L. Therefore, a 2-year on-farm experiment was conducted to determine the effectiveness of a sorghum (Sorghum bicolor (L. Moench spp. bicolor trap crop, with or without Euschistus spp. pheromone traps, to suppress dispersal of this pest to cotton. In 2004, density of E. servus was lower in cotton fields with sorghum trap crops (with or without pheromone traps compared to control cotton fields. Similarly, in 2006, density of E. servus was lower in cotton fields with sorghum trap crops and pheromone traps compared to control cotton fields. Thus, the combination of the sorghum trap crop and pheromone traps effectively suppressed dispersal of E. servus into cotton. Inclusion of pheromone traps with trap crops potentially offers additional benefits, including: (1 reducing the density of E. servus adults in a trap crop, especially females, to possibly decrease the local population over time and reduce the overwintering population, (2 reducing dispersal of E. servus adults from the trap crop into cotton, and (3 potentially attracting more dispersing E. servus adults into a trap crop during a period of time when preferred food is not prevalent in the landscape.

Angular trap for macroparticles

International Nuclear Information System (INIS)

Aksyonov, D.S.

2013-01-01

Properties of angular macroparticle traps were investigated in this work. These properties are required to design vacuum arc plasma filters. The correlation between trap geometry parameters and its ability to absorb macroparticles were found. Calculations allow one to predict the behaviour of filtering abilities of separators which contain such traps in their design. Recommendations regarding the use of angular traps in filters of different builds are given.

Trapped antihydrogen

Energy Technology Data Exchange (ETDEWEB)

Butler, E., E-mail: eoin.butler@cern.ch [CERN, Physics Department (Switzerland); Andresen, G. B. [Aarhus University, Department of Physics and Astronomy (Denmark); Ashkezari, M. D. [Simon Fraser University, Department of Physics (Canada); Baquero-Ruiz, M. [University of California, Department of Physics (United States); Bertsche, W. [Swansea University, Department of Physics (United Kingdom); Bowe, P. D. [Aarhus University, Department of Physics and Astronomy (Denmark); Cesar, C. L. [Universidade Federal do Rio de Janeiro, Instituto de Fisica (Brazil); Chapman, S. [University of California, Department of Physics (United States); Charlton, M.; Deller, A.; Eriksson, S. [Swansea University, Department of Physics (United Kingdom); Fajans, J. [University of California, Department of Physics (United States); Friesen, T.; Fujiwara, M. C. [University of Calgary, Department of Physics and Astronomy (Canada); Gill, D. R. [TRIUMF (Canada); Gutierrez, A. [University of British Columbia, Department of Physics and Astronomy (Canada); Hangst, J. S. [Aarhus University, Department of Physics and Astronomy (Denmark); Hardy, W. N. [University of British Columbia, Department of Physics and Astronomy (Canada); Hayden, M. E. [Simon Fraser University, Department of Physics (Canada); Humphries, A. J. [Swansea University, Department of Physics (United Kingdom); Collaboration: ALPHA Collaboration; and others

2012-12-15

Precision spectroscopic comparison of hydrogen and antihydrogen holds the promise of a sensitive test of the Charge-Parity-Time theorem and matter-antimatter equivalence. The clearest path towards realising this goal is to hold a sample of antihydrogen in an atomic trap for interrogation by electromagnetic radiation. Achieving this poses a huge experimental challenge, as state-of-the-art magnetic-minimum atom traps have well depths of only {approx}1 T ({approx}0.5 K for ground state antihydrogen atoms). The atoms annihilate on contact with matter and must be 'born' inside the magnetic trap with low kinetic energies. At the ALPHA experiment, antihydrogen atoms are produced from antiprotons and positrons stored in the form of non-neutral plasmas, where the typical electrostatic potential energy per particle is on the order of electronvolts, more than 10{sup 4} times the maximum trappable kinetic energy. In November 2010, ALPHA published the observation of 38 antiproton annihilations due to antihydrogen atoms that had been trapped for at least 172 ms and then released-the first instance of a purely antimatter atomic system confined for any length of time (Andresen et al., Nature 468:673, 2010). We present a description of the main components of the ALPHA traps and detectors that were key to realising this result. We discuss how the antihydrogen atoms were identified and how they were discriminated from the background processes. Since the results published in Andresen et al. (Nature 468:673, 2010), refinements in the antihydrogen production technique have allowed many more antihydrogen atoms to be trapped, and held for much longer times. We have identified antihydrogen atoms that have been trapped for at least 1,000 s in the apparatus (Andresen et al., Nature Physics 7:558, 2011). This is more than sufficient time to interrogate the atoms spectroscopically, as well as to ensure that they have relaxed to their ground state.

Optimization of multifunnel traps for emerald ash borer (Coleoptera: Buprestidae): influence of size, trap coating, and color.

Science.gov (United States)

Francese, Joseph A; Rietz, Michael L; Mastro, Victor C

2013-12-01

Field assays were conducted in southeastern and south-central Michigan in 2011 and 2012 to optimize green and purple multifunnel (Lindgren funnel) traps for use as a survey tool for the emerald ash borer, Agrilus planipennis Fairmaire. Larger sized (12- and 16-unit) multifunnel traps caught more beetles than their smaller-sized (4- and 8-unit) counterparts. Green traps coated with untinted (white) fluon caught almost four times as many adult A. planipennis as Rain-X and tinted (green) fluon-coated traps and almost 33 times more beetles than untreated control traps. Purple multifunnel traps generally caught much lower numbers of A. planipennis adults than green traps, and trap catch on them was not affected by differences in the type of coating applied. However, trap coating was necessary as untreated control purple traps caught significantly less beetles than traps treated with Rain-X and untinted or tinted (purple) fluon. Proportions of male beetles captured were generally much higher on green traps than on purple traps, but sex ratios were not affected by trap coating. In 2012, a new shade of purple plastic, based on a better color match to an attractive purple paint than the previously used purple, was used for trapping assays. When multifunnel traps were treated with fluon, green traps caught more A. planipennis adults than both shades of purple and a prism trap that was manufactured based on the same color match. Trap catch was not affected by diluting the fluon concentration applied to traps to 50% (1:1 mixture in water). At 10%, trap catch was significantly lowered.

Status of THe-Trap

Energy Technology Data Exchange (ETDEWEB)

Streubel, Sebastian; Eronen, Tommi; Hoecker, Martin; Ketter, Jochen; Blaum, Klaus [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Van Dyck, Robert S. Jr. [Department of Physics, University of Washington, Seattle, WA (United States)

2013-07-01

THe-Trap (short for Tritium-{sup 3}He Trap) is a Penning-trap setup dedicated to measure the {sup 3}H to {sup 3}He mass-ratio with a relative uncertainty of better than 10{sup -11}. The ratio is of relevance for the KArlsruhe TRItium Neutrino experiment (KATRIN), which aims to measure the electron anti-neutrino mass, by measuring the shape of the β-decay energy spectrum close to its endpoint. An independent measurement of the {sup 3}H to {sup 3}He mass-ratio pins down this endpoint, and thus will help to determine the systematics of KATRIN. The trap setup consists of two Penning-traps: One trap for precision measurements, the other trap for ion storage. Ideally, the trap content will be periodically switched, which reduces the time between the measurements of the two ions' motional frequencies. In 2012, a mass ratio measurement of {sup 12}C{sup 4+} to {sup 14}N{sup 5+} was performed to characterize systematic effects of the traps. This measurement yielded a accuracy of 10{sup -9}. Further investigations revealed that a major reason for the modest accuracy is the large axial amplitude of ∼100 μm, compared to a ideal case of 3 μm at 4 K. In addition, relative magnetic fluctuations at a 3 x 10{sup -10} level on a 10 h timescale need to be significantly improved. In this contribution, the aforementioned findings and further systematic studies will be presented.

Immunoregulation of Neutrophil Extracellular Trap Formation by Endothelial-Derived p33 (gC1q Receptor)

DEFF Research Database (Denmark)

Neumann, Ariane; Papareddy, Praveen; Westman, Johannes

2018-01-01

The formation of neutrophil extracellular traps (NETs) is a host defence mechanism, known to facilitate the entrapment and growth inhibition of many bacterial pathogens. It has been implicated that the translocation of myeloperoxidase (MPO) from neutrophilic granules to the nucleus is crucial to ...

Chemical Contaminants as Stratigraphic Markers for the Anthropocene

Science.gov (United States)

Kruge, M. A.

2012-12-01

Thousands and even millions of years from now, widespread anthropogenic contaminants in sediments would likely persist, incorporated into the geological record. They would inadvertently preserve evidence of our present era (informally designated as the Anthropocene Epoch) characterized by large human populations engaged in intensive industrial and agricultural activities. Hypothetical geologists in the distant future would likely find unusually high concentrations of a wide variety of contaminants at stratigraphic levels corresponding to our present time, analogous to the iridium anomaly marking the bolide impact event at the close of the Cretaceous Period. These would include both organic and inorganic substances, such as industrially-derived heavy metals (e.g., Hg, Pb, Cr, Zn) and hydrocarbons, both petrogenic (derived directly from petroleum) and pyrogenic (combustion products). While there are natural sources for these materials, such as volcanic eruptions, wildfires, and oil seeps, their co-occurrence would provide a signature characteristic of human activity. Diagnostic assemblages of organic compounds would carry an anthropogenic imprint. The distribution of polycyclic aromatic hydrocarbons (PAHs) in a sediment sample could distinguish between natural and human sources. Stable isotopic signatures would provide additional evidence. Concentrations of contaminants in the sedimentary record would increase exponentially with increasing proximity to urban source areas, where at present billions of people are collectively consuming vast quantities of fossil fuels and generating large amounts of waste. Aolian and marine transport prior to deposition has been seen at present to globally redistribute detectable amounts of contaminants including Hg and PAHs, even at great distances from principal source areas. For organic contaminants, deposition in an anoxic sedimentary environment could insure their preservation, increasing the likelihood of their inclusion in the

Optical trapping of gold aerosols

DEFF Research Database (Denmark)

Schmitt, Regina K.; Pedersen, Liselotte Jauffred; Taheri, S. M.

2015-01-01

Aerosol trapping has proven challenging and was only recently demonstrated.1 This was accomplished by utilizing an air chamber designed to have a minimum of turbulence and a laser beam with a minimum of aberration. Individual gold nano-particles with diameters between 80 nm and 200 nm were trapped...... in air using a 1064 nm laser. The positions visited by the trapped gold nano-particle were quantified using a quadrant photo diode placed in the back focal plane. The time traces were analyzed and the trapping stiffness characterizing gold aerosol trapping determined and compared to aerosol trapping...... of nanometer sized silica and polystyrene particles. Based on our analysis, we concluded that gold nano-particles trap more strongly in air than similarly sized polystyrene and silica particles. We found that, in a certain power range, the trapping strength of polystyrene particles is linearly decreasing...

Geologic, stratigraphic, thermal, and mechanical factors which influence repository design in the bedded salt environment

International Nuclear Information System (INIS)

Ashby, J.P.; Nair, O.; Ortman, D.; Rowe, J.

1979-12-01

This report describes the geologic, stratigraphic, thermal, and mechanical considerations applicable to repository design. The topics discussed in the report include: tectonic activity; geologic structure; stratigraphy; rock mechanical properties; and hydrologic properties

The Influence of Stratigraphic History on Landscape Evolution

Science.gov (United States)

Forte, A. M.; Yanites, B.; Whipple, K. X.

2016-12-01

Variation in rock erodibility can play a significant role in landscape evolution. Using a version of the CHILD landscape evolution model that allows for variations in rock erodibility, we found surprisingly complex landscape evolution in simulations with simple, two unit stratigraphies with contrasting erodibility. This work indicated that the stratigraphic order of units in terms of erodibility, the orientation of the contact with respect to the main drainage direction, and the contact dip angle all have pronounced effects on landscape evolution. Here we expand that work to explore the implications of more complicated stratigraphies on landscape evolution. Introducing multiple units adds additional controls on landscape evolution, namely the thicknesses and relative erodibility of rock layers. In models with a sequence of five alternating hard and soft units embedded within arbitrarily thick over- and underlying units, the number of individual layers that noticeably influence landscape morphology decreases as the thickness of individual layers reduces. Contacts with soft rocks over hard produce the most noticeable effect in model output such as erosion rate and channel steepness. For large contrasts in erodibility of 25 m thick layers, only one soft over hard contact is clearly manifest in the landscape. Between 50 and 75 m, two such contacts are manifest, and by 100 m thickness, all three of these contacts are manifest. However, for a given thickness of layers, more units are manifest in the landscape as the erodibility contrast between units decreases. This is true even though the magnitude of landscape effects away from steady-state erosion rates or channel steepness also decrease with decreasing erodibility contrast. Finally, we explore suites of models with alternating layers reflecting either `hardening-' or `softening-upwards' stratigraphies and find that the two scenarios result in decidedly different landscape forms. Hardening-upwards sections produce a

Drilling rate for the Cerro Prieto stratigraphic sequence

Energy Technology Data Exchange (ETDEWEB)

Prian C, R.

1981-01-01

Drilling practice at the field has been modified in several ways as better information is being obtained. The stratigraphic sequence of the area is made up of three sedimentary rock units of deltaic origin having different densities. These units have been named non-consolidated, semi-consolidated, and consolidated rocks; the thermal reservoirs are located in the latter. To investigate how the drilling rates are affected by the three rock units, plots of drilling advance versus time were made for a large number of wells. A typical plot is shown and drilling rates are practically constant in three different zones; that is, the drilling rate has only two breaks or changes in slope.

Geochemical evaluation of a shale stratigraphic profile from Paraiba Valley (Tremembe)

International Nuclear Information System (INIS)

Loureiro, M.R.B.; Cardoso, J.N.

1987-01-01

The sedimentary core ranges 0-35m depth and covers three types of bituminous shales, intercalated by two layers of sterile clay. A systematic geochemical study of samples of most stratigraphic layers was undertaken for the first time in this work, including elemental analysis (C, H), carbonate content, type of organic matter, infrared spectrometry and molecular characterization of organic extracts (hight-resolution) gas chromatography, mass spectrometry). No consistent correlation between lithology and amount/type of organic matter was observed, contrary to literature data, pointing out the paper shale strata as richest in organic matter. Molecular stratigraphy of the core presented similar n-alkane profiles generally maximizing at n-C 27 attesting to a small variation in input along the sedimentary section. Characterization of the branched/cyclic hydrocarbons evidenced a continental input to the sediment, as revealed by the presence, in several layers, of isometric des-A-fernenes, presumed products of diagenesis of arborinone. A microbial input was also evidenced through the general occurrence of hopanoids, trace amounts of steroidal skeletons as well as atomic H/C ratios ca. 2. The sharp variations in biomarker profiles with depth showed great potential as correlation markers in a detailed stratigraphic study of the basin, as a valuable supplement to traditional lithological parameters. (author) [pt

Search For Trapped Antihydrogen

CERN Document Server

Andresen, Gorm B.; Baquero-Ruiz, Marcelo; Bertsche, William; Bowe, Paul D.; Bray, Crystal C.; Butler, Eoin; Cesar, Claudio L.; Chapman, Steven; Charlton, Michael; Fajans, Joel; Friesen, Tim; Fujiwara, Makoto C.; Gill, David R.; Hangst, Jeffrey S.; Hardy, Walter N.; Hayano, Ryugo S.; Hayden, Michael E.; Humphries, Andrew J.; Hydomako, Richard; Jonsell, Svante; Jorgensen, Lars V.; Kurchaninov, Lenoid; Lambo, Ricardo; Madsen, Niels; Menary, Scott; Nolan, Paul; Olchanski, Konstantin; Olin, Art; Povilus, Alexander; Pusa, Petteri; Robicheaux, Francis; Sarid, Eli; Nasr, Sarah Seif El; Silveira, Daniel M.; So, Chukman; Storey, James W.; Thompson, Robert I.; van der Werf, Dirk P.; Wilding, Dean; Wurtele, Jonathan S.; Yamazaki, Yasunori

2011-01-01

We present the results of an experiment to search for trapped antihydrogen atoms with the ALPHA antihydrogen trap at the CERN Antiproton Decelerator. Sensitive diagnostics of the temperatures, sizes, and densities of the trapped antiproton and positron plasmas have been developed, which in turn permitted development of techniques to precisely and reproducibly control the initial experimental parameters. The use of a position-sensitive annihilation vertex detector, together with the capability of controllably quenching the superconducting magnetic minimum trap, enabled us to carry out a high-sensitivity and low-background search for trapped synthesised antihydrogen atoms. We aim to identify the annihilations of antihydrogen atoms held for at least 130 ms in the trap before being released over ~30 ms. After a three-week experimental run in 2009 involving mixing of 10^7 antiprotons with 1.3 10^9 positrons to produce 6 10^5 antihydrogen atoms, we have identified six antiproton annihilation events that are consist...

Stratigraphic cross section of measured sections and drill holes of the Neslan Formation and adjacent formations, Book Cliffs Area, Colorado and Utah

Science.gov (United States)

Kirshbaum, Mark A.; Spear, Brianne D.

2012-01-01

This study updates a stratigraphic cross section published as plate 2 in Kirschbaum and Hettinger (2004) Digital Data Series 69-G (http://pubs.usgs.gov/dds/dds-069/dds-069-g/). The datum is a marine/tidal ravinement surface within the Cozzette Sandstone Member of the Iles Formation and the Thompson Canyon Sandstone and Sulphur Canyon Sandstone Beds of the Neslen Formation. One of the cores shown was included on the original cross section, and new core descriptions have been added to the upper part of the cored interval. A new core description (S178) is included in this report. Cores are stored in the U.S. Geological Survey Core Research Facility at the Denver Federal Center, Colorado. The following information has also been added to help define the stratigraphic framework: 1) At least five claystones interpreted as altered volcanic ashes have been identified and may give future workers a correlation tool within the largely continental section. 2) Thickness and general geometry of the Sego Sandstone, Buck Tongue of the Mancos Shale, and Castlegate Sandstone have been added to provide additional stratigraphic context. 3) The geometry in the Sego Sandstone, Buck Tongue of the Mancos Shale, and Castlegate Sandstone has been added to provide additional stratigraphic context. 4) Ammonite collections are from Gill and Hail. The zone of Didymoceras nebrascense projected into the East Salt Wash area is based on correlation of the flooding surface at the base of the Cozzette Member to this point as shown in Kirschbaum and Hettinger. 5) A leaf locality of the Denver Museum of Nature and Science is shown in its approximate stratigraphic position near Thompson Canyon. 6) A dinosaur locality of the Natural History Museum of Utah is shown in the Horse Canyon area measured section at the stratigraphic position where it was extracted.

Injection into electron plasma traps

International Nuclear Information System (INIS)

Gorgadze, Vladimir; Pasquini, Thomas A.; Fajans, Joel; Wurtele, Jonathan S.

2003-01-01

Computational studies and experimental measurements of plasma injection into a Malmberg-Penning trap reveal that the number of trapped particles can be an order of magnitude higher than predicted by a simple estimates based on a ballistic trapping model. Enhanced trapping is associated with a rich nonlinear dynamics generated by the space-charge forces of the evolving trapped electron density. A particle-in-cell simulation is used to identify the physical mechanisms that lead to the increase in trapped electrons. The simulations initially show strong two-stream interactions between the electrons emitted from the cathode and those reflected off the end plug of the trap. This is followed by virtual cathode oscillations near the injection region. As electrons are trapped, the initially hollow longitudinal phase-space is filled, and the transverse radial density profile evolves so that the plasma potential matches that of the cathode. Simple theoretical arguments are given that describe the different dynamical regimes. Good agreement is found between simulation and theory

[Trapping techniques for Solenopsis invicta].

Science.gov (United States)

Liang, Xiao-song; Zhang, Qiang; Zhuang, Yiong-lin; Li, Gui-wen; Ji, Lin-peng; Wang, Jian-guo; Dai, Hua-guo

2007-06-01

A field study was made to investigate the trapping effects of different attractants, traps, and wind directions on Solenopsis invicta. The results showed that among the test attractants, TB1 (50 g fishmeal, 40 g peptone, 10 ml 10% sucrose water solution and 20 ml soybean oil) had the best effect, followed by TB2 (ham), TB6 (100 g cornmeal and 20 ml soybean oil) and TB4 (10 ml 10% sucrose water solution, 100 g sugarcane powder and 20 ml soybean oil), with a mean capture efficiency being 77.6, 58.7, 29 and 7.7 individuals per trap, respectively. No S. invicta was trapped with TB3 (10 ml 10% sucrose water solution, 100 g cornmeal and 20 ml soybean oil) and TB5 (honey). Tube trap was superior to dish trap, with a trapping efficiency of 75.2 and 35 individuals per trap, respectively. The attractants had better effects in leeward than in windward.

Microsatellite marker analysis of peach-potato aphids (Myzus persicae, Homoptera: Aphididae) from Scottish suction traps.

Science.gov (United States)

Malloch, G; Highet, F; Kasprowicz, L; Pickup, J; Neilson, R; Fenton, B

2006-12-01

The peach-potato aphid Myzus persicae (Sulzer) is an important vector of plant viruses. A network of suction traps collects aerial samples of this aphid in order to monitor and help predict its spatial distribution and likely impact on virus transmission in crops. A suction trap catch is thought to be a good representation of the total aphid pool. Sensitive molecular markers have been developed that determine the genetic composition of the M. persicae population. In Scotland, UK, these were applied to field collections revealing a limited number of clones. Molecular markers are less successful when applied to specimens that have been preserved in an ethanol-based trap fluid designed to preserve morphology. An assessment of different DNA extraction and PCR techniques is presented and the most efficient are used to analyse M. persicae specimens caught in the Dundee suction trap in 2001, a year when exceptionally high numbers were caught. The results reveal that the majority of the M. persicae caught belonged to two highly insecticide resistant clones. In addition, it was possible to compare the relative frequencies of genotypes caught in the trap with those collected at insecticide treated and untreated field sites in the vicinity. These results indicate that, in addition to suction trap data, the ability to sample field sites provides valuable early warning data which have implications for pest control and virus management strategies.

Separation of effects of oxide-trapped charge and interface-trapped charge on mobility in irradiated power MOSFETs

International Nuclear Information System (INIS)

Zupac, D.; Galloway, K.F.; Khosropour, P.; Anderson, S.R.; Schrimpf, R.D.

1993-01-01

An effective approach to separating the effects of oxide-trapped charge and interface-trapped charge on mobility degradation in irradiated MOSFETs is demonstrated. It is based on analyzing mobility data sets which have different functional relationships between the radiation-induced-oxide-trapped charge and interface-trapped charge. Separation of effects of oxide-trapped charge and interface-trapped charge is possible only if these two trapped charge components are not linearly dependent. A significant contribution of oxide-trapped charge to mobility degradation is demonstrated and quantified

Selected stratigraphic data for drill holes located in Frenchman Flat, Nevada Test Site. Rev. 1

International Nuclear Information System (INIS)

Drellack, S.L. Jr.

1997-02-01

Stratigraphic data are presented in tabular form for 72 holes drilled in Frenchman Flat, Nevada Test Site, between 1950 and 1993. Three pairs of data presentations are included for each hole: depth to formation tops, formation thicknesses, and formation elevations are presented in both field (English) and metric units. Also included for each hole, where available, are various construction data (hole depth, hole diameter, surface location coordinates) and certain information of hydrogeologic significance (depth to water level, top of zeolitization). The event name is given for holes associated with a particular nuclear test. An extensive set of footnotes is included, which indicates data sources and provides other information. The body of the report describes the stratigraphic setting of Frenchman Flat, gives drill-hole naming conventions and database terminology, and provides other background and reference material

Electron traps in semiconducting polymers : Exponential versus Gaussian trap distribution

NARCIS (Netherlands)

Nicolai, H. T.; Mandoc, M. M.; Blom, P. W. M.

2011-01-01

The low electron currents in poly(dialkoxy-p-phenylene vinylene) (PPV) derivatives and their steep voltage dependence are generally explained by trap-limited conduction in the presence of an exponential trap distribution. Here we demonstrate that the electron transport of several PPV derivatives can

Electron traps in semiconducting polymers: exponential versus Gaussian trap distribution

NARCIS (Netherlands)

Nicolai, H.T.; Mandoc, M.M.; Blom, P.W.M.

2011-01-01

The low electron currents in poly(dialkoxy-p-phenylene vinylene) (PPV) derivatives and their steep voltage dependence are generally explained by trap-limited conduction in the presence of an exponential trap distribution. Here we demonstrate that the electron transport of several PPV derivatives can

The Formation of Charon's Red Poles from Seasonally Cold-Trapped Volatiles

Science.gov (United States)

Grundy, W. M.; Cruikshank, D. P.; Gladstone, D. R.; Howett, C. J. A.; Lauer, T. R.; Spencer, J. R.; Summers, M. E.; Buie, M. W.; Earle, A. M.; Ennico, K.;

OWL representation of the geologic timescale implementing stratigraphic best practice

Science.gov (United States)

Cox, S. J.

2011-12-01

The geologic timescale is a cornerstone of the earth sciences. Versions are available from many sources, with the following being of particular interest: (i) The official International Stratigraphic Chart (ISC) is maintained by the International Commission for Stratigraphy (ICS), following principles developed over the last 40 years. ICS provides the data underlying the chart as part of a specialized software package, and the chart itself as a PDF using the standard colours; (ii) ITC Enschede has developed a representation of the timescale as a thesaurus in SKOS, used in a Web Map Service delivery system; (iii) JPL's SWEET ontology includes a geologic timescale. This takes full advantage of the capabilities of OWL. However, each of these has limitations - The ISC falls down because of incompatibility with web technologies; - While SKOS supports multilingual labelling, SKOS does not adequately support timescale semantics, in particular since it does not include ordering relationships; - The SWEET version (as of version 2) is not fully aligned to the model used by ICS, in particular not recognizing the role of the Global Boundary Stratotype Sections and Point (GSSP). Furthermore, it is distributed as static documents, rather than through a dynamic API using SPARQL. The representation presented in this paper overcomes all of these limitations as follows: - the timescale model is formulated as an OWL ontology - the ontology is directly derived from the UML representation of the ICS best practice proposed by Cox & Richard [2005], and subsequently included as the Geologic Timescale package in GeoSciML (http://www.geosciml.org); this includes links to GSSPs as per the ICS process - key properties in the ontology are also asserted to be subProperties of SKOS properties (topConcept and broader/narrower relations) in order to support SKOS-based queries; SKOS labelling is used to support multi-lingual naming and synonyms - the International Stratigraphic Chart is implemented

Secretion Trap Tagging of Secreted and Membrane-Spanning Proteins Using Arabidopsis Gene Traps

Science.gov (United States)

Andrew T. Groover; Joseph R. Fontana; Juana M. Arroyo; Cristina Yordan; W. Richard McCombie; Robert A. Martienssen

2003-01-01

Secreted and membrane-spanning proteins play fundamental roles in plant development but pose challenges for genetic identification and characterization. We describe a "secretion trap" screen for gene trap insertions in genes encoding proteins routed through the secretory pathway. The gene trap transposon encodes a ß-glucuronidase reporter enzyme...

Inversion aided systems for stratigraphic models; Systemes d'aide a l'inversion des modeles stratigraphiques

Energy Technology Data Exchange (ETDEWEB)

Dobranszky, G.

2005-12-15

Stratigraphic modeling aims at rebuilding the history of the sedimentary basins by simulating the processes of erosion, transport and deposit of sediments using physical models. The objective is to determine the location of the bed-rocks likely to contain the organic matter, the location of the porous rocks that could trap the hydrocarbons during their migration and the location of the impermeable rocks likely to seal the reservoir. The model considered within this thesis is based on a multi-lithological diffusive transport model and applies to large scales of time and space. Due to the complexity of the phenomena and scales considered, none of the model parameters is directly measurable. Therefore it is essential to inverse them. The standard approach, which consists in inverting all the parameters by minimizing a cost function using a gradient method, proved very sensitive to the choice of the parameterization, to the weights given to the various terms of the cost function (hearing on data of very diverse nature) and to the numerical noise. These observations led us to give up this method and to carry out the in-version step by step by decoupling the parameters. This decoupling is not obtained by fixing the parameters but by making several assumptions on the model resulting in a range of reduced but relevant models. In this thesis, we show how these models enable us to inverse all the parameters in a robust and interactive way. (author)

SEDIMENTATION AND BASIN-FILL HISTORY OF THE PLIOCENE SUCCESSION EXPOSED IN THE NORTHERN SIENA-RADICOFANI BASIN (TUSCANY, ITALY: A SEQUENCE-STRATIGRAPHIC APPROACH

Directory of Open Access Journals (Sweden)

IVAN MARTINI

2017-08-01

Full Text Available Basin-margin paralic deposits are sensitive indicators of relative sea-level changes and typically show complex stratigraphic architectures that only a facies-based sequence-stratigraphic approach, supported by detailed biostratigraphic data, can help unravel, thus providing constraints for the tectono-stratigraphic reconstructions of ancient basins. This paper presents a detailed facies analysis of Pliocene strata exposed in a marginal key-area of the northern Siena-Radicofani Basin (Tuscany, Italy, which is used as a ground for a new sequence-stratigraphic scheme of the studied area. The study reveals a more complex sedimentary history than that inferred from the recent geological maps produced as part of the Regional Cartographic Project (CARG, which are based on lithostratigraphic principles. Specifically, four sequences (S1 to S4, in upward stratigraphic order have been recognised, each bounded by erosional unconformities and deposited within the Zanclean-early Gelasian time span. Each sequence typically comprises fluvial to open marine facies, with deposits of different sequences that show striking lithological similarities.The architecture and internal variability shown by the studied depositional sequences are typical of low-accommodation basin-margin settings, that shows: i a poorly-developed to missing record of the falling-stage systems tract; ii a lowstand system tract predominantly made of fluvio-deltaic deposits; iii a highstand system tract with substantial thickness variation between different sequences due to erosional processes associated with the overlying unconformity; iv a highly variable transgressive system tract, ranging from elementary to parasequential organization.

Trapping for invasive crayfish: comparisons of efficacy and selectivity of baited traps versus novel artificial refuge traps

Directory of Open Access Journals (Sweden)

Green Nicky

2018-01-01

Full Text Available Non-native crayfish can dominate the invertebrate biomass of invaded freshwaters, with their high ecological impacts resulting in their populations being controlled by numerous methods, especially trapping. Although baited funnel traps (BTs are commonly used, they tend to be selective in mainly catching large-bodied males. Here, the efficacy and selectivity of BTs were tested against an alternative trapping method based on artificial refuges (ARTs that comprised of a metal base with several tubes (refuges attached. The target species was signal crayfish Pacifastacus leniusculus in an upland river in southwest England. Trapping was completed in April to October over two consecutive years. In total, 5897 crayfish were captured, with 87% captured in ARTs. Comparison of the catch per unit effort (CPUE between the trapping methods in the same 24 hour periods revealed significantly higher CPUE in ARTs than of BTs. ARTs fished for 6 consecutive days had higher catches than both methods over 24 hours. Whilst catches in BTs were significantly dominated by males (1.49M:1F, the sex ratio of catches in ARTs was 0.99M:1F. The mean carapace length of crayfish was also significantly larger in BTs (43.2 ± 0.6 mm than in ARTs (33.6 ± 0.2 mm. Thus, ARTs had higher CPUE over 24 hour and 6 day periods versus BTs and also captured a greater proportion of smaller and female individuals. These results indicate that when trapping methods are deployed for managing invasions, the use of ARTs removes substantial numbers of crayfish of both sexes and of varying body sizes.

Electromagnetic trapping of neutral atoms

International Nuclear Information System (INIS)

Metcalf, H.J.

1986-01-01

Cooling and trapping of neutral atoms is a new branch of applied physics that has potential for application in many areas. The authors present an introduction to laser cooling and magnetic trapping. Some basic ideas and fundamental limitations are discussed, and the first successful experiments are reviewed. Trapping a neutral object depends on the interaction between an inhomogeneous electromagnetic field and a multiple moment that results in the exchange of kinetic for potential energy. In neutral atom traps, the potential energy must be stored as internal atomic energy, resulting in two immediate and extremely important consequences. First, the atomic energy levels will necessarily shift as the atoms move in the trap, and, second, practical traps for ground state neutral atoms atr necessarily very shallow compared to thermal energy. This small depth also dictates stringent vacuum requirements because a trapped atom cannot survive a single collision with a thermal energy background gas molecule. Neutral trapping, therefore, depends on substantial cooling of a thermal atomic sample and is inextricably connected with the cooling process

Does Trapping Influence Decision-Making under Ambiguity in White-Lipped Peccary (Tayassu pecari?

Directory of Open Access Journals (Sweden)

Selene Siqueira da Cunha Nogueira

Full Text Available The white-lipped peccary (Tayassu pecari is an endangered species whose bold anti-predator behaviour in comparison to related species may increase its vulnerability to hunting and predation. We used a judgement bias test to investigate whether captive peccaries that had recently experienced a trapping event made more 'pessimistic' decisions under ambiguity. If so, this would indicate (i that the procedure may induce a negative affective state and hence have welfare implications, and (ii that the species is able to adopt a cautious response style despite its bold phenotype. Eight individuals were trained to 'go' to a baited food bowl when a positive auditory cue (whistle; CS+ was given and to 'no-go' when a negative cue (horn A; CS- was sounded to avoid a loud sound and empty food bowl. An 'ambiguous' auditory cue (bell; CSA was presented to probe decision-making under ambiguity. Individuals were subjected to three tests in the order: T1 (control-no trap, T2 (24h after-trap procedure, and T3 (control-no trap. In each test, each animal was exposed to 10 judgement bias trials of each of the three cue types: CS+,CS-,CSA. We recorded whether animals reached the food bowl within 60s ('go' response and their response speed (m/s. The animals varied in their responses to the CSA cue depending on test type. In all tests, animals made more 'go' responses to CS+ than CSA. During control tests (T1 and T3, the peccaries showed higher proportions of 'go' responses to CSA than to CS-. In T2, however, the animals showed similar proportions of 'go' responses to CSA and CS-, treating the ambiguous cue similarly to the negative cue. There were differences in their response speed according to cue type: peccaries were faster to respond to CS+ than to CS- and CSA. Trapping thus appeared to cause a 'pessimistic' judgement bias in peccaries, which may reflect a negative affective state with implications for the welfare and management of captive individuals, and also

The β-decay Paul trap: A radiofrequency-quadrupole ion trap for precision β-decay studies

International Nuclear Information System (INIS)

Scielzo, N.D.; Li, G.; Sternberg, M.G.; Savard, G.; Bertone, P.F.; Buchinger, F.; Caldwell, S.; Clark, J.A.; Crawford, J.; Deibel, C.M.; Fallis, J.; Greene, J.P.

2012-01-01

The β-decay Paul trap is a linear radiofrequency-quadrupole ion trap that has been developed for precision β-decay studies. The design of the trap electrodes allows a variety of radiation detectors to surround the cloud of trapped ions. The momentum of the low-energy recoiling daughter nuclei following β decay is negligibly perturbed by scattering and is available for study. This advantageous property of traps allows the kinematics of particles that are difficult or even impossible to directly detect to be precisely reconstructed using conservation of energy and momentum. An ion-trap system offers several advantages over atom traps, such as higher trapping efficiencies and element-independent capabilities. The first precision experiment using this system is a measurement of β-decay angular correlations in the decay of 8 Li performed by inferring the momentum of the neutrino from the kinematic shifts imparted to the breakup α particles. Many other β-decay studies that would benefit from a determination of the nuclear recoil can be performed with this system.

The {beta}-decay Paul trap: A radiofrequency-quadrupole ion trap for precision {beta}-decay studies

Energy Technology Data Exchange (ETDEWEB)

Scielzo, N.D., E-mail: scielzo1@llnl.gov [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Li, G. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Department of Physics, McGill University, Montreal, Quebec, Canada H3A 2T8 (Canada); Sternberg, M.G.; Savard, G. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Department of Physics, University of Chicago, Chicago, Illinois 60637 (United States); Bertone, P.F. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Buchinger, F. [Department of Physics, McGill University, Montreal, Quebec, Canada H3A 2T8 (Canada); Caldwell, S. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Department of Physics, University of Chicago, Chicago, Illinois 60637 (United States); Clark, J.A. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Crawford, J. [Department of Physics, McGill University, Montreal, Quebec, Canada H3A 2T8 (Canada); Deibel, C.M. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Joint Institute for Nuclear Astrophysics, Michigan State University, East Lansing, Michigan 48824 (United States); Fallis, J. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2 (Canada); Greene, J.P. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); and others

2012-07-21

The {beta}-decay Paul trap is a linear radiofrequency-quadrupole ion trap that has been developed for precision {beta}-decay studies. The design of the trap electrodes allows a variety of radiation detectors to surround the cloud of trapped ions. The momentum of the low-energy recoiling daughter nuclei following {beta} decay is negligibly perturbed by scattering and is available for study. This advantageous property of traps allows the kinematics of particles that are difficult or even impossible to directly detect to be precisely reconstructed using conservation of energy and momentum. An ion-trap system offers several advantages over atom traps, such as higher trapping efficiencies and element-independent capabilities. The first precision experiment using this system is a measurement of {beta}-decay angular correlations in the decay of {sup 8}Li performed by inferring the momentum of the neutrino from the kinematic shifts imparted to the breakup {alpha} particles. Many other {beta}-decay studies that would benefit from a determination of the nuclear recoil can be performed with this system.

Theory of modulational interaction of trapped ion convective cells and drift wave turbulence

International Nuclear Information System (INIS)

Shapiro, V.D.; Diamond, P.H.; Lebedev, V.; Soloviev, G.; Shevchenko, V.

1993-01-01

Theoretical and computational studies of the modulational interaction between trapped ion convective cells and short wavelength drift wave turbulence are discussed. These studies are motivated by the fact that cells and drift waves are expected to coexist in tokamaks so that: (a) cells strain and modulate drift waves, and (b) drift waves open-quote ride on close-quote a background of cells. The results of the authors' investigation indicate that: (1) (nonlinear) parametric growth rates of trapped ion convective cells can exceed linear predictions (for drift wave levels at the mixing length limit); (2) a set of coupled envelope equations, akin to the Zakharov equations from Langmuir turbulence, can be derived and used to predict the formation of a dipole pair of convective cells trapped by the drift wave envelope. This dipole pair is strongly anisotropic, due to the structure of the drift wave Reynolds stress which drives the cell flow. Numerical solutions of the envelope equations are in good agreement with theoretical predictions, and indicate the persistence of the structure in time; (3) strong modulation and trapping of drift waves with k perpendicular ρ > 1 occurs. Extensions to magnetically sheared systems and the broader implications of this work as a paradigm for the dynamics of persistent structures in shearing flows are discussed

Genetic and stratigraphic significance of the Upper Devonian Frasnian Z Marker, west-central Alberta

Energy Technology Data Exchange (ETDEWEB)

Wendte, J. [Geological Survey of Canada, Calgary, AB (Canada); Stoakes, F. [Stoakes Consulting Group Ltd., Calgary, AB (Canada); Bosman, M. [Canadian Hunter Exploration Ltd., Calgary, AB (Canada); Bernstein, L. [Talisman Energy Inc., Calgary, AB (Canada)

1995-12-01

The stratigraphic model from the west-central Alberta basin was provided. It defined the Z Marker as a distinctive and widespread wireline log marker within the thick Frasnian Ireton shale basin succession. The marker represents an interval of condensed sedimentation and corresponds to an abrupt change from a calcareous signature below to an argillaceous character above. Toward the shelf, in the West Pembina area, the Z Marker correlates to a level within a conformable succession of nodular lime wackestones and corresponds to the base of a depositional cycle near the middle of the Lobstick member of the Nisku Formation. Further shelfward, the Z Marker continues as a well-defined log marker until the Nisku shelf margin. The stratigraphic significance of the Z Marker in delineating various oil bearing formations in Alberta were explained in great detail. The correct recognition and correlation of this marker was claimed to permit an understanding of basin evolution beyond that discernable from the existing lithostratigraphic nomenclature alone. 17 refs., 13 figs.

Influence of resistivity on energetic trapped particle-induced internal kink modes

International Nuclear Information System (INIS)

Biglari, H.; Chen, L.

1986-01-01

The influence of resistivity on energetic trapped particle-induced internal kink modes, dubbed ''fishbones'' in the literature, is explored. A general dispersion relation, which recovers the ideal theory in its appropriate limit, is derived and analyzed. An important implication of the theory for present generation fusion devices such as the Joint European Torus [Plasma Physics and Controlled Nuclear Fusion Research (IAEA, London, 1984), Vol I, p.11] is that they will be stable to fishbone activity

Trouble Upstairs: Reconstructing Permian-Triassic Climate during Siberian Traps Magmatism

Science.gov (United States)

Black, B. A.; Neely, R. R., III; Lamarque, J. F.; Elkins-Tanton, L. T.; Mills, M. J.

2014-12-01

The eruption of large igneous provinces can transfer significant masses of volatiles from Earth's interior to the atmosphere. What are the consequences of this degassing for habitability and extinction? In this presentation, we consider this question in the context of Siberian Traps magmatism, which has been shown to overlap within geochronologic uncertainty with catastrophic deterioration of Permian-Triassic marine and terrestrial ecosystems. To investigate the impacts of endogenic gases on climate, atmospheric chemistry, and ocean circulation, we conducted a series of numerical experiments with a comprehensive global model for the Permian-Triassic. Our simulations predict the intensity and distribution of acid rain and ozone depletion, with implications for terrestrial biota. We further explore feedbacks between sulfur emissions, transient cooling, and shifts in ocean circulation. We suggest that Siberian Traps magmatism may have triggered several distinct kill mechanisms in the oceans and on land, contributing to a complex combined pattern of environmental stress and latest Permian ecological failure.

Refining the timing of the MIS 5e signal, West Caicos, Bristish West Indies:implications for paleoclimatic interpretation of the stratigraphic record

Science.gov (United States)

Kerans, C.; Zahm, C.; Bachtel, S.; Hearty, P.; Cheng, H.

2017-12-01

The progressive refinement of the Last Interglacial (LIG) tropical carbonate record has focused attention on the dramatically abrupt and episodic nature of this critical approximate 12 ka time window. From initial carbonate platform flooding at 133 ka to rapid sea level fall and exposure at 118 ka, the majority of present-day Bahamian and Caribbean strata were produced in a remarkably similar pattern extending from Bermuda and the Bahamas through the Cayman Islands, Yucatan, and south to the Dominican Republic. The position of coral reefs and oolitic sands of the LIG to a first order fit the global insolation-driven climate warming signal. Less well accepted/resolved is the existence of two distinct SL peaks with an intervening sea level fall implying a non-orbitally forced climate shift during this broader highstand. West Caicos, a 10 x 5 km leeward island on the Caicos Platform is an excellent example of LIG carbonate stratigraphic complexity. We collected sub-meter-resolution whole-island airborn LIDAR and decimeter-resolution UAV-constructed DEM's of the western and southern coastal outcrops to serve as a base for decimeter-scale mapping of the MIS 11, 7?, 5e, and Holocene units of the island, with particular focus on the continuous 8.4 km west coast outcrop of the MIS 5e. Seventy-five AAR relative age assignments from ooid separates, pinned by 16 U/Th dates from corals coming from MIS stage 11, lower MIS 5e, and upper MIS 5e reefs helped establish the age model for the Pleistocene-Holocene stratigraphy. The lower MIS 5e reef system averages 128 ka with an onset age of 133 ka. Upper MIS 5e corals ranges from 123 ka to 116 ka, bracketing the intra-MIS 5e sea-level fall between to approximately 125 ka. The intra-MIS 5e fall is a distinct erosional unconformity across 5 km of continuous outcrop, truncating the upper 2.5 m of lower 5e reef. The complexity of MIS 5e record on West Caicos and in the Northern Atlantic and Caribbean platforms regionally provides

Stratigraphic units overlying the Zambales Ophiolite Complex (ZOC) in Luzon, (Philippines): Tectonostratigraphic significance and regional implications

Science.gov (United States)

Queaño, Karlo L.; Dimalanta, Carla B.; Yumul, Graciano P.; Marquez, Edanjarlo J.; Faustino-Eslava, Decibel V.; Suzuki, Shigeyuki; Ishida, Keisuke

2017-07-01

The Zambales Ophiolite Complex (ZOC) on the island of Luzon, Philippines is one of the most well-studied crust-mantle sequences in the region. Several massifs comprise the ZOC, one of which is the Coto Block overlain by clastic sedimentary units previously dated as Eocene. Geochronologic studies from diabase, granodiorites and other late-stage magmatic products similarly yielded the same age. Succeeding tectonic models have therefore all been grounded on the assumption that the entire ZOC is Eocene. Recent investigations, however, revealed the presence of chert blocks within the Early to Middle Miocene clastic formation overlying the Acoje Block in the northern part of the ophiolite complex. Radiolarians extracted from the cherts yielded a stratigraphic range that suggests a Late Jurassic to Early Cretaceous age. The recognition of a much older age than previously reported of the ZOC warrants a re-examination of its actual distribution and genesis. Correlating with other similarly-aged ophiolites, we suggest defining a western Mesozoic ophiolite belt, largely extending from the west-central portion of the archipelago to the northeastern tip of Luzon island. Tentatively, we attribute the Mesozoic ophiolitic and associated rocks in western Luzon to an arc-continent collision involving the Philippine Mobile Belt and the Palawan Microcontinental Block. In addition, differences in the clastic compositions of the Cenozoic sedimentary formations provide material not only for deciphering the ZOC's unroofing history but also for constraining the timing of province linkage. The intermittent appearance of lithic fragments and detrital minerals from the ophiolite in the units of the Middle Miocene Candelaria Limestone and the Late Miocene to Early Pliocene Sta. Cruz Formation indicates significant but geographically variable contributions from the ophiolite complex. In the northern Zambales Range, the Sta. Cruz Formation caps the Coto Block and the Acoje Block of the ZOC

Ion trap architectures and new directions

Science.gov (United States)

Siverns, James D.; Quraishi, Qudsia

2017-12-01

Trapped ion technology has seen advances in performance, robustness and versatility over the last decade. With increasing numbers of trapped ion groups worldwide, a myriad of trap architectures are currently in use. Applications of trapped ions include: quantum simulation, computing and networking, time standards and fundamental studies in quantum dynamics. Design of such traps is driven by these various research aims, but some universally desirable properties have lead to the development of ion trap foundries. Additionally, the excellent control achievable with trapped ions and the ability to do photonic readout has allowed progress on quantum networking using entanglement between remotely situated ion-based nodes. Here, we present a selection of trap architectures currently in use by the community and present their most salient characteristics, identifying features particularly suited for quantum networking. We also discuss our own in-house research efforts aimed at long-distance trapped ion networking.

A magnetic particle micro-trap for large trapping surfaces

KAUST Repository

Gooneratne, Chinthaka P.

2012-01-08

Manipulation of micron-size magnetic particles of the superparamagnetic type contributes significantly in many applications like controlling the antibody/antigen binding process in immunoassays. Specifically, more target biomolecules can be attached/tagged and analyzed since the three dimensional structure of the magnetic particles increases the surface to volume ratio. Additionally, such biomolecular-tagged magnetic particles can be easily manipulated by an external magnetic field due to their superparamagnetic behavior. Therefore, magnetic particle- based immunoassays are extensively applied in micro-flow cytometry. The design of a square-loop micro-trap as a magnetic particle manipulator as well as numerical and experimental analysis is presented. Experimental results showed that the micro-trap could successfully trap and concentrate magnetic particles from a large to a small area with a high spatial range.

A magnetic particle micro-trap for large trapping surfaces

KAUST Repository

Gooneratne, Chinthaka P.; Liang, Cai; Giouroudi, Ioanna; Kosel, Jü rgen

2012-01-01

Manipulation of micron-size magnetic particles of the superparamagnetic type contributes significantly in many applications like controlling the antibody/antigen binding process in immunoassays. Specifically, more target biomolecules can be attached/tagged and analyzed since the three dimensional structure of the magnetic particles increases the surface to volume ratio. Additionally, such biomolecular-tagged magnetic particles can be easily manipulated by an external magnetic field due to their superparamagnetic behavior. Therefore, magnetic particle- based immunoassays are extensively applied in micro-flow cytometry. The design of a square-loop micro-trap as a magnetic particle manipulator as well as numerical and experimental analysis is presented. Experimental results showed that the micro-trap could successfully trap and concentrate magnetic particles from a large to a small area with a high spatial range.

ATRAP - Progress Towards Trapped Antihydrogen

International Nuclear Information System (INIS)

Grzonka, D.; Goldenbaum, F.; Oelert, W.; Sefzick, T.; Zhang, Z.; Comeau, D.; Hessels, E.A.; Storry, C.H.; Gabrielse, G.; Larochelle, P.; Lesage, D.; Levitt, B.; Speck, A.; Haensch, T.W.; Pittner, H.; Walz, J.

2005-01-01

The ATRAP experiment at the CERN antiproton decelerator AD aims for a test of the CPT invariance by a high precision comparison of the 1s-2s transition in the hydrogen and the antihydrogen atom.Antihydrogen production is routinely operated at ATRAP and detailed studies have been performed in order to optimize the production efficiency of useful antihydrogen.For high precision measurements of atomic transitions cold antihydrogen in the ground state is required which must be trapped due to the low number of available antihydrogen atoms compared to the cold hydrogen beam used for hydrogen spectroscopy. To ensure a reasonable antihydrogen trapping efficiency a magnetic trap has to be superposed the nested Penning trap. First trapping tests of charged particles within a combined magnetic/Penning trap have started at ATRAP

ATRAP Progress Towards Trapped Antihydrogen

CERN Document Server

Grzonka, D; Gabrielse, G; Goldenbaum, F; Hänsch, T W; Hessels, E A; Larochelle, P; Le Sage, D; Levitt, B; Oelert, W; Pittner, H; Sefzick, T; Speck, A; Storry, C H; Walz, J; Zhang, Z

2005-01-01

The ATRAP experiment at the CERN antiproton decelerator AD aims for a test of the CPT invariance by a high precision comparison of the 1s‐2s transition in the hydrogen and the antihydrogen atom. Antihydrogen production is routinely operated at ATRAP and detailed studies have been performed in order to optimize the production efficiency of useful antihydrogen. For high precision measurements of atomic transitions cold antihydrogen in the ground state is required which must be trapped due to the low number of available antihydrogen atoms compared to the cold hydrogen beam used for hydrogen spectroscopy. To ensure a reasonable antihydrogen trapping efficiency a magnetic trap has to be superposed the nested Penning trap. First trapping tests of charged particles within a combined magnetic/Penning trap have started at ATRAP.

Status of THe-trap

Energy Technology Data Exchange (ETDEWEB)

Ketter, Jochen; Eronen, Tommi; Hoecker, Martin; Streubel, Sebastian; Blaum, Klaus [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Van Dyck, Robert S. Jr. [Department of Physics, University of Washington, Seattle, WA (United States)

2012-07-01

Originally developed at the University of Washington and relocated to the Max-Planck-Institut fuer Kernphysik in 2008, the Penning-trap spectrometer THe-Trap is specially tailored for a {sup 3}H/{sup 3}He mass-ratio measurement, from which the Q-value of the beta-decay of {sup 3}H to {sup 3}He can be derived. Improving the current best value by at least an order of magnitude will provide an important independent test parameter for the determination of the electron-antineutrino's mass by the Karlsruhe Tritium Neutrino Experiment (KATRIN). However, Penning-trap mass spectrometry has to be pushed to its limits in a dedicated experiment for a sufficiently accurate mass-ratio measurement with a relative uncertainty of 10{sup -11}. Unlike the closed-envelope, single-trap predecessor, the new spectrometer features an external ion source, owing to the radioactive nature of tritium, and two traps in order to speed up the measurement cycle. While the double-trap technique holds great promise, it also calls for more intricate procedures, such as ion transfer. Details about the recent progress of the experiment are given.

Servo control of an optical trap.

Science.gov (United States)

Wulff, Kurt D; Cole, Daniel G; Clark, Robert L

2007-08-01

A versatile optical trap has been constructed to control the position of trapped objects and ultimately to apply specified forces using feedback control. While the design, development, and use of optical traps has been extensive and feedback control has played a critical role in pushing the state of the art, few comprehensive examinations of feedback control of optical traps have been undertaken. Furthermore, as the requirements are pushed to ever smaller distances and forces, the performance of optical traps reaches limits. It is well understood that feedback control can result in both positive and negative effects in controlled systems. We give an analysis of the trapping limits as well as introducing an optical trap with a feedback control scheme that dramatically improves an optical trap's sensitivity at low frequencies.

Algae commensal community in Genlisea traps

Directory of Open Access Journals (Sweden)

Konrad Wołowski

2011-01-01

Full Text Available The community of algae occurring in Genlisea traps and on the external traps surface in laboratory conditions were studied. A total of 29 taxa were found inside the traps, with abundant diatoms, green algae (Chlamydophyceae and four morphotypes of chrysophytes stomatocysts. One morphotype is described as new for science. There are two ways of algae getting into Genlisea traps. The majority of those recorded inside the traps, are mobile; swimming freely by flagella or moving exuding mucilage like diatoms being ablate to colonize the traps themselves. Another possibility is transport of algae by invertebrates such as mites and crustaceans. In any case algae in the Genlisea traps come from the surrounding environment. Two dominant groups of algae (Chladymonas div. and diatoms in the trap environment, show ability to hydrolyze phosphomonoseters. We suggest that algae in carnivorous plant traps can compete with plant (host for organic phosphate (phosphomonoseters. From the spectrum and ecological requirements of algal species found in the traps, environment inside the traps seems to be acidic. However, further studies are needed to test the relations between algae and carnivorous plants both in laboratory conditions and in the natural environment. All the reported taxa are described briefly and documented with 74 LM and SEM micrographs.

Microfabricated linear Paul-Straubel ion trap

Science.gov (United States)

Mangan, Michael A [Albuquerque, NM; Blain, Matthew G [Albuquerque, NM; Tigges, Chris P [Albuquerque, NM; Linker, Kevin L [Albuquerque, NM

2011-04-19

An array of microfabricated linear Paul-Straubel ion traps can be used for mass spectrometric applications. Each ion trap comprises two parallel inner RF electrodes and two parallel outer DC control electrodes symmetric about a central trap axis and suspended over an opening in a substrate. Neighboring ion traps in the array can share a common outer DC control electrode. The ions confined transversely by an RF quadrupole electric field potential well on the ion trap axis. The array can trap a wide array of ions.

A not-so-big crisis: re-reading Silurian conodont diversity in a sequence-stratigraphic framework

Science.gov (United States)

Jarochowska, Emilia; Munnecke, Axel

2016-04-01

Conodonts are extensively used in Ordovician through Triassic biostratigraphy and fossil-based geochemistry. However, their distribution in rock successions is commonly taken at face value, without taking into account their diverse and poorly understood ecology. Multielement taxonomy, ontogenetic and environmental variability, difficulties in extraction, and relative rarity all contribute to the general lack of quantitative studies on conodont stratigraphic distribution and temporal turnover. With respect to Silurian conodonts, the concept of recurrent conodont extinction events - the so called Ireviken, Mulde and Lau events - has become a standard in the stratigraphic literature. The concept has been proposed based on qualitative observations of local extirpations of open-marine pelagic or nekto-benthic taxa and temporary dominance of shallow-water species in the Silurian succession of the Swedish island of Gotland. These changes coincided with positive carbon isotope excursions, abrupt facies shifts, "blooms" of benthic fauna, and changes in reef communities, which have all been combined into a general view of Silurian bio-geochemical events. This view posits a deterministic, reproducible pattern in Silurian conodont diversity, attributed to recurrent ecological or geochemical conditions. The growing body of sequence-stratigraphic interpretations across these events in Gotland and other sections worldwide indicate that in all cases the Silurian "events" are associated with rapid global regressions. This suggests that faunal changes such as the dominance of shallow-water, low-diversity conodont fauna and the increase of benthic invertebrate diversity and abundance represent predictable consequences of the variation in the completeness of the rock record and preservation potential of different environments. Our studies in Poland and Ukraine indicate that the magnitude of change in the taxonomic composition of conodont assemblages across the middle Silurian global

Devonian and Lower Carboniferous Conodonts of the Cantabrian Mountains (Spain) and their stratigraphic application

NARCIS (Netherlands)

Adrichem Boogaert, van H.A.

1967-01-01

A short review of the literature on the stratigraphy of the Devonian and the Lower Carboniferous of the Cantabrian Mountains precedes the report of the author's stratigraphic and palaeontologic observations in León: the Río Esla area (Gedinnian to Viséan), the central Cantabrian area (Famennian to

Impacts of trapping and banding activities on productivity of Roseate Terns (Sterna Dougallii)

Science.gov (United States)

Zingo, James M.

1998-01-01

, most of these effects disappeared after controlling for variation due to laying variables and other indices of parental age and quality. Trapping had little or no effect on later growth (indices of fledgling quality) and thus is unlikely to affect postfledging survival and fitness. For chicks whose parents were trapped, the sex of the adult(s), timing of trapping during the nesting stage, and interval between trapping events (if both parents were trapped) had little or no effect on growth. Daily or near-daily handling of chicks did not significantly affect their growth, prefledging survival, or postfledging survival. These results suggest that while trapping adult Roseate Terns can sometimes affect reproductive success and early chick growth and should be taken into account during research, trapping effects tend to be minor, short-lived, and unlikely to affect overall population health. While the full implications for population health and individual fitness are not entirely clear, there appears to be little cause for concern that trapping and banding activities are a significant problem for Roseate Terns. However, this qualitative assessment of the biological significance of trapping effects needs empirical testing. There remains a practical need to explore the ramifications of trapping effects and to consider local conditions when planning trapping activities. We also need to consider how investigator-induced effects might affect research results, and to balance potential effects of research activities against the value of the information gained.

Flow regimes in a trapped vortex cell

Science.gov (United States)

Lasagna, D.; Iuso, G.

2016-03-01

This paper presents results of an experimental investigation on the flow in a trapped vortex cell, embedded into a flat plate, and interacting with a zero-pressure-gradient boundary layer. The objective of the work is to describe the flow features and elucidate some of the governing physical mechanisms, in the light of recent investigations on flow separation control using vortex cells. Hot-wire velocity measurements of the shear layer bounding the cell and of the boundary layers upstream and downstream are reported, together with spectral and correlation analyses of wall-pressure fluctuation measurements. Smoke flow visualisations provide qualitative insight into some relevant features of the internal flow, namely a large-scale flow unsteadiness and possible mechanisms driving the rotation of the vortex core. Results are presented for two very different regimes: a low-Reynolds-number case where the incoming boundary layer is laminar and its momentum thickness is small compared to the cell opening, and a moderately high-Reynolds-number case, where the incoming boundary layer is turbulent and the ratio between the momentum thickness and the opening length is significantly larger than in the first case. Implications of the present findings to flow control applications of trapped vortex cells are also discussed.

Two-baffle trap for macroparticles

International Nuclear Information System (INIS)

Aksyonov, D.S.

2014-01-01

In this work, properties of two-baffle macroparticle traps were investigated. These properties are needed for designing and optimization of vacuum arc plasma filters. The dependencies between trap geometry parameters and its ability to absorb macroparticles were found. Calculations made allow one to predict the behaviour of filtering abilities of separators containing such traps in their design. Recommendations regarding the use of two-baffle traps in filters of different builds are given

Harmless nectar source or deadly trap: Nepenthes pitchers are activated by rain, condensation and nectar.

Science.gov (United States)

Bauer, Ulrike; Bohn, Holger F; Federle, Walter

2008-02-07

The leaves of Nepenthes pitcher plants are specialized pitfall traps which capture and digest arthropod prey. In many species, insects become trapped by 'aquaplaning' on the wet pitcher rim (peristome). Here we investigate the ecological implications of this capture mechanism in Nepenthes rafflesiana var. typica. We combine meteorological data and continuous field measurements of peristome wetness using electrical conductance with experimental assessments of the pitchers' capture efficiency. Our results demonstrate that pitchers can be highly effective traps with capture rates as high as 80% but completely ineffective at other times. These dramatic changes are due to the wetting condition of the peristome. Variation of peristome wetness and capture efficiency was perfectly synchronous, and caused by rain, condensation and nectar secreted from peristome nectaries. The presence of nectar on the peristome increased surface wetness mainly indirectly by its hygroscopic properties. Experiments confirmed that pitchers with removed peristome nectaries remained generally drier and captured prey less efficiently than untreated controls. This role of nectar in prey capture represents a novel function of plant nectar. We propose that the intermittent and unpredictable activation of Nepenthes pitcher traps facilitates ant recruitment and constitutes a strategy to maximize prey capture.

Ion Trap Quantum Computing

Science.gov (United States)

2011-12-01

variations of ion traps, including (1) the cylindrically symmetric 3D ring trap; (2) the linear trap with a combination of cavity QED; (#) the symmetric...concepts of quantum information. The major demonstration has been the test of a Bell inequality as demonstrated by Rowe et al. [50] and a decoherence...famous physics experiment [62]. Wolfgang Paul demonstrated a similar apparatus during his Nobel Prize speech [63]. This device is hyperbolic- parabolic

Ecological implications of organic carbon dynamics in the traps of aquatic carnivorous Utricularia plants

Czech Academy of Sciences Publication Activity Database

Sirová, Dagmara; Borovec, Jakub; Picek, T.; Adamec, Lubomír; Nedbalová, Linda; Vrba, Jaroslav

2011-01-01

Roč. 38, č. 7 (2011), s. 583-593 ISSN 1445-4408 R&D Projects: GA ČR(CZ) GAP504/11/0783; GA ČR GP206/05/P520 Institutional research plan: CEZ:AV0Z60050516; CEZ:AV0Z60170517 Keywords : biodegradability * trap fluid composition * organic acids Subject RIV: EF - Botanics Impact factor: 2.929, year: 2011

Versatile electrostatic trap

NARCIS (Netherlands)

van Veldhoven, J.; Bethlem, H.L.; Schnell, M.; Meijer, G.

2006-01-01

A four electrode electrostatic trap geometry is demonstrated that can be used to combine a dipole, quadrupole, and hexapole field. A cold packet of ND315 molecules is confined in both a purely quadrupolar and hexapolar trapping field and additionally, a dipole field is added to a hexapole field to

Trapping saturation of the bump-on-tail instability and electrostatic harmonic excitation in Earth's foreshock

International Nuclear Information System (INIS)

Klimas, A.J.

1990-01-01

Trapping saturation of the bump-on-tail instability is discussed using electron plasma Vlasov simulation results. The role of electrostatic harmonic excitation is considered in detail and shown to play a decisive role in the saturation of the instability. An extensive discussion of the simulation results is given to show that the results are not significantly limited by the finite number of Fourier modes used nor by the discrete distribution of those modes in wave number. It is argued that in the leading edge of Earth's electron foreshock a narrow wave number band of unstable field modes leads to trapping saturation of the bump-on-tail instability while simultaneously exciting electrostatic plasma waves at harmonics of the plasma frequency in simialr narrow bands of shorter wavelengths. The argument is based (1) on the observations of Lacombe et al. (1985), who found intense plasma waves at the leading edge of the foreshock with a spectral distribution sufficiently narrow to trap particles in resonance with the waves, and (2) on numerical simulations of the foreshock electron plasma which indicate that trapping saturation of the bump-on-tail instability leads to phase space vortex formation with consequent excitation of electrostatic harmonics. Thus it is suggested that observations of electrostatic harmonics in the leading edge of the foreshock would strongly implicate trapping as the saturation mechanism for the bump-on-tail instability in that region

A circularly polarized optical dipole trap and other developments in laser trapping of atoms

Science.gov (United States)

Corwin, Kristan Lee

Several innovations in laser trapping and cooling of alkali atoms are described. These topics share a common motivation to develop techniques for efficiently manipulating cold atoms. Such advances facilitate sensitive precision measurements such as parity non- conservation and 8-decay asymmetry in large trapped samples, even when only small quantities of the desired species are available. First, a cold, bright beam of Rb atoms is extracted from a magneto-optical trap (MOT) using a very simple technique. This beam has a flux of 5 × 109 atoms/s and a velocity of 14 m/s, and up to 70% of the atoms in the MOT were transferred to the atomic beam. Next, a highly efficient MOT for radioactive atoms is described, in which more than 50% of 221Fr atoms contained in a vapor cell are loaded into a MOT. Measurements were also made of the 221Fr 7 2P1/2 and 7 2P3/2 energies and hyperfine constants. To perform these experiments, two schemes for stabilizing the frequency of the light from a diode laser were developed and are described in detail. Finally, a new type of trap is described and a powerful cooling technique is demonstrated. The circularly polarized optical dipole trap provides large samples of highly spin-polarized atoms, suitable for many applications. Physical processes that govern the transfer of large numbers of atoms into the trap are described, and spin-polarization is measured to be 98(1)%. In addition, the trap breaks the degeneracy of the atomic spin states much like a magnetic trap does. This allows for RF and microwave cooling via both forced evaporation and a Sisyphus mechanism. Preliminary application of these techniques to the atoms in the circularly polarized dipole trap has successfully decreased the temperature by a factor of 4 while simultaneously increasing phase space density.

Efficacy of multifunnel traps for capturing emerald ash borer (Coleoptera: Buprestidae): effect of color, glue, and other trap coatings.

Science.gov (United States)

Francese, Joseph A; Fraser, Ivich; Lance, David R; Mastro, Victor C

2011-06-01

Tens of thousands of adhesive-coated purple prism traps are deployed annually in the United States to survey for the invasive emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae). A reusable, more user-friendly trap is desired by program managers, surveyors, and researchers. Field assays were conducted in southeastern Michigan to ascertain the feasibility of using nonsticky traps as survey and detection tools for emerald ash borer. Three nonsticky trap designs, including multifunnel (Lindgren), modified intercept panel, and drainpipe (all painted purple) were compared with the standard purple prism trap; no statistical differences in capture of emerald ash borer adults were detected between the multifunnel design and the prism. In subsequent color comparison assays, both green- and purple-painted multifunnel traps (and later, plastic versions of these colors) performed as well or better than the prism traps. Multifunnel traps coated with spray-on adhesive caught more beetles than untreated traps. The increased catch, however, occurred in the traps' collection cups and not on the trap surface. In a separate assay, there was no significant difference detected between glue-coated traps and Rain-X (normally a glass treatment)-coated traps, but both caught significantly more A. planipennis adults than untreated traps.

Première caractérisation palynologique du Trias moyen dans le Haut Atlas ; implications pour l'initiation du rifting téthysien au Maroc

Science.gov (United States)

El Arabi, El Hassane; Diez, José Bienvenido; Broutin, Jean; Essamoud, Rachid

2006-07-01

The Middle Anisian has been palynologically characterized for the first time, at the whole Moroccan scale, in the High Atlas of Marrakech. The stratigraphic, tectonic and paleogeographic implications of this discovery are analysed. To cite this article: E.H. El Arabi et al., C. R. Geoscience 338 (2006).

Particle trapping in stimulated scattering processes

International Nuclear Information System (INIS)

Karttunen, S.J.; Heikkinen, J.A.

1981-01-01

Particle trapping effects on stimulated Brillouin and Raman scattering are investigated. A time and space dependent model assumes a Maxwellian plasma which is taken to be homogeneous in the interaction region. Ion trapping has a rather weak effect on stimulated Brillouin scattering and large reflectivities are obtained even in strong trapping regime. Stimulated Raman scattering is considerably reduced by electron trapping. Typically 15-20 times larger laser intensities are required to obtain same reflectivity levels than without trapping. (author)

Tectonic evolution of the Paranoá basin: New evidence from gravimetric and stratigraphic data

Science.gov (United States)

Martins-Ferreira, Marco Antonio Caçador; Campos, José Eloi Guimarães; Von Huelsen, Monica Giannoccaro

2018-06-01

Field gravimetric and stratigraphic surveys were conducted with the aim to constraint the mechanisms responsible for the initiation of the Stenian-Tonian Paranoá basin, central Brazil, a subject not yet studied in detail. The Paranoá Group crops out in the external zone of the Brasília Belt, a Neoproterozoic orogen in the western margin of the São Francisco Craton. Detailed geological mapping confirmed the existence of a regional scale fault that controlled sedimentation of the Paranoá Group during the deposition of its basal formations, revealing important details about basin initiation and early evolution. Gravimetric modeling indicates the existence of paleorift structures beneath the Paranoá sequence in the study area. Results from both stratigraphic and gravimetric surveys show strong evidence of mechanical subsidence by faulting during basin initiation. Unsorted, angular, clasts cut by quartz veins and brecciated boulders present in the basal conglomerate, support this hypothesis. Basin initiation faults coincide with deeper paleorift faults and are thus interpreted as reactivations of the older Statherian Araí Rift. The reactivations favored an initial regime of mechanical subsidence, dominated by the development of epirogenic arches subsiding at different rates. Apart from faulting activity, the post-basal sequence presents no evidence of rift environment in the strict sense. Besides, the great lateral continuity and relatively constant thickness of facies, indicate that an initial mechanic subsidence rapidly gave way to flexural subsidence during subsequent stages of basin evolution. The Paranoá Group do not present reliable characteristics that would allow its strict classification as a passive margin. Its main stratigraphic characteristics, tectonic location and basement architecture, indicate that the Paranoá Group was deposited in a cratonic margin basin, and may have been either connected to a passive margin basin at times of sea level rise

Dynamic array of dark optical traps

DEFF Research Database (Denmark)

Daria, V.R.; Rodrigo, P.J.; Glückstad, J.

2004-01-01

A dynamic array of dark optical traps is generated for simultaneous trapping and arbitrary manipulation of multiple low-index microstructures. The dynamic intensity patterns forming the dark optical trap arrays are generated using a nearly loss-less phase-to-intensity conversion of a phase......-encoded coherent light source. Two-dimensional input phase distributions corresponding to the trapping patterns are encoded using a computer-programmable spatial light modulator, enabling each trap to be shaped and moved arbitrarily within the plane of observation. We demonstrate the generation of multiple dark...... optical traps for simultaneous manipulation of hollow "air-filled" glass microspheres suspended in an aqueous medium. (C) 2004 American Institute of Physics....

Trapped antihydrogen

CERN Document Server

Butler, E; Ashkezari, M D; Baquero-Ruiz, M; Bertsche, W; Bowe, P D; Cesar, C L; Chapman, S; Charlton, M; Deller, A; Eriksson, S; Fajans, J; Friesen, T; Fujiwara, M C; Gill, D R; Gutierrez, A; Hangst, J S; Hardy, W N; Hayden, M E; Humphries, A J; Hydomako, R; Jenkins, M J; Jonsell, S; Jørgensen, L V; Kemp, S L; Kurchaninov, L; Madsen, N; Menary, S; Nolan, P; Olchanski, K; Olin, A; Povilus, A; Pusa, P; Rasmussen, C Ø; Robicheaux, F; Sarid, E; Seif el Nasr, S; Silveira, D M; So, C; Storey, J W; Thompson, R I; van der Werf, D P; Wurtele, J S; Yamazaki,Y

2012-01-01

Precision spectroscopic comparison of hydrogen and antihydrogen holds the promise of a sensitive test of the Charge-Parity-Time theorem and matter-antimatter equivalence. The clearest path towards realising this goal is to hold a sample of antihydrogen in an atomic trap for interrogation by electromagnetic radiation. Achieving this poses a huge experimental challenge, as state-of-the-art magnetic-minimum atom traps have well depths of only ∼1 T (∼0.5 K for ground state antihydrogen atoms). The atoms annihilate on contact with matter and must be ‘born’ inside the magnetic trap with low kinetic energies. At the ALPHA experiment, antihydrogen atoms are produced from antiprotons and positrons stored in the form of non-neutral plasmas, where the typical electrostatic potential energy per particle is on the order of electronvolts, more than 104 times the maximum trappable kinetic energy. In November 2010, ALPHA published the observation of 38 antiproton annihilations due to antihydrogen atoms that had been ...

Stratigraphic and structural configuration of the Navajo (Jurassic) through Ouray (Mississippian-Devonian) formations in the vicinity of Davis and Lavender Canyons, southeastern Utah

International Nuclear Information System (INIS)

McCleary, J.R.; Romie, J.E.

1986-04-01

This study developed a three-dimensional computer model of stratigraphic and structural relationships within a 3497-km 2 (1350-mi 2 ) study area centered on the proposed site for a high-level nuclear waste repository in southeastern Utah. The model consists of a sequence of internally reconciled isopach and structure contour maps horizontally registered and stored in stratigraphic order. This model can be used to display cross sections, perspective block diagrams, or fence diagrams at any orientation; estimate depth of formation contacts and thicknesses for any new stratigraphic or hydrologic boreholes; facilitate ground-water modeling studies; and evaluate the structural and stratigraphic evolution of the study area. This study also includes limited evaluations of aquifer continuity in the Elephant Canyon and Honaker Trail Formations, and of salt dissolution and flowage features as interpreted from geophysical logs. The study identified a long history of movement in the fault system in the north-central part of the study area and a major salt flowage feature in the northeastern part. It describes the Elephant Canyon Formation aquifer as laterally limited, the Honaker Trail Formation aquifer as fairly continuous over the area, and Beef Basin in the southern part of the area as a probable dissolution feature. It also concludes that the Shay-Bridger Jack-Salt Creek Graben system is apparently a vertically continuous feature between the basement and ground surface. No stratigraphic or structural discontinuities were detected in the vicinity of Davis Canyon that appear to be detrimental to the siting of a waste repository

Spatial mismatch between sea lamprey behaviour and trap location explains low success at trapping for control

Science.gov (United States)

Rous, Andrew M.; McLean, Adrienne R.; Barber, Jessica; Bravener, Gale; Castro-Santos, Theodore; Holbrook, Christopher M.; Imre, Istvan; Pratt, Thomas C.; McLaughlin, Robert L.

2017-01-01

Crucial to the management of invasive species is understanding space use and the environmental features affecting space use. Improved understanding of space use by invasive sea lamprey (Petromyzon marinus) could help researchers discern why trap success in large rivers is lower than needed for effective control. We tested whether manipulating discharge nightly could increase trap success at a hydroelectric generating station on the St. Marys River. We quantified numbers of acoustically tagged sea lampreys migrating up to, and their space use at, the hydroelectric generating station. In 2011 and 2012, 78% and 68%, respectively, of tagged sea lampreys reached the generating station. Sea lampreys were active along the face, but more likely to occur at the bottom and away from the traps near the surface, especially when discharge was high. Our findings suggest that a low probability of encountering traps was due to spatial (vertical) mismatch between space use by sea lamprey and trap locations and that increasing discharge did not alter space use in ways that increased trap encounter. Understanding space use by invasive species can help managers assess the efficacy of trapping and ways of improving trapping success.

A MATLAB®-based program for 3D visualization of stratigraphic setting and subsidence evolution of sedimentary basins: example application to the Vienna Basin

Science.gov (United States)

Lee, Eun Young; Novotny, Johannes; Wagreich, Michael

2015-04-01

In recent years, 3D visualization of sedimentary basins has become increasingly popular. Stratigraphic and structural mapping is highly important to understand the internal setting of sedimentary basins. And subsequent subsidence analysis provides significant insights for basin evolution. This study focused on developing a simple and user-friendly program which allows geologists to analyze and model sedimentary basin data. The developed program is aimed at stratigraphic and subsidence modelling of sedimentary basins from wells or stratigraphic profile data. This program is mainly based on two numerical methods; surface interpolation and subsidence analysis. For surface visualization four different interpolation techniques (Linear, Natural, Cubic Spline, and Thin-Plate Spline) are provided in this program. The subsidence analysis consists of decompaction and backstripping techniques. The numerical methods are computed in MATLAB® which is a multi-paradigm numerical computing environment used extensively in academic, research, and industrial fields. This program consists of five main processing steps; 1) setup (study area and stratigraphic units), 2) loading of well data, 3) stratigraphic modelling (depth distribution and isopach plots), 4) subsidence parameter input, and 5) subsidence modelling (subsided depth and subsidence rate plots). The graphical user interface intuitively guides users through all process stages and provides tools to analyse and export the results. Interpolation and subsidence results are cached to minimize redundant computations and improve the interactivity of the program. All 2D and 3D visualizations are created by using MATLAB plotting functions, which enables users to fine-tune the visualization results using the full range of available plot options in MATLAB. All functions of this program are illustrated with a case study of Miocene sediments in the Vienna Basin. The basin is an ideal place to test this program, because sufficient data is

How much CO2 is trapped in carbonate minerals of a natural CO2 occurrence?

Science.gov (United States)

Király, Csilla; Szabó, Zsuzsanna; Szamosfalvi, Ágnes; Cseresznyés, Dóra; Király, Edit; Szabó, Csaba; Falus, György

2017-04-01

Carbon Capture and Storage (CCS) is a transitional technology to decrease CO2 emissions from human fossil fuel usage and, therefore, to mitigate climate change. The most important criteria of a CO2 geological storage reservoir is that it must hold the injected CO2 for geological time scales without its significant seepage. The injected CO2 undergoes physical and chemical reactions in the reservoir rocks such as structural-stratigraphic, residual, dissolution or mineral trapping mechanisms. Among these, the safest is the mineral trapping, when carbonate minerals such as calcite, ankerite, siderite, dolomite and dawsonite build the CO2 into their crystal structures. The study of natural CO2 occurrences may help to understand the processes in CO2 reservoirs on geological time scales. This is the reason why the selected, the Mihályi-Répcelak natural CO2 occurrence as our research area, which is able to provide particular and highly significant information for the future of CO2 storage. The area is one of the best known CO2 fields in Central Europe. The main aim of this study is to estimate the amount of CO2 trapped in the mineral phase at Mihályi-Répcelak CO2 reservoirs. For gaining the suitable data, we apply petrographic, major and trace element (microprobe and LA-ICP-MS) and stable isotope analysis (mass spectrometry) and thermodynamic and kinetic geochemical models coded in PHREEQC. Rock and pore water compositions of the same formation, representing the pre-CO2 flooding stages of the Mihályi-Répcelak natural CO2 reservoirs are used in the models. Kinetic rate parameters are derived from the USGS report of Palandri and Kharaka (2004). The results of petrographic analysis show that a significant amount of dawsonite (NaAlCO3(OH)2, max. 16 m/m%) precipitated in the rock due to its reactions with CO2 which flooded the reservoir. This carbonate mineral alone traps about 10-30 kg/m3 of the reservoir rock from the CO2 at Mihályi-Répcelak area, which is an

St. Croix trap study

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The data set contains detailed information about the catch from 600 trap stations around St. Croix. Data fields include species caught, size data, trap location...

Prehistoric floods on the Tennessee River—Assessing the use of stratigraphic records of past floods for improved flood-frequency analysis

Science.gov (United States)

Harden, Tessa M.; O'Connor, Jim E.

2017-06-14

Stratigraphic analysis, coupled with geochronologic techniques, indicates that a rich history of large Tennessee River floods is preserved in the Tennessee River Gorge area. Deposits of flood sediment from the 1867 peak discharge of record (460,000 cubic feet per second at Chattanooga, Tennessee) are preserved at many locations throughout the study area at sites with flood-sediment accumulation. Small exposures at two boulder overhangs reveal evidence of three to four other floods similar in size, or larger, than the 1867 flood in the last 3,000 years—one possibly as much or more than 50 percent larger. Records of floods also are preserved in stratigraphic sections at the mouth of the gorge at Williams Island and near Eaves Ferry, about 70 river miles upstream of the gorge. These stratigraphic records may extend as far back as about 9,000 years ago, giving a long history of Tennessee River floods. Although more evidence is needed to confirm these findings, a more in-depth comprehensive paleoflood study is feasible for the Tennessee River.

Trapping and Probing Antihydrogen

Energy Technology Data Exchange (ETDEWEB)

Wurtele, Jonathan [UC Berkeley and LBNL

2013-03-27

Precision spectroscopy of antihydrogen is a promising path to sensitive tests of CPT symmetry. The most direct route to achieve this goal is to create and probe antihydrogen in a magnetic minimum trap. Antihydrogen has been synthesized and trapped for 1000s at CERN by the ALPHA Collaboration. Some of the challenges associated with achieving these milestones will be discussed, including mixing cryogenic positron and antiproton plasmas to synthesize antihydrogen with kinetic energy less than the trap potential of .5K. Recent experiments in which hyperfine transitions were resonantly induced with microwaves will be presented. The opportunity for gravitational measurements in traps based on detailed studies of antihydrogen dynamics will be described. The talk will conclude with a discussion future antihydrogen research that will use a new experimental apparatus, ALPHA-I.

Continuous Arsine Detection Using a Peltier-Effect Cryogenic Trap To Selectively Trap Methylated Arsines.

Science.gov (United States)

Chen, Guoying; Lai, Bunhong; Mao, Xuefei; Chen, Tuanwei; Chen, Miaomiao

2017-09-05

Hydride generation (HG) is an effective technique that eliminates interfering matrix species and enables hydride separation. Arsenic speciation analysis can be fulfilled by cryogenic trapping (CT) based on boiling points of resulting arsines using liquid nitrogen (LN 2 ) as a coolant. In this work, LN 2 was replaced by the thermoelectric effect using a cryogenic trap that consisted of a polytetrafluoroethylene (PTFE) body sandwiched by two Peltier modules. After the trap was precooled, the arsines flew along a zigzag channel in the body and reached a sorbent bed of 0.2 g of 15% OV-3 on Chromosorb W-AW-DMCS imbedded near the exit of the trap. CH 3 AsH 2 and (CH 3 ) 2 AsH were trapped, while AsH 3 , that passed the trap unaffected, was detected by atomic fluorescence spectrometry. Continuous operation led to enhanced throughput. For inorganic As, the limit of detection (LOD) was 1.1 ng/g and recovery was 101.0 ± 1.1%. Monomethylarsonic acid and dimethylarsinic acid did not interfere with 0.2 ± 1.2% and -0.3 ± 0.5% recoveries, respectively.

Seismic stratigraphic architecture of the Disko Bay trough-mouth fan system, West Greenland

Science.gov (United States)

Hofmann, Julia C.; Knutz, Paul C.

2015-04-01

Spatial and temporal changes of the Greenland Ice Sheet on the continental shelf bordering Baffin Bay remain poorly constrained. Then as now, fast-flowing ice streams and outlet glaciers have played a key role for the mass balance and stability of polar ice sheets. Despite their significance for Greenland Ice Sheet dynamics and evolution, our understanding of their long-term behaviour is limited. The central West Greenland margin is characterized by a broad continental shelf where a series of troughs extend from fjords to the shelf margin, acting as focal points for trough-mouth fan (TMF) accummulations. The sea-ward bulging morphology and abrupt shelf-break of these major depositional systems is generated by prograding depocentres that formed during glacial maxima when ice streams reached the shelf edge, delivering large amounts of subglacial sediment onto the continental slope (Ó Cofaigh et al., 2013). The aim of this study is to unravel the seismic stratigraphic architecture and depositional processes of the Disko Bay TMF, aerially the largest single sedimentary system in West Greenland, using 2D and 3D seismic reflection data, seabed bathymetry and stratigraphic information from exploration well Hellefisk-1. The south-west Disko Bay is intersected by a deep, narrow trough, Egedesminde Dyb, which extends towards the southwest and links to the shallower and broader cross-shelf Disko Trough (maximum water depths of > 1000 m and a trough length of c. 370 km). Another trough-like depression (trough length of c. 120 km) in the northern part of the TMF, indicating a previous position of the ice stream, can be distinguished on the seabed topographic map and the seismic images. The Disko Bay TMF itself extends from the shelf edge down to the abyssal plain (abyssal floor depths of 2000 m) of the southern Baffin Bay. Based on seismic stratigraphic configurations relating to reflection terminations, erosive patterns and seismic facies (Mitchum et al., 1977), the TMF

3D seismic investigation of the structural and stratigraphic characteristics of the Pagasa Wedge, Southwest Palawan Basin, Philippines, and their tectonic implications

Science.gov (United States)

Ilao, Kimberly A.; Morley, Christopher K.; Aurelio, Mario A.

2018-04-01

The Pagasa Wedge is a poorly imaged deepwater orogenic wedge that has been variously interpreted as representing an accretionary prism, a former accretionary prism modified by thrusting onto a thinned continental margin, and a gravity-driven fold-thrust belt. This study, using 2D and 3D seismic data, together with well information indicates that at least the external part of the wedge is dominantly composed of mass transport complexes, capped by syn-kinematic sediments that have thrusts and normal faults superimposed upon them. Drilling shows that despite stratigraphic repetition of Eocene Middle Miocene units, there is stratigraphic omission of Oligocene and Early Miocene units. This absence suggests that mass transport processes have introduced the Eocene section into the wedge rather than tectonic thrusting. The accretionary prism stage (Oligocene) of the Central Palawan Ophiolite history appears to be marked by predominantly north-vergent deformation. The Deep Regional Unconformity (∼17 Ma) likely indicates the approximate time when obduction ceased in Palawan. The Pagasa Wedge is a late-stage product of the convergence history that was active in its final phase sometime above the top of the Nido Limestone (∼16 Ma) and the base of the Tabon Limestone in the Aboabo-A1X well (∼9 Ma). The top of the wedge is traditionally associated with the Middle Miocene Unconformity (MMU), However the presence of multiple unconformities, diachronous formation tops, local tectonic unconformities and regional diachronous events (e.g. migrating forebulges) all suggest simply giving a single age (or assigning a single unconformity, such as the MMU as defining the top of the Pagasa Wedge is inappropriate. The overall NE-SW trend of the wedge, and the dominant NW transport of structures within the wedge diverge from the more northerly transport direction determined from outcrops in Palawan, and also from the Nido Limestone in the SW part of the Pagasa Wedge. Possibly this NW

Treinta y Tres stratigraphic terrain: ex Cuchilla Dionisio terrain. Uruguay

International Nuclear Information System (INIS)

Bossi, J.

2010-01-01

From 1998 we are discussing if the eastern area of ZCSB is an allochtonous block named TCD or if it belongs to Dom Feliciano belt with an age of 500 - 700 Ma. This crustal block is difficult to study because Laguna Merin Graben cut it in two around 4000 k m2 crustal fragments distant s more de 100 km between them. Southern block which was named T PE by Masquelín (2006) was demonstrated as allochtonous by Bossi and Gaucher (2004) destroying the Cdf model but seriously complicating the stratigraphic terminology. It is proposed to do some changes in order to profit the general agreement about allochtomy. The CDT with change by Treinta y Tres terrane; T PE become sub - terrain Punta del Este; sub - terrain Cuchilla Dionisio for the septetrional block. From 1998 we are discussing if the eastern area of ZCSB is an allochtonous block named TCD or if it belongs to Dom Feliciano belt with an age of 500 - 700 Ma. This crustal block is difficult to study because Laguna Merín Graben cut it in two around 4000 k m2 crustal fragments distant s more de 100 km between them. Southern block which was named T PE by Masquelín (2006) was demonstrated as allochtonous by Bossi and Gaucher (2004) destroying the CDF model but seriously complicating the stratigraphic terminology. It is proposed to do some changes in order to profit the general agreement about allochtomy. The CDT with change by Treinta y Tres terrain; TPE become sub - terrain Punta del Este; sub - terrain Cuchilla Dionisio for the septetrional block

Trapping tsetse flies on water

Directory of Open Access Journals (Sweden)

Laveissière C.

2011-05-01

Full Text Available Riverine tsetse flies such as Glossina palpalis gambiensis and G. tachinoides are the vectors of human and animal trypanosomoses in West Africa. Despite intimate links between tsetse and water, to our knowledge there has never been any attempt to design trapping devices that would catch tsetse on water. In mangrove (Guinea one challenging issue is the tide, because height above the ground for a trap is a key factor affecting tsetse catches. The trap was mounted on the remains of an old wooden dugout, and attached with rope to nearby branches, thereby allowing it to rise and fall with the tide. Catches showed a very high density of 93.9 flies/”water-trap”/day, which was significantly higher (p < 0.05 than all the catches from other habitats where the classical trap had been used. In savannah, on the Comoe river of South Burkina Faso, the biconical trap was mounted on a small wooden raft anchored to a stone, and catches were compared with the classical biconical trap put on the shores. G. p. gambiensis and G. tachinoides densities were not significantly different from those from the classical biconical one. The adaptations described here have allowed to efficiently catch tsetse on the water, which to our knowledge is reported here for the first time. This represents a great progress and opens new opportunities to undertake studies on the vectors of trypanosomoses in mangrove areas of Guinea, which are currently the areas showing the highest prevalences of sleeping sickness in West Africa. It also has huge potential for tsetse control using insecticide impregnated traps in savannah areas where traps become less efficient in rainy season. The Guinean National control programme has already expressed its willingness to use such modified traps in its control campaigns in Guinea, as has the national PATTEC programme in Burkina Faso during rainy season.

Morphodynamics and stratigraphic architecture of shelf-edge deltas subject to constant vs. dynamic environmental forcings

Science.gov (United States)

Straub, K. M.

2017-12-01

When deltas dock at the edge of continental margins they generally construct thick stratigraphic intervals and activate channelized continental slope systems. Deposits of shelf-edge deltas have the capacity to store detailed paleo-environmental records, given their location in the source to sink system. However, present day highstand sea-level conditions have pushed most deltaic systems well inbound of their shelf-edges, making it difficult to study their space-time dynamics and resulting stratigraphic products. Several competing theories describe how deltas and their downslope environments respond to sea-level cycles of varying magnitude and periodicity. We explore these hypotheses in a physical experiment where the topographic evolution of a coupled delta and downdip slope system was monitored at high temporal and spatial resolution. The experiment had three stages. In the first stage a delta aggraded at the shelf-edge under constant water and sediment supply, in addition to a constant generation of accommodation through a sea-level rise. In the second stage the sediment transport system responded to low magnitude and high frequency sea-level cycles. Finally, in the third stage the transport system responded to a high magnitude and long period sea-level cycle. In each stage, fine sediment from the input grain size distribution and dissolved salt in the input water supply promoted plunging hyperpycnal flows. Specifically, we compare the mean and temporal variability of the sediment delivered to the slope system between stages. In addition, we compare stratigraphic architecture and sediment sizes delivered to the slope system in each stage. These results are used to improve inversion of slope deposits for paleo-environmental forcings.

Controlling trapping potentials and stray electric fields in a microfabricated ion trap through design and compensation

International Nuclear Information System (INIS)

Charles Doret, S; Amini, Jason M; Wright, Kenneth; Volin, Curtis; Killian, Tyler; Ozakin, Arkadas; Denison, Douglas; Hayden, Harley; Pai, C-S; Slusher, Richart E; Harter, Alexa W

2012-01-01

Recent advances in quantum information processing with trapped ions have demonstrated the need for new ion trap architectures capable of holding and manipulating chains of many (>10) ions. Here we present the design and detailed characterization of a new linear trap, microfabricated with scalable complementary metal-oxide-semiconductor (CMOS) techniques, that is well-suited to this challenge. Forty-four individually controlled dc electrodes provide the many degrees of freedom required to construct anharmonic potential wells, shuttle ions, merge and split ion chains, precisely tune secular mode frequencies, and adjust the orientation of trap axes. Microfabricated capacitors on dc electrodes suppress radio-frequency pickup and excess micromotion, while a top-level ground layer simplifies modeling of electric fields and protects trap structures underneath. A localized aperture in the substrate provides access to the trapping region from an oven below, permitting deterministic loading of particular isotopic/elemental sequences via species-selective photoionization. The shapes of the aperture and radio-frequency electrodes are optimized to minimize perturbation of the trapping pseudopotential. Laboratory experiments verify simulated potentials and characterize trapping lifetimes, stray electric fields, and ion heating rates, while measurement and cancellation of spatially-varying stray electric fields permits the formation of nearly-equally spaced ion chains. (paper)

Using Outcrop Exposures on the Road to Yellowknife Bay to Build a Stratigraphic Column, Gale Crater, Mars

Science.gov (United States)

Stack, K. M.; Grotzinger, J. P.; Sumner, D.; Ehlmann, B. L.; Milliken, R. E.; Eigenbrode, J. L.; Gupta, S.; Williams, R. M. E.; Kah, L. C.; Lewis, K. W.

2013-01-01

Since landing in Gale Crater on August 5, 2012, the Curiosity rover has driven 450 m east, descending approximately 15 m in elevation from the Bradbury landing site to Yellowknife Bay. Outcrop exposure along this drive has been discontinuous, but isolated outcrops may represent windows into underlying inplace stratigraphy. This study presents an inventory of outcrops targeted by Curiosity (Figs. 1-2), grouped by lithological properties observed in Mastcam and Navcam imagery. Outcrop locations are placed in a stratigraphic context using orbital imagery and first principles of stratigraphy. The stratigraphic models presented here represent an essential first step in understanding the relative age relationships of lithological units encountered at the Curiosity landing site. Such observations will provide crucial context for assessing habitability potential of ancient Gale crater environments and organic matter preservation.

Characteristics of single-atom trapping in a magneto-optical trap with a high magnetic-field gradient

International Nuclear Information System (INIS)

Yoon, Seokchan; Choi, Youngwoon; Park, Sangbum; Ji, Wangxi; Lee, Jai-Hyung; An, Kyungwon

2007-01-01

A quantitative study on characteristics of a magneto-optical trap with a single or a few atoms is presented. A very small number of 85 Rb atoms were trapped in a micron-size magneto-optical trap with a high magnetic-field gradient. In order to find the optimum condition for a single-atom trap, we have investigated how the number of atoms and the size of atomic cloud change as various experimental parameters, such as a magnetic-field gradient and the trapping laser intensity and detuning. The averaged number of atoms was measured very accurately with a calibration procedure based on the single-atom saturation curve of resonance fluorescence. In addition, the number of atoms in a trap could be controlled by suppressing stochastic loading events by means of a real-time active feedback on the magnetic-field gradient

Sognenavne, Albertslund Kommune (3 artikler). trap.dk

DEFF Research Database (Denmark)

Kællerød, Lars-Jakob Harding

2019-01-01

Artikler til Trap Danmarks netpublikation trap.dk Sognenavnene Herstedvester, Herstedøster og Opstandelseskirkens Sogn......Artikler til Trap Danmarks netpublikation trap.dk Sognenavnene Herstedvester, Herstedøster og Opstandelseskirkens Sogn...

Optical traps with geometric aberrations

International Nuclear Information System (INIS)

Roichman, Yael; Waldron, Alex; Gardel, Emily; Grier, David G.

2006-01-01

We assess the influence of geometric aberrations on the in-plane performance of optical traps by studying the dynamics of trapped colloidal spheres in deliberately distorted holographic optical tweezers. The lateral stiffness of the traps turns out to be insensitive to moderate amounts of coma, astigmatism, and spherical aberration. Moreover holographic aberration correction enables us to compensate inherent shortcomings in the optical train, thereby adaptively improving its performance. We also demonstrate the effects of geometric aberrations on the intensity profiles of optical vortices, whose readily measured deformations suggest a method for rapidly estimating and correcting geometric aberrations in holographic trapping systems

WATER-TRAPPED WORLDS

International Nuclear Information System (INIS)

Menou, Kristen

2013-01-01

Although tidally locked habitable planets orbiting nearby M-dwarf stars are among the best astronomical targets to search for extrasolar life, they may also be deficient in volatiles and water. Climate models for this class of planets show atmospheric transport of water from the dayside to the nightside, where it is precipitated as snow and trapped as ice. Since ice only slowly flows back to the dayside upon accumulation, the resulting hydrological cycle can trap a large amount of water in the form of nightside ice. Using ice sheet dynamical and thermodynamical constraints, I illustrate how planets with less than about a quarter the Earth's oceans could trap most of their surface water on the nightside. This would leave their dayside, where habitable conditions are met, potentially dry. The amount and distribution of residual liquid water on the dayside depend on a variety of geophysical factors, including the efficiency of rock weathering at regulating atmospheric CO 2 as dayside ocean basins dry up. Water-trapped worlds with dry daysides may offer similar advantages as land planets for habitability, by contrast with worlds where more abundant water freely flows around the globe

WATER-TRAPPED WORLDS

Energy Technology Data Exchange (ETDEWEB)

Menou, Kristen [Department of Astronomy, Columbia University, 550 West 120th Street, New York, NY 10027 (United States)

2013-09-01

Although tidally locked habitable planets orbiting nearby M-dwarf stars are among the best astronomical targets to search for extrasolar life, they may also be deficient in volatiles and water. Climate models for this class of planets show atmospheric transport of water from the dayside to the nightside, where it is precipitated as snow and trapped as ice. Since ice only slowly flows back to the dayside upon accumulation, the resulting hydrological cycle can trap a large amount of water in the form of nightside ice. Using ice sheet dynamical and thermodynamical constraints, I illustrate how planets with less than about a quarter the Earth's oceans could trap most of their surface water on the nightside. This would leave their dayside, where habitable conditions are met, potentially dry. The amount and distribution of residual liquid water on the dayside depend on a variety of geophysical factors, including the efficiency of rock weathering at regulating atmospheric CO{sub 2} as dayside ocean basins dry up. Water-trapped worlds with dry daysides may offer similar advantages as land planets for habitability, by contrast with worlds where more abundant water freely flows around the globe.

Spin resonance with trapped ions

Energy Technology Data Exchange (ETDEWEB)

Wunderlich, Ch; Balzer, Ch; Hannemann, T; Mintert, F; Neuhauser, W; Reiss, D; Toschek, P E [Institut fuer Laser-Physik, Universitaet Hamburg, Jungiusstrasse 9, 20355 Hamburg (Germany)

2003-03-14

A modified ion trap is described where experiments (in particular related to quantum information processing) that usually require optical radiation can be carried out using microwave or radio frequency electromagnetic fields. Instead of applying the usual methods for coherent manipulation of trapped ions, a string of ions in such a modified trap can be treated like a molecule in nuclear magnetic resonance experiments taking advantage of spin-spin coupling. The collection of trapped ions can be viewed as an N-qubit molecule with adjustable spin-spin coupling constants. Given N identically prepared quantum mechanical two-level systems (qubits), the optimal strategy to estimate their quantum state requires collective measurements. Using the ground state hyperfine levels of electrodynamically trapped {sup 171}Yb{sup +}, we have implemented an adaptive algorithm for state estimation involving sequential measurements on arbitrary qubit states.

Spin resonance with trapped ions

International Nuclear Information System (INIS)

Wunderlich, Ch; Balzer, Ch; Hannemann, T; Mintert, F; Neuhauser, W; Reiss, D; Toschek, P E

2003-01-01

A modified ion trap is described where experiments (in particular related to quantum information processing) that usually require optical radiation can be carried out using microwave or radio frequency electromagnetic fields. Instead of applying the usual methods for coherent manipulation of trapped ions, a string of ions in such a modified trap can be treated like a molecule in nuclear magnetic resonance experiments taking advantage of spin-spin coupling. The collection of trapped ions can be viewed as an N-qubit molecule with adjustable spin-spin coupling constants. Given N identically prepared quantum mechanical two-level systems (qubits), the optimal strategy to estimate their quantum state requires collective measurements. Using the ground state hyperfine levels of electrodynamically trapped 171 Yb + , we have implemented an adaptive algorithm for state estimation involving sequential measurements on arbitrary qubit states

Depositional features and stratigraphic sections in granitic plutons: implications for the emplacement and crystallization of granitic magma

Science.gov (United States)

Wiebe, R. A.; Collins, W. J.

1998-09-01

Many granitic plutons contain sheet-like masses of dioritic to gabbroic rocks or swarms of mafic to intermediate enclaves which represent the input of higher temperature, more mafic magma during crystallization of the granitic plutons. Small-scale structures associated with these bodies (e.g. load-cast and compaction features, silicic pipes extending from granitic layers into adjacent gabbroic sheets) indicate that the sheets and enclave swarms were deposited on a floor of the magma chamber (on granitic crystal mush and beneath crystal-poor magma) while the mafic magma was incompletely crystallized. These structures indicate 'way up', typically toward the interior of the intrusions, and appear to indicate that packages of mafic sheets and enclave concentrations in these plutons are a record of sequential deposition. Hence, these plutons preserve a stratigraphic history of events involved in the construction (filling, replenishment) and crystallization of the magma chamber. The distinctive features of these depositional portions of plutons allow them to be distinguished from sheeted intrusions, which usually preserve mutual intrusive contacts and 'dike-sill' relations of different magma types. The considerable thickness of material that can be interpreted as depositional, and the evidence for replenishment, suggest that magma chamber volumes at any one time were probably much less than the final size of the pluton. Thus, magma chambers may be constructed much more slowly than presently envisaged. The present steep attitudes of these structures in many plutons may have developed gradually as the floor of the chamber (along with the underlying solidified granite and country rock) sank during continuing episodes of magma chamber replenishment. These internal magmatic structures support recent suggestions that the room problem for granites could be largely accommodated by downward movement of country rock beneath the magma chamber.

The hidden traps in decision making.

Science.gov (United States)

Hammond, J S; Keeney, R L; Raiffa, H

1998-01-01

Bad decisions can often be traced back to the way the decisions were made--the alternatives were not clearly defined, the right information was not collected, the costs and benefits were not accurately weighted. But sometimes the fault lies not in the decision-making process but rather in the mind of the decision maker. The way the human brain works can sabotage the choices we make. John Hammond, Ralph Keeney, and Howard Raiffa examine eight psychological traps that are particularly likely to affect the way we make business decisions: The anchoring trap leads us to give disproportionate weight to the first information we receive. The statusquo trap biases us toward maintaining the current situation--even when better alternatives exist. The sunk-cost trap inclines us to perpetuate the mistakes of the past. The confirming-evidence trap leads us to seek out information supporting an existing predilection and to discount opposing information. The framing trap occurs when we misstate a problem, undermining the entire decision-making process. The overconfidence trap makes us overestimate the accuracy of our forecasts. The prudence trap leads us to be overcautious when we make estimates about uncertain events. And the recallability trap leads us to give undue weight to recent, dramatic events. The best way to avoid all the traps is awareness--forewarned is forearmed. But executives can also take other simple steps to protect themselves and their organizations from the various kinds of mental lapses. The authors show how to take action to ensure that important business decisions are sound and reliable.

Measurement and simulation of the pressure ratio between the two traps of double Penning trap mass spectrometers

International Nuclear Information System (INIS)

Neidherr, D.; Blaum, K.; Block, M.; Ferrer, R.; Herfurth, F.; Ketelaer, J.; Nagy, Sz.; Weber, C.

2008-01-01

Penning traps are ideal tools to perform high-precision mass measurements. For this purpose the cyclotron frequency of the stored charged particles is measured. In case of on-line mass measurements of short-lived nuclides produced at radioactive beam facilities the ions get in general first prepared and cooled by buffer-gas collisions in a preparation trap to reduce their motional amplitudes and are then transported to a precision trap for the cyclotron frequency determination. In modern Penning trap mass spectrometers both traps are placed in the homogeneous region of one superconducting magnet to optimize the transport efficiency. Because the gas pressure inside the precision trap has to be very low in order to minimize the damping of the ion motion caused by collisions with rest gas molecules during the frequency determination, a pumping barrier is installed between both traps. To predict the pressure difference between the two traps in the region of molecular gas flow the motion of each particle can be simulated without consideration of the other particles. Thus, it is possible to calculate the transit probability through a tube of a given geometry. The results are compared with experimentally obtained pressure differences.

WheelerLab: An interactive program for sequence stratigraphic analysis of seismic sections, outcrops and well sections and the generation of chronostratigraphic sections and dynamic chronostratigraphic sections

Science.gov (United States)

Amosu, Adewale; Sun, Yuefeng

WheelerLab is an interactive program that facilitates the interpretation of stratigraphic data (seismic sections, outcrop data and well sections) within a sequence stratigraphic framework and the subsequent transformation of the data into the chronostratigraphic domain. The transformation enables the identification of significant geological features, particularly erosional and non-depositional features that are not obvious in the original seismic domain. Although there are some software products that contain interactive environments for carrying out chronostratigraphic analysis, none of them are open-source codes. In addition to being open source, WheelerLab adds two important functionalities not present in currently available software: (1) WheelerLab generates a dynamic chronostratigraphic section and (2) WheelerLab enables chronostratigraphic analysis of older seismic data sets that exist only as images and not in the standard seismic file formats; it can also be used for the chronostratigraphic analysis of outcrop images and interpreted well sections. The dynamic chronostratigraphic section sequentially depicts the evolution of the chronostratigraphic chronosomes concurrently with the evolution of identified genetic stratal packages. This facilitates a better communication of the sequence-stratigraphic process. WheelerLab is designed to give the user both interactive and interpretational control over the transformation; this is most useful when determining the correct stratigraphic order for laterally separated genetic stratal packages. The program can also be used to generate synthetic sequence stratigraphic sections for chronostratigraphic analysis.

WheelerLab: An interactive program for sequence stratigraphic analysis of seismic sections, outcrops and well sections and the generation of chronostratigraphic sections and dynamic chronostratigraphic sections

Directory of Open Access Journals (Sweden)

Adewale Amosu

2017-01-01

Full Text Available WheelerLab is an interactive program that facilitates the interpretation of stratigraphic data (seismic sections, outcrop data and well sections within a sequence stratigraphic framework and the subsequent transformation of the data into the chronostratigraphic domain. The transformation enables the identification of significant geological features, particularly erosional and non-depositional features that are not obvious in the original seismic domain. Although there are some software products that contain interactive environments for carrying out chronostratigraphic analysis, none of them are open-source codes. In addition to being open source, WheelerLab adds two important functionalities not present in currently available software: (1 WheelerLab generates a dynamic chronostratigraphic section and (2 WheelerLab enables chronostratigraphic analysis of older seismic data sets that exist only as images and not in the standard seismic file formats; it can also be used for the chronostratigraphic analysis of outcrop images and interpreted well sections. The dynamic chronostratigraphic section sequentially depicts the evolution of the chronostratigraphic chronosomes concurrently with the evolution of identified genetic stratal packages. This facilitates a better communication of the sequence-stratigraphic process. WheelerLab is designed to give the user both interactive and interpretational control over the transformation; this is most useful when determining the correct stratigraphic order for laterally separated genetic stratal packages. The program can also be used to generate synthetic sequence stratigraphic sections for chronostratigraphic analysis.

Microfabricated Waveguide Atom Traps.

Energy Technology Data Exchange (ETDEWEB)

Jau, Yuan-Yu [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2017-09-01

A nanoscale , microfabricated waveguide structure can in - principle be used to trap atoms in well - defined locations and enable strong photon-atom interactions . A neutral - atom platform based on this microfabrication technology will be prealigned , which is especially important for quantum - control applications. At present, there is still no reported demonstration of evanescent - field atom trapping using a microfabricated waveguide structure. We described the capabilities established by our team for future development of the waveguide atom - trapping technology at SNL and report our studies to overcome the technical challenges of loading cold atoms into the waveguide atom traps, efficient and broadband optical coupling to a waveguide, and the waveguide material for high - power optical transmission. From the atomic - physics and the waveguide modeling, w e have shown that a square nano-waveguide can be utilized t o achieve better atomic spin squeezing than using a nanofiber for first time.

Laser-cooling and electromagnetic trapping of neutral atoms

International Nuclear Information System (INIS)

Phillips, W.D.; Migdall, A.L.; Metcalf, H.J.

1986-01-01

Until recently it has been impossible to confine and trap neutral atoms using electromagnetic fields. While many proposals for such traps exist, the small potential energy depth of the traps and the high kinetic energy of available atoms prevented trapping. We review various schemes for atom trapping, the advances in laser cooling of atomic beams which have now made trapping possible, and the successful magnetic trapping of cold sodium atoms

The necessity and application of stratigraphic borings in hydrogeologic site assessments

International Nuclear Information System (INIS)

Sciacca, J.

1991-01-01

The siting and placement of monitoring wells is one of the most critical elements in hydrogeologic assessments of contaminated sites. Monitoring wells are placed to collect hydraulic and chemical concentration data to: (1) determine potential groundwater flow paths and rates: (2) analyze the nature and extent of chemical constituents in groundwater; and (3) estimate contaminant fate and transport. In many instances monitoring wells provide inappropriate or erroneous hydraulic data, do not provide coverage of potential high permeability flow pathways (such as channel sands) or may themselves create (through improper construction) a vertical conduit for contaminant flow from low permeability to high permeability units. This problem is commonly due to installing monitoring wells before conducting essential stratigraphic analysis and formulating a depositional model for the site area. This paper presents case examples where stratigraphic borings were drilled and logged in the vicinity of proposed well locations to effectively design and install the monitoring well network. The borings were continuously sampled or geophysically logged to provide a vertical profile of the borehole. In addition, the geophysical logs provided curve signatures which allowed interpretation of depositional facies. These data were used to interpret subsurface stratigraphy and effectively position monitoring wells that achieve the above objectives and prevent problems associated with faulty well positioning. This method may cost more initially. However, these initial costs are cheaper than long-term project expenses for abandoning improperly completed wells. subsequently installing supplemental monitoring wells or modifying poorly designed treatment systems which resulted from improper or insufficient data generated from the initial monitoring network

Optical Trapping of Ion Coulomb Crystals

Science.gov (United States)

Schmidt, Julian; Lambrecht, Alexander; Weckesser, Pascal; Debatin, Markus; Karpa, Leon; Schaetz, Tobias

2018-04-01

The electronic and motional degrees of freedom of trapped ions can be controlled and coherently coupled on the level of individual quanta. Assembling complex quantum systems ion by ion while keeping this unique level of control remains a challenging task. For many applications, linear chains of ions in conventional traps are ideally suited to address this problem. However, driven motion due to the magnetic or radio-frequency electric trapping fields sometimes limits the performance in one dimension and severely affects the extension to higher-dimensional systems. Here, we report on the trapping of multiple barium ions in a single-beam optical dipole trap without radio-frequency or additional magnetic fields. We study the persistence of order in ensembles of up to six ions within the optical trap, measure their temperature, and conclude that the ions form a linear chain, commonly called a one-dimensional Coulomb crystal. As a proof-of-concept demonstration, we access the collective motion and perform spectrometry of the normal modes in the optical trap. Our system provides a platform that is free of driven motion and combines advantages of optical trapping, such as state-dependent confinement and nanoscale potentials, with the desirable properties of crystals of trapped ions, such as long-range interactions featuring collective motion. Starting with small numbers of ions, it has been proposed that these properties would allow the experimental study of many-body physics and the onset of structural quantum phase transitions between one- and two-dimensional crystals.

Ball-grid array architecture for microfabricated ion traps

Science.gov (United States)

Guise, Nicholas D.; Fallek, Spencer D.; Stevens, Kelly E.; Brown, K. R.; Volin, Curtis; Harter, Alexa W.; Amini, Jason M.; Higashi, Robert E.; Lu, Son Thai; Chanhvongsak, Helen M.; Nguyen, Thi A.; Marcus, Matthew S.; Ohnstein, Thomas R.; Youngner, Daniel W.

2015-05-01

State-of-the-art microfabricated ion traps for quantum information research are approaching nearly one hundred control electrodes. We report here on the development and testing of a new architecture for microfabricated ion traps, built around ball-grid array (BGA) connections, that is suitable for increasingly complex trap designs. In the BGA trap, through-substrate vias bring electrical signals from the back side of the trap die to the surface trap structure on the top side. Gold-ball bump bonds connect the back side of the trap die to an interposer for signal routing from the carrier. Trench capacitors fabricated into the trap die replace area-intensive surface or edge capacitors. Wirebonds in the BGA architecture are moved to the interposer. These last two features allow the trap die to be reduced to only the area required to produce trapping fields. The smaller trap dimensions allow tight focusing of an addressing laser beam for fast single-qubit rotations. Performance of the BGA trap as characterized with 40Ca+ ions is comparable to previous surface-electrode traps in terms of ion heating rate, mode frequency stability, and storage lifetime. We demonstrate two-qubit entanglement operations with 171Yb+ ions in a second BGA trap.

Ball-grid array architecture for microfabricated ion traps

International Nuclear Information System (INIS)

Guise, Nicholas D.; Fallek, Spencer D.; Stevens, Kelly E.; Brown, K. R.; Volin, Curtis; Harter, Alexa W.; Amini, Jason M.; Higashi, Robert E.; Lu, Son Thai; Chanhvongsak, Helen M.; Nguyen, Thi A.; Marcus, Matthew S.; Ohnstein, Thomas R.; Youngner, Daniel W.

2015-01-01

State-of-the-art microfabricated ion traps for quantum information research are approaching nearly one hundred control electrodes. We report here on the development and testing of a new architecture for microfabricated ion traps, built around ball-grid array (BGA) connections, that is suitable for increasingly complex trap designs. In the BGA trap, through-substrate vias bring electrical signals from the back side of the trap die to the surface trap structure on the top side. Gold-ball bump bonds connect the back side of the trap die to an interposer for signal routing from the carrier. Trench capacitors fabricated into the trap die replace area-intensive surface or edge capacitors. Wirebonds in the BGA architecture are moved to the interposer. These last two features allow the trap die to be reduced to only the area required to produce trapping fields. The smaller trap dimensions allow tight focusing of an addressing laser beam for fast single-qubit rotations. Performance of the BGA trap as characterized with 40 Ca + ions is comparable to previous surface-electrode traps in terms of ion heating rate, mode frequency stability, and storage lifetime. We demonstrate two-qubit entanglement operations with 171 Yb + ions in a second BGA trap

Liquid metal cold trap

International Nuclear Information System (INIS)

Hundal, R.

1976-01-01

A cold trap assembly for removing impurities from a liquid metal is described. A hole between the incoming impure liquid metal and purified outgoing liquid metal acts as a continuous bleed means and thus prevents the accumulation of cover gases within the cold trap assembly

Precision mass measurements at THe-trap and the FSU trap

Energy Technology Data Exchange (ETDEWEB)

Hoecker, Martin Juergen

2016-07-26

THe-Trap is a Penning-trap mass spectrometer at the Max-Planck-Institute for Nuclear Physics in Heidelberg, Germany, that aims to measure the T/{sup 3}He mass ratio with a relative uncertainty of 10{sup -11}. Improvements of the measurement technique, in particular the measurement of systematic shifts, enabled measurements of mass ratios with relative uncertainties of 7.10{sup -11}, as demonstrated by a cyclotron frequency ratio determination on {sup 12}C{sup 4+}/{sup 16}O{sup 5+}. This uncertainty was limited by the lineshape. An improved theoretical model based on a rotating wave approximation can be used to describe dynamical interactions between the detection system and the ion, in order to better understand the lineshape and to further reduce the uncertainty. The Florida State University trap is a Penning-trap mass spectrometer located in Tallahassee, Florida (USA). In the context of this thesis, three mass ratios were measured, and further 20 mass ratio measurements analyzed, which resulted in the publication of the masses of {sup 82,83}Kr, {sup 131,134}Xe, {sup 86-88}Sr, and {sup 170-174,176}Yb with relative uncertainties between (0.9 - 1.3).10{sup -10}. These masses serve as reference masses for other experiments and have applications in the determination of the fine-structure constant alpha via the photon-recoil method.

Modelling and comparison of trapped fields in (RE)BCO bulk superconductors for activation using pulsed field magnetization

Science.gov (United States)

Ainslie, M. D.; Fujishiro, H.; Ujiie, T.; Zou, J.; Dennis, A. R.; Shi, Y.-H.; Cardwell, D. A.

2014-06-01

The ability to generate a permanent, stable magnetic field unsupported by an electromotive force is fundamental to a variety of engineering applications. Bulk high temperature superconducting (HTS) materials can trap magnetic fields of magnitude over ten times higher than the maximum field produced by conventional magnets, which is limited practically to rather less than 2 T. In this paper, two large c-axis oriented, single-grain YBCO and GdBCO bulk superconductors are magnetized by the pulsed field magnetization (PFM) technique at temperatures of 40 and 65 K and the characteristics of the resulting trapped field profile are investigated with a view of magnetizing such samples as trapped field magnets (TFMs) in situ inside a trapped flux-type superconducting electric machine. A comparison is made between the temperatures at which the pulsed magnetic field is applied and the results have strong implications for the optimum operating temperature for TFMs in trapped flux-type superconducting electric machines. The effects of inhomogeneities, which occur during the growth process of single-grain bulk superconductors, on the trapped field and maximum temperature rise in the sample are modelled numerically using a 3D finite-element model based on the H-formulation and implemented in Comsol Multiphysics 4.3a. The results agree qualitatively with the observed experimental results, in that inhomogeneities act to distort the trapped field profile and reduce the magnitude of the trapped field due to localized heating within the sample and preferential movement and pinning of flux lines around the growth section regions (GSRs) and growth sector boundaries (GSBs), respectively. The modelling framework will allow further investigation of various inhomogeneities that arise during the processing of (RE)BCO bulk superconductors, including inhomogeneous Jc distributions and the presence of current-limiting grain boundaries and cracks, and it can be used to assist optimization of

Fine reservoir structure modeling based upon 3D visualized stratigraphic correlation between horizontal wells: methodology and its application

Science.gov (United States)

Chenghua, Ou; Chaochun, Li; Siyuan, Huang; Sheng, James J.; Yuan, Xu

2017-12-01

As the platform-based horizontal well production mode has been widely applied in petroleum industry, building a reliable fine reservoir structure model by using horizontal well stratigraphic correlation has become very important. Horizontal wells usually extend between the upper and bottom boundaries of the target formation, with limited penetration points. Using these limited penetration points to conduct well deviation correction means the formation depth information obtained is not accurate, which makes it hard to build a fine structure model. In order to solve this problem, a method of fine reservoir structure modeling, based on 3D visualized stratigraphic correlation among horizontal wells, is proposed. This method can increase the accuracy when estimating the depth of the penetration points, and can also effectively predict the top and bottom interfaces in the horizontal penetrating section. Moreover, this method will greatly increase not only the number of points of depth data available, but also the accuracy of these data, which achieves the goal of building a reliable fine reservoir structure model by using the stratigraphic correlation among horizontal wells. Using this method, four 3D fine structure layer models have been successfully built of a specimen shale gas field with platform-based horizontal well production mode. The shale gas field is located to the east of Sichuan Basin, China; the successful application of the method has proven its feasibility and reliability.

The role of sediment supply in large-scale stratigraphic architecture of ancient Gilbert-type deltas (Pliocene Siena-Radicofani Basin, Italy)

Science.gov (United States)

Martini, Ivan; Ambrosetti, Elisa; Sandrelli, Fabio

2017-04-01

Aggradation, progradation and retrogradation are the main patterns that define the large-scale architecture of Gilbert-type deltas. These patterns are governed by the ratio between the variation in accommodation space and sediment supply experienced during delta growth. Sediment supply variations are difficult to estimate in ancient settings; hence, it is rarely possible to assess its significance in the large-scale stratigraphic architecture of Gilbert-type deltas. This paper presents a stratigraphic analysis of a Pliocene deltaic complex composed of two coeval and narrowly spaced deltaic branches. The two branches recorded the same tectonic- and climate-induced accommodation space variations. As a result, this deltaic complex represents a natural laboratory for testing the effects of sediment supply variations on the stratigraphic architecture of Gilbert-type deltas. The field data suggest that a sediment supply which is able to counteract the accommodation generated over time promotes the aggradational/progradational attitude of Gilbert-type deltas, as well as the development of thick foreset deposits. By contrast, if the sediment supply is not sufficient for counterbalancing the generated accommodation, an aggradational/retrogradational stratigraphic architecture is promoted. In this case, the deltaic system is forced to withdraw during the different phases of generation of accommodation, with the subsequent flooding of previously deposited sub-horizontal topset deposits (i.e., the delta plain). The subsequent deltaic progradation occurs above these deposits and, consequently, the available space for foresets growth is limited to the water depth between the base-level and the older delta plain. This leads to the vertical stacking of relatively thin deltaic deposits with an overall aggradatational/retrogradational attitude.

Electron trapping during irradiation in reoxidized nitrided oxide

International Nuclear Information System (INIS)

Mallik, A.; Vasi, J.; Chandorkar, A.N.

1993-01-01

Isochronal detrapping experiments have been performed following irradiation under different gate biases in reoxidized nitrided oxide (RNO) MOS capacitors. These show electron trapping by the nitridation-induced electron traps at low oxide fields during irradiation. A difference in the detrapping behavior of trapped holes and electrons is observed, with trapped holes being detrapped at relatively lower temperatures compared to trapped electrons. Electron trapping shows a strong dependence on tile magnitude of the applied gate bias during irradiation but is independent of its polarity. Conventional oxide devices, as expected, do not show any electron trapping during irradiation by the native electron traps. Finally, a comparison of the isochronal detrapping behavior following irradiation and following avalanche injection of electrons has been made to estimate the extent of electron trapping. The results show that electron trapping by the nitridation-induced electron traps does not play the dominant role in improving radiation performance of RNO, though its contribution cannot be completely neglected for low oxide field irradiations

Trapping Triatominae in Silvatic Habitats

Directory of Open Access Journals (Sweden)

Noireau François

2002-01-01

Full Text Available Large-scale trials of a trapping system designed to collect silvatic Triatominae are reported. Live-baited adhesive traps were tested in various ecosystems and different triatomine habitats (arboreal and terrestrial. The trials were always successful, with a rate of positive habitats generally over 20% and reaching 48.4% for palm trees of the Amazon basin. Eleven species of Triatominae belonging to the three genera of public health importance (Triatoma, Rhodnius and Panstrongylus were captured. This trapping system provides an effective way to detect the presence of triatomines in terrestrial and arboreal silvatic habitats and represents a promising tool for ecological studies. Various lines of research are contemplated to improve the performance of this trapping system.

Optical Trapping of Ion Coulomb Crystals

Directory of Open Access Journals (Sweden)

Julian Schmidt

2018-05-01

Full Text Available The electronic and motional degrees of freedom of trapped ions can be controlled and coherently coupled on the level of individual quanta. Assembling complex quantum systems ion by ion while keeping this unique level of control remains a challenging task. For many applications, linear chains of ions in conventional traps are ideally suited to address this problem. However, driven motion due to the magnetic or radio-frequency electric trapping fields sometimes limits the performance in one dimension and severely affects the extension to higher-dimensional systems. Here, we report on the trapping of multiple barium ions in a single-beam optical dipole trap without radio-frequency or additional magnetic fields. We study the persistence of order in ensembles of up to six ions within the optical trap, measure their temperature, and conclude that the ions form a linear chain, commonly called a one-dimensional Coulomb crystal. As a proof-of-concept demonstration, we access the collective motion and perform spectrometry of the normal modes in the optical trap. Our system provides a platform that is free of driven motion and combines advantages of optical trapping, such as state-dependent confinement and nanoscale potentials, with the desirable properties of crystals of trapped ions, such as long-range interactions featuring collective motion. Starting with small numbers of ions, it has been proposed that these properties would allow the experimental study of many-body physics and the onset of structural quantum phase transitions between one- and two-dimensional crystals.

Performance improvement of charge trap flash memory by using a composition-modulated high-k trapping layer

International Nuclear Information System (INIS)

Tang Zhen-Jie; Li Rong; Yin Jiang

2013-01-01

A composition-modulated (HfO 2 ) x (Al 2 O3) 1−x charge trapping layer is proposed for charge trap flash memory by controlling the Al atom content to form a peak and valley shaped band gap. It is found that the memory device using the composition-modulated (HfO 2 ) x (Al 2 O 3 ) 1−x as the charge trapping layer exhibits a larger memory window of 11.5 V, improves data retention even at high temperature, and enhances the program/erase speed. Improvements of the memory characteristics are attributed to the special band-gap structure resulting from the composition-modulated trapping layer. Therefore, the composition-modulated charge trapping layer may be useful in future nonvolatile flash memory device application. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

Science, conservation, and camera traps

Science.gov (United States)

Nichols, James D.; Karanth, K. Ullas; O'Connel, Allan F.; O'Connell, Allan F.; Nichols, James D.; Karanth, K. Ullas

2011-01-01

Biologists commonly perceive camera traps as a new tool that enables them to enter the hitherto secret world of wild animals. Camera traps are being used in a wide range of studies dealing with animal ecology, behavior, and conservation. Our intention in this volume is not to simply present the various uses of camera traps, but to focus on their use in the conduct of science and conservation. In this chapter, we provide an overview of these two broad classes of endeavor and sketch the manner in which camera traps are likely to be able to contribute to them. Our main point here is that neither photographs of individual animals, nor detection history data, nor parameter estimates generated from detection histories are the ultimate objective of a camera trap study directed at either science or management. Instead, the ultimate objectives are best viewed as either gaining an understanding of how ecological systems work (science) or trying to make wise decisions that move systems from less desirable to more desirable states (conservation, management). Therefore, we briefly describe here basic approaches to science and management, emphasizing the role of field data and associated analyses in these processes. We provide examples of ways in which camera trap data can inform science and management.

The Electronic McPhail Trap

Science.gov (United States)

Potamitis, Ilyas; Rigakis, Iraklis; Fysarakis, Konstantinos

2014-01-01

Certain insects affect cultivations in a detrimental way. A notable case is the olive fruit fly (Bactrocera oleae (Rossi)), that in Europe alone causes billions of euros in crop-loss/per year. Pests can be controlled with aerial and ground bait pesticide sprays, the efficiency of which depends on knowing the time and location of insect infestations as early as possible. The inspection of traps is currently carried out manually. Automatic monitoring traps can enhance efficient monitoring of flying pests by identifying and counting targeted pests as they enter the trap. This work deals with the hardware setup of an insect trap with an embedded optoelectronic sensor that automatically records insects as they fly in the trap. The sensor responsible for detecting the insect is an array of phototransistors receiving light from an infrared LED. The wing-beat recording is based on the interruption of the emitted light due to the partial occlusion from insect's wings as they fly in the trap. We show that the recordings are of high quality paving the way for automatic recognition and transmission of insect detections from the field to a smartphone. This work emphasizes the hardware implementation of the sensor and the detection/counting module giving all necessary implementation details needed to construct it. PMID:25429412

Cavity sideband cooling of trapped molecules

NARCIS (Netherlands)

Kowalewski, Markus; Morigi, Giovanna; Pinkse, Pepijn Willemszoon Harry; de Vivie-Riedle, Regina

2011-01-01

The efficiency of cavity sideband cooling of trapped molecules is theoretically investigated for the case in which the infrared transition between two rovibrational states is used as a cycling transition. The molecules are assumed to be trapped either by a radiofrequency or optical trapping

Single-molecule dynamics in nanofabricated traps

Science.gov (United States)

Cohen, Adam

2009-03-01

The Anti-Brownian Electrokinetic trap (ABEL trap) provides a means to immobilize a single fluorescent molecule in solution, without surface attachment chemistry. The ABEL trap works by tracking the Brownian motion of a single molecule, and applying feedback electric fields to induce an electrokinetic motion that approximately cancels the Brownian motion. We present a new design for the ABEL trap that allows smaller molecules to be trapped and more information to be extracted from the dynamics of a single molecule than was previously possible. In particular, we present strategies for extracting dynamically fluctuating mobilities and diffusion coefficients, as a means to probe dynamic changes in molecular charge and shape. If one trapped molecule is good, many trapped molecules are better. An array of single molecules in solution, each immobilized without surface attachment chemistry, provides an ideal test-bed for single-molecule analyses of intramolecular dynamics and intermolecular interactions. We present a technology for creating such an array, using a fused silica plate with nanofabricated dimples and a removable cover for sealing single molecules within the dimples. With this device one can watch the shape fluctuations of single molecules of DNA or study cooperative interactions in weakly associating protein complexes.

Physics with Trapped Antihydrogen

Science.gov (United States)

Charlton, Michael

2017-04-01

For more than a decade antihydrogen atoms have been formed by mixing antiprotons and positrons held in arrangements of charged particle (Penning) traps. More recently, magnetic minimum neutral atom traps have been superimposed upon the anti-atom production region, promoting the trapping of a small quantity of the antihydrogen yield. We will review these advances, and describe some of the first physics experiments performed on anrtihydrogen including the observation of the two-photon 1S-2S transition, invesigation of the charge neutrailty of the anti-atom and studies of the ground state hyperfine splitting. We will discuss the physics motivations for undertaking these experiments and describe some near-future initiatives.

Ion traps fabricated in a CMOS foundry

Energy Technology Data Exchange (ETDEWEB)

Mehta, K. K.; Ram, R. J. [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Eltony, A. M.; Chuang, I. L. [Center for Ultracold Atoms, Research Laboratory of Electronics and Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Bruzewicz, C. D.; Sage, J. M., E-mail: jsage@ll.mit.edu; Chiaverini, J., E-mail: john.chiaverini@ll.mit.edu [Lincoln Laboratory, Massachusetts Institute of Technology, Lexington, Massachusetts 02420 (United States)

2014-07-28

We demonstrate trapping in a surface-electrode ion trap fabricated in a 90-nm CMOS (complementary metal-oxide-semiconductor) foundry process utilizing the top metal layer of the process for the trap electrodes. The process includes doped active regions and metal interconnect layers, allowing for co-fabrication of standard CMOS circuitry as well as devices for optical control and measurement. With one of the interconnect layers defining a ground plane between the trap electrode layer and the p-type doped silicon substrate, ion loading is robust and trapping is stable. We measure a motional heating rate comparable to those seen in surface-electrode traps of similar size. This demonstration of scalable quantum computing hardware utilizing a commercial CMOS process opens the door to integration and co-fabrication of electronics and photonics for large-scale quantum processing in trapped-ion arrays.

High Optical Access Trap 2.0.

Energy Technology Data Exchange (ETDEWEB)

Maunz, Peter Lukas Wilhelm [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2016-01-26

The High Optical Access (HOA) trap was designed in collaboration with the Modular Universal Scalable Ion-trap Quantum Computer (MUSIQC) team, funded along with Sandia National Laboratories through IARPA's Multi Qubit Coherent Operations (MQCO) program. The design of version 1 of the HOA trap was completed in September 2012 and initial devices were completed and packaged in February 2013. The second version of the High Optical Access Trap (HOA-2) was completed in September 2014 and is available at IARPA's disposal.

Laser trapping of 21Na atoms

International Nuclear Information System (INIS)

Lu, Zheng-Tian.

1994-09-01

This thesis describes an experiment in which about four thousand radioactive 21 Na (t l/2 = 22 sec) atoms were trapped in a magneto-optical trap with laser beams. Trapped 21 Na atoms can be used as a beta source in a precision measurement of the beta-asymmetry parameter of the decay of 21 Na → 21 Ne + Β + + v e , which is a promising way to search for an anomalous right-handed current coupling in charged weak interactions. Although the number o trapped atoms that we have achieved is still about two orders of magnitude lower than what is needed to conduct a measurement of the beta-asymmetry parameter at 1% of precision level, the result of this experiment proved the feasibility of trapping short-lived radioactive atoms. In this experiment, 21 Na atoms were produced by bombarding 24 Mg with protons of 25 MeV at the 88 in. Cyclotron of Lawrence Berkeley Laboratory. A few recently developed techniques of laser manipulation of neutral atoms were applied in this experiment. The 21 Na atoms emerging from a heated oven were first transversely cooled. As a result, the on-axis atomic beam intensity was increased by a factor of 16. The atoms in the beam were then slowed down from thermal speed by applying Zeeman-tuned slowing technique, and subsequently loaded into a magneto-optical trap at the end of the slowing path. The last two chapters of this thesis present two studies on the magneto-optical trap of sodium atoms. In particular, the mechanisms of magneto-optical traps at various laser frequencies and the collisional loss mechanisms of these traps were examined

The stratigraphic distribution of large marine vertebrates and shell beds in the Pliocene of Tuscany

Science.gov (United States)

Dominici, Stefano; Benvenuti, Marco; Danise, Silvia

2015-04-01

The record of 337 shark fossils, 142 cetaceans and 10 sea cows from the Pliocene of Tuscany, mostly from historical museum collections, is revised. The majority of these fossils are concentrated at a few geographic sites from separated hinterland basins, on the South-Western side of the Northern Apennines. To better understand the meaning of these concentrations, the sequence stratigraphic distribution of more recent findings of large marine vertebrates is reconstructed against a high-resolution framework based on sedimentary facies analysis. These remains are usually covered by, or included in mudstones deposited far from the coast (N=12), skeletons being usually articulated, slightly displaced, and often bioeroded. A minor part of better preserved articulated skeletons is associated with sandstones from deltaic paleonenvironments (N=2). Marine mammal and shark remains may be associated with laterally-continuous shell accumulations, a type of concentration occurring at maximum flooding surfaces, separating relatively coarse-grained facies from open marine mudstones. Shell beds were bulk-sampled at 66 locations from six basins, covering a wide range of sedimentary facies, and spanning a chronologic interval of about 2.5 million years. A dataset of 62,655 mollusc specimens belonging to 496 species formed the basis of a statistical study to reconstruct the structure of the benthic communities, and to estimate paleodepths from intertidal to upper bathyal settings. Mollusc associations closely mirror the distribution of sedimentary facies, allowing for a fine tuning of the sequence stratigraphic architecture. Merging paleogeographic, stratigraphic and paleoecologic data, we conclude that the more abundant and diverse accumulations of large vertebrates took place in settings under the influence of coastal upwelling. A modern analogue occurs today in the Ligurian Sea, on the Tuscan offshore, where abundant nutrients carried by deep-marine currents of Western origin

Vertical and lateral flux on the continental slope off Pakistan: correlation of sediment core and trap results

Science.gov (United States)

Schulz, H.; von Rad, U.

2014-06-01

Due to the lack of bioturbation, the varve-laminated muds from the oxygen minimum zone (OMZ) off Pakistan provide a unique opportunity to precisely determine the vertical and lateral sediment fluxes in the nearshore part of the northeastern Arabian Sea. West of Karachi (Hab area), the results of two sediment trap stations (EPT and WPT) were correlated with 16 short sediment cores on a depth transect crossing the OMZ. The top of a distinct, either reddish- or light-gray silt layer, 210Pb-dated as AD 1905 ± 10, was used as an isochronous stratigraphic marker bed to calculate sediment accumulation rates. In one core, the red and gray layer were separated by a few (5-10) thin laminae. According to our varve model, this contributes water column above. All traps on the steep Makran continental slope show exceptionally high, pulsed winter fluxes of up to 5000 mg m-2 d-1. Based on core results, the flux at the seafloor amounts to 4000 mg m-2 d-1 and agrees remarkably well with the bulk winter flux of material, as well as with the flux of the individual bulk components of organic carbon, calcium carbonate and opal. However, due to the extreme mass of remobilized matter, the high winter flux events exceeded the capacity of the shallow traps. Based on our comparisons, we argue that high-flux events must occur regularly during winter within the upper OMZ off Pakistan to explain the high accumulations rates. These show distribution patterns that are a negative function of water depth and distance from the shelf. Some of the sediment fractions show marked shifts in accumulation rates near the lower boundary of the OMZ. For instance, the flux of benthic foraminifera is lowered but stable below ~1200-1300 m. However, flux and sedimentation in the upper eastern Makran area are dominated by the large amount of laterally advected fine-grained material and by the pulsed nature of the resuspension events at the upper margin during winter.

Calibration of optically trapped nanotools

Energy Technology Data Exchange (ETDEWEB)

Carberry, D M; Simpson, S H; Grieve, J A; Hanna, S; Miles, M J [H H Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Wang, Y; Schaefer, H; Steinhart, M [Institute for Chemistry, University of Osnabrueck, Osnabrueck (Germany); Bowman, R; Gibson, G M; Padgett, M J, E-mail: m.j.miles@bristol.ac.uk [SUPA, Department of Physics and Astronomy, University of Glasgow, Science Road, Glasgow G12 8QQ (United Kingdom)

2010-04-30

Holographically trapped nanotools can be used in a novel form of force microscopy. By measuring the displacement of the tool in the optical traps, the contact force experienced by the probe can be inferred. In the following paper we experimentally demonstrate the calibration of such a device and show that its behaviour is independent of small changes in the relative position of the optical traps. Furthermore, we explore more general aspects of the thermal motion of the tool.

Diffusion to finite-size traps

International Nuclear Information System (INIS)

Richards, P.M.

1986-01-01

The survival probability of a random-walking particle is derived for hopping in a random distribution of traps of arbitrary radius and concentration. The single-center approximation is shown to be valid for times of physical interest even when the fraction of volume occupied by traps approaches unity. The theory is based on computation of the number of different potential trap regions sampled in a random walk and is confirmed by simulations on a simple-cubic lattice

RNA-Seq reveals the molecular mechanism of trapping and killing of root-knot nematodes by nematode-trapping fungi.

Science.gov (United States)

Pandit, Ramesh; Patel, Reena; Patel, Namrata; Bhatt, Vaibhav; Joshi, Chaitanya; Singh, Pawan Kumar; Kunjadia, Anju

2017-04-01

Nematode-trapping fungi are well known for their inherent potential to trap and kill nematodes using specialized trapping devices. However, the molecular mechanisms underlying the trapping and subsequent processes are still unclear. Therefore, in this study, we examined differential genes expression in two nematode-trapping fungi after baiting with nematode extracts. In Arthrobotrys conoides, 809 transcripts associated with diverse functions such as signal transduction, morphogenesis, stress response and peroxisomal proteins, proteases, chitinases and genes involved in the host-pathogen interaction showed differential expression with fold change (>±1.5 fold) in the presence of nematode extract with FDR (p-value nematode-trapping fungi for its host. The findings illustrate the molecular mechanism of fungal parasitism in A. conoides which may be helpful in developing a potential biocontrol agent against parasitic nematodes.

Chemical changes of minerals trapped in the lichen Trapelia involuta. Implication for lichen effect on mobility of uranium and toxic metals

International Nuclear Information System (INIS)

Kasama, Takeshi; Murakami, Takashi; Ohnuki, Toshihiko

2002-01-01

To elucidate development of minerals trapped in a lichen, we examined the lichen Trapelia involuta growing directly on secondary uranyl minerals and U-enriched Fe oxide and hydroxide minerals. Sericite and other minerals in the underlying rock are trapped in the lichen T. involuta during its biological growth and chemically changed by lichen activities. The presence of chemically changed sericite accompanied by an Fe-bearing mineral in the lichen suggests that dissolution of sericite is promoted mainly by polysaccharides excreted by the lichen. Oxalic acid or lichen acids absent in the medulla may not play an important role in the dissolution. Our results suggest that lichens on metal-rich surface affect the mobility of uranium and other toxic metals through dissolution followed by trap of minerals from the underlying rock. (author)

Stratigraphic Stacking of Deepmarine Channel Levee Turbidites: Scales of Cyclicity and their Origin. Examples from the Laingsburg Fm. (Karoo, South Africa) and the Rosario Fm. (Baja, Mexico)

Science.gov (United States)

Kane, I. A.; Hodgson, D.

2009-12-01

Thinning upwards of the turbidite beds that form deepmarine channel levees is a common motif reported from modern and recent levees on the seafloor, from subsurface examples, and from outcropping ancient examples. Because levees are thought to be built by deposition from turbidity currents superelevated over their channel form, the volume and style of overbank deposition are controlled primarily by the relationship between levee height (i.e., thalweg to crest) and flow thickness, determining the amount of overspill. Thus stratigraphic variability of turbidite thickness is explained by some change in either or both of those factors, which may arise autocyclicly or allocyclicly. Variation in the ratio of intra-channel and extra-channel deposition can be an autocyclic stratigraphic response, e.g., in bypass dominated systems, thalweg aggradation may be retarded with respect to levee aggradation, hence as levee relief increases, flows become more confined and, given a relatively narrow range of flow sizes, the volume of overbank flow and deposit thickness decrease with stratigraphic height. However, the same stratigraphic response of the levee may occur due to allocyclic flow magnitude variation, i.e., through decreasing flow magnitude. In both the autocyclic and allocyclic case the stratigraphic response of the levee may be one of thinning upwards, even if the overall system response may be one of progradation (autocyclic bypassing case) or retrogradation (allocyclic decreasing flow magnitude case), with entirely different connotations for sequence stratigraphic interpretation. Here we report examples of different scales of bed thickness cyclicity (both thickening and thinning upward cycles superimposed by smaller scale cycles) within levees of the Rosario Formation, Baja California, Mexico, and from the Laingsburg Formation, Karoo, South Africa, and, together with published examples, discuss criteria for the recognition, and drivers of, autocyclic and allocyclic bed

The Electronic McPhail Trap

Directory of Open Access Journals (Sweden)

Ilyas Potamitis

2014-11-01

Full Text Available Certain insects affect cultivations in a detrimental way. A notable case is the olive fruit fly (Bactrocera oleae (Rossi, that in Europe alone causes billions of euros in crop-loss/per year. Pests can be controlled with aerial and ground bait pesticide sprays, the efficiency of which depends on knowing the time and location of insect infestations as early as possible. The inspection of traps is currently carried out manually. Automatic monitoring traps can enhance efficient monitoring of flying pests by identifying and counting targeted pests as they enter the trap. This work deals with the hardware setup of an insect trap with an embedded optoelectronic sensor that automatically records insects as they fly in the trap. The sensor responsible for detecting the insect is an array of phototransistors receiving light from an infrared LED. The wing-beat recording is based on the interruption of the emitted light due to the partial occlusion from insect’s wings as they fly in the trap. We show that the recordings are of high quality paving the way for automatic recognition and transmission of insect detections from the field to a smartphone. This work emphasizes the hardware implementation of the sensor and the detection/counting module giving all necessary implementation details needed to construct it.

Laser trapping of radioactive francium atoms

International Nuclear Information System (INIS)

Sprouse, G.D.; Orozco, L.A.; Simsarian, J.E.; Shi, W.; Zhao, W.Z.

1997-01-01

The difficult problem of quickly slowing and cooling nuclear reaction products so that they can be injected into a laser trap has been solved by several groups and there are now strong efforts to work with the trapped atoms. The atoms are confined in the trap to a small spatial volume of the order of 1 mm 3 , but more importantly, they are also confined in velocity, which makes them an ideal sample for spectroscopic measurements with other lasers. We have recently trapped radioactive francium and have embarked on a program to further study the francium atom as a prelude to a test of the Standard Model analogous to previous work with Cs. Our sample of 3 min 210 Fr now contains over 20 000 atoms, and is readily visible with an ordinary TV camera. We work on-line with the accelerator, and continuously load the trap to replace losses due to decay and collisions with background gas. We have maintained a sample of Fr atoms in the trap for over 10 hours, with occasional adjustment of the trapping laser frequency to account for drifts. The proposed test of the Standard Model will require accurate calculation of its atomic properties. We are currently testing these calculations by measuring other predicted quantities. (orig.)

Positron-trapping mechanism at dislocations in Zn

DEFF Research Database (Denmark)

Hidalgo, Carlos; Linderoth, Søren; Diego, Nieves de

1987-01-01

the average lifetime and the intensity of the long component decrease with increasing temperature. The experimental results are very well described in terms of a generalized trapping model where it is assumed that positrons become trapped in deep traps (jogs) via shallow traps (dislocation lines......). The temperature dependence of the positron-lifetime spectra below 120 K is attributed to the temperature dependence of the trapping rate to the dislocation line. The experimental results have demonstrated that detrapping processes from the dislocation line take place above 120 K. The positron binding energy...

Optimization and simulation of MEMS rectilinear ion trap

Directory of Open Access Journals (Sweden)

Huang Gang

2015-04-01

Full Text Available In this paper, the design of a MEMS rectilinear ion trap was optimized under simulated conditions. The size range of the MEMS rectilinear ion trap’s electrodes studied in this paper is measured at micron scale. SIMION software was used to simulate the MEMS rectilinear ion trap with different sizes and different radio-frequency signals. The ion-trapping efficiencies of the ion trap under these different simulation conditions were obtained. The ion-trapping efficiencies were compared to determine the performance of the MEMS rectilinear ion trap in different conditions and to find the optimum conditions. The simulation results show that for the ion trap at micron scale or smaller, the optimized length–width ratio was 0.8, and a higher frequency of radio-frequency signal is necessary to obtain a higher ion-trapping efficiency. These results have a guiding role in the process of developing MEMS rectilinear ion traps, and great application prospects in the research fields of the MEMS rectilinear ion trap and the MEMS mass spectrometer.

Stability of trapped electrons in SiO2

International Nuclear Information System (INIS)

Fleetwood, D.M.; Winokur, P.S.; Flament, O.; Leray, J.L.

1998-01-01

Electron trapping near the Si/SiO 2 interface plays a crucial role in mitigating the response of MOS devices to ionizing radiation or high-field stress. These electrons offset positive charge due to trapped holes, and can be present at densities exceeding 10 12 cm -2 in the presence of a similar density of trapped positive charge. The nature of the defects that serve as hosts for trapped electrons in the near-interfacial SiO 2 is presently unknown, although there is compelling evidence that these defects are often intimately associated with trapped holes. This association is depicted most directly in the model of Lelis et al., which suggests that trapped electrons and holes occupy opposite sides of a compensated E center in SiO 2 . Charge exchange between electron traps and the Si can occur over a wide range of time scales, depending on the trap depth and location relative to the Si/SiO 2 interface. Here the authors report a detailed study of the stability of electron traps associated with trapped holes near the Si/SiO 2 interface

The Aarhus Ion Micro-Trap Project

DEFF Research Database (Denmark)

Miroshnychenko, Yevhen; Nielsen, Otto; Poulsen, Gregers

As part of our involvement in the EU MICROTRAP project, we have designed, manufactured and assembled a micro-scale ion trap with integrated optical fibers. These prealigned fibers will allow delivering cooling laser light to single ions. Therefore, such a trap will not require any direct optical...... and installed in an ultra high vacuum chamber, which includes an ablation oven for all-optical loading of the trap [2]. The next steps on the project are to demonstrate the operation of the micro-trap and the cooling of ions using fiber delivered light. [1] D. Grant, Development of Micro-Scale Ion traps, Master...... Thesis (2008). [2] R.J. Hendricks, D.M. Grant, P.F. Herskind, A. Dantan and M. Drewsen, An all-optical ion-loading technique for scalable microtrap architectures, Applied Physics B, 88, 507 (2007)....

Sognenavne, Lemvig Kommune (18 artikler). trap.dk

DEFF Research Database (Denmark)

Kællerød, Lars-Jakob Harding

2017-01-01

Artikler til Trap Danmarks netpublikation trap.dk Sognenavnene Bøvling, Dybe, Engbjerg, Fabjerg, Ferring, Fjaltring, Flynder, Gudum, Heldum, Hygum, Lomborg, Møborg, Nees, Nørlem, Rom, Trans, Tørring og Vandborg......Artikler til Trap Danmarks netpublikation trap.dk Sognenavnene Bøvling, Dybe, Engbjerg, Fabjerg, Ferring, Fjaltring, Flynder, Gudum, Heldum, Hygum, Lomborg, Møborg, Nees, Nørlem, Rom, Trans, Tørring og Vandborg...

A search for mixotrophy and mucus trap production in Alexandrium spp. and the dynamics of mucus trap formation in Alexandrium pseudogonyaulax

DEFF Research Database (Denmark)

Blossom, Hannah Eva; Bædkel, Tina Dencker; Tillmann, Urban

2017-01-01

, such as speed and frequency of trap formation as well as what happens to the trap after the A. pseudogonyaulax cell detaches from it. The percentage of A. pseudogonyaulax cells producing a mucus trap and the number of prey cells caught increased with increasing prey concentration, whereas the physical size...... of the traps was independent of prey concentration. In one strain given an excess of prey, within 1 h over 90% of individual A. pseudogonyaulax cells had formed a trap, each containing an average of 45 prey cells. Individual A. pseudogonyaulax cells steadily produced traps and up to 5 traps were produced...

Charged particle traps II applications

CERN Document Server

Werth, Günther; Major, Fouad G

2009-01-01

This, the second volume of Charged Particle Traps, is devoted to applications, complementing the first volume’s comprehensive treatment of the theory and practice of charged particle traps, their many variants and refinements. In recent years, applications of far reaching importance have emerged ranging from the ultra-precise mass determinations of elementary particles and their antiparticles and short-lived isotopes, to high-resolution Zeeman spectroscopy on multiply-charged ions, to microwave and optical spectroscopy, some involving "forbidden" transitions from metastable states of such high resolution that optical frequency standards are realized by locking lasers to them. Further the potential application of trapped ions to quantum computing is explored, based on the extraordinary quantum state coherence made possible by the particle isolation. Consideration is given to the Paul and Penning traps as potential quantum information processors.

Trap-induced photoconductivity in singlet fission pentacene diodes

Energy Technology Data Exchange (ETDEWEB)

Qiao, Xianfeng, E-mail: qiaoxianfeng@hotmail.com; Zhao, Chen; Chen, Bingbing; Luan, Lin [WuHan National Laboratory for Optoelectronics and School of Optical and Electronic Information, Huazhong University of Science and Technology, Wu Han 430074 (China)

2014-07-21

This paper reports a trap-induced photoconductivity in ITO/pentacene/Al diodes by using current-voltage and magneto-conductance measurements. The comparison of photoconductivity between pentacene diodes with and without trap clearly shows that the traps play a critical role in generating photoconductivity. It shows that no observable photoconductivity is detected for trap-free pentacene diodes, while significant photoconductivity is observed in diodes with trap. This is because the initial photogenerated singlet excitons in pentacene can rapidly split into triplet excitons with higher binding energy prior to dissociating into free charge carriers. The generated triplet excitons react with trapped charges to release charge-carriers from traps, leading to a trap-induced photoconductivity in the single-layer pentacene diodes. Our studies elucidated the formation mechanisms of photoconductivity in pentacene diodes with extremely fast singlet fission rate.

Trapping molecules in two and three dimensions

International Nuclear Information System (INIS)

Pinkse, PW.H.; Junglen, T.; Rieger, T.; Rangwala, S.A.; Windpassinger, P.; Rempe, G.

2005-01-01

Full text: Cold molecules offer a new testing ground for quantum-physical effects in nature. For example, producing slow beams of large molecules could push experiments studying the boundary between quantum interference and classical particles up towards ever heavier particles. Moreover, cold molecules, in particular YbF, seem an attractive way to narrow down the constraints on the value of the electron dipole moment and finally, quantum information processing using chains of cold polar molecules or vibrational states in molecules have been proposed. All these proposals rely on advanced production and trapping techniques, most of which are still under development. Therefore, novel production and trapping techniques for cold molecules could offer new possibilities not found in previous methods. Electric traps hold promise for deep trap potentials for neutral molecules. Recently we have demonstrated two-dimensional trapping of polar molecules in a four-wire guide using electrostatic and electrodynamic trapping techniques. Filled from a thermal effusive source, such a guide will deliver a beam of slow molecules, which is an ideal source for interferometry experiments with large molecules, for instance. Here we report about the extension of this work to three-dimensional trapping. Polar molecules with a positive Stark shift can be trapped in the minimum of an electrostatic field. We have successfully tested a large volume electrostatic trap for ND3 molecules. A special feature of this trap is that it can be loaded continuously from an electrostatic guide, at a temperature of a few hundred mK. (author)

Economics of Developing Hot Stratigraphic Reservoirs

Energy Technology Data Exchange (ETDEWEB)

Greg Mines; Hillary Hanson; Rick Allis; Joseph Moore

2014-09-01

Stratigraphic geothermal reservoirs at 3 – 4 km depth in high heat-flow basins are capable of sustaining 100 MW-scale power plants at about 10 c/kWh. This paper examines the impacts on the levelized cost of electricity (LCOE) of reservoir depth and temperature, reservoir productivity, and drillhole/casing options. For a reservoir at 3 km depth with a moderate productivity index by hydrothermal reservoir standards (about 50 L/s/MPa, 5.6 gpm/psi), an LCOE of 10c/kWh requires the reservoir to be at about 200°C. This is the upper temperature limit for pumps. The calculations assume standard hydrothermal drilling costs, with the production interval completed with a 7 inch liner in an 8.5 inch hole. If a reservoir at 4 km depth has excellent permeability characteristics with a productivity index of 100 L/s/MPa (11.3 gpm/psi), then the LCOE is about 11 c/kWh assuming the temperature decline rate with development is not excessive (< 1%/y, with first thermal breakthrough delayed by about 10 years). Completing wells with modest horizontal legs (e.g. several hundred meters) may be important for improving well productivity because of the naturally high, sub-horizontal permeability in this type of reservoir. Reducing the injector/producer well ratio may also be cost-effective if the injectors are drilled as larger holes.

WheelerLab: An interactive program for sequence stratigraphic analysis of seismic sections, outcrops and well sections and the generation of chronostratigraphic sections and dynamic chronostratigraphic sections

OpenAIRE

Adewale Amosu; Yuefeng Sun

2017-01-01

WheelerLab is an interactive program that facilitates the interpretation of stratigraphic data (seismic sections, outcrop data and well sections) within a sequence stratigraphic framework and the subsequent transformation of the data into the chronostratigraphic domain. The transformation enables the identification of significant geological features, particularly erosional and non-depositional features that are not obvious in the original seismic domain. Although there are some software produ...

Antimatter Plasmas in a Multipole Trap for Antihydrogen

CERN Document Server

Andresen, G B; Boston, A; Bowe, P D; Cesar, C L; Chapman, S; Charlton, M; Chartier, M; Deutsch, A; Fajans, J; Fujiwara, M C; Funakoshi, R; Gill, D R; Gomberoff, K; Hangst, J S; Hayano, R S; Hydomako, R; Jenkins, M J; Jørgensen, L V; Kurchaninov, L; Madsen, N; Nolan, P; Olchanski, K; Olin, A; Povilus, A; Robicheaux, F; Sarid, E; Silveira, D M; Storey, J W; Telle, H H; Thompson, R I; van der Werf, D P; Wurtele, J S; Yamazaki, Y

2007-01-01

We have demonstrated storage of plasmas of the charged constituents of the antihydrogen atom, antiprotons and positrons, in a Penning trap surrounded by a minimum-B magnetic trap designed for holding neutral antiatoms. The neutral trap comprises a superconducting octupole and two superconducting, solenoidal mirror coils. We have measured the storage lifetimes of antiproton and positron plasmas in the combined Penning-neutral trap, and compared these to lifetimes without the neutral trap fields. The magnetic well depth was 0.6 T, deep enough to trap ground state antihydrogen atoms of up to about 0.4 K in temperature. We have demonstrated that both particle species can be stored for times long enough to permit antihydrogen production and trapping studies.

Antimatter plasmas in a multipole trap for antihydrogen.

Science.gov (United States)

Andresen, G; Bertsche, W; Boston, A; Bowe, P D; Cesar, C L; Chapman, S; Charlton, M; Chartier, M; Deutsch, A; Fajans, J; Fujiwara, M C; Funakoshi, R; Gill, D R; Gomberoff, K; Hangst, J S; Hayano, R S; Hydomako, R; Jenkins, M J; Jørgensen, L V; Kurchaninov, L; Madsen, N; Nolan, P; Olchanski, K; Olin, A; Povilus, A; Robicheaux, F; Sarid, E; Silveira, D M; Storey, J W; Telle, H H; Thompson, R I; van der Werf, D P; Wurtele, J S; Yamazaki, Y

2007-01-12

We have demonstrated storage of plasmas of the charged constituents of the antihydrogen atom, antiprotons and positrons, in a Penning trap surrounded by a minimum-B magnetic trap designed for holding neutral antiatoms. The neutral trap comprises a superconducting octupole and two superconducting, solenoidal mirror coils. We have measured the storage lifetimes of antiproton and positron plasmas in the combined Penning-neutral trap, and compared these to lifetimes without the neutral trap fields. The magnetic well depth was 0.6 T, deep enough to trap ground state antihydrogen atoms of up to about 0.4 K in temperature. We have demonstrated that both particle species can be stored for times long enough to permit antihydrogen production and trapping studies.

Experimental pseudo-symmetric trap EPSILON

International Nuclear Information System (INIS)

Skovoroda, A.A.; Arsenin, V.V.; Dlougach, E.D.; Kulygin, V.M.; Kuyanov, A.Yu.; Timofeev, A.V.; Zhil'tsov, V.A.; Zvonkov, A.V.

2001-01-01

Within the framework of the conceptual project 'Adaptive Plasma EXperiment' a trap with the closed magnetic field lines 'Experimental Pseudo-Symmetric trap' is examined. The project APEX is directed at the theoretical and experimental development of physical foundations for stationary thermonuclear reactor on the basis of an alternative magnetic trap with tokamak-level confinement of high β plasma. The fundamental principle of magnetic field pseudosymmetry that should be satisfied for plasma to have tokamak-like confinement is discussed. The calculated in paraxial approximation examples of pseudosymmetric curvilinear elements with poloidal direction of B isolines are adduced. The EPSILON trap consisting of two straight axisymmetric mirrors linked by two curvilinear pseudosymmetric elements is considered. The plasma currents are short-circuited within the curvilinear element what increases the equilibrium β. The untraditional scheme of MHD stabilization of a trap with the closed field lines by the use of divertor inserted into axisymmetric mirror is analyzed. The experimental installation EPSILON-OME that is under construction for experimental check of divertor stabilization is discussed. The possibility of ECR plasma production in EPSILON-OME under conditions of high density and small magnetic field is examined. (author)

THE MIDDLE TO UPPER PALEOLITHIC SEQUENCE OF BURAN-KAYA III (CRIMEA, UKRAINE) : NEW STRATIGRAPHIC, PALEOENVIRONMENTAL, AND CHRONOLOGICAL RESULTS

NARCIS (Netherlands)

Pean, Stephane; Puaud, Simon; Crepin, Laurent; Prat, Sandrine; Quiles, Anita; van der Plicht, Johannes; Valladas, Helene; Stuart, Anthony J.; Drucker, Dorothee G.; Patou-Mathis, Marylene; Lanoe, Francois; Yanevich, Aleksandr; Hatté, C.; Jull, A.J.T.

2013-01-01

Buran-Kaya III is a rockshelter located in Crimea (Ukraine). It provides an exceptional stratigraphic sequence extending from the Middle Paleolithic to the Neolithic. Nine Paleolithic layers have been attributed to the Streletskaya or eastern Szeletian, Micoquian, Aurignacian, Gravettian, and

Possible Triggering of the Largest Deccan Traps Eruptions By the Chicxulub Impact

Science.gov (United States)

Richards, M. A.; Alvarez, W.; Self, S.; Karlstrom, L.; Renne, P. R.; Manga, M.; Sprain, C. J.; Smit, J.; Vanderkluysen, L.; Gibson, S. A.

2014-12-01

New constraints on the timing of the Cretaceous-Paleogene (K-Pg) mass extinction and the Chicxulub impact, together with a particularly voluminous and apparently brief eruptive pulse toward the end of the "main-stage" eruptions of the Deccan continental flood basalt province, suggest that these three events may have occurred within less than about a hundred thousand years of each other. Partial melting induced by the Chicxulub event does not provide an energetically-plausible explanation for this coincidence, and both geochronologic and magnetic-polarity data show that Deccan volcanism was underway well before Chicxulub/K-Pg time. However, historical data document that eruptions from existing volcanic systems can be triggered by earthquakes. Seismic modeling of the ground motion due to the Chicxulub impact suggests that the impact could have generated seismic energy densities of order 0.1-1.0 J/m3 throughout the upper ~200 km of the Earth's mantle, sufficient to trigger volcanic eruptions worldwide based upon comparison with historical examples. Triggering may have been caused by a transient increase in the effective permeability of the existing deep magmatic system beneath the Deccan province, or mantle plume "head." It is therefore reasonable to hypothesize that the Chicxulub impact might have triggered the enormous Poladpur, Ambenali, and Mahabaleshwar (Wai sub-group) lava flows that account for >70% of the Deccan Traps main-stage eruptions. This hypothesis is consistent with independent stratigraphic, geochronologic, geochemical, and tectonic constraints, which combine to indicate that at approximately Chicxulub/K-Pg time a huge pulse of mantle plume-derived magma passed through the crust with little interaction, and erupted to form the most extensive and voluminous lava flows known on Earth. High-precision radioisotopic dating of the main-phase Deccan flood basalt formations may be able either to confirm or reject this hypothesis, which in turn might help

A Rotating-Bears Optical Dipole Trap for Cold Aatoms

International Nuclear Information System (INIS)

Friedman, N.; Ozeri, R.; Khaykovich, L.; Davidson, N.

1999-01-01

In the last few years, several optical dipole traps for cold atoms were demonstrated and used to study cold atomic collisions, long atomic coherence times and quantum collective effects. Blue-detuned dipole traps, where repulsive light forces confines atoms mostly in dark, offer long storage, and photon-scattering times, combined with strong confinement forces. Unfortunately, such blue-detuned dipole traps involve complicated light intensity distributions that require either multiple laser beams or complicated phase elements. Here, we propose and demonstrate a novel configuration for a single-beam blue-detuned dipole trap, which enables larger trapping volume, and fast temporal changes in the trap size and shape. Our trap consists of a tightly-focused laser beam which is rapidly rotated (with rotation frequency up to 400 khz) with two orthogonal acousto optical scanners. For very high rotation frequencies the atoms feel a time-averaged static dipole potential. Therefore, when the radius of rotation is larger than the beam size, a dark volume which is completely surrounded by light is obtained around the focal region. By changing the rotation radius and the trapping laser intensity and detuning, the trap dimensions and oscillation frequency could be changed over a large parameter range. In particular trap diameters were changed between 50 to 220 microns and trap length was changed between 3.5 to 16 mm. ∼10 6 atoms were loaded into the rotating-beam dipole trap from a magneto optical trap. The density of the trapped atoms was 4x10 10 atoms/cm 3 ,their temperature was -6 pK. and the trap (1/e) lifetime was 0.65 sec, limited by collisions with background atoms. When the rotation frequency was decreased below the oscillation frequency of the atoms in the trap, the trap became unstable, and a sharp reduction of the trap lifetime was observed, in agreement with our theoretical analysis. Finally, we demonstrated adiabatic compression of atoms in the trap by decreasing

Performance and regeneration of a pellet-packed-bed diesel-particulate trap; Ryutai jutenso diesel biryushi trap no seino oyobi saisei

Energy Technology Data Exchange (ETDEWEB)

Shioji, M; Nakai, S; Ikegami, M [Kyoto University, Kyoto (Japan); Hori, Y [Yamaha Motor Co. Ltd., Shizuoka (Japan)

1997-10-01

This paper demonstrates with the feasibility of a pellet-packed bed for trapping diesel particulates. After making pellets loose from the packed condition, regeneration is established by a circulation of pellets in the trap and collected particulates are efficiently dropped out through the wire mesh on the bottom of the trap. An experimental trap with the pellet-circulation system using a spiral feeder is tested on a single-cylinder test engine to show the trap and regeneration efficiencies. In addition, the condition of pellet circulation is observed using the transparent cylinder, based on which the design of pellet and trap sizes are discussed. 6 refs., 10 figs.

Study on the application of seismic sedimentology in a stratigraphic-lithologic reservoir in central Junggar Basin

Science.gov (United States)

Yu, Yixin; Xia, Zhongmou

2017-06-01

This paper discusses the research idea of description for stratigraphic-lithologic reservoir based on seismic sedimentology methods. The sandstone reservoir of Jurrassic XiShanyao Formation in Junggar Basin is studied according to the theory and approaches of seismic sedimentology. By making full use of borehole data, the technologies of layer correlation based on the stratigraphic sequence framework, the forward seismic modeling, the stratal slicing and lithologic inversion are applied. It describes the range of denudation line, the distribution characteristics of sedimentary facies of the strata, the vertical and horizontal distribution of sand bodies and the favourable oil-gas bearing prospective area. The results shows that study area are dominated braided delta deposition including underwater distributary channel and distributary bay microfacies, the nip-out lines of the formation are northeast to southwest from north to south, the second Middle Jurassic sand body is the most widely distributed one among three sand bodies, the prospective oil-gas bearing area located in the south part and around the YG2 well area. The study result is effective on the practice of exploration in study area.

Sognenavne, Aabenraa Kommune (16 artikler). trap.dk

DEFF Research Database (Denmark)

Kællerød, Lars-Jakob Harding

2019-01-01

Artikler til Trap Danmarks netpublikation trap.dk Sognenavnene Bjolderup, Burkal, Bylderup, Egvad, Ensted, Genner, Hellevad, Hjordkær, Holbøl, Kliplev, Løjt, Ravsted, Rise, Uge, Varnæs og Øster Løgum......Artikler til Trap Danmarks netpublikation trap.dk Sognenavnene Bjolderup, Burkal, Bylderup, Egvad, Ensted, Genner, Hellevad, Hjordkær, Holbøl, Kliplev, Løjt, Ravsted, Rise, Uge, Varnæs og Øster Løgum...

Impacts of silvicultural thinning treatments on beetle trap captures and tree attacks during low bark beetle populations in ponderosa pine forests of northern Arizona.

Science.gov (United States)

Gaylord, M L; Hofstetter, R W; Wagner, M R

2010-10-01

Our research used a combination of passive traps, funnel traps with lures, baited trees, and surveys of long-term thinning plots to assess the impacts of different levels of stand basal area (BA) on bark beetle tree attack and on trap captures of Ips spp., Dendroctonus spp., and their predators. The study occurred at two sites in ponderosa pine, Pinus ponderosa Dougl. ex Laws., forests, from 2004 to 2007 during low bark beetle populations. Residual stand BA ranged from 9.0 to 37.0 m2/ha. More predators and bark beetles were collected in passive traps in stands of lower BA than in stands of higher BA; however, significance varied by species and site, and total number of beetles collected was low. Height of the clear panel passive traps affected trap catches for some species at some sites and years. When pheromone lures were used with funnel traps [Ips pini (Say) lure: lanierone, +03/-97 ipsdienol], we found no significant difference in trap catches among basal area treatments for bark beetles and their predators. Similarly, when trees were baited (Dendroctonus brevicomis LeConte lure: myrcene, exo-brevicomin and frontalin), we found no significant difference for days to first bark beetle attack. Surveys of long-term thinning treatments found evidence of bark beetle attacks only in unthinned plots (approximately 37 m2/ha basal area). We discuss our results in terms of management implications for bark beetle trapping and control.

Deuterium trapping in carbon fiber composites under high fluence

International Nuclear Information System (INIS)

Airapetov, A.A.; Begrambekov, L.B.; Kuzmin, A.A.; Shigin, P.A.; Zakharov, A.M.

2010-01-01

The paper is devoted to investigation of deuterium trapping in CFC, dance graphite MPG-8 and pyrolytic graphite (PG) under plasma ion- and electron irradiation. Number of specific features of deuterium trapping and retention under plasma ion and electron irradiation is presented and discussed. In particular it is shown that 1) deuterium trapping takes place even when energy of impinging ions approaches zero; 2) deuterium is trapped under irradiation by plasma electrons; 3) under irradiation at equal fluences deuterium trapping is higher, when ion flux is smaller. High energy ion penetrating the surfaces are trapped in the traps created at the expense of their kinetic energy. The process may be named 'kinetic trapping'. Under low energy (smaller than 200 eV) electron and/or ion irradiation the energy of inelastic interaction on the surface provides creation of active centers, which initiate dissociation of deuterium sorbed on the surface, penetration of deuterium atoms into graphite and their trapping in specific low energy traps. The term 'potential trapping' is proposed for this type of trapping. Under high energy irradiation such atoms can fill the traps formed through kinetic mechanism. Origination of moveable deuterium atoms from the layer of surface sorption seems to be time dependent process and it is a reason of increase of trapping along with irradiation time. New features of deuterium trapping and retention in graphite evaluated in this study offer new opportunities for analysis and correct estimation of hydrogen isotope trapping and retention in tokamaks having graphite tiles. (authors)

Asymmetric ion trap

Science.gov (United States)

Barlow, Stephan E.; Alexander, Michael L.; Follansbee, James C.

1997-01-01

An ion trap having two end cap electrodes disposed asymmetrically about a center of a ring electrode. The inner surface of the end cap electrodes are conformed to an asymmetric pair of equipotential lines of the harmonic formed by the application of voltages to the electrodes. The asymmetry of the end cap electrodes allows ejection of charged species through the closer of the two electrodes which in turn allows for simultaneously detecting anions and cations expelled from the ion trap through the use of two detectors charged with opposite polarity.

Developing optical traps for ultra-sensitive analysis

International Nuclear Information System (INIS)

Zhao, X.; Vieira, D.J.; Guckert, R.; Crane, S.

1998-01-01

The authors describe the coupling of a magneto-optical trap to a mass separator for the ultra-sensitive detection of selected radioactive species. As a proof of principle test, they have demonstrated the trapping of ∼ 6 million 82 Rb (t 1/2 = 75 s) atoms using an ion implantation and heated foil release method for introducing the sample into a trapping cell with minimal gas loading. Gamma-ray counting techniques were used to determine the efficiencies of each step in the process. By far the weakest step in the process is the efficiency of the optical trap itself (0.3%). Further improvements in the quality of the nonstick dryfilm coating on the inside of the trapping cell and the possible use of larger diameter laser beams are indicated. In the presence of a large background of scattered light, this initial work achieved a detection sensitivity of ∼ 4,000 trapped atoms. Improved detection schemes using a pulsed trap and gated photon detection method are outlined. Application of this technology to the areas of environmental monitoring and nuclear proliferation are foreseen

Improving detection tools for emerald ash borer (Coleoptera: Buprestidae): comparison of multifunnel traps, prism traps, and lure types at varying population densities.

Science.gov (United States)

Crook, Damon J; Francese, Joseph A; Rietz, Michael L; Lance, David R; Hull-Sanders, Helen M; Mastro, Victor C; Silk, Peter J; Ryall, Krista L

2014-08-01

The emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is a serious invasive pest of North American ash (Fraxinus spp.) that has caused devastating mortality since it was first identified in North America in 2002. In 2012, we conducted field trapping assays that tested the efficacy of purple prism and fluon-coated green multifunnel (Lindgren funnel) traps. Traps were baited with combinations of several lures that were previously shown to be attractive to A. planipennis: manuka oil--a sesquiterpene-rich oil, (3Z)-hexenol--a green leaf volatile, or (3Z)-dodecen-12-olide [= (3Z)-lactone], a sex pheromone. Eighty-nine blocks (trap lines) were tested throughout nine states along the outer edges of the currently known A. planipennis infestation in North America. Trap catch was highest on fluon-coated green multifunnel traps, and trap detections at sites with low A. planipennis population density ranged from 72 to 76% for all trap and lure types tested. (3Z)-hexenol and (3Z)-lactone baited traps functioned as well as (3Z)-hexenol and manuka oil-baited traps. Independent of the lure used, detection rates on green fluon-coated multifunnel traps were comparable with glued purple prism traps in areas with low A. planipennis population densities.

An EPR study of positive hole transfer and trapping in irradiated frozen solutions containing aromatic traps

International Nuclear Information System (INIS)

Egorov, A.V.; Zezin, A.A.; Feldman, V.I.

2002-01-01

Complete text of publication follows. Processes of positive hole migration and trapping are of basic significance for understanding of the primary events in the radiation chemistry of solid molecular systems. Specific interest is concerned with the case, when ionization energies of 'hole traps' are rather close, so one may expect 'fine tuning' effects resulting from variations in conformation, weak interactions, molecular packing, etc. In this contribution we report the results of EPR study of formation of radical cations in irradiated frozen halocarbon solutions containing aromatic molecules of different structure. Using the 'two-trap' model made it possible to obtain an evidence for efficient long-range trap-to-trap positive hole transfer between alkyl benzene molecules with close ionization energies distributed in the matrices with high ionization potentials. The distance of transfer was found to be 2-4 nm. In the case of frozen solutions containing ethylbenzene and toluene, it was found that the efficiency and direction of hole transfer was controlled by the conformation of ethylbenzene radical cation. The study of positive hole localization in 'bridged' diphenyls of Ph(CH 2 ) n Ph type revealed that the structure of radical cations of these species was affected by local environment (type of halocarbon matrix) and the conformational flexibility of 'bridge'. In summary, we may conclude that migration and localization of positive hole in rigid systems containing aromatic 'traps' is quite sensitive to rather subtle effects. This conclusion may be of common significance for the radiation chemistry of systems with physical dispersion of the traps of similar chemical structure (e.g. macromolecules, adsorbed molecules, etc.)

Cold trap disposed within a tank

International Nuclear Information System (INIS)

Kanbe, Mitsuru.

1983-01-01

Purpose: To improve the reliability and the durability of cold traps by simplifying the structure and recycling liquid metals without using electromagnetic pumps. Constitution: The reactor container is partitioned by an intermediate container enhousing primary recycling pumps and cold traps. The inlet and the exit for the liquid metal of each cold trap are opened to the outside and the inside of the intermediate container respectively. In such a structure, the pressure difference between the inside and the outside of the intermediate container is exerted on the cold traps due to the exhaust pressure of the recycling pumps in which the liquid metal flowing into the cold traps is purified through filters, cooled and then discharged from the exit to the cold plenum. In this way, liquid metal can be recycled without using an electromagnetic pump whose reliability has not yet been established. (Kamimura, M.)

Nonadiabatic transitions in electrostatically trapped ammonia molecules

International Nuclear Information System (INIS)

Kirste, Moritz; Schnell, Melanie; Meijer, Gerard; Sartakov, Boris G.

2009-01-01

Nonadiabatic transitions are known to be major loss channels for atoms in magnetic traps but have thus far not been experimentally reported upon for trapped molecules. We have observed and quantified losses due to nonadiabatic transitions for three isotopologues of ammonia in electrostatic traps by comparing the trapping times in traps with a zero and a nonzero electric field at the center. Nonadiabatic transitions are seen to dominate the overall loss rate even for the present samples that are at relatively high temperatures of 30 mK. It is anticipated that losses due to nonadiabatic transitions in electric fields are omnipresent in ongoing experiments on cold molecules.

How to detect trap cluster systems?

International Nuclear Information System (INIS)

Mandowski, Arkadiusz

2008-01-01

Spatially correlated traps and recombination centres (trap-recombination centre pairs and larger clusters) are responsible for many anomalous phenomena that are difficult to explain in the framework of both classical models, i.e. model of localized transitions (LT) and the simple trap model (STM), even with a number of discrete energy levels. However, these 'anomalous' effects may provide a good platform for identifying trap cluster systems. This paper considers selected cluster-type effects, mainly relating to an anomalous dependence of TL on absorbed dose in the system of isolated clusters (ICs). Some consequences for interacting cluster (IAC) systems, involving both localized and delocalized transitions occurring simultaneously, are also discussed

The LPCTrap facility for in-trap decay experiments

International Nuclear Information System (INIS)

Rodriguez, D.; Ban, G.; Durand, D.; Duval, F.; Flechard, X.; Herbane, M.; Lienard, E.; Mauger, F.; Mery, A.; Naviliat-Cuncic, O.; Thomas, J.-C.

2007-01-01

The LPCTrap facility is coupled to the low-energy beam line LIRAT of the SPIRAL source at GANIL (France). The facility comprises an RFQ trap for beam preparation and a transparent Paul trap for in-trap decay studies. The system has been tested for several ion species. The Paul trap has been fully characterized for 6 Li + and 23 Na + ions. This characterization together with GEANT4 simulations of the in-trap decay setup (Paul trap and detection system) has permitted to predict the effect of the size of the ion cloud on the decay study of 6 He + .

Line-Trapping of Codling Moth (Lepidoptera: Tortricidae): A Novel Approach to Improving the Precision of Capture Numbers in Traps Monitoring Pest Density.

Science.gov (United States)

Adams, C G; McGhee, P S; Schenker, J H; Gut, L J; Miller, J R

2017-08-01

This field study of codling moth, Cydia pomonella (L.), response to single versus multiple monitoring traps baited with codlemone demonstrates that precision of a given capture number is alarmingly poor when the population is held constant by releasing moths. Captures as low as zero and as high as 12 males per single trap are to be expected where the catch mode is three. Here, we demonstrate that the frequency of false negatives and overestimated positives for codling moth trapping can be substantially reduced by employing the tactic of line-trapping, where five traps were deployed 4 m apart along a row of apple trees. Codling moth traps spaced closely competed only slightly. Therefore, deploying five traps closely in a line is a sampling technique nearly as good as deploying five traps spaced widely. But line trapping offers a substantial savings in time and therefore cost when servicing aggregated versus distributed traps. As the science of pest management matures by mastering the ability to translate capture numbers into estimates of absolute pest density, it will be important to employ a tactic like line-trapping so as to shrink the troublesome variability associated with capture numbers in single traps that thwarts accurate decisions about if and when to spray. Line-trapping might similarly increase the reliability and utility of density estimates derived from capture numbers in monitoring traps for various pest and beneficial insects. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

Stratigraphic and structural compartmentalization observed within a model turbidite reservoir, Pennsylvanian Upper Jackfork Formation, Hollywood Quarry, Arkansas

Energy Technology Data Exchange (ETDEWEB)

Slatt, R. [Colorado School of Mines, Golden, CO (United States); Jordan, D. [Arco International Oil and Gas Co., Plano, TX (United States); Stone, C. [Arkansas Geological Commission, Little Rock, AR (United States)] [and others

1995-08-01

Hollywood Quarry is a 600 x 375 x 150 ft. (200 x 125 x 50m) excavation which provides a window into lower Pennsylvanian Jackfork Formation turbidite stratal architecture along the crest of a faulted anticlinal fold. A variety of turbidite facies are present, including: (a) lenticular, channelized sandstones, pebbly sandstones, and conglomerates within shale, (b) laterally continuous, interbedded thin sandstones and shales, and (c) thicker, laterally continuous shales. The sandstone and shale layers we broken by several strike-slip and reverse faults, with vertical displacements of up to several feet. This combination of facies and structural elements has resulted in a highly compartmentalized stratigraphic interval, both horizontally and vertically, along the anticlinal flexure. The quarry can be considered analogous to a scaled-down turbidite reservoir. Outcrop gamma-ray logs, measured sections, a fault map, and cross sections provide a database which is analogous to what would be available for a subsurface reservoir. Thus, the quarry provides an ideal outdoor geologic and engineering {open_quote}workshop{close_quote} venue for visualizing the potential complexities of a combination structural-stratigraphic (turbidite) reservoir. Since all forms of compartmentalization are readily visible in the quarry, problems related to management of compartmentalized reservoirs can be discussed and analyzed first-hand while standing in the quarry, within this {open_quote}model reservoir{close_quotes}. These problems include: (a) the high degree of stratigraphic and structural complexity that may be encountered, even at close well spacings, (b) uncertainty in well log correlations and log-shape interpretations, (c) variations in volumetric calculations as a function of amount of data available, and (d) potential production problems associated with specific {open_quote}field{close_quote} development plans.

Medfly female attractant trapping studies in Guatemala

International Nuclear Information System (INIS)

Jeronimo, F.; Rendon, P.; Villatoro, C.

1999-01-01

Experiments were conducted from 1994 - 1998 to test the attractiveness of combinations of food-based chemicals for C. capitata (medfly) in Guatemala. Most studies were done in coffee. The 1995 studies, using the FA-2 attractants (ammonium acetate and putrescine) showed that this combination was attractive for females and had potential for use in conjunction with a SIT program. The 1996 studies at three elevations demonstrated that, in general, these attractants, when used in either the Open Bottom Dry Trap (OBDT), Closed Bottom Dry Trap (CBDT), or International Pheromone's McPhail Trap (IPMT) performed better than the Jumbo McPhail trap (JMT) baited with NuLure and borax (NU+B) for capture of feral females. At the high elevation (1400 m), the IPMT with FA-2 and OBDT with FA-2 were best; at the middle elevation (1100 m), the ORDT, IPMT, and CBDT with FA-2 were best; and at low elevations (659 m), the IPMT with FA-2, JMT with NU+B and ORDT with FA-2 were equal in performance. At the middle elevation, using sterile flies, the OBDT with FA-2 worked best. When experiments were carried out in pear, the traps using the FA-2 attractants captured more female flies than the JMT, NU+B, but not significantly more. During the 1997 trials, a third component, trimethylamine was added to the two component lure (FA-3). This attractant was tested in a number of locally produced traps using 2 I soft drink bottles with different color bottoms. The dry versions of the traps contained a yellow sticky insert. All study sites were at low elevation 600 - 650 m, in coffee, testing both sterile and feral flies. With the feral flies during the first phase of the study at finca San Carlos, there were no significant differences between treatments, at finca San Luis, the clear local trap with sticky insert and the green local trap with sticky insert were best, and at finca Valapraiso, the green local trap with yellow sticky insert and yellow local trap with sticky insert captured more flies

Trapping technology for gaseous fission products from voloxidation process

International Nuclear Information System (INIS)

Shin, Jin Myeong; Park, J. J.; Park, G. I.; Jung, I. H.; Lee, H. H.; Kim, G. H.; Yang, M. S.

2005-05-01

The objective of this report is to review the different technologies for trapping the gaseous wastes containing Cs, Ru, Tc, 14 C, Kr, Xe, I and 3 H from a voloxidation process. Based on literature reviews and KAERI's experimental results on the gaseous fission products trapping, appropriate trapping method for each fission product has been selected considering process reliability, simplicity, decontamination factor, availability, and disposal. Specifically, the most promising trapping method for each fission product has been proposed for the development of the INL off-gas trapping system. A fly ash filter is proposed as a trapping media for a cesium trapping unit. In addition, a calcium filter is proposed as a trapping media for ruthenium, technetium, and 14 C trapping unit. In case of I trapping unit, AgX is proposed. For Kr and Xe, adsorption on solid is proposed. SDBC (Styrene Divinyl Benzene Copolymer) is also proposed as a conversion media to HTO for 3 H. This report will be used as a useful means for analyzing the known trapping technologies and help selecting the appropriate trapping methods for trapping volatile and semi-volatile fission products, long-lived fission products, and major heat sources generated from a voloxidation process. It can also be used to design an off-gas treatment system

High-fidelity operations in microfabricated surface ion traps

Science.gov (United States)

Maunz, Peter

2017-04-01

Trapped ion systems can be used to implement quantum computation as well as quantum simulation. To scale these systems to the number of qubits required to solve interesting problems in quantum chemistry or solid state physics, the use of large multi-zone ion traps has been proposed. Microfabrication enables the realization of surface electrode ion traps with complex electrode structures. While these traps may enable the scaling of trapped ion quantum information processing (QIP), microfabricated ion traps also pose several technical challenges. Here, we present Sandia's trap fabrication capabilities and characterize trap properties and shuttling operations in our most recent high optical access trap (HOA-2). To demonstrate the viability of Sandia's microfabricated ion traps for QIP we realize robust single and two-qubit gates and characterize them using gate set tomography (GST). In this way we are able to demonstrate the first single qubit gates with a diamond norm of less than 1 . 7 ×10-4 , below a rigorous fault tolerance threshold for general noise of 6 . 7 ×10-4. Furthermore, we realize Mølmer-Sørensen two qubit gates with a process fidelity of 99 . 58(6) % also characterized by GST. These results demonstrate the viability of microfabricated surface traps for state of the art quantum information processing demonstrations. This research was funded, in part, by the Office of the Director of National Intelligence (ODNI), Intelligence Advanced Research Projects Activity (IARPA).

Biases in Drosophila melanogaster protein trap screens

Directory of Open Access Journals (Sweden)

Müller Ilka

2009-05-01

Full Text Available Abstract Background The ability to localise or follow endogenous proteins in real time in vivo is of tremendous utility for cell biology or systems biology studies. Protein trap screens utilise the random genomic insertion of a transposon-borne artificial reporter exon (e.g. encoding the green fluorescent protein, GFP into an intron of an endogenous gene to generate a fluorescent fusion protein. Despite recent efforts aimed at achieving comprehensive coverage of the genes encoded in the Drosophila genome, the repertoire of genes that yield protein traps is still small. Results We analysed the collection of available protein trap lines in Drosophila melanogaster and identified potential biases that are likely to restrict genome coverage in protein trap screens. The protein trap screens investigated here primarily used P-element vectors and thus exhibit some of the same positional biases associated with this transposon that are evident from the comprehensive Drosophila Gene Disruption Project. We further found that protein trap target genes usually exhibit broad and persistent expression during embryonic development, which is likely to facilitate better detection. In addition, we investigated the likely influence of the GFP exon on host protein structure and found that protein trap insertions have a significant bias for exon-exon boundaries that encode disordered protein regions. 38.8% of GFP insertions land in disordered protein regions compared with only 23.4% in the case of non-trapping P-element insertions landing in coding sequence introns (p -4. Interestingly, even in cases where protein domains are predicted, protein trap insertions frequently occur in regions encoding surface exposed areas that are likely to be functionally neutral. Considering the various biases observed, we predict that less than one third of intron-containing genes are likely to be amenable to trapping by the existing methods. Conclusion Our analyses suggest that the

Reversible photo-induced trap formation in mixed-halide hybrid perovskites for photovoltaics.

Science.gov (United States)

Hoke, Eric T; Slotcavage, Daniel J; Dohner, Emma R; Bowring, Andrea R; Karunadasa, Hemamala I; McGehee, Michael D

2015-01-01

We report on reversible, light-induced transformations in (CH 3 NH 3 )Pb(Br x I 1- x ) 3 . Photoluminescence (PL) spectra of these perovskites develop a new, red-shifted peak at 1.68 eV that grows in intensity under constant, 1-sun illumination in less than a minute. This is accompanied by an increase in sub-bandgap absorption at ∼1.7 eV, indicating the formation of luminescent trap states. Light soaking causes a splitting of X-ray diffraction (XRD) peaks, suggesting segregation into two crystalline phases. Surprisingly, these photo-induced changes are fully reversible; the XRD patterns and the PL and absorption spectra revert to their initial states after the materials are left for a few minutes in the dark. We speculate that photoexcitation may cause halide segregation into iodide-rich minority and bromide-enriched majority domains, the former acting as a recombination center trap. This instability may limit achievable voltages from some mixed-halide perovskite solar cells and could have implications for the photostability of halide perovskites used in optoelectronics.

Lithostratigraphy and volcanology of the Serra Geral Group, Paraná-Etendeka Igneous Province in Southern Brazil: Towards a formal stratigraphical framework

Science.gov (United States)

Rossetti, Lucas; Lima, Evandro F.; Waichel, Breno L.; Hole, Malcolm J.; Simões, Matheus S.; Scherer, Claiton M. S.

2018-04-01

The volcanic rocks of the Lower Cretaceous Paraná-Etendeka Igneous Province, in Brazil, are grouped in the Serra Geral Group. The province can be chemically divided into low-TiO2, and high-TiO2. In southern Brazil, the low-TiO2 lava pile reaches a thickness of 1 km and is formed of heterogeneous lava packages here divided into four lava formations. Torres Formation (TF) is characterized by chemically more primitive basaltic (> 5 wt% MgO) compound pahoehoe flow fields; these lavas stratigraphically overly aeolian sandstones of Botucatu Formation and represent the onset of the volcanic activity. Vale do Sol Formation (VSF) groups vertically stacked sheet-like rubbly pahoehoe basaltic andesites (SiO2 > 51 wt%; MgO < 5 wt%). These lavas covered the former basalts in the Torres Syncline axis and pinch out towards southwest and represent the most voluminous mafic lava flows. Dacites and rhyolites of Palmas Formation (PF) overlay VSF flows in the central and eastern outcrop area and rest directly upon TF lavas in the west. The acidic units were emplaced as lava domes and widespread tabular lava flows. Esmeralda Formation (EF) is the upper stratigraphic unit and it is formed by a basaltic pahoehoe flow field emplaced during the waning phase of volcanic activity of the low-TiO2 lava sequence. Sedimentary interbeds are preserved throughout the whole lava pile and were deposited during quiescence periods of volcanic activity, and represent important stratigraphic markers (e.g. TF-VSF contact). The newly proposed stratigraphy provides promptly recognized stratigraphic units in a regional framework of fundamental importance for future correlations and provide vital information in the understanding of how the Paraná-Etendeka Igneous Province evolved through time.

Theory of resistive magnetohydrodynamic instabilities excited by energetic trapped particles in large-size tokamaks

International Nuclear Information System (INIS)

Biglari, H.

1987-01-01

A theory describing excitation of resistive magnetohydrodynamic instabilities due to a population of energetic particles, trapped in region of adverse curvature on energetic particles, trapped in region of adverse curvature in tokamaks, is presented. Theory's principal motivation is observation that high magnetic-field strengths and large geometric dimensions characteristic of present-generation thermonuclear fusion devices, places them in a frequency regime whereby processional drift frequency of auxiliary hot-ion species, in order of magnitude, falls below a typical inverse resistive interchange time scale, so that inclusion of resistive dissipation effects becomes important. Destabilization of the resistive internal kink mode by these suprathermal particles is first investigated. Using variational techniques, a generalized dispersion relation governing such modes, which recovers ideal theory in its appropriate limit, is derived and analyzed using Nyquist-diagrammatic techniques. An important implication of theory for present-generation fusion devices is that they will be stable to fishbone activity. Interaction of energetic particles with resistive interchange-ballooning modes is taken up. A population of hot particles, deeply trapped on adverse curvature side in tokamaks, can resonantly destabilize resistive interchange mode, which is stable in their absence because of favorable average curvature. Both modes are different from their usual resistive magnetohydrodynamic counterparts in their destabilization mechanism

Extracellular Trapping of Soil Contaminants by Root Border Cells: New Insights into Plant Defense

Directory of Open Access Journals (Sweden)

Martha C. Hawes

2016-01-01

Full Text Available Soil and water pollution by metals and other toxic chemicals is difficult to measure and control, and, as such, presents an ongoing global threat to sustainable agriculture and human health. Efforts to remove contaminants by plant-mediated pathways, or “phytoremediation”, though widely studied, have failed to yield consistent, predictable removal of biological and chemical contaminants. Emerging research has revealed that one major limitation to using plants to clean up the environment is that plants are programmed to protect themselves: Like white blood cells in animals, border cells released from plant root tips carry out an extracellular trapping process to neutralize threats and prevent injury to the host. Variability in border cell trapping has been found to be correlated with variation in sensitivity of roots to aluminum, and removal of border cell results in increased Al uptake into the root tip. Studies now have implicated border cells in responses of diverse plant roots to a range of heavy metals, including arsenic, copper, cadmium, lead, mercury, iron, and zinc. A better understanding of border cell extracellular traps and their role in preventing toxin uptake may facilitate efforts to use plants as a nondestructive approach to neutralize environmental threats.

Magnetic trapping of cold bromine atoms.

Science.gov (United States)

Rennick, C J; Lam, J; Doherty, W G; Softley, T P

2014-01-17

Magnetic trapping of bromine atoms at temperatures in the millikelvin regime is demonstrated for the first time. The atoms are produced by photodissociation of Br2 molecules in a molecular beam. The lab-frame velocity of Br atoms is controlled by the wavelength and polarization of the photodissociation laser. Careful selection of the wavelength results in one of the pair of atoms having sufficient velocity to exactly cancel that of the parent molecule, and it remains stationary in the lab frame. A trap is formed at the null point between two opposing neodymium permanent magnets. Dissociation of molecules at the field minimum results in the slowest fraction of photofragments remaining trapped. After the ballistic escape of the fastest atoms, the trapped slow atoms are lost only by elastic collisions with the chamber background gas. The measured loss rate is consistent with estimates of the total cross section for only those collisions transferring sufficient kinetic energy to overcome the trapping potential.

Metastable self-trapping of positrons in MgO

Science.gov (United States)

Monge, M. A.; Pareja, R.; González, R.; Chen, Y.

1997-01-01

Low-temperature positron annihilation measurements have been performed on MgO single crystals containing either cation or anion vacancies. The temperature dependence of the S parameter is explained in terms of metastable self-trapped positrons which thermally hop through the crystal lattice. The experimental results are analyzed using a three-state trapping model assuming transitions from both delocalized and self-trapped states to deep trapped states at vacancies. The energy level of the self-trapped state was determined to be (62+/-5) meV above the delocalized state. The activation enthalpy for the hopping process of self-trapped positrons appears to depend on the kind of defect present in the crystals.

Possibilities for achieving antihydrogen recombination and trapping using a nested Penning trap and a magnetic well

International Nuclear Information System (INIS)

Ordonez, C.A.; Dolliver, D.D.; Chang Yongbin; Correa, J. R.

2002-01-01

A theoretical study is presented regarding some possibilities for achieving antihydrogen recombination and trapping using a nested Penning trap and a magnetic well. The work reported consists of a review, an extension, and applications of the relevant knowledge base. A nested Penning trap produces a magnetic field, which provides plasma confinement perpendicular to the magnetic field, and an electric field associated with a nested-well potential profile. The nested-well potential profile provides plasma confinement parallel to the magnetic field for oppositely signed plasma species that can have overlapping confinement regions. A configuration is considered in which the electric field is applied in two regions of uniform magnetic field that reside on opposite sides of a magnetic well region. The electric field confines overlapping positron and antiproton plasmas, which thread the magnetic well region. The magnetic well region would serve to trap a fraction of any antihydrogen atoms that are formed. Two different methods are considered for achieving overlap of positron and antiproton plasmas. For each, a set of conditions is predicted for achieving antihydrogen recombination and trapping. Although the study reported specifically considers simultaneous confinement of positron and antiproton plasmas in nested Penning traps, much of the information presented is also relevant to the prospect of merging other pairs of oppositely signed plasmas (e.g., electron and positron plasmas)

Geometric light trapping with a V-trap for efficient organic solar cells

KAUST Repository

Kim, Soo Jin

2013-03-14

The efficiency of today’s most efficient organic solar cells is primarily limited by the ability of the active layer to absorb all the sunlight. While internal quantum efficiencies exceeding 90% are common, the external quantum efficiency rarely exceeds 70%. Light trapping techniques that increase the ability of a given active layer to absorb light are common in inorganic solar cells but have only been applied to organic solar cells with limited success. Here, we analyze the light trapping mechanism for a cell with a V-shape substrate configuration and demonstrate significantly improved photon absorption in an 5.3%-efficient PCDTBT:PC70BM bulk heterojunction polymer solar cell. The measured short circuit current density improves by 29%, in agreement with model predictions, and the power conversion efficiency increases to 7.2%, a 35% improvement over the performance in the absence of a light trap.

Appalachian basin oil and natural gas: stratigraphic framework, total petroleum systems, and estimated ultimate recovery: Chapter C.1 in Coal and petroleum resources in the Appalachian basin: distribution, geologic framework, and geochemical character

Science.gov (United States)

Ryder, Robert T.; Milici, Robert C.; Swezey, Christopher S.; Trippi, Michael H.; Ruppert, Leslie F.; Ryder, Robert T.

2014-01-01

The most recent U.S. Geological Survey (USGS) assessment of undiscovered oil and gas resources of the Appalachian basin was completed in 2002 (Milici and others, 2003). This assessment was based on the total petroleum system (TPS), a concept introduced by Magoon and Dow (1994) and developed during subsequent studies such as those by the U.S. Geological Survey World Energy Assessment Team (2000) and by Biteau and others (2003a,b). Each TPS is based on specific geologic elements that include source rocks, traps and seals, reservoir rocks, and the generation and migration of hydrocarbons. This chapter identifies the TPSs defined in the 2002 Appalachian basin oil and gas assessment and places them in the context of the stratigraphic framework associated with regional geologic cross sections D–D′ (Ryder and others, 2009, which was re-released in this volume, chap. E.4.1) and E–E′ (Ryder and others, 2008, which was re-released in this volume, chap. E.4.2). Furthermore, the chapter presents a recent estimate of the ultimate recoverable oil and natural gas in the basin.

Trapping technology for gaseous fission products from voloxidation process

Energy Technology Data Exchange (ETDEWEB)

Shin, Jin Myeong; Park, J. J.; Park, G. I.; Jung, I. H.; Lee, H. H.; Kim, G. H.; Yang, M. S

2005-05-15

The objective of this report is to review the different technologies for trapping the gaseous wastes containing Cs, Ru, Tc, {sup 14}C, Kr, Xe, I and {sup 3}H from a voloxidation process. Based on literature reviews and KAERI's experimental results on the gaseous fission products trapping, appropriate trapping method for each fission product has been selected considering process reliability, simplicity, decontamination factor, availability, and disposal. Specifically, the most promising trapping method for each fission product has been proposed for the development of the INL off-gas trapping system. A fly ash filter is proposed as a trapping media for a cesium trapping unit. In addition, a calcium filter is proposed as a trapping media for ruthenium, technetium, and {sup 14}C trapping unit. In case of I trapping unit, AgX is proposed. For Kr and Xe, adsorption on solid is proposed. SDBC (Styrene Divinyl Benzene Copolymer) is also proposed as a conversion media to HTO for {sup 3}H. This report will be used as a useful means for analyzing the known trapping technologies and help selecting the appropriate trapping methods for trapping volatile and semi-volatile fission products, long-lived fission products, and major heat sources generated from a voloxidation process. It can also be used to design an off-gas treatment system.

Vapour trap development and operational experience

International Nuclear Information System (INIS)

Jansing, W.; Kirchner, G.; Menck, J.

1977-01-01

Sodium aerosols have the unpleasant characteristic that they deposit at places with low temperature level. This effect can be utilized when sodium aerosols are to be trapped at places which are determined beforehand. Thus vapour traps were developed which can filter sodium vapour from the cover gas. By this means the necessity was eliminated to heat all gas lines and gas systems with trace heaters just as all sodium lines are heated. It was of special interest for the INTERATOM to develop vapour traps which must not be changed or cleaned after a certain limited operating period. The vapour traps were supposed to enable maintenance free operation, i.e. they were to operate 'self cleaning'

Palaeolithic/Mesolithic stratigraphic sequences at Údolí samoty and Janova zátoka rock shelters (Northern Bohemia)

Czech Academy of Sciences Publication Activity Database

Svoboda, Jiří; Novák, J.; Novák, Martin; Sázelová, S.; Demek, J.; Hladilová, Š.; Peša, V.

2013-01-01

Roč. 43, č. 4 (2013), s. 469-488 ISSN 0342-734X R&D Projects: GA ČR GA13-08169S Institutional support: RVO:68081758 Keywords : Pleistocene/Holocene boundary * Northern Bohemia * stratigraphic sequences * rock shelters * environment Subject RIV: AC - Archeology, Anthropology, Ethnology

Influence of local capillary trapping on containment system effectiveness

Energy Technology Data Exchange (ETDEWEB)

Bryant, Steven [University Of Texas At Austin, Austin, TX (United States). Center for Petroleum and Geosystems Engineering

2014-03-31

implications for GCS. The first is that LCT can retain a significant fraction of the CO₂ stored in a reservoir – above and beyond the residual saturation -- if the overlying seal were to fail. Thus frameworks for risk assessment should be extended to account for LCT. The second implication is that compared to pressure driven flow in reservoirs, CO₂ migration and trapping behave in a qualitatively different manner in heterogeneous reservoirs when buoyancy is the dominant driving force for flow. Thus simulations of GCS that neglect capillary heterogeneity will fail to capture important features of the CO₂ plume. While commercial reservoir simulation software can account for fine scale capillary heterogeneity, it has not been designed to work efficiently with such domains, and no simulators can handle fine-scale resolution throughout the reservoir. A possible way to upscale the migration and trapping is to apply an “effective residual saturation” to coarse-scale grids. While the extent of overall immobilization can be correlated in this way, all coarser grids failed to capture the distance traveled by the migrating CO₂ for large gravity number. Thus it remains unclear how best to account for LCT in the routine simulation work-flow that will be needed for large-scale GCS. Alternatives meriting investigation include streamline methods, reduced-physics proxies (e.g. particle tracking), and biased invasion percolation algorithms, which are based on precisely the capillary heterogeneity essential for LCT.

Flux trapping in superconducting cavities

International Nuclear Information System (INIS)

Vallet, C.; Bolore, M.; Bonin, B.; Charrier, J.P.; Daillant, B.; Gratadour, J.; Koechlin, F.; Safa, H.

1992-01-01

The flux trapped in various field cooled Nb and Pb samples has been measured. For ambient fields smaller than 3 Gauss, 100% of the flux is trapped. The consequences of this result on the behavior of superconducting RF cavities are discussed. (author) 12 refs.; 2 figs

Achieving Translationally Invariant Trapped Ion Rings

Science.gov (United States)

Urban, Erik; Li, Hao-Kun; Noel, Crystal; Hemmerling, Boerge; Zhang, Xiang; Haeffner, Hartmut

2017-04-01

We present the design and implementation of a novel surface ion trap design in a ring configuration. By eliminating the need for wire bonds through the use of electrical vias and using a rotationally invariant electrode configuration, we have realized a trap that is able to trap up to 20 ions in a ring geometry 45um in diameter, 400um above the trap surface. This large trapping height to ring diameter ratio allows for global addressing of the ring with both lasers and electric fields in the chamber, thereby increasing our ability to control the ring as a whole. Applying compensating electric fields, we measure very low tangential trap frequencies (less than 20kHz) corresponding to rotational barriers down to 4mK. This measurement is currently limited by the temperature of the ions but extrapolation indicates the barrier can be reduced much further with more advanced cooling techniques. Finally, we show that we are able to reduce this energy barrier sufficiently such that the ions are able to overcome it either through thermal motion or rotational motion and delocalize over the full extent of the ring. This work was funded by the Keck Foundation and the NSF.

Mini ion trap mass spectrometer

Science.gov (United States)

Dietrich, D.D.; Keville, R.F.

1995-09-19

An ion trap is described which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10{sup 9} and commercial mass spectrometers requiring 10{sup 4} ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products. 10 figs.

Use of stratigraphic models as soft information to constrain stochastic modeling of rock properties: Development of the GSLIB-Lynx integration module

International Nuclear Information System (INIS)

Cromer, M.V.; Rautman, C.A.

1995-10-01

Rock properties in volcanic units at Yucca Mountain are controlled largely by relatively deterministic geologic processes related to the emplacement, cooling, and alteration history of the tuffaceous lithologic sequence. Differences in the lithologic character of the rocks have been used to subdivide the rock sequence into stratigraphic units, and the deterministic nature of the processes responsible for the character of the different units can be used to infer the rock material properties likely to exist in unsampled regions. This report proposes a quantitative, theoretically justified method of integrating interpretive geometric models, showing the three-dimensional distribution of different stratigraphic units, with numerical stochastic simulation techniques drawn from geostatistics. This integration of soft, constraining geologic information with hard, quantitative measurements of various material properties can produce geologically reasonable, spatially correlated models of rock properties that are free from stochastic artifacts for use in subsequent physical-process modeling, such as the numerical representation of ground-water flow and radionuclide transport. Prototype modeling conducted using the GSLIB-Lynx Integration Module computer program, known as GLINTMOD, has successfully demonstrated the proposed integration technique. The method involves the selection of stratigraphic-unit-specific material-property expected values that are then used to constrain the probability function from which a material property of interest at an unsampled location is simulated

The stratigraphic imprint of a mid-Telychian (Llandovery, Early Silurian glaciation on far-field shallow-water carbonates, Anticosti Island, Eastern Canada

Directory of Open Access Journals (Sweden)

François Clayer

2014-12-01

Full Text Available The near-field stratigraphic record of the Early Silurian glaciations is well documented in the literature. Data from far-field areas are, however, sparse. One of the best far-field stratigraphic records of these Llandovery glaciations is exposed on Anticosti Island in eastern Canada. Eight shallow-water paleotropical facies are present close to the mid-Telychian Jupiter–Chicotte formational boundary along the south-central coast of Anticosti Island. These can be grouped into three facies associations that include, from bottom to top: a carbonate facies association (FA-1, a mixed siliciclastic and carbonate facies association (FA-2 and an encrinitic facies association (FA-3. These mid- to outer-ramp strata represent deposition mostly from episodic, high-energy storm events as evidenced by their sharp bases, hummocky cross-stratification, large wave ripples, gutter casts and wave-enhanced sediment gravity flow deposits. Superimposed on a long-term regressive trend, one main transgressive–regressive (TR sequence and four meter-scale TR cycles are evident, indicating a multi-order stratigraphic framework developed under the influence of glacio-eustasy. The Jupiter–Chicotte formational boundary, a regional discontinuity surface caused by a forced regression, corresponds to the onset of a far-field mid-Telychian glaciation.

Ion bunch stacking in a Penning trap after purification in an electrostatic mirror trap

CERN Document Server

Rosenbusch, M; Blaum, K; Borgmann, Ch; Kreim, S; Lunney, D; Manea, V; Schweikhard, L; Wienholtz, F; Wolf, R N

2014-01-01

The success of many measurements in analytical mass spectrometry as well as in precision mass determinations for atomic and nuclear physics is handicapped when the ion sources deliver ``contaminations'', i.e., unwanted ions of masses similar to those of the ions of interest. In particular, in ion-trapping devices, large amounts of contaminant ions result in significant systematic errors-if the measurements are possible at all. We present a solution for such cases: The ions from a quasi-continuous source are bunched in a linear radio-frequency-quadrupole ion trap, separated by a multi-reflection time-of-flight section followed by a Bradbury-Nielsen gate, and then captured in a Penning trap. Buffer-gas cooling is used to damp the ion motion in the latter, which allows a repeated opening of the Penning trap for a stacking of mass-selected ion bunches. Proof-of-principle demonstrations have been performed with the ISOLTRAP setup at ISOLDE/CERN, both with Cs-133(+) ions from an off-line ion source and by applicati...

Ripple Trap

Science.gov (United States)

2006-01-01

3 April 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the margin of a lava flow on a cratered plain in the Athabasca Vallis region of Mars. Remarkably, the cratered plain in this scene is essentially free of bright, windblown ripples. Conversely, the lava flow apparently acted as a trap for windblown materials, illustrated by the presence of the light-toned, wave-like texture over much of the flow. That the lava flow surface trapped windblown sand and granules better than the cratered plain indicates that the flow surface has a rougher texture at a scale too small to resolve in this image. Location near: 10.7oN, 204.5oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Winter

Density of Trap States and Auger-mediated Electron Trapping in CdTe Quantum-Dot Solids

NARCIS (Netherlands)

Boehme, Simon C.; Mikel Azpiroz, Jon; Aulin, Yaroslav V.; Grozema, Ferdinand C.; Vanmaekelbergh, Daniel; Siebbeles, Laurens D. A.; Infante, Ivan; Houtepen, Arjan J.

Charge trapping is an ubiquitous process in colloidal quantum-dot solids and a major limitation to the efficiency of quantum dot based devices such as solar cells, LEDs, and thermoelectrics. Although empirical approaches led to a reduction of trapping and thereby efficiency enhancements, the exact

Density of trap states and Auger-mediated electron trapping in CdTe quantum-dot solids

NARCIS (Netherlands)

Boehme, Simon C.; Azpiroz, Jon Mikel; Aulin, Yaroslav V.; Grozema, Ferdinand C.; Vanmaekelbergh, Daniël; Siebbeles, Laurens D A; Infante, Ivan; Houtepen, Arjan J.

2015-01-01

Charge trapping is an ubiquitous process in colloidal quantum-dot solids and a major limitation to the efficiency of quantum dot based devices such as solar cells, LEDs, and thermoelectrics. Although empirical approaches led to a reduction of trapping and thereby efficiency enhancements, the exact

Deuterium transport and trapping in polycrystalline tungsten

International Nuclear Information System (INIS)

Anderl, R.A.; Holland, D.F.; Longhurst, G.R.; Pawelko, R.J.; Trybus, C.L.; Sellers, C.H.

1992-01-01

This paper reports that deuterium permeation studies for polycrystalline tungsten foil have been conducted to provide data for estimating tritium transport and trapping in tungsten-clad divertors proposed for advanced fusion-reactor concepts. Based on a detailed transmission electron microscopy (TEM) microstructural characterization of the specimen material and on analyses of permeation data measured at temperatures ranging form 610 to 823 K for unannealed and annealed tungsten foil (25 μm thick), the authors note the following key results: deuterium transport in tungsten foil is dominated by extensive trapping that varies inversely with prior anneal temperatures of the foil material, the reduction in the trapped fraction correlates with a corresponding elimination of a high density of dislocations in cell-wall structures introduced during the foil fabrication process, trapping behavior in these foils can be modelled using trap energies between 1.3 eV and 1.5 eV and trap densities ranging from 1 x 10 -5 atom fraction

Ion trap device

Science.gov (United States)

Ibrahim, Yehia M.; Smith, Richard D.

2016-01-26

An ion trap device is disclosed. The device includes a series of electrodes that define an ion flow path. A radio frequency (RF) field is applied to the series of electrodes such that each electrode is phase shifted approximately 180 degrees from an adjacent electrode. A DC voltage is superimposed with the RF field to create a DC gradient to drive ions in the direction of the gradient. A second RF field or DC voltage is applied to selectively trap and release the ions from the device. Further, the device may be gridless and utilized at high pressure.

21 CFR 868.5995 - Tee drain (water trap).

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Tee drain (water trap). 868.5995 Section 868.5995...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5995 Tee drain (water trap). (a) Identification. A tee drain (water trap) is a device intended to trap and drain water that collects in ventilator...

(Anti)hydrogen recombination studies in a nested Penning trap

International Nuclear Information System (INIS)

Quint, W.; Kaiser, R.; Hall, D.; Gabrielse, G.

1993-01-01

Extremely cold antiprotons, stored in Penning trap at 4 K, open the way toward the production and study of cold antihydrogen. We have begun experimentally investigating the possibility to recombine cold positrons and antiprotons within nested Penning traps. Trap potentials are adjusted to allow cold trapped protons (and positive helium ions) to pass through cold trapped electrons. Electrons, protons and ions are counted by ejecting them to a cold channel plate and by nondestructive radiofrequency techniques. The effect of the space charge of one trapped species upon another trapped species passing through is clearly observed. (orig.)

Governance and the making and breaking of social-ecological traps

Directory of Open Access Journals (Sweden)

Dana M. Baker

2018-03-01

Full Text Available Many countries in sub-Saharan Africa have areas of significant ecological importance that overlap with pressing development needs and high levels of natural resource dependence. This makes the design of effective natural resource governance and management systems both challenging and critical. In Ghana, this challenge is made more complex by the necessity of connecting formal, state-led systems of governance with Ghana's informal governance systems through which customary authorities exert considerable control over land and resources. We present findings from two multimethod research projects in two regions of Ghana that have significant issues related to resource exploitation and that have experienced extensive management interventions. The goals of the research were to characterize the social-ecological traps from a local perspective, to describe how governance and management structures interact with and relate to those traps, and to discuss the strategies used and challenges encountered when community-based natural resource management initiatives seek to reverse persistent social-ecological traps. In both case studies, participants described persistent cycles of resource dependence, overexploitation, and unsustainable land-use practices, which are exacerbated by illegal logging, intensive agricultural development, and population growth. Findings highlight how natural resource management is constrained by a lack of capacity to implement and enforce state policies, ongoing tension between customary and state institutions, and ambiguity regarding management responsibility and resource tenure. Interventions included targeted governance reform that centred on improving linkages between customary and state institutions, new and nonlocal actors, and complementary investments in capacity building and training. We conclude with a discussion of implications for the design of effective natural resource governance regimes in Ghana and beyond.

Stability of Trapped Electrons in SiO(2)

International Nuclear Information System (INIS)

Fleetwood, D.M.; Winokur, P.S.

1999-01-01

Thermally stimulated current and capacitance voltage methods are used to investigate the thermal stability of trapped electrons associated with radiation-induced trapped positive charge in metal-oxide-semiconductor capacitors. The density of deeply trapped electrons in radiation-hardened 45 nm oxides exceeds that of shallow electrons by a factor of ∼3 after radiation exposure, and by up to a factor of 10 or more during biased annealing. Shallow electron traps anneal faster than deep traps, and seem to be at least qualitatively consistent with the model of Lelis et al. Deeper traps maybe part of a fundamentally distinct dipole complex, and/or have shifted energy levels that inhibit charge exchange with the Si

An Open Standard for Camera Trap Data

NARCIS (Netherlands)

Forrester, Tavis; O'Brien, Tim; Fegraus, Eric; Jansen, P.A.; Palmer, Jonathan; Kays, Roland; Ahumada, Jorge; Stern, Beth; McShea, William

2016-01-01

Camera traps that capture photos of animals are a valuable tool for monitoring biodiversity. The use of camera traps is rapidly increasing and there is an urgent need for standardization to facilitate data management, reporting and data sharing. Here we offer the Camera Trap Metadata Standard as an

Neoproterozoic–Cambrian stratigraphic framework of the Anti-Atlas and Ouzellagh promontory (High Atlas), Morocco

Science.gov (United States)

Alvaro, Jose Javier; Benziane, Fouad; Thomas, Robert; Walsh, Gregory J.; Yazidi, Abdelaziz

2014-01-01

In the last two decades, great progress has been made in the geochronological, chrono- and chemostratigraphic control of the Neoproterozoic and Cambrian from the Anti-Atlas Ranges and the Ouzellagh promontory (High Atlas). As a result, the Neoproterozoic is lithostratigraphically subdivided into: (i) the Lkest-Taghdout Group (broadly interpreted at c. 800–690 Ma) representative of rift-to-passive margin conditions on the northern West African craton; (ii) the Iriri (c. 760–740 Ma), Bou Azzer (c. 762–697 Ma) and Saghro (c. 760?–610 Ma) groups, the overlying Anezi, Bou Salda, Dadès and Tiddiline formations localized in fault-grabens, and the Ouarzazate Supergroup (c. 615–548 Ma), which form a succession of volcanosedimentary complexes recording the onset of the Pan-African orogeny and its aftermath; and (iii) the Taroudant (the Ediacaran–Cambrian boundary lying in the Tifnout Member of the Adoudou Formation), Tata, Feijas Internes and Tabanite groups that have recorded development of the late Ediacaran–Cambrian Atlas Rift. Recent discussions of Moroccan strata to select new global GSSPs by the International Subcommissions on Ediacaran and Cambrian Stratigraphy have raised the stratigraphic interest in this region. A revised and updated stratigraphic framework is proposed here to assist the tasks of both subcommissions and to fuel future discussions focused on different geological aspects of the Neoproterozoic–Cambrian time span.

Spectral and stratigraphic mapping of hydrated minerals associated with interior layered deposits near the southern wall of Melas Chasma, Mars

Science.gov (United States)

Liu, Yang; Goudge, Timothy A.; Catalano, Jeffrey G.; Wang, Alian

2018-03-01

Orbital remote sensing data acquired from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) onboard Mars Reconnaissance Orbiter (MRO), in conjunction with other datasets, are used to perform detailed spectral and stratigraphic analyses over a portion of south Melas Chasma, Mars. The Discrete Ordinate Radiative Transfer (DISORT) model is used to retrieve atmospherically corrected single scattering albedos from CRISM I/F data for mineral identification. A sequence of interbedded poly- and monohydrated sulfates associated with interior layered deposits (ILDs) is identified and mapped. Analyses from laboratory experiments and spectral unmixing of CRISM hyperspectral data support the hypothesis of precipitation and dehydration of multiple inputs of complex Mg-Ca-Fe-SO4-Cl brines. In this scenario, the early precipitated Mg sulfates could dehydrate into monohydrated sulfate due to catalytic effects, and the later-precipitated Mg sulfates from the late-stage "clean" brine could terminate their dehydration at mid-degree of hydration to form a polyhydrated sulfate layer due to depletion of the catalytic species (e.g., Ca, Fe, and Cl). Distinct jarosite-bearing units are identified stratigraphically above the hydrated sulfate deposits. These are hypothesized to have formed either by oxidation of a fluid containing Fe(II) and SO4, or by leaching of soluble phases from precursor intermixed jarosite-Mg sulfate units that may have formed during the later stages of deposition of the hydrated sulfate sequence. Results from stratigraphic analysis of the ILDs show that the layers have a consistent northward dip towards the interior of the Melas Chasma basin, a mean dip angle of ∼6°, and neighboring strata that are approximately parallel. These strata are interpreted as initially sub-horizontal layers of a subaqueous, sedimentary evaporite deposits that underwent post-depositional tilting from slumping into the Melas Chasma basin. The interbedded hydrated sulfate

A Computer Model of Insect Traps in a Landscape

Science.gov (United States)

Manoukis, Nicholas C.; Hall, Brian; Geib, Scott M.

2014-11-01

Attractant-based trap networks are important elements of invasive insect detection, pest control, and basic research programs. We present a landscape-level, spatially explicit model of trap networks, focused on detection, that incorporates variable attractiveness of traps and a movement model for insect dispersion. We describe the model and validate its behavior using field trap data on networks targeting two species, Ceratitis capitata and Anoplophora glabripennis. Our model will assist efforts to optimize trap networks by 1) introducing an accessible and realistic mathematical characterization of the operation of a single trap that lends itself easily to parametrization via field experiments and 2) allowing direct quantification and comparison of sensitivity between trap networks. Results from the two case studies indicate that the relationship between number of traps and their spatial distribution and capture probability under the model is qualitatively dependent on the attractiveness of the traps, a result with important practical consequences.

Fast and slow border traps in MOS devices

International Nuclear Information System (INIS)

Fleetwood, D.M.

1996-01-01

Convergent lines of evidence are reviewed which show that near-interfacial oxide traps (border traps) that exchange charge with the Si can strongly affect the performance, radiation response, and long-term reliability of MOS devices. Observable effects of border traps include capacitance-voltage (C-V) hysteresis, enhanced l/f noise, compensation of trapped holes, and increased thermally stimulated current in MOS capacitors. Effects of faster (switching times between ∼10 -6 s and ∼1 s) and slower (switching times greater than ∼1 s) border traps have been resolved via a dual-transistor technique. In conjunction with studies of MOS electrical response, electron paramagnetic resonance and spin dependent recombination studies suggest that E' defects (trivalent Si centers in SiO 2 associated with O vacancies) can function as border traps in MOS devices exposed to ionizing radiation or high-field stress. Hydrogen-related centers may also be border traps

A reservoir trap for antiprotons

CERN Document Server

Smorra, Christian; Franke, Kurt; Nagahama, Hiroki; Schneider, Georg; Higuchi, Takashi; Van Gorp, Simon; Blaum, Klaus; Matsuda, Yasuyuki; Quint, Wolfgang; Walz, Jochen; Yamazaki, Yasunori; Ulmer, Stefan

2015-01-01

We have developed techniques to extract arbitrary fractions of antiprotons from an accumulated reservoir, and to inject them into a Penning-trap system for high-precision measurements. In our trap-system antiproton storage times > 1.08 years are estimated. The device is fail-safe against power-cuts of up to 10 hours. This makes our planned comparisons of the fundamental properties of protons and antiprotons independent from accelerator cycles, and will enable us to perform experiments during long accelerator shutdown periods when background magnetic noise is low. The demonstrated scheme has the potential to be applied in many other precision Penning trap experiments dealing with exotic particles.

Active stabilization of ion trap radiofrequency potentials

Energy Technology Data Exchange (ETDEWEB)

Johnson, K. G.; Wong-Campos, J. D.; Restelli, A.; Landsman, K. A.; Neyenhuis, B.; Mizrahi, J.; Monroe, C. [Joint Quantum Institute and University of Maryland Department of Physics, College Park, Maryland 20742 (United States)

2016-05-15

We actively stabilize the harmonic oscillation frequency of a laser-cooled atomic ion confined in a radiofrequency (rf) Paul trap by sampling and rectifying the high voltage rf applied to the trap electrodes. We are able to stabilize the 1 MHz atomic oscillation frequency to be better than 10 Hz or 10 ppm. This represents a suppression of ambient noise on the rf circuit by 34 dB. This technique could impact the sensitivity of ion trap mass spectrometry and the fidelity of quantum operations in ion trap quantum information applications.

Laser induced fluorescence of trapped molecular ions

Energy Technology Data Exchange (ETDEWEB)

Grieman, F.J.

1979-10-01

An experimental apparatus for obtaining the optical spectra of molecular ions is described. The experimental technique includes the use of three dimensional ion trapping, laser induced fluorescence, and gated photon counting methods. The ions, which are produced by electron impact, are confined in a radio-frequency quadrupole ion trap of cylindrical design. Because the quadrupole ion trap allows mass selection of the molecular ion desired for study, the analysis of the spectra obtained is greatly simplified. The ion trap also confines the ions to a region easily probed by a laser beam. 18 references.

Laser induced fluorescence of trapped molecular ions

International Nuclear Information System (INIS)

Grieman, F.J.

1979-10-01

An experimental apparatus for obtaining the optical spectra of molecular ions is described. The experimental technique includes the use of three dimensional ion trapping, laser induced fluorescence, and gated photon counting methods. The ions, which are produced by electron impact, are confined in a radio-frequency quadrupole ion trap of cylindrical design. Because the quadrupole ion trap allows mass selection of the molecular ion desired for study, the analysis of the spectra obtained is greatly simplified. The ion trap also confines the ions to a region easily probed by a laser beam. 18 references

Acoustic trapping in bubble-bounded micro-cavities

Science.gov (United States)

O'Mahoney, P.; McDougall, C.; Glynne-Jones, P.; MacDonald, M. P.

2016-12-01

We present a method for controllably producing longitudinal acoustic trapping sites inside microfluidic channels. Air bubbles are injected into a micro-capillary to create bubble-bounded `micro-cavities'. A cavity mode is formed that shows controlled longitudinal acoustic trapping between the two air/water interfaces along with the levitation to the centre of the channel that one would expect from a lower order lateral mode. 7 μm and 10 μm microspheres are trapped at the discrete acoustic trapping sites in these micro-cavities.We show this for several lengths of micro-cavity.

Ichnology applied to sequence stratigraphic analysis of Siluro-Devonian mud-dominated shelf deposits, Paraná Basin, Brazil

Science.gov (United States)

Sedorko, Daniel; Netto, Renata G.; Savrda, Charles E.

2018-04-01

Previous studies of the Paraná Supersequence (Furnas and Ponta Grossa formations) of the Paraná Basin in southern Brazil have yielded disparate sequence stratigraphic interpretations. An integrated sedimentological, paleontological, and ichnological model was created to establish a refined sequence stratigraphic framework for this succession, focusing on the Ponta Grossa Formation. Twenty-nine ichnotaxa are recognized in the Ponta Grossa Formation, recurring assemblages of which define five trace fossil suites that represent various expressions of the Skolithos, Glossifungites and Cruziana ichnofacies. Physical sedimentologic characteristics and associated softground ichnofacies provide the basis for recognizing seven facies that reflect a passive relationship to bathymetric gradients from shallow marine (shoreface) to offshore deposition. The vertical distribution of facies provides the basis for dividing the Ponta Grossa Formation into three major (3rd-order) depositional sequences- Siluro-Devonian and Devonian I and II-each containing a record of three to seven higher-order relative sea-level cycles. Major sequence boundaries, commonly coinciding with hiatuses recognized from previously published biostratigraphic data, are locally marked by firmground Glossifungites Ichnofacies associated with submarine erosion. Maximum transgressive horizons are prominently marked by unbioturbated or weakly bioturbated black shales. By integrating observations of the Ponta Grossa Formation with those recently made on the underlying marginal- to shallow-marine Furnas Formation, the entire Paraná Supersequence can be divided into four disconformity-bound sequences: a Lower Silurian (Llandovery-Wenlock) sequence, corresponding to lower and middle units of the Furnas; a Siluro-Devonian sequence (?Pridoli-Early Emsian), and Devonian sequences I (Late Emsian-Late Eifelian) and II (Late Eifelian-Early Givetian). Stratigraphic positions of sequence boundaries generally coincide with

Microfabricated Microwave-Integrated Surface Ion Trap

Science.gov (United States)

Revelle, Melissa C.; Blain, Matthew G.; Haltli, Raymond A.; Hollowell, Andrew E.; Nordquist, Christopher D.; Maunz, Peter

2017-04-01

Quantum information processing holds the key to solving computational problems that are intractable with classical computers. Trapped ions are a physical realization of a quantum information system in which qubits are encoded in hyperfine energy states. Coupling the qubit states to ion motion, as needed for two-qubit gates, is typically accomplished using Raman laser beams. Alternatively, this coupling can be achieved with strong microwave gradient fields. While microwave radiation is easier to control than a laser, it is challenging to precisely engineer the radiated microwave field. Taking advantage of Sandia's microfabrication techniques, we created a surface ion trap with integrated microwave electrodes with sub-wavelength dimensions. This multi-layered device permits co-location of the microwave antennae and the ion trap electrodes to create localized microwave gradient fields and necessary trapping fields. Here, we characterize the trap design and present simulated microwave performance with progress towards experimental results. This research was funded, in part, by the Office of the Director of National Intelligence (ODNI), Intelligence Advanced Research Projects Activity (IARPA).

The use of handheld radiometry for the identification of stratigraphic characteristics of Paraiba Basin units

International Nuclear Information System (INIS)

Souza, Ebenezer Moreno de; Villar, Heldio Pereira; Lima, Ricardo de Andrade; Lima Filho, Mario

2000-01-01

A study on the use of radiometric techniques for the identification of stratigraphic characteristics of Paraiba Basin units was carried out with handheld instrumentation. The area chosen ran from north Pernambuco to south Paraiba. The presence of radioactive material had been previously determined. For this work a portable scintillometer was fixed to the door of a vehicle, on the outside, with the probe directed downwards. Background radiation was measured as 40 cps (counts per second). The scintillometer has an alarm which sounds whenever the measured count rate rises above a pre-established figure, 100 cps in the present case. Monitoring then proceeded manually. In sites where the count rate was much higher than 100 cps, the probe was lowered to the soil surface. Local coordinates were obtained by GPS. Therefore, an isoradioactivity map of the area could be drawn. The comparison between this map and local geological charts showed significant correlation between observed count rates and geologic formations. Low count rates were indicative of the Barreiras formation, whereas the highest rates were obtained for the Gramame formation (with urano-phosphatic lythotypes). It is concluded that handheld radiometry is a useful tool in geological charting, is special in areas where stratigraphic units have been masked by environmental changes and human activities. (author)

Laser spectroscopy with an electrostatic ConeTrap

Energy Technology Data Exchange (ETDEWEB)

Kelly, S., E-mail: sam.kelly@postgrad.manchester.ac.uk; Campbell, P. [University of Manchester, Nuclear Physics Group, Schuster Laboratory, Brunswick Street (United Kingdom); Cheal, B., E-mail: Bradley.Cheal@Liverpool.ac.uk [University of Liverpool, Oliver Lodge Laboratory (United Kingdom); Eronen, T.; Geldhof, S.; Jokinen, A.; Moore, I. D.; Penttilä, H.; Pohjalainen, I.; Rinta-Antila, S.; Sonnenschein, V.; Voss, A. [JYFL, University of Jyväskylä (Finland)

2017-11-15

A compact electrostatic trap has been designed and installed as part of the recent upgrades to the IGISOL IV facility. The ConeTrap provides an in vacuo optical pumping site for low energy (800 eV) ionic ensembles available for interaction periods of 10-100 ms. At present, 6.7(3) % of injected mass A=98 ions can be trapped, stored for 5 ms, extracted and transported to a laser-ion interaction region. This fraction represents those ions for which no perturbation to total energy or energy spread is observed. Proposed enhancements to the trap are designed to improve the trapping efficiency by up to a factor of 5. Differential pumping and reduction in background pressure below the present 10{sup −6} mbar will extend storage times beyond 100 ms.

Trapped surfaces in spherical stars

International Nuclear Information System (INIS)

Bizon, P.; Malec, E.; O'Murchadha, N.

1988-01-01

We give necessary and sufficient conditions for the existence of trapped surfaces in spherically symmetric spacetimes. These conditions show that the formation of trapped surfaces depends on both the degree of concentration and the average flow of the matter. The result can be considered as a partial validation of the cosmic-censorship hypothesis

Geological Identification of Seismic Source at Opak Fault Based on Stratigraphic Sections of the Southern Mountains

Directory of Open Access Journals (Sweden)

Hita Pandita

2016-08-01

Full Text Available Earthquake is one of the unpredicted natural disasters on our earth. Despite of the absence of high-accuracy method to precisely predict the occurrence of earthquake, numerous studies have been carried out by seismologists to find it. One of the efforts to address the vulnerability of a region to earthquakes is by recognizing the type of rock as the source of the earthquake. Opak Fault is an active fault which was thought to be the source of earthquakes in Yogyakarta and adjacent areas. This study aimed to determine the seismic source types of rocks in Yogyakarta and adjacent areas. The methods were by measuring stratigraphic sections and the layer thickness in the western part of Southern Mountains. Field study was done in 6 (six research sites. Results of stratigraphic measurement indicated the sedimentary rocks in the Southern Mountains was 3.823 km in thick, while the bedrock was more than 1.042 km in thick. Based on the result, the rock types as the seismic source were thought to originate from the continental crust rocks formed of granite and metamorphic complex.

Quantum information processing with trapped ions

International Nuclear Information System (INIS)

Haeffner, H.; Haensel, W.; Rapol, U.; Koerber, T.; Benhelm, J.; Riebe, M.; Chek-al-Kar, D.; Schmidt-Kaler, F.; Becher, C.; Roos, C.; Blatt, R.

2005-01-01

Single Ca + ions and crystals of Ca + ions are confined in a linear Paul trap and are investigated for quantum information processing. Here we report on recent experimental advancements towards a quantum computer with such a system. Laser-cooled trapped ions are ideally suited systems for the investigation and implementation of quantum information processing as one can gain almost complete control over their internal and external degrees of freedom. The combination of a Paul type ion trap with laser cooling leads to unique properties of trapped cold ions, such as control of the motional state down to the zero-point of the trapping potential, a high degree of isolation from the environment and thus a very long time available for manipulations and interactions at the quantum level. The very same properties make single trapped atoms and ions well suited for storing quantum information in long lived internal states, e.g. by encoding a quantum bit (qubit) of information within the coherent superposition of the S 1/2 ground state and the metastable D 5/2 excited state of Ca + . Recently we have achieved the implementation of simple algorithms with up to 3 qubits on an ion-trap quantum computer. We will report on methods to implement single qubit rotations, the realization of a two-qubit universal quantum gate (Cirac-Zoller CNOT-gate), the deterministic generation of multi-particle entangled states (GHZ- and W-states), their full tomographic reconstruction, the realization of deterministic quantum teleportation, its quantum process tomography and the encoding of quantum information in decoherence-free subspaces with coherence times exceeding 20 seconds. (author)

The Use of Camera Traps in Wildlife

Directory of Open Access Journals (Sweden)

Yasin Uçarlı

2013-11-01

Full Text Available Camera traps are increasingly used in the abundance and density estimates of wildlife species. Camera traps are very good alternative for direct observation in case, particularly, steep terrain, dense vegetation covered areas or nocturnal species. The main reason for the use of camera traps is eliminated that the economic, personnel and time loss in a continuous manner at the same time in different points. Camera traps, motion and heat sensitive, can take a photo or video according to the models. Crossover points and feeding or mating areas of the focal species are addressed as a priority camera trap set locations. The population size can be finding out by the images combined with Capture-Recapture methods. The population density came out the population size divided to effective sampling area size. Mating and breeding season, habitat choice, group structures and survival rates of the focal species can be achieved from the images. Camera traps are very useful to obtain the necessary data about the particularly mysterious species with economically in planning and conservation efforts.

Tightly confined atoms in optical dipole traps

International Nuclear Information System (INIS)

Schulz, M.

2002-12-01

This thesis reports on the design and setup of a new atom trap apparatus, which is developed to confine few rubidium atoms in ultrahigh vacuum and make them available for controlled manipulations. To maintain low background pressure, atoms of a vapour cell are transferred into a cold atomic beam by laser cooling techniques, and accumulated by a magneto-optic trap (MOT) in a separate part of the vacuum system. The laser cooled atoms are then transferred into dipole traps made of focused far-off-resonant laser fields in single- or crossed-beam geometry, which are superimposed with the center of the MOT. Gaussian as well as hollow Laguerre-Gaussian (LG$ ( 01)$) beam profiles are used with red-detuned or blue-detuned light, respectively. Microfabricated dielectric phase objects allow efficient and robust mode conversion of Gaussian into Laguerre-Gaussian laser beams. Trap geometries can easily be changed due to the highly flexible experimental setup. The dipole trap laser beams are focused to below 10 microns at a power of several hundred milliwatts. Typical trap parameters, at a detuning of several ten nanometers from the atomic resonance, are trag depths of few millikelvin, trap frequencies near 30-kHz, trap light scattering rates of few hundred photons per atom and second, and lifetimes of several seconds. The number of dipole-trapped atoms ranges from more than ten thousand to below ten. The dipole-trapped atoms are detected either by a photon counting system with very efficient straylight discrimination, or by recapture into the MOT, which is imaged onto a sensitive photodiode and a CCD-camera. Due to the strong AC-Stark shift imposed by the high intensity trapping light, energy-selective resonant excitation and detection of the atoms is possible. The measured energy distribution is consistent with a harmonic potential shape and allows the determination of temperatures and heating rates. In first measurements, the thermal energy is found to be about 10 % of the

(Cretaceous-Palaeogene transition) of central India: implications for ...

Indian Academy of Sciences (India)

2009-11-02

Nov 2, 2009 ... Higher up in the stratigraphic sequence, similar forms continued with simultaneous appearance of new taxa including Scabrastephanocolpites spp. At still higher stratigraphic levels, abundance of fungi especially the mycorrhizal fungi, concurrent with sharp decline in pollen/spore recovery was observed.

Parameter Screening in Microfluidics Based Hydrodynamic Single-Cell Trapping

Directory of Open Access Journals (Sweden)

B. Deng

2014-01-01

Full Text Available Microfluidic cell-based arraying technology is widely used in the field of single-cell analysis. However, among developed devices, there is a compromise between cellular loading efficiencies and trapped cell densities, which deserves further analysis and optimization. To address this issue, the cell trapping efficiency of a microfluidic device with two parallel micro channels interconnected with cellular trapping sites was studied in this paper. By regulating channel inlet and outlet status, the microfluidic trapping structure can mimic key functioning units of previously reported devices. Numerical simulations were used to model this cellular trapping structure, quantifying the effects of channel on/off status and trapping structure geometries on the cellular trapping efficiency. Furthermore, the microfluidic device was fabricated based on conventional microfabrication and the cellular trapping efficiency was quantified in experiments. Experimental results showed that, besides geometry parameters, cellular travelling velocities and sizes also affected the single-cell trapping efficiency. By fine tuning parameters, more than 95% of trapping sites were taken by individual cells. This study may lay foundation in further studies of single-cell positioning in microfluidics and push forward the study of single-cell analysis.

Trapping guidelines for area-wide fruit fly programmes

International Nuclear Information System (INIS)

2003-11-01

Different traps and lures have been developed and used over decades to survey fruit fly populations. The first attractant for male fruit flies was methyl eugenol (ME) (for Bactrocera zonata, Howlett, 1912) followed by kerosene for Mediterranean fruit fly, Ceratitis capitata, (medfly), Severin and Severin, 1913. In 1956, Angelica seed oil was used to trap medfly (Steiner et al, 1957). Beroza et al. (1961) discovered trimedlure (TML) to be effective for the same purpose. Beroza and Green, 1963, demonstrated cuelure to be an effective attractant for Bactrocera cucurbitae. Food baits based on protein solutions, fermenting sugar solutions, fruit juices, and vinegar have been used since 1918 for the capture of females of several species. The McPhail trap was the first device to be used with protein baits (McPhail, 1929). Steiner traps were developed in 1957 (Steiner et al., 1957) and Jackson traps in 1971 for TML (Harris et al., 1971). These traps are currently used in various countries for fruit fly surveys in support of control activities and eradication campaigns. The combination of a McPhail trap with a protein attractant, Jackson trap with TML, and the Steiner trap with ME or cuelure (CUE), has remained unchanged for several decades. Global trends in increasing food quality, revenue sources, and fruit and vegetable trade, has resulted in an increased worldwide movement of fruit fly species and requires refinement of survey systems. After years of validating trapping technology through coordinated research programmes (CRP's) and extensive technical assistance to member countries, the Joint Division FAO/IAEA proposes the use of proven technologies in improving trap sensitivity in area-wide fruit fly control programmes (IAEA 1996 and IAEA 1998). These proven technologies include the use of synthetic food lures such as female attractants that can be used for several species of Anastrepha, Bactrocera and Ceratitis. Other citations of information on these developments are

Trapping guidelines for area-wide fruit fly programmes

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-11-01

Different traps and lures have been developed and used over decades to survey fruit fly populations. The first attractant for male fruit flies was methyl eugenol (ME) (for Bactrocera zonata, Howlett, 1912) followed by kerosene for Mediterranean fruit fly, Ceratitis capitata, (medfly), Severin and Severin, 1913. In 1956, Angelica seed oil was used to trap medfly (Steiner et al, 1957). Beroza et al. (1961) discovered trimedlure (TML) to be effective for the same purpose. Beroza and Green, 1963, demonstrated cuelure to be an effective attractant for Bactrocera cucurbitae. Food baits based on protein solutions, fermenting sugar solutions, fruit juices, and vinegar have been used since 1918 for the capture of females of several species. The McPhail trap was the first device to be used with protein baits (McPhail, 1929). Steiner traps were developed in 1957 (Steiner et al., 1957) and Jackson traps in 1971 for TML (Harris et al., 1971). These traps are currently used in various countries for fruit fly surveys in support of control activities and eradication campaigns. The combination of a McPhail trap with a protein attractant, Jackson trap with TML, and the Steiner trap with ME or cuelure (CUE), has remained unchanged for several decades. Global trends in increasing food quality, revenue sources, and fruit and vegetable trade, has resulted in an increased worldwide movement of fruit fly species and requires refinement of survey systems. After years of validating trapping technology through coordinated research programmes (CRP's) and extensive technical assistance to member countries, the Joint Division FAO/IAEA proposes the use of proven technologies in improving trap sensitivity in area-wide fruit fly control programmes (IAEA 1996 and IAEA 1998). These proven technologies include the use of synthetic food lures such as female attractants that can be used for several species of Anastrepha, Bactrocera and Ceratitis. Other citations of information on these developments are

On-chip particle trapping and manipulation

Science.gov (United States)

Leake, Kaelyn Danielle

The ability to control and manipulate the world around us is human nature. Humans and our ancestors have used tools for millions of years. Only in recent years have we been able to control objects at such small levels. In order to understand the world around us it is frequently necessary to interact with the biological world. Optical trapping and manipulation offer a non-invasive way to move, sort and interact with particles and cells to see how they react to the world around them. Optical tweezers are ideal in their abilities but they require large, non-portable, and expensive setups limiting how and where we can use them. A cheap portable platform is required in order to have optical manipulation reach its full potential. On-chip technology offers a great solution to this challenge. We focused on the Liquid-Core Anti-Resonant Reflecting Optical Waveguide (liquid-core ARROW) for our work. The ARROW is an ideal platform, which has anti-resonant layers which allow light to be guided in liquids, allowing for particles to easily be manipulated. It is manufactured using standard silicon manufacturing techniques making it easy to produce. The planner design makes it easy to integrate with other technologies. Initially I worked to improve the ARROW chip by reducing the intersection losses and by reducing the fluorescence and background on the ARROW chip. The ARROW chip has already been used to trap and push particles along its channel but here I introduce several new methods of particle trapping and manipulation on the ARROW chip. Traditional two beam traps use two counter propagating beams. A trapping scheme that uses two orthogonal beams which counter to first instinct allow for trapping at their intersection is introduced. This scheme is thoroughly predicted and analyzed using realistic conditions. Simulations of this method were done using a program which looks at both the fluidics and optical sources to model complex situations. These simulations were also used to

Quantized motion of trapped ions

International Nuclear Information System (INIS)

Steinbach, J.

1999-01-01

This thesis is concerned with a theoretical and numerical study of the preparation and coherent manipulation of quantum states in the external and internal degrees of freedom of trapped ions. In its first part, this thesis proposes and investigates schemes for generating several nonclassical states for the quantized vibrational motion of a trapped ion. Based on dark state preparation specific laser excitation configurations are presented which, given appropriately chosen initial states, realize the desired motional states in the steady-state, indicated by the cessation of the fluorescence emitted by the ion. The focus is on the SU(1,1) intelligent states in both their single- and two-mode realization, corresponding to one- and two-dimensional motion of the ion. The presented schemes are also studied numerically using a Monte-Carlo state-vector method. The second part of the thesis describes how two vibrational degrees of freedom of a single trapped ion can be coupled through the action of suitably chosen laser excitation. Concentrating on a two-dimensional ion trap with dissimilar vibrational frequencies a variety of quantized two-mode couplings are derived. The focus is on a linear coupling that takes excitations from one mode to another. It is demonstrated how this can result in a state rotation, in which it is possible to coherently transfer the motional state of the ion between orthogonal directions without prior knowledge of that motional state. The third part of this thesis presents a new efficient method for generating maximally entangled internal states of a collection of trapped ions. The method is deterministic and independent of the number of ions in the trap. As the essential element of the scheme a mechanism for the realization of a controlled NOT operation that can operate on multiple ions is proposed. The potential application of the scheme for high-precision frequency standards is explored. (author)

A quasi-electrostatic trap for neutral atoms

International Nuclear Information System (INIS)

Engler, H.

2000-01-01

This thesis reports on the realization of a ''quasi-electrostatic trap'' (QUEST) for neutral atoms. Cesium ( 133 Cs) and Lithium ( 7 Li) atoms are stored, which represents for the first time a mixture of different species in an optical dipole trap. The trap is formed by the focused Gaussian beam of a 30 W cw CO 2 -laser. For a beam waist of 108 μm the resulting trap depth is κ B x 118 μK for Cesium and κ B x 48 μK for Lithium. We transfer up to 2 x 10 6 Cesium and 10 5 Lithium atoms from a magneto-optical trap into the QUEST. When simultaneously transferred, the atom number currently is reduced by roughly a factor of 10. Since photon scattering from the trapping light can be neglected, the QUEST represents an almost perfect conservative trapping potential. Atoms in the QUEST populate the electronic ground state sublevels. Arbitrary sublevels can be addressed via optical pumping. Due to the very low background gas pressure of 2 x 10 -11 mbar storage times of several minutes are realized. Evaporative cooling of Cesium is observed. In addition, laser cooling is applied to the trapped Cesium sample, which reduces the temperature from 25 μK to a value below 7 μK. If prepared in the upper hyper-fine ground state sublevel, spin changing collisions are observed not only within one single species, but also between the two different species. The corresponding relaxation rates are quantitatively analyzed. (orig.)

Time and financial costs of programs for live trapping feral cats.

Science.gov (United States)

Nutter, Felicia B; Stoskopf, Michael K; Levine, Jay F

2004-11-01

To determine the time and financial costs of programs for live trapping feral cats and determine whether allowing cats to become acclimated to the traps improved trapping effectiveness. Prospective cohort study. 107 feral cats in 9 colonies. 15 traps were set at each colony for 5 consecutive nights, and 5 traps were then set per night until trapping was complete. In 4 colonies, traps were immediately baited and set; in the remaining 5 colonies, traps were left open and cats were fed in the traps for 3 days prior to the initiation of trapping. Costs for bait and labor were calculated, and trapping effort and efficiency were assessed. Mean +/- SD overall trapping effort (ie, number of trap-nights until at least 90% of the cats in the colony had been captured or until no more than 1 cat remained untrapped) was 8.9 +/- 3.9 trap-nights per cat captured. Mean overall trapping efficiency (ie, percentage of cats captured per colony) was 98.0 +/- 4.0%. There were no significant differences in trapping effort or efficiency between colonies that were provided an acclimation period and colonies that were not. Overall trapping costs were significantly higher for colonies provided an acclimation period. Results suggest that these live-trapping protocols were effective. Feeding cats their regular diets in the traps for 3 days prior to the initiation of trapping did not have a significant effect on trapping effort or efficiency in the present study but was associated with significant increases in trapping costs.

Evaluation of Sediment Trap Efficiency in an Estuarine Environment

National Research Council Canada - National Science Library

Stoddard, Daniel

2001-01-01

.... A second trap of same dimensions was also incorporated 420 m upstream. Trap efficiency was calculated as a sediment removal ratio, or the percentage by which influent sediment load to the trap is reduced in the effluent load from the trap...

Geostatistical and stratigraphic analysis of deltaic reservoirs from the Reconcavo Basin, Brazil; Analise estratigrafica e geoestatistica de reservatorios deltaicos da Bacia do Reconcavo (BA)

Energy Technology Data Exchange (ETDEWEB)

Soares, Carlos Moreira

1997-07-01

This study presents the characterization of the external geometry of deltaic oil reservoirs, including the description of their areal distribution using geo statistic tools, such as variography and kriging. A high-resolution stratigraphic study was developed over a 25 km{sup 2} area, by using data from 276 closely-spaced wells of an oil-producer field from the Reconcavo Basin, northeastern Brazil. The studied succession records the progressive lacustrine transgression of a deltaic environment. Core data and stratigraphic cross sections suggest that the oil reservoirs are mostly amalgamated, delta-front lobes, and subordinately, crevasse deposits. Some important geometrical elements were recognized by the detailed variographic analysis developed for each stratigraphic unit (zone). The average width for the groups of deltaic lobes of one zone was measured from the variographic feature informally named as hole effect. This procedure was not possible for the other zones due to the intense lateral amalgamation of sandstones, indicated by many variographic nested structures. Net sand krigged maps for the main zones suggest a NNW-SSE orientation for the deltaic lobes, as also their common amalgamation and compensation arrangements. High-resolution stratigraphic analyses should include a more regional characterization of the depositional system that comprises the studied succession. On the other hand, geostatistical studies should be developed only after the recognition of the depositional processes acting in the study area and the geological meaning of the variable to be treated, including its spatial variability scales as a function of sand body thickness, orientation and amalgamation. (author)

Quantum computing with trapped ions

Energy Technology Data Exchange (ETDEWEB)

Hughes, R.J.

1998-01-01

The significance of quantum computation for cryptography is discussed. Following a brief survey of the requirements for quantum computational hardware, an overview of the ion trap quantum computation project at Los Alamos is presented. The physical limitations to quantum computation with trapped ions are analyzed and an assessment of the computational potential of the technology is made.

An Open Standard for Camera Trap Data

Directory of Open Access Journals (Sweden)

Tavis Forrester

2016-12-01

Full Text Available Camera traps that capture photos of animals are a valuable tool for monitoring biodiversity. The use of camera traps is rapidly increasing and there is an urgent need for standardization to facilitate data management, reporting and data sharing. Here we offer the Camera Trap Metadata Standard as an open data standard for storing and sharing camera trap data, developed by experts from a variety of organizations. The standard captures information necessary to share data between projects and offers a foundation for collecting the more detailed data needed for advanced analysis. The data standard captures information about study design, the type of camera used, and the location and species names for all detections in a standardized way. This information is critical for accurately assessing results from individual camera trapping projects and for combining data from multiple studies for meta-analysis. This data standard is an important step in aligning camera trapping surveys with best practices in data-intensive science. Ecology is moving rapidly into the realm of big data, and central data repositories are becoming a critical tool and are emerging for camera trap data. This data standard will help researchers standardize data terms, align past data to new repositories, and provide a framework for utilizing data across repositories and research projects to advance animal ecology and conservation.

Residual CO2 trapping in Indiana limestone.

Science.gov (United States)

El-Maghraby, Rehab M; Blunt, Martin J

2013-01-02

We performed core flooding experiments on Indiana limestone using the porous plate method to measure the amount of trapped CO(2) at a temperature of 50 °C and two pressures: 4.2 and 9 MPa. Brine was mixed with CO(2) for equilibration, then the mixture was circulated through a sacrificial core. Porosity and permeability tests conducted before and after 884 h of continuous core flooding confirmed negligible dissolution. A trapping curve for supercritical (sc)CO(2) in Indiana showing the relationship between the initial and residual CO(2) saturations was measured and compared with that of gaseous CO(2). The results were also compared with scCO(2) trapping in Berea sandstone at the same conditions. A scCO(2) residual trapping end point of 23.7% was observed, indicating slightly less trapping of scCO(2) in Indiana carbonates than in Berea sandstone. There is less trapping for gaseous CO(2) (end point of 18.8%). The system appears to be more water-wet under scCO(2) conditions, which is different from the trend observed in Berea; we hypothesize that this is due to the greater concentration of Ca(2+) in brine at higher pressure. Our work indicates that capillary trapping could contribute to the immobilization of CO(2) in carbonate aquifers.

HPLC-ESR techniques for detection of complex trapped radicals

International Nuclear Information System (INIS)

Tu Tiecheng; Dong Jirong; Lin Nianyun; Xie Leidong; Liu Rengzhong

1992-01-01

High performance liquid chromatography (HPLC) and ESR combined examination of radical species is an advanced techniques for separation and identification of complex radical species. At SRCL, Waters 990 HPLC has been used to separate the complex trapped radicals and Varian E-112 ESR spectrometer to record the spectra of single trapped radicals after HPLC separation. The advantages of the combined techniques are described as bellow: HPLC is used to separate the long-lived complex trapped radicals derived from reaction of short-lived radicals with spin trap. ESR spectra from single trapped radicals, obtained following HPLC separation of complex trapped radicals, are recorded one by one and well resolved. The structures of short-lived radicals can be inferred from the ESR spectra of the long-lived trapped radicals

Investigation of two-frequency Paul traps for antihydrogen production

Energy Technology Data Exchange (ETDEWEB)

Leefer, Nathan; Krimmel, Kai, E-mail: kkrimmel@students.uni-mainz.de [Helmholtz-Institut Mainz (Germany); Bertsche, William [University of Manchester (United Kingdom); Budker, Dmitry [Helmholtz-Institut Mainz (Germany); Fajans, Joel [University of California at Berkeley, Department of Physics (United States); Folman, Ron [Ben-Gurion University of the Negev, Department of Physics (Israel); Häffner, Hartmut [University of California at Berkeley, Department of Physics (United States); Schmidt-Kaler, Ferdinand [Helmholtz-Institut Mainz (Germany)

2017-11-15

Radio-frequency (rf) Paul traps operated with multifrequency rf trapping potentials provide the ability to independently confine charged particle species with widely different charge-to-mass ratios. In particular, these traps may find use in the field of antihydrogen recombination, allowing antiproton and positron clouds to be trapped and confined in the same volume without the use of large superconducting magnets. We explore the stability regions of two-frequency Paul traps and perform numerical simulations of small samples of multispecies charged-particle mixtures of up to twelve particles that indicate the promise of these traps for antihydrogen recombination.

Spectroscopy with trapped highly charged ions

International Nuclear Information System (INIS)

Beiersdorfer, Peter

2009-01-01

We give an overview of atomic spectroscopy performed on electron beam ion traps at various locations throughout the world. Spectroscopy at these facilities contributes to various areas of science and engineering, including but not limited to basic atomic physics, astrophysics, extreme ultraviolet lithography, and the development of density and temperature diagnostics of fusion plasmas. These contributions are accomplished by generating, for example, spectral surveys, making precise radiative lifetime measurements, accounting for radiative power emitted in a given wavelength band, illucidating isotopic effects, and testing collisional-radiative models. While spectroscopy with electron beam ion traps had originally focused on the x-ray emission from highly charged ions interacting with the electron beam, the operating modes of such devices have expanded to study radiation in almost all wavelength bands from the visible to the hard x-ray region; and at several facilities the ions can be studied even in the absence of an electron beam. Photon emission after charge exchange or laser excitation has been observed; and the work is no longer restricted to highly charged ions. Much of the experimental capabilities are unique to electron beam ion traps, and the work performed with these devices cannot be undertaken elsewhere. However, in other areas the work on electron beam ion traps rivals the spectroscopy performed with conventional ion traps or heavy-ion storage rings. The examples we present highlight many of the capabilities of the existing electron beam ion traps and their contributions to physics.

Scaling ion traps for quantum computing

CSIR Research Space (South Africa)

Uys, H

2010-09-01

Full Text Available The design, fabrication and preliminary testing of a chipscale, multi-zone, surface electrode ion trap is reported. The modular design and fabrication techniques used are anticipated to advance scalability of ion trap quantum computing architectures...

Electron scattering by trapped fermionic atoms

International Nuclear Information System (INIS)

Wang Haijun; Jhe, Wonho

2002-01-01

Considering the Fermi gases of alkali-metal atoms that are trapped in a harmonic potential, we study theoretically the elastic and inelastic scattering of the electrons by the trapped Fermi atoms and present the corresponding differential cross sections. We also obtain the stopping power for the cases that the electronic state as well as the center-of-mass state are excited both separately and simultaneously. It is shown that the elastic scattering process is no longer coherent in contrast to the electron scattering by the atomic Bose-Einstein condensate (BEC). For the inelastic scattering process, on the other hand, the differential cross section is found to be proportional to the 2/3 power of the number of the trapped atoms. In particular, the trapped fermionic atoms display the effect of ''Fermi surface,'' that is, only the energy levels near the Fermi energy have dominant contributions to the scattering process. Moreover, it is found that the stopping power scales as the 7/6 power of the atomic number. These results are fundamentally different from those of the electron scattering by the atomic BEC, mainly due to the different statistics obeyed by the trapped atomic systems

Interface and oxide traps in high-κ hafnium oxide films

International Nuclear Information System (INIS)

Wong, H.; Zhan, N.; Ng, K.L.; Poon, M.C.; Kok, C.W.

2004-01-01

The origins of the interface trap generation and the effects of thermal annealing on the interface and bulk trap distributions are studied in detail. We found that oxidation of the HfO 2 /Si interface, removal of deep trap centers, and crystallization of the as-deposited film will take place during the post-deposition annealing (PDA). These processes will result in the removal of interface traps and deep oxide traps and introduce a large amount of shallow oxide traps at the grain boundaries of the polycrystalline film. Thus, trade-off has to be made in considering the interface trap density and oxide trap density when conducting PDA. In addition, the high interface trap and oxide trap densities of the HfO 2 films suggest that we may have to use the SiO 2 /HfO 2 stack or hafnium silicate structure for better device performance

Sediment Trapping in Estuaries

Science.gov (United States)

Burchard, Hans; Schuttelaars, Henk M.; Ralston, David K.

2018-01-01

Estuarine turbidity maxima (ETMs) are generated by a large suite of hydrodynamic and sediment dynamic processes, leading to longitudinal convergence of cross-sectionally integrated and tidally averaged transport of cohesive and noncohesive suspended particulate matter (SPM). The relative importance of these processes for SPM trapping varies substantially among estuaries depending on topography, fluvial and tidal forcing, and SPM composition. The high-frequency dynamics of ETMs are constrained by interactions with the low-frequency dynamics of the bottom pool of easily erodible sediments. Here, we use a transport decomposition to present processes that lead to convergent SPM transport, and review trapping mechanisms that lead to ETMs at the landward limit of the salt intrusion, in the freshwater zone, at topographic transitions, and by lateral processes within the cross section. We use model simulations of example estuaries to demonstrate the complex concurrence of ETM formation mechanisms. We also discuss how changes in SPM trapping mechanisms, often caused by direct human interference, can lead to the generation of hyperturbid estuaries.

Trapping and Evolution Dynamics of Ultracold Two-Component Plasmas

International Nuclear Information System (INIS)

Choi, J.-H.; Knuffman, B.; Zhang, X. H.; Povilus, A. P.; Raithel, G.

2008-01-01

We demonstrate the trapping of a strongly magnetized, quasineutral ultracold plasma in a nested Penning trap with a background field of 2.9 T. Electrons remain trapped in this system for several milliseconds. Early in the evolution, the dynamics are driven by a breathing-mode oscillation in the ionic charge distribution, which modulates the electron trap depth. Over longer times scales, the electronic component undergoes cooling. Trap loss resulting from ExB drift is characterized

Evaluation of double-decker traps for emerald ash borer (Coleoptera: Buprestidae).

Science.gov (United States)

Poland, Therese M; McCullough, Deborah G; Anulewicz, Andrea C

2011-04-01

Improved detection tools are needed for the emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), an invasive forest insect from Asia that has killed millions of ash (Fraxinus spp.) trees in North America since its discovery in Michigan in 2002. We evaluated attraction of adult A. planipennis to artificial traps incorporating visual (e.g., height, color, silhouette) and olfactory cues (e.g., host volatiles) at field sites in Michigan. We developed a double-decker trap consisting of a 3-m-tall polyvinyl pipe with two purple prisms attached near the top. In 2006, we compared A. planipennis attraction to double-decker traps baited with various combinations of manuka oil (containing sesquiterpenes present in ash bark), a blend of four ash leaf volatiles (leaf blend), and a rough texture to simulate bark. Significantly more A. planipennis were captured per trap when traps without the rough texture were baited with the leaf blend and manuka oil lures than on traps with texture and manuka oil but no leaf blend. In 2007, we also tested single prism traps set 1.5 m above ground and tower traps, similar to double-decker traps but 6 m tall. Double-decker traps baited with the leaf blend and manuka oil, with or without the addition of ash leaf and bark extracts, captured significantly more A. planipennis than similarly baited single prism traps, tower traps, or unbaited double-decker traps. A baited double-decker trap captured A. planipennis at a field site that was not previously known to be infested, representing the first detection event using artificial traps and lures. In 2008, we compared purple or green double-decker traps, single prisms suspended 3-5 m above ground in the ash canopy (canopy traps), and large flat purple traps (billboard traps). Significantly more A. planipennis were captured in purple versus green traps, baited traps versus unbaited traps, and double-decker versus canopy traps, whereas billboard traps were intermediate. At sites

Modified semiclassical approximation for trapped Bose gases

International Nuclear Information System (INIS)

Yukalov, V.I.

2005-01-01

A generalization of the semiclassical approximation is suggested allowing for an essential extension of its region of applicability. In particular, it becomes possible to describe Bose-Einstein condensation of a trapped gas in low-dimensional traps and in traps of low confining dimensions, for which the standard semiclassical approximation is not applicable. The result of the modified approach is shown to coincide with purely quantum-mechanical calculations for harmonic traps, including the one-dimensional harmonic trap. The advantage of the semiclassical approximation is in its simplicity and generality. Power-law potentials of arbitrary powers are considered. The effective thermodynamic limit is defined for any confining dimension. The behavior of the specific heat, isothermal compressibility, and density fluctuations is analyzed, with an emphasis on low confining dimensions, where the usual semiclassical method fails. The peculiarities of the thermodynamic characteristics in the effective thermodynamic limit are discussed

TRAP230/ARC240 and TRAP240/ARC250 Mediator subunits are functionally conserved through evolution

DEFF Research Database (Denmark)

Samuelsen, Camilla O; Baraznenok, Vera; Khorosjutina, Olga

2003-01-01

In Saccharomyces cerevisiae Mediator, a subgroup of proteins (Srb8, Srb9, Srb10, and Srb11) form a module, which is involved in negative regulation of transcription. Homologues of Srb10 and Srb11 are found in some mammalian Mediator preparations, whereas no clear homologues have been reported...... for Srb8 and Srb9. Here, we identify a TRAP240/ARC250 homologue in Schizosaccharomyces pombe and demonstrate that this protein, spTrap240, is stably associated with a larger form of Mediator, which also contains conserved homologues of Srb8, Srb10, and Srb11. We find that spTrap240 and Sch. pombe Srb8 (sp......Srb8) regulate the same distinct subset of genes and have indistinguishable phenotypic characteristics. Importantly, Mediator containing the spSrb8/spTrap240/spSrb10/spSrb11 subunits is isolated only in free form, devoid of RNA polymerase II. In contrast, Mediator lacking this module associates...

Novel Ion Trap Design for Strong Ion-Cavity Coupling

Directory of Open Access Journals (Sweden)

Alejandro Márquez Seco

2016-04-01

Full Text Available We present a novel ion trap design which facilitates the integration of an optical fiber cavity into the trap structure. The optical fibers are confined inside hollow electrodes in such a way that tight shielding and free movement of the fibers are simultaneously achievable. The latter enables in situ optimization of the overlap between the trapped ions and the cavity field. Through numerical simulations, we systematically analyze the effects of the electrode geometry on the trapping characteristics such as trap depths, secular frequencies and the optical access angle. Additionally, we simulate the effects of the presence of the fibers and confirm the robustness of the trapping potential. Based on these simulations and other technical considerations, we devise a practical trap configuration that isviable to achieve strong coupling of a single ion.

The ALPHA antihydrogen trapping apparatus

Energy Technology Data Exchange (ETDEWEB)

Amole, C. [Department of Physics and Astronomy, York University, Toronto ON Canada, M3J 1P3 (Canada); Andresen, G.B. [Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark); Ashkezari, M.D. [Department of Physics, Simon Fraser University, Burnaby, BC Canada, V5A 1S6 (Canada); Baquero-Ruiz, M. [Department of Physics, University of California at Berkeley, Berkeley, CA 94720-7300 (United States); Bertsche, W. [Department of Physics, College of Science, Swansea University, Swansea SA2 8PP (United Kingdom); School of Physics and Astronomy, University of Manchester, Manchester M13 9PL (United Kingdom); The Cockcroft Institute, Warrington WA4 4AD (United Kingdom); Bowe, P.D. [Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark); Butler, E. [Physics Department, CERN, CH-1211 Geneva 23 (Switzerland); Capra, A. [Department of Physics and Astronomy, York University, Toronto ON Canada, M3J 1P3 (Canada); Carpenter, P.T. [Department of Physics, Auburn University, Auburn, AL 36849-5311 (United States); Cesar, C.L. [Instituto de Física, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-972 (Brazil); Chapman, S. [Department of Physics, University of California at Berkeley, Berkeley, CA 94720-7300 (United States); Charlton, M.; Deller, A.; Eriksson, S. [Department of Physics, College of Science, Swansea University, Swansea SA2 8PP (United Kingdom); Escallier, J. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Fajans, J. [Department of Physics, University of California at Berkeley, Berkeley, CA 94720-7300 (United States); Friesen, T. [Department of Physics and Astronomy, University of Calgary, Calgary AB, Canada, T2N 1N4 (Canada); Fujiwara, M.C.; Gill, D.R. [TRIUMF, 4004 Wesbrook Mall, Vancouver BC, Canada V6T 2A3 (Canada); Gutierrez, A. [Department of Physics and Astronomy, University of British Columbia, Vancouver BC, Canada V6T 1Z4 (Canada); and others

2014-01-21

The ALPHA collaboration, based at CERN, has recently succeeded in confining cold antihydrogen atoms in a magnetic minimum neutral atom trap and has performed the first study of a resonant transition of the anti-atoms. The ALPHA apparatus will be described herein, with emphasis on the structural aspects, diagnostic methods and techniques that have enabled antihydrogen trapping and experimentation to be achieved.

Trapped Ion Qubits

Energy Technology Data Exchange (ETDEWEB)

Maunz, Peter Lukas Wilhelm

2017-04-01

Qubits can be encoded in clock states of trapped ions. These states are well isolated from the environment resulting in long coherence times [1] while enabling efficient high-fidelity qubit interactions mediated by the Coulomb coupled motion of the ions in the trap. Quantum states can be prepared with high fidelity and measured efficiently using fluorescence detection. State preparation and detection with 99.93% fidelity have been realized in multiple systems [1,2]. Single qubit gates have been demonstrated below rigorous fault-tolerance thresholds [1,3]. Two qubit gates have been realized with more than 99.9% fidelity [4,5]. Quantum algorithms have been demonstrated on systems of 5 to 15 qubits [6–8].

Camera Traps Can Be Heard and Seen by Animals

Science.gov (United States)

Meek, Paul D.; Ballard, Guy-Anthony; Fleming, Peter J. S.; Schaefer, Michael; Williams, Warwick; Falzon, Greg

2014-01-01

Camera traps are electrical instruments that emit sounds and light. In recent decades they have become a tool of choice in wildlife research and monitoring. The variability between camera trap models and the methods used are considerable, and little is known about how animals respond to camera trap emissions. It has been reported that some animals show a response to camera traps, and in research this is often undesirable so it is important to understand why the animals are disturbed. We conducted laboratory based investigations to test the audio and infrared optical outputs of 12 camera trap models. Camera traps were measured for audio outputs in an anechoic chamber; we also measured ultrasonic (n = 5) and infrared illumination outputs (n = 7) of a subset of the camera trap models. We then compared the perceptive hearing range (n = 21) and assessed the vision ranges (n = 3) of mammals species (where data existed) to determine if animals can see and hear camera traps. We report that camera traps produce sounds that are well within the perceptive range of most mammals’ hearing and produce illumination that can be seen by many species. PMID:25354356

Camera traps can be heard and seen by animals.

Directory of Open Access Journals (Sweden)

Paul D Meek

Full Text Available Camera traps are electrical instruments that emit sounds and light. In recent decades they have become a tool of choice in wildlife research and monitoring. The variability between camera trap models and the methods used are considerable, and little is known about how animals respond to camera trap emissions. It has been reported that some animals show a response to camera traps, and in research this is often undesirable so it is important to understand why the animals are disturbed. We conducted laboratory based investigations to test the audio and infrared optical outputs of 12 camera trap models. Camera traps were measured for audio outputs in an anechoic chamber; we also measured ultrasonic (n = 5 and infrared illumination outputs (n = 7 of a subset of the camera trap models. We then compared the perceptive hearing range (n = 21 and assessed the vision ranges (n = 3 of mammals species (where data existed to determine if animals can see and hear camera traps. We report that camera traps produce sounds that are well within the perceptive range of most mammals' hearing and produce illumination that can be seen by many species.

Interfacial dynamic surface traps of lead sulfide (PbS) nanocrystals: test-platform for interfacial charge carrier traps at the organic/inorganic functional interface

Science.gov (United States)

Kim, Youngjun; Ko, Hyungduk; Park, Byoungnam

2018-04-01

Nanocrystal (NC) size and ligand dependent dynamic trap formation of lead sulfide (PbS) NCs in contact with an organic semiconductor were investigated using a pentacene/PbS field effect transistor (FET). We used a bilayer pentacene/PbS FET to extract information of the surface traps of PbS NCs at the pentacene/PbS interface through the field effect-induced charge carrier density measurement in the threshold and subthreshold regions. PbS size and ligand dependent trap properties were elucidated by the time domain and threshold voltage measurements in which threshold voltage shift occurs by carrier charging and discharging in the trap states of PbS NCs. The observed threshold voltage shift is interpreted in context of electron trapping through dynamic trap formation associated with PbS NCs. To the best of our knowledge, this is the first demonstration of the presence of interfacial dynamic trap density of PbS NC in contact with an organic semiconductor (pentacene). We found that the dynamic trap density of the PbS NC is size dependent and the carrier residence time in the specific trap sites is more sensitive to NC size variation than to NC ligand exchange. The probing method presented in the study offers a means to investigate the interfacial surface traps at the organic-inorganic hetero-junction, otherwise understanding of the buried surface traps at the functional interface would be elusive.

Random-walk simulation of diffusion-controlled processes among static traps

International Nuclear Information System (INIS)

Lee, S.B.; Kim, I.C.; Miller, C.A.; Torquato, S.; Department of Mechanical and Aerospace Engineering and Department of Chemical Engineering, North Carolina State University, Raleigh, North Carolina 27695-7910)

1989-01-01

We present computer-simulation results for the trapping rate (rate constant) k associated with diffusion-controlled reactions among identical, static spherical traps distributed with an arbitrary degree of impenetrability using a Pearson random-walk algorithm. We specifically consider the penetrable-concentric-shell model in which each trap of diameter σ is composed of a mutually impenetrable core of diameter λσ, encompassed by a perfectly penetrable shell of thickness (1-λ)σ/2: λ=0 corresponding to randomly centered or ''fully penetrable'' traps and λ=1 corresponding to totally impenetrable traps. Trapping rates are calculated accurately from the random-walk algorithm at the extreme limits of λ (λ=0 and 1) and at an intermediate value (λ=0.8), for a wide range of trap densities. Our simulation procedure has a relatively fast execution time. It is found that k increases with increasing impenetrability at fixed trap concentration. These ''exact'' data are compared with previous theories for the trapping rate. Although a good approximate theory exists for the fully-penetrable-trap case, there are no currently available theories that can provide good estimates of the trapping rate for a moderate to high density of traps with nonzero hard cores (λ>0)

Recognition of Milankovitch cycles in the stratigraphic record:application of the CWT and the FFT to well-log data

Institute of Scientific and Technical Information of China (English)

YU Ji-feng; SUI Feng-gui; LI Zeng-xue; LIU Hua; WANG Yu-lin

2008-01-01

The authors applied a the combination of Continuous Wavelet Transform (CWT) and Fast Fourier Transform (FFF)methods to gamma ray well-log data from the Q3, G1 and D2 wells. This high-resolution stratigraphic study was based on Milankovitch's orbital cycle theory. It was found that the CWT scale factors, 'a,' of 12, 24 and 60 match the ratios of the periodicities of precession, obliquity and eccentricity very well. Nine intervals of the Permo-carboniferous strata were recognized to have Milankovitch cycles in them. For example, section A of well Q3 has 29 precession cycles, 15 obliquity cycles and 7 short eccentricity cycles. The wavelengths are 2.7, 4.4 and 7.8 m for precession, obliquity and eccentricity, respectively. Important geological parameters such as the stratigraphic completeness and the accumulation rate were also estimated. These results provide basic information for further cyclostratigraphic correlation studies in the area. They are of great significance for the study of ancient and future climate change.

Trapping of Rydberg atoms in tight magnetic microtraps

NARCIS (Netherlands)

Boetes, A.Q.G.; Skannrup, R.V.; Naber, J.; Kokkelmans, S.J.J.M.F.; Spreeuw, R.J.C.

2018-01-01

We explore the possibility to trap Rydberg atoms in tightly confining magnetic microtraps. The trapping frequencies for Rydberg atoms are expected to be influenced strongly by magnetic-field gradients. We show that there are regimes where Rydberg atoms can be trapped. Moreover, we show that

Effects of abscisic acid and nitric oxide on trap formation and trapping of nematodes by the fungus Drechslerella stenobrocha AS6.1.

Science.gov (United States)

Xu, Ling-Ling; Lai, Yi-Ling; Wang, Lin; Liu, Xing-Zhong

2011-02-01

The in vitro effects of abscisic acid (ABA) and nitric oxide (NO) on the nematode-trapping fungus Drechslerella stenobrocha AS6.1 were examined. The average number of traps (constricting rings) per colony and the percentage of nematodes (Caenorhabditis elegans) trapped were greatly increased by addition of ABA but greatly suppressed by addition of sodium nitroprusside (SNP, an NO donor) to corn meal agar. The suppressive effect of SNP was not negated by addition of an NO synthase competitive inhibitor (l-naphthylacetic acid, L-NNA) or an NO-specific scavenger [2-(4-carboxyphenyl)-4,4, 5,5-tetramethylimidazoline-1-oxyl-3-oxide, cPTIO]. When added without SNP, however, L-NNA and cPTIO caused moderate increases in trap number and trapping. The results indicate that the trap formation and nematode-trapping ability of D. stenobrocha were enhanced by ABA but decreased by exogenous NO. Copyright © 2010 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

3D stratigraphic forward modelling of Shu'aiba Platform stratigraphy in the Bu Hasa Field, Abu Dhabi, United Arab Emirates.

Science.gov (United States)

Hu, J.; Lokier, S. W.

2012-04-01

This paper presents the results of three dimensional sequence stratigraphic forward modelling of the Aptian age Shu'aiba Formation from Abu Dhabi, United Arab Emirates (UAE). The Shu'aiba Formation lies within the uppermost part of the Lower Cretaceous Thamama Group and forms one of the most prolific hydrocarbon reservoir intervals of the Middle East with production dating back to the 1960's. The Shu'aiba Formation developed as a series of laterally-extensive shallow-water carbonate platforms in an epeiric sea that extended over the northern margin of the African-Arabian Plate. This shallow sea was bounded by the Arabian Shield to the west and the passive margin with the Neo-Tethys Ocean towards the north and east (Droste, 2010). The exposed Arabian Shield acted as a source of siliciclastic sediments to westernmost regions, however, more offshore areas were dominated by shallow-water carbonate deposition. Carbonate production was variously dominated by Lithocodium-Baccinella, orbitolinid foraminifera and rudist bivalves depending on local conditions. While there have been numerous studies of this important stratigraphic interval (for examples see van Buchem et al., 2010), there has been little attempt to simulate the sequence stratigraphic development of the formation. During the present study modelling was undertaken utilising the CARBONATE-3D stratigraphic forward modelling software (Warrlich et al., 2008; Warrlich et al., 2002)) thus allowing for the control of a diverse range of internal and external parameters on carbonate sequence development. This study focuses on platform development in the onshore Bu Hasa Field - the first giant oilfield to produce from the Shu'aiba Formation in Abu Dhabi. The carbonates of the Bu Hasa field were deposited on the southwest slope of the intra-shelf Bab Basin, siliciclastic content is minor. Initially these carbonates were algal dominated with rudist mounds becoming increasingly important over time (Alsharhan, 1987

Neogene and Quaternary geology of a stratigraphic test hole on Horn Island, Mississippi Sound

Science.gov (United States)

Gohn, Gregory S.; Brewster-Wingard, G. Lynn; Cronin, Thomas M.; Edwards, Lucy E.; Gibson, Thomas G.; Rubin, Meyer; Willard, Debra A.

1996-01-01

During April and May, 1991, the U.S. Geological Survey (USGS) drilled a 510-ft-deep, continuously cored, stratigraphic test hole on Horn Island, Mississippi Sound, as part of a field study of the Neogene and Quaternary geology of the Mississippi coastal area. The USGS drilled two new holes at the Horn Island site. The first hole was continuously cored to a depth of 510 ft; coring stopped at this depth due to mechanical problems. To facilitate geophysical logging, an unsampled second hole was drilled to a depth of 519 ft at the same location.

A Pneumatic Actuated Microfluidic Beads-Trapping Device

Energy Technology Data Exchange (ETDEWEB)

Shao, Guocheng; Cai, Ziliang; Wang, Jun; Wang, Wanjun; Lin, Yuehe

2011-08-20

The development of a polydimethylsiloxane (PDMS) microfluidic microbeads trapping device is reported in this paper. Besides fluid channels, the proposed device includes a pneumatic control chamber and a beads-trapping chamber with a filter array structure. The pneumatic flow control chamber and the beads-trapping chamber are vertically stacked and separated by a thin membrane. By adjusting the pressure in the pneumatic control chamber, the membrane can either be pushed against the filter array to set the device in trapping mode or be released to set the device in releasing mode. In this paper, a computational fluid dynamics simulation was conducted to optimize the geometry design of the filter array structure; the device fabrication was also carried out. The prototype device was tested and the preliminary experimental results showed that it can be used as a beads-trapping unit for various biochemistry and analytical chemistry applications, especially for flow injection analysis systems.

Geomagnetically trapped carbon, nitrogen, and oxygen nuclei.

Science.gov (United States)

Mogro-Campero, A.

1972-01-01

Results of measurements carried out with the University of Chicago nuclear composition telescope on the Ogo 5 satellite, establishing the presence of 13- to 33-MeV/nucleon geomagnetically trapped C and O nuclei, with some evidence for N nuclei. These trapped nuclei were found at L less than or equal to 5 and near the geomagnetic equator. The data cover the period from Mar. 3, 1968, to Dec. 31, 1969. The distribution of CNO flux as a function of L is given. No change in the intensity of the average trapped CNO flux was detected by comparing data for 1968 and 1969. The results reported set a new value for the observed high energy limit of trapping as described by the critical adiabaticity parameter. The penetration of solar flare CNO up to L = 4 was observed twice in 1968, in disagreement with Stormer theory predictions. The effects of these results on some models for the origin of the trapped radiation are discussed.

Ions kinematics in an electrostatic ion beam trap

Energy Technology Data Exchange (ETDEWEB)

Attia, D

2004-06-01

In this study, I have tried to provide a better understanding of the dynamics of ions inside an electrostatic ion beam trap. The electrostatic ion trap allows to store ions moving between two electrostatic mirrors. Although the trap has been developed already seven years ago, no direct measurement of the transversal velocity distribution of the ions has been performed. Such quantity is central for understanding the conditions under which a beam should be produced (mainly emittance) in order to be trapped by such a device. The data I have obtained during the course of this work are based on an experimental technique which relies on the direct imaging of the particles exiting the trap, as well as on numerical simulations of the ion trajectories inside the trap. I have personally been involved in the hardware development of the imaging system, the data acquisition and analysis of the data as well as il all numerical calculations presented here. These results allow us to obtain, for the first time, experimental information on the transverse phase space of the trap, and contribute to the overall understanding of the ion motion in this system. (author)

Cooling and trapping neutral atoms with radiative forces

International Nuclear Information System (INIS)

Bagnato, V.S.; Castro, J.C.; Li, M.S.; Zilio, S.C.

1988-01-01

Techniques to slow and trap neutral atoms at high densities with radiative forces are discussed in this review articles. Among several methods of laser cooling, it is emphasized Zeeman Tuning of the electronic levels and frequency-sweeping techniques. Trapping of neutral atoms and recent results obtained in light and magnetic traps are discussed. Techniques to further cool atoms inside traps are presented and the future of laser cooling of neutral atoms by means of radiation pressure is discussed. (A.C.A.S.) [pt

Open trap with ambipolar mirrors

International Nuclear Information System (INIS)

Dimov, G.I.; Zakajdakov, V.V.; Kishinevskij, M.E.

1977-01-01

Results of numerical calculations on the behaviour of a thermonuclear plasma, allowing for α-particles in a trap with longitudinal confinement of the main ions by ambipolar electric fields are presented. This trap is formed by connecting two small-volume ''mirrortrons'' to an ordinary open trap. Into the extreme mirrortrons, approximately 1-MeV ions are introduced continuously by ionization of atomic beams on the plasma, and approximately 10-keV ions are similarly introduced into the main central region of the trap. By a suitable choice of injection currents, the plasma density established in the extreme mirrortrons is higher than in the central region. As a result of the quasi-neutrality condition, a longitudinal ambipolar field forming a potential well not only for electrons but also for the central ions is formed in the plasma. When the depth of the well for the central ions is much greater than their temperature, their life-time considerably exceeds the time of confinement by the magnetic mirrors. As a result, the plasma density is constant over the entire length of the central mirrortron, including the regions near the mirrors, and an ambipolar field is formed only in the extreme mirrortrons. The distribution of central ions and ambipolar potential in the extreme mirrortrons is uniquely determined by the density distribution of fast extreme ions. It is shown in the present study that an amplification coefficient Q as high as desired can, in principle, be reached in the trap under consideration, allowing for α-particles. However, this requires high magnetic fields in the mirrors and a sufficient length of the central mirrotron. It is shown that for moderate values of Q=3-8, it is desirable not to confine the central fast α-particles. To achieve a coefficient of Q=5, it is necessary to create fields of 250 kG in the mirrors, and the length of the trap must not be greater than 100 m. (author)

Forest tent caterpillar, Malacosoma disstria (Lepidoptera: Lasiocampidae mate-finding behavior is greatest at intermediate population densities: Implications for interpretation of moth capture in pheromone-baited traps.

Directory of Open Access Journals (Sweden)

Maya L. Evenden

2015-07-01

Full Text Available The forest tent caterpillar, Malacosoma disstria Hübner (Lepidoptera: Lasiocampidae is a native forest defoliator with a broad geographic range in North America. Forest tent caterpillars experience cyclical population changes and at high densities, repeated defoliation can cause reduced tree growth and tree mortality. Pheromone-based monitoring of forest tent caterpillar moths can provide information on spatial and temporal patterns of incipient outbreaks. Pheromone-baited trap capture of male moths correlates to the number of eggs and pupae in a population but this relationship breaks down at high population densities, when moth trap capture declines. The objective of the current study is to understand the mechanisms that reduce trap capture at high population densities. We tested two different hypotheses: 1 at high population densities, male moth orientation to pheromone sources is reduced due to competition for pheromone plumes; and 2 moths from high density populations will be in poor condition and less likely to conduct mate-finding behaviors than moths from low density populations. A field study showed non-linear effects of density on male moth capture in female-baited traps. The number of males captured increased up to an intermediate density level and declined at the highest densities. Field cage studies showed that female moth density affected male moth orientation to female-baited traps, as more males were recaptured at low than high female densities. There was no effect of male density on the proportion of males that oriented to female-baited traps. Moth condition was manipulated by varying larval food quantity. Although feeding regimes affected the moth condition (size, there was no evidence of an effect of condition on mate finding or close range mating behavior. In the field, it is likely that competition for pheromone plumes at high female densities during population outbreaks reduces the efficacy of pheromone-baited monitoring

Colored Sticky Traps to Selectively Survey Thrips in Cowpea Ecosystem.

Science.gov (United States)

Tang, L D; Zhao, H Y; Fu, B L; Han, Y; Liu, K; Wu, J H

2016-02-01

The bean flower thrips, Megalurothrips usitatus (Bagrall) (Thysanoptera: Thripidae), is an important pest of legume crops in South China. Yellow, blue, or white sticky traps are currently recommended for monitoring and controlling thrips, but it is not known whether one is more efficient than the other or if selectivity could be optimized by trap color. We investigated the response of thrips and beneficial insects to different-colored sticky traps on cowpea, Vigna unguiculata. More thrips were caught on blue, light blue, white, and purple traps than on yellow, green, pink, gray, red, or black traps. There was a weak correlation on the number of thrips caught on yellow traps and survey from flowers (r = 0.139), whereas a strong correlation was found for blue traps and thrips' survey on flowers (r = 0.929). On commercially available sticky traps (Jiaduo®), two and five times more thrips were caught on blue traps than on white and yellow traps, respectively. Otherwise, capture of beneficial insects was 1.7 times higher on yellow than on blue traps. The major natural enemies were the predatory ladybird beetles (63%) and pirate bugs Orius spp. (29%), followed by a number of less representative predators and parasitoids (8%). We conclude the blue sticky trap was the best to monitor thrips on cowpea in South China.

Stratigraphic controls on saltwater intrusion in the Dominguez Gap area of coastal Los Angeles

Science.gov (United States)

Edwards, B.D.; Ehman, K.D.; Ponti, D.J.; Reichard, E.G.; Tinsley, J.C.; Rosenbauer, R.J.; Land, M.

2009-01-01

The Los Angeles Basin is a densely populated coastal area that significantly depends on groundwater. A part of this groundwater supply is at risk from saltwater intrusion-the impetus for this study. High-resolution seismic-reflection data collected from the Los Angeles-Long Beach Harbor Complex have been combined with borehole geophysical and descriptive geological data from four nearby ??400-m-deep continuously cored wells and with borehole geophysical data from adjacent water and oil wells to characterize the Pliocene to Holocene stratigraphy of the Dominguez Gap coastal aquifer system. The new data are shown as a north-south, two- dimensional, sequence-stratigraphic model that is compared to existing lithostratigraphic models of the Los Angeles Basin in an attempt to better understand pathways of saltwater intrusion into coastal aquifers. Intrusion of saltwater into the coastal aquifer system generally is attributed to over-pumping that caused the hydraulic gradient to reverse during the mid-1920s. Local water managers have used the existing lithostratigraphic model to site closely spaced injection wells of freshwater (barrier projects) attempting to hydraulically control the saltwater intrusion. Improved understanding of the stratigraphic relationships can guide modifications to barrier design that will allow more efficient operation. Allostratigraphic nomenclature is used to define a new sequence-stratigraphic model for the area because the existing lithostratigraphic correlations that have been used to define aquifer systems are shown not to be time-correlative. The youngest sequence, the Holocene Dominguez sequence, contains the Gaspur aquifer at its base. The Gaspur aquifer is intruded with saltwater and consists of essentially flat-lying gravelly sands deposited by the ancestral Los Angeles River as broad channels that occupied a paleovalley incised into the coastal plain during the last glacio-eustatic highstand. The underlying sequences are deformed into

Magnetic multipole induced zero-rotation frequency bounce-resonant loss in a Penning–Malmberg trap used for antihydrogen trapping

CERN Document Server

Andresen, G B; Bray, C; Butler, E; Cesar, C L; Chapman, S; Charlton, M; Fajans, J; Fujiwara, M C; Gill, D R; Hardy, W N; Hayano, R S; Hayden, M E; Humphries, A J; Hydomako, R; Jørgensen, L V; Kerrigan, S J; Keller, J; Kurchaninov, L; Lambo, R; Madsen, N; Nolan, P; Olchanski, K; Olin, A; Povilus, A; Pusa, P; Robicheaux, F; Sarid, E; Seif El Nasr, S; Silveira, D M; Storey, J W; Thompson, R I; van der Werf, D P; Wurtele, J S; Yamazaki, Y

2009-01-01

In many antihydrogen trapping schemes, antiprotons held in a short-well Penning–Malmberg trap are released into a longer well. This process necessarily causes the bounce-averaged rotation frequency $\\overline{\\Omega}_r$ of the antiprotons around the trap axis to pass through zero. In the presence of a transverse magnetic multipole, experiments and simulations show that many antiprotons (over 30% in some cases) can be lost to a hitherto unidentified bounce-resonant process when $\\overline{\\Omega}_r$ is close to zero.

Stratigraphical discontinuities, tropical landscape evolution and soil distribution relationships in a case study in SE-Brazil

Directory of Open Access Journals (Sweden)

M. Cooper

2002-09-01

Full Text Available On a regional summit surface in the county of Piracicaba (SP within the Peripheric Depression of São Paulo, formed of discontinued flattened tops, there is an abrupt transition between a Typic Hapludox and a Kandiudalfic Eutrudox, together with two stoneline layers. Using stratigraphical, mineralogical, and cartographic studies, this transition and the soil distribution of this surface were studied, correlating them with the different parent materials and the morphoclimatic model of landscape evolution in Southeastern Brazil. The Typic Hapludox was formed on a sandy Cenozoic deposit (Q that overlies a pellitic deposit of the Iratí formation (Pi, representing a regional erosive discordance. Westwards to the Piracicaba River, this sequence is interrupted by a diabase sill overlain by a red clayey material which gave origin to the Kandiudalfic Eutrudox. Two post-Permian depositional events were identified by the two stonelines and stratigraphical discontinuities. The first event generated the deposition of a sandy sediment in the form of levelled alveoluses on regional barriers, most of these formed by dikes and diabase sills, probably during a drier phase. The second depositional event, leading to the deposition of the red clay was probably the dissection of the previously formed pediplane during a humid climate, followed by another pedimentation process during a later, drier period.

Wettability effect on capillary trapping of supercritical CO2 at pore-scale: micromodel experiment and numerical modeling

Science.gov (United States)

Hu, R.; Wan, J.

2015-12-01

Wettability of reservoir minerals along pore surfaces plays a controlling role in capillary trapping of supercritical (sc) CO2 in geologic carbon sequestration. The mechanisms controlling scCO2 residual trapping are still not fully understood. We studied the effect of pore surface wettability on CO2 residual saturation at the pore-scale using engineered high pressure and high temperature micromodel (transparent pore networks) experiments and numerical modeling. Through chemical treatment of the micromodel pore surfaces, water-wet, intermediate-wet, and CO2-wet micromodels can be obtained. Both drainage and imbibition experiments were conducted at 8.5 MPa and 45 °C with controlled flow rate. Dynamic images of fluid-fluid displacement processes were recorded using a microscope with a CCD camera. Residual saturations were determined by analysis of late stage imbibition images of flow path structures. We performed direct numerical simulations of the full Navier-Stokes equations using a volume-of-fluid based finite-volume framework for the primary drainage and the followed imbibition for the micromodel experiments with different contact angles. The numerical simulations agreed well with our experimental observations. We found that more scCO2 can be trapped within the CO2-wet micromodel whereas lower residual scCO2 saturation occurred within the water-wet micromodels in both our experiments and the numerical simulations. These results provide direct and consistent evidence of the effect of wettability, and have important implications for scCO2 trapping in geologic carbon sequestration.

Flux trapping and shielding in irreversible superconductors

International Nuclear Information System (INIS)

Frankel, D.J.

1978-05-01

Flux trappings and shielding experiments were carried out on Pb, Nb, Pb-Bi, Nb-Sn, and Nb-Ti samples of various shapes. Movable Hall probes were used to measure fields near or inside the samples as a function of position and of applied field. The trapping of transverse multipole magnetic fields in tubular samples was accomplished by cooling the samples in an applied field and then smoothly reducing the applied field to zero. Transverse quadrupole and sextupole fields with gradients of over 2000 G/cm were trapped with typical fidelity to the original impressed field of a few percent. Transverse dipole fields of up to 17 kG were also trapped with similar fidelity. Shielding experiments were carried out by cooling the samples in zero field and then gradually applying an external field. Flux trapping and shielding abilities were found to be limited by two factors, the pinning strength of the material, and the susceptibility of a sample to flux jumping. The trapping and shielding behavior of flat disk samples in axial fields and thin-walled tubular samples in transverse fields was modeled. The models, which were based on the concept of the critical state, allowed a connection to be made between the pinning strength and critical current level, and the flux trapping and shielding abilities. Adiabatic and dynamic stability theories are discussed and applied to the materials tested. Good qualitative, but limited quantitative agreement was obtained between the predictions of the theoretical stability criteria and the observed flux jumping behavior

Gold nanoparticle trapping and delivery for therapeutic applications

Directory of Open Access Journals (Sweden)

Aziz MS

2011-12-01

Full Text Available MS Aziz1, Nathaporn Suwanpayak3,4, Muhammad Arif Jalil2, R Jomtarak4, T Saktioto2, Jalil Ali1, PP Yupapin41Institute of Advanced Photonics Science, 2Ibnu Sina Institute of Fundamental Science Studies, Nanotechnology Research Alliance, Universiti Teknologi Malaysia, Johor Bahru, Malaysia; 3King Mongkut's Institute of Technology Ladkrabang, Chump on Campus, Chumphon, 4Nanoscale Science and Engineering Research Alliance (N'SERA, Faculty of Science, King Mongkut's Institute of Technology Ladkrabang, Bangkok, ThailandAbstract: A new optical trapping design to transport gold nanoparticles using a PANDA ring resonator system is proposed. Intense optical fields in the form of dark solitons controlled by Gaussian pulses are used to trap and transport nanoscopic volumes of matter to the desired destination via an optical waveguide. Theoretically, the gradient and scattering forces are responsible for this trapping phenomenon, where in practice such systems can be fabricated and a thin-film device formed on the specific artificial medical materials, for instance, an artificial bone. The dynamic behavior of the tweezers can be tuned by controlling the optical pulse input power and parameters of the ring resonator system. Different trap sizes can be generated to trap different gold nanoparticles sizes, which is useful for gold nanoparticle therapy. In this paper, we have shown the utility of gold nanoparticle trapping and delivery for therapy, which may be useful for cosmetic therapy and related applications.Keywords: gold nanoparticle trapping, particle trapping, therapy, transport

Natural-trap ursid mortality and the Kurtén Response.

Science.gov (United States)

Wolverton, Steve

2006-05-01

Ursid mortality data have long been used to evaluate associations between cave-bear remains (Ursus deningeri and U. spelaeus) and hominin (Homo sp.) remains. Typically, such ursid assemblages produce mortality patterns that indicate that juvenile and old bears died during hibernation, a pattern that is used to suggest that humans and bears occupied the same caves at different times. However, a different kind of mortality pattern can also be used to suggest human influence on cave bears, particularly under circumstances when bears and humans compete for habitat. In particular, data from Lawson Cave and Jerry Long Cave, Missouri indicate that young-adult North American black bears (Ursus americanus) are prone to capture in natural-trap caves. Similar faunal data from Sima de los Huesos in Spain, where cave-bear and hominin remains are found in the same deposit, might also suggest that the bears died from falling into a natural trap. It is concluded that mortality analysis of ursid remains from caves is a useful tool with which to evaluate accumulation histories of cave deposits and relations between humans, artifacts, and cave-bear remains. In particular, ursid mortality data are relevant to the Kurtén Response, a hypothesis reiterated in the recent literature that implicates human encroachment on ursid habitat (e.g., cave den sites) as a potential cause in cave-bear extinction.

Analysis of effects of pellet-cladding bonding on trapping of the released fission gases in high burnup KKL BWR fuels

Energy Technology Data Exchange (ETDEWEB)

Brankov, Vladimir [Laboratory for Reactor Physics and Systems Behaviour at the Paul Scherrer Institute, 5232 Villigen-PSI (Switzerland); Swiss Federal Institute of Technology Lausanne (EPFL), Route Cantonale, 1015 Lausanne (Switzerland); Khvostov, Grigori; Mikityuk, Konstantin [Laboratory for Reactor Physics and Systems Behaviour at the Paul Scherrer Institute, 5232 Villigen-PSI (Switzerland); Pautz, Andreas [Laboratory for Reactor Physics and Systems Behaviour at the Paul Scherrer Institute, 5232 Villigen-PSI (Switzerland); Swiss Federal Institute of Technology Lausanne (EPFL), Route Cantonale, 1015 Lausanne (Switzerland); Restani, Renato; Abolhassani, Sousan [Laboratory for Nuclear Materials at the Paul Scherrer Institute, 5232 Villigen-PSI (Switzerland); Ledergerber, Guido [Kernkraftwerk Leibstadt, 5325 Leibstadt (Switzerland); Wiesenack, Wolfgang [Institutt for Energiteknikk - OECD Halden Reactor Project, Os Allé 5, 1777 Halden (Norway)

2016-08-15

Highlights: • Explanation for the scatter in measured fission gas release in high-BU BWR fuel rods. • Partial fuel-clad bond layer formation in high-BU BWR fuel. • Hypothesis for fission gas trapping facilitated by the pellet-cladding bond layer. • Correlation between burnup asymmetry and the quantity of trapped fission gas. • Implications of the trapped FG in LOCA transient. - Abstract: The first part of the paper presents results of a numerical analysis of the fuel behavior during base irradiation in the Kernkraftwerk Leibstadt Boiling Water Reactor (KKL BWR) using EPRI’s FALCON code coupled to GRSW-A – an advanced model for fuel swelling and fission gas release. Post-irradiation examinations conducted at the Paul Scherrer Institute’s (PSI) hot laboratory gave evidence of a distinct circumferential non-uniformity of local burnup at pellet surfaces. For several fuel samples, intact pellet-cladding bonding areas on the high burnup sides of the pellets at high burnup above ∼70 MWd/kgU were observed. It is hypothesized that a part of the fission gases, which are expected to be released by those areas, can be trapped and do not reach the rod plenum. In this paper, a simple approach to modeling of fission gas trapping is employed which reveals a potential correlation between the position of the rod within the fuel assembly (and therefore the degree of circumferential burnup non-uniformity) and the degree of fission gas trapping. A model is suggested to correlate the amount of locally trapped gas with the integral of the local contact pressure and the degree of circumferential burnup non-uniformity. The model is calibrated with available measurements of FGR from rod puncturing at the level of the plenums. In future work, the hypothesis about the axial distribution of trapped fission gas will be extrapolated to the Loss-Of-Coolant Accident (LOCA) analysis as an attempt to explain the fission gas release observed in some samples fabricated from

Astroturf seed traps for studying hydrochory

NARCIS (Netherlands)

Wolters, M; Geertsema, J; Chang, ER; Veeneklaas, RM; Carey, PD; Bakker, JP

1. Astroturf mats can effectively trap diaspores dispersed by tidal water. 2. Within four tidal inundations, up to 745 propagules per m(2) and between three and eight different species per astroturf mat were trapped. Overall, 15 different species were collected on the astroturf mats, 10 of which

Building a better sticky trap: description of an easy-to-use trap and pole mount for quantifying the abundance of adult aquatic insects

Science.gov (United States)

Smith, Joshua T.; Kennedy, Theodore A.; Muehlbauer, Jeffrey D.

2014-01-01

Insect emergence is a fundamental process in freshwaters. It is a critical life-history stage for aquatic insects and provides an important prey resource for terrestrial and aquatic consumers. Sticky traps are increasingly being used to sample these insects. The most common design consists of an acetate sheet coated with a nondrying adhesive that is attached to a wire frame or cylinder. These traps must be prepared at the deployment site, a process that can be time consuming and difficult given the vagaries of field conditions. Our goals were to develop a sturdy, low-cost sticky trap that could be prepared in advance, rapidly deployed and recovered in the field, and used to estimate the flight direction of insects. We used 150-mm Petri dishes with lids. The dishes can be coated cleanly and consistently with Tangle-Trap® adhesive. Deploying traps is simple and requires only a pole set near the body of water being sampled. Four dishes can be attached to the pole using Velcro and aligned in 4 different directions to enable quantification of insect flight direction. After sampling, Petri dishes can be taped closed, packed in boxes, and stored indefinitely. Petri traps are comparable in price to standard acetate sheet traps at ∼US$0.50/directional deployment, but they require more space for storage than acetate sheet traps. However, a major benefit of Petri traps is that field deployment times are ⅓ those of acetate traps. Our study demonstrated that large Petri dishes are an ideal platform for sampling postemergent adult aquatic insects, particularly when the study design involves estimating flight direction and when rapid deployment and recovery of traps is critical.

Quantum Information Experiments with Trapped Ions at NIST

Science.gov (United States)

Wilson, Andrew

2015-03-01

We present an overview of recent trapped-ion quantum information experiments at NIST. Advancing beyond few-qubit ``proof-of-principle'' experiments to the many-qubit systems needed for practical quantum simulation and information processing, without compromising on the performance demonstrated with small systems, remains a major challenge. One approach to scalable hardware development is surface-electrode traps. Micro-fabricated planar traps can have a number of useful features, including flexible electrode geometries, integrated microwave delivery, and spatio-temporal tuning of potentials for ion transport and spin-spin interactions. In this talk we report on a number of on-going investigations with surface traps. Experiments feature a multi-zone trap with closely spaced ions in a triangular arrangement (a first step towards 2D arrays of ions with tunable spin-spin interactions), a scheme for smooth transport through a junction in a 2D structure based on switchable RF potentials, and a micro-fabricated photo-detector integrated into a trap. We also give a progress report on our latest efforts to improve the fidelity of both optical and microwave 2-qubit gates. This work was supported by IARPA, ONR and the NIST Quantum Information Program. The 3-ion and switchable-RF-junction traps were developed in collaboration with Sandia National Laboratory.

Weak Interaction Measurements with Optically Trapped Radioactive Atoms

International Nuclear Information System (INIS)

Vieira, D.J.; Crane, S.G.; Guckert, R.; Zhao, X.; Brice, S.J.; Goldschmidt, A.; Hime, A.; Tupa, D.

1999-01-01

This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The goal of this project is to apply the latest in magneto-optical and pure magnetic trapping technology to concentrate, cool, confine, and polarize radioactive atoms for precise electroweak interaction measurements. In particular, the authors have concentrated their efforts on the trapping of 82 Rb for a parity-violating, beta-asymmetry measurement. Progress has been made in successfully trapping of up to 6 million 82 Rb(t 1/2 =75s) atoms in a magneto-optical trap coupled to a mass separator. This represents a two order of magnitude improvement in the number trapped radioactive atoms over all previous work. They have also measured the atomic hyperfine structure of 82 Rb and demonstrated the MOT-to-MOT transfer and accumulation of atoms in a second trap. Finally, they have constructed and tested a time-orbiting-potential magnetic trap that will serve as a rotating beacon of spin-polarized nuclei and a beta-telescope detection system. Prototype experiments are now underway with the initial goal of making a 1% measurements of the beta-asymmetry parameter A which would match the world's best measurements

Twin predecessor of the 2004 Indian Ocean tsunami: Implications for rebuilt coastal communities

Science.gov (United States)

Sieh, K.; Daly, P.; McKinnon, E.; Chiang, H.; Pilarczyk, J.; Daryono, M. R.; Horton, B.; Shen, C.; Rubin, C. M.; Ismail, N.; Kelsey, H. M.

2013-12-01

We present stratigraphic, historical and archeological evidence for two closely timed predecessors of the giant 2004 tsunami on the northern coast of Aceh, northern Sumatra. Beachcliff exposures reveal two beds of tsunamigenic coral rubble within a small alluvial fan. Stratigraphical consistent radiocarbon and Uranium-Thorium disequilibrium dates indicate the the two beds were emplaced in the mid- to late 14th century, correlative with paleoseismic evidence of sudden uplifts of coral reefs on nearby Simeulue island in AD 1394 and, again in AD 1450. A nearby seacliff exposure contains evidence of nearly continuous settlement from ~AD 1240 to 1367, followed by tsunami destruction. Evidence of continuous settlement included South Asian ceramic and stoneware fragments, as well as a single Chinese coin dating to AD 1111-1118. Our data may solve the mysterious 15th century discontinuity in cultures along the northern Sumatran coast of the maritime silk route. This history of a doublet tsunami has implications for communities around the Indian Ocean that were rebuilt after the devastation of 2004, since reconstruction occurred with the tacit belief that such an event would not happen in the foreseeable future. History, geology and archeology hint that such a view may prove tragically incorrect.

Trapped Mode Study in the LHC Rotatable Collimator

CERN Document Server

Xiao, L; Smith, J C; Caspers, F

2010-01-01

A rotatable collimator is proposed for the LHC phase II collimation upgrade. When the beam crosses the collimator, trapped modes will be excited that result in beam energy loss and collimator power dissipation. Some of the trapped modes can also generate transverse kick on the beam and affect the beam operation. In this paper the parallel eigensolver code Omega3P is used to search for all the trapped modes below 2GHz in the collimator, including longitudinal modes and transverse modes. The loss factors and kick factors of the trapped modes are calculated as function of the jaw positions. The amplitude ratio between transverse and longitudinal trapped mode intensity can be used as a direct measure of the position of the beam. We present simulation results and discuss the results.

The LEBIT 9.4 T Penning trap system

Energy Technology Data Exchange (ETDEWEB)

Ringle, R.; Bollen, G.; Schury, P.; Sun, T. [National Superconducting Cyclotron Laboratory, East Lansing, MI (United States); Michigan State University, Department of Physics and Astronomy, East Lansing, MI (United States); Lawton, D.; Schwarz, S. [National Superconducting Cyclotron Laboratory, East Lansing, MI (United States)

2005-09-01

The initial experimental program with the Low-Energy Beam and Ion Trap Facility, or LEBIT, will concentrate on Penning trap mass measurements of rare isotopes, delivered by the Coupled Cyclotron Facility (CCF) of the NSCL. The LEBIT Penning trap system has been optimized for high-accuracy mass measurements of very short-lived isotopes. (orig.)

The LEBIT 9.4 T Penning trap system

International Nuclear Information System (INIS)

Ringle, R.; Bollen, G.; Schury, P.; Sun, T.; Lawton, D.; Schwarz, S.

2005-01-01

The initial experimental program with the Low-Energy Beam and Ion Trap Facility, or LEBIT, will concentrate on Penning trap mass measurements of rare isotopes, delivered by the Coupled Cyclotron Facility (CCF) of the NSCL. The LEBIT Penning trap system has been optimized for high-accuracy mass measurements of very short-lived isotopes. (orig.)

Quasi-conical centrifugal ion trap

International Nuclear Information System (INIS)

Golikov, Yu.K.; Solov'ev, K.V.; Grigor'ev, D.V.; Flegontova, E.Yu.

1999-01-01

This paper describes a new excellent ion trap that principally differs from the classic hyperbolic one by its action. The action is based on the axisymmetric electrostatic quasi-conical field with the following potential type: F=F 0 [ln r - r 2 /2+z 2 ], where r, z are cylindrical dimensionless coordinates. The radial potential run (f=ln r-r 2 /2), in this case, is exactly presented by the approximation function f a =ar 2 +b/r 2 +c. In addition, there are some ranges of r (for example, 0.6< r<0.35), in which the concurrence accuracy value is above 0.5%. The paper presents the theory of particles dynamics in the centrifugal trap. Basic correlation for resolution ratios and sensitivity values are developed. Recommendations on the centrifugal trap design implementation, including the recording system, are given

EBIT trapping program

International Nuclear Information System (INIS)

Elliott, S.R.; Beck, B.; Beiersdorfer, P.; Church, D.; DeWitt, D.; Knapp, D.K.; Marrs, R.E.; Schneider, D.; Schweikhard, L.

1993-01-01

The LLNL electron beam ion trap provides the world's only source of stationary highly charged ions up to bare U. This unique capability makes many new atomic and nuclear physics experiments possible. (orig.)

Numerical evidences of universal trap-like aging dynamics

Science.gov (United States)

Cammarota, Chiara; Marinari, Enzo

2018-04-01

Trap models have been initially proposed as toy models for dynamical relaxation in extremely simplified rough potential energy landscapes. Their importance has recently grown considerably thanks to the discovery that the trap-like aging mechanism directly controls the out-of-equilibrium relaxation processes of more sophisticated spin models, that are considered as the solvable counterpart of real disordered systems. Further establishing the connection between these spin models, out-of-equilibrium behavior and the trap like aging mechanism could shed new light on the properties, which are still largely mysterious, for the activated out-of-equilibrium dynamics of disordered systems. In this work we discuss numerical evidence based on the computations of the permanence times of an emergent trap-like aging behavior in a variety of very simple disordered models—developed from the trap model paradigm. Our numerical results are backed by analytic derivations and heuristic discussions. Such exploration reveals some of the tricks needed to reveal the trap behavior in spite of the occurrence of secondary processes, of the existence of dynamical correlations and of strong finite system’s size effects.

Stratigraphic distribution of veins in the Murray and Stimson formations, Gale crater, Mars: Implications for ancient groundwater circulation

Science.gov (United States)

Nachon, M.; Sumner, D. Y.; Borges, S. R.; Stack, K.; Stein, N.; Watkins, J. A.; Banham, S.; Rivera-Hernandez, F.; Wiens, R. C.; l'Haridon, J.; Rapin, W.; Kronyak, R. E.

2017-12-01

Since landing at Gale crater, Mars, in August 2012, the Curiosity rover has driven through more than 300m of stratigraphy. From the first to the most recent sedimentary rocks explored, light-toned veins have been observed cutting the host-rock and were interpreted as diagenetic features emplaced by hydraulic fracturing. Chemical and mineralogical analyses show they consist of Ca-sulfate. Here we report on the veins' distribution within two geological formations explored more recently by the rover: (a) the Murray Formation that consists mainly of fine-grained laminated rocks that have been interpreted as having been deposited in a former lacustrine environment [1], and (b) the Stimson Formation, which lies unconformably above the Murray, and consists of cross bedded sandstones interpreted as being deposited in a aeolian environment [2]. We have performed a systematic observation of the veins within the MastCam images, from the base of the Murray (Sol 750) up to Sol 1515 [3], described their main geometrical characteristics (e.g. orientation to laminae, relative density, branching). Five veins facies were defined based on veins' geometrical properties, abundance, and host-rock grain size. The distribution of veins facies was placed within the broader stratigraphic context. The distribution of veins within the Murray and Stimson Formations shows strong rheological controls. In the Murray, light-toned veins are present from the basal part of the section up to the most recently explored exposures. Several dense vein outcrops are associated with local variations in host-rock type, suggesting rheological control of fluid circulation. In Stimson sandstones, light-toned veins are also present though much rarer, again possibly due to rheological properties. The light-toned veins represent post depositional fluid circulation, occurring after accumulation of the lacustrine Murray rocks; at least some veins formed after Murray's burial, erosion, and the deposition and

Stratigraphical distribution of the Ordovician conodont Erraticodon Dzik in Argentina

Science.gov (United States)

Heredia, S.; Carlorosi, J.; Mestre, A.; Soria, T.

2013-08-01

Three different species of the Ordovician genus Erraticodon Dzik are described and illustrated. Erraticodon patu Cooper is reported from the Lower-Midde Ordovician strata of the Acoite and Alto del Cóndor formations. E. cf. Erraticodon balticus and Erraticodon hexianensis from Middle Ordovician carbonate deposits of the San Juan Formation are analyzed and compared to specimens of these species from Australia, China, Newfoundland, and Baltica. E. patu and E. hexianensis are recorded for first time in the San Juan Formation of Precordillera. The elements of E. cf. E. balticus resemble closely E. balticus Dzik but lack the important denticle on the posterior process of the S elements. An evaluation of the stratigraphic occurrences of these species relative to those of key Lower and Middle Ordovician conodont species such as Trapezognathus diprion Lindström, Oepikodus intermedius Serpagli, Baltoniodus triangularis (Lindström), Baltoniodus navis Lindström, Yangtzeplacognathus crassus (Chen and Zhang) and Eoplacognathus pseudoplanus (Viira) indicates they value for biostratigraphic correlation.

Dynamic Trap Formation and Elimination in Colloidal Quantum Dots

KAUST Repository

Voznyy, O.; Thon, S. M.; Ip, A. H.; Sargent, E. H.

2013-01-01

Using first-principles simulations on PbS and CdSe colloidal quantum dots, we find that surface defects form in response to electronic doping and charging of the nanoparticles. We show that electronic trap states in nanocrystals are dynamic entities, in contrast with the conventional picture wherein traps are viewed as stable electronic states that can be filled or emptied, but not created or destroyed. These traps arise from the formation or breaking of atomic dimers at the nanoparticle surface. The dimers' energy levels can reside within the bandgap, in which case a trap is formed. Fortunately, we are also able to identify a number of shallow-electron-affinity cations that stabilize the surface, working to counter dynamic trap formation and allowing for trap-free doping. © 2013 American Chemical Society.

Dynamic Trap Formation and Elimination in Colloidal Quantum Dots

KAUST Repository

Voznyy, O.

2013-03-21

Using first-principles simulations on PbS and CdSe colloidal quantum dots, we find that surface defects form in response to electronic doping and charging of the nanoparticles. We show that electronic trap states in nanocrystals are dynamic entities, in contrast with the conventional picture wherein traps are viewed as stable electronic states that can be filled or emptied, but not created or destroyed. These traps arise from the formation or breaking of atomic dimers at the nanoparticle surface. The dimers\\' energy levels can reside within the bandgap, in which case a trap is formed. Fortunately, we are also able to identify a number of shallow-electron-affinity cations that stabilize the surface, working to counter dynamic trap formation and allowing for trap-free doping. © 2013 American Chemical Society.

Experiments on cold trap regeneration by NaH decomposition

International Nuclear Information System (INIS)

McPheeters, C.C.; Skladzien, S.B.; Raue, D.J.

1979-10-01

Cold trap regeneration may be very important in future LMFBRs because of the expected high hydrogen source from the steam generators. This hydrogen precipitates as NaH in the cold trap and may fill the trap within one year of operation. Several methods of cold trap regeneration were considered, but the simplest and least expensive appears to be decomposition of NaH under vacuum at elevated temperatures. Experiments were done to assess the feasibility of this method for cold trap regeneration. Small-scale simulated cold traps (SCT) were located with NaH and NaH plus Na 2 O, and were heated both under vacuum and under a sweep gas at 100 kPa. The evolved hydrogen was converted to water by a CuO bed and collected in a weighting tube

Experiments on cold-trap regeneration by NaH decomposition

International Nuclear Information System (INIS)

McPheeters, C.C.; Skladzien, S.B.; Raue, D.J.

1980-06-01

Cold-trap regeneration may be very important in future LMFBRs because of the expected high hydrogen source from the steam generators. This hydrogen precipitates as NaH in the cold trap and may fill the trap within one year of operation. Several methods of cold-trap regeneration were considered, but the simplest and least expensive appears to be decomposition of NaH under vacuum at elevated temperatures. Experiments were done to assess the feasibility of this method for cold-trap regeneration. Small-scale simulated cold traps (SCT) were loaded with NaH and NaH plus Na 2 O, and were heated both under vacuum and under a sweep gas at 100 kPa. The evolved hydrogen was converted to water by a CuO bed and collected in a weighing tube

Trapping of deuterium in krypton-implanted nickel

International Nuclear Information System (INIS)

Frank, R.C.; McManus, S.P.; Rehn, L.E.; Baldo, P.

1986-01-01

Krypton ions with energy 600 keV were implanted in nickel to fluences of 2 x 10 16 cm -2 under three different conditions. Deuterium was subsequently introduced into the implanted regions by electrolysis at room temperature. After the diffusible deuterium was permitted to escape, the 2 H( 3 He, 1 H) 4 He nuclear reaction was used to analyze for the trapped deuterium during an isochronal annealing program. The region implanted at 100 0 C with no higher temperature anneal had the largest number of traps; the region implanted at 100 0 C and annealed for 100 min at 500 0 C had considerably less; the region implanted at 500 0 C had the least. Electron diffraction patterns confirmed the existence of solid crystalline krypton in all three regions. Transmission electron microscope studies revealed precipitates with an average diameter of 8 nm in the region implanted at 500 0 C. The two regions implanted at 100 0 C contained smaller precipitates. Trap binding enthalpies were obtained by math modeling. In addition to the traps with binding enthalpy of 0.55 eV reported earlier by other investigators for helium implanted in nickel, a smaller number of traps with binding enthalpies up to 0.83 eV were also found. The trapping of deuterium by various types of imperfections, including the solid krypton precipitates, is discussed

An Experimental Analysis of Social Traps

Science.gov (United States)

Brechner, Kevin C.

1977-01-01

Social traps, such as the overgrazing of pasturelands, overpopulation, and the extinction of species, are situations where individuals in a group respond for their own advantage in a manner damaging to the group. Alaboratory analog was devised to simulate conditions that produce social traps. The intent was to cause an immediate positive…

Optical Forces on Non-Spherical Nanoparticles Trapped by Optical Waveguides

Science.gov (United States)

Hasan Ahmed, Dewan; Sung, Hyung Jin

2011-07-01

Numerical simulations of a solid-core polymer waveguide structure were performed to calculate the trapping efficiencies of particles with nanoscale dimensions smaller than the wavelength of the trapping beam. A three-dimensional (3-D) finite element method was employed to calculate the electromagnetic field. The inlet and outlet boundary conditions were obtained using an eigenvalue solver to determine the guided and evanescent mode profiles. The Maxwell stress tensor was considered for the calculation of the transverse and downward trapping efficiencies. A particle at the center of the waveguide showed minimal transverse trapping efficiency and maximal downward trapping efficiency. This trend gradually reversed as the particle moved away from the center of the waveguide. Particles with larger surface areas exhibited higher trapping efficiencies and tended to be trapped near the waveguide. Particles displaced from the wave input tended to be trapped at the waveguide surface. Simulation of an ellipsoidal particle showed that the orientation of the major axis along the waveguide's lateral z-coordinate significantly influenced the trapping efficiency. The particle dimensions along the z-coordinate were more critical than the gap distance (vertical displacement from the floor of the waveguide) between the ellipsoid particle and the waveguide. The present model was validated using the available results reported in the literature for different trapping efficiencies.

Curious behavior of optically trapped neutral atoms

International Nuclear Information System (INIS)

Wieman, C.; Walker, T.; Sesko, D.; Monroe, C.

1991-01-01

We have studied the behavior of clouds of neutral atoms contained in a spontaneous force optical trap. Because of the low temperatures of the atoms ( 5 atoms. These include the expansion of the cloud as the number is increased and dramatic changes in the distribution of the atoms at higher numbers. We can explain much of the collective behavior using a simple model that includes a 1/r 2 force between the atoms arising from the multiple scattering of photons. Finally, we discuss the optical trapping of atoms directly from a low pressure vapor in a small glass cell. We have used these optically trapped atoms to load a magnetostatic trap in the same cell. This provided a high density sample of atoms with a temperature of less than 2 μK

Paleogeographic and paleo-oceanographic influences on carbon isotope signatures: Implications for global and regional correlation, Middle-Upper Jurassic of Saudi Arabia

Science.gov (United States)

Eltom, Hassan A.; Gonzalez, Luis A.; Hasiotis, Stephen T.; Rankey, Eugene C.; Cantrell, Dave L.

2018-02-01

Carbon isotope data (δ13C) can provide an essential means for refining paleogeographic and paleo-oceanographic reconstructions, and interpreting stratigraphic architecture within complex carbonate strata. Although the primary controls on global δ13C signatures of marine carbonates are well understood, understanding their latitudinal and regional variability is poor. To better constrain the nature and applications of δ13C stratigraphy, this study: 1) presents a new high-resolution δ13C stratigraphic curve from Middle to Upper Jurassic carbonates in the upper Tuwaiq Mountain, Hanifa, and lower Jubaila formations in central Saudi Arabia; 2) explores their latitudinal and regional variability; and 3) discusses their implications for stratigraphic correlations. Analysis of δ13C data identified six mappable units with distinct δ13C signatures (units 1-6) between up-dip and down-dip sections, and one unit (unit 7) that occurs only in the down-dip section of the study succession. δ13C data from the upper Tuwaiq Mountain Formation and the lower Hanifa Formation (units 1, 2), which represent Upper Callovian to Middle Oxfordian strata, and record two broad positive δ13C excursions. In the upper part of the Hanifa Formation (units 3-6, Early Oxfordian-Late Kimmeridgian), δ13C values decreased upward to unit 7, which showed a broad positive δ13C excursion. Isotopic data suggest similar δ13C trends between the southern margin of the Tethys Ocean (Arabian Plate; low latitude, represented by the study succession) and northern Tethys oceans (high latitude), despite variations in paleoclimatic, paleogeographic, and paleoceanographic conditions. Variations in the δ13C signal in this succession can be attributed to the burial of organic matter and marine circulation at the time of deposition. Our study uses δ13C signatures to provide independent data for chronostratigraphic constraints which help in stratigraphic correlations within heterogeneous carbonate successions.

Field evaluation of a new light trap for phlebotomine sand flies.

Science.gov (United States)

Gaglio, Gabriella; Napoli, Ettore; Falsone, Luigi; Giannetto, Salvatore; Brianti, Emanuele

2017-10-01

Light traps are one of the most common attractive method for the collection of nocturnal insects. Although light traps are generally referred to as "CDC light traps", different models, equipped with incandescent or UV lamps, have been developed. A new light trap, named Laika trap 3.0, equipped with LED lamps and featured with a light and handy design, has been recently proposed into the market. In this study we tested and compared the capture performances of this new trap with those of a classical light trap model under field conditions. From May to November 2013, a Laika trap and a classical light trap were placed biweekly in an area endemic for sand flies. A total of 256 sand fly specimens, belonging to 3 species (Sergentomyia minuta, Phlebotomus perniciosus, Phlebotomus neglectus) were collected during the study period. The Laika trap captured 126 phlebotomine sand flies: P. perniciosus (n=38); S. minuta (n=88), a similar number of specimens (130) and the same species were captured by classical light trap which collected also 3 specimens of P. neglectus. No significant differences in the capture efficiency at each day of trapping, neither in the number of species or in the sex of sand flies were observed. According to results of this study, the Laika trap may be a valid alternative to classical light trap models especially when handy design and low power consumption are key factors in field studies. Copyright © 2017 Elsevier B.V. All rights reserved.

Light effect in photoionization of traps in GaN MESFETs

Directory of Open Access Journals (Sweden)

H. Arabshahi

2009-09-01

Full Text Available Trapping of hot electron behavior by trap centers located in buffer layer of a wurtzite phase GaN MESFET has been simulated using an ensemble Monte Carlo simulation. The results of the simulation show that the trap centers are responsible for current collapse in GaN MESFET at low temperatures. These electrical traps degrade the performance of the device at low temperature. On the opposite, a light-induced increase in the trap-limited drain current, results from the photoionization of trapped carriers and their return to the channel under the influence of the built in electric field associated with the trapped charge distribution. The simulated device geometries and doping are matched to the nominal parameters described for the experimental structures as closely as possible, and the predicted drain current and other electrical characteristics for the simulated device including trapping center effects show close agreement with the available experimental data.

Hydrodynamic properties and distribution of bait downstream of a zooplankton trap

DEFF Research Database (Denmark)

Selander, Erik; Heuschele, Jan; Larsson, Ann I.

2017-01-01

The flow regime around a chemically baited trap is crucial for the trapping process and distribution of bait downstream of traps. We measured the flow field downstream of a trap prototype in flume experiments and mapped the distribution of bait using laser induced fluorescence. The trap produced ...

Production of cold antihydrogen in a nested trap

International Nuclear Information System (INIS)

Fujiwara, Makoto

2004-01-01

The ATHENA experiment at CERN produced and detected the first cold antihydrogen atoms. Antiprotons and positrons are mixed in a double Penning trap, known as a nested trap. The production of antihydrogen atoms was identified by detecting their annihilations signatures at trap wall. With the ATHENA results subsequently confirmed by another CERN experiment, ATRAP, cold antihydrogen research is entering an exciting era. (author)

Traps for antimatter and antihydrogen production

International Nuclear Information System (INIS)

Holzscheiter, M.H.

1994-01-01

Even though positrons have been captured and stored in ion traps for precision measurements, the recent trapping and cooling of antiprotons may be considered as the beginning of a new era in antimatter research. For the first time all the ingredients to produce the first atom of the antimatter world, the antihydrogen atom, are at hand, and several groups have entered an active discussion on the feasibility of producing antihydrogen as well as on the possibility to perform precision tests on CPT and gravity. At the same time, the trapping of reasonable large numbers of antiprotons has opened up the way for a variety of exciting physics with ultra-low energy antiprotons, ranging from atomic physics issues to nuclear physics and medical applications. I will describe the current status of the work on trapping antiprotons and positrons, discuss possible physics applications of this technique, and describe the two most promising routes to produce antihydrogen for precision spectroscopy. Towards the end a few comments on storing the produced antihydrogen and on utilizing antihydrogen for gravity measurements and for CPT tests are given

Neutral atom traps of radioactives

International Nuclear Information System (INIS)

Behr, J.A.

2003-01-01

Neutral atoms trapped with modern laser cooling techniques offer the promise of improving several broad classes of experiments with radioactive isotopes. In nuclear β decay, neutrino spectroscopy from beta-recoil coincidences, along with highly polarized samples, enable experiments to search for non-Standard Model interactions, test whether parity symmetry is maximally violated, and search for new sources of time reversal violation. Ongoing efforts at TRIUMF, Los Alamos and Berkeley will be highlighted. The traps also offer bright sources for Doppler-free spectroscopy, particularly in high-Z atoms where precision measurements could measure the strength of weak neutral nucleon-nucleon and electron-nucleon interactions. Physics with francium atoms has been vigorously pursued at Stony Brook. Several facilities plan work with radioactive atom traps; concrete plans and efforts at KVI Groningen and Legnaro will be among those summarized. Contributions to the multidisciplinary field of trace analysis will be left up to other presenters

Neutral atom traps of radioactives

CERN Document Server

Behr, J A

2003-01-01

Neutral atoms trapped with modern laser cooling techniques offer the promise of improving several broad classes of experiments with radioactive isotopes. In nuclear beta decay, neutrino spectroscopy from beta-recoil coincidences, along with highly polarized samples, enable experiments to search for non-Standard Model interactions, test whether parity symmetry is maximally violated, and search for new sources of time reversal violation. Ongoing efforts at TRIUMF, Los Alamos and Berkeley will be highlighted. The traps also offer bright sources for Doppler-free spectroscopy, particularly in high-Z atoms where precision measurements could measure the strength of weak neutral nucleon-nucleon and electron-nucleon interactions. Physics with francium atoms has been vigorously pursued at Stony Brook. Several facilities plan work with radioactive atom traps; concrete plans and efforts at KVI Groningen and Legnaro will be among those summarized. Contributions to the multidisciplinary field of trace analysis will be left...

Trapped atoms along nanophotonic resonators

Science.gov (United States)

Fields, Brian; Kim, May; Chang, Tzu-Han; Hung, Chen-Lung

2017-04-01

Many-body systems subject to long-range interactions have remained a very challenging topic experimentally. Ultracold atoms trapped in extreme proximity to the surface of nanophotonic structures provides a dynamic system combining the strong atom-atom interactions mediated by guided mode photons with the exquisite control implemented with trapped atom systems. The hybrid system promises pair-wise tunability of long-range interactions between atomic pseudo spins, allowing studies of quantum magnetism extending far beyond nearest neighbor interactions. In this talk, we will discuss our current status developing high quality nanophotonic ring resonators, engineered on CMOS compatible optical chips with integrated nanostructures that, in combination with a side illuminating beam, can realize stable atom traps approximately 100nm above the surface. We will report on our progress towards loading arrays of cold atoms near the surface of these structures and studying atom-atom interaction mediated by photons with high cooperativity.

Glacial magnetite dissolution in abyssal NW Pacific sediments - evidence for carbon trapping?

Science.gov (United States)

Korff, Lucia; von Dobeneck, Tilo; Frederichs, Thomas; Kasten, Sabine; Kuhn, Gerhard; Gersonde, Rainer; Diekmann, Bernhard

2016-04-01

The abyssal North Pacific Ocean's large volume, depth, and terminal position on the deep oceanic conveyor make it a candidate site for deep carbon trapping as postulated by climate theory to explain the massive glacial drawdown of atmospheric CO2. As the major basins of the North Pacific have depths of 5500-6500m, far below the modern and glacial Calcite Compensation Depths (CCD), these abyssal sediments are carbonate-free and therefore not suitable for carbonate-based paleoceanographic proxy reconstructions. Instead, paleo-, rock and environmental magnetic methods are generally well applicable to hololytic abyssal muds and clays. In 2009, the international paleoceanographic research cruise SO 202 INOPEX ('Innovative North Pacific Experiment') of the German RV SONNE collected two ocean-spanning EW sediment core transects of the North Pacific and Bering Sea recovering a total of 50 piston and gravity cores from 45 sites. Out of seven here considered abyssal Northwest Pacific piston cores collected at water depths of 5100 to 5700m with mostly coherent shipboard susceptibility logs, the 20.23m long SO202-39-3, retrieved from 5102 m water depth east of northern Shatsky Rise (38°00.70'N, 164°26.78'E), was rated as the stratigraphically most promising record of the entire core transect and selected for detailed paleo- and environmental magnetic, geochemical and sedimentological investigations. This core was dated by correlating its RPI and Ba/Ti records to well-dated reference records and obviously provides a continuous sequence of the past 940 kyrs. The most striking orck magnetic features are coherent magnetite-depleted zones corresponding to glacial periods. In the interglacial sections, detrital, volcanic and even submicron bacterial magnetite fractions are excellently preserved. These alternating magnetite preservation states seem to reflect dramatic oxygenation changes in the deep North Pacific Ocean and hint at large-scale benthic glacial carbon trapping

In-trap decay spectroscopy for {beta}{beta} decays

Energy Technology Data Exchange (ETDEWEB)

Brunner, Thomas

2011-01-18

The presented work describes the implementation of a new technique to measure electron-capture (EC) branching ratios (BRs) of intermediate nuclei in {beta}{beta} decays. This technique has been developed at TRIUMF in Vancouver, Canada. It facilitates one of TRIUMF's Ion Traps for Atomic and Nuclear science (TITAN), the Electron Beam Ion Trap (EBIT) that is used as a spectroscopy Penning trap. Radioactive ions, produced at the radioactive isotope facility ISAC, are injected and stored in the spectroscopy Penning trap while their decays are observed. A key feature of this technique is the use of a strong magnetic field, required for trapping. It radially confines electrons from {beta} decays along the trap axis while X-rays, following an EC, are emitted isotropically. This provides spatial separation of X-ray and {beta} detection with almost no {beta}-induced background at the X-ray detector, allowing weak EC branches to be measured. Furthermore, the combination of several traps allows one to isobarically clean the sample prior to the in-trap decay spectroscopy measurement. This technique has been developed to measure ECBRs of transition nuclei in {beta}{beta} decays. Detailed knowledge of these electron capture branches is crucial for a better understanding of the underlying nuclear physics in {beta}{beta} decays. These branches are typically of the order of 10{sup -5} and therefore difficult to measure. Conventional measurements suffer from isobaric contamination and a dominating {beta} background at theX-ray detector. Additionally, X-rays are attenuated by the material where the radioactive sample is implanted. To overcome these limitations, the technique of in-trap decay spectroscopy has been developed. In this work, the EBIT was connected to the TITAN beam line and has been commissioned. Using the developed beam diagnostics, ions were injected into the Penning trap and systematic studies on injection and storage optimization were performed. Furthermore, Ge

In-trap decay spectroscopy for ββ decays

International Nuclear Information System (INIS)

Brunner, Thomas

2011-01-01

The presented work describes the implementation of a new technique to measure electron-capture (EC) branching ratios (BRs) of intermediate nuclei in ββ decays. This technique has been developed at TRIUMF in Vancouver, Canada. It facilitates one of TRIUMF's Ion Traps for Atomic and Nuclear science (TITAN), the Electron Beam Ion Trap (EBIT) that is used as a spectroscopy Penning trap. Radioactive ions, produced at the radioactive isotope facility ISAC, are injected and stored in the spectroscopy Penning trap while their decays are observed. A key feature of this technique is the use of a strong magnetic field, required for trapping. It radially confines electrons from β decays along the trap axis while X-rays, following an EC, are emitted isotropically. This provides spatial separation of X-ray and β detection with almost no β-induced background at the X-ray detector, allowing weak EC branches to be measured. Furthermore, the combination of several traps allows one to isobarically clean the sample prior to the in-trap decay spectroscopy measurement. This technique has been developed to measure ECBRs of transition nuclei in ββ decays. Detailed knowledge of these electron capture branches is crucial for a better understanding of the underlying nuclear physics in ββ decays. These branches are typically of the order of 10 -5 and therefore difficult to measure. Conventional measurements suffer from isobaric contamination and a dominating β background at theX-ray detector. Additionally, X-rays are attenuated by the material where the radioactive sample is implanted. To overcome these limitations, the technique of in-trap decay spectroscopy has been developed. In this work, the EBIT was connected to the TITAN beam line and has been commissioned. Using the developed beam diagnostics, ions were injected into the Penning trap and systematic studies on injection and storage optimization were performed. Furthermore, Ge detectors, for the detection of X-rays, were

CORE-BASED INTEGRATED SEDIMENTOLOGIC, STRATIGRAPHIC, AND GEOCHEMICAL ANALYSIS OF THE OIL SHALE BEARING GREEN RIVER FORMATION, UINTA BASIN, UTAH

Energy Technology Data Exchange (ETDEWEB)

Lauren P. Birgenheier; Michael D. Vanden Berg,

2011-04-11

An integrated detailed sedimentologic, stratigraphic, and geochemical study of Utah's Green River Formation has found that Lake Uinta evolved in three phases (1) a freshwater rising lake phase below the Mahogany zone, (2) an anoxic deep lake phase above the base of the Mahogany zone and (3) a hypersaline lake phase within the middle and upper R-8. This long term lake evolution was driven by tectonic basin development and the balance of sediment and water fill with the neighboring basins, as postulated by models developed from the Greater Green River Basin by Carroll and Bohacs (1999). Early Eocene abrupt global-warming events may have had significant control on deposition through the amount of sediment production and deposition rates, such that lean zones below the Mahogany zone record hyperthermal events and rich zones record periods between hyperthermals. This type of climatic control on short-term and long-term lake evolution and deposition has been previously overlooked. This geologic history contains key points relevant to oil shale development and engineering design including: (1) Stratigraphic changes in oil shale quality and composition are systematic and can be related to spatial and temporal changes in the depositional environment and basin dynamics. (2) The inorganic mineral matrix of oil shale units changes significantly from clay mineral/dolomite dominated to calcite above the base of the Mahogany zone. This variation may result in significant differences in pyrolysis products and geomechanical properties relevant to development and should be incorporated into engineering experiments. (3) This study includes a region in the Uinta Basin that would be highly prospective for application of in-situ production techniques. Stratigraphic targets for in-situ recovery techniques should extend above and below the Mahogany zone and include the upper R-6 and lower R-8.

Cryptography, quantum computation and trapped ions

Energy Technology Data Exchange (ETDEWEB)

Hughes, Richard J.

1998-03-01

The significance of quantum computation for cryptography is discussed. Following a brief survey of the requirements for quantum computational hardware, an overview of the ion trap quantum computation project at Los Alamos is presented. The physical limitations to quantum computation with trapped ions are analyzed and an assessment of the computational potential of the technology is made.

Bait preference in basket trap fishing operation and heavy metal ...

African Journals Online (AJOL)

The bait preference of basket traps fishing operation and heavy metal contamination in the trap catches from Lagos Lagoon were carried out between January and June 2011. Sixty baskets traps were used for the fishing operation, twenty basket traps were baited each with soap, coconut and maize. Clibanarius africanus ...

Trapped field recovery of bulk superconductor magnets by static field magnetization

Energy Technology Data Exchange (ETDEWEB)

Deng, Z., E-mail: zigang@kaiyodai.ac.jp [Laboratory of Applied Physics, Department of Marine Electronics and Mechanical Engineering, Tokyo University of Marine Science and Technology, Tokyo 135-8533 (Japan); Tsuzuki, K.; Miki, M.; Felder, B.; Hara, S.; Izumi, M. [Laboratory of Applied Physics, Department of Marine Electronics and Mechanical Engineering, Tokyo University of Marine Science and Technology, Tokyo 135-8533 (Japan)

2011-11-15

A series of initial trapped fields after ZFC or FC magnetization are used to simulate the attenuated trapped field. It is possible and easy to recover the lost trapped field and regain the best trapped field performance as before. In the re-magnetization process, the initial magnetic flux inside the bulk magnets will help to recover the trapped field. The optimum recovery field is recommended to be 2.5 times the saturation field of the bulk at LN2 temperature. Thanks to the trapped field of bulk high-temperature superconductors, they can be used as field-pole magnets in the high temperature superconducting (HTS) rotating machines. For example, an output power of 10 kW at 720 rpm was realized by an average trapped field of 0.56 T of eight melt-textured GdBa{sub 2}Cu{sub 3}O{sub y} (Gd-123) bulks at liquid nitrogen temperature in TUMSAT in 2004. Similarly to the HTS machines involving 1G or 2G wires, the trapped field of the bulk is possibly sensitive and even can be attenuated by the AC component field during the operation. Hence, it is necessary to recover the trapped field once being decreased to some extent in the practical application. From this point, we have investigated the trapped field recovery of HTS bulk magnets by static field magnetization in the paper. A series of different initial trapped fields after zero-field-cooling or field-cooling magnetization are used to simulate the attenuated trapped field. By comparing the trapped field peak and its distribution, the trapped field was found to be able to recover by the static field magnetization method with a stronger excitation field and the initial trapped flux inside the bulk also has an influence on the recovery process. The optimum recovery field was found to be about 2.5 times the saturated trapped field of the bulk at liquid nitrogen temperature, by which the bulk can regain the former best trapped field performance.

Optimising camera traps for monitoring small mammals.

Directory of Open Access Journals (Sweden)

Alistair S Glen

Full Text Available Practical techniques are required to monitor invasive animals, which are often cryptic and occur at low density. Camera traps have potential for this purpose, but may have problems detecting and identifying small species. A further challenge is how to standardise the size of each camera's field of view so capture rates are comparable between different places and times. We investigated the optimal specifications for a low-cost camera trap for small mammals. The factors tested were 1 trigger speed, 2 passive infrared vs. microwave sensor, 3 white vs. infrared flash, and 4 still photographs vs. video. We also tested a new approach to standardise each camera's field of view. We compared the success rates of four camera trap designs in detecting and taking recognisable photographs of captive stoats (Mustelaerminea, feral cats (Felis catus and hedgehogs (Erinaceuseuropaeus. Trigger speeds of 0.2-2.1 s captured photographs of all three target species unless the animal was running at high speed. The camera with a microwave sensor was prone to false triggers, and often failed to trigger when an animal moved in front of it. A white flash produced photographs that were more readily identified to species than those obtained under infrared light. However, a white flash may be more likely to frighten target animals, potentially affecting detection probabilities. Video footage achieved similar success rates to still cameras but required more processing time and computer memory. Placing two camera traps side by side achieved a higher success rate than using a single camera. Camera traps show considerable promise for monitoring invasive mammal control operations. Further research should address how best to standardise the size of each camera's field of view, maximise the probability that an animal encountering a camera trap will be detected, and eliminate visible or audible cues emitted by camera traps.

Experimental apparatus to test air trap valves

Science.gov (United States)

Lemos De Lucca, Y. de F.; de Aquino, G. A.; Filho, J. G. D.

2010-08-01

It is known that the presence of trapped air within water distribution pipes can lead to irregular operation or even damage to the distribution systems and their components. The presence of trapped air may occur while the pipes are being filled with water, or while the pumping systems are in operation. The formation of large air pockets can produce the water hammer phenomenon, the instability and the loss of pressure in the water distribution networks. As a result, it can overload the pumps, increase the consumption of electricity, and damage the pumping system. In order to avoid its formation, all of the trapped air should be removed through "air trap valves". In Brazil, manufacturers frequently have unreliable sizing charts, which cause malfunctioning of the "air trap valves". The result of these malfunctions causes accidents of substantial damage. The construction of a test facility will provide a foundation of technical information that will be used to help make decisions when designing a system of pipelines where "air trap valves" are used. To achieve this, all of the valve characteristics (geometric, mechanic, hydraulic and dynamic) should be determined. This paper aims to describe and analyze the experimental apparatus and test procedure to be used to test "air trap valves". The experimental apparatus and test facility will be located at the University of Campinas, Brazil at the College of Civil Engineering, Architecture, and Urbanism in the Hydraulics and Fluid Mechanics laboratory. The experimental apparatus will be comprised of various components (pumps, steel pipes, butterfly valves to control the discharge, flow meter and reservoirs) and instrumentation (pressure transducers, anemometer and proximity sensor). It should be emphasized that all theoretical and experimental procedures should be defined while taking into consideration flow parameters and fluid properties that influence the tests.

Experimental apparatus to test air trap valves

Energy Technology Data Exchange (ETDEWEB)

Lemos De Lucca, Y de F [CTH-DAEE-USP/FAAP/UNICAMP (Brazil); Aquino, G A de [SABESP/UNICAMP (Brazil); Filho, J G D, E-mail: yvone.lucca@gmail.co [Water Resources Department, University of Campinas-UNICAMP, Av. Albert Einstein, 951, Cidade Universitaria-Barao Geraldo-Campinas, S.P., 13083-852 (Brazil)

2010-08-15

It is known that the presence of trapped air within water distribution pipes can lead to irregular operation or even damage to the distribution systems and their components. The presence of trapped air may occur while the pipes are being filled with water, or while the pumping systems are in operation. The formation of large air pockets can produce the water hammer phenomenon, the instability and the loss of pressure in the water distribution networks. As a result, it can overload the pumps, increase the consumption of electricity, and damage the pumping system. In order to avoid its formation, all of the trapped air should be removed through 'air trap valves'. In Brazil, manufacturers frequently have unreliable sizing charts, which cause malfunctioning of the 'air trap valves'. The result of these malfunctions causes accidents of substantial damage. The construction of a test facility will provide a foundation of technical information that will be used to help make decisions when designing a system of pipelines where 'air trap valves' are used. To achieve this, all of the valve characteristics (geometric, mechanic, hydraulic and dynamic) should be determined. This paper aims to describe and analyze the experimental apparatus and test procedure to be used to test 'air trap valves'. The experimental apparatus and test facility will be located at the University of Campinas, Brazil at the College of Civil Engineering, Architecture, and Urbanism in the Hydraulics and Fluid Mechanics laboratory. The experimental apparatus will be comprised of various components (pumps, steel pipes, butterfly valves to control the discharge, flow meter and reservoirs) and instrumentation (pressure transducers, anemometer and proximity sensor). It should be emphasized that all theoretical and experimental procedures should be defined while taking into consideration flow parameters and fluid properties that influence the tests.

Commissioning of the double Penning trap system MLLTRAP

International Nuclear Information System (INIS)

Kolhinen, V.S.; Bussmann, M.; Gartzke, E.; Habs, D.; Neumayr, J.B.; Schuermann, C.; Szerypo, J.; Thirolf, P.G.

2009-01-01

A cylindrical double Penning trap system has been installed and commissioned at the Maier-Leibnitz-Laboratory (MLL) in Garching. This trap system has been designed to isobarically purify low-energy ion beams and perform highly accurate mass measurements. Technical details of the device and the first results of the commissioning measurements will be presented. The mass resolving power achieved in the first trap for 85 Rb ions is R=139(2)x10 3 , while a relative mass uncertainty of δm/m=2.9x10 -8 was reached with the second trap (no analysis of systematic uncertainties included) when using 87 Rb as a reference ion for 85 Rb.

Defect trapping of deuterium implanted in aluminium

International Nuclear Information System (INIS)

Kido, Y.; Kakeno, M.; Yamada, K.; Hioki, T.; Kawamoto, J.

1982-01-01

The behaviour of deuterium implanted in Al was studied by the D( 3 He,p) 4 He and the D(d,p)T nuclear reactions. Changes of the depth profiles of the deuterium after heat treatments indicated that the implanted deuterium was trapped by the defect produced during the deuterium implantation and the release probability of the trapped deuterium increased as the specimen temperature was raised. Assuming a thermal equilibrium locally in the region of high defect concentration, the trapping energy of deuterium in Al was determined to be 0.12eV. Since the release probability for the single crystal was considerably larger than that for the polycrystal specimens, the deuterium was considered to be strongly trapped in the grain boundaries. Distributions of displaced Al atoms and the recovery of the lattice damage by annealing were measured by the channelling technique. (author)

Whistler wave trapping in a density crest

International Nuclear Information System (INIS)

Sugai, H.; Niki, H.; Inutake, M.; Takeda, S.

1979-11-01

The linear trapping process of whistler waves in a field-aligned density crest is investigated theoretically and experimentally below ω = ωsub(c)/2 (half gyrofrequency). The conditions of the crest trapping are derived in terms of the frequency ω/ωsub(c), the incident wave-normal angle theta sub(i), and the density ratio n sub(i)/n sub(o), where n sub(i) and n sub(o) denote the density at the incident point and that at the ridge, respectively. The oscillation length of the trapped ray path is calculated for a parabolic density profile. The experiment on antenna-excited whistler wave has been performed in a large magnetized plasma with the density crest. The phase and amplitude profile of the whistler wave is measured along and across the crest. The measurement has verified characteristic behaviors of the crest trapping. (author)

Development of medfly female attractant systems for trapping in Spain

International Nuclear Information System (INIS)

Ros, J.P.

1999-01-01

This report contains information from a four-year research programme co-ordinated by the International Atomic Energy Agency. The objective of the programme was to develop a trapping system for females of the Mediterranean fruit fly (medfly), Ceratitis capitata (Diptera: Tephritidae), for practical use in Sterile Insect Technique (SIT) programs and to design and evaluate a trap to obtain eggs from wild female medflies in order to estimate sterility induction in the field population. Spain (through INIA) participated in this programme because of interest in the control of medfly in this area of the Mediterranean. Citrus, peaches, plums, apricots and other subtropical fruits are some of the cultures which are severely attacked by this pest. To facilitate comparison of results, all the trials of 1994 - 97 were carried out in the same orchards. These orchards were located near the Malaga airport in the south of Spain on the Mediterranean coast. Female medfly attractants tested were three food based 'female' attractants (FA-3), namely ammonium acetate (AA), 1,4 diaminobutane (putrescine) and trimethylamine, all formulated to last at least one month. These attractants were evaluated either in combinations of two (AA + putrescine, termed FA-2) or all three (termed FA-3). The attractants were tested in various traps including the plastic International Pheromone's McPhail traps (IPMT) and Tephri traps, a Spanish trap similar to the IPMT. Traps were used either as a dry trap (provided with DDVP) or a wet trap (provided with water and 0.01% surfactant). Jackson traps with Trimedlure JT,TML), a routinely used male medfly trapping system, was also used. Based on the results of successive years, we can observe progress towards the project goals. In 1994, the development of the FA-2 attractants (P+AA) with their selectivity for female medflies was a significant effort towards reaching future goals. The synergism of trimethylamine with the FA-2 attractants, yielding the FA-3

Trapping of Rift Valley Fever (RVF vectors using Light Emitting Diode (LED CDC traps in two arboviral disease hot spots in Kenya

Directory of Open Access Journals (Sweden)

Tchouassi David P

2012-05-01

Full Text Available Abstract Background Mosquitoes’ response to artificial lights including color has been exploited in trap designs for improved sampling of mosquito vectors. Earlier studies suggest that mosquitoes are attracted to specific wavelengths of light and thus the need to refine techniques to increase mosquito captures following the development of super-bright light-emitting diodes (LEDs which emit narrow wavelengths of light or very specific colors. Therefore, we investigated if LEDs can be effective substitutes for incandescent lamps used in CDC light traps for mosquito surveillance, and if so, determine the best color for attraction of important Rift Valley Fever (RFV vectors. Methods The efficiency of selected colored LED CDC light traps (red, green, blue, violet, combination of blue-green-red (BGR to sample RVF vectors was evaluated relative to incandescent light (as control in a CDC light trap in two RVF hotspots (Marigat and Ijara districts in Kenya. In field experiments, traps were baited with dry ice and captures evaluated for Aedes tricholabis, Ae. mcintoshi, Ae. ochraceus, Mansonia uniformis, Mn. africana and Culex pipiens, following Latin square design with days as replicates. Daily mosquito counts per treatment were analyzed using a generalized linear model with Negative Binomial error structure and log link using R. The incidence rate ratios (IRR that mosquito species chose other treatments instead of the control, were estimated. Results Seasonal preference of Ae.mcintoshi and Ae. ochraceus at Ijara was evident with a bias towards BGR and blue traps respectively in one trapping period but this pattern waned during another period at same site with significantly low numbers recorded in all colored traps except blue relative to the control. Overall results showed that higher captures of all species were recorded in control traps compared to the other LED traps (IRR  Conclusion Based on our trapping design and color, none of the LEDs

Photonic crystals for light trapping in solar cells

Energy Technology Data Exchange (ETDEWEB)

Gjessing, Jo

2012-07-25

Solar energy is an abundant and non-polluting source of energy. Nevertheless, the installation of solar cells for energy production is still dependent on subsidies in most parts of the world. One way of reducing the costs of solar cells is to decrease their thickness. This will reduce material consumption and, at the same time, unlock the possibility of using cheaper lower quality solar cell material. However, a thinner solar cell will have a higher optical loss due to insufficient absorption of long wavelength light. Therefore, light-trapping must be improved in order to make thin solar cells economically viable. In this thesis I investigate the potential for light-trapping in thin silicon solar cells by the use of various photonic crystal back-side structures. The first structure I study consists of a periodic array of cylinders in a configuration with a layer of silicon oxide separating the periodic structure from the rear metal reflector. This configuration reduces unwanted parasitic absorption in the reflector and the thickness of the oxide layer provides a new degree of freedom for improving light trapping from the structure. I use a large-period and a small-period approximation to analyze the cylinder structure and to identify criteria that contributes to successful light-trapping. I explore the light-trapping potential of various periodic structures including dimples, inverted pyramids, and cones. The structures are compared in an optical model using a 20 m thick Si slab. I find that the light trapping potential differs between the structures, that the unit cell dimensions for the given structure is more important for light trapping than the type of structure, and that the optimum lattice period does not differ significantly between the different structures. The light-trapping effect of the structures is investigated as a function on incidence angle. The structures provide good light trapping also under angles of incidence up to 60 degrees. The behavior

Photonic crystals for light trapping in solar cells

International Nuclear Information System (INIS)

Gjessing, Jo

2012-01-01

Solar energy is an abundant and non-polluting source of energy. Nevertheless, the installation of solar cells for energy production is still dependent on subsidies in most parts of the world. One way of reducing the costs of solar cells is to decrease their thickness. This will reduce material consumption and, at the same time, unlock the possibility of using cheaper lower quality solar cell material. However, a thinner solar cell will have a higher optical loss due to insufficient absorption of long wavelength light. Therefore, light-trapping must be improved in order to make thin solar cells economically viable. In this thesis I investigate the potential for light-trapping in thin silicon solar cells by the use of various photonic crystal back-side structures. The first structure I study consists of a periodic array of cylinders in a configuration with a layer of silicon oxide separating the periodic structure from the rear metal reflector. This configuration reduces unwanted parasitic absorption in the reflector and the thickness of the oxide layer provides a new degree of freedom for improving light trapping from the structure. I use a large-period and a small-period approximation to analyze the cylinder structure and to identify criteria that contributes to successful light-trapping. I explore the light-trapping potential of various periodic structures including dimples, inverted pyramids, and cones. The structures are compared in an optical model using a 20 m thick Si slab. I find that the light trapping potential differs between the structures, that the unit cell dimensions for the given structure is more important for light trapping than the type of structure, and that the optimum lattice period does not differ significantly between the different structures. The light-trapping effect of the structures is investigated as a function on incidence angle. The structures provide good light trapping also under angles of incidence up to 60 degrees. The behavior

Local condensate depletion at trap center under strong interactions

Science.gov (United States)

Yukalov, V. I.; Yukalova, E. P.

2018-04-01

Cold trapped Bose-condensed atoms, interacting via hard-sphere repulsive potentials are considered. Simple mean-field approximations show that the condensate distribution inside a harmonic trap always has the shape of a hump with the maximum condensate density occurring at the trap center. However, Monte Carlo simulations at high density and strong interactions display the condensate depletion at the trap center. The explanation of this effect of local condensate depletion at trap center is suggested in the frame of self-consistent theory of Bose-condensed systems. The depletion is shown to be due to the existence of the anomalous average that takes into account pair correlations and appears in systems with broken gauge symmetry.

Reefs of the Jurassic-Cretaceous west Atlantic margin : an overview of settings, types, facies trends, depositional styles and terminations (with reservoir implications)

Energy Technology Data Exchange (ETDEWEB)

Eliuk, L.S. [GeoTours Consulting Inc., Calgary, AB (Canada)

2005-07-01

In the past 40 years, approximately 20 exploratory wells have been drilled in the Jurassic-Cretaceous Abenaki Formation near-margin carbonate sequences off the Atlantic coast. These include the pioneer wells drilled in the 1970s offshore Nova Scotia, a mid-1980s group including 3 Baltimore Canyon wells in the United States, and those following EnCana's Deep Panuke 1998 gas discovery offshore Nova Scotia. A comparison of these wells has revealed 2 margin settings over deep basement highs versus prograded carbonates, 3 reef-reef mound/slope types, and an overall vertical facies trend that reveals an upward progression from microbial-rich slope beds to shallower forereef to reef and reef-flat beds initially rich in coralline sponges, followed by more microsolenid corals and bioeroded stormreworked coral-rich and oncolitic debris beds up to oolitic shoals. The top of carbonate bank sequences may be replaced gradually by shallow-water siliciclastics near deltaic depocentres or abruptly by deeper-water sponge-reef-derived beds. Smaller-scale similar flooding and shoaling patterns exist within this overall style that allow sequence or parasequence subdivision in Nova Scotia following an initial oolitic flooding event immediately above the Misaine shale. The association of deltas and reef termination suggests drowning by nutrient poisoning. The mid-Mesozoic biotas appear more robust by living in close proximity to siliciclastics. Being at the carbonate shelf margin and in a non-argillaceous shallow water reef-associated facies would appear to be necessary requirements for gas-bearing reservoir development in the Abenaki, but they are not sufficient. Originally porous oolitic grainstones are tight in areas where they are deeply buried in the Panuke area. Siliciclastic burial influenced the limestone cementation, resulting in potential stratigraphic trapping where offset by subsurface dolomitization and leaching fed by fractures or faults in coarser reef

Studies of torsional properties of DNA and nucleosomes using angular optical trapping

Science.gov (United States)

Sheinin, Maxim Y.

DNA in vivo is subjected to torsional stress due to the action of molecular motors and other DNA-binding proteins. Several decades of research have uncovered the fascinating diversity of DNA transformations under torsion and the important role they play in the regulation of vital cellular processes such as transcription and replication. Recent studies have also suggested that torsion can influence the structure and stability of nucleosomes---basic building blocks of the eukaryotic genome. However, our understanding of the impact of torsion is far from being complete due to significant experimental challenges. In this work we have used a powerful single-molecule experimental technique, angular optical trapping, to address several long-standing issues in the field of DNA and nucleosome mechanics. First, we utilized the high resolution and direct torque measuring capability of the angular optical trapping to precisely measure DNA twist-stretch coupling. Second, we characterized DNA melting under tension and torsion. We found that torsionally underwound DNA forms a left-handed structure, significantly more flexible compared to the regular B-DNA. Finally, we performed the first comprehensive investigation of the single nucleosome behavior under torque and force. Importantly, we discovered that positive torque causes significant dimer loss, which can have implications for transcription through chromatin.

Geomorphologic, stratigraphic and sedimentologic evidences of tectonic activity in Sone-Ganga alluvial tract in Middle Ganga Plain, India

Science.gov (United States)

Sahu, Sudarsan; Saha, Dipankar

2014-08-01

The basement of the Ganga basin in the Himalayan foreland is criss-crossed by several faults, dividing the basin into several sub-blocks forming horsts, grabens, or half-grabens. Tectonic perturbations along basement faults have affected the fluvial regime and extent of sediment fill in different parts of the basin during Late Quaternary. The East Patna Fault (EPF) and the West Patna Fault (WPF), located in Sone-Ganga alluvial tract in the southern marginal parts of Middle Ganga Plain (MGP), have remained tectonically active. The EPF particularly has acted significantly and influenced in evolving the geomorphological landscape and the stratigraphic architecture of the area. The block bounded by the two faults has earlier been considered as a single entity, constituting a half-graben. The present investigation (by morpho-stratigraphic and sedimentologic means) has revealed the existence of yet another fault within the half-graben, referred to as Bishunpur-Khagaul Fault (BKF). Many of the long profile morphological characters (e.g., knick-zone, low width-depth ratio) of the Sone River at its lower reaches can be ascribed to local structural deformation along BKF. These basement faults in MGP lie parallel to each other in NE-SW direction.

Preliminary stratigraphic and hydrogeologic cross sections and seismic profile of the Floridan aquifer system of Broward County, Florida

Science.gov (United States)

Reese, Ronald S.; Cunningham, Kevin J.

2013-01-01

To help water-resource managers evaluate the Floridan aquifer system (FAS) as an alternative water supply, the U.S. Geological Survey initiated a study, in cooperation with the Broward County Environmental Protection and Growth Management Department, to refine the hydrogeologic framework of the FAS in the eastern part of Broward County. This report presents three preliminary cross sections illustrating stratigraphy and hydrogeology in eastern Broward County as well as an interpreted seismic profile along one of the cross sections. Marker horizons were identified using borehole geophysical data and were initially used to perform well-to-well correlation. Core sample data were integrated with the borehole geophysical data to support stratigraphic and hydrogeologic interpretations of marker horizons. Stratigraphic and hydrogeologic units were correlated across the county using borehole geophysical data from multiple wells. Seismic-reflection data were collected along the Hillsboro Canal. Borehole geophysical data were used to identify and correlate hydrogeologic units in the seismic-reflection profile. Faults and collapse structures that intersect hydrogeologic units were also identified in the seismic profile. The information provided in the cross sections and the seismic profile is preliminary and subject to revision.

Modes of oscillation in radiofrequency Paul traps

DEFF Research Database (Denmark)

Landa, H.; Reznik, B.; Drewsen, M.

2012-01-01

We examine the time-dependent dynamics of ion crystals in radiofrequency traps. The problem of stable trapping of general threedimensional crystals is considered and the validity of the pseudopotential approximation is discussed. We analytically derive the micromotion amplitude of the ions...

Evaluation of chromatic cues for trapping Bactrocera tau.

Science.gov (United States)

Li, Lei; Ma, Huabo; Niu, Liming; Han, Dongyin; Zhang, Fangping; Chen, Junyu; Fu, Yueguan

2017-01-01

Trapping technology based on chromatic cues is an important strategy in controlling Tephritidae (fruit flies). The objectives of this present study were to evaluate the preference of Bactrocera tau for different chromatic cues, and to explore an easy method to print and reproduce coloured paper. Chromatic cues significantly affected the preference of adult B. tau. Wavelengths in the 515-604 nm range were the suitable wavelengths for trapping B. tau. Different-day-old B. tau had different colour preferences. Virtual wavelengths of 595 nm (yellow) and 568 nm (yellowish green) were the optimum wavelengths for trapping 5-7-day-old B. tau and 30-32-day-old B. tau respectively. The trap type and height significantly influenced B. tau attraction efficiency. The number of B. tau on coloured traps hung perpendicular to plant rows was not significantly higher than the number on traps hung parallel to plant rows. The quantisation of colour on the basis of Bruton's wavelength to RGB function can serve as an alternative method for printing and reproducing coloured paper, but a corrected equation should be established between the theoretical wavelength and actual wavelength of coloured paper. Results show that a compound paper coloured yellow (595 nm) and yellowish green (568 nm) installed at 60 and 90 cm above the ground shows the maximum effect for trapping B. tau. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Out-of-equilibrium dynamics in a Gaussian trap model

International Nuclear Information System (INIS)

Diezemann, Gregor

2007-01-01

The violations of the fluctuation-dissipation theorem are analysed for a trap model with a Gaussian density of states. In this model, the system reaches thermal equilibrium for long times after a quench to any finite temperature and therefore all ageing effect are of a transient nature. For not too long times after the quench it is found that the so-called fluctuation-dissipation ratio tends to a non-trivial limit, thus indicating the possibility for the definition of a timescale-dependent effective temperature. However, different definitions of the effective temperature yield distinct results. In particular, plots of the integrated response versus the correlation function strongly depend on the way they are constructed. Also the definition of effective temperatures in the frequency domain is not unique for the model considered. This may have some implications for the interpretation of results from computer simulations and experimental determinations of effective temperatures

Antihydrogen Formation, Dynamics and Trapping

CERN Document Server

Butler, Eoin; Charlton, Michael

2011-01-01

Antihydrogen, the simplest pure-antimatter atomic system, holds the promise of direct tests of matter-antimatter equivalence and CPT invariance, two of the outstanding unanswered questions in modern physics. Antihydrogen is now routinely produced in charged-particle traps through the combination of plasmas of antiprotons and positrons, but the atoms escape and are destroyed in a minuscule fraction of a second. The focus of this work is the production of a sample of cold antihydrogen atoms in a magnetic atom trap. This poses an extreme challenge, because the state-of-the-art atom traps are only approximately 0.5 K deep for ground-state antihydrogen atoms, much shallower than the energies of particles stored in the plasmas. This thesis will outline the main parts of the ALPHA experiment, with an overview of the important physical processes at work. Antihydrogen production techniques will be described, and an analysis of the spatial annihilation distribution to give indications of the temperature and binding ene...

Description of the IMR Standard Light Trap and the Vertical ...

African Journals Online (AJOL)

The construction of different versions of a cheap, robust, and easy to operate light trap for catching various aquatic organisms is shown. The trap can be used to > 300 m depth and meets a number of criteria. Small-scale vertical distribution of decapod larvae was investigated during trap trials. The traps (6-10) were set for 24 ...

Mosquito Traps: An Innovative, Environmentally Friendly Technique to Control Mosquitoes

Directory of Open Access Journals (Sweden)

Brigitte Poulin

2017-03-01

Full Text Available We tested the use of mosquito traps as an alternative to spraying insecticide in Camargue (France following the significant impacts observed on the non-target fauna through Bti persistence and trophic perturbations. In a village of 600 inhabitants, 16 Techno Bam traps emitting CO2 and using octenol lures were set from April to November 2016. Trap performance was estimated at 70% overall based on mosquitoes landing on human bait in areas with and without traps. The reduction of Ochlerotatus caspius and Oc. detritus, the two species targeted by Bti spraying, was, respectively, 74% and 98%. Traps were less efficient against Anopheles hyrcanus (46%, which was more attracted by lactic acid than octenol lures based on previous tests. Nearly 300,000 mosquitoes from nine species were captured, with large variations among traps, emphasizing that trap performance is also influenced by surrounding factors. Environmental impact, based on the proportion of non-target insects captured, was mostly limited to small chironomids attracted by street lights. The breeding success of a house martin colony was not significantly affected by trap use, in contrast to Bti spraying. Our experiment confirms that the deployment of mosquito traps can offer a cost-effective alternative to Bti spraying for protecting local populations from mosquito nuisance in sensitive natural areas.

Effect of trapping on transport coherence

International Nuclear Information System (INIS)

Barvik, I.; Herman, P.

1990-10-01

Influence of a trap (sink) on an exciton transfer in molecular aggregates is investigated. Memory functions entering the generalized master equations are calculated. The presence of the sink changes their analytical form. We used the sink in trimer as example to show that for large trapping rate parameters the rest of the system is decoupled from the sink. (author). 8 refs, 2 figs

Trapped ion depletion by anomalous diffusion due to the dissipative trapped ion instability

International Nuclear Information System (INIS)

Wimmel, H.K.

1975-07-01

At high temperatures the KADOMTSEV-POGUTSE diffusion in tokamaks can become so large as to cause depletion of trapped ions if these are replaced with free ions by means of collisions rather than being directly recycled or injected. Modified KADOMTSEV-POGUTSE diffusion formulas are employed in order to estimate this effect in the cases of classical and anomalous collisions. The maximum trapped-ion depletion is estimated from the PENROSE stability condition. For anomalous collisions a BOHM-type diffusion is derived. Numerical examples are given for JET-like parameters (JET = Joint European Torus). Depletion is found to reduce diffusion by factors of up to 10 and more. (orig.) [de

A versatile electrostatic trap with open optical access

Science.gov (United States)

Li, Sheng-Qiang; Yin, Jian-Ping

2018-04-01

A versatile electrostatic trap with open optical access for cold polar molecules in weak-field-seeking state is proposed in this paper. The trap is composed of a pair of disk electrodes and a hexapole. With the help of a finite element software, the spatial distribution of the electrostatic field is calculated. The results indicate that a three-dimensional closed electrostatic trap is formed. Taking ND3 molecules as an example, the dynamic process of loading and trapping is simulated. The results show that when the velocity of the molecular beam is 10 m/s and the loading time is 0.9964 ms, the maximum loading efficiency reaches 94.25% and the temperature of the trapped molecules reaches about 30.3 mK. A single well can be split into two wells, which is of significant importance to the precision measurement and interference of matter waves. This scheme, in addition, can be further miniaturized to construct one-dimensional, two-dimensional, and three-dimensional spatial electrostatic lattices.

Full 3-D stratigraphic inversion with a priori information: a powerful way to optimize data integration

Energy Technology Data Exchange (ETDEWEB)

Grizon, L.; Leger, M.; Dequirez, P.Y.; Dumont, F.; Richard, V.

1998-12-31

Integration between seismic and geological data is crucial to ensure that a reservoir study is accurate and reliable. To reach this goal, there is used a post-stack stratigraphic inversion with a priori information. The global cost-function combines two types of constraints. One is relevant to seismic amplitudes, and the other to an a priori impedance model. This paper presents this flexible and interpretative inversion to determine acoustic impedances constrained by seismic data, log data and geologic information. 5 refs., 8 figs.

Highly charged ion trapping and cooling

International Nuclear Information System (INIS)

Beck, B. R.; Church, D. A.; Gruber, L.; Holder, J. P.; Schneider, D.; Steiger, J.

1998-01-01

In the past few years a cryogenic Penning trap (RETRAP) has been operational at the Electron Beam Ion Trap (EBIT) facility at Lawrence Livermore National Laboratory. The combination of RETRAP and EBIT provides a unique possibility of producing and re-trapping highly charged ions and cooling them to very low temperatures. Due to the high Coulomb potentials in such an ensemble of cold highly charged ions the Coulomb coupling parameter (the ratio of Coulomb potential to the thermal energy) can easily reach values of 172 and more. To study such systems is not only of interest in astrophysics to simulate White Dwarf star interiors but opens up new possibilities in a variety of areas (e.g. laser spectroscopy), cold highly charged ion beams

Neutrophil Extracellular Traps in Ulcerative Colitis

DEFF Research Database (Denmark)

Bjerg Bennike, Tue; Carlsen, Thomas Gelsing; Ellingsen, Torkell

2015-01-01

microscopy and confocal microscopy. RESULTS: We identified and quantified 5711 different proteins with proteomics. The abundance of the proteins calprotectin and lactotransferrin in the tissue correlated with the degree of tissue inflammation as determined by histology. However, fecal calprotectin did...... not correlate. Forty-six proteins were measured with a statistically significant differences in abundances between the UC colon tissue and controls. Eleven of the proteins with increased abundances in the UC biopsies were associated with neutrophils and neutrophil extracellular traps. The findings were...... validated by microscopy, where an increased abundance of neutrophils and the presence of neutrophil extracellular traps by extracellular DNA present in the UC colon tissue were confirmed. CONCLUSIONS: Neutrophils, induced neutrophil extracellular traps, and several proteins that play a part in innate...

A metastable helium trap for atomic collision physics

International Nuclear Information System (INIS)

Colla, M.; Gulley, R.; Uhlmann, L.; Hoogerland, M.D.; Baldwin, K.G.H.; Buckman, S.J.

1999-01-01

Full text: Metastable helium in the 2 3 S state is an important species for atom optics and atomic collision physics. Because of its large internal energy (20eV), long lifetime (∼8000s) and large collision cross section for a range of processes, metastable helium plays an important role in atmospheric physics, plasma discharges and gas laser physics. We have embarked on a program of studies on atom-atom and electron-atom collision processes involving cold metastable helium. We confine metastable helium atoms in a magneto-optic trap (MOT), which is loaded by a transversely collimated, slowed and 2-D focussed atomic beam. We employ diode laser tuned to the 1083 nm (2 3 S 1 - 2 3 P2 1 ) transition to generate laser cooling forces in both the loading beam and the trap. Approximately 10 million helium atoms are trapped at temperatures of ∼ 1mK. We use phase modulation spectroscopy to measure the trapped atomic density. The cold, trapped atoms can collide to produce either atomic He + or molecular He 2 + ions by Penning Ionisation (PI) or Associative Ionisation (AI). The rate of formation of these ions is dependant upon the detuning of the trapping laser from resonance. A further laser can be used to connect the 2 3 S 1 state to another higher lying excited state, and variation of the probe laser detuning used to measure interatomic collision potential. Electron-atom collision processes are studied using a monochromatic electron beam with a well defined spatial current distribution. The total trap loss due to electron collisions is measured as a function of electron energy. Results will be presented for these atomic collision physics measurements involving cold, trapped metastable helium atoms. Copyright (1999) Australian Optical Society

Sognenavne, Odense Kommune (36 artikler). trap.dk

DEFF Research Database (Denmark)

Kællerød, Lars-Jakob Harding

2017-01-01

Artikler til Trap Danmarks netpublikation trap.dk Sognenavnene Agedrup, Allerup, Allese, Ansgars, Bellinge, Bolbro, Brændekilde, Dalum, Davinde, Dyrup, Fangel, Fraugde, Fredens, Hans Tausen, Hjallese, Højby, Korsløkke, Korup, Lumby, Munkebjerg, Næsby, Næsbyhoved-Broby, Paarup, Ravnebjerg, Sanderu...

Geochemistry of Precambrian sedimentary rocks used to solve stratigraphical problems: An example from the Neoproterozoic Volta basin, Ghana

DEFF Research Database (Denmark)

Kalsbeek, F.; Frei, Robert

2010-01-01

The Neoproterozoic Volta basin of Ghana (not, vert, similar115,000 km2; depth up to 5–7 km) consists of flat-lying sedimentary rocks, mainly sandstones that unconformably overlie the crystalline basement of the West-African craton. The stratigraphical column has been subdivided into three main...... and Obosum Groups is used to solve one of the outstanding controversies regarding the stratigraphy of the Volta basin....

Eosinophilic Otitis Media: the Aftermath of Eosinophil Extracellular Trap Cell Death.

Science.gov (United States)

Ueki, Shigeharu; Ohta, Nobuo; Takeda, Masahide; Konno, Yasunori; Hirokawa, Makoto

2017-05-01

Eosinophilic otitis media (EOM) is a refractory disease characterized by the accumulation of eosinophils in middle ear effusion and mucosa. We summarize current knowledge regarding the clinical characteristics and management of EOM. Although eosinophil activation in inflamed foci is involved in the pathogenesis of EOM, little is known about the fate of the eosinophils and aftermath of their cell death. We discuss the possibility that eosinophils undergo non-apoptotic cell death that worsens tissue damage and increases effusion viscosity. Unlike chronic otitis media, EOM is strongly associated with an allergic background. Corticosteroids are currently the only effective pharmacological treatment, and surgical intervention is often required. Mucosal eosinophils infiltrate extensively into the middle ear cavity where they are stimulated by locally produced activators including interleukin-5 and eotaxin. The eosinophils undergo cytolysis in the effusion, which represents a major fate of activated eosinophils in vivo. Recent data revealed cytolysis could be renamed as extracellular trap cell death (ETosis). ETosis represents suicidal cell death involving total cell degranulation and development of sticky chromatin structures (extracellular traps (ETs)). The characteristics of eosinophil- and neutrophil-derived ET polymers might contribute to the difference in viscosity of secretions between EOM and common chronic otitis media. The extracellular products remaining after eosinophil ETosis are an important aspect of EOM pathology. The concept of ETosis also has novel implications for potential therapeutic modalities in various eosinophilic disorders.

Radionuclide trap for liquid metal cooled reactors

International Nuclear Information System (INIS)

McGuire, J.C.; Brehm, W.F.

1978-10-01

At liquid metal cooled reactor operating temperatures, radioactive corrosion product transport and deposition in the primary system will be sufficiently high to limit access time for maintenance of system components. A radionuclide trap has been developed to aid in controlling radioactivity transport. This is a device which is located above the reactor core and which acts as a getter, physically immobilizing radioactive corrosion products, particularly 54 Mn. Nickel is the getter material used. It is most effective at temperatures above 450 0 C and effectiveness increases with increasing temperature. Prototype traps have been tested in sodium loops for 40,000 hours at reactor primary temperatures and sodium velocities. Several possible in-reactor trap sites were considered but a location within the top of each driver assembly was chosen as the most convenient and effective. In this position the trap is changed each time fuel is changed

Can camera traps monitor Komodo dragons a large ectothermic predator?

Science.gov (United States)

Ariefiandy, Achmad; Purwandana, Deni; Seno, Aganto; Ciofi, Claudio; Jessop, Tim S

2013-01-01

Camera trapping has greatly enhanced population monitoring of often cryptic and low abundance apex carnivores. Effectiveness of passive infrared camera trapping, and ultimately population monitoring, relies on temperature mediated differences between the animal and its ambient environment to ensure good camera detection. In ectothermic predators such as large varanid lizards, this criterion is presumed less certain. Here we evaluated the effectiveness of camera trapping to potentially monitor the population status of the Komodo dragon (Varanus komodoensis), an apex predator, using site occupancy approaches. We compared site-specific estimates of site occupancy and detection derived using camera traps and cage traps at 181 trapping locations established across six sites on four islands within Komodo National Park, Eastern Indonesia. Detection and site occupancy at each site were estimated using eight competing models that considered site-specific variation in occupancy (ψ)and varied detection probabilities (p) according to detection method, site and survey number using a single season site occupancy modelling approach. The most parsimonious model [ψ (site), p (site survey); ω = 0.74] suggested that site occupancy estimates differed among sites. Detection probability varied as an interaction between site and survey number. Our results indicate that overall camera traps produced similar estimates of detection and site occupancy to cage traps, irrespective of being paired, or unpaired, with cage traps. Whilst one site showed some evidence detection was affected by trapping method detection was too low to produce an accurate occupancy estimate. Overall, as camera trapping is logistically more feasible it may provide, with further validation, an alternative method for evaluating long-term site occupancy patterns in Komodo dragons, and potentially other large reptiles, aiding conservation of this species.

Commissioning of the double Penning trap system MLLTRAP

Energy Technology Data Exchange (ETDEWEB)

Kolhinen, V.S. [Fakultaet fuer Physik, LMU Muenchen and Maier-Leibnitz Laboratory, Am Coulombwall 1, 85748 Garching (Germany)], E-mail: veli.kolhinen@physik.uni-muenchen.de; Bussmann, M. [Fakultaet fuer Physik, LMU Muenchen and Maier-Leibnitz Laboratory, Am Coulombwall 1, 85748 Garching (Germany); Forschungszentrum Dresden-Rossendorf, 01314 Dresden (Germany); Gartzke, E.; Habs, D.; Neumayr, J.B.; Schuermann, C.; Szerypo, J.; Thirolf, P.G. [Fakultaet fuer Physik, LMU Muenchen and Maier-Leibnitz Laboratory, Am Coulombwall 1, 85748 Garching (Germany)

2009-03-01

A cylindrical double Penning trap system has been installed and commissioned at the Maier-Leibnitz-Laboratory (MLL) in Garching. This trap system has been designed to isobarically purify low-energy ion beams and perform highly accurate mass measurements. Technical details of the device and the first results of the commissioning measurements will be presented. The mass resolving power achieved in the first trap for {sup 85}Rb ions is R=139(2)x10{sup 3}, while a relative mass uncertainty of {delta}m/m=2.9x10{sup -8} was reached with the second trap (no analysis of systematic uncertainties included) when using {sup 87}Rb as a reference ion for {sup 85}Rb.

Diffusion and trapping of positive muons in niobium

International Nuclear Information System (INIS)

Boekema, C.; Heffner, R.H.; Hutson, R.L.; Leon, M.; Schillaci, M.E.; Kossler, W.J.; Numan, M.; Dodds, S.A.

1982-01-01

Using zero- and longitudinal-field muon spin relaxation, the conventional interpretation of the ''double-humped'' behavior of the μ + -depolarization rate in Nb has been established unambiguously. Thus the μ + mobility is shown to increase monotonically with temperature. The widths of the magnetic field distributions (due to the Nb nuclear moments) and the rates for finding or escaping from traps have been measured at several temperatures. In addition, equations are presented which govern the time evolution of the μ + polarization, when the muons are finding traps, escaping from traps, or both, for zero, longitudinal, and transverse external magnetic fields. A method for including the effect of more than one kind of trap acting at a particular temperature is given

Diffusion and trapping of positive muons in niobium

International Nuclear Information System (INIS)

Boekema, C.; Heffner, R.H.; Hutson, R.L.; Leon, M.; Schillaci, M.E.; Kossler, W.J.; Numan, M.; Dodds, S.A.

1982-01-01

Using zero- and longitudinal-field μSR, the conventional interpretation of the double-humped behavior of the μ + -depolarization rate in Nb has been established unambiguously. Thus the μ + mobility is shown to increase monotonically with temperature. The widths of the magnetic field distributions (due to the Nb nuclear moments) and the rates for finding or escaping from traps have been measured at several temperatures. In addition, equations are presented which govern the time-evolution of the μ + polarization, when the muons are finding traps, escaping from traps, or both, for zero, longitudinal, and transverse external magnetic fields. A method for including the effect of more than one kind of trap acting at a particular temperature is given

3D-Printed external light traps for solar cells

NARCIS (Netherlands)

van Dijk, L.; Paetzold, U.W.; Blab, Gerhard; Marcus, E.A.P.; Oostra, A.J.; van de Groep, J.; Polman, A.; Schropp, R.E.I.; Di Vece, M.

2015-01-01

We demonstrate a universally applicable 3D-printed external light trap for solar cells. We placed a macroscopic external light trap made of smoothened, silver coated plastic at the sun-facing surface of different types of solar cells. The trap consists of a reflective parabolic concentrator on top

Using malaise traps to sample ground beetles (Coleoptera: Carabidae).

Energy Technology Data Exchange (ETDEWEB)

Ulyshen, Michael D., James L. Hanula, and Scott Horn

2005-01-01

Pitfall traps provide an easy and inexpensive way to sample ground-dwelling arthropods (Spence and Niemela 1994; Spence et al. 1997; Abildsnes and Tommeras 2000) and have been used exclusively in many studies of the abundance and diversity of ground beetles (Coleoptera: Carabidae). Despite the popularity of this trapping technique, pitfall traps have many disadvantages. For example, they often fail to collect both small (Spence and Niemela 1994) and trap-shy species (Benest 1989), eventually deplete the local carabid population (Digweed et al. 1995), require a species to be ground-dwelling in order to be captured (Liebherr and Mahar 1979), and produce different results depending on trap diameter and material, type of preservative used, and trap placement (Greenslade 1964; Luff 1975; Work et al. 2002). Further complications arise from seasonal patterns of movement among the beetles themselves (Maelfait and Desender 1990), as well as numerous climatic factors, differences in plant cover, and variable surface conditions (Adis 1979). Because of these limitations, pitfall trap data give an incomplete picture of the carabid community and should be interpreted carefully. Additional methods, such as use of Berlese funnels and litter washing (Spence and Niemela 1994), collection from lights (Usis and MacLean 1998), and deployment of flight intercept devices (Liebherr and Mahar 1979; Paarmann and Stork 1987), should be incorporated in surveys to better ascertain the species composition and relative numbers of ground beetles. Flight intercept devices, like pitfall traps, have the advantage of being easy to use and replicate, but their value to carabid surveys is largely unknown. Here we demonstrate the effectiveness of Malaise traps for sampling ground beetles in a bottomland hardwood forest.

Using malaise traps to sample ground beetles (Coleoptera. Carabidae)

Energy Technology Data Exchange (ETDEWEB)

Ulyshen, Michael D. [USDA Forest Service, Savannah River, New Ellenton, SC (United States); Hanula, James L. [USDA Forest Service, Savannah River, New Ellenton, SC (United States); Horn, Scott [USDA Forest Service, Savannah River, New Ellenton, SC (United States)

2012-04-02

Pitfall traps provide an easy and inexpensive way to sample ground-dwelling arthropods (Spence and Niemela 1994; Spence et al. 1997; Abildsnes and Tommeras 2000) and have been used exclusively in many studies of the abundance and diversity of ground beetles (Coleoptera: Carabidae). Despite the popularity of this trapping technique, pitfall traps have many disadvantages. For example, they often fail to collect both small (Spence and Niemela 1994) and trap-shy species (Benest 1989), eventually deplete the local carabid population (Digweed et al. 1995), require a species to be ground-dwelling in order to be captured (Liebherr and Mahar 1979), and produce different results depending on trap diameter and material, type of preservative used, and trap placement (Greenslade 1964; Luff 1975; Work et al. 2002). Further complications arise from seasonal patterns of movement among the beetles themselves (Maelfait and Desender 1990), as well as numerous climatic factors, differences in plant cover, and variable surface conditions (Adis 1979). Because of these limitations, pitfall trap data give an incomplete picture of the carabid community and should be interpreted carefully. Additional methods, such as use of Berlese funnels and litter washing (Spence and Niemela 1994), collection from lights (Usis and MacLean 1998), and deployment of flight intercept devices (Liebherr and Mahar 1979; Paarmann and Stork 1987), should be incorporated in surveys to better ascertain the species composition and relative numbers of ground beetles. Flight intercept devices, like pitfall traps, have the advantage of being easy to use and replicate, but their value to carabid surveys is largely unknown. Here we demonstrate the effectiveness of Malaise traps for sampling ground beetles in a bottomland hardwood forest.

Optical macro-tweezers: trapping of highly motile micro-organisms

International Nuclear Information System (INIS)

Thalhammer, G; Steiger, R; Bernet, S; Ritsch-Marte, M

2011-01-01

Optical micromanipulation stands for contact-free handling of microscopic particles by light. Optical forces can manipulate non-absorbing objects in a large range of sizes, e.g., from biological cells down to cold atoms. Recently much progress has been made going from the micro- down to the nanoscale. Less attention has been paid to going the other way, trapping increasingly large particles. Optical tweezers typically employ a single laser beam tightly focused by a microscope objective of high numerical aperture to stably trap a particle in three dimensions (3D). As the particle size increases, stable 3D trapping in a single-beam trap requires scaling up the optical power, which eventually induces adverse biological effects. Moreover, the restricted field of view of standard optical tweezers, dictated by the use of high NA objectives, is particularly unfavorable for catching actively moving specimens. Both problems can be overcome by traps with counter-propagating beams. Our 'macro-tweezers' are especially designed to trap highly motile organisms, as they enable three-dimensional all-optical trapping and guiding in a volume of 2 × 1 × 2 mm 3 . Here we report for the first time the optical trapping of large actively swimming organisms, such as for instance Euglena protists and dinoflagellates of up to 70 µm length. Adverse bio-effects are kept low since trapping occurs outside high intensity regions, e.g., focal spots. We expect our approach to open various possibilities in the contact-free handling of 50–100 µm sized objects that could hitherto not be envisaged, for instance all-optical holding of individual micro-organisms for taxonomic identification, selective collecting or tagging

Trapping of deuterium in argon-implanted nickel

International Nuclear Information System (INIS)

Frank, R.C.; Rehn, L.E.; Baldo, P.

1985-01-01

Argon ions with energy 250 keV were implanted at fluences of 2 x 10 16 cm -2 at temperatures of 500, 250, and 21 0 C, in the specimen of relatively pure polycrystalline nickel. Deuterium was introduced into the surface and implanted regions by making the specimen the negative electrode of an electrolytic cell containing 1-N pure deuterated sulfuric acid. Deuterium trapped in the vacancy complexes of the implanted regions was analyzed as a function of temperature using the vacancy complexes of the implanted regions was analyzed as a function of temperature using the 2 H( 3 He, 1 H) 4 He nuclear reaction during an isochronal annealing process. The results indicate that the types of traps and trap densities found in the regions implanted at 21 and 250 0 C were essentially identical while the trap density found in the region implanted at 500 0 C was approximately 40% of that found in the other regions. Math model comparison with the experimental results suggests the existence of at least two types of traps in each region. Trap binding enthalpies used in the math model to fit the experimental data were slightly higher for the region implanted with argon at 500 0 C than for the regions implanted at the lower temperatures. TEM studies revealed the presence of small voids in the region implanted at 500 0 as well as dislocation loops similar to those found in the regions implanted at the lower temperatures. 20 references, 2 figures

Quasi-Linear Evolution of Trapped Electron Fluxes Under the Influence of Realistic Whistler-Mode Waves

Science.gov (United States)

Agapitov, O. V.; Mourenas, D.; Artemyev, A.; Krasnoselskikh, V.

2014-12-01

The evolution of fluxes of energetic trapped electrons as a function of geomagnetic activity is investigated using brand new statistical models of chorus waves derived from Cluster observations in the radiation belts. The new wave models provide the distributions of wave power and wave-normal angle with latitude as a function of either Dst or Kp indices. Lifetimes and energization of energetic electrons are examined, as well as the relevant uncertainties related to some of the wave models implicit assumptions.From the presented results, different implications concerning the characterization of relativistic flux enhancements and losses are provided.

Revisiting the `forbidden' region: AGN radiative feedback with radiation trapping

Science.gov (United States)

Ishibashi, W.; Fabian, A. C.; Ricci, C.; Celotti, A.

2018-06-01

Active galactic nucleus (AGN) feedback, driven by radiation pressure on dust, is an important mechanism for efficiently coupling the accreting black hole to the surrounding environment. Recent observations confirm that X-ray selected AGN samples respect the effective Eddington limit for dusty gas in the plane defined by the observed column density versus the Eddington ratio, the so-called NH - λ plane. A `forbidden' region occurs in this plane, where obscuring clouds cannot be long-lived, due to the action of radiation pressure on dust. Here we compute the effective Eddington limit by explicitly taking into account the trapping of reprocessed radiation (which has been neglected in previous works), and investigate its impact on the NH - λ plane. We show that the inclusion of radiation trapping leads to an enhanced forbidden region, such that even Compton-thick material can potentially be disrupted by sub-Eddington luminosities. We compare our model results to the most complete sample of local AGNs with measured X-ray properties, and find good agreement. Considering the anisotropic emission from the accretion disc, we also expect the development of dusty outflows along the polar axis, which may naturally account for the polar dust emission recently detected in several AGNs from mid-infrared observations. Radiative feedback thus appears to be the key mechanism regulating the obscuration properties of AGNs, and we discuss its physical implications in the context of co-evolution scenarios.

Charge trapping/de-trapping in nitrided SiO2 dielectrics and its influence on device reliability

Science.gov (United States)

Kambour, Kenneth; Hjalmarson, Harold; Nguyen, Duc; Kouhestani, Camron; Devine, Roderick

2012-02-01

Field effect devices with insulator gate dielectrics are excellent test vehicles to probe the physics of defects and charge trapping in the insulator/ semiconductor structure. p-channel field effect device reliability under negative bias stressing has been identified to originate from at least two terms: a) charged defect generation at the Si substrate/SiOxNy interface and b) charge trapping at neutral defect pre-cursors in the ``bulk'' of the SiOxNy beyond the interface. Measurements of transistor characteristics enable extraction of the two terms. We report the results of such measurements and demonstrate that short time effects are associated primarily with electric field assisted tunneling of holes from the inversion layer to neutral traps. This is confirmed by bias stressing measurements at different frequencies in the range 1 Hz to 2 MHz. First principles modeling of the tunneling/trapping phenomena is presented. K.Kambour worked under contract FA9453-08-C-0245 with the Air Force Research Laboratory/RVSE. Sandia National Labs is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

Stratigraphical sequence and geochronology of the volcanic rock series in caifang basin, south jiangxi

International Nuclear Information System (INIS)

Xu Xunsheng; Wu Jianhua

2010-01-01

The late Mesozoic volcanic rocks in Jiangxi constitute two volcanic belts: the northern is Xiajiang-Guangfeng volcanic belt, the volcanic rocks series belong to one volcano cycle and named Wuyi group which is subdivided into three formations (Shuangfengling formation, Ehuling formation and Shixi formation); the southern is Sannan-Xunwu volcanic belt, the volcanic rocks series in Caifang basin which locates on Sannan-Xunwu volcanic belt also belong to only one volcano cycle. It can be subdivided into two lithology and lithofacies units (upper and lower): the lower unit consists of sedimentary rocks and associated with a subordinate amount of volcanic rocks, it belongs to erupt-deposit facies which is the product of early volcanic stage; the upper unit is mostly composed of volcanic rocks, it belongs to erupt facies that is the volcanic eruption product. SHRIMP zircon U-Pb age of rhyolite? which locates at the top of the upper unit is 130.79 ± 0.73) Ma. According to the new International Stratigraphic Chart, the boundary of Jurassic and Cretaceous is (145.4 ± 4.0) Ma, so the age shows that the geologic period of Caifang volcanic rocks series is early Early Cretaceous epoch. On the basis of lithological correlation, lithofacies and stratigraphic horizon analysis, the volcanic rock series in Caifang basin fall under Wuyi group, and the lower unit could be incorporated into Shuangfengling formation, the upper unit could be incorporated into Ehuling formation. The subdivision of sequence and the determination of geochronology of the volcanic rock series in Caifang basin provide some references for the study of the late Mesozoic volcanic rocks series of the Sannan-Xunwu volcanic belt. (authors)

Ultratrace determination of lead by hydride generation in-atomizer trapping atomic absorption spectrometry: Optimization of plumbane generation and analyte preconcentration in a quartz trap-and-atomizer device

Energy Technology Data Exchange (ETDEWEB)

Kratzer, Jan, E-mail: jkratzer@biomed.cas.cz

2012-05-15

A compact trap-and-atomizer device and a preconcentration procedure based on hydride trapping in excess of oxygen over hydrogen in the collection step, both constructed and developed previously in our laboratory, were employed to optimize plumbane trapping in this device and to develop a routine method for ultratrace lead determination subsequently. The inherent advantage of this preconcentration approach is that 100% preconcentration efficiency for lead is reached in this device which has never been reported before using quartz or metal traps. Plumbane is completely retained in the trap-and-atomizer device at 290 Degree-Sign C in oxygen-rich atmosphere and trapped species are subsequently volatilized at 830 Degree-Sign C in hydrogen-rich atmosphere. Effect of relevant experimental parameters on plumbane trapping and lead volatilization are discussed, and possible trapping mechanisms are hypothesized. Plumbane trapping in the trap-and-atomizer device can be routinely used for lead determination at ultratrace levels reaching a detection limit of 0.21 ng ml{sup -1} Pb (30 s preconcentration, sample volume 2 ml). Further improvement of the detection limit is feasible by reducing the blank signal and increasing the trapping time. - Highlights: Black-Right-Pointing-Pointer In-atomizer trapping HG-AAS was optimized for Pb. Black-Right-Pointing-Pointer A compact quartz trap-and-atomizer device was employed. Black-Right-Pointing-Pointer Generation, preconcentration and atomization steps were investigated in detail. Black-Right-Pointing-Pointer 100% preconcentration efficiency for lead was reached. Black-Right-Pointing-Pointer Routine analytical method was developed for Pb determination (LOD of 0.2 ng ml{sup -1} Pb).