Sulphur highways : value-added solutions to create sulphur demand

Energy Technology Data Exchange (ETDEWEB)

Macedo, R.

2010-09-15

Producers generally view sulphur as a nuisance with essentially no benefit. In Alberta, a greater portion of sulphur production will shift from natural gas to the oilsands producing areas where there is limited infrastructure to move it out. Increased amounts of sour oil and gas production together with greater fuel desulphurization have also led to more sulphur being produced. In order to address the inevitable storage issue, Shell is considering value-added uses for the product, such as sulphur asphalt. The company developed Thiopave, a sulphur-based product for use in asphalt paving mixtures that can improve the mechanical performance of asphalt. The sulphur can be added to the asphalt mix as a solid pellet, which helps reduce the emission of sulphur vapour, odour and eye irritation. Twenty Thiopave projects are planned for the 2010 paving season in 9 U.S. states and 2 Canadian provinces. Sulphur Enhanced Asphalt Modifier (SEAM) was the first generation of Thiopave developed in 2003. SEAM replaces 20 to 25 percent by volume of the bitumen in asphalt mix. The properties allow Thiopave-enhanced roads to perform better than conventional roads in both consistently high temperature regions and climates with wide temperature variations. In 2007, an asphalt mix containing 40 percent by mass of Thiopave was used in a trial in Qatar. The Thiopave asphalt mix was compared with a conventional mix at temperatures ranging from 10 to 40 degrees C to determine the stiffness ratio. It was determined that Thiopave mixes containing high-penetration bitumen can be used to build temperature resistant roads that are stiffer in hot summer temperatures while improving the pavement's cold weather cracking performance. 1 ref., 4 figs.

Forest fuel and sulphur

International Nuclear Information System (INIS)

Lundborg, A.

1994-10-01

This report illustrates the sulphur cycle in forest fuel and in the forest ecosystem. The hypothesis is that sulphur dioxide from combustion of forest fuel is not more acidifying than sulphur that is mineralized from tree biomass if it is left in the forest instead of being burnt. The report gives an overview of the sulphur cycle in general together with the acidifying effect of sulphur. The sulphur content in wood biomass is about 1 mg/g in the needles and 0.2-0.3 mg/g in wood. Chipped forest fuel contains 0.2-0.5 mg S/g. A removal of 40 tonnes of felling residues per hectare may contain about 8-30 kg S. The sulphur occurs both in organic, often reduced, form and as sulphate. In situations of high availability to sulphur there will be an increased proportion of sulphate. After combustion some, perhaps half, of the sulphur is left in the ashes, most of which appears to be sulphate. In mineralisation of reduced organic sulphur, of type R-SH, the sulphur is released in the form of sulphide. Hydrogen sulphide, H2S, can be oxidised by microbes to sulphate, which should be acidifying (2 H+ will remain). A very rough estimate suggests that emissions of sulphur dioxide from forest fuel, spread over the period the trees are growing, and on the area from which the trees are taken, corresponds to 0.5% of the sulphur deposition in southern Sweden. Sulphur emissions from biofuel combustion are much lower than Sweden's and the EU's most stringent emission limits for coal. Whole-tree removal with return of ashes will theoretically give a considerable reduction in soil acidity since large quantities of nitrogen are removed and thus the acidifying effect of nitrogen will not occur. This should be of greater importance for forest acidification than the effect of biomass sulphur. 80 refs, numerous tabs

Sulphur cement pre-composition and process for preparing such sulphur cement pre-composition

NARCIS (Netherlands)

2013-01-01

The invention provides a process for the preparation of a sulphur cement pre-composition comprising reacting sulphur modifier with polysulphide-containing organosilane to obtain in the presence of sulphur the sulphur cement pre-composition, wherein the organosilane has the general molecular formula:

LavaSIM: the effect of heat transfer in 3D on lava flow characteristics (Invited)

Science.gov (United States)

Fujita, E.

2013-12-01

Characteristics of lava flow are governed by many parameters like lava viscosity, effusion rate, ground topography, etc. The accuracy and applicability of lava flow simulation code is evaluated whether the numerical simulation can reproduce these features quantitatively, which is important from both strategic and scientific points of views. Many lava flow simulation codes are so far proposed, and they are classified into two categories, i.e., the deterministic and the probabilistic models. LavaSIM is one of the former category models, and has a disadvantage of time consuming. But LavaSIM can solves the equations of continuity, motion, energy by step and has an advantage in the calculation of three-dimensional analysis with solid-liquid two phase flow, including the heat transfer between lava, solidified crust, air, water and ground, and three-dimensional convection in liquid lava. In other word, we can check the detailed structure of lava flow by LavaSIM. Therefore, this code can produce both channeled and fan-dispersive flows. The margin of the flow is solidified by cooling and these solidified crusts control the behavior of successive lava flow. In case of a channel flow, the solidified margin supports the stable central main flow and elongates the lava flow distance. The cross section of lava flow shows that the liquid lava flows between solidified crusts. As for the lava extrusion flow rate, LavaSIM can include the time function as well as the location of the vents. In some cases, some parts of the solidified wall may be broken by the pressure of successive flow and/or re-melting. These mechanisms could characterize complex features of the observed lava flows at many volcanoes in the world. To apply LavaSIM to the benchmark tests organized by V-hub is important to improve the lava flow evaluation technique.

Introducing Kansas Lava

Science.gov (United States)

Gill, Andy; Bull, Tristan; Kimmell, Garrin; Perrins, Erik; Komp, Ed; Werling, Brett

Kansas Lava is a domain specific language for hardware description. Though there have been a number of previous implementations of Lava, we have found the design space rich, with unexplored choices. We use a direct (Chalmers style) specification of circuits, and make significant use of Haskell overloading of standard classes, leading to concise circuit descriptions. Kansas Lava supports both simulation (inside GHCi), and execution via VHDL, by having a dual shallow and deep embedding inside our Signal type. We also have a lightweight sized-type mechanism, allowing for MATLAB style matrix based specifications to be directly expressed in Kansas Lava.

Mantle to surface degassing of carbon- and sulphur-rich alkaline magma at El Hierro, Canary Islands

Science.gov (United States)

Longpré, Marc-Antoine; Stix, John; Klügel, Andreas; Shimizu, Nobumichi

2017-02-01

Basaltic volcanoes transfer volatiles from the mantle to the surface of the Earth. The quantification of deep volatile fluxes relies heavily on estimates of the volatile content of primitive magmas, the best archive of which is provided by melt inclusions. Available data from volcanoes producing mafic alkaline lavas in a range of tectonic settings suggest high volatile fluxes, but information remains sparse, particularly for intraplate ocean islands. Here we present measurements of volatile and trace element concentrations, as well as sulphur speciation, in olivine-hosted melt inclusions and matrix glasses from quenched basanite lava balloon samples from the 2011-2012 submarine eruption at El Hierro, Canary Islands. The results reveal remarkably high concentrations of dissolved volatiles and incompatible trace elements in this magma, with ∼80 ppm Nb and up to 3420 ppm CO2, 3.0 wt.% H2O and 5080 ppm S. Reconstructed primitive CO2 contents, considering CO2/Nb systematics and possible CO2 sequestration in shrinkage bubbles, reach weight percent levels, indicating that carbon is a major constituent of Canary Island magmas at depth and that exsolution of a CO2-rich fluid begins in the mantle at pressures in excess of 1 GPa. Correlations between sulphur concentration, sulphur speciation and water content suggest strong reduction of an initially oxidised mantle magma, likely controlled by coupled H2O and S degassing. This late-stage redox change may have triggered sulphide saturation, recorded by globular sulphide inclusions in clinopyroxene and ulvöspinel. The El Hierro basanite thus had a particularly high volatile-carrying capacity and released a minimum of 1.3-2.1 Tg CO2 and 1.8-2.9 Tg S to the environment, causing substantial stress on the local submarine ecosystem. These results highlight the important contribution of alkaline ocean island volcanoes, such as the Canary Islands, to volatile fluxes from the mantle.

Sulphur recovery and sulphur emissions at Alberta sour gas plants : annual report for 2005

International Nuclear Information System (INIS)

2005-01-01

The sulphur recovery of Alberta's grandfathered sour gas plants is monitored by the Alberta Energy and Utilities Board. This report provides an annual summary of industry performance for sulphur recovery at large acid gas flaring sour gas plants, and sulphur recovery at all acid gas injection sour gas plants. It follows Interim Directive (ID) 2001-3 which stipulates guidelines for sulphur recovery for the province of Alberta. It includes a list of grandfathered and non grandfathered plants in Alberta. Grandfathered sulphur recovery plants that exceed expectations have the option to file a sulphur emission performance credit report and can use the credits to meet some of their sulphur requirement in the future. Acid gas flaring plants face more stringent requirements and cannot earn credits. Several plants have degrandfathered in the past 5 years. Eleven have made upgrades, 4 have been relicensed to meet the requirements for new plants, and 4 have shut down. Forty-one grandfathered plants remain. Sulphur emissions have decreased 39 per cent for grandfathered acid gas flaring plants, and 28 per cent for grandfathered sulphur recovery plants. 10 tabs., 3 figs

Sumpor u ugljenu (Sulphur in Coal

Directory of Open Access Journals (Sweden)

Rađenović, A.

2004-12-01

Full Text Available The presence of sulphur in coal possesses important environmetal problems in its usage. The sulphur dioxide (S02 emissions produced during coal combustion account for a significant proportion of the total global output of anthropogenic SO2. The extent of sulphur separation depends on several variables such as the form of sulphur in coal, intimacy of contact between minerals and the products of devolatilization. The total sulphur in coal varies in the range of 0.2 - 11 wt %, although in most cases it is beetwen 1 and 3 wt %. Sulphur occurs in a variety of both inorganic and organic forms. Inorganic sulphur is found mainly as iron pyrite, marcasite, pyrrhotite, sphalerite, galena, chalcopirite and as sulphates (rarely exceeds w = 0,1 %. Organic sulphur is found in aromatic rings and aliphatic functionalities usually as mercaptans, aliphatic and aryl sulfides, disulfides and thiophenes. Organic and pyritic sulphur quantities depend on coal rank. Higher rank coals tend to have a high proportion of labile sulphur. All the organic sulphur is bivalent and it is spread throughout the organic coal matrix. Sulphur occurs in all the macerals and most minerals. Vitrinite contains the major part of organic sulphur and metals. Elemental sulphur is produced during coal weathering. The depolymerization methods as pyrolysis and hydrogenation are very drastic methods wich change the structure of the coal and the sulphur groups. In the case of pyrolysis, high levels of desulphurization, in chars and additional production of liquid hydrocarbon can be achieved. Thiophenes and sulphides were the major sulphur components of tars from coal pyrolysis. Hyrdogen sulphide and the lower mercaptans and sulphides were found in the volatile matters. Hydrogen sulphide and thiophenes are practically the only sulphur products of coal hydrogenation. H2S is produced in char hydrodesulphurization. A number of options are available for reducing sulphur emissions including the

Sulphurous mineral waters

Directory of Open Access Journals (Sweden)

Iluta Alexandru

2011-09-01

Full Text Available Sulphurous waters contain at least 1mg H2S, HS, S or thiosulphate per liter or complex colloidal sulfur water is presented as of simple or mixed sulphide (alkali, carbonated, chlorinated sodium.In the sulphurous waters, sulfur is found in several forms (hydrogen sulfide, free sulfide, sulfide groups, polysulfides acids. Yellow, opalescent white precipitate and deposit a glass of water on the bottom of sulphur oxidation by indicates the intensity of the wateroxidation process by oxygen in the air.

Lunar Lava Tube Sensing

Science.gov (United States)

York, Cheryl Lynn; Walden, Bryce; Billings, Thomas L.; Reeder, P. Douglas

1992-01-01

Large (greater than 300 m diameter) lava tube caverns appear to exist on the Moon and could provide substantial safety and cost benefits for lunar bases. Over 40 m of basalt and regolith constitute the lava tube roof and would protect both construction and operations. Constant temperatures of -20 C reduce thermal stress on structures and machines. Base designs need not incorporate heavy shielding, so lightweight materials can be used and construction can be expedited. Identification and characterization of lava tube caverns can be incorporated into current precursor lunar mission plans. Some searches can even be done from Earth. Specific recommendations for lunar lava tube search and exploration are (1) an Earth-based radar interferometer, (2) an Earth-penetrating radar (EPR) orbiter, (3) kinetic penetrators for lunar lava tube confirmation, (4) a 'Moon Bat' hovering rocket vehicle, and (5) the use of other proposed landers and orbiters to help find lunar lava tubes.

Quantifying Sulphur Emissions and Atmospheric Aerosol Loading From the 1730-36 Lanzarote Eruption

Science.gov (United States)

Sharma, K.; Blake, S.; Self, S.

2005-12-01

The AD 1730-36 eruption of Lanzarote (Canary Islands) is the third largest basaltic fissure eruption known to have occurred in the last 1000 years, after the Icelandic events of Laki (AD 1783-84) and Eldgja (AD 934). Our new volume estimates suggest that the Lanzarote eruption produced ~6 km3 of alkali basalt magma along a 15-km long, E-W trending fissure. Eruptive activity occurred in five distinct phases. Each phase began with Strombolian fire fountain activity, building large spatter and scoria cones. This was accompanied and followed by effusive aa and pahoehoe lava flow emplacement. As studies in Iceland have shown, this type of sustained fissure eruption can release large amounts of SO2 to the upper atmosphere, leading to the formation of sulphate aerosol clouds and causing widespread environmental damage and human suffering. Matrix glasses in scoria and surface lava samples have 80-300 ppm S (EMPA) and 300-600 ppm H2O (FTIR), whereas glass inclusions in olivine have 420-2650 ppm S and 1000-5000 ppm H2O. Low sulphur inclusions are believed to be partially degassed, representing melt that was trapped during degassing-induced crystallization that occurred as a result of shallow decompression. The inclusions with the highest sulphur contents trap the original un-degassed melt, as indicated by their consistent S/K2O ratio (0.22). The high sulphur contents are also consistent with our finding, from olivine-spinel equilibria, that the magma was relatively oxidized (log fO2 -4.8) therefore favouring the formation of sulphate species and preventing sulphide saturation. Our glass analyses indicate that 40 Mt of SO2 was injected into the upper troposphere - lower stratosphere via 12-16-km-high eruption plumes and that over half this amount was released during the first year of activity. This figure correlates with published Greenland ice-core (GISP-2) data that shows an acidity spike in 1731, suggesting stratospheric transport of sulphate aerosol to the North during

Strange and non-strange baryon and antibaryon production in sulphur-tungsten and sulphur-sulphur interactions at 200 A Gev/c

Energy Technology Data Exchange (ETDEWEB)

Holme, A.K.

1995-11-01

The author has studied production of strange and multistrange baryons and antibaryons in central sulphur-tungsten, sulphur-sulphur, and lead-lead interactions at relativistic energies. The spectra of strange baryons and antibaryons provide information about the dynamics of hadronic matter under the extreme conditions realised in these collisions. The particle ratios allow the degree and the nature of the flavour equilibrium to be studied, while the transverse mass distributions provide independent information of the temperatures achieved. 143 refs.

Strange and non-strange baryon and antibaryon production in sulphur-tungsten and sulphur-sulphur interactions at 200 A Gev/c

International Nuclear Information System (INIS)

Holme, A.K.

1995-11-01

The author has studied production of strange and multistrange baryons and antibaryons in central sulphur-tungsten, sulphur-sulphur, and lead-lead interactions at relativistic energies. The spectra of strange baryons and antibaryons provide information about the dynamics of hadronic matter under the extreme conditions realised in these collisions. The particle ratios allow the degree and the nature of the flavour equilibrium to be studied, while the transverse mass distributions provide independent information of the temperatures achieved. 143 refs

The Payun-Matru lava field: a source of analogues for Martian long lava flows

Science.gov (United States)

Giacomini, L.; Pasquarè, G.; Massironi, M.; Frigeri, A.; Bistacchi, A.; Frederico, C.

2007-08-01

The Payun Matru Volcanic complex is a Quaternary fissural structure belonging to the back-arc extensional area of the Andes in the Mendoza Province (Argentina). The eastern portion of the volcanic structure is covered by a basaltic field of pahoehoe lava flows advanced over more than 180 km from the fissural feeding vents that are aligned with a E-W fault system (Carbonilla fault). Thanks to their widespread extension, these flows represent some of the largest lava flows in the world and the Pampas Onduladas flow can be considered the longest sub-aerial individual lava flow on the Earth surface [1,2]. These gigantic flows propagated over the nearly flat surface of the Pampean foreland, moving on a 0.3 degree slope. The very low viscosity of the olivine basalt lavas, coupled with the inflation process and an extensive system of lava tubes are the most probable explanation for their considerable length. The inflation process likely develop under a steady flow rate sustained for a long time [3]. A thin viscoelastic crust, built up at an early stage, is later inflated by the underlying fluid core, which remains hot and fluid thanks to the thermal-shield effect of the crust. The crust is progressively thickened by accretion from below and spreading is due to the continuous creation of new inflated lobes, which develop at the front of the flow. Certain morphological features are considered to be "fingerprints" of inflation [4, 5, 6]; these include tumuli, lava rises, lava lobes and ridges. All these morphologies are present in the more widespread Payun Matru lava flows that, where they form extensive sheetflows, can reach a maximum thickness of more than 20 meters. After the emplacement of the major flows, a second eruptive cycle involved the Payun Matru volcanic structure. During this stage thick and channelized flows of andesitic and dacitic lavas, accompanied the formation of two trachitic and trachiandesitic strato-volcanoes (Payun Matru and Payun Liso) culminated

Use of stable sulphur isotopes to monitor directly the behaviour of sulphur in coal during thermal desulphurization

Science.gov (United States)

Liu, Chao-Li; Hackley, Keith C.; Coleman, D.D.

1987-01-01

A method has been developed using stable sulphur isotope analyses to monitor the behaviour of sulphur forms in a coal during thermal desulphurization. In this method, the natural stable isotopic composition of the pyritic and organic sulphur in coal is used as a tracer to follow their mobility during the desulphurization process. This tracer method is based on the fact that the isotopic compositions of pyritic and organic sulphur are significantly different in some coals. Isotopic results of pyrolysis experiments at temperatures ranging from 350 to 750 ??C indicate that the sulphur released with the volatiles is predominantly organic sulphur. The pyritic sulphur is evolved in significant quantities only when pyrolysis temperatures exceed 500 ??C. The presence of pyrite seems to have no effect on the amount of organic sulphur evolved during pyrolysis. The chemical and isotopic mass balances achieved from three different samples of the Herrin (No. 6) coal of the Illinois Basin demonstrate that this stable isotope tracer method is quantitative. The main disadvantage of this tracing technique is that not all coals contain isotopically distinct organic and pyritic sulphur. ?? 1987.

Temporal Chemical Data for Sediment, Water, and Biological Samples from the Lava Cap Mine Superfund Site, Nevada County, California-2006-2008

Science.gov (United States)

Foster, Andrea L.; Ona-Nguema, Georges; Tufano, Kate; White, Richard III

2010-01-01

The Lava Cap Mine is located about 6 km east of the city of Grass Valley, Nevada County, California, at an elevation of about 900 m. Gold was hosted in quartz-carbonate veins typical of the Sierran Gold Belt, but the gold grain size was smaller and the abundance of sulfide minerals higher than in typical deposits. The vein system was discovered in 1860, but production was sporadic until the 1930s when two smaller operations on the site were consolidated, a flotation mill was built, and a 100-foot deep adit was driven to facilitate drainage and removal of water from the mine workings, which extended to 366 m. Peak production at the Lava Cap occurred between 1934 and 1943, when about 90,000 tons of ore per year were processed. To facilitate removal of the gold and accessory sulfide minerals, the ore was crushed to a very fine sand or silt grain size for processing. Mining operations at Lava Cap ceased in June 1943 due to War Production Board Order L-208 and did not resume after the end of World War II. Two tailings retention structures were built at the Lava Cap Mine. The first was a log dam located about 0.4 km below the flotation mill on Little Clipper Creek, and the second, built in 1938, was a larger earth fill and rip-rap structure constructed about 2 km downstream, which formed the water body now called Lost Lake. The log dam failed during a storm that began on December 31, 1996, and continued into January 1997; an estimated 8,000-10,000 m3 of tailings were released into Little Clipper Creek during this event. Most of the fine tailings were deposited in Lost Lake, dramatically increasing its turbidity and resulting in a temporary 1-1.5 m rise in lake level due to debris blocking the dam spillway. When the blockage was cleared, the lake level quickly lowered, leaving a ?bathtub ring? of very fine tailings deposited substantially above the water line. The U.S. Environmental Protection Agency (EPA) initiated emergency action in late 1997 at the mine site to reduce

Lava tube shatter rings and their correlation with lava flux increases at Kīlauea Volcano, Hawai‘i

Science.gov (United States)

Orr, T.R.

2011-01-01

Shatter rings are circular to elliptical volcanic features, typically tens of meters in diameter, which form over active lava tubes. They are typified by an upraised rim of blocky rubble and a central depression. Prior to this study, shatter rings had not been observed forming, and, thus, were interpreted in many ways. This paper describes the process of formation for shatter rings observed at Kīlauea Volcano during November 2005–July 2006. During this period, tilt data, time-lapse images, and field observations showed that episodic tilt changes at the nearby Pu‘u ‘Ō‘ō cone, the shallow magmatic source reservoir, were directly related to fluctuations in the level of lava in the active lava tube, with periods of deflation at Pu‘u ‘Ō‘ō correlating with increases in the level of the lava stream surface. Increases in lava level are interpreted as increases in lava flux, and were coincident with lava breakouts from shatter rings constructed over the lava tube. The repetitive behavior of the lava flux changes, inferred from the nearly continuous tilt oscillations, suggests that shatter rings form from the repeated rise and fall of a portion of a lava tube roof. The locations of shatter rings along the active lava tube suggest that they form where there is an abrupt decrease in flow velocity through the tube, e.g., large increase in tube width, abrupt decrease in tube slope, and (or) sudden change in tube direction. To conserve volume, this necessitates an abrupt increase in lava stream depth and causes over-pressurization of the tube. More than a hundred shatter rings have been identified on volcanoes on Hawai‘i and Maui, and dozens have been reported from basaltic lava fields in Iceland, Australia, Italy, Samoa, and the mainland United States. A quick study of other basaltic lava fields worldwide, using freely available satellite imagery, suggests that they might be even more common than previously thought. If so, this confirms that episodic

Probabilistically modeling lava flows with MOLASSES

Science.gov (United States)

Richardson, J. A.; Connor, L.; Connor, C.; Gallant, E.

2017-12-01

Modeling lava flows through Cellular Automata methods enables a computationally inexpensive means to quickly forecast lava flow paths and ultimate areal extents. We have developed a lava flow simulator, MOLASSES, that forecasts lava flow inundation over an elevation model from a point source eruption. This modular code can be implemented in a deterministic fashion with given user inputs that will produce a single lava flow simulation. MOLASSES can also be implemented in a probabilistic fashion where given user inputs define parameter distributions that are randomly sampled to create many lava flow simulations. This probabilistic approach enables uncertainty in input data to be expressed in the model results and MOLASSES outputs a probability map of inundation instead of a determined lava flow extent. Since the code is comparatively fast, we use it probabilistically to investigate where potential vents are located that may impact specific sites and areas, as well as the unconditional probability of lava flow inundation of sites or areas from any vent. We have validated the MOLASSES code to community-defined benchmark tests and to the real world lava flows at Tolbachik (2012-2013) and Pico do Fogo (2014-2015). To determine the efficacy of the MOLASSES simulator at accurately and precisely mimicking the inundation area of real flows, we report goodness of fit using both model sensitivity and the Positive Predictive Value, the latter of which is a Bayesian posterior statistic. Model sensitivity is often used in evaluating lava flow simulators, as it describes how much of the lava flow was successfully modeled by the simulation. We argue that the positive predictive value is equally important in determining how good a simulator is, as it describes the percentage of the simulation space that was actually inundated by lava.

Sulphur in liquid fuels 2002

Energy Technology Data Exchange (ETDEWEB)

Guthrie, J. [Environment Canada, Gatineau, PQ (Canada). Fuels Div., Oil, Gas and Energy Branch ; Sabourin, R. [Carleton Univ., Ottawa, ON (Canada)

2003-08-01

Environment Canada has developed new regulations for sulphur content in fuels in an effort to align with requirements recently passed by the U.S. Environmental Protection Agency. This report summarizes data regarding sulphur content in liquid fuels for the year 2002. The requirements of the Sulphur in Gasoline Regulation came into effect in 2002, limiting the average sulphur content of gasoline to 150 mg/kg. In January 2005, a 30 mg/kg average limit will come into effect. Also, in July 2002, the Sulphur in Diesel Fuel Regulation stipulated a maximum limit of 500 mg/kg for on-road diesel fuel. The new regulation continues this limit until mid-2006 at which time a 15 mg/kg limit will come into effect for on-road diesel fuel. Nationally, the average sulphur content in gasoline in 2002 was 246 mg/kg, which was 14.3 per cent lower than in 2001. The data covers the period from January 1 to December 31, 2002 and was obtained from petroleum refineries and importing companies that are required to submit quarterly information to the regional office of Environment Canada. Failure to comply results in penalties. The report includes data for aviation turbo fuel, motor gasoline, aviation gasoline, kerosene oil, low-sulphur diesel fuel, diesel fuel, light fuel oil, and heavy fuel oil. 16 tabs., 17 figs., 7 appendices.

Modeling Submarine Lava Flow with ASPECT

Science.gov (United States)

Storvick, E. R.; Lu, H.; Choi, E.

2017-12-01

Submarine lava flow is not easily observed and experimented on due to limited accessibility and challenges posed by the fast solidification of lava and the associated drastic changes in rheology. However, recent advances in numerical modeling techniques might address some of these challenges and provide unprecedented insight into the mechanics of submarine lava flow and conditions determining its wide-ranging morphologies. In this study, we explore the applicability ASPECT, Advanced Solver for Problems in Earth's ConvecTion, to submarine lava flow. ASPECT is a parallel finite element code that solves problems of thermal convection in the Earth's mantle. We will assess ASPECT's capability to model submarine lava flow by observing models of lava flow morphology simulated with GALE, a long-term tectonics finite element analysis code, with models created using comparable settings and parameters in ASPECT. From these observations we will contrast the differing models in order to identify the benefits of each code. While doing so, we anticipate we will learn about the conditions required for end-members of lava flow morphology, for example, pillows and sheet flows. With ASPECT specifically we focus on 1) whether the lava rheology can be implemented; 2) how effective the AMR is in resolving morphologies of the solidified crust; 3) whether and under what conditions the end-members of the lava flow morphologies, pillows and sheets, can be reproduced.

Eruptive behavior of the Marum/Mbwelesu lava lake, Vanuatu and comparisons with lava lakes on Earth and Io

Science.gov (United States)

Radebaugh, Jani; Lopes, Rosaly M.; Howell, Robert R.; Lorenz, Ralph D.; Turtle, Elizabeth P.

2016-08-01

Observations from field remote sensing of the morphology, kinematics and temperature of the Marum/Mbwelesu lava lake in the Vanuatu archipelago in 2014 reveal a highly active, vigorously erupting lava lake. Active degassing and fountaining observed at the 50 m lava lake led to large areas of fully exposed lavas and rapid ( 5 m/s) movement of lava from the centers of upwelling outwards to the lake margins. These rapid lava speeds precluded the formation of thick crust; there was never more than 30% non-translucent crust. The lava lake was observed with several portable, handheld, low-cost, near-infrared imagers, all of which measured temperatures near 1000 °C and one as high as 1022 °C, consistent with basaltic temperatures. Fine-scale structure in the lava fountains and cooled crust was visible in the near infrared at 5 cm/pixel from 300 m above the lake surface. The temperature distribution across the lake surface is much broader than at more quiescent lava lakes, peaking 850 °C, and is attributed to the highly exposed nature of the rapidly circulating lake. This lava lake has many characteristics in common with other active lava lakes, such as Erta Ale in Ethiopia, being confined, persistent and high-temperature; however it was much more active than is typical for Erta Ale, which often has > 90% crust. Furthermore, it is a good analogue for the persistent, high-temperature lava lakes contained within volcanic depressions on Jupiter's moon Io, such as Pele, also believed from spacecraft and ground-based observations to exhibit similar behavior of gas emission, rapid overturn and fountaining.

Correlation of the Deccan and Rajahmundry Trap lavas: Are these the longest and largest lava flows on Earth?

Science.gov (United States)

Self, S.; Jay, A. E.; Widdowson, M.; Keszthelyi, L. P.

2008-05-01

We propose that the Rajahmundry Trap lavas, found near the east coast of peninsular India , are remnants of the longest lava flows yet recognized on Earth (˜ 1000 km long). These outlying Deccan-like lavas are shown to belong to the main Deccan Traps. Several previous studies have already suggested this correlation, but have not demonstrated it categorically. The exposed Rajahmundry lavas are interpreted to be the distal parts of two very-large-volume pāhoehoe flow fields, one each from the Ambenali and Mahabaleshwar Formations of the Wai Sub-group in the Deccan Basalt Group. Eruptive conditions required to emplace such long flows are met by plausible values for cooling and eruption rates, and this is shown by applying a model for the formation of inflated pāhoehoe sheet flow lobes. The model predicts flow lobe thicknesses similar to those observed in the Rajahmundry lavas. For the last 400 km of flow, the lava flows were confined to the pre-existing Krishna valley drainage system that existed in the basement beyond the edge of the gradually expanding Deccan lava field, allowing the flows to extend across the subcontinent to the eastern margin where they were emplaced into a littoral and/or shallow marine environment. These lavas and other individual flow fields in the Wai Sub-group may exceed eruptive volumes of 5000 km 3, which would place them amongst the largest magnitude effusive eruptive units yet known. We suggest that the length of flood basalt lava flows on Earth is restricted mainly by the size of land masses and topography. In the case of the Rajahmundry lavas, the flows reached estuaries and the sea, where their advance was perhaps effectively terminated by cooling and/or disruption. However, it is only during large igneous province basaltic volcanism that such huge volumes of lava are erupted in single events, and when the magma supply rate is sufficiently high and maintained to allow the formation of very long lava flows. The Rajahmundry lava

Hydrothermal Alteration in an Acid-Sulphate Geothermal Field: Sulphur Springs, Saint Lucia

Science.gov (United States)

Joseph, E. P.; Barrett, T. J.

2017-12-01

Sulphur Springs is a vigorous geothermal field associated with the Soufrière Volcanic Centre in southern Saint Lucia. Bubbling hydrothermal pools are rich in sodium-calcium sulphate, with pHs of 3-7 and temperatures of 41-97ºC. Fumaroles have temperatures up to, and at times above, 100°C. Gases from bubbling pools and fumaroles have high contents of CO2 (601-993 mmol/mol) and H2S (3-190 mmol/mol). To investigate the nature and extent of hydrothermal alteration, detailed chemical analysis was carried out on 25 altered rocks, 10 sediments from pools and creeks in the main discharge area, and 15 little-altered rocks up to 2 km away from geothermal field. Eight altered samples were also analysed for stable isotope compositions, with mineralogy determined by X-ray diffraction and mineral liberation analysis. Least-altered host rocks comprise calc-alkaline feldspar-quartz-porphyritic dacites of near-uniform composition that form massive domes and volcaniclastic units. These rocks were emplaced 10-30 Ka ago (Lindsay et al. 2013). Within the geothermal field, the dacites have been highly altered to kaolinite, quartz, cristobalite, alunite, natroalunite, smectite, native sulphur, jarosite, gypsum and amorphous compounds. Muds from grey to blackish hydrothermal pools additionally contain iron sulphides, mainly pyrite. Despite intense alteration of the original dacites, Zr and Ti have remained essentially immobile, allowing the calculation of mass changes. Major depletions of Fe, Mg, Ca, Na and commonly Si occur over an area of at least 200 x 400 m. The most altered rocks also show losses of Al, light REE and Y, implying leaching by highly acidic waters. A few altered rocks have, however, gained Al together with Si and P. Also present are m-scale zones of silica + native sulphur, wherein the silica appears to represent a residue from the leaching of dacite, rather than a hydrothermal addition. Delta-34S values of samples containing mixtures of sulphates, native sulphur and

Removing sulphur oxides from a fluid stream

Science.gov (United States)

Katz, Torsten; Riemann, Christian; Bartling, Karsten; Rigby, Sean Taylor; Coleman, Luke James Ivor; Lail, Marty Alan

2014-04-08

A process for removing sulphur oxides from a fluid stream, such as flue gas, comprising: providing a non-aqueous absorption liquid containing at least one hydrophobic amine, the liquid being incompletely miscible with water; treating the fluid stream in an absorption zone with the non-aqueous absorption liquid to transfer at least part of the sulphur oxides into the non-aqueous absorption liquid and to form a sulphur oxide-hydrophobic amine-complex; causing the non-aqueous absorption liquid to be in liquid-liquid contact with an aqueous liquid whereby at least part of the sulphur oxide-hydrophobic amine-complex is hydrolyzed to release the hydrophobic amine and sulphurous hydrolysis products, and at least part of the sulphurous hydrolysis products is transferred into the aqueous liquid; separating the aqueous liquid from the non-aqueous absorption liquid. The process mitigates absorbent degradation problems caused by sulphur dioxide and oxygen in flue gas.

What factors control superficial lava dome explosivity?

Science.gov (United States)

Boudon, Georges; Balcone-Boissard, Hélène; Villemant, Benoît; Morgan, Daniel J

2015-09-30

Dome-forming eruption is a frequent eruptive style and a major hazard on numerous volcanoes worldwide. Lava domes are built by slow extrusion of degassed, viscous magma and may be destroyed by gravitational collapse or explosion. The triggering of lava dome explosions is poorly understood: here we propose a new model of superficial lava-dome explosivity based upon a textural and geochemical study (vesicularity, microcrystallinity, cristobalite distribution, residual water contents, crystal transit times) of clasts produced by key eruptions. Superficial explosion of a growing lava dome may be promoted through porosity reduction caused by both vesicle flattening due to gas escape and syn-eruptive cristobalite precipitation. Both processes generate an impermeable and rigid carapace allowing overpressurisation of the inner parts of the lava dome by the rapid input of vesiculated magma batches. The relative thickness of the cristobalite-rich carapace is an inverse function of the external lava dome surface area. Explosive activity is thus more likely to occur at the onset of lava dome extrusion, in agreement with observations, as the likelihood of superficial lava dome explosions depends inversely on lava dome volume. This new result is of interest for the whole volcanological community and for risk management.

Miocene Basaltic Lava Flows and Dikes of the Intervening Area Between Picture Gorge and Steens Basalt of the CRBG, Eastern Oregon

Science.gov (United States)

Cahoon, E. B.; Streck, M. J.

2016-12-01

Mid-Miocene basaltic lavas and dikes are exposed in the area between the southern extent of the Picture Gorge Basalt (PGB) and the northern extent of Steens Basalt in a wide corridor of the Malheur National Forest, eastern Oregon. An approximate mid-Miocene age of sampled basaltic units is indicated by stratigraphic relationships to the 16 Ma Dinner Creek Tuff. Lavas provide an opportunity to extend and/or revise distribution areas of either CRBG unit and explore the petrologic transition between them. The PGB and the Steens Basalt largely represent geochemically distinct tholeiitic units of the CRBG; although each unit displays internal complexity. Lavas of PGB are relatively primitive (MgO 5-9 wt.%) while Steens Basalt ranges in MgO from >9 to 3 wt.% but both units are commonly coarsely porphyritic. Conversely, Steens Basalt compositions are on average more enriched in highly incompatible elements (e.g. Rb, Th) and relatively enriched in the lesser incompatible elements (e.g. Y, Yb) compared to the Picture Gorge basalts. These compositional signatures produce inclined and flat patterns on mantle-normalized incompatible trace element plots but with similar troughs and spikes, respectively. New compositional data from our study area indicate basaltic lavas can be assigned as PGB lava flows and dikes, and also to a compositional group chemically distinct between Steens Basalt and PGB. Distribution of lava flows with PGB composition extend this CRBG unit significantly south/southeast closing the exposure gap between PGB and Steens Basalt. We await data that match Steens Basalt compositions but basaltic lavas with petrographic features akin to Steens Basalt have been identified in the study area. Lavas of the transitional unit share characteristics with Upper Steens and Picture Gorge basalt types, but identify a new seemingly unique composition. This composition is slightly more depleted in the lesser incompatible elements (i.e. steeper pattern) on mantle normalized

Sulphur fertilization influences the sulphur species composition in Allium sativum: sulphomics using HPLC-ICPMS/MS-ESI-MS/MS.

Science.gov (United States)

Raab, Andrea; Ronzan, Marilena; Feldmann, Joerg

2017-10-18

Garlic (A. sativum) contains a large number of small sulphur (S)-containing metabolites, which are important for its taste and smell and vary with A. sativum variety and growth conditions. This study was designed to investigate the influence of different sulphur-fertilization regimes on low molecular weight S-species by attempting the first sulphur mass balance in A. sativum roots and bulbs using HPLC-ICPMS/MS-ESI-MS/MS. Species unspecific quantification of acid soluble S-containing metabolites was achieved using HPLC-ICP-MS/MS. For identification of the compounds, high resolution ESI-MS (Orbitrap LTQ and q-TOF) was used. The plants contained up to 54 separated sulphur-containing compounds, which constitute about 80% of the total sulphur present in A. sativum. The roots and bulbs of A. sativum contained the same compounds, but not necessarily the same amounts and proportions. The S-containing metabolites in the roots reacted more sensitively to manipulations of sulphur fertilization than those compounds in the bulbs. In addition to known compounds (e.g. γ-glutamyl-S-1-propenylcysteine) we were able to identify and partially quantify 31 compounds. Three as yet undescribed S-containing compounds were also identified and quantified for the first time. Putative structures were assigned to the oxidised forms of S-1-propenylmercaptoglutathione, S-2-propenylmercaptoglutathione, S-allyl/propenyl-containing PC-2 and 2-amino-3-[(2-carboxypropyl)sulfanyl]propanoic acid. The parallel use of ICP-MS/MS as a sulphur-specific detector and ESI-MS as a molecular detector simplifies the identification and quantification of sulphur containing metabolites without species specific standards. This non-target analysis approach enables a mass balance approach and identifies the occurrence of the so far unidentified organosulphur compounds. The experiments showed that the sulphur-fertilization regime does not influence sulphur-speciation, but the concentration of some S

Effects of sulphur ion implantation on the electrochemical behaviour of two stainless steels in sulphuric medium

International Nuclear Information System (INIS)

Nader-Roux, J.; Becdelievre, A.M. de; Gaillard, F.; Roux, R.; Becdelievre, J. de

1986-01-01

The electrochemical behaviour in sulphuric acid of two austenitic stainless steels (AISI 304 L and AISI 321) modified by sulphur ion implantation has been studied. Surface analysis of oxygen and sulphur by LEEIXS and XRFS were performed before and after polarization on unimplanted and on implanted samples. I/E curves with implanted steels reveal an important corrosion peak (α peak) recovering widely the active peak of unimplanted samples. For high implanted doses, another peak (β peak) appears in the passive range. High doses implanted steels polarized in the range of the α peak exhibit a sulphur enriched black surface layer. SEM examination of this layer shows it is constituted by flakes rolling up themselves. The formation of a superficial non-protective sulphide layer and the internal stresses of this layer explain the corrosion enhancement of sulphur implanted materials. After dissolution of this layer the behaviour of unimplanted steels is found again. (author)

Remote sensing evidence of lava-ground ice interactions associated with the Lost Jim Lava Flow, Seward Peninsula, Alaska

Science.gov (United States)

Marcucci, Emma C.; Hamilton, Christopher W.; Herrick, Robert R.

2017-12-01

Thermokarst terrains develop when ice-bearing permafrost melts and causes the overlying surface to subside or collapse. This process occurs widely throughout Arctic regions due to environmental and climatological factors, but can also be induced by localized melting of ground ice by active lava flows. The Lost Jim Lava Flow (LJLF) on the Seward Peninsula of Alaska provides evidence of former lava-ground ice interactions. Associated geomorphic features, on the scale of meters to tens of meters, were identified using satellite orthoimages and stereo-derived digital terrain models. The flow exhibits positive- and mixed-relief features, including tumuli ( N = 26) and shatter rings ( N = 4), as well as negative-relief features, such as lava tube skylights ( N = 100) and irregularly shaped topographic depressions ( N = 1188) that are interpreted to include lava-rise pits and lava-induced thermokarst terrain. Along the margins of the flow, there are also clusters of small peripheral pits that may be the products of meltwater or steam escape. On Mars, we observed morphologically similar pits near lava flow margins in northeastern Elysium Planitia, which suggests a common formation mechanism. Investigating the LJLF may therefore help to elucidate processes of lava-ground ice interaction on both Earth and Mars.

Changes in the content of water-soluble sulphur in the soil after an application of straw and elemental sulphur

Directory of Open Access Journals (Sweden)

Pavel Ryant

2007-01-01

Full Text Available The changes in the content of water-soluble sulphur in the soil after the application of straw and elemental sulphur (ES were explored in a 2-year vegetation pot experiment. The following variants were included in the experiment: 1 unfertilised control; 2 wheat straw; 3 rape straw; 4 ES; 5 wheat straw + ES; 6 rape straw + ES. The two types of straw were applied in a dose of 32 g of dry matter and elemental sulphur was applied in a dose of 0.42 g per pot, i.e. 6 kg of soil. The unsatisfactory C:N ratio in the straw was optimised to 25:1 by adding nitrogen in urea. Soil samples were taken prior to sowing of the model plant (spring wheat in 2005 and white mustard in 2006 and then in regular monthly intervals until harvesting (5 times a year. The content of water-soluble sulphur in the soil was evaluated by multifactorial analysis of variance monitoring the effect of the crop, date of soil sampling, application of straw and elemental sulphur.The contents of water-soluble sulphur differed statistically significantly (P > 0.999 when growing the individual model plants. When growing white mustard in 2006 the amount of available sulphur was by 1/5 higher and could have been partly affected by the warm year 2006, as compared to 2005 when spring wheat was grown. Significant differences (P > 0.999 were also discovered among the dates of soil sampling; higher values were detected before the sowing of model plants, i.e. after incubation in the winter, during vegetation the content of water-soluble sulphur decreased and sulphur showed the significantly highest values at the harvest of model plants. When wheat straw was applied the sulphur content did not increase and this may be associated with the wide C:S ratio, whereas after the application of rape straw the content of water-soluble sulphur increased by one third more than in the unfertilised control. The application of elemental sulphur also significantly increased the amount of water-soluble sulphur in

Quantitative Aspects of Sulphur Metabolism in the Ruminant

Energy Technology Data Exchange (ETDEWEB)

Landis, J. [Institut fuer Tierernaehrung, Eidgenoessische Technische Hochschule, Zurich (Switzerland)

1968-07-01

In a series of four experiments {sup 35}S sulphate was given intra-ruminally to lactating dairy goats at feeding times (twice daily) during periods of 10 to 11 d. Rumen contents were sampled on the 8th, 9th and 10th day of {sup 35}S application. Radioactivity was determined in the volatile sulphur fraction (sulphide-sulphur) and in protein-bound sulphur (fraction insoluble in trichloroacetic acid). The ratio between the specific activities of protein sulphur and of sulphide sulphur was considered to be an estimate for that fraction of sulphur-containing amino acids present in the proteins of rumen contents, which was synthesized by microorganisms. This interpretation is based on the assumption that sulphide is the most important source of inorganic sulphur for the synthesis of sulphur amino acids and that incorporation of inorganic sulphur compounds of a a higher state of oxidation into organic molecules may quantitatively be neglected. In three experiments the animals received rations containing 16% to 17% crude protein. In these experiments the ratio of specific activities of protein and sulphide sulphur was found to vary from 0.32 to 0.41. According to the assumptions mentioned above, this would indicate that 32 to 41% of the total amount of protein-bound sulphur amino acids were synthesized by microorganisms from inorganic (sulphide) sulphur. In the fourth experiment the animal received a ration containing only 10% protein but supplemented with urea to bring the total crude protein content to 13%. In this experiment the ratio of specific activities was 0.70, indicating a much higher contribution of microbial synthesis of sulphur amino acids than in the experiments with a more abundant protein supply. The time course of the specific activity of protein-bound-sulphur in the milk is taken as a reference base for an interpretation of labelling of body proteins in terms of turnover rates.

Lava tubes - Potential shelters for habitats

Science.gov (United States)

Horz, F.

Natural caverns occur on the moon in the form of 'lava tubes', which are the drained conduits of underground lava rivers. The inside dimensions of these tubes measure tens to hundreds of meters, and their roofs are expected to be thicker than 10 meters. Consequently, lava tube interiors offer an environment that is naturally protected from the hazards of radiation and meteorite impact. Further, constant, relatively benign temperatures of -20 C prevail. These are extremely favorable environmental conditions for human activities and industrial operations. Significant operational, technological, and economical benefits might result if a lunar base were constructed inside a lava tube.

Sulphur capture by co-firing sulphur containing fuels with biomass fuels - optimization

International Nuclear Information System (INIS)

Nordin, A.

1992-12-01

Previous results concerning co-firing of high sulphur fuels with biomass fuels have shown that a significant part of the sulphur can be absorbed in the ash by formation of harmless sulphates. The aim of this work has been to (i) determine the maximum reduction that can be obtained in a bench scaled fluidized bed (5 kW); (ii) determine which operating conditions will give maximum reduction; (iii) point out the importance and applicability of experimental designs and multivariate methods when optimizing combustion processes; (iv) determine if the degree of sulphur capture can be correlated to the degree of slagging, fouling or bed sintering; and (v) determine if further studies are desired. The following are some of the more important results obtained: - By co-firing peat with biomass, a total sulphur retention of 70 % can be obtained. By co-firing coal with energy-grass, the total SO 2 emissions can be reduced by 90 %. - Fuel feeding rate, amount of combustion air and the primary air ratio were the most important operating parameters for the reduction. Bed temperature and oxygen level seem to be the crucial physical parameters. - The NO emissions also decreased by the sulphur reducing measures. The CO emissions were relatively high (130 mg/MJ) compared to large scale facilities due to the small reactor and the small fluctuations in the fuel feeding rate. The SO 2 emissions could however be reduced without any increase in CO emissions. - When the reactor was fired with a grass, the bed sintered at a low temperature ( 2 SO 4 and KCl are formed no sintering problems were observed. (27 refs., 41 figs., 9 tabs., 3 appendices)

Cyclic pressurisation of Mount St Helens dacites and basalt. Laboratory results and implications for lava dome monitoring

Science.gov (United States)

Kendrick, Jackie; Dainty, Matthew; Smith, Rosanna; Sammonds, Peter; Pallister, John; Meredith, Phillip

2010-05-01

Lava domes are frequently subjected to cyclic heating and pressurisation, which may weaken the dome rocks, leading to renewed extrusion, explosions or collapse. These heating and loading cycles can be recreated in the laboratory, allowing the level of crack damage caused by these cycles to be established through analysing elastic moduli. Acoustic emissions (AEs) indicate the timing of cracking, and can also be used to interpret precursory seismicity for eruption prediction. Experiment samples are from Mount St. Helens, USA: 3 dacites from the Pine Creek eruptive period (2.9-2.55 ka), a Castle Creek age basalt (2.55-1.895 ka), and 4 dacites from the 2004-2008 eruption. Each sample was cut into several cylindrical cores (25 mm diameter and 62.5-70 mm long). Some samples were then heated and cooled at 1˚C/ minute to a target temperature of 600o C or 900o C, and held for 2 hours to achieve thermal equilibrium. This heating can cause cracking due to contrasts in thermal expansion of different minerals. Dynamic elastic moduli were calculated for each sample using ultrasonic wave velocity, density and porosity for later comparison to static elastic moduli gathered during deformation. One core of each sample was loaded to failure in uniaxial compression in order to find the short term strength of the sample. For all cyclic loading tests, conducted on pre-heated and unheated cores, samples were loaded at 10-5 s-1 strain rate then unloaded to 5MPa. Subsequent cycles had an increasing peak load. Most had the same rate for unloading, with a few samples unloaded instantaneously. Axial, radial and volumetric strain were determined from the recorded displacement throughout the experiment and used with the axial stress measurements to calculate static elastic moduli. Samples loaded to failure with no cycling generally failed at higher stresses than their cyclically loaded counter-parts, whilst rapid unloading increased their strength. Failure stresses of the dacite lava dome

CLINSULF sub-dew-point process for sulphur recovery

Energy Technology Data Exchange (ETDEWEB)

Heisel, M.; Marold, F.

1988-01-01

In a 2-reactor system, the CLINSULF process allows very high sulphur recovery rates. When operated at 100/sup 0/C at the outlet, i.e. below the sulphur solidification point, a sulphur recovery rate of more than 99.2% was achieved in a 2-reactor series. Assuming a 70% sulphur recovery in an upstream Claus furnace plus sulphur condenser, an overall sulphur recovery of more than 99.8% results for the 2-reactor system. This is approximately 2% higher than in conventional Claus plus SDP units, which mostly consist of 4 reactors or more. This means the the CLINSULF SSP process promises to be an improvement both in respect of efficiency and low investment cost.

Sulphurous Mineral Waters: New Applications for Health

Directory of Open Access Journals (Sweden)

Jose Manuel Carbajo

2017-01-01

Full Text Available Sulphurous mineral waters have been traditionally used in medical hydrology as treatment for skin, respiratory, and musculoskeletal disorders. However, driven by recent intense research efforts, topical treatments are starting to show benefits for pulmonary hypertension, arterial hypertension, atherosclerosis, ischemia-reperfusion injury, heart failure, peptic ulcer, and acute and chronic inflammatory diseases. The beneficial effects of sulphurous mineral waters, sulphurous mud, or peloids made from sulphurous mineral water have been attributed to the presence of sulphur mainly in the form of hydrogen sulphide. This form is largely available in conditions of low pH when oxygen concentrations are also low. In the organism, small amounts of hydrogen sulphide are produced by some cells where they have numerous biological signalling functions. While high levels of hydrogen sulphide are extremely toxic, enzymes in the body are capable of detoxifying it by oxidation to harmless sulphate. Hence, low levels of hydrogen sulphide may be tolerated indefinitely. In this paper, we review the chemistry and actions of hydrogen sulphide in sulphurous mineral waters and its natural role in body physiology. This is followed by an update of available data on the impacts of exogenous hydrogen sulphide on the skin and internal cells and organs including new therapeutic possibilities of sulphurous mineral waters and their peloids.

Sulphur removal in IGCC projects

Energy Technology Data Exchange (ETDEWEB)

Cross, F. (Parsons (United Kingdom))

1998-01-01

The technology for recovering elemental sulphur from H[sub 2]S bearing gases is well established. The modified Claus Process is the principal work-horse in sulphur recovery and can customarily achieve conversion efficiencies of 95% or better. Nowadays, such a level of recovery is no longer sufficient in most instances and sulphur recovery facility must then include some form of enhanced recovery, usually by treating the Claus tail gas. A number of processes have been introduced to enable the overall recovery to be increased. Recoveries in excess of 99% are both feasible and economic. Use of oxygen in place has become very popular in cases where oxygen is available cheaply or where capacity increases are designed. Most IGCC projects needing an air separation plant would automatically benefit from extending the use of oxygen to the sulphur recovery plant. The most popular route to minimising sulphur emissions in the context of IGCC projects has involved an oxygen based Claus plant followed by tail gas hydrogenation, hydrogen sulphide recovery and its recycle to the Claus section. The recovery of H[sub 2]S from the Claus tail gas can be integrated with the main gas treating system in the gasification plant. The cost advantage of doing so is significant. Parsons has been involved with the technology since 1949 and has been responsible for developments such as the ammonia burning Claus and jointly with Unocal, the BSRP tail gas process and Selectox processes. Recent innovations in response changing environmental and production requirements have included catalytic and tail gas processes which reduce sulphur emissions. 6 figs., 2 tabs.

Sulphur removal in IGCC projects

Energy Technology Data Exchange (ETDEWEB)

Cross, F. [Parsons (United Kingdom)

1998-12-31

The technology for recovering elemental sulphur from H{sub 2}S bearing gases is well established. The modified Claus Process is the principal work-horse in sulphur recovery and can customarily achieve conversion efficiencies of 95% or better. Nowadays, such a level of recovery is no longer sufficient in most instances and sulphur recovery facility must then include some form of enhanced recovery, usually by treating the Claus tail gas. A number of processes have been introduced to enable the overall recovery to be increased. Recoveries in excess of 99% are both feasible and economic. Use of oxygen in place has become very popular in cases where oxygen is available cheaply or where capacity increases are designed. Most IGCC projects needing an air separation plant would automatically benefit from extending the use of oxygen to the sulphur recovery plant. The most popular route to minimising sulphur emissions in the context of IGCC projects has involved an oxygen based Claus plant followed by tail gas hydrogenation, hydrogen sulphide recovery and its recycle to the Claus section. The recovery of H{sub 2}S from the Claus tail gas can be integrated with the main gas treating system in the gasification plant. The cost advantage of doing so is significant. Parsons has been involved with the technology since 1949 and has been responsible for developments such as the ammonia burning Claus and jointly with Unocal, the BSRP tail gas process and Selectox processes. Recent innovations in response changing environmental and production requirements have included catalytic and tail gas processes which reduce sulphur emissions. 6 figs., 2 tabs.

Ridge-like lava tube systems in southeast Tharsis, Mars

Science.gov (United States)

Zhao, Jiannan; Huang, Jun; Kraft, Michael D.; Xiao, Long; Jiang, Yun

2017-10-01

Lava tubes are widely distributed in volcanic fields on a planetary surface and they are important means of lava transportation. We have identified 38 sinuous ridges with a lava-tube origin in southeast Tharsis. The lengths vary between 14 and 740 km, and most of them occur in areas with slopes rate, low lava viscosity, and sustained magma supply during a long period. Besides, lava flow inflation is also important in the formation of the ridge-like lava tubes and some associated features. These lava tubes provide efficient lateral pathways for magma transportation over the relatively low topographic slopes in southeast Tharsis, and they are important for the formation of long lava flows in this region. The findings of this study provide an alternative formation mechanism for sinuous ridges on the martian surface.

Astrobiology Training in Lava Tubes (ATiLT): Characterizing coralloid speleothems in basaltic lava tubes as a Mars analogue

Science.gov (United States)

Ni, J.; Leveille, R. J.; Douglas, P.

2017-12-01

Coralloid speleothems or cave corals are small mineralised nodes that can take a variety of forms, and which develop through groundwater seepage and water-rock interaction in caves. They are found commonly on Earth in a plethora of caves, including lava tubes. Since lava tubes have been identified on the surface of Mars from remotely sensed images, there has been interest in studying Earth's lava tube systems as an analogue for understanding Martian lava environments. If cave minerals were found on Mars, they could indicate past or present water-rock interaction in the Martian subsurface. Martian lava tubes could also provide insights into habitable subsurface environments as well as conditions favourable for the synthesis and preservation of biosignatures. One of the aims of the Astrobiology Training in Lava Tubes (ATiLT) project is to analyze biosignatures and paleoenvironmental indicators in secondary cave minerals, which will be looked at in-situ and compared to collected field samples. In this study, secondary mineralization in lava cave systems from Lava Beds National Monument, CA is examined. In the field, coralloid speleothems have been observed growing on all surfaces of the caves, including cave ceilings, floors, walls and overhangs. They are also observed growing adjacent to biofilms, which sometimes fill in the cracks of the coralloid nodes. Preliminary results show the presence of opal, calcite, quartz and other minor minerals in the speleothems. This study seeks to understand the formation mechanism and source of these secondary minerals, as well as determine their possible relation to the biofilms. This will be done through the analysis of the water chemistry, isotope geochemistry and microscale mineralogy.

Impact of pedospheric and atmospheric sulphur nutrition on sulphur metabolism of Allium cepa L., a species with a potential sink capacity for secondary sulphur compounds

NARCIS (Netherlands)

Durenkamp, M.; De Kok, L.J.

Onion (Afflum cepa L.) was able to use atmospheric H2S as sole sulphur source for growth. The foliarly absorbed H2S was rapidly metabolized into water-soluble, non-protein thiol compounds, including cysteine, and subsequently into other sulphur compounds in the shoots. In H2S-exposed plants, the

What factors control the superficial lava dome explosivity?

Science.gov (United States)

Boudon, Georges; Balcone-Boissard, Hélène; Villemant, Benoit; Morgan, Daniel J.

2015-04-01

Dome-forming eruption is a frequent eruptive style; lava domes result from intermittent, slow extrusion of viscous lava. Most dome-forming eruptions produce highly microcrystallized and highly- to almost totally-degassed magmas which have a low explosive potential. During lava dome growth, recurrent collapses of unstable parts are the main destructive process of the lava dome, generating concentrated pyroclastic density currents (C-PDC) channelized in valleys. These C-PDC have a high, but localized, damage potential that largely depends on the collapsed volume. Sometimes, a dilute ash cloud surge develops at the top of the concentrated flow with an increased destructive effect because it may overflow ridges and affect larger areas. In some cases, large lava dome collapses can induce a depressurization of the magma within the conduit, leading to vulcanian explosions. By contrast, violent, laterally directed, explosions may occur at the base of a growing lava dome: this activity generates dilute and turbulent, highly-destructive, pyroclastic density currents (D-PDC), with a high velocity and propagation poorly dependent on the topography. Numerous studies on lava dome behaviors exist, but the triggering of lava dome explosions is poorly understood. Here, seven dome-forming eruptions are investigated: in the Lesser Antilles arc: Montagne Pelée, Martinique (1902-1905, 1929-1932 and 650 y. BP eruptions), Soufrière Hills, Montserrat; in Guatemala, Santiaguito (1929 eruption); in La Chaîne des Puys, France (Puy de Dome and Puy Chopine eruptions). We propose a new model of superficial lava-dome explosivity based upon a textural and geochemical study (vesicularity, microcrystallinity, cristobalite distribution, residual water contents, crystal transit times) of clasts produced by these key eruptions. Superficial explosion of a growing lava dome may be promoted through porosity reduction caused by both vesicle flattening due to gas escape and syn-eruptive cristobalite

Impact of sulphur fumigation on the chemistry of ginger.

Science.gov (United States)

Wu, Cheng-Ying; Kong, Ming; Zhang, Wei; Long, Fang; Zhou, Jing; Zhou, Shan-Shan; Xu, Jin-Di; Xu, Jun; Li, Song-Lin

2018-01-15

Ginger (Zingiberis Rhizoma), a commonly-consumed food supplement, is often sulphur-fumigated during post-harvest handling, but it remains unknown if sulphur fumigation induces chemical transformations in ginger. In this study, the effects of sulphur fumigation on ginger chemicals were investigated by ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS/MS)-based metabolomics. The results showed that sulphur fumigation significantly altered the holistic chemical profile of ginger by triggering chemical transformations of certain original components. 6-Gingesulphonic acid, previously reported as a naturally-occurring component in ginger, was revealed to be a sulphur fumigation-induced artificial derivative, which was deduced to be generated by electrophilic addition of 6-shogaol to sulphurous acid. Using UHPLC-QTOF-MS/MS extracting ion analysis with 6-gingesulphonic acid as a characteristic chemical marker, all the commercial ginger samples inspected were determined to be sulphur-fumigated. The research outcomes provide a chemical basis for further comprehensive safety and efficacy evaluations of sulphur-fumigated ginger. Copyright © 2017 Elsevier Ltd. All rights reserved.

Sulphur oxidising bacteria in mangrove ecosystem: A review ...

African Journals Online (AJOL)

Sulphur-oxidizing bacteria such as photoautotrophs, chemolithotrophs and heterotrophs play an important role in the mangrove environment for the oxidation of the toxic sulphide produced by sulphur reducing bacteria and act as a key driving force behind all sulphur transformations in the mangrove ecosystem which is ...

A flexible open-source toolkit for lava flow simulations

Science.gov (United States)

Mossoux, Sophie; Feltz, Adelin; Poppe, Sam; Canters, Frank; Kervyn, Matthieu

2014-05-01

Lava flow hazard modeling is a useful tool for scientists and stakeholders confronted with imminent or long term hazard from basaltic volcanoes. It can improve their understanding of the spatial distribution of volcanic hazard, influence their land use decisions and improve the city evacuation during a volcanic crisis. Although a range of empirical, stochastic and physically-based lava flow models exists, these models are rarely available or require a large amount of physical constraints. We present a GIS toolkit which models lava flow propagation from one or multiple eruptive vents, defined interactively on a Digital Elevation Model (DEM). It combines existing probabilistic (VORIS) and deterministic (FLOWGO) models in order to improve the simulation of lava flow spatial spread and terminal length. Not only is this toolkit open-source, running in Python, which allows users to adapt the code to their needs, but it also allows users to combine the models included in different ways. The lava flow paths are determined based on the probabilistic steepest slope (VORIS model - Felpeto et al., 2001) which can be constrained in order to favour concentrated or dispersed flow fields. Moreover, the toolkit allows including a corrective factor in order for the lava to overcome small topographical obstacles or pits. The lava flow terminal length can be constrained using a fixed length value, a Gaussian probability density function or can be calculated based on the thermo-rheological properties of the open-channel lava flow (FLOWGO model - Harris and Rowland, 2001). These slope-constrained properties allow estimating the velocity of the flow and its heat losses. The lava flow stops when its velocity is zero or the lava temperature reaches the solidus. Recent lava flows of Karthala volcano (Comoros islands) are here used to demonstrate the quality of lava flow simulations with the toolkit, using a quantitative assessment of the match of the simulation with the real lava flows. The

Sulphur-containing compounds in sulphur-rich crude oils from hypersaline lake sediments and their geochemical implications

NARCIS (Netherlands)

Sinninghe Damsté, J.S.; Guoying, S.; Jiamo, F.; Brassell, S.C.; Gowar, A.P.; Eglinton, G.; Leeuw, J.W. de; Schenck, P.A.

1987-01-01

Three sulphur-rich commercial crude oils have been studied, which contain sulphur as high as up to 4 —12 %. These samples were collected from Tertiary hypersaline lake sediments of the Jianghan Basin, Hubei Province at different depths, but above the oil generation threshold (2200m). FPD-GC and

Vapor mercury uptake with sulphur impregnated active carbons derived using sulphur dioxide

International Nuclear Information System (INIS)

Tong, S.; Methta, H.; Ahmed, I.; Morris, E.; Fuentes de Maria, L.; Jia, C.Q.

2008-01-01

Active carbon adsorption is the primary technology used for removal of vapour mercury from flue gases in coal-fired power plants, municipal solid waste combustors, and other sources. It can be carried out using two different processes, notably injection of powder active carbon into flue gas streams upstream of the particulate collection devices, and filtration with a granular active carbon fixed bed downstream of the flue gas desulphurization units and/or particulate collectors. This paper presented an investigation of vapour mercury uptake performance of laboratory-made sulphur impregnated active carbons (SIACs) using a fixed bed reactor in a temperature range of 25 to 200 degrees Celsius. The materials and methods as well as the properties of activated carbons studied were presented. The experimental set-up was also described. The paper discussed the effects of initial concentration, the flow rate, the loading amount of SIACs, temperature, and the sulphur impregnation on the mercury uptake performance. The study showed that SIACs produced with sulphur dioxide exhibited a more complicated behaviour when temperature was varied, implying a mixed adsorption mechanism. 10 refs., 3 tabs., 8 figs

The useful application of sulphur-bound waste materials

NARCIS (Netherlands)

Alkemade, M.M.C.; Koene, J.I.A.

1996-01-01

An immobilization process is described which is based on sulphur (instead of cement) as a binding agent for the treatment of hazardous waste materials. Elemental sulphur is able to bind chemically metals such as mercury and, to a lesser extent, lead as metal sulphides. Furthermore, sulphur forms a

Utilization of activated carbon loaded with sulphur for sulphur fertilization in agriculture; Verwertung von mit Schwefel beladener Aktivkohle als Schwefelduenger in der Landwirtschaft

Energy Technology Data Exchange (ETDEWEB)

Kirfel, Kristina; Hoffmann, Heide [Humboldt Univ. Berlin (Germany). AG Agraroekologie und Oekologischer Landbau

2013-01-15

Due to the decrease of atmospheric sulphur deposition, sulphur fertilization has gained significance for agriculture in recent years. Carbon-sulphur-pellets (CSP), activated carbon pellets loaded with sulphur, previously used for desulphurization in biogas plants, are up to now disposed of as waste. In this context the question arises if CSP could be of use for sulphur fertilization of agricultural crops. The objective of this study was to test sulphur release and plant availability from, and plant tolerance towards CSP. A pot experiment using Zea mays with different shares of CSP was carried out. Leaf green intensity of vital plants, indicating plants' current nutritional status, was measured and differences in plant development were documented regularly. At the end of the trial period biomass and elemental contents of the test plants, as well as electrical conductivity and pH-value of the substrate-CSP-mixtures were determined. Amendments of 0.2 m.-% to 1.0 m.-% had a positive effect on plants' dry mass yield; higher shares led to considerable yield losses. By addition of CSP, sulphur content in the plant dry mass increased compared to the control without sulphur fertilization. This result indicates that sulphur adsorbed to activated carbon becomes plant available when applicated to cultural substrate. (orig.)

Taylor instability in rhyolite lava flows

Science.gov (United States)

Baum, B. A.; Krantz, W. B.; Fink, J. H.; Dickinson, R. E.

1989-01-01

A refined Taylor instability model is developed to describe the surface morphology of rhyolite lava flows. The effect of the downslope flow of the lava on the structures resulting from the Taylor instability mechanism is considered. Squire's (1933) transformation is developed for this flow in order to extend the results to three-dimensional modes. This permits assessing why ridges thought to arise from the Taylor instability mechanism are preferentially oriented transverse to the direction of lava flow. Measured diapir and ridge spacings for the Little and Big Glass Mountain rhyolite flows in northern California are used in conjunction with the model in order to explore the implications of the Taylor instability for flow emplacement. The model suggests additional lava flow features that can be measured in order to test whether the Taylor instability mechanism has influenced the flows surface morphology.

Formation of perched lava ponds on basaltic volcanoes: Interaction between cooling rate and flow geometry allows estimation of lava effusion rates

Science.gov (United States)

Wilson, L.; Parfitt, E. A.

1993-01-01

Perched lava ponds are infrequent but distinctive topographic features formed during some basaltic eruptions. Two such ponds, each approximately 150 m in diameter, formed during the 1968 eruption at Napau Crater and the 1974 eruption of Mauna Ulu, both on Kilauea Volcano, Hawaii. Each one formed where a channelized, high volume flux lava flow encountered a sharp reduction of slope: the flow spread out radially and stalled, forming a well-defined terminal levee enclosing a nearly circular lava pond. We describe a model of how cooling limits the motion of lava spreading radially into a pond and compare this with the case of a channelized flow. The difference in geometry has a major effect, such that the size of a pond is a good indicator of the volume flux of the lava forming it. Lateral spreading on distal shallow slopes is a major factor limiting the lengths of lava flows.

Preparation and characterization compatible pellets for immobilization of colloidal sulphur nanoparticles

Science.gov (United States)

Adlim, M.; Zarlaida, F.; Khaldun, I.; Dewi, R.; Jamilah, M.

2018-03-01

Mercury pollution in atmosphere is dominated by mercury vapour release from coal burning and gold-amalgam separation in gold mining. The initial steps in formulating a compatible mercury absorbent for mercury stabilization was fabrication of pellet supported colloidal sulphur. Sulphur is used to stabilize mercury vapour by formation of metacinnabar that has much lower toxicity. The sulphur reactivity toward mercury vapour can be enhanced by using colloidal sulphur nanoparticles immobilized on compatible pellets. Clay pellets would have heat resistance but in fact, they were less stable in aqueous solution although their stability increased with inclusion of rice husk ash and sawdust or pineapple leaf fibre in the composite. Pellets made of rice husk ash and polyvinyl acetate were stable in water at least for 24 hours. Sulphur from thiosulfate precursor that immobilized onto surface of pellet using chitosan as the stabilizer and the binding agent gave lower sulphur content compared to sulphur from other precursors (sulphur powder and sulphur-CS2). Sulphur from thiosulfate precursor was in form of colloid, has nanosize, and disperse particles on the surface of rice husk ash pellets. Sulphur immobilization methods affect on sulphur particles exposure on the pellet surface.

Nuclear physical express analysis of solid fuel sulphur content

International Nuclear Information System (INIS)

Pak, Yu.; Ponomaryova, M

2005-01-01

Full text: Sulphur content is an important qualitative coal parameter. The problem of coal sulphur content determining remains one of the most important both in Kazakhstan and in other coal-mining countries. The traditional method of sampling, the final stage of which is chemical analysis of coal for sulphur, is characterized by high labour intensity and low productivity. That's why it is ineffective for mass express analytical quality control and technological schemes of coal processing control. In this connection it is very urgent to develop a method of coal sulphur content on the base of a series nuclear-geophysical equipment with an isotope source of primary radiation, allowing to increase analysis representativity and maximally take into account coal real composition inconstancy. To solve the problem set it is necessary to study the main laws of X-ray-radiometric method applied to the coal quality analysis for working out instrumental methods of speed determining of coal sulphur content with satisfactory accuracy for technological tasks, to determine laws of changing the flows of characteristic X-ray and scattered radiation from coal sulphur content of various real composition and to optimize methodical and hardware parameters, providing minimal error of sulphur content control. On the base of studying laws of real composition coal components and their interconnections with sulphur content there has been substantiated the expediency of using hardware functions of calcium and iron to control coal sulphur contents; there has been suggested a model to estimate the methodical error of coal sulphur content determining on the base of the data about sensitivity to sulphur and effecting factors using ultimate methods of coal components substitution methods allowing to optimize sulphur control parameters; there has been worked out an algorithm of X-ray-radiometric control of sulphur content based on the sequential radiating the analyzed coal with gamma-radiation of

Sulphur isotope variations in the atmosphere

International Nuclear Information System (INIS)

Newman, L.; Krouse, H.R.; Grinenko, V.A.

1991-01-01

The measurement of the isotope ratios of sulphur and oxygen can in principal be used to assess sulphur inputs into, transformation within, and removal from the atmosphere. Major inputs arise from both anthropogenic and biogenic activities. Transformations arise from oxidation, neutralization, and other chemical reactions. Advection causes dilution and the main removal processes are dry deposition (governed by gravitation and diffusion) and rain. The admixture of sources can be discerned from their isotopic signatures whereas transformations and removal can be followed from the isotopic fractionation that might occur. In this chapter, the atmospheric sulphur cycle and the associated chemistry are summarized. Also presented is information on natural isotopic variations and fundamental concepts relating to the use of isotopic data to delineate anthropogenic S in the atmosphere. Examples of successful applications of these concepts are given. Finally, consideration is given to the potential of using isotopically enriched sulphur to study transport and transformation of atmospheric S compounds. Refs, figs and tabs

Sulphur recirculation for reduced boiler corrosion; Minskad pannkorrosion med svavelrecirkulation

Energy Technology Data Exchange (ETDEWEB)

Andersson, Sven; Karlsson, Martin (Goetaverken Miljoe AB, Goeteborg (Sweden)); Blomqvist, Evalena; Baefver, Linda; Claesson, Frida; Davidsson, Kent (SP Sveriges Tekniska Forskningsinstitut, Boraas (Sweden)); Froitzheim, Jan; Pettersson, Jesper; Steenari, Britt-Marie (Chalmers Tekniska Hoegskola, Oorganisk miljoekemi, Goeteborg (Sweden))

2010-03-15

Sulphur recirculation is a new technology for reducing boiler corrosion and dioxin formation, which was demonstrated in full-scale tests performed at the Renova Waste to Energy plant at Saevenaes in Goeteborg (Sweden). Sulphur is recirculated from the flue gas cleaning back to the boiler, which reduces the chloride content of the deposits, which in turn reduces boiler corrosion and dioxin formation. Sulphur dioxide was separated from the flue gas in a wet scrubber by adding hydrogen peroxide, producing sulphuric acid. The sulphuric acid was injected into the furnace using nozzles with atomization air, surrounded by recirculated flue gas for improved mixing. By recirculating the sulphur, the sulphur dioxide concentration was increased in the boiler. Each sulphur atom passed the boiler several times and no external sulphur had to be added. Dioxin, ash, deposits and particle samplings together with 1000 h corrosion probe measurements were performed for normal operation (reference) and with sulphur recirculation respectively. During spring 2009, reference measurements were made and the recirculation system was installed and tested. During autumn 2009, a long term test with sulphur recirculation was made. An SO{sub 2} concentration of approximately 800 mg/m3 (n, d.g.) was maintained in the boiler by the system except during a period of extremely low sulphur content in the waste. The sulphur dioxide stack concentrations have been far below the emission limit. Sulphuric acid dew point measurements have shown that the sulphuric acid dosage did not lead to elevated SO{sub 3} concentrations, which may otherwise lead to low temperature corrosion. The chlorine content of both fly ash and boiler ash decreased and the sulphur content increased during the sulphur recirculation tests. The molar chlorine/sulphur ratio (Cl/S) decreased by two thirds in the fly ash as well as in the boiler ash, except for one sample. With sulphur recirculation in operation, the deposit growth was

Biodesulphurisation of high sulphur coal by heap leaching

Energy Technology Data Exchange (ETDEWEB)

J. Cara; M.T. Carballo; A. Moran; D. Bonilla; O. Escolano; F.J. Garcia Frutos [Universidad de Leon, Leon (Spain). Departamento de Ingenieria Quimica

2005-10-01

The biodesulphurisation of coal carried out in pile could be an interesting option to clean coal. In view of the good results obtained in biodesulphurisation test column at lab scale on a sample of semianthracite coal that proceed of an industrial plant with a high sulphur content, mainly pyritic sulphur, the feasibility of the process at pilot plant scale was studied. The pile was formed with 6 ton of gravity middlings coal sample with a grain size -12+0.5 mm from S.A. Hullera Vasco-Leonesa industrial plant. The coal has a total sulphur content of 3.78% and a pyritic sulphur content of 2.88%, the rest of sulphur is organic sulphur. The biodesulphurisation process in pilot plant follows three stages: stabilization of the pile, biodesulphurisation and washing. Heap was sampled twice during stabilisation stage, at the end of desulphurisation process and finally once washed. A pyritic sulphur removal of 39% and total sulphur removal of 23% was obtained. To complete the bioleaching process, the treatment of purge of leachate was carried out with the objective to recycling to head of process. The best treatment was a pre-treatment of the leachate until pH 4, and further treatment by reverse osmosis of the clarified water. Comparing this process with conventional precipitation to reach disposal limits, the reagents consumption and sludges were reduced considerably and due to the high quality of permeate it permits to recycle it to head of process. 18 refs., 6 figs., 6 tabs.

Potential to reduce emissions of sulphur dioxide through reducing sulphur levels in heavy and light fuel oils - a discussion paper

International Nuclear Information System (INIS)

Tushingham, M.; Bellamy, J.

2001-01-01

Background information on the sulphur levels in light fuel oil (used in residential heating) and heavy fuel oil (used as industrial fuel oil) is provided. In addition to the description of sulphur levels in light and heavy fuel oils, the report also provides a summary of regulatory limits in Canada and elsewhere, and a description of the emission benefits of decreasing sulphur in fuels. 4 refs., 10 tabs., 12 figs

Source of sulphur in the Ebro Basin (Northern Spain). Tertiary nonmarine evaporite deposits as evidenced by sulphur isotopes

International Nuclear Information System (INIS)

Birnbaum, S.J.; Coleman, D.

1979-01-01

The Ebro Basin is an intermontane basin, located in northern Spain, filled with Tertiary (largely Oligocene and Miocene) elastic and chemical deposits. Sulphur isotopes are utilized to determine the source of sulphur in the sulphate deposits (predominantly gypsum with accessory thenardite, mirabolite and epsomite). Data obtained from Tertiary gypsum rocks produce a range of delta 34 S values from +9.16% to + 14.02% with a mean of +13.61%. Data obtained from Triassic gypsum rocks (in source area) produce a range from +13.73% to +15.14%, with a mean of +14.66%. Values for Tertiary marine water range from +18% to +24%. These data indicate a nonmarine origin for sulpur within the Tertiary sulphate rocks. The contribution of Triassic sulphur to the groundwater system, plus varying degrees of dilution by isotopically lighter (atmospheric and sulphide) sulphur, best explains the isotopic ratios observed in the Tertiary Basin deposits. (Auth.)

Nornahraun lava morphology and mode of emplacement

Science.gov (United States)

Pedersen, Gro B. M.; Höskuldsson, Armann; Riishuus, Morten S.; Jónsdóttir, Ingibjörg; Gudmundsson, Magnús T.; Sigmundsson, Freysteinn; Óskarsson, Birgir V.; Drouin, Vincent; Gallagher, Catherine; Askew, Rob; Moreland, William M.; Dürig, Tobias; Dumont, Stephanie; Þórdarson, Þór

2015-04-01

The ongoing Nornahraun eruption is the largest effusive eruption in Iceland since the Laki eruption in 1783-84, with an estimated lava volume of ~1.15 km3 covering an area of ~83.4 km2 (as of 5 JAN 2015). The eruption provides an unprecedented opportunity to study i) lava morphologies and their emplacement styles, ii) the transition from from open to closed lava pathways and iii) lava pond formation. Tracking of the lava advancement and morphology has been performed by GPS and GoPro cameras installed in 4×4 vehicles as well as video footage. Complimentary observations have been provided from aircraft platforms and by satellite data. Of particular importance for lava morphology observations are 1-12 m/pixel airborne SAR images (x-band). The Nornahraun flow field comprises a continuum of morphologies from pāhoehoe to 'a'ā, which have varied tem-porally and spatially. At the onset of the eruption 31 AUG, lava flows advanced rapidly (400-800 m/hr) from the 1.5 km long fissure as large slabby pāhoehoe [1-3] sheet lobes, 100-500 m wide and 0.3-1 m thick at the flow fronts. By 1 SEPT, the flows began channeling towards the NE constrained by the older Holuhraun I lava field and the to-pography of flood plain itself. A central open channel developed, feeding a 1-2 km wide active 'a'ā frontal lobe that advanced 1-2 km/day. In addition to its own caterpillar motion, the frontal lobe advanced in a series of 30-50 m long breakouts, predominantly slabby and rubbly pāhoehoe [4,5]. These breakouts had initial velocities of 10-30 m/hr and reached their full length within tens of minutes and subsequently inflated over hours. With the continuous advancement of the 'a'ā flow front, the breakouts were incorporated into the 'a'ā flow fronts and seldom preserved. At the margins of the frontal lava lobe, the breakouts were more sporadic, but predominantly rubbly pāhoehoe and slabby pāhoehoe, as at the flow front. The lava flow advanced ENE into Jökulsá á Fjöllum on 7 SEPT

Development of the floating sulphur biofilm reactor for sulphide ...

African Journals Online (AJOL)

Development of the floating sulphur biofilm reactor for sulphide oxidation in biological water treatment systems. ... The effect of influent sulphide concentrations, flow rate and reactor dimensions on the sulphur biofilm formation were investigated for the optimisation of elemental sulphur recovery and sulphide removal ...

Flood discharges and hydraulics near the mouths of Wolf Creek, Craig Branch, Manns Creek, Dunloup Creek, and Mill Creek in the New River Gorge National River, West Virginia

Science.gov (United States)

Wiley, J.B.

1994-01-01

The U.S. Geological Survey, in cooperation with the National Park Service, studied the frequency and magnitude of flooding near the mouths of five tributaries to the New River in the New River Gorge National River. The 100-year peak discharge at each tributary was determined from regional frequency equations. The 100-year discharge at Wolf Creek, Craig Branch, Manns Creek, Dunloup Creek, and Mill Creek was 3,400 cubic feet per second, 640 cubic feet per second, 8,200 cubic feet per second, 7,100 cubic feet per second, and 9,400 cubic feet per second, respectively. Flood elevations for each tributary were determined by application of a steady-state, one-dimensional flow model. Manning's roughness coefficients for the stream channels ranged from 0.040 to 0.100. Bridges that would be unable to contain the 100-year flood within the bridge opening included: the State Highway 82 bridge on Wolf Creek, the second Fayette County Highway 25 bridge upstream from the confluence with New River on Dunloup Creek, and an abandoned log bridge on Mill Creek.

How sulphur was dislodged to sustain plant operation

International Nuclear Information System (INIS)

Verma, A.N.; Agarwal, A.K.

1997-01-01

Heavy Water Plant (Kota) employs chemical exchange between water and hydrogen sulphide gas. Formation of sulphur is a known phenomena during production of heavy water in G.S. process plants. It is observed that after three years of plant operation this sulphur is enough to choke the cold tower trays causing flooding of exchange towers and resultant decrease in throughput. G.S. process plants normally go for major turn around once in four years when sulphur is either manually cleaned or removed by steam wash after hydrogen sulphide gas has been removed from the system and towers have been fully decontaminated. As throughput starts decreasing after third year and plant operation becomes more difficult in fourth year, HWP (Kota) had evolved a procedure of heating the towers for dislodging sulphur from sieve trays when plant is running. With these procedures plant operation could be sustained without tower floodings even in fourth year, before plant could go for major turn around for manual removal of sulphur

Lava Flow at Kilauea, Hawaii

Science.gov (United States)

2007-01-01

On July 21, 2007, the world's most active volcano, Kilauea on Hawaii's Big Island, produced a new fissure eruption from the Pu'u O'o vent, which fed an open lava channel and lava flows toward the east. Access to the Kahauale'a Natural Area Reserve was closed due to fire and gas hazards. The two Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) nighttime thermal infrared images were acquired on August 21 and August 30, 2007. The brightest areas are the hottest lava flows from the recent fissure eruption. The large lava field extending down to the ocean is part of the Kupaianaha field. The most recent activity there ceased on June 20, but the lava is still hot and appears bright on the images. Magenta areas are cold lava flows from eruptions that occurred between 1969 and 2006. Clouds are cold (black) and the ocean is a uniform warm temperature, and light gray in color. These images are being used by volcanologists at the U.S. Geological Survey Hawaii Volcano Observatory to help monitor the progress of the lava flows. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet. ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra spacecraft. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties

Organic sulphur in macromolecular sedimentary organic matter. II. Analysis of distributions of sulphur-containing pyrolysis products using multivariate techniques

NARCIS (Netherlands)

Sinninghe Damsté, J.S.; Eglinton, T.I.; Pool, W.; Leeuw, J.W. de; Eijkel, G.; Boon, J.J.

1992-01-01

This study describes the analysis of sulphur-containing products from Curie-point pyrolysis (Py) of eighty-five samples (kerogens, bitumen, and petroleum asphaltenes and coals) using gas chromatography (GC) in combination with sulphur-selective detection. Peak areas of approximately forty individual

Using Lava Tube Skylight Thermal Emission Spectra to Determine Lava Composition on Io: Quantitative Constraints for Observations by Future Missions to the Jovian System.

Science.gov (United States)

Davies, A. G.

2008-12-01

Deriving the composition of Io's dominant lavas (mafic or ultramafic?) is a major objective of the next missions to the jovian system. The best opportunities for making this determination are from observations of thermal emission from skylights, holes in the roof of a lava tube through which incandescent lava radiates, and Io thermal outbursts, where lava fountaining is taking place [1]. Allowing for lava cooling across the skylight, the expected thermal emission spectra from skylights of different sizes have been calculated for laminar and turbulent tube flow and for mafic and ultramafic composition lavas. The difference between the resulting mafic and ultramafic lava spectra has been quantified, as has the instrument sensitivity needed to acquire the necessary data to determine lava eruption temperature, both from Europa orbit and during an Io flyby. A skylight is an excellent target to observe lava that has cooled very little since eruption (California Institute of Technology, under contract to NASA. AGD is supported by a grant from the NASA OPR Program. References: [1] Davies, A. G., 1996, Icarus, 124, 45-61. [2] Keszthelyi, L., et al., 2006, JGS, 163, 253-264. [3] Davies, A. G., 2007, Volcanism on Io, Cambridge University Press. [4] Keszthelyi, L., et al., 2007, Icarus, 192, 491-502. [5] Davies, A. G., et al., 2006, Icarus, 184, 460-477.

Development of a Linear Flow Channel Reactor for sulphur removal ...

African Journals Online (AJOL)

2013-09-23

Sep 23, 2013 ... gation of sulphur production in floating sulphur biofilms as a means for addressing this problem. These 50 µm ... Preliminary studies on the use of the FSB system for sulphur removal in Integrated Managed Passive Treatment ...

Possible lava tube system in a hummocky lava flow at Daund ...

Indian Academy of Sciences (India)

R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

The presence of a branching and meandering lava tube system in the Daund flow, which represents the ..... is entirely related to the process of differential ero- sion and exhumation. Thus ... illuminating and thought provoking. References.

Vegetation - Pine Creek WA and Fitzhugh Creek WA [ds484

Data.gov (United States)

California Natural Resource Agency — This fine-scale vegetation classification and map of the Pine Creek and Fitzhugh Creek Wildlife Areas, Modoc County, California was created following FGDC and...

Distribution of sulphur into products from waste tire pyrolysis

International Nuclear Information System (INIS)

Susa, D.; Haydary, J.; Markos, J.

2012-01-01

Tire pyrolysis is getting growing attention as an effective waste tire disposal method in comparison to environmentally less friendly methods like dumping or incineration. But the scrap tire sulphur content can be a potential obstacle to scrap tire utilization as a fuel. In this paper the distribution of sulphur into tire pyrolysis yields, solid (char) and liquid (tar), was investigated. The pyrolysis experiments were carried out under different conditions to determine the partitioning of sulphur into pyrolysis products. The influence of different temperatures and reaction times was investigated in a laboratory flow reactor under nitrogen atmosphere. Solid and liquid residues were collected and analyzed by elemental analysis. The sulphur content in residual char and tar was determined using an elemental analyzer and the sulphur forms in tar were characterized by the X-ray photoelectron spectroscopy (XPS). (Authors)

Optimal sulphuric acid production using Acidithiobacillus caldus ...

African Journals Online (AJOL)

AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING ... oxygen uptake rate of 1.35 g/L.day (OUR), 52% sulphur conversion at a rate of 0.83 ... achieving a sulphuric acid production rate of 2.76 g/L.day (dP/dt), while the ...

LiDAR-derived surface roughness signatures of basaltic lava types at the Muliwai a Pele Lava Channel, Mauna Ulu, Hawai`i

Science.gov (United States)

Whelley, Patrick L.; Garry, W. Brent; Hamilton, Christopher W.; Bleacher, Jacob E.

2017-11-01

We used light detection and ranging (LiDAR) data to calculate roughness patterns (homogeneity, mean-roughness, and entropy) for five lava types at two different resolutions (1.5 and 0.1 m/pixel). We found that end-member types (´áā and pāhoehoe) are separable (with 95% confidence) at both scales, indicating that roughness patterns are well suited for analyzing types of lava. Intermediate lavas were also explored, and we found that slabby-pāhoehoe is separable from the other end-members using 1.5 m/pixel data, but not in the 0.1 m/pixel analysis. This suggests that the conversion from pāhoehoe to slabby-pāhoehoe is a meter-scale process, and the finer roughness characteristics of pāhoehoe, such as ropes and toes, are not significantly affected. Furthermore, we introduce the ratio ENT/HOM (derived from lava roughness) as a proxy for assessing local lava flow rate from topographic data. High entropy and low homogeneity regions correlate with high flow rate while low entropy and high homogeneity regions correlate with low flow rate. We suggest that this relationship is not directional, rather it is apparent through roughness differences of the associated lava type emplaced at the high and low rates, respectively.

LiDAR-Derived Surface Roughness Signatures of Basaltic Lava Types at the Muliwai a Pele Lava Channel, Mauna Ulu, Hawai'i

Science.gov (United States)

Whelley, Patrick L.; Garry, W. Brent; Hamilton, Christopher W.; Bleacher, Jacob E.

2017-01-01

We used light detection and ranging (LiDAR) data to calculate roughness patterns (homogeneity, mean-roughness, and entropy) for five lava types at two different resolutions (1.5 and 0.1 m/pixel). We found that end-member types (a a and pahoehoe) are separable (with 95% confidence) at both scales, indicating that roughness patterns are well suited for analyzing types of lava. Intermediate lavas were also explored, and we found that slabby-pahoehoe is separable from the other end-members using 1.5 m/pixel data, but not in the 0.1 m/pixel analysis. This suggests that the conversion from pahoehoe to slabby-pahoehoe is a meter-scale process, and the finer roughness characteristics of pahoehoe, such as ropes and toes, are not significantly affected. Furthermore, we introduce the ratio ENT/HOM (derived from lava roughness) as a proxy for assessing local lava flow rate from topographic data. High entropy and low homogeneity regions correlate with high flow rate while low entropy and high homogeneity regions correlate with low flow rate.We suggest that this relationship is not directional, rather it is apparent through roughness differences of the associated lava type emplaced at the high and low rates, respectively.

Diverting lava flows in the lab

Science.gov (United States)

Dietterich, Hannah; Cashman, Katharine V.; Rust, Alison C.; Lev, Einat

2015-01-01

Recent volcanic eruptions in Hawai'i, Iceland and Cape Verde highlight the challenges of mitigating hazards when lava flows threaten infrastructure. Diversion barriers are the most common form of intervention, but historical attempts to divert lava flows have met with mixed success and there has been little systematic analysis of optimal barrier design. We examine the interaction of viscous flows of syrup and molten basalt with barriers in the laboratory. We find that flows thicken immediately upslope of an obstacle, forming a localized bow wave that can overtop barriers. Larger bow waves are generated by faster flows and by obstacles oriented at a high angle to the flow direction. The geometry of barriers also influences flow behaviour. Barriers designed to split or dam flows will slow flow advance, but cause the flow to widen, whereas oblique barriers can effectively divert flows, but may also accelerate flow advance. We argue that to be successful, mitigation of lava-flow hazards must incorporate the dynamics of lava flow–obstacle interactions into barrier design. The same generalizations apply to the effect of natural topographic features on flow geometry and advance rates.

Discontinuities in Jovian sulphur plasma

Energy Technology Data Exchange (ETDEWEB)

Mekler, Y [Jet Propulsion Lab., Pasadena, CA (USA); Eviatar, A; Siscoe, G L

1979-10-01

In recent years, the Jovian sulphur nebula, which is the only component of the thermal plasma in the magnetosphere of Jupiter which emits in the visible, has been the subject of considerable study. A large number of investigators have come up with widely differing models for the density, composition and temperature of the Jovian magnetospheric plasma. In this paper a different characteristic of the sulphur emission, namely its radial distribution is discussed and an attempt is made to assess its implications for the plasma and magnetic field configuration of the inner magnetosphere of Jupiter.

Water quality study at the Congaree Swamp National monument of Myers Creek, Reeves Creek and Toms Creek. Technical report

International Nuclear Information System (INIS)

Rikard, M.

1991-11-01

The Congaree Swamp National Monument is one of the last significant near virgin tracts of bottom land hardwood forests in the Southeast United States. The study documents a water quality monitoring program on Myers Creek, Reeves Creek and Toms Creek. Basic water quality parameters were analyzed. High levels of aluminum and iron were found, and recommendations were made for further monitoring

Unravelling the sulphur isotope systematics of an alkaline magmatic province: implications for REE mineralization and exploration

Science.gov (United States)

Hutchison, W.; Finch, A.; Boyce, A.; Friis, H.; Borst, A. M.; Horsburgh, N. J.

2017-12-01

Some of the world's best alkaline rare earth element (REE) deposits are formed in magmatic systems that are sealed (i.e., those that are autometasomatised and maintain reducing conditions). Conversely, in open systems where oxidizing fluids infiltrate, it is commonly assumed that REE are redistributed over a wider (less concentrated) zone. Sulphur isotope fractionation is sensitive to variations in temperature and redox, and, although sulphide minerals are relatively abundant in alkaline systems, there have been few attempts to test these hypotheses and develop a sulphur isotope proxy for alkaline metasomatism and formation of associated REE deposits. The Gardar Rift Province in southern Greenland was volcanically active in two periods between 1300 and 1100 Ma and is an ideal natural laboratory to explore sulphur isotope systematics because a near-complete alkaline magmatic lineage is exposed. We present new δ34S from across the province with a particular focus on three alkaline systems (Ilímaussaq, Motzfeldt and Ivigtût) that also host major REE deposits. Primitive mafic rocks from regional Gardar dykes and lavas have a restricted range of δ34S between 0 and 3 ‰ and fractional crystallization imparts no observable change in δ34S. In a few cases high-δ34S rocks (>15 ‰) occur when intrusive units have assimilated local sedimentary crust (δ34S = 25 ‰). Most δ34S variation takes place in the roof zones of alkaline intrusions during late-magmatic and hydrothermal stages, and we identify clear differences between the complexes. At Ilímaussaq, where the magmatic series is exceptionally reduced (below QFM buffer), roof zone δ34S remains narrow (0-3 ‰). At Motzfeldt, a more open oxidizing roof zone (MH buffer), δ34S ranges from -12 ‰ in late-stage fluorite veins to +12 ‰ where local crust has been assimilated. Ivigtût is intermediate between these end-members varying between -5 to +5 ‰. The δ34S variations primarily relate to temperature and

The Anatomy of the Blue Dragon: Changes in Lava Flow Morphology and Physical Properties Observed in an Open Channel Lava Flow as a Planetary Analogue

Science.gov (United States)

Sehlke, A.; Kobs-Nawotniak, S. E.; Hughes, S. S.; Sears, D. W. G.; Downs, M.; Whittington, A. G.; Lim, D. S. S.; Heldmann, J. L.

2017-12-01

Lava terrains on other planets and moons exhibit morphologies similar to those found on Earth, such as smooth pāhoehoe transitioning to rough `a`ā terrains based on the viscosity - strain rate relationship of the lava. Therefore, the morphology of lava flows is governed by eruptive conditions such as effusion rate, underlying slope, and the fundamental thermo-physical properties of the lava, including temperature (T), composition (X), viscosity (η), fraction of crystals (φc) and vesicles (φb), as well as bulk density (ρ). These textural and rheological changes were previously studied for Hawaiian lava, where the lava flow started as channelized pāhoehoe and transitioned into `a`ā, demonstrating a systematic trend in T, X, η, φc, φb, and ρ. NASA's FINESSE focuses on Science and Exploration through analogue research. One of the field sites is Craters of the Moon, Idaho. We present field work done at a 3.0 km long lava flow belonging to the Blue Dragon lavas erupted from a chain of spatter cones, which then coalesced into channelized flows. We acquired UAV imagery along the entire length of the flow, and generated a high resolution DTM of 5 cm/pixel, from which we derived height profiles and surface roughness values. Field work included mapping the change in surface morphology and sample collection every 150 meters. In the laboratory, we measured φc, φb, and ρ for all collected samples. Viscosity measurements were carried out by concentric cylinder viscometry at subliquidus temperatures between 1310ºC to 1160ºC to study the rheology of the lava, enabling us to relate changes in flow behavior to T and φc. Our results are consistent with observations made for Hawaiian lava, including increasing bulk density downflow, and porosity changing from connected to isolated pore space. Crystallinity increases downflow, and the transition from pāhoehoe to `a`ā occurs between 1230ºC to 1150ºC, which is prompted by nucleation and growth of plagioclase

Sulphur self–retention and sulphur dioxide capture with active calcium minerals in mineral–rich coals / Mchabe, D.

OpenAIRE

Mchabe, Dursman

2011-01-01

In order to provide information for the development of clean coal technology, the sulphur self–retention and sulphur dioxide capturing properties of minerals present in low grade coals was investigated. This study consisted of detailed mineral analyses of coal and ash samples using results obtained from QEMSCAN and separate retention (coal) and capture (ash) experiments with laboratory scale reactors. Typical South African coal samples were used in this study. The ash content v...

Muon transfer to sulphur dioxide

International Nuclear Information System (INIS)

Mulhauser, F.; Schneuwly, H.

1993-01-01

A systematic study of muon capture and muon transfer has been performed in seven different H 2 + SO 2 gas mixtures. From the single-exponential time structure of the muonic sulphur x-rays, one determines the lifetime of the μp atoms under the given experimental conditions. The reduced muon transfer rates to the sulphur dioxide molecule, deduced from these lifetimes, all agree well with each other. The muonic oxygen time spectra show an additional structure as if μp atoms of another kind were present. Comparable time structures are observed in a D 2 + SO 2 mixture. (author)

Stratigraphy of the Kapalga Formation north of Pine Creek and its relationship to base metal mineralization

International Nuclear Information System (INIS)

Goulevitch, J.

1980-01-01

The lithology, stratigraphy and mineralization of the Kapalga Formation (South Alligator Group) is described from the Margaret Syncline in the Pine Creek area of the Northern Territory of Australia. An interdigitation of carbonaceous siltstones and mudstones, chert, ashstones and tuffaceous chert, greywacke, siltstone, mudstone and minor banded iron formation (b.i.f.) characterises the Formation. These rocks define a vertical facies transition between low energy sediments of the underlying Koolpin Formation, and high energy sediments of the overlying Burrell Creek Formation. This transition is interlayered with numerous ashstone-tuffaceous chert horizons which were deposited during the waning stage of Gerowie Tuff sedimentation. The boundary between the Kapalga Formation of the South Alligator Group and the Burrell Creek Formation of the Finniss River Group is strictly conformable in this part of the Pine Creek 'Geosyncline'. Relict devitrified shards have been recognised in the Gerowie Tuff in the Margaret Syncline and these observations along with whole-rock chemical analyses conclusively support claims by previous investigators that these rocks are volcanic derivatives. Base metal mineralization at Iron Blow and Mt. Bonnie occurs as massive, stratiform, sulphide-silicate-carbonate lodes. The deposits are at the same stratigraphic level towards the base of the Kapalga Formation and minor stratification parallel with bedding has been observed. These features, and the association of the lodes with mud-flow breccias, lead to the conclusion that the lodes are syngenetic in origin. Thermochemical consideration of the sulphide assemblages together with the temporal relationship between the mineralization and Gerowie Tuff point to diagenetic devitrification of the underlying tuffaceous rocks as the source of the mineralization. Recent publications of experimental data from reaction of seawater and volcanic glass provide information which supports this thesis, and

Sulphate sulphur concentration in vegetable crops, soil and ground water in the region affected by the sulphur dioxide emission from Plock oil refinery (central Poland)

International Nuclear Information System (INIS)

Mikula, W.

1995-01-01

Research was carried out in 1984-1990 in the region affected by the sulphur dioxide emission from one of the greatest oil refineries in Europe (Plock, central Poland). The sulphate sulphur concentration in the vegetable crops (red beet, carrot, parsley, bean, cabbage and dill), the soil and in ground water was defined in selected allotment gardens of Plock city and in a household garden located in the rural area about 25 km from the town. The highest amount of sulphur was found in the vegetable crops cultivated in the garden situated in the closest vicinity of the refinery. Sulphate sulphur contents harmful for plants (above 0.50 per cent d.m.) were noted in cabbage and carrot leaves in almost all the gardens (except one). The soil in all examined gardens was characterised by high sulphate sulphur concentration, which considerably exceeds the maximum amount admissible for light soil in Poland, i.e. 0.004 per cent d.m. The sulphate sulphur concentration in ground water in all the gardens exceeded the highest permissible content in drinking water in Poland. The sulphate sulphur content in the soil and ground water was not significantly dependent on the garden's distance from the refinery. Generally, the above normal sulphate sulphur concentrations occurred quite universally in the examined region and they concerned all the considered environmental components (vegetable crops, soil, ground water) and all the gardens. 22 refs., 6 tabs

Availability and uptake of sulphur by mustard in three soils in Udaipur valley

International Nuclear Information System (INIS)

Kataria, S.K.; Shriniwas

1976-01-01

The differential behaviour of three soils (Bargaon, Bhatewar red and Bhatewar black) for availability of sulphur to mustard was studied in a greenhouse pot culture experiment using five doses of sulphur (0,20,40,80,120 ppm) applied as 35 S tagged ammonium sulphate. Application of sulphur significantly increased the dry matter of mustard over control, however, maximum dry matter was obtained when sulphur was applied at 40 ppm level, thereafter, any higher doses did not prove beneficial. Sulphur content in the plant tissue and percent of sulphur in the plant derived from fertilizer increased with successive doses of applied sulphur. (author)

Effect of sulphur on the strengthening of a Zr-Nb alloy

International Nuclear Information System (INIS)

Chang, K.I.; Hong, S.I.

2008-01-01

The effect of sulphur on the strengthening and the thermally activated deformation of cold-worked Zr-1 Nb alloy was investigated. In the present study, the sulphur strengthening was observed even at room temperature unlike the previous study of Ferrer et al. The flow stress increased by 65 MPa at room temperature with the addition of sulphur as little as 20 ppm. With further increase of sulphur content up to 300 ppm, negligible change of the flow stress was observed. The additive strengthening behavior in which the entire stress-strain curve shift upward by the friction stress due to the addition of sulphur was observed in the Zr-Nb alloy of the present study. The activation volume decreased slightly (from 110b 3 to 80b 3 ) with the addition of 300 ppm sulphur at room temperature. The rate-controlling mechanism of the deformation can best be explained by the dislocation interaction mechanism in which the segregation of alloying elements such as oxygen and sulphur atoms affects the activation length of dislocations

Characteristics and genesis of porphyroclastic lava rock in Xiangshan

International Nuclear Information System (INIS)

Zhou Xiaohua; Wang Zhuning

2012-01-01

Due to the transitional characteristics of porphyroclastic lava rock in Xiangshan of Jiangxi province, there are a variety of views on its genesis, petrographic attribution. This is because the marginal facies of the porphyroclastic lava is with ignimbrite and tuff characteristics, its transition phase has the characteristics of lava, and its intermediate phase has the feature of sub-volcanic rocks, further more, different texture of the rocks bears transition relationship. By the study of mineral composition, REE pattern, trace elements, isotopes, we put forward that the porphyroclastic lava is formed by the remelting of basement metamorphic rocks. The rocks was believed to be formed in the environment similar to volcanics and subvolcanics, and quite different to plutonic rocks due to the features of low-structure of potassium feldspar phenocrysts and solution mechanism, because the porphyroclastic lava phenocrysts occurs as fragments and maybe related to cryptoexplosion. Therefore the rocks was believed to belong to the volcano extrusive facies. (authors)

Organically bound sulphur in coal: A molecular approach

NARCIS (Netherlands)

Sinninghe Damsté, J.S.; Leeuw, J.W. de

1992-01-01

A critical review of literature concerning the molecular characterization of low and high molecular weight organosulphur constitutents present in coal as well as a detailed analysis of organic sulphur compounds present in flash evaporates and pyrolysates of a suite of coals ranging in sulphur

Terraced margins of inflated lava flows on Earth and Mars

Science.gov (United States)

Zimbelman, J. R.; Garry, W. B.; Bleacher, J. E.; Crumpler, L. S.

2011-12-01

When fluid basaltic lava flows are emplaced over a shallow regional slope (typically much less than one degree), the lava flows often display impressive characteristics of inflation. Here we describe a distinctive marginal characteristic that is often developed along the margins of endogenously inflated basaltic lava flows; discreet topographic levels of the emplaced lava that are here termed 'terraced margins'. Terraced margins were first noted at the distal end of the Carrizozo lava flow in central New Mexico, where they are particularly well expressed, but terraces have also been observed along some margins of the McCartys lava flow (NM), the distal end of the 1859 Mauna Loa lava flow (HI), and lava flows at Craters of the Moon (ID). Differential Global Positioning System surveys across several terraced margins reveal consistent topographic characteristics: the upper surface of each terrace level is at roughly one half the height of the sheet lobe from which it emerges; when a terrace becomes the source of an additional outbreak, the upper surface of the second terrace is at roughly one half the height of the source terrace; often a subtle topographic depression is present along the contact between a terrace and its source sheet lobe, suggesting that the terrace outflow starts at a level roughly one-third the height of the source lobe; the upper surfaces of both the source sheet lobe and associated terraces are level to within tens of centimeters across length scales of many tens to hundreds of meters, indicative of inflation of all components. The field observations will be used as the constraints for modeling of the inflation and terracing mechanisms, an effort that has only recently started. The multiple imaging data sets now available for Mars have revealed the presence of terraced margins on some lava flows on Mars. Although detailed topographic data are not currently available for the Martian examples identified so far, the presence of terraced margins for

Observations of obsidian lava flow emplacement at Puyehue-Cordón Caulle, Chile

Science.gov (United States)

Tuffen, H.; Castro, J. M.; Schipper, C. I.; James, M. R.

2012-04-01

The dynamics of obsidian lava flow emplacement remain poorly understood as active obsidian lavas are seldom seen. In contrast with well-documented basaltic lavas, we lack observational data on obsidian flow advance and temporal evolution. The ongoing silicic eruption at Puyehue-Cordón Caulle volcanic complex (PCCVC), southern Chile provides an unprecedented opportunity to witness and study obsidian lava on the move. The eruption, which started explosively on June 4th 2011, has since June 20 generated an active obsidian flow field that remains active at the time of writing (January 2012), with an area of ~6 km2, and estimated volume of ~0.18 km3. We report on observations, imaging and sampling of the north-western lava flow field on January 4th and 10th 2012, when vent activity was characterised by near-continuous ash venting and Vulcanian explosions (Schipper et al, this session) and was simultaneously feeding the advancing obsidian flow (Castro et al, this session). On January 4th the north-western lava flow front was characterised by two dominant facies: predominant rubbly lava approximately 30-40 m thick and mantled by unstable talus aprons, and smoother, thinner lobes of more continuous lava ~50 m in length that extended roughly perpendicular to the overall flow direction, forming lobes that protrude from the flow margin, and lacked talus aprons. The latter lava facies closely resembled squeeze-up structures in basaltic lava flows[1] and appeared to originate from and overlie the talus apron of the rubbly lava. Its upper surface consisted of smooth, gently folded lava domains cut by crevasse-like tension gashes. During ~2 hours of observation the squeeze-up lava lobe was the most frequent location of small-volume rockfalls, which occurred at ~1-10 minute intervals from the flow front and indicated a locus of lava advance. On January 10th the squeeze-up lava lobes had evolved significantly, with disruption and breakage of smooth continuous lava surfaces to form

Reactions of sulphur mustard on impregnated carbons.

Science.gov (United States)

Prasad, G K; Singh, Beer

2004-12-31

Activated carbon of surface area 1100 m2/gm is impregnated with 4% sodium hydroxide plus 3% Cr(VI) as CrO3 with and without 5% ethylene diamine (EDA), 4% magnesium nitrate and 5% ruthenium chloride by using their aqueous solutions. These carbons are characterized for surface area analysis by BET conventional method and exposed to the vapours of sulphur mustard (HD) at room temperature (30 degrees C). After 24 h, the reaction products are extracted in dichloromethane and analyzed using gas chromatography and mass spectrometry (GC-MS). Hemisulphur mustard, thiodiglycol, 1,4-oxathiane are observed to be the products of reaction between sulphur mustard and NaOH/CrO3/C system, whereas on NaOH/CrO3/EDA/C system HD reacted to give 1,4-thiazane. On Mg(NO3)2/C system it gave hemisulphur mustard and thiodiglycol. On RuCl3/C system it degraded to divinyl sulphone. Residual sulphur mustard is observed along with reaction products in all systems studied. Reaction mechanisms are also proposed for these interesting surface reactions. Above-mentioned carbons can be used in filtration systems for protection against hazardous gases such as sulphur mustard.

Reactions of sulphur mustard on impregnated carbons

International Nuclear Information System (INIS)

Prasad, G.K.; Singh, Beer

2004-01-01

Activated carbon of surface area 1100 m 2 /gm is impregnated with 4% sodium hydroxide plus 3% Cr(Vi) as CrO 3 with and without 5% ethylene diamine (EDA), 4% magnesium nitrate and 5% ruthenium chloride by using their aqueous solutions. These carbons are characterized for surface area analysis by BET conventional method and exposed to the vapours of sulphur mustard (HD) at room temperature (30 deg. C). After 24 h, the reaction products are extracted in dichloromethane and analyzed using gas chromatography and mass spectrometry (GC-MS). Hemisulphur mustard, thiodiglycol, 1,4-oxathiane are observed to be the products of reaction between sulphur mustard and NaOH/CrO 3 /C system, whereas on NaOH/CrO 3 /EDA/C system HD reacted to give 1,4-thiazane. On Mg(NO 3 ) 2 /C system it gave hemisulphur mustard and thiodiglycol. On RuCl 3 /C system it degraded to divinyl sulphone. Residual sulphur mustard is observed along with reaction products in all systems studied. Reaction mechanisms are also proposed for these interesting surface reactions. Above-mentioned carbons can be used in filtration systems for protection against hazardous gases such as sulphur mustard

Deformation at Lava Lake Volcanoes: Lessons from Karthala

Science.gov (United States)

Biggs, J.; Rust, A.; Owens, C.

2014-12-01

To remain hot, permanent lava lakes require a continuous connection to a magma reservoir. Depending on the state of the conduit, changes in magma pressure could result in changes in the lake level (hydraulic head) or be accommodated elastically leading to surface deformation. Observing deformation is therefore key to understanding the plumbing system associated with lava lakes. However, the majority of the world's lava lakes lie in difficult socio-economic or remote locations meaning that there are few ground-based observations, and it is often necessary to rely on satellite imagery. Karthala volcano experienced a sequence of eruptions in April 2005, Nov 2005, May 2006 and Jan 2007. The first 3 took place at the Choungou Chahale crater, which typically contains either a water or lava lake; the last formed a new pit crater to the north. Satellite thermal imagery (Hirn et al, 2008) does not show an anomaly during the first eruption, which had a phreatomagmatic component, but large thermal anomalies, associated with an ephemeral lava lake were detected during the Nov 2005 and May 2006 eruptions. The final eruption produced a smaller anomaly attributed to a minor lava flow. Here we present InSAR observations from 2004-2010. We find no significant deformation associated with the first three eruptions, but the January 2007 eruption was associated with ~25 cm of deformation near the volcano's summit, characteristic of a dyke intrusion aligned with the northern rift zone. We also observe an unusual pattern deformation along the coast which may be attributed to rapid settling of soft sediment or recent volcanic deposits triggered by seismic activity. We propose that the first eruption cleared the reservoir-summit connection and interacted with the water in Choungou Chahale. The following eruptions formed a lava lake, but without causing deformation. By the final eruption, the conduit had become blocked and magma intruded along the rift zone causing deformation but no

Hazard Monitoring of Growing Lava Flow Fields Using Seismic Tremor

Science.gov (United States)

Eibl, E. P. S.; Bean, C. J.; Jónsdottir, I.; Hoskuldsson, A.; Thordarson, T.; Coppola, D.; Witt, T.; Walter, T. R.

2017-12-01

An effusive eruption in 2014/15 created a 85 km2 large lava flow field in a remote location in the Icelandic highlands. The lava flows did not threaten any settlements or paved roads but they were nevertheless interdisciplinarily monitored in detail. Images from satellites and aircraft, ground based video monitoring, GPS and seismic recordings allowed the monitoring and reconstruction of a detailed time series of the growing lava flow field. While the use of satellite images and probabilistic modelling of lava flows are quite common tools to monitor the current and forecast the future growth direction, here we show that seismic recordings can be of use too. We installed a cluster of seismometers at 15 km from the vents and recorded the ground vibrations associated with the eruption. This seismic tremor was not only generated below the vents, but also at the edges of the growing lava flow field and indicated the parts of the lava flow field that were most actively growing. Whilst the time resolution is in the range of days for satellites, seismic stations easily sample continuously at 100 Hz and could therefore provide a much better resolution and estimate of the lava flow hazard in real-time.

Biological parameters in technogenic soils of a former sulphur mine

Science.gov (United States)

Siwik-Ziomek, Anetta; Brzezińska, Małgorzata; Lemanowicz, Joanna; Koper, Jan; Szarlip, Paweł

2018-04-01

This study was conducted on the soils originating from a reclamation area of the former sulphur mine in Tarnobrzeg, Poland. Soil was sampled 16 years after the completion of mining works with the open-pit method at Machów, as well as 7 years after sulphur mining via the `smelting' method in the Jeziórko mine was abandoned. Several biological parameters were examined: soil respiration, soil microbial biomass and the activity of rhodanese and arylsulphatase enzymes taking part in sulphur transformation within the site's soils. The soils showed a high total sulphur and sulphates content. The SO42- constituted a large fraction of total sulphur, in some cases, exceeding 80% or even 95% of total sulphur. The soil pH decreased due to the degrading effects of sulphur mining. In the soils studied from the locations with the lowest soil pH value, no activity of arylsulphatase was reported and the activity of rhodanese was lowest. The highest soil respiration values were recorded from the 0-5 cm layer in the areas covered with forest vegetation. A high soil respiration value at the waste heap at Machów wherein a very high concentration of Stot and SO42- was observed can be due to the ability of fungi to produce hyphal strands and to survive unfavourable conditions.

A new technology aimed at re-establishing a global sulphur supply/demand balance

International Nuclear Information System (INIS)

Slavens, A.F.; Jorgensen, C.; Ogg, D.

2009-01-01

The world's sulphur supply is mainly determined by involuntary production of elemental sulphur during the processing of oil and gas. As a result, sulphur supply is decoupled from demand, resulting in an imbalance between the two. For almost two decades, sulphur supply has exceeded demand, which has raised significant concerns for oil and gas producers such as where to store all of the excess sulphur, and how to transport a low-value commodity to market in an economically attractive fashion. Black and Veatch is involved in the development of a new technology called sulphur to energy process (STEP TM ) which has the potential to assist in balancing global sulphur supply and demand, as well as affording other benefits such as low-emission energy production. This paper presented the potential merits of the STEP as a means to reestablish a global sulphur supply/demand balance for the world trading market. It explored the other potential benefits that may result from the use of this new technology and compared STEP to other technologies and operating schemes that regulate sulphur supply. It was concluded that STEP has the potential to allow the processor to produce elemental sulphur when demand is high, or to provide safe and ecological disposal when demand is low, with the added benefits of energy recovery from the sulphur combustion process, and sour gas reservoir sweetening over time as sulphur dioxide reacts with hydrogen sulphide present in the reservoir. 13 refs., 3 tabs., 22 figs

Lava delta deformation as a proxy for submarine slope instability

Science.gov (United States)

Di Traglia, Federico; Nolesini, Teresa; Solari, Lorenzo; Ciampalini, Andrea; Frodella, William; Steri, Damiano; Allotta, Benedetto; Rindi, Andrea; Marini, Lorenzo; Monni, Niccolò; Galardi, Emanuele; Casagli, Nicola

2018-04-01

The instability of lava deltas is a recurrent phenomenon affecting volcanic islands, which can potentially cause secondary events such as littoral explosions (due to interactions between hot lava and seawater) and tsunamis. It has been shown that Interferometric Synthetic Aperture Radar (InSAR) is a powerful technique to forecast the collapse of newly emplaced lava deltas. This work goes further, demonstrating that the monitoring of lava deltas is a successful strategy by which to observe the long-term deformation of subaerial-submarine landslide systems on unstable volcanic flanks. In this paper, displacement measurements derived from Synthetic Aperture Radar (SAR) imagery were used to detect lava delta instability at Stromboli volcano (Italy). Recent flank eruptions (2002-2003, 2007 and 2014) affected the Sciara del Fuoco (SdF) depression, created a "stacked" lava delta, which overlies a pre-existing scar produced by a submarine-subaerial tsunamigenic landslide that occurred on 30 December 2002. Space-borne X-band COSMO-SkyMED (CSK) and C-band SENTINEL-1A (SNT) SAR data collected between February 2010 and October 2016 were processed using the SqueeSAR algorithm. The obtained ground displacement maps revealed the differential ground motion of the lava delta in both CSK and SNT datasets, identifying a stable area (characterized by less than 2 mm/y in both datasets) within the northern sector of the SdF and an unstable area (characterized by velocity fields on the order of 30 mm/y and 160 mm/y in the CSK and SNT datasets, respectively) in the central sector of the SdF. The slope stability of the offshore part of the SdF, as reconstructed based on a recently performed multibeam bathymetric survey, was evaluated using a 3D Limit Equilibrium Method (LEM). In all the simulations, Factor of Safety (F) values between 0.9 and 1.1 always characterized the submarine slope between the coastline and -250 m a.s.l. The critical surfaces for all the search volumes corresponded to

SULPHUR CONTAINING LICKS AND THEIR EFFECT ON THE ...

African Journals Online (AJOL)

amounts of sulphur, there are some of particular importance such as the vitamins thiamine and biotin. Sulphur is also ingested in the inorganic sulphide and sulphate forms, fractions of which are utilized in metabolic processes, whereas substantial portions are also excreted. It has been determined that thiol cornpounds.

The Chaitén rhyolite lava dome: Eruption sequence, lava dome volumes, rapid effusion rates and source of the rhyolite magma

Science.gov (United States)

Pallister, John S.; Diefenbach, Angela K.; Burton, William C.; Munoz, Jorge; Griswold, Julia P.; Lara, Luis E.; Lowenstern, Jacob B.; Valenzuela, Carolina E.

2013-01-01

We use geologic field mapping and sampling, photogrammetric analysis of oblique aerial photographs, and digital elevation models to document the 2008-2009 eruptive sequence at Chaitén Volcano and to estimate volumes and effusion rates for the lava dome. We also present geochemical and petrologic data that contribute to understanding the source of the rhyolite and its unusually rapid effusion rates. The eruption consisted of five major phases: 1. An explosive phase (1-11 May 2008); 2. A transitional phase (11-31 May 2008) in which low-altitude tephra columns and simultaneous lava extrusion took place; 3. An exogenous lava flow phase (June-September 2008); 4. A spine extrusion and endogenous growth phase (October 2008-February 2009); and 5. A mainly endogenous growth phase that began after the collapse of a prominent Peléean spine on 19 February 2009 and continued until the end of the eruption (late 2009 or possibly earliest 2010). The 2008-2009 rhyolite lava dome has a total volume of approximately 0.8 km3. The effusion rate averaged 66 m3s-1 during the first two weeks and averaged 45 m3s-1 for the first four months of the eruption, during which 0.5 km3 of rhyolite lava was erupted. These are among the highest rates measured world-wide for historical eruptions of silicic lava. Chaitén’s 2008-2009 lava is phenocryst-poor obsidian and microcrystalline rhyolite with 75.3±0.3% SiO2. The lava was erupted at relatively high temperature and is remarkably similar in composition and petrography to Chaitén’s pre-historic rhyolite. The rhyolite’s normative composition plots close to that of low pressure (100-200 MPa) minimum melts in the granite system, consistent with estimates of approximately 5 to 10 km source depths based on phase equilibria and geodetic studies. Calcic plagioclase, magnesian orthopyroxene and aluminous amphibole among the sparse phenocrysts suggest derivation of the rhyolite by melt extraction from a more mafic magmatic mush. High temperature

Sulphur-containing Amino Acids: Protective Role Against Free Radicals and Heavy Metals.

Science.gov (United States)

Colovic, Mirjana B; Vasic, Vesna M; Djuric, Dragan M; Krstic, Danijela Z

2018-01-30

Sulphur is an abundant element in biological systems, which plays an important role in processes essential for life as a constituent of proteins, vitamins and other crucial biomolecules. The major source of sulphur for humans is plants being able to use inorganic sulphur in the purpose of sulphur-containing amino acids synthesis. Sulphur-containing amino acids include methionine, cysteine, homocysteine, and taurine. Methionine and cysteine are classified as proteinogenic, canonic amino acids incorporated in protein structure. Sulphur amino acids are involved in the synthesis of intracellular antioxidants such as glutathione and N-acetyl cysteine. Moreover, naturally occurring sulphur-containing ligands are effective and safe detoxifying agents, often used in order to prevent toxic metal ions effects and their accumulation in human body. Literature search for peer-reviewed articles was performed using PubMed and Scopus databases, and utilizing appropriate keywords. This review is focused on sulphur-containing amino acids - methionine, cysteine, taurine, and their derivatives - glutathione and N-acetylcysteine, and their defense effects as antioxidant agents against free radicals. Additionally, the protective effects of sulphur-containing ligands against the toxic effects of heavy and transition metal ions, and their reactivation role towards the enzyme inhibition are described. Sulphur-containing amino acids represent a powerful part of cell antioxidant system. Thus, they are essential in the maintenance of normal cellular functions and health. In addition to their worthy antioxidant action, sulphur-containing amino acids may offer a chelating site for heavy metals. Accordingly, they may be supplemented during chelating therapy, providing beneficial effects in eliminating toxic metals. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Role of sulphur in rice production

International Nuclear Information System (INIS)

Sachdev, Pamila; Sachdev, M.S.

2002-01-01

Sulphur is an essential plant nutrient growing in international importance. Rice farmers usually apply nitrogen, phosphorus and potassium at high rates to the crop. Whenever there is an imbalance between off take and input of nutrients, it may lead to a decline in soil fertility and increase incidence of deficiencies of certain plant nutrients especially sulphur and zinc. On the basis of available information, nutritional requirement, uptake values, crop response and measures to overcome S deficiency are some of the aspects critically dealt with

Pāhoehoe, `a`ā, and block lava: an illustrated history of the nomenclature

Science.gov (United States)

Harris, Andrew J. L.; Rowland, Scott K.; Villeneuve, Nicolas; Thordarson, Thor

2017-01-01

Lava flows occur worldwide, and throughout history, various cultures (and geologists) have described flows based on their surface textures. As a result, surface morphology-based nomenclature schemes have been proposed in most languages to aid in the classification and distinction of lava surface types. One of the first to be published was likely the nine-class, Italian-language description-based classification proposed by Mario Gemmellaro in 1858. By far, the most commonly used terms to describe lava surfaces today are not descriptive but, instead, are merely words, specifically the Hawaiian words `a`ā (rough brecciated basalt lava) and pāhoehoe (smooth glassy basalt lava), plus block lava (thick brecciated lavas that are typically more silicic than basalt). `A`ā and pāhoehoe were introduced into the Western geological vocabulary by American geologists working in Hawai`i during the 1800s. They and other nineteenth century geologists proposed formal lava-type classification schemes for scientific use, and most of them used the Hawaiian words. In 1933, Ruy Finch added the third lava type, block lava, to the classification scheme, with the tripartite system being formalized in 1953 by Gordon Macdonald. More recently, particularly since the 1980s and based largely on studies of lava flow interiors, a number of sub-types and transitional forms of all three major lava types have been defined. This paper reviews the early history of the development of the pāhoehoe, `a`ā, and block lava-naming system and presents a new descriptive classification so as to break out the three parental lava types into their many morphological sub-types.

Flood-inundation maps for Indian Creek and Tomahawk Creek, Johnson County, Kansas, 2014

Science.gov (United States)

Peters, Arin J.; Studley, Seth E.

2016-01-25

Digital flood-inundation maps for a 6.4-mile upper reach of Indian Creek from College Boulevard to the confluence with Tomahawk Creek, a 3.9-mile reach of Tomahawk Creek from 127th Street to the confluence with Indian Creek, and a 1.9-mile lower reach of Indian Creek from the confluence with Tomahawk Creek to just beyond the Kansas/Missouri border at State Line Road in Johnson County, Kansas, were created by the U.S. Geological Survey in cooperation with the city of Overland Park, Kansas. The flood-inundation maps, which can be accessed through the U.S. Geological Survey Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the U.S. Geological Survey streamgages on Indian Creek at Overland Park, Kansas; Indian Creek at State Line Road, Leawood, Kansas; and Tomahawk Creek near Overland Park, Kansas. Near real time stages at these streamgages may be obtained on the Web from the U.S. Geological Survey National Water Information System at http://waterdata.usgs.gov/nwis or the National Weather Service Advanced Hydrologic Prediction Service at http://water.weather.gov/ahps/, which also forecasts flood hydrographs at these sites.Flood profiles were computed for the stream reaches by means of a one-dimensional step-backwater model. The model was calibrated for each reach by using the most current stage-discharge relations at the streamgages. The hydraulic models were then used to determine 15 water-surface profiles for Indian Creek at Overland Park, Kansas; 17 water-surface profiles for Indian Creek at State Line Road, Leawood, Kansas; and 14 water-surface profiles for Tomahawk Creek near Overland Park, Kansas, for flood stages at 1-foot intervals referenced to the streamgage datum and ranging from bankfull to the next interval above the 0.2-percent annual exceedance probability flood level (500-year recurrence interval). The

Owyhee River intracanyon lava flows: does the river give a dam?

Science.gov (United States)

Ely, Lisa L.; Brossy, Cooper C.; House, P. Kyle; Safran, Elizabeth B.; O'Connor, Jim E.; Champion, Duane E.; Fenton, Cassandra R.; Bondre, Ninad R.; Orem, Caitlin A.; Grant, Gordon E.; Henry, Christopher D.; Turrin, Brent D.

2013-01-01

Rivers carved into uplifted plateaus are commonly disrupted by discrete events from the surrounding landscape, such as lava flows or large mass movements. These disruptions are independent of slope, basin area, or channel discharge, and can dominate aspects of valley morphology and channel behavior for many kilometers. We document and assess the effects of one type of disruptive event, lava dams, on river valley morphology and incision rates at a variety of time scales, using examples from the Owyhee River in southeastern Oregon. Six sets of basaltic lava flows entered and dammed the river canyon during two periods in the late Cenozoic ca. 2 Ma–780 ka and 250–70 ka. The dams are strongly asymmetric, with steep, blunt escarpments facing up valley and long, low slopes down valley. None of the dams shows evidence of catastrophic failure; all blocked the river and diverted water over or around the dam crest. The net effect of the dams was therefore to inhibit rather than promote incision. Once incision resumed, most of the intracanyon flows were incised relatively rapidly and therefore did not exert a lasting impact on the river valley profile over time scales >106 yr. The net long-term incision rate from the time of the oldest documented lava dam, the Bogus Rim lava dam (≤1.7 Ma), to present was 0.18 mm/yr, but incision rates through or around individual lava dams were up to an order of magnitude greater. At least three lava dams (Bogus Rim, Saddle Butte, and West Crater) show evidence that incision initiated only after the impounded lakes filled completely with sediment and there was gravel transport across the dams. The most recent lava dam, formed by the West Crater lava flow around 70 ka, persisted for at least 25 k.y. before incision began, and the dam was largely removed within another 35 k.y. The time scale over which the lava dams inhibit incision is therefore directly affected by both the volume of lava forming the dam and the time required for sediment

LAVA Pressure Transducer Trade Study

Science.gov (United States)

Oltman, Samuel B.

2016-01-01

The Regolith and Environment Science and Oxygen and Lunar Volatile Extraction (RESOLVE) payload will transport the (LAVA) subsystem to hydrogen-rich locations on the moon supporting NASA's in-situ resource utilization (ISRU) programs. There, the LAVA subsystem will analyze volatiles that evolve from heated regolith samples in order to quantify how much water is present. To do this, the system needs resilient pressure transducers (PTs) to calculate the moles in the gas samples. The PT trade study includes a comparison of newly-procured models to a baseline unit with prior flight history in order to determine the PT model with the best survivability in flight-forward conditions.

Paleomagnetism of Holocene lava flows from the Reykjanes Peninsula and the Tungnaá lava sequence (Iceland): implications for flow correlation and ages

Science.gov (United States)

Pinton, Annamaria; Giordano, Guido; Speranza, Fabio; Þórðarson, Þorvaldur

2018-01-01

The impact of Holocene eruptive events from hot spots like Iceland may have had significant global implications; thus, dating and knowledge of past eruptions chronology is important. However, at high-latitude volcanic islands, the paucity of soils severely limits 14C dating, while the poor K content of basalts strongly restricts the use of K/Ar and Ar/Ar methods. Even tephrochronology, based on 14C age determinations, refers to layers that rarely lie directly above lava flows to be dated. We report on the paleomagnetic dating of 25 sites from the Reykjanes Peninsula and the Tungnaá lava sequence of Iceland. The gathered paleomagnetic directions were compared with the available reference paleosecular variation curves of the Earth magnetic field to obtain the possible emplacement age intervals. To test the method's validity, we sampled the precisely dated Laki (1783-1784 AD) and Eldgjà (934-938 AD) lavas. The age windows obtained for these events encompass the true flow ages. For sites from the Reykjanes peninsula and the Tugnaá lava sequence, we derived multiple possible eruption events and ages. In the Reykjanes peninsula, we propose an older emplacement age (immediately following the 870 AD Iceland Settlement age) for Ogmundarhraun and Kapelluhraun lava fields. For pre-historical (older than the settlement age) Tugnaá eruptions, the method has a dating precision of 300-400 years which allows an increase of the detail in the chronostratigraphy and distribution of lavas in the Tugnaá sequence.

Disruption of tephra fall deposits caused by lava flows during basaltic eruptions

Science.gov (United States)

Brown, R. J.; Thordarson, T.; Self, S.; Blake, S.

2015-10-01

Observations in the USA, Iceland and Tenerife, Canary Islands reveal how processes occurring during basaltic eruptions can result in complex physical and stratigraphic relationships between lava and proximal tephra fall deposits around vents. Observations illustrate how basaltic lavas can disrupt, dissect (spatially and temporally) and alter sheet-form fall deposits. Complexity arises through synchronous and alternating effusive and explosive activity that results in intercalated lavas and tephra deposits. Tephra deposits can become disrupted into mounds and ridges by lateral and vertical displacement caused by movement (including inflation) of underlying pāhoehoe lavas and clastogenic lavas. Mounds of tephra can be rafted away over distances of 100 s to 1,000 s m from proximal pyroclastic constructs on top of lava flows. Draping of irregular topography by fall deposits and subsequent partial burial of topographic depressions by later lavas can result in apparent complexity of tephra layers. These processes, deduced from field relationships, have resulted in considerable stratigraphic complexity in the studied proximal regions where fallout was synchronous or alternated with inflation of subjacent lava sheets. These mechanisms may lead to diachronous contact relationships between fall deposits and lava flows. Such complexities may remain cryptic due to textural and geochemical quasi-homogeneity within sequences of interbedded basaltic fall deposits and lavas. The net effect of these processes may be to reduce the usefulness of data collected from proximal fall deposits for reconstructing basaltic eruption dynamics.

Mathematical modelling of demineralisation of high sulphur coal by bioleaching

Energy Technology Data Exchange (ETDEWEB)

Weerasekara, N.S.; Frutos, F.J.G.; Cara, J.; Lockwood, F.C. [University of London Imperial College of Science Technology & Medicine, London (United Kingdom)

2008-02-15

During coal combustion various toxic compounds are generated from its sulphur content. Their environmental impacts are considered to be very important. While there are various conventional preparation methods to remove the sulphur in the fuel, recent work reveals that newly-isolated micro-organisms, naturally present in coal, have the ability to reduce its sulphur content. The removal of sulphur using biological leaching involving acidophilic iron oxidising bacteria like Acidithiobacillus ferrooxidans and Leptospirillum ferrooxidans are examined and a computational technique based on computational fluid dynamics is developed to model the biological leaching of sulphur from coal. The model was validated against a pack-column experiment carried out for iron separation during 60 days. The mathematical model predicted iron separation over time is similar to experimental measurements, with an average difference of 5.5%. According to the experimental results, there was an overall reduction of 33% of pyrite, whereas the model prediction was 32%. The model results shows overall good agreement with pack-column experimental data.

Hawaii Volcanism: Lava Forms

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Over the last several million years the Hawaiian Islands have been built of successive lava flows. They are the most recent additions in a long line of volcanoes...

Drained Lava Tubes and Lobes From Eocretaceous Paraná-Etendeka Province, Brazil

Science.gov (United States)

Waichel, B. L.; Lima, E. F. D.; Mouro, L. D.; Briske, D. R.; Tratz, E. B.

2017-12-01

The identification of lava tubes in continental flood basalt provinces (CFBP) is difficult and reports of preserved drained tubes and lobes are rare. The large extension of CFBP must be related to an efficient transport of lava and tubes are the most efficient mechanism to transport lava in insulated pathways, like observed in modern volcanic fields. Looking for caves in the central portion of Paraná-Etendeka Province, we discovered drained lava tubes (4) and lobes (6) in a volcanic sequence constituted by pahoehoe flows. Lava tubes are: Casa de Pedra, Perau Branco, Dal Pae and Pinhão. The Casa de Pedra tube system is composed of two principal chambers with similar dimensions, reaching up to 10 m long and 4.0 m high connected by a narrow passage. The general form of the chamber is hemispherical, with re-entrances of ellipsoidal shape probably formed by small lava lobes and collapse structures in the roof. The second chamber is connected with three secondary lava tubes. Columns in the cave are formed when the flowing lava separates in two lava channels that join again further down the system, forming and anastomosing tube network. Lateral lava benches and lava drainings at the walls are observed in secondary tubes. The general lava flow is to SW. The Perau Branco system is composed of five tubes with ellipsoidal openings. The main features are the long tubes that emerge from the small flattened chambers. One tube is more than 20 m long, with alternating circular and flattened ellipsoidal sections. The general lava flow is to NE. Pinhão tube is spherical with 3 meters diameter and 15 m long, with lava flow orientation to NW. This tube has a bottleneck shape with linings (up to 3 cm thick), which are observed in the roof and walls. Dal Pae Tube is 10 m long with an ellipsoidal opening, bottleneck shape and orientation to NE. The lava flow directions measured in the tubes is to SW (Casa de Pedra, Pinhão) and NE (Perau Branco, Dal Pae) and this pattern is related to

The reducibility of sulphuric acid and sulphate in aqueous solution

International Nuclear Information System (INIS)

Grauer, R.

1991-07-01

In connection with the Swedish project for final storage of spent fuel elements it was necessary to assess whether dissolved sulphate can corrode the copper canister. A simple reaction between copper and sulphate is thermodynamically impossible, but copper can react to give copper sulphide if an additional electron donor such as iron(II) is available. The problem was extended to the more general question of the reducibility of sulphur(VI) in dilute aqueous solution. Chemical reduction of sulphate does not take place in dilute solution at temperatures below 100 o C. In experiments on the reduction of sulphates under hydrothermal conditions a reaction only takes place at temperatures above 275-300 o C. The oxidising action of sulphuric acid on metals becomes perceptible only at acid concentrations over 45-50%. In experiments on the cathodic reduction of 74% sulphuric acid the formation of hydrogen sulphide and elementary sulphur starts, depending on the current density, at 50-130 o C, and polarographic measurements suggest that the reducible species is not the hydrogen sulphate ion but molecular sulphuric acid. The resistance of copper to oxygen-free sulphuric acid up to a concentration of 60% is well-known. Numerous processes in industrial electrochemistry take place in sulphuric acid or sulphate electrolytes. The reversible metal/metal-sulphate electrodes of lead and cadmium are unstable relative to the corresponding metal sulphides. Nevertheless the reversible lead sulphate electrode does not fail from sulphide formation. All these facts confirm that sulphur(VI) in dilute solution is completely inert towards chemical reducing agents and also to cathodic reduction. Thus corrosion of copper by sulphate under final-storage conditions and in the absence of sulphate reducing bacteria can be almost certainly be ruled out. (author) 5 figs., 85 refs

Explosive Volcanism in Io's Lava Lakes - The Key To Constraining Eruption Temperature?

Science.gov (United States)

Davies, A. G.; Keszthelyi, L. P.; McEwen, A. S.

2010-12-01

Active lava lakes are open volcanic systems, where lava circulates between a magma chamber and the surface. Rare on Earth, lava lakes may be common on Io, the highly volcanic jovian moon (e.g., [1]). Io’s low atmospheric pressure means that activity within Io’s lava lakes may be explosive, exposing lava at near-liquid temperatures (currently poorly constrained for Io). Lava lakes are therefore important targets for future missions to Io [2, 3]. With this in mind, hand-held infrared imagers were used to collect thermal emission data from the phonolite Erebus (Antarctica) lava lake [4] and the basalt lava lake at Erta’Ale (Ethiopia). Temperature-area distributions and the integrated thermal emission spectra for each lava lake were determined from the data. These calculated spectra have been used to test models developed for analysis of remote sensing data of lava lakes and lava flows on both Earth and Io, where no ground-truth exists. The silicate cooling model [5] assumes, for the lava lake model variant, that the existing surface crust has been created at a fixed rate. Model output consists of a synthesized thermal emission spectrum, estimate of surface age range, and a rate of surface crust area formation. The cooling model provides accurate reproductions of actual thermal spectra and the total emitting area to within a few percent of actual emitting area. Model resurfacing rates broadly agree with observed behaviour at both lakes. Despite different composition lavas, the short-wavelength infrared thermal emission spectra from the two terrestrial lava lakes studied are very similar in shape, and, importantly, bear a striking similarity to spectra of Pele, an Io volcano that has been proposed to be a persistent, active lava lake [6] and which is the source of a 300-km high dust and gas plume. Our study of the cooling of the hottest lava exposed at Erta’Ale yields constraints on the ability of multispectral imagers to determine eruption temperature. We find

Steel Creek water quality: L-Lake/Steel Creek Biological Monitoring Program, November 1985--December 1991

International Nuclear Information System (INIS)

Bowers, J.A.; Kretchmer, D.W.; Chimney, M.J.

1992-04-01

The Savannah River Site (SRS) encompasses 300 sq mi of the Atlantic Coastal Plain in west-central South Carolina. The Savannah River forms the western boundary of the site. Five major tributaries of the Savannah River -- upper Three Runs Creek, Four Mile Creek, Pen Branch, Steel Creek, and Lower Three Runs Creek -- drain the site. All but Upper Three Runs Creek receive, or in the past received, thermal effluents from nuclear production reactors. In 1985, L Lake, a 400-hectare cooling reservoir, was built on the upper reaches of Steel Creek to receive effluent from the restart of L-Reactor, and protect the lower reaches from thermal impacts. The Steel Creek Biological Monitoring Program was designed to meet envirorunental regulatory requirements associated with the restart of L-Reactor and complements the Biological Monitoring Program for L Lake. This extensive program was implemented to address portions of Section 316(a) of the Clean Water Act. The Department of Energy (DOE) must demonstrate that the operation of L-Reactor will not significantly alter the established aquatic ecosystems

Effects of acid conditions on element distribution beneath a sulphur basepad

International Nuclear Information System (INIS)

Sevigny, J.H.; Fennell, J.W.; Sharma, A.

1997-04-01

A reconnaissance-scale study was conducted to determine the extent of acid conditions beneath a sulphur basepad at Canadian Occidental's Balzac sour gas plant and to examine the effects of acid conditions on element distribution in the subsurface. Sulphur which is extracted from sour natural gas is stored in large blocks directly on the ground. The elemental sulphur will oxidize to H 2 SO 4 under aerobic conditions and with the proper microorganisms can result in possible removal of metals from the soil and transportation in the groundwater. The basepad at the sour gas plant is 36 years old and is covered by about 1 metre of elemental sulphur. EM31 terrain conductivity and electrical resistivity tomography geophysical surveys were conducted to determine aerial and subsurface bulk electrical conductivity. The objective was to locate the indurated layer using the geophysical techniques and soil boring. The extent of acid conditions beneath the sulphur block was determined. Migration rates for the site were also estimated. Results suggested that minimal soil and groundwater impact can be expected from sulphur blocks overlying properly buffered soils, and that synthetic liners beneath sulphur blocks may not be a necessary measure at sour gas plants in Alberta. 19 refs., 6 tabs., 6 figs., 5 appendices

Sulphur Extraction at Bryan Mound

Energy Technology Data Exchange (ETDEWEB)

Kirby, Carolyn L [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lord, Anna C. Snider [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2015-08-01

The Bryan Mound caprock was subjected to extens ive sulphur mining prior to the development of the Strategic Petroleum Reserve. Undoubtedl y, the mining has modified the caprock integrity. Cavern wells at Bryan Mound have been subject to a host of well integr ity concerns with many likely compromised by the cavernous capro ck, surrounding corrosive environment (H ₂ SO ₄ ), and associated elevated residual temperatures al l of which are a product of the mining activities. The intent of this study was to understand the sulphur mining process and how the mining has affected the stability of the caprock and how the compromised caprock has influenced the integrity of the cavern wells. After an extensiv e search to collect pert inent information through state agencies, literature sear ches, and the Sandia SPR librar y, a better understanding of the caprock can be inferred from the knowledge gaine d. Specifically, the discovery of the original ore reserve map goes a long way towards modeling caprock stability. In addition the gained knowledge of sulphur mining - subs idence, superheated corrosive wa ters, and caprock collapse - helps to better predict the post mi ning effects on wellbore integrity. This page intentionally left blank

Multifractal characterization of Vesuvio lava-flow margins and its implications

Science.gov (United States)

Luongo, G.; Mazzarella, A.; Di Donna, G.

2000-09-01

The digitized lava-flow margins of well-defined extended eruptions occurring at Vesuvio in 1760, 1794, 1861, 1906, 1929 and 1944 are found to follow fractal behaviours inside a scaling region enclosed between 50 and 400 m. Although the invariance region is well respected, the fractal dimension D varies from one lava flow to another: the more irregular the lava-flow margin, the larger the value of D. The ascertained dependence of D on the duration of premonitory activity, preceding the emission of lavas, might provide some insight into the inner volcanic processes before the eruption and into the dynamical processes operating during flow emplacement.

Sulphur isotope measurements on sulphates from Antarctic atmospheric precipitations, lake waters and salt efflorescences: a contribution to the study of the natural sulphur cycle

International Nuclear Information System (INIS)

Wand, U.; Maass, I.; Haendel, D.

1987-01-01

Sulphur isotope analyses are an important tool for the study of the natural sulphur cycle. However, on the northern hemisphere such studies particularly of the atmospheric component of the cycle are seriously hampered and in many regions practically impossible because of the high emission rate of anthropogenic sulphur. Only in remote areas of the world such as the Antarctic 34 S analyses can be used with success to identify the various natural sulphur sources (marine, biogenic and volcanic sources). We report here preliminary results of 34 S isotope measurements on sulphates from recent atmospheric precipitations (snow), lake waters and salt efflorescences sampled in the Schirmacher Oasis and the Wohlthat Massif, central Queen Maud Land, East Antarctica. Except for 4 efflorescence samples the sulphates investigated in this work are enriched in 34 S relative to the meteoritic sulphur standard (CDT). On an average the sulphates of our study area are isotopically lighter than those from the McMurdo region, South Victoria land. The latter region is characterized by the predominance of salts of marine origin. (author)

75 FR 40034 - Northeastern Tributary Reservoirs Land Management Plan, Beaver Creek, Clear Creek, Boone, Fort...

Science.gov (United States)

2010-07-13

... TENNESSEE VALLEY AUTHORITY Northeastern Tributary Reservoirs Land Management Plan, Beaver Creek...-managed public land on Beaver Creek, Clear Creek, Boone, Fort Patrick Henry, South Holston, Watauga, and... Proposed Land Use Alternative) identified in the final environmental impact statement (FEIS). Under the...

Mauna Loa lava accumulation rates at the Hilo drill site: Formation of lava deltas during a period of declining overall volcanic growth

Science.gov (United States)

Lipman, P.W.; Moore, J.G.

1996-01-01

Accumulation rates for lava flows erupted from Mauna Loa, as sampled in the uppermost 280 m of the Hilo drill hole, vary widely for short time intervals (several thousand years), but overall are broadly similar to those documented elsewhere on this volcano since 100 ka. Thickness variations and accumulation rates for Mauna Loa lavas at the Hilo drill site have been strongly affected by local paleotopography, including funneling and ponding between Mauna Kea and Kilauea. In addition, gentle submerged slopes of Mauna Kea in Hilo Bay have permitted large shoreline displacements by Mauna Loa flows. Ages of eruptive intervals have been determined from published isotopic data and from eustatic sea level curves modified to include the isostatic subsidence of the island of Hawaii at 2.2-2.6 mm/yr. Prior to 10 ka, rates of Mauna Loa lava accumulation at the drill site varied from 0.6 to 4.3 mm/yr for dateable intervals, with an overall rate of 1.8 mm/yr. Major eruptive pulses at about 1.3 and 10 ka, each probably representing a single long-lived eruption based on lack of weathering between flow units, increase the overall accumulation rate to 2.4 mm/yr. The higher rate since 10 ka reflects construction of thick near-shoreline lava deltas as postglacial sea levels rose rapidly. Large lava deltas form only along coastal segments where initially subaerial slopes have been submerged by the combined effects of eustatic sea level rise, isostatic subsidence, or spreading of volcano flanks. Overall accumulation of 239 m of lava at the drill site since 100-120 ka closely balances submergence of the Hilo area, suggesting that processes of coastal lava deposition have been modulated by rise in sea level. The Hilo accumulation rate is slightly higher than average rates of 1-2 mm/yr determined elsewhere along the Mauna Loa coast, based on rates of shoreline coverage and dated sea cliff and fault scarp exposures. Low rates of coastal lava accumulation since 100 ka, near or below the rate

Internal fabric development in complex lava domes

Czech Academy of Sciences Publication Activity Database

Závada, Prokop; Kratinová, Zuzana; Kusbach, V.; Schulmann, K.

2009-01-01

Roč. 466, č. 1-2 (2009), s. 101-113 ISSN 0040-1951 R&D Projects: GA AV ČR KJB301110703; GA AV ČR KJB300120702 Grant - others:GA ČR(CZ) GA205/03/0204 Institutional research plan: CEZ:AV0Z30120515 Keywords : analogue modeling * lava extrusion * exogenous growth * crystal-rich lava * AMS Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.935, year: 2009

78 FR 62616 - Salmon Creek Hydroelectric Company, Salmon Creek Hydroelectric Company, LLC; Notice of Transfer...

Science.gov (United States)

2013-10-22

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 3730-005] Salmon Creek Hydroelectric Company, Salmon Creek Hydroelectric Company, LLC; Notice of Transfer of Exemption 1. By letter filed September 23, 2013, Salmon Creek Hydroelectric Company informed the Commission that they have...

Gypsum speleothems in lava tubes from Lanzarote, Canary Islands. Did you say gypsum?

OpenAIRE

Huerta, Pedro; Martín-García, Rebeca; Rodríguez-Berriguete, Álvaro; Iglesia, A. la; Martín-Pérez, Andrea; Alonso-Zarza, Ana María

2015-01-01

Lanzarote is the easternmost island of the volcanic Canary archipielago considered together with Fuerteventura the low relief islands of the archipielago. These island receive less rain than 300 mm/year. Basaltic lava flows preserves lava tubes formed during cooling and solidification of external parts of lava, while internal parts were still hot and flowing. When lava flow stopped the lava abandoned the tubes, and the tubes preserved empty. These tubes actuate as caves and som...

A meta-analysis of aneurysm formation in laser assisted vascular anastomosis (LAVA)

Science.gov (United States)

Chen, Chen; Peng, Fei; Xu, Dahai; Cheng, Qinghua

2009-08-01

Laser assisted vascular anastomosis (LAVA) is looked as a particularly promising non-suture method in future. However, aneurysm formation is one of the main reasons delay the clinical application of LAVA. Some scientists investigated the incidence of aneurysms in animal model. To systematically analyze the literature on reported incidence of aneurysm formation in LAVA therapy, we performed a meta-analysis comparing LAVA with conventional suture anastomosis (CSA) in animal model. Data were systematically retrieved and selected from PUBMED. In total, 23 studies were retrieved. 18 studies were excluded, and 5 studies involving 647 animals were included. Analysis suggested no statistically significant difference between LAVA and CSA (OR 1.24, 95%CI 0.66-2.32, P=0.51). Result of meta analysis shows that the technology of LAVA is very close to clinical application.

Big Bayou Creek and Little Bayou Creek Watershed Monitoring Program

Energy Technology Data Exchange (ETDEWEB)

Kszos, L.A.; Peterson, M.J.; Ryon; Smith, J.G.

1999-03-01

Biological monitoring of Little Bayou and Big Bayou creeks, which border the Paducah Site, has been conducted since 1987. Biological monitoring was conducted by University of Kentucky from 1987 to 1991 and by staff of the Environmental Sciences Division (ESD) at Oak Ridge National Laboratory (ORNL) from 1991 through March 1999. In March 1998, renewed Kentucky Pollutant Discharge Elimination System (KPDES) permits were issued to the US Department of Energy (DOE) and US Enrichment Corporation. The renewed DOE permit requires that a watershed monitoring program be developed for the Paducah Site within 90 days of the effective date of the renewed permit. This plan outlines the sampling and analysis that will be conducted for the watershed monitoring program. The objectives of the watershed monitoring are to (1) determine whether discharges from the Paducah Site and the Solid Waste Management Units (SWMUs) associated with the Paducah Site are adversely affecting instream fauna, (2) assess the ecological health of Little Bayou and Big Bayou creeks, (3) assess the degree to which abatement actions ecologically benefit Big Bayou Creek and Little Bayou Creek, (4) provide guidance for remediation, (5) provide an evaluation of changes in potential human health concerns, and (6) provide data which could be used to assess the impact of inadvertent spills or fish kill. According to the cleanup will result in these watersheds [Big Bayou and Little Bayou creeks] achieving compliance with the applicable water quality criteria.

Being green on sulphur: Targets, measures and side-effects

DEFF Research Database (Denmark)

Kontovas, Christos A.; Panagakos, George; Psaraftis, Harilaos N.

2016-01-01

to sea to reduce congestion, and might ultimately (under certain circumstances) increase the overall level of CO2 emissions along the entire supply chain. The purpose of this chapter is to investigate the potential effect of sulphur regulations on the share of cargo transported by the waterborne mode vis......Green House Gas (GHG) emissions are not the only emissions of concern to the international transport community. SOx emissions are non-GHG emissions that are caused by the presence of sulphur in the fuel. As the maximum percentage of sulphur in automotive and aviation fuels is strictly regulated...

Distribution and isotopic abundance of sulphur in recent marine sediments off southern California

Energy Technology Data Exchange (ETDEWEB)

Kaplan, I R; Emergy, K O; Rittenberg, S C

1963-01-01

Analyses of sulphur compounds in basin sediments off southern California indicate that elemental sulphur, free sulphide, hydrotroilite, organic sulphur, sulphate and pyrite are present in quantities that vary with environment and depth in the sediments. Pyrite is generally the most abundant form, occurring in oxidizing as well as in reducing sediments and often constituting 90% of total sulphur. A material balance indicates that the total sulphur content is far in excess of the sulphate-sulphur initially trapped in the interstitial water. This evidence, together with failure to detect significant alternate sources, suggests that sulphate-sulphur is extracted from the overlying sea water at the sediment-water interface. Isotope measurements confirm many of the conclusions suggested by the quantitative chemical analyses. The show that biological sulphate reduction is the single most important process in the sulphur cycle. The sulphide released is converted to hydrotrolite and then to pyrite. Elemental and organic sulphur appear to be continually forming and reacting in the sediment column. The organic sulphur released from decaying organic matter apparently plays only a small role in the sulphur economy. Enrichment in S/sup 32/ ranging from 9 to 62% was measured in pyrite fragments, a spread similar to that previously observed in ancient sediments. Data from field and laboratory experiments were combined to determine rate of sulphate reduction, number of sulphate reducing bacteria and the amount of organic matter decomposed during sulphate reduction in the sediment, as well as rate of renewal of water in the basins. The results suggest that the methods used may have many applications for elucidating in situ rate processes.

Pyrotechnic countermeasures: IV. Radiometric performance of a sulphur-based Flare composition

Energy Technology Data Exchange (ETDEWEB)

Koch, Ernst-Christian [NATO Munitions Safety Information Analysis Center (MSIAC), Brussels (Belgium)

2008-10-15

Radiometric performance of a sulphur-based flare composition has been investigated. Composition comprising sulphur, potassium perchlorate and antimony sulphide has acceptable band ratio but an order of magnitude weaker spectral efficiency than typical carbon-based compositions. The use of other sulphur compounds with potential for increased performance is discussed. For part III see Ref. [1]. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

Morphometric study of pillow-size spectrum among pillow lavas

Science.gov (United States)

Walker, George P. L.

1992-08-01

Measurements of H and V (dimensions in the horizontal and vertical directions of pillows exposed in vertical cross-section) were made on 19 pillow lavas from the Azores, Cyprus, Iceland, New Zealand, Tasmania, the western USA and Wales. The median values of H and V plot on a straight line that defines a spectrum of pillow sizes, having linear dimensions five times greater at one end than at the other, basaltic toward the small-size end and andesitic toward the large-size end. The pillow median size is interpreted to reflect a control exercised by lava viscosity. Pillows erupted on a steep flow-foot slope in lava deltas can, however, have a significantly smaller size than pillows in tabular pillowed flows (inferred to have been erupted on a small depositonal slope), indicating that the slope angle also exercised a control. Pipe vesicles, generally abundant in the tabular pillowed flows and absent from the flow-foot pillows, have potential as a paleoslope indicator. Pillows toward the small-size end of the spectrum are smooth-surfaced and grew mainly by stretching of their skin, whereas disruption of the skin and spreading were important toward the large-size end. Disruption involved increasing skin thicknesses with increasing pillow size, and pillows toward the large-size end are more analogous with toothpaste lava than with pahoehoe and are inferred from their thick multiple selvages to have taken hours to grow. Pseudo-pillow structure is also locally developed. An example of endogenous pillow-lava growth, that formed intrusive pillows between ‘normal’ pillows, is described from Sicily. Isolated pillow-like bodies in certain andesitic breccias described from Iceland were previously interpreted to be pillows but have anomalously small sizes for their compositions; it is now proposed that they may lack an essential attribute of pillows, namely, the development of bulbous forms by the inflation of a chilled skin, and are hence not true pillows. Para-pillow lava is

Sulphur XANES Analysis of Cultured Human Prostate Cancer Cells

International Nuclear Information System (INIS)

Kwiatek, W.M.; Podgorczyk, M.; Paluszkiewicz, Cz.; Balerna, A.; Kisiel, A.

2008-01-01

Prostate cancer is one of the most commonly diagnosed cancers in men throughout the world. It is believed that changes to the structure of protein binding sites, altering its metabolism, may play an important role in carcinogenesis. Sulphur, often present in binding sites, can influence such changes through its chemical speciation. Hence there is a need for precise investigation of coordination environment of sulphur. X-ray absorption near edge structure spectroscopy offers such possibility. Cell culture samples offer histologically well defined areas of good homogeneity, suitable for successful and reliable X-ray absorption near edge structure analysis. This paper presents sulphur speciation data collected from three different human prostate cancer cell lines (PC-3, LNCaP and DU-145). Sulphur X-ray absorption near edge structure analysis was performed on K-edge structure. The spectra of cells were compared with those of cancerous tissue and with organic substances as well as inorganic compounds. (authors)

Concentration of volatile sulphur-containing compounds along the gastrointestinal tract of pigs fed a high-sulphur or a low-sulphur diet

DEFF Research Database (Denmark)

Poulsen, Henrik Vestergaard; Canibe, Nuria; Finster, Kai

2010-01-01

Volatile sulphur-containing compounds (VSC) are formed in large quantities in the gastrointestinal tract (GI-tract) of pigs and upon excretion from the animal; these compounds are released from the faeces causing emission of foul odour. However, very little is known about the rate and extent of t...

UAV-based remote sensing surveys of lava flow fields: a case study from Etna's 1974 channel-fed lava flows

Science.gov (United States)

Favalli, Massimiliano; Fornaciai, Alessandro; Nannipieri, Luca; Harris, Andrew; Calvari, Sonia; Lormand, Charline

2018-03-01

During an eruption, time scales of topographic change are fast and involve vertical and planimetric evolution of millimeters to meters as the event progresses. Repeat production of high spatial resolution terrain models of lava flow fields over time scales of a few hours is thus a high-value capability in tracking the buildup of the deposit. Among the wide range of terrestrial and aerial methods available to collect such topographic data, the use of an unmanned aerial vehicle (UAV) as an acquisition platform, together with structure from motion (SfM) photogrammetry, has become especially useful. This approach allows high-frequency production of centimeter-scale terrain models over kilometer-scale areas, including dangerous and inaccessible zones, with low cost and minimal hazard to personnel. This study presents the application of such an integrated UAV-SfM method to generate a high spatial resolution digital terrain model and orthomosaic of Mount Etna's January-February 1974 lava flow field. The SfM method, applied to images acquired using a UAV platform, enabled the extraction of a very high spatial resolution (20 cm) digital elevation model and the generation of a 3-cm orthomosaic covering an area of 1.35 km2. This spatial resolution enabled us to analyze the morphology of sub-meter-scale features, such as folds, blocks, and cracks, over kilometer-scale areas. The 3-cm orthomosaic allowed us to further push the analysis to centimeter-scale grain size distribution of the lava surface. Using these data, we define three types of crust structure and relate them to positions within a channel-fed ´áā flow system. These crust structures are (i) flow parallel shear lines, (ii) raft zones, and (iii) folded zones. Flow parallel shear lines are found at the channel edges, and are 2-m-wide and 0.25-m-deep zones running along the levee base and in which cracking is intense. They result from intense shearing between the moving channel lava and the static levee lava. In

Thermal Remote Sensing of Lava Lakes on Io and Earth (Invited)

Science.gov (United States)

Davies, A. G.; Keszthelyi, L. P.; McEwen, A. S.

2013-12-01

Volcanology has been transformed by remote sensing. For decades, Earth's volcanoes have been studied in the infrared by a wide variety of instruments on spacecraft at widely varying spectral, spatial and temporal resolutions, for which techniques have been developed to interpret and understand ongoing volcanic eruptions. The study of volcanism on Io, the only Solar System body besides Earth known to have ongoing, high temperature, silicate-based effusive and explosive volcanic eruptions, requires new remote sensing techniques. The extraordinary volcanism allows us to examine Io's interior and composition from the material erupted onto the surface. For Io, the biggest question in the wake of NASA's Galileo mission concerns the eruption temperature of Io's dominant silicate lavas [1,2]. Constraining eruption temperature constrains magma composition, in turn a reflection of the composition, physical state and tidal heating within Io. However, the extraction of lava eruption temperature from remote sensing data is difficult. Detector saturation is likely except when the hot material fills a tiny fraction of a resolution element, unless instruments are designed for this objective. High temperature lava surfaces cool rapidly, so remote observations can miss the peak temperature. Observations at different wavelengths must be acquired nearly simultaneously to derive accurate temperatures of very hot and dynamic sources [3]. Uncertainties regarding hot lava emissivity [4] also reduce the confidence in derived temperatures. From studying thermal emission data from different styles of volcanic activity on Earth by remote sensing in conjunction with contemporaneous observations on the ground, it is found that only certain styles of volcanic activity are suitable for deriving liquid lava temperatures [3]. Active lava lakes are particularly useful, especially during a phase of lava fountaining. Examination and analysis of FLIR data obtained at the Erta'Ale (Ethiopia) basaltic

Steel Creek primary producers: Periphyton and seston, L-Lake/Steel Creek Biological Monitoring Program, January 1986--December 1991

Energy Technology Data Exchange (ETDEWEB)

Bowers, J.A. [Westinghouse Savannah River Co., Aiken, SC (United States); Toole, M.A.; van Duyn, Y. [Normandeau Associates Inc., New Ellenton, SC (United States)

1992-02-01

The Savannah River Site (SRS) encompasses 300 sq mi of the Atlantic Coastal Plain in west-central South Carolina. Five major tributaries of the Savannah River -- Upper Three Runs Creek, Four Mile Creek, Pen Branch, Steel Creek, and Lower Three Runs Creek -- drain the site. In 1985, L Lake, a 400-hectare cooling reservoir, was built on the upper reaches of Steel Creek to receive effluent from the restart of L-Reactor and to protect the lower reaches from thermal impacts. The Steel Creek Biological Monitoring Program was designed to assess various components of the system and identify and changes due to the operation of L-Reactor or discharge from L Lake. An intensive ecological assessment program prior to the construction of the lake provided baseline data with which to compare data accumulated after the lake was filled and began discharging into the creek. The Department of Energy must demonstrate that the operation of L-Reactor will not significantly alter the established aquatic ecosystems. This report summarizes the results of six years` data from Steel Creek under the L-Lake/Steel Creek Monitoring Program. L Lake is discussed separately from Steel Creek in Volumes NAI-SR-138 through NAI-SR-143.

Steel Creek primary producers: Periphyton and seston, L-Lake/Steel Creek Biological Monitoring Program, January 1986--December 1991

International Nuclear Information System (INIS)

Bowers, J.A.; Toole, M.A.; van Duyn, Y.

1992-02-01

The Savannah River Site (SRS) encompasses 300 sq mi of the Atlantic Coastal Plain in west-central South Carolina. Five major tributaries of the Savannah River -- Upper Three Runs Creek, Four Mile Creek, Pen Branch, Steel Creek, and Lower Three Runs Creek -- drain the site. In 1985, L Lake, a 400-hectare cooling reservoir, was built on the upper reaches of Steel Creek to receive effluent from the restart of L-Reactor and to protect the lower reaches from thermal impacts. The Steel Creek Biological Monitoring Program was designed to assess various components of the system and identify and changes due to the operation of L-Reactor or discharge from L Lake. An intensive ecological assessment program prior to the construction of the lake provided baseline data with which to compare data accumulated after the lake was filled and began discharging into the creek. The Department of Energy must demonstrate that the operation of L-Reactor will not significantly alter the established aquatic ecosystems. This report summarizes the results of six years' data from Steel Creek under the L-Lake/Steel Creek Monitoring Program. L Lake is discussed separately from Steel Creek in Volumes NAI-SR-138 through NAI-SR-143

Heat transfer measurements of the 1983 kilauea lava flow.

Science.gov (United States)

Hardee, H C

1983-10-07

Convective heat flow measurements of a basaltic lava flow were made during the 1983 eruption of Kilauea volcano in Hawaii. Eight field measurements of induced natural convection were made, giving heat flux values that ranged from 1.78 to 8.09 kilowatts per square meter at lava temperatures of 1088 and 1128 degrees Celsius, respectively. These field measurements of convective heat flux at subliquidus temperatures agree with previous laboratory measurements in furnace-melted samples of molten lava, and are useful for predicting heat transfer in magma bodies and for estimating heat extraction rates for magma energy.

Petrogenesis of basalt-trachyte lavas from Olmoti Crater, Tanzania

Science.gov (United States)

Mollel, Godwin F.; Swisher, Carl C., III; McHenry, Lindsay J.; Feigenson, Mark D.; Carr, Michael J.

2009-08-01

Olmoti Crater is part of the Plio-Pleistocene Ngorongoro Volcanic Highland (NVH) in northern Tanzania to the south of Gregory Rift. The Gregory Rift is part of the eastern branch of the East African Rift System (EARS) that stretches some 4000 km from the Read Sea and Gulf of Aden in the north to the Zambezi River in Mozambique. Here, we (1) characterize the chemistry and mineral compositions of lavas from Olmoti Crater, (2) determine the age and duration of Olmoti volcanic activity through 40Ar/ 39Ar dating of Olmoti Crater wall lavas and (3) determine the genesis of Olmoti lavas and the relationship to other NVH and EARS volcanics and (4) their correlation with volcanics in the Olduvai and Laetoli stratigraphic sequences. Olmoti lavas collected from the lower part of the exposed crater wall section (OLS) range from basalt to trachyandesite whereas the upper part of the section (OUS) is trachytic. Petrography and major and trace element data reflect a very low degree partial melt origin for the Olmoti lavas, presumably of peridotite, followed by extensive fractionation. The 87Sr/ 86Sr data overlap whereas Nd and Pb isotope data are distinct between OLS and OUS samples. Interpretation of the isotope data suggests mixing of enriched mantle (EM I) with high-μ-like reservoirs, consistent with the model of Bell and Blenkinsop [Bell, K., Blenkinsop, J., 1987. Nd and Sr isotopic compositions of East African carbonatites: implications for mantle heterogeneity. Geology 5, 99-102] for East African carbonatite lavas. The isotope ratios are within the range of values defined by Oceanic Island Basalt (OIB) globally and moderate normalized Tb/Yb ratios (2.3-1.6) in these lavas suggest melting in the lithospheric mantle consistent with other studies in the region. 40Ar/ 39Ar incremental-heating analyses of matrix and anorthoclase separates from Olmoti OLS and OUS lavas indicate that volcanic activity was short in duration, lasting ˜200 kyr from 2.01 ± 0.03 Ma to 1.80 ± 0

New Insights to the Mid Miocene Calc-alkaline Lavas of the Strawberry Volcanics, NE Oregon Surrounded by the Coeval Tholeiitic Columbia River Basalt Province

Science.gov (United States)

Steiner, A. R.; Streck, M. J.

2013-12-01

The Strawberry Volcanics (SV) of NE Oregon were distributed over 3,400 km2 during the mid-Miocene and comprise a diverse volcanic suite, which span the range of compositions from basalt to rhyolite. The predominant composition of this volcanic suite is calc-alkaline (CA) basaltic andesite and andesite, although tholeiitic (TH) lavas of basalt to andesite occur as well. The coeval flood basalts of the Columbia River province surround the SV. Here we will discuss new ages and geochemical data, and present a new geologic map and stratigraphy of the SV. The SV are emplaced on top of pre-Tertiary accreted terranes of the Blue Mountain Province, Mesozoic plutonic rocks, and older Tertiary volcanic rocks thought to be mostly Oligocene of age. Massive rhyolites (~300 m thick) are exposed mainly along the western flank and underlie the intermediate composition lavas. In the southern portion of this study area, alkali basaltic lavas, thought to be late Miocene to early Pliocene in age, erupted and overlie the SV. In addition, several regional ignimbrites reach into the area. The 9.7 Ma Devine Canyon Tuff and the 7.1 Ma Rattlesnake Tuff also overlie the SV. The 15.9-15.4 Ma Dinner Creek Tuff is mid-Miocene, and clear stratigraphic relationships are found in areas where the tuff is intercalated between thick SV lava flows. All of the basalts of the SV are TH and are dominated by phenocryst-poor (≤2%) lithologies. These basalts have an ophitic texture dominated by plagioclase, clinopyroxene and olivine (often weathered to iddingsite). Basalts and basaltic andesites have olivine Fo #'s ranging from 44 at the rims (where weathered to iddingsite) and as high as 88 at cores. Pyroxene Mg #'s range from 65 to 85. Andesites of the SV are sub-alkaline, and like the basalts, are exceedingly phenocryst-poor (≤3%) with microphenocrysts of plagioclase and lesser pyroxene and olivine, which occasionally occur as crystal clots of ~1-3 mm instead of single crystals. In addition, minimal

The Disruption of Tephra Fall Deposits by Basaltic Lava Flows

Science.gov (United States)

Brown, R. J.; Thordarson, T.; Self, S.; Blake, S.

2010-12-01

Complex physical and stratigraphic relationships between lava and proximal tephra fall deposits around vents of the Roza Member in the Columbia River Basalt Province, (CRBP), USA, illustrate how basaltic lavas can disrupt, dissect (spatially and temporally) and alter tephra fall deposits. Thin pahoehoe lobes and sheet lobes occur intercalated with tephra deposits and provide evidence for synchronous effusive and explosive activity. Tephra that accumulated on the tops of inflating pahoehoe flows became disrupted by tumuli, which dissected the overlying sheet into a series of mounds. During inflation of subjacent tumuli tephra percolated down into the clefts and rubble at the top of the lava, and in some cases came into contact with lava hot enough to thermally alter it. Lava breakouts from the tumuli intruded up through the overlying tephra deposit and fed pahoehoe flows that spread across the surface of the aggrading tephra fall deposit. Non-welded scoria fall deposits were compacted and welded to a depth of ~50 cm underneath thick sheet lobes. These processes, deduced from the field relationships, have resulted in considerable stratigraphic complexity in proximal regions. We also demonstrate that, when the advance of lava and the fallout of tephra are synchronous, the contacts of some tephra sheets can be diachronous across their extent. The net effect is to reduce the usefulness of pyroclastic deposits in reconstructing eruption dynamics.

Radioisotopic determination methods of sulphur dispersion and sulphur blooming in rubber compounds

International Nuclear Information System (INIS)

Goraczka, W.; Koczorowska, E.

1997-01-01

It is well known that the concentration of sulphur in rubber compounds essentially effects the structure of the vulkanizate network. But there are no efficient and accurate methods to estimate the dispersion and migration (blooming) of curatives in raw rubber. In the work radioisotope methods have been analyzed to study the dispersion of curatives, physical and chemical processes in rubber and to optimize technical conditions of tire production. The radioactivity of the 35 S isotope introduced into rubber compounds has been measured by volumetric and surface methods. It was proved that the radioisotopic methods can be used in the studies. Experimental data of the effect of selected technological factors on these processes are presented. Rubber compounds containing soluble sulphur were made for such investigations. These methods permit detection of concentrations 10 -6 g of the radioactive isotope per 0.1 g of rubber compound. The sensitivity of these methods enables the investigation of radioisotope behaviour in rubber compounds during processing on an industrial scale without any hazards for workers

Determination of sulphur with total reflection x-ray spectrometry

International Nuclear Information System (INIS)

Steinmeyer, S.; Kolbesen, B.O.

2000-01-01

The potential and limitations of total reflection x-ray spectrometry (TXRF) were tested for the quantitative determination of the light element sulphur in inorganic and biological samples. As representatives of inorganic samples alkali, transition metal, magnesium and aluminum sulphates were investigated. As biological samples the sulphur containing amino acid methionine and the pharmaceutical drug insulin were chosen. All measurements were performed on a TXRF-spectrometer EXTRA IIA (Atomika Instruments, Oberschleissheim/Germany) using tungsten L-radiation as the excitation tube. Various concentrations of all samples ranging from 20 mg/l to 0.5 mg/l were determined. In addition the surface topography and thickness of the dry residue of these samples were investigated with SEM and a thickness profilometer (Alpha-Step). The result show that the reliable determination of sulphur in sulphates depends on the cation involved. Alkali sulphates like Na 2 SO 4 , or K 2 SO 4 form bulky residues resulting in significant deviations of the recovery rate of sulphur. In this case the use of smoothing detergents like 1 % HF, 1 % malic acid and 2 % hydrazinhydrat was found to be necessary for accurate determination. The results for the biological samples agree well with the expected values. The investigations lead to the conclusion that TXRF combined with a proper samples preparation is well suited for the determination of sulphur in different samples with various concentrations and matrices. (author)

Evolution of - and Core-Dominated Lava Flows Using Scaling Analysis

Science.gov (United States)

Castruccio, A.; Rust, A.; Sparks, R. S.

2010-12-01

We investigated the front evolution of simple lava flows on a slope using scaling arguments. For the retarding force acting against gravity, we analyzed three different cases: a flow controlled by a Newtonian viscosity, a flow controlled by the yield strength of a diffusively growing crust and a flow controlled by its core yield strength. These models were tested using previously published data of front evolution and volume discharge of 10 lava flow eruptions from 6 different volcanoes. Our analysis suggests that for basaltic eruptions with high effusion rate and low crystal content, (Hawaiian eruptions), the best fit of the data is with a Newtonian viscosity. For basaltic eruptions with lower effusion rates (Etna eruptions) or long duration andesitic eruptions (Lonquimay eruption, Chile) the flow is controlled by the yield strength of a growing crust. Finally, for very high crystalline lavas (Colima, Santiaguito) the flow is controlled by its core yield strength. The order of magnitude of the viscosities from our analysis is in the same range as previous studies using field measurements on the same lavas. The yield strength values for the growing crust and core of the flow are similar and with an order of magnitude of 10^5 Pa. This number is similar to yield strength values found in lava domes by different authors. The consistency of yield strength ~10^5 Pa is because larger stresses cause fracturing of very crystalline magma, which drastically reduces its effective strength. Furthermore, we used a 2-D analysis of a Bingham fluid flow on a slope to conclude that, for lower yield strength values, the flow is controlled mainly by its plastic viscosity and the lava can be effectively modelled as Newtonian. Our analysis provides a simple tool to evaluate the main controlling forces in the evolution of a lava flow, as well as the magnitude of its rheological properties, for eruptions of different compositions and conditions and may be useful to predict the evolution of

Polioencephalomalacia in ruminants caused by excessive amount of sulphur - a review

Directory of Open Access Journals (Sweden)

Lutnicki Krzysztof

2014-06-01

Full Text Available Polioencephalomalacia as a result of sulphur excess is a growing problem in cattle and sheep, mainly in young, growing animals. It is common in different regions of the world. The disease develops favoured by certain conditions such as sustained provision of feed and water with high sulphur content, use of dietary supplements containing sulphur, and a habitat with high hydrogen sulphide concentration. Pathogenesis of the disease is complex, but very important are oxidative-antioxidative imbalance, dysfunction of vessels, and secondary cerebral cortex ischaemia as a result of direct and/or indirect action of sulphur metabolites, namely hydrogen sulphide, sulphides, and sulphites. Clinical signs and changes in the cerebral cortex in the form of degenerative necrotic lesions are similar to those observed in polioencephalomalacia caused by vitamin B1 deficiency, and lead and salt intoxication. Highly increased sulphur content (more than 0.3-0.4 of dry matter in the diet is the basis for differential diagnosis, as well the high concentration of hydrogen sulphide in gas and sulphides in rumen fluid. In prophylaxis and treatment the most important measure is to limit sulphur intake and in acute cases to neutralise low pH in rumen and administer vitamin B1 injections.

Efficacy and phytotoicity of lime sulphur in organic apple production

NARCIS (Netherlands)

Holb, I.J.; Jong, de P.F.; Heijne, B.

2003-01-01

Curative and preventive efficacy and phytotoxicity of lime sulphur spray schedules, based on a warning system, were evaluated in the Netherlands during two growing seasons under field conditions. In most cases, lime sulphur treatments applied either curatively or preventively resulted in

Steam reforming of commercial ultra-low sulphur diesel

Energy Technology Data Exchange (ETDEWEB)

Boon, J.; Van Dijk, E.; De Munck, S.; Van den Brink, R. [Energy research Centre of The Netherlands, ECN Hydrogen and Clean Fossil Fuels, P.O. Box 1, NL1755ZG Petten (Netherlands)

2011-03-11

Two main routes for small-scale diesel steam reforming exist: low-temperature pre-reforming followed by well-established methane steam reforming on the one hand and direct steam reforming on the other hand. Tests with commercial catalysts and commercially obtained diesel fuels are presented for both processes. The fuels contained up to 6.5 ppmw sulphur and up to 4.5 vol.% of biomass-derived fatty acid methyl ester (FAME). Pre-reforming sulphur-free diesel at around 475C has been tested with a commercial nickel catalyst for 118 h without observing catalyst deactivation, at steam-to-carbon ratios as low as 2.6. Direct steam reforming at temperatures up to 800C has been tested with a commercial precious metal catalyst for a total of 1190 h with two catalyst batches at steam-to-carbon ratios as low as 2.5. Deactivation was neither observed with lower steam-to-carbon ratios nor for increasing sulphur concentration. The importance of good fuel evaporation and mixing for correct testing of catalysts is illustrated. Diesel containing biodiesel components resulted in poor spray quality, hence poor mixing and evaporation upstream, eventually causing decreasing catalyst performance. The feasibility of direct high temperature steam reforming of commercial low-sulphur diesel has been demonstrated.

Steam reforming of commercial ultra-low sulphur diesel

Science.gov (United States)

Boon, Jurriaan; van Dijk, Eric; de Munck, Sander; van den Brink, Ruud

Two main routes for small-scale diesel steam reforming exist: low-temperature pre-reforming followed by well-established methane steam reforming on the one hand and direct steam reforming on the other hand. Tests with commercial catalysts and commercially obtained diesel fuels are presented for both processes. The fuels contained up to 6.5 ppmw sulphur and up to 4.5 vol.% of biomass-derived fatty acid methyl ester (FAME). Pre-reforming sulphur-free diesel at around 475 °C has been tested with a commercial nickel catalyst for 118 h without observing catalyst deactivation, at steam-to-carbon ratios as low as 2.6. Direct steam reforming at temperatures up to 800 °C has been tested with a commercial precious metal catalyst for a total of 1190 h with two catalyst batches at steam-to-carbon ratios as low as 2.5. Deactivation was neither observed with lower steam-to-carbon ratios nor for increasing sulphur concentration. The importance of good fuel evaporation and mixing for correct testing of catalysts is illustrated. Diesel containing biodiesel components resulted in poor spray quality, hence poor mixing and evaporation upstream, eventually causing decreasing catalyst performance. The feasibility of direct high temperature steam reforming of commercial low-sulphur diesel has been demonstrated.

The implications of the new sulphur limits on the European Ro-Ro sector

DEFF Research Database (Denmark)

Zis, Thalis; Psaraftis, Harilaos N.

-based alternatives. The exact repercussions of the new sulphur limits are difficult to identify in the wake of significant recent reductions of the fuel prices for both low-sulphur and heavy fuel oil. This paper presents a modal split model that estimates modal shifts vis-a-vis competing maritime and land......In an effort to reduce the environmental impacts of maritime transportation, the International Maritime Organization (IMO) designated special Sulphur Emission ControlAreas (SECAs) where ships are required to use low-sulphur fuel. In January 2015, the sulphur limit within SECAs was lowered to 0.......1%, which can only be achieved if vessels are using pricier ultra-low sulphur fuel, or invest in abatement technologies. The increased operating costs borne by Ro-Ro operators in SECAs due to the stricter limits can result in the shutting down of some routes and a redistribution of cargo flows with land...

Sulphur-oxidising and Sulphate-reducing Communities in Brazilian Mangrove Sediments

NARCIS (Netherlands)

Varon-Lopez, Maryeimy; Dias, A.C.F; Fasanella, C.C.; Durrer, A.; Melo, I.S.; Kuramae, E.E.; Andreote, F.D.

2014-01-01

Mangrove soils are anaerobic environments rich in sulphate and organic matter. Although the sulphur cycle is one of the major actors in this ecosystem, little is known regarding the sulphur bacteria communities in mangrove soils. We investigated the abundance, composition and diversity of

Analogue experiments as benchmarks for models of lava flow emplacement

Science.gov (United States)

Garel, F.; Kaminski, E. C.; Tait, S.; Limare, A.

2013-12-01

During an effusive volcanic eruption, the crisis management is mainly based on the prediction of lava flow advance and its velocity. The spreading of a lava flow, seen as a gravity current, depends on its "effective rheology" and on the effusion rate. Fast-computing models have arisen in the past decade in order to predict in near real time lava flow path and rate of advance. This type of model, crucial to mitigate volcanic hazards and organize potential evacuation, has been mainly compared a posteriori to real cases of emplaced lava flows. The input parameters of such simulations applied to natural eruptions, especially effusion rate and topography, are often not known precisely, and are difficult to evaluate after the eruption. It is therefore not straightforward to identify the causes of discrepancies between model outputs and observed lava emplacement, whereas the comparison of models with controlled laboratory experiments appears easier. The challenge for numerical simulations of lava flow emplacement is to model the simultaneous advance and thermal structure of viscous lava flows. To provide original constraints later to be used in benchmark numerical simulations, we have performed lab-scale experiments investigating the cooling of isoviscous gravity currents. The simplest experimental set-up is as follows: silicone oil, whose viscosity, around 5 Pa.s, varies less than a factor of 2 in the temperature range studied, is injected from a point source onto a horizontal plate and spreads axisymmetrically. The oil is injected hot, and progressively cools down to ambient temperature away from the source. Once the flow is developed, it presents a stationary radial thermal structure whose characteristics depend on the input flow rate. In addition to the experimental observations, we have developed in Garel et al., JGR, 2012 a theoretical model confirming the relationship between supply rate, flow advance and stationary surface thermal structure. We also provide

The Influence of Topographic Obstacles on Basaltic Lava Flow Morphologies

Science.gov (United States)

von Meerscheidt, H. C.; Brand, B. D.; deWet, A. P.; Bleacher, J. E.; Hamilton, C. W.; Samuels, R.

2014-12-01

Smooth pāhoehoe and jagged ´áā represent two end-members of a textural spectrum that reflects the emplacement characteristics of basaltic lava flows. However, many additional textures (e.g., rubbly and slabby pāhoehoe) reflect a range of different process due to lava flow dynamics or interaction with topography. Unfortunately the influence of topography on the distribution of textures in basaltic lava flows is not well-understood. The 18 ± 1.0 ka Twin Craters lava flow in the Zuni-Bandera field (New Mexico, USA) provides an excellent site to study the morphological changes of a lava flow that encountered topographic obstacles. The flow field is 0.2-3.8 km wide with a prominent central tube system that intersects and wraps around a 1000 m long ridge, oriented perpendicular to flow. Upstream of the ridge, the flow has low-relief inflation features extending out and around the ridge. This area includes mildly to heavily disrupted pāhoehoe with interdispersed agglutinated masses, irregularly shaped rubble and lava balls. Breakouts of ´áā and collapse features are also common. These observations suggest crustal disruption due to flow-thickening upstream from the ridge and the movement of lava out and around the obstacle. While the ridge influenced the path of the tube, which wraps around the southern end of the ridge, the series of collapse features and breakouts of ´áā along the tube system are more likely a result of changes in flux throughout the tube system because these features are found both upstream and downstream of the obstacle. This work demonstrates that topography can significantly influence the formation history and surface disruption of a flow field, and in some cases the influence of topography can be separated from the influences of changes in flux along a tube system.

Lava inundation zone maps for Mauna Loa, Island of Hawaiʻi, Hawaii

Science.gov (United States)

Trusdell, Frank A.; Zoeller, Michael H.

2017-10-12

Lava flows from Mauna Loa volcano, on the Island of Hawaiʻi, constitute a significant hazard to people and property. This report addresses those lava flow hazards, mapping 18 potential lava inundation zones on the island.

Analytical protocols for the determination of sulphur compounds characteristic of the metabolism of Chlorobium limicola

Directory of Open Access Journals (Sweden)

A. Aliboni

2015-09-01

Full Text Available Chlorobium limicola belongs to the green sulphur bacteria that has a potential for technological applications such as biogas clean up oxidising hydrogen sulphide to elemental sulphur through photosynthetic process. In the present work, analytical methods are described for the determination of different sulphur species in C. limicola cultures – sulphide by GC-FPD, sulphate by ionic HPLC and elemental sulphur by RP HPLC. The latter method eliminates the need for chloroform extraction of water suspensions of elemental sulphur. Data from sulphide and elemental sulphur analyses have been compared with ones coming from more traditional analytical methodologies.

The genesis of a lava cave in the Deccan Volcanic Province (Maharashtra, India

Directory of Open Access Journals (Sweden)

Nikhil R. Pawar

2016-01-01

Full Text Available Lava tubes and channels forming lava distributaries have been recognized from different parts of western Deccan Volcanic Province (DVP. Openings of smaller dimension have been documented from the pāhoehoe flows around Pune, in the western DVP. A small lava cave is exposed in Ghoradeshwar hill, near Pune. Detailed field studies of the physical characteristics, structure and morphology of the flows hosting the lava tube has been carried out. This is the first detailed documentation of a lava cave from the DVP. The lava cave occurs in a compound pāhoehoe flow of Karla Formation, characterized by the presence of lobes, toes and small scale features like squeeze-ups. Field observations and measurements reveal that the dimensions of the cave are small, with low roof and a maximum width of 108 cm. The cave morphology along the 20 m passage varies from circular to semi-circular, with a twilight zone to the north. The gentle micro-topography at Ghoradeshwar controlled the advancement of pāhoehoe lobes and toes within the sheet lobe. The pre-flow gradients towards the north led to the progression of flow from the east, where the cave opening is presently seen. Dimensions and related morphology of the lava cave suggest that it can be best described as a small sub-crustal cave formed by draining of an inflated of pāhoehoe lava lobe. At Ghoradeshwar, besides the natural lava cave, Buddhist caves carved in pāhoehoe lava flows are also observed, indicating that early man took advantage of the existing openings in pāhoehoe flows and sculpted the caves to suit their requirements.

Assessing the suitability of Norway spruce wood as an environmental archive for sulphur

International Nuclear Information System (INIS)

Barrelet, T.; Ulrich, A.; Rennenberg, H.; Zwicky, C.N.; Kraehenbuehl, U.

2008-01-01

The aim of this study was to assess the suitability of Norway spruces (Picea abies L. Karst.) as an environmental archive for sulphur. For this purpose spruce trees were sampled in two distinct regions of Switzerland: the Alps and the Swiss Plateau, which differ significantly with respect to S immission. Wood samples were measured using two methods: LASER Ablation high resolution inductively coupled plasma mass spectrometry (LA-HR-ICP-MS) and inductively coupled plasma optical emission spectrometry (ICP-OES) after acid digestion. Independently corroborated by previous measurements of sulphur in peat bogs, the rise and fall of sulphur dioxide pollution in Switzerland appears to be reflected in spruce wood sulphur content. While the wood sulphur content profile of trees sampled in the Alps is relatively flat, the profiles of trees located on the Swiss Plateau display a characteristic sulphur peak. This corresponds to air pollution data in the different regions and indicates that the trees reacted on the changing S supply and recorded a pollution signal in the wood. - Norway spruce is a suitable archive for sulphur when physiological aspects and limitations are taken into account

Sulphur and lead isotopes in strata-bound deposits, ch. 8

International Nuclear Information System (INIS)

Sangster, D.F.

1976-01-01

The use of sulphur and lead isotopes as isotopic tracers in the study of ore deposits containing these elements is reviewed. A discussion of the general theory, including abundance and fractionation of sulphur isotopes, single-stage leads, and anomalous leads (two-stage) is given. Attention is paid to sulphur isotopes enclosed in deposits which are located in marine host rocks and in rocks of continental or near-continental origin, as well as in deposits of the conglomerate-U(-Au) type. The lead isotope content of volcanogenic massive sulphide deposits and carbonate-hosted lead-zinc deposits is discussed

Retrospective validation of a lava-flow hazard map for Mount Etna volcano

Directory of Open Access Journals (Sweden)

Ciro Del Negro

2011-12-01

Full Text Available This report presents a retrospective methodology to validate a long-term hazard map related to lava-flow invasion at Mount Etna, the most active volcano in Europe. A lava-flow hazard map provides the probability that a specific point will be affected by potential destructive volcanic processes over the time period considered. We constructed this lava-flow hazard map for Mount Etna volcano through the identification of the emission regions with the highest probabilities of eruptive vents and through characterization of the event types for the numerical simulations and the computation of the eruptive probabilities. Numerical simulations of lava-flow paths were carried out using the MAGFLOW cellular automata model. To validate the methodology developed, a hazard map was built by considering only the eruptions that occurred at Mount Etna before 1981. On the basis of the probability of coverage by lava flows, the map was divided into ten classes, and two fitting scores were calculated to measure the overlap between the hazard classes and the actual shapes of the lava flows that occurred after 1981.

Geochemistry of tholeiitic and alkalic lavas from the Koolau Range, Oahu, Hawaii

International Nuclear Information System (INIS)

Roden, M.F.; Frey, F.A.

1984-01-01

Lavas of the post-erosional, alkalic Honolulu Volcanics have significantly lower 87 Sr/ 86 Sr and higher 143 Nd/ 144 Nd than the older and underlying Koolau tholeiites which form the Koolau shield of eastern Oahu, Hawaii. Despite significant compositional variation within lavas forming the Honolulu Volcanics, these lavas are isotopically (Sr, Nd, Pb) very similar which contrasts with the isotopic heterogeneity of the Koolau tholeiites. Among Hawaiian tholeiitic suites, the Koolau lavas are geochemically distinct because of their lower iron contents and Sr and Nd isotopic ratios which range to bulk earth values. These geochemical data preclude simple models such as derivation of the Honolulu Volcanics and Koolau tholeiites from a common source by different degrees of melting or by mixing of two geochemically distinct sources. There may be no genetic relationship between the origin and evolution of these two lava suites; however, the trend shown by Koolau Range lavas of increasing 143 Nd/ 144 Nd and decreasing 87 Sr/ 86 Sr with decreasing eruption age and increasing alkalinity also occurs at Haleakala, East Molokai and Kauai volcaneoes. A complex mixing model proposed for Haleakala lavas can account for the variations in Sr and Nd isotopic ratios and processes occurring during ascent of relatively enriched mantle through relatively depleted MORB-related lithosphere. Although two isotopically distinct components may be sufficient to explain Sr and Nd isotopic variations at individual Hawaiian volcaneoes, more than two isotopically distinct materials are required to explain variations of Sr, Nd and Pb isotopic ratios in all Hawaiian lavas. (orig.)

33 CFR 117.331 - Snake Creek.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Snake Creek. 117.331 Section 117.331 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Florida § 117.331 Snake Creek. The draw of the Snake Creek...

Measurement of sulphur-35 in the coolant gas of the Windscale Advanced Gas-Cooled Reactor

International Nuclear Information System (INIS)

Sandalls, F.J.

1978-03-01

Sulphur is an important element in some food chains and the release of radioactive sulphur to the environment must be closely controlled if the chemical form is such that it is available or potentially available for entering food chains. The presence of sulphur-35 in the coolant gas of the Windscale Advanced Gas-Cooled Reactor warranted a study to assess the quantity and chemical form of the radioactive sulphur in order to estimate the magnitude of the potential environmental hazard which might arise from the release of coolant gas from Civil Advanced Gas-Cooled Reactors. A combination of gas chromatographic and radiochemical analyses revealed carbonyl sulphide to be the only sulphur-35 compound present in the coolant gas of the Windscale Reactor. The concentration of carbonyl sulphide was found to lie in the range 40 to 100 x 10 -9 parts by volume and the sulphur-35 specific activity was about 20 mCi per gramme. The analytical techniques are described in detail. The sulphur-35 appears to be derived from the sulphur and chlorine impurities in the graphite. A method for the preparation of carbonyl sulphide labelled with sulphur-35 is described. (author)

Mesoporous titanium-manganese dioxide for sulphur mustard and soman decontamination

International Nuclear Information System (INIS)

Stengl, Vaclav; Bludska, Jana; Oplustil, Frantisek; Nemec, Tomas

2011-01-01

Highlights: → New nano-dispersive materials for warfare agents decontamination. → 95% decontamination activities for sulphur mustard. → New materials base on titanium and manganese oxides. -- Abstract: Titanium(IV)-manganese(IV) nano-dispersed oxides were prepared by a homogeneous hydrolysis of potassium permanganate and titanium(IV) oxo-sulphate with 2-chloroacetamide. Synthesised samples were characterised using Brunauer-Emmett-Teller (BET) surface area and Barrett-Joiner-Halenda porosity (BJH), X-ray diffraction (XRD), infrared spectroscopy (IR), and scanning electron microscopy (SEM). These oxides were taken for an experimental evaluation of their reactivity with sulphur mustard (HD or bis(2-chloroethyl)sulphide) and soman (GD or (3,3'-dimethylbutan-2-yl)-methylphosphonofluoridate). Mn 4+ content affects the decontamination activity; with increasing Mn 4+ content the activity increases for sulphur mustard and decreases for soman. The best decontamination activities for sulphur mustard and soman were observed for samples TiMn 3 7 with 18.6 wt.% Mn and TiMn 5 with 2.1 wt.% Mn, respectively.

Erosion by flowing lava: Geochemical evidence in the Cave Basalt, Mount St. Helens, Washington

Science.gov (United States)

Williams, D.A.; Kadel, S.D.; Greeley, R.; Lesher, C.M.; Clynne, M.A.

2004-01-01

We sampled basaltic lava flows and underlying dacitic tuff deposits in or near lava tubes of the Cave Basalt, Mount St. Helens, Washington to determine whether the Cave Basalt lavas contain geochemical evidence of substrate contamination by lava erosion. The samples were analyzed using a combination of wavelength-dispersive X-ray fluorescence spectrometry and inductively-coupled plasma mass spectrometry. The results indicate that the oldest, outer lava tube linings in direct contact with the dacitic substrate are contaminated, whereas the younger, inner lava tube linings are uncontaminated and apparently either more evolved or enriched in residual liquid. The most heavily contaminated lavas occur closer to the vent and in steeper parts of the tube system, and the amount of contamination decreases with increasing distance downstream. These results suggest that erosion by lava and contamination were limited to only the initially emplaced flows and that erosion was localized and enhanced by vigorous laminar flow over steeper slopes. After cooling, the initial Cave Basalt lava flows formed an insulating lining within the tubes that prevented further erosion by later flows. This interpretation is consistent with models of lava erosion that predict higher erosion rates closer to sources and over steeper slopes. A greater abundance of xenoliths and xenocrysts relative to xenomelts in hand samples indicates that mechanical erosion rather than thermal erosion was the dominant erosional process in the Cave Basalt, but further sampling and petrographic analyses must be performed to verify this hypothesis. ?? Springer-Verlag 2003.

Henretta Creek reclamation project

International Nuclear Information System (INIS)

Pumphrey, J.F.

2009-01-01

Teck Coal Ltd. operates 6 open-pit coal mines, of which 5 are located in the Elk Valley in southeastern British Columbia. The Fording River Operations (FRO) began in 1971 in mining areas in Eagle Mountain, Turnbull Mountain and Henretta Valley. The recovery of approximately 5 million tons of coal from the Henretta Creek Valley posed significant challenges to mine planners, hydrologists and environmental experts because the coal had to be recovered from the valley flanks and also from under the main valley floor, on which the fish-bearing Henretta Creek runs. The Henretta Dragline Mining project was described along with the water control structures and fisheries management efforts for the cutthroat trout. A detailed Environmental Impact Assessment and Stage 1 mining report for the Henretta Valley area was completed in December 1990. FRO was granted a mining and reclamation permit in 1991. A temporary relocation of 1,270 metres was required in in April 1997 in order to enable mining on both sides and below the creek bed. Among the innovative construction techniques was a diversion of Henretta Creek through large diameter steel culverts and a specialized crossing of the creek to allow fish passage. The first water flowed through the reclaimed Henretta Creek channel in late 1998 and the first high flow occurred in the spring of 2000. Teck coal FRO then launched an annual fish and fish habitat monitoring program which focused on the Henretta Creek Reclaimed Channel and Henretta Lake. This document presented the results from the final year, 2006, and a summary of the 7 year aquatic monitoring program. It was concluded that from mining through to reclamation, the Henretta project shows the commitment and success of mining and reclamation practices at Teck Coal. Indicators of the project's success include riparian zone vegetation, fisheries re-establishment, aquatic communities and habitat utilization by terrestrial and avian species. 33 refs., 1 fig.

Rheology of arc dacite lavas: experimental determination at low strain rates

Science.gov (United States)

Avard, Geoffroy; Whittington, Alan G.

2012-07-01

Andesitic-dacitic volcanoes exhibit a large variety of eruption styles, including explosive eruptions, endogenous and exogenous dome growth, and kilometer-long lava flows. The rheology of these lavas can be investigated through field observations of flow and dome morphology, but this approach integrates the properties of lava over a wide range of temperatures. Another approach is through laboratory experiments; however, previous studies have used higher shear stresses and strain rates than are appropriate to lava flows. We measured the apparent viscosity of several lavas from Santiaguito and Bezymianny volcanoes by uniaxial compression, between 1,109 and 1,315 K, at low shear stress (0.085 to 0.42 MPa), low strain rate (between 1.1 × 10-8 and 1.9 × 10-5 s-1), and up to 43.7 % total deformation. The results show a strong variability of the apparent viscosity between different samples, which can be ascribed to differences in initial porosity and crystallinity. Deformation occurs primarily by compaction, with some cracking and/or vesicle coalescence. Our experiments yield apparent viscosities more than 1 order of magnitude lower than predicted by models based on experiments at higher strain rates. At lava flow conditions, no evidence of a yield strength is observed, and the apparent viscosity is best approached by a strain rate- and temperature-dependent power law equation. The best fit for Santiaguito lava, for temperatures between 1,164 and 1,226 K and strain rates lower than 1.8 × 10-4 s-1, is log {η_{{app}}} = - 0.738 + 9.24 × {10^3}{/}T(K) - 0.654 \\cdot log dot{\\varepsilon } where η app is apparent viscosity and dot{\\varepsilon } is strain rate. This equation also reproduced 45 data for a sample from Bezymianny with a root mean square deviation of 0.19 log unit Pa s. Applying the rheological model to lava flow conditions at Santiaguito yields calculated apparent viscosities that are in reasonable agreement with field observations and suggests that

Palæomagnetism of Hawaiian lava flows

Science.gov (United States)

Doell, Richard R.; Cox, Allan

1961-01-01

PALÆOMAGNETIC investigations of volcanic rocks extruded in various parts of the world during the past several million years have generally revealed a younger sequence of lava flows magnetized nearly parallel to the field of a theoretical geocentric axial dipole, underlain by a sequence of older flows with exactly the opposite direction of remanent magnetization. A 180-degree reversal of the geomagnetic field, occurring near the middle of the Pleistocene epoch, has been inferred by many workers from such results1–3. This is a preliminary report of an investigation of 755 oriented samples collected from 152 lava flows on the island of Hawaii, selected to represent as many stratigraphic horizons as possible. (Sampling details are indicated in Table 1.) This work was undertaken because Hawaii's numerous thick sequences of lava flows, previously mapped as Pliocene to Historic by Stearns and Macdonald4, and afterwards assigned ages ranging from later Tertiary to Recent, by Macdonald and Davis5, appeared to offer an ideal opportunity to examine the most recent reversal of Earth's field.

Interrogating trees for isotopic archives of atmospheric sulphur deposition and comparison to speleothem records

International Nuclear Information System (INIS)

Wynn, P.M.; Loader, N.J.; Fairchild, I.J.

2014-01-01

Palaeorecords which depict changes in sulphur dynamics form an invaluable resource for recording atmospheric pollution. Tree rings constitute an archive that are ubiquitously available and can be absolutely dated, providing the potential to explore local- to regional-scale trends in sulphur availability. Rapid isotopic analysis by a novel “on-line” method using elemental analyser isotope ratio mass spectrometry (EA-IRMS) is developed, achieving sample precision of <0.4‰ using sample sizes of 40 mg wood powder. Tree cores from NE Italy show trends in pollution, evidenced through increasing concentrations of sulphur towards the youngest growth, and inverse trends in sulphur isotopes differentiating modern growth with light sulphur isotopes (+0.7‰) from pre-industrial growth (+7.5‰) influenced by bedrock composition. Comparison with speleothem records from the same location demonstrate replication, albeit offset in isotopic value due to groundwater storage. Using EA-IRMS, tree ring archives form a valuable resource for understanding local- to regional-scale sulphur pollution dynamics. - Highlights: • Sulphur isotopes from tree rings are analysed using ‘on-line’ EA combustion. • Isotopes differentiate modern growth influenced by pollution from pre-industrial growth. • Biogeochemical cycling imparts minimal delay in sulphur incorporation into tree rings. • Trends in pollution are replicated between speleothems and trees from the same location. - Sulphur isotopes extracted from tree ring records are used to identify twentieth century pollution dynamics at the local- to regional-scale

Effect of Thiobacillus thioparus 1904 and sulphur addition on odour emission during aerobic composting.

Science.gov (United States)

Gu, Wenjie; Sun, Wen; Lu, Yusheng; Li, Xia; Xu, Peizhi; Xie, Kaizhi; Sun, Lili; Wu, Hangtao

2018-02-01

The effects of sulphur and Thiobacillus thioparus 1904 on odour emissions during composting were studied. Results indicated that the sulphur addition reduced the pH and decreased cumulative emission of ammonia and the nitrogen loss by 47.80% and 44.23%, respectively, but the amount of volatile sulphur compounds (VSCs) and the sulphur loss increased. The addition of T. thioparus 1904 effectively reduced the cumulative emissions of H 2 S, methyl sulphide, methanethiol, dimethyl disulphide and the sulphur loss by 33.24%, 81.24%, 32.70%, 54.22% and 54.24%, respectively. T. thioparus 1904 also limited the nitrogen loss. The combined application of sulphur and T. thioparus 1904 resulted in the greatest amount of nitrogen retention. The accumulation of ammonia emissions was reduced by 63.33%, and the nitrogen loss was reduced by 71.93%. The combined treatment did not increase the emission of VSCs. The application of sulphur and T. thioparus 1904 may help to control the odour of compost. Copyright © 2017. Published by Elsevier Ltd.

Channelized lava flows at the East Pacific Rise crest 9°-10°N: the importance of off-axis lava transport in developing the architecture of young oceanic crust

Science.gov (United States)

Soule, S.A.; Fornari, D.J.; Perfit, M.R.; Tivey, M.A.; Ridley, W.I.; Schouten, Hans

2005-01-01

 Submarine lava flows are the building blocks of young oceanic crust. Lava erupted at the ridge axis is transported across the ridge crest in a manner dictated by the rheology of the lava, the characteristics of the eruption, and the topography it encounters. The resulting lava flows can vary dramatically in form and consequently in their impact on the physical characteristics of the seafloor and the architecture of the upper 50–500 m of the oceanic crust. We have mapped and measured numerous submarine channelized lava flows at the East Pacific Rise (EPR) crest 9°–10°N that reflect the high-effusion-rate and high-flow-velocity end-member of lava eruption and transport at mid-ocean ridges. Channel systems composed of identifiable segments 50–1000 m in length extend up to 3 km from the axial summit trough (AST) and have widths of 10–50 m and depths of 2–3 m. Samples collected within the channels are N-MORB with Mg# indicating eruption from the AST. We produce detailed maps of lava surface morphology across the channel surface from mosaics of digital images that show lineated or flat sheets at the channel center bounded by brecciated lava at the channel margins. Modeled velocity profiles across the channel surface allow us to determine flux through the channels from 0.4 to 4.7 × 103m3/s, and modeled shear rates help explain the surface morphology variation. We suggest that channelized lava flows are a primary mechanism by which lava accumulates in the off-axis region (1–3 km) and produces the layer 2A thickening that is observed at fast and superfast spreading ridges. In addition, the rapid, high-volume-flux eruptions necessary to produce channelized flows may act as an indicator of the local magma budget along the EPR. We find that high concentrations of channelized lava flows correlate with local, across-axis ridge morphology indicative of an elevated magma budget. Additionally, in locations where channelized flows are located dominantly to the east

Sulphur in the Sculptor dwarf spheroidal galaxy. Including NLTE corrections

NARCIS (Netherlands)

Skúladóttir, Á.; Andrievsky, S. M.; Tolstoy, E.; Hill, V.; Salvadori, S.; Korotin, S. A.; Pettini, M.

In Galactic halo stars, sulphur has been shown to behave like other α-elements, but until now, no comprehensive studies have been done on this element in stars of other galaxies. Here, we use high-resolution ESO VLT/FLAMES/GIRAFFE spectra to determine sulphur abundances for 85 stars in the Sculptor

Sulphur in the metal poor globular cluster NGC 6397

Science.gov (United States)

Koch, A.; Caffau, E.

2011-10-01

Sulphur (S) is a non-refractory α-element that is not locked into dust grains in the interstellar medium. Thus no correction to the measured, interstellar sulphur abundance is needed and it can be readily compared to the S content in stellar photospheres. Here we present the first measurement of sulphur in the metal poor globular cluster (GC) NGC 6397, as detected in a MIKE/Magellan high signal-to-noise, high-resolution spectrum of one red giant star. While abundance ratios of sulphur are available for a larger number of Galactic stars down to an [Fe/H] of ~ -3.5 dex, no measurements in globular clusters more metal poor than -1.5 dex have been reported so far. We find aNLTE, 3-D abundance ratio of [S/Fe] = +0.52 ± 0.20 (stat.) ± 0.08 (sys.), based on theS I, Multiplet 1 line at 9212.8 Å. This value is consistent with a Galactic halo plateau as typical of other α-elements in GCs and field stars, but we cannot rule out its membership with a second branch of increasing [S/Fe] with decreasing [Fe/H], claimed in the literature, which leads to a large scatter at metallicities around - 2 dex. The [S/Mg] and [S/Ca] ratios in this star are compatible with a Solar value to within the (large) uncertainties. Despite the very large scatter in these ratios across Galactic stars between literature samples, this indicates that sulphur traces the chemical imprints of the other α-elements in metal poor GCs. Combined with its moderate sodium abundance ([S/Na]NLTE = 0.48), the [S/Fe] ratio in this GC extends a global, positive S-Na correlation that is not seen in field stars and might indicate that proton-capture reactions contributed to the production of sulphur in the (metal poor) early GC environments. This paper includes data gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, Chile.

Emplacement and erosive effects of the south Kasei Valles lava on Mars

Science.gov (United States)

Dundas, Colin M.; Keszthelyi, Laszlo P.

2014-01-01

Although it has generally been accepted that the Martian outflow channels were carved by floods of water, observations of large channels on Venus and Mercury demonstrate that lava flows can cause substantial erosion. Recent observations of large lava flows within outflow channels on Mars have revived discussion of the hypothesis that the Martian channels are also produced by lava. An excellent example is found in south Kasei Valles (SKV), where the most recent major event was emplacement of a large lava flow. Calculations using high-resolution Digital Terrain Models (DTMs) demonstrate that this flow was locally turbulent, similar to a previously described flood lava flow in Athabasca Valles. The modeled peak local flux of approximately 106 m3 s−1 was approximately an order of magnitude lower than that in Athabasca, which may be due to distance from the vent. Fluxes close to 107 m3 s−1 are estimated in some reaches but these values are probably records of local surges caused by a dam-breach event within the flow. The SKV lava was locally erosive and likely caused significant (kilometer-scale) headwall retreat at several cataracts with tens to hundreds of meters of relief. However, in other places the net effect of the flow was unambiguously aggradational, and these are more representative of most of the flow. The larger outflow channels have lengths of thousands of kilometers and incision of a kilometer or more. Therefore, lava flows comparable to the SKV flow did not carve the major Martian outflow channels, although the SKV flow was among the largest and highest-flux lava flows known in the Solar System.

Pore development in anodic alumina in sulphuric acid and borax electrolytes

International Nuclear Information System (INIS)

Garcia-Vergara, S.J.; Skeldon, P.; Thompson, G.E.; Habakaki, H.

2007-01-01

The formation of porous anodic films on an Al-3.5 at.%W alloy is compared in sulphuric acid and borax electrolytes in order to investigate pore development processes. The findings disclose that for anodizing in sulphuric acid, the pores develop mainly due to the influences of field-induced plasticity of the film and growth stresses; in borax, field-assisted dissolution dominates. The films formed in sulphuric acid are consequently much thicker than the layer of oxidized alloy and tungsten species are retained in the film. In contrast, with borax, the films and oxidized alloy layers are of similar thickness and tungsten species are lost to the electrolyte. Efficiencies of film growth are also significantly different, about 65% in sulphuric acid and about 52% in borax. The retention of tungsten species during anodizing in sulphuric acid is due to the localization of tungsten in the inner regions of the barrier layer and cell walls, with a layer of anodic alumina separating the tungsten-containing regions from the electrolyte. For borax, the tungsten is distributed more uniformly through the film material, enabling loss of tungsten species to the electrolyte from the pore base

Textural and rheological evolution of basalt flowing down a lava channel

Science.gov (United States)

Robert, Bénédicte; Harris, Andrew; Gurioli, Lucia; Médard, Etienne; Sehlke, Alexander; Whittington, Alan

2014-06-01

The Muliwai a Pele lava channel was emplaced during the final stage of Mauna Ulu's 1969-1974 eruption (Kilauea, Hawaii). The event was fountain-fed and lasted for around 50 h, during which time a channelized flow system developed, in which a 6-km channel fed a zone of dispersed flow that extended a further 2.6 km. The channel was surrounded by initial rubble levees of 'a'a, capped by overflow units of limited extent. We sampled the uppermost overflow unit every 250 m down the entire channel length, collecting, and analyzing 27 air-quenched samples. Bulk chemistry, density and textural analyses were carried out on the sample interior, and glass chemistry and microlite crystallization analyses were completed on the quenched crust. Thermal and rheological parameters (cooling, crystallization rate, viscosity, and yield strength) were also calculated. Results show that all parameters experience a change around 4.5 km from the vent. At this point, there is a lava surface transition from pahoehoe to 'a'a. Lava density, microlite content, viscosity, and yield strength all increase down channel, but vesicle content and lava temperature decrease. Cooling rates were 6.7 °C/km, with crystallization rates increasing from 0.03 Фc/km proximally, to 0.14 Фc/km distally. Modeling of the channel was carried out using the FLOWGO thermo-rheological model and allowed fits for temperature, microlite content, and channel width when run using a three-phase viscosity model based on a temperature-dependent viscosity relation derived for this lava. The down flow velocity profile suggests an initial velocity of 27 m/s, declining to 1 m/s at the end of the channel. Down-channel, lava underwent cooling that induced crystallization, causing both the lava viscosity and yield strength to increase. Moreover, lava underwent degassing and a subsequent vesicularity decrease. This aided in increasing viscosity, with the subsequent increase in shearing promoting a transition to 'a'a.

Natural-Scale Lava Flow Experiments on Video: Variations with Temperature, Slope, and Effusion Rate

Science.gov (United States)

Karson, J. A.; Wysocki, R.; Edwards, B. R.; Lev, E.

2013-12-01

Investigations of active basaltic lava flows and analog materials show that flow dynamics and final flow morphology are strongly determined by the rapidly evolving rheology of the lava crust which constrains the downslope advance of the lava flow. The non-dimensional factor Ψ (ratio of the time scale of crust formation to advective heat loss) provides a useful means of comparing different flows. The key parameters that control Ψ include the melt viscosity, temperature, effusion rate, and slope. Experimental lava flows, up to several meters long created in the Syracuse University Lava Project permit these variables to be investigated independently and in combination in volume-limited flows (Pele), that provide additional information on lava crust development. New, continuous flow (cooling-limited) experiments show downslope variations under constant flow conditions.

Distribution of sulphur and trace elements in peat. [Literature survey with some additional sulphur analyses

Energy Technology Data Exchange (ETDEWEB)

Huttunen, S; Karhu, M

1981-01-01

A survey on the literature and contemporary research was made on peat sulphur and trace element studies. Marked variance between different peatlands and peat types has been noted. The available information is still inadequate for generalizations or statistical analysis mainly due to methodological variations and temporal and spatial variations in results. At the moment, the criteria applied in peatland inventories and evaluations are inadequate with respect to peat quality determinations. To some extent the quality of fuel peat should be determined in a mire inventory prior to peatland utilization. The areas over sulphide clay and some sulphate depositions may considerably increase the peat sulphur content. A proposal has been made to include the sulphur content monitoring in the cases where it exceeds 0.3 per cent. The trace elements may also bring about an increase in peat emissions if the deepest peat layers or polluted layers are burnt. The most important elements in this respect are Al, Fe, Mn, Pb, Zn, V, Ni, Hg, Cu, Cr, as well as As and U. The first ten because of the relatively high concentrations and last two because of pollution or toxocity and ore deposit factors. The peat hydrogen ion concentration has a positive correlation with copper and vanadium. The correlation is positive with the cobalt and nickel contents when the pH is low, and negative at a higher pH. A general peat type correlation shows maximum trace element contents in basal Carex peats with subsoil effects. The peat ash content and the Ti, Pb, V, Cr, Ni and S contents have positive correlations.

Selected caves and lava-tube systems in and near Lava Beds National Monument, California

Science.gov (United States)

Waters, Aaron Clement; Donnelly-Nolan, Julie M.; Rogers, Bruce W.

1990-01-01

Lava Beds National Monument (fig. 1) lies on the north slope of the huge Medicine Lake shield (fig. 2), a complex volcanic edifice of greater volume than the steep-sided Mount Shasta volcanic cone, which towers as a snowclad land mark 40 mi southwest of the monument (fig. 3).

Sulphur loading of respirable and inhalable dust at a platinum smelter / Swanepoel J.D.

OpenAIRE

Swanepoel, Johannes Deon.

2012-01-01

The contribution that sulphur, in the form of sulphates, has on ill health is still a focal point of many a study, especially in environmental studies depicting the effects that particulate air pollution has on health. Although the implication of sulphur on particulate matter is not yet well defined, numerous studies do state that the presence of sulphur on particulate matter contributes to poor health. Sulphur adhered to dust has been associated with cardiovascular mortality and the ability ...

An isotope view on ionising radiation as a source of sulphuric acid

DEFF Research Database (Denmark)

Enghoff, Martin Andreas Bødker; Bork, Nicolai Christian; Hattori, S.

2012-01-01

Sulphuric acid is an important factor in aerosol nucleation and growth. It has been shown that ions enhance the formation of sulphuric acid aerosols, but the exact mechanism has remained undetermined. Furthermore some studies have found a deficiency in the sulphuric acid budget, suggesting a miss...... yields of the experiments, suggests a mechanism in which ionising radiation may lead to hydrated ion clusters that serve as nanoreactors for S(IV) to S(VI) conversion....

An isotopic analysis of ionising radiation as a source of sulphuric acid

DEFF Research Database (Denmark)

Enghoff, Martin Andreas Bødker; Bork, Nicolai Christian; Hattori, S.

2012-01-01

Sulphuric acid is an important factor in aerosol nucleation and growth. It has been shown that ions enhance the formation of sulphuric acid aerosols, but the exact mechanism has remained undetermined. Furthermore some studies have found a deficiency in the sulphuric acid budget, suggesting a miss...... of the experiments, suggests a mechanism in which ionising radiation may lead to hydrated ion clusters that serve as nanoreactors for S(IV) to S(VI) conversion....

Eruptive history, geochronology, and post-eruption structural evolution of the late Eocene Hall Creek Caldera, Toiyabe Range, Nevada

Science.gov (United States)

Colgan, Joseph P.; Henry, Christopher D.

2017-02-24

The magmatic, tectonic, and topographic evolution of what is now the northern Great Basin remains controversial, notably the temporal and spatial relation between magmatism and extensional faulting. This controversy is exemplified in the northern Toiyabe Range of central Nevada, where previous geologic mapping suggested the presence of a caldera that sourced the late Eocene (34.0 mega-annum [Ma]) tuff of Hall Creek. This region was also inferred to be the locus of large-magnitude middle Tertiary extension (more than 100 percent strain) localized along the Bernd Canyon detachment fault, and to be the approximate location of a middle Tertiary paleodivide that separated east and west-draining paleovalleys. Geologic mapping, 40Ar/39Ar dating, and geochemical analyses document the geologic history and extent of the Hall Creek caldera, define the regional paleotopography at the time it formed, and clarify the timing and kinematics of post-caldera extensional faulting. During and after late Eocene volcanism, the northern Toiyabe Range was characterized by an east-west trending ridge in the area of present-day Mount Callaghan, probably localized along a Mesozoic anticline. Andesite lava flows erupted around 35–34 Ma ponded hundreds of meters thick in the erosional low areas surrounding this structural high, particularly in the Simpson Park Mountains. The Hall Creek caldera formed ca. 34.0 Ma during eruption of the approximately 400 cubic kilometers (km3) tuff of Hall Creek, a moderately crystal-rich rhyolite (71–77 percent SiO2) ash-flow tuff. Caldera collapse was piston-like with an intact floor block, and the caldera filled with thick (approximately 2,600 meters) intracaldera tuff and interbedded breccia lenses shed from the caldera walls. The most extensive exposed megabreccia deposits are concentrated on or close to the caldera floor in the southwestern part of the caldera. Both silicic and intermediate post-caldera lavas were locally erupted within 400 thousand

Muonium states and dynamics in phosphorus and sulphur

International Nuclear Information System (INIS)

Cox, S.F.J.; Cottrell, S.P.; Hopkins, G.A.; Kay, M.; Pratt, F.L.

1997-01-01

The various states formed by positive muons implanted into phosphorus and sulphur have been characterized as a model for interstitial hydrogen, of which little is known in these elements. Repolarization studies reveal muonium-like states in each case, giving estimates of the hyperfine parameters and, for sulphur at least, an indication of the coexistence of a molecular radical state. The longitudinal-field relaxation functions suggest conversion of the paramagnetic states to diamagnetic, i.e. ionization or chemical reaction, in competition with strong spin-lattice relaxation

Geochronology and geochemistry of lavas from the 1996 North Gorda Ridge eruption

Science.gov (United States)

Rubin, K. H.; Smith, M. C.; Perfit, M. R.; Christie, D. M.; Sacks, L. F.

1998-12-01

Radiometric dating of three North Gorda Ridge lavas by the 210Po- 210Pb method confirms that an eruption occurred during a period of increased seismic activity along the ridge during late February/early March 1996. These lavas were collected following detection of enhanced T-phase seismicity and subsequent ocean bottom photographs documented the existence of a large pillow mound of fresh-appearing lavas. 210Po- 210Pb dating of these lavas indicates that an eruption coinciding with this seismicity did occur (within analytical error) and that followup efforts to sample the recent lava flows were successful. Compositions of the three confirmed young lavas and eleven other samples of this contiguous "new flow" sequence are distinct from older lavas from this area but are variable at a level outside analytical uncertainty. These intraflow variations can not easily be related to a single, common parent magma. Compositional variability within the new flow is compared to that of other recently documented individual flow sequences, and this comparison reveals a strong positive correlation of compositional variance with flow volumes spanning a range of >2 orders of magnitude. The geochemical heterogeneity in the North Gorda new flow probably reflects incomplete mixing of magmas generated from a heterogeneous mantle source or from slightly different melting conditions of a single source. The compositional variability, range in sample ages (up to 6 weeks) and range in active seismicity (4 weeks) imply that this relatively large flow was erupted over an interval of several weeks.

Sulphur levels in saliva as an estimation of sulphur status in cattle: a validation study

NARCIS (Netherlands)

Dermauw, V.; Froidmont, E.; Dijkstra, J.; Boever, de J.L.; Vyverman, W.; Debeer, A.E.; Janssens, G.P.J.

2012-01-01

Effective assessment of sulphur (S) status in cattle is important for optimal health, yet remains difficult. Rumen fluid S concentrations are preferred, but difficult to sample under practical conditions. This study aimed to evaluate salivary S concentration as estimator of S status in cattle.

Comparative study on sulphur reduction from heavy petroleum - Solvent extraction and microwave irradiation approach

Energy Technology Data Exchange (ETDEWEB)

Mohammed, Abdullahi Dyadya; Isah, Abubakar Garba; Umaru, Musa; Ahmed, Shehu [Department of Chemical Engineering, Federal University of Technology, P.M.B 65, Minna (Nigeria); Abdullahi, Yababa Nma [National Petroleum Investment Management Services (Nigeria National Petroleum Corporation), Lagos (Nigeria)

2012-07-01

Sulphur- containing compounds in heavy crude oils are undesirable in refining process as they affect the quality of the final product, cause catalyst poisoning and deactivation in catalytic converters as well as causing corrosion problems in oil pipelines, pumps and refining equipment aside environmental pollution from their combustion and high processing cost. Sulphur reduction has being studied using microwave irradiation set at 300W for 10 and 15minutes and oxidative- solvent extraction method using n- heptane and methanol by 1:1, 1:2 and 1:3 crude- solvent ratios after being oxidized with hydrogen peroxide, H2O2 oxidants. Percentage sulphur removal with n- heptane solvent by 1:1 and 1:2 are 81.73 and 85.47%; but extraction using methanol by different observed ratios gave less sulphur reduction. Indeed when microwave irradiated at 300W for 10 and 15minutes, 53.68 and 78.45% reduction were achieved. This indicates that microwave irradiation had caused oxidation by air in the oven cavity and results to formation of alkyl radicals and sulphoxide from sulphur compound in the petroleum. The prevailing sulphur found in the crude going by FT-IR results is sulphides which oxidized to sulphoxide or sulphones. It is clear that sulphur extraction with heptane is more efficient than microwave irradiation but economically due to demands for solvent and its industrial usage microwave irradiation can serve as alternative substitute for sulphur reduction in petroleum. Sulphur reduction by microwave radiation should be up- scaled from laboratory to a pilot plant without involving extraction column in the refining.

Lava flooding of ancient planetary crusts: geometry, thickness, and volumes of flooded lunar impact basins

International Nuclear Information System (INIS)

Head, J.W.

1982-01-01

Estimates of lava volumes on planetary surfaces provide important data on the lava flooding history and thermal evolution of a planet. Lack of information concerning the configuration of the topography prior to volcanic flooding requires the use of a variety of techniques to estimate lava thicknesses and volumes. A technique is described and developed which provides volume estimates by artificially flooding unflooded lunar topography characteristic of certain geological environments, and tracking the area covered, lava thicknesses, and lava volumes. Comparisons of map patterns of incompletely buried topography in these artificially flooded areas are then made to lava-flooded topography on the Moon in order to estimate the actual lava volumes. This technique is applied to two areas related to lunar impact basins; the relatively unflooded Orientale basin, and the Archimedes-Apennine Bench region of the Imbrium basin. (Auth.)

78 FR 64526 - Information Collection Activities: Sulphur Operations; Submitted for Office of Management and...

Science.gov (United States)

2013-10-29

...: Sulphur Operations; Submitted for Office of Management and Budget (OMB) Review; Comment Request ACTION: 30... paperwork requirements in the regulations under Subpart P, Sulphur Operations. This notice also provides the..., Currently Under Review). SUPPLEMENTARY INFORMATION: Title: 30 CFR 250, Subpart P, Sulphur Operations. OMB...

An analytical procedure for determination of sulphur species and isotopes in boreal acid sulphate soils and sediments

Directory of Open Access Journals (Sweden)

K. BACKLUND

2008-12-01

Full Text Available An analytical scheme suitable for boreal acid sulphate (AS soils and sediments was developed on the basis of existing methods. The presented procedure can be used to quantify and discriminate among acid volatile sulphide, cold chromium reducible sulphur, hot chromium reducible sulphur, elemental sulphur, sulphate sulphur, organic sulphur, total reducible sulphur and total sulphur. The sulphur fractions are recovered as either Ag2S or BaSO4 precipitates and can further be used for isotope analysis. Overlaps between sulphur species are common during speciation, and must be minimized. Some of these overlaps are caused by poor sampling and storage, inappropriate conditions during the distillation, or natural variations in the sample (e.g. Fe3+ interference and grain size. The procedural impact was determined by conducting tests on both artificial and natural samples containing one or several sulphur species. The method is applied on reduced sediment from an AS soil locality (Överpurmo and a brackish lake (Larsmo Lake in western Finland and the results, including S-isotopes, are discussed.;

Ball-milling synthesis of ZnO@sulphur/carbon nanotubes and Ni(OH)_2@sulphur/carbon nanotubes composites for high-performance lithium-sulphur batteries

International Nuclear Information System (INIS)

Gu, Xingxing; Tong, Chuan-jia; Wen, Bo; Liu, Li-min; Lai, Chao; Zhang, Shanqing

2016-01-01

Highlights: • Metal oxides or hydroxides coating sulfur-based composite are successfully prepared. • Large-scale synthesis can be realized via the facile wet ball-milling strategy. • Density functional theory (DFT) calculation is applied to calculate adsorption energy. • ZnO exhibits a higher adsorption energy for Li_2S_8 than that Ni(OH)_2. • ZnO@sulphur/carbon nanotubes composite show excellent cycle and discharge performance. - Abstract: Zinc oxide wrapped sulphur/carbon nanotubes (ZnO@S/CNT) and nickel hydroxide wrapped sulphur/carbon nanotubes (Ni(OH)_2@S/CNT) nanocomposites are prepared using a simple, low cost and scalable ball-milling method. As the cathodes in Li-S batteries, the as-prepared ZnO@S/CNT composite illustrates a superior high initial capacity of 1663 mAh g"−"1 at a charge/discharge rate of 160 mA g"−"1, and maintains a reversible capacity at approximately 942 mAh g"−"1 after 70 cycles. While for Ni(OH)_2@S/CNT composites, its initial capacity is also as high as 1331 mAh g"−"1, but a poorer cycling stability is presented. When the charge/discharge current is increased to 1600 mA g"−"1, a high reversible capacity of 698 mAh g"−"1 after 200 cycles still can be obtained for the ZnO@S/CNT composite, far better than that of Ni(OH)_2@S/CNT composites. The better cycling performance and high discharge capacity can be attributed to the strong interactions between ZnO and S_x"2"− species, which is verified by the density functional theory (DFT) calculation result that the ZnO exhibits a higher adsorption energy for Li_2S_8 than the Ni(OH)_2.

Mesoporous titanium-manganese dioxide for sulphur mustard and soman decontamination

Energy Technology Data Exchange (ETDEWEB)

Stengl, Vaclav, E-mail: stengl@iic.cas.cz [Department of Solid State Chemistry, Institute of Inorganic Chemistry AS CR v.v.i., 250 68 Rez (Czech Republic); Bludska, Jana [Department of Solid State Chemistry, Institute of Inorganic Chemistry AS CR v.v.i., 250 68 Rez (Czech Republic); Oplustil, Frantisek; Nemec, Tomas [Military Technical Institute of Protection Brno, Veslarska 230, 628 00 Brno (Czech Republic)

2011-11-15

Highlights: {yields} New nano-dispersive materials for warfare agents decontamination. {yields} 95% decontamination activities for sulphur mustard. {yields} New materials base on titanium and manganese oxides. -- Abstract: Titanium(IV)-manganese(IV) nano-dispersed oxides were prepared by a homogeneous hydrolysis of potassium permanganate and titanium(IV) oxo-sulphate with 2-chloroacetamide. Synthesised samples were characterised using Brunauer-Emmett-Teller (BET) surface area and Barrett-Joiner-Halenda porosity (BJH), X-ray diffraction (XRD), infrared spectroscopy (IR), and scanning electron microscopy (SEM). These oxides were taken for an experimental evaluation of their reactivity with sulphur mustard (HD or bis(2-chloroethyl)sulphide) and soman (GD or (3,3'-dimethylbutan-2-yl)-methylphosphonofluoridate). Mn{sup 4+} content affects the decontamination activity; with increasing Mn{sup 4+} content the activity increases for sulphur mustard and decreases for soman. The best decontamination activities for sulphur mustard and soman were observed for samples TiMn{sub 3}7 with 18.6 wt.% Mn and TiMn{sub 5} with 2.1 wt.% Mn, respectively.

75 FR 32357 - Gallatin National Forest; Montana; Jack Rabbit to Big Sky Meadow Village 161 kV Transmission Line...

Science.gov (United States)

2010-06-08

... prior to the close of the comment period and should clearly articulate the reviewer's concerns and... during the scoping of the proposed action and the comment period. The decision maker will take into... near Cascade Creek homes/Lava Lake Trailhead area, Greek Creek homes and the Deer Creek Trailhead areas...

Geomagnetic polarity zones for icelandic lavas

Science.gov (United States)

Dagley, P.; Wilson, R.L.; Ade-Hall, J. M.; Walker, G.P.L.; Haggerty, S.E.; Sigurgeirsson, T.; Watkins, N.D.; Smith, P.J.; Edwards, J.; Grasty, R.L.

1967-01-01

Analysis of cores collected from a sequence of lavas in Eastern Iceland has made possible an accurate calculation of the average rate of reversal of the Earth's magnetic field. ?? 1967 Nature Publishing Group.

THE SOLUBILITY OF MILAS BAUXITE ORE IN SULPHURIC ACI

Directory of Open Access Journals (Sweden)

Mustafa GULFEN

2001-06-01

Full Text Available The effects of calcination conditions,sulphuric acid concentrations and dissolvingtemperature and period as parameters to thesolubility of the bauxite ore from Gobekdagı reservesin Mugla-Milas region were investigated. The bauxitesamples were calcined in different periods at differenttemperatures. Then the solubility of the calcinedbauxite samples in sulphuric acid solution wasexamined. Dissolving activation energy (Ea wascalculated using the optimum kinetics equation andthe results obtained from the solubility studiesexamined dissolving temperatures and periods

Leaching of basic oxygen furnace sludge with sulphuric acid

Directory of Open Access Journals (Sweden)

Andrea Miškufová

2010-03-01

Full Text Available In this study the hydrometallurgical processing of BOF sludge in the sulphuric acid solutions under atmospheric pressureand temperatures up to 100 °C is investigated on a laboratory scale. The influence of sulphuric acid concentration, temperature, timeand liquid to solid ratio (L:S on the leaching process was studied. The main aim of this study was to determine optimal conditions whenthe maximum amount of zinc passes into the solution.

Morphologic and thermophysical characteristics of lava flows southwest of Arsia Mons, Mars

Science.gov (United States)

Crown, David A.; Ramsey, Michael S.

2017-08-01

The morphologic and thermophysical characteristics of part of the extensive lava flow fields southwest of Arsia Mons (22.5-27.5°S, 120-130°W) have been examined using a combination of orbital VNIR and TIR datasets. THEMIS images provide context for the regional geology and record diurnal temperature variability that is diverse and unusual for flow surfaces in such close proximity. CTX images were used to distinguish dominant flow types and assess local age relationships between individual lava flows. CTX and HiRISE images provide detailed information on flow surface textures and document aeolian effects as they reveal fine-grained deposits in many low-lying areas of the flow surfaces as well as small patches of transverse aeolian ridges. Although this region is generally dust-covered and has a lower overall thermal inertia, the THEMIS data indicate subtle spectral variations within the population of lava flows studied. These variations could be due to compositional differences among the flows or related to mixing of flow and aeolian materials. Specific results regarding flow morphology include: a) Two main lava flow types (bright, rugged and dark, smooth as observed in CTX images) dominate the southwest Arsia Mons/NE Daedalia Planum region; b) the bright, rugged flows have knobby, ridged, and/or platy surface textures, commonly have medial channel/levee systems, and may have broad distal lobes; c) the dark, smooth flows extend from distributary systems that consist of combinations of lava channels, lava tubes, and/or sinuous ridges and plateaus; and d) steep-sided, terraced margins, digitate breakout lobes, and smooth-surfaced plateaus along lava channel/tube systems are interpreted as signatures of flow inflation within the dark, smooth flow type. These flows exhibit smoother upper surfaces, are thinner, and have more numerous, smaller lobes, which, along with their the channel-/tube-fed nature, indicate a lower viscosity lava than for the bright, rugged flows

Regional modelling of anthropogenic sulphur in Southeast Asia

Science.gov (United States)

Engardt, M.; Leong, C. P.

A co-operative research project between the Malaysian Meteorological Service (MMS) and the Swedish Meteorological and Hydrological Institute (SMHI) focussing on the usage of an atmospheric transport and chemistry model, has just been initiated. Here, we describe the main features of the dispersion model and discuss a first set of calculations in light of available measurements of sulphuric species in Southeast Asia. According to our results, anthropogenic sulphur concentrations and depositions are particularly high near the large cities of the region, around a metal smelter in the southern Philippines, and in a region extending from northern Vietnam into southeastern China. These areas coincide with the high-emissions regions of Southeast Asia and we tentatively conclude that regional transport of acidifying species is not as far-reaching as in the mid-latitudes. From our calculations, and from supporting measurements we conclude that most of rural Southeast Asia is not yet severely affected by anthropogenic sulphur, but given the rapid rate of economical development in this region the situation may deteriorate quickly. Areas that are particularly at risk include the large cities, northern Vietnam, most of central Thailand, most of peninsular Malaysia, eastern Sumatra and parts of Java, all of which receive total-sulphur depositions in excess of 0.5 g S m -2 yr -1. Our model simulates sulphate in precipitation in accordance with measurements, but it has a tendency to overestimate atmospheric SO 2. It remains to be investigated whether this is a problem in the model formulation or a result of unrepresentative sampling. An immediate continuation of this study should be performed with higher spatial resolution than the currently used 100×100 km 2. Other imperfections in this model study, which should be addressed in future work, include parameterised vertical transport in deep convective clouds, the influence of natural emissions (primarily from volcanoes) on the

Submarine Rejuvenated-Stage Lavas Offshore Molokai, Oahu, Kauai, and Niihau, Hawaii

Science.gov (United States)

Clague, D. A.; Cousens, B. L.; Davis, A. S.; Dixon, J. E.; Hon, K.; Moore, J. G.; Reynolds, J. R.

2003-12-01

Rejuvenated-stage lavas from the Hawaiian Islands form many distinctive landmarks, such as Diamond Head. They have been relatively well studied due to their primitive, strongly alkaline compositions (alkalic basalt, basanite, nephelinite, melilitite, phonolite). More recently, compositionally similar lavas have been mapped and sampled on the deep seafloor around the islands. Rejuvenated-stage cones also occur on the submarine flanks of the islands. A Pisces V submersible dive collected samples from the only submarine cone on the north slope of East Molokai. The alkalic basalt to basanite composition lava is similar to the subaerial Kalaupapa basalt (Clague and Moore, 2003). MBARI Tiburon ROV dives recovered nephelinite from a lone steep cone on the northeast slope of Oahu, alkalic basalt from two shallow steep cones just west of the Koko Rift, and alkalic basalt from the submarine flank of Diamond Head on Oahu's south flank. These lavas are generally similar to subaerial Honolulu Volcanics, although the isotopic data extend to higher Sr isotopic values. Other MBARI Tiburon ROV dives recovered alkalic basalt and basanite from 8 separate steep cones on the south flank of Kauai. Once again, these lavas are chemically similar to those from the subaerial Koloa Volcanics. Samples from one of these cones contained common xenoliths of upper mantle lherzolite and harzburgite. Seven MBARI Tiburon ROV dives on the northwest flank of Niihau sampled 6 flat-topped cones and 5 pointed cones. The lavas from the flat-topped cones are alkalic basalt similar to rejuvenated Kiekie Basalt on Niihau Island whereas the lavas from the pointed cones are basanite, hawaiite, and tephrophonolite that are chemically distinct from the Kiekie Basalt, but similar to rejuvenated-stage lavas on Kauai and Oahu. Volcaniclastic deposits were observed and sampled at many of the sites offshore Niihau, Kauai, and Oahu, as well as the North Arch. Breadcrust and spindle bombs and spatter were found

Formation processes of the 1909 Tarumai and the 1944 Usu lava domesin Hokkaido, Japan

Directory of Open Access Journals (Sweden)

I. Yokoyama

2004-06-01

Full Text Available The formation of the two particular lava domes in Hokkaido, Japan is described and interpreted mainly from geophysical viewpoints. The 1909 eruption of Tarumai volcano was not violent but produced a lava dome over four days. The growth rate of the dome is discussed under the assumption that the lava flow was viscous and plastic fluid during its effusion. By Hagen-Poiseuille?s Law, the length of the conduit of the lava dome is rather ambiguously determined as a function of viscosity of the magma and diameter of the conduit. The 1944 Usu dome extruded as a parasitic cone of Usu volcano, not in the crater, but in a flat cornfield at the foot of the volcano. From the beginning to the end for more than 17 months, seismometric and geodetic observations of the dome activity were carried out by several pioneering geophysicists. Utilizing their data, pseudo growth curves of the dome at each stage can be drawn. The lava ascended rather uniformly, causing uplift of the ground surface until half-solidified lava reached the surface six months after the deformation began. Thereafter, the lava dome added lateral displacements and finally achieved its onion structure. These two lava domes are of contrasting character, one is andesitic and formed quickly while the other is dacitic and formed slowly, but both of them behaved as viscous and plastic flows during effusion. It is concluded that both the lava domes formed by uplift of magma forced to flow through the conduits, analogous to squeezing toothpaste out of a tube.

Hydrology of the Johnson Creek Basin, Oregon

Science.gov (United States)

Lee, Karl K.; Snyder, Daniel T.

2009-01-01

The Johnson Creek basin is an important resource in the Portland, Oregon, metropolitan area. Johnson Creek forms a wildlife and recreational corridor through densely populated areas of the cities of Milwaukie, Portland, and Gresham, and rural and agricultural areas of Multnomah and Clackamas Counties. The basin has changed as a result of agricultural and urban development, stream channelization, and construction of roads, drains, and other features characteristic of human occupation. Flooding of Johnson Creek is a concern for the public and for water management officials. The interaction of the groundwater and surface-water systems in the Johnson Creek basin also is important. The occurrence of flooding from high groundwater discharge and from a rising water table prompted this study. As the Portland metropolitan area continues to grow, human-induced effects on streams in the Johnson Creek basin will continue. This report provides information on the groundwater and surface-water systems over a range of hydrologic conditions, as well as the interaction these of systems, and will aid in management of water resources in the area. High and low flows of Crystal Springs Creek, a tributary to Johnson Creek, were explained by streamflow and groundwater levels collected for this study, and results from previous studies. High flows of Crystal Springs Creek began in summer 1996, and did not diminish until 2000. Low streamflow of Crystal Springs Creek occurred in 2005. Flow of Crystal Springs Creek related to water-level fluctuations in a nearby well, enabling prediction of streamflow based on groundwater level. Holgate Lake is an ephemeral lake in Southeast Portland that has inundated residential areas several times since the 1940s. The water-surface elevation of the lake closely tracked the elevation of the water table in a nearby well, indicating that the occurrence of the lake is an expression of the water table. Antecedent conditions of the groundwater level and autumn

Sulphur management in onion (Allium cepa) cultivation in hills of Himachal Pradesh.

Science.gov (United States)

Jaggi, R C; Sharma, R K

2010-05-01

Field experiment were conducted at CSK HPKV Research Farm, Palampur during Rabi seasons of 2000-01 and 2001-02, to study the response of onion (Allium cepa var Patna red) at four sulphur levels (0, 15, 30 and 60 kg ha(-1)) applied through Gypsum and S95. The analysis was done to allocate the limited availability of sulphur for maximizing net profit over fertilizer cost. The results show that the dose of sulphur under its full availability is 43.02 kg ha(-1). But under its scarce availability the maximum benefit would occur when it is applied up to 32.11 kg ha(-1) followed by even distribution of fertilizer i.e. 20 kg ha(-1). The returns following sulphur application at these rates, would be Rs 69340, 73092 and 68700 ha(-1) respectively.

Comparison of methods for the determination of reduced inorganic sulphur in acid sulphate soils

International Nuclear Information System (INIS)

Santomartino, S.L.

1999-01-01

Full text: The management of acid sulphate soils requires analytical methods that provide accurate data on the quantity of reduced inorganic sulphur within a soil, as it is this fraction that produces acid upon oxidation. This study uses sulphidic Coode Island Silt samples to compare common analytical methods including POCAS (Peroxide Oxidation-Combined Acidity and Sulphate) which consists of TSA (Total Sulphidic Acidity), S pos (Peroxide Oxidisable Sulphur), TOS (Total Oxidisable Sulphur) and chromium-reducible sulphur. The determination of total sulphur by Leco sulphur is strongly correlated with, but slightly less than, that analysed by XRF. Comparison of soil sulphide content by chromium-reducible sulphur, TSA and TOS methods indicates that TOS values are substantially higher than both other methods. The problem with the TOS method lies in the sulphate extraction procedure. Hot distilled water and HCI are commonly used as extractants, however hot distilled water fails to remove organic sulphur, thereby overestimating the sulphide content of the soil. Leco carbon analyses verify that a substantial proportion of organic matter exists within the samples. The HCI extraction process, which uses Ion Chromatography to analyse for sulphate, produces highly inaccurate results due to the interference of the sulphate peak by the chloride peak during analysis. An alternative method involving HCI extraction and XRF analysis of the soil residue is currently being undertaken. The use of KCI to extract sulphate generally produces values similar to the hot distilled water method. The sulphidic content measured by TSA is strongly correlated with, but slightly higher than that determined by the chromium-reducible sulphur method. This is attributed to the use of hydrogen peroxide in the TSA method, which oxidises organic matter to organic acids in addition to oxidising sulphides. These preliminary findings indicate that the chromium-reducible sulphur method is the most suitable

Integrated sulphur management : gas, oil sands, reclamation and the challenges of fluctuating demand

International Nuclear Information System (INIS)

Pineau, R.

2009-01-01

International Commodities Export Corporation is a privately held company that provides fully integrated service offerings to add maximum value in designing, building, owning, and operating sulphur assets. The company also offers in-house, engineering, procurement and project management, as well as supply management, transportation and distribution services. It also has expertise in marine transportation. This presentation discussed integrated sulphur management, with particular focus on gas, oil sands, reclamation and the challenges of fluctuating demand. The presentation provided an overview of the sulphur market and oil sands sulphur. Key considerations for oil sands producers were also presented. The challenges of fluctuating demand include price and volume considerations; logistics; geography and distance to market; export/offshore versus domestic/United States; seasonal considerations; and an inelastic sulphur market. The presentation concluded with a status update of ICEC's initiative and the advantages of Prince Rupert, an economically viable export infrastructure to producers without onsite forming facilities. figs

The Influence of Slope Breaks on Lava Flow Surface Disruption

Science.gov (United States)

Glaze, Lori S.; Baloga, Stephen M.; Fagents, Sarah A.; Wright, Robert

2014-01-01

Changes in the underlying slope of a lava flow impart a significant fraction of rotational energy beyond the slope break. The eddies, circulation and vortices caused by this rotational energy can disrupt the flow surface, having a significant impact on heat loss and thus the distance the flow can travel. A basic mechanics model is used to compute the rotational energy caused by a slope change. The gain in rotational energy is deposited into an eddy of radius R whose energy is dissipated as it travels downstream. A model of eddy friction with the ambient lava is used to compute the time-rate of energy dissipation. The key parameter of the dissipation rate is shown to be rho R(sup 2/)mu, where ? is the lava density and mu is the viscosity, which can vary by orders of magnitude for different flows. The potential spatial disruption of the lava flow surface is investigated by introducing steady-state models for the main flow beyond the steepening slope break. One model applies to slow-moving flows with both gravity and pressure as the driving forces. The other model applies to fast-moving, low-viscosity, turbulent flows. These models provide the flow velocity that establishes the downstream transport distance of disrupting eddies before they dissipate. The potential influence of slope breaks is discussed in connection with field studies of lava flows from the 1801 Hualalai and 1823 Keaiwa Kilauea, Hawaii, and 2004 Etna eruptions.

Measuring effusion rates of obsidian lava flows by means of satellite thermal data

Science.gov (United States)

Coppola, D.; Laiolo, M.; Franchi, A.; Massimetti, F.; Cigolini, C.; Lara, L. E.

2017-11-01

Space-based thermal data are increasingly used for monitoring effusive eruptions, especially for calculating lava discharge rates and forecasting hazards related to basaltic lava flows. The application of this methodology to silicic, more viscous lava bodies (such as obsidian lava flows) is much less frequent, with only few examples documented in the last decades. The 2011-2012 eruption of Cordón Caulle volcano (Chile) produced a voluminous obsidian lava flow ( 0.6 km3) and offers an exceptional opportunity to analyze the relationship between heat and volumetric flux for such type of viscous lava bodies. Based on a retrospective analysis of MODIS infrared data (MIROVA system), we found that the energy radiated by the active lava flow is robustly correlated with the erupted lava volume, measured independently. We found that after a transient time of about 15 days, the coefficient of proportionality between radiant and volumetric flux becomes almost steady, and stabilizes around a value of 5 × 106 J m- 3. This coefficient (i.e. radiant density) is much lower than those found for basalts ( 1 × 108 J m- 3) and likely reflects the appropriate spreading and cooling properties of the highly-insulated, viscous flows. The effusion rates trend inferred from MODIS data correlates well with the tremor amplitude and with the plume elevation recorded throughout the eruption, thus suggesting a link between the effusive and the coeval explosive activity. Modelling of the eruptive trend indicates that the Cordón Caulle eruption occurred in two stages, either incompletely draining a single magma reservoir or more probably tapping multiple interconnected magmatic compartments.

Shallow and deep controls on lava lake surface motion at Kīlauea Volcano

Science.gov (United States)

Patrick, Matthew R.; Orr, Tim R.; Swanson, Don; Lev, Einat

2016-01-01

Lava lakes provide a rare window into magmatic behavior, and lake surface motion has been used to infer deeper properties of the magmatic system. At Halema'uma'u Crater, at the summit of Kīlauea Volcano, multidisciplinary observations for the past several years indicate that lava lake surface motion can be broadly divided into two regimes: 1) stable and 2) unstable. Stable behavior is driven by lava upwelling from deeper in the lake (presumably directly from the conduit) and is an intrinsic process that drives lava lake surface motion most of the time. This stable behavior can be interrupted by periods of unstable flow (often reversals) driven by spattering – a shallowly-rooted process often extrinsically triggered by small rockfalls from the crater wall. The bursting bubbles at spatter sources create void spaces and a localized surface depression which draws and consumes surrounding surface crust. Spattering is therefore a location of lava downwelling, not upwelling. Stable (i.e. deep, upwelling-driven) and unstable (i.e. shallow, spattering-driven) behavior often alternate through time, have characteristic surface velocities, flow directions and surface temperature regimes, and also correspond to changes in spattering intensity, outgassing rates, lava level and seismic tremor. These results highlight that several processes, originating at different depths, can control the motion of the lava lake surface, and long-term interdisciplinary monitoring is required to separate these influences. These observations indicate that lake surface motion is not always a reliable proxy for deeper lake or magmatic processes. From these observations, we suggest that shallow outgassing (spattering), not lake convection, drives the variations in lake motion reported at Erta 'Ale lava lake.

Sulphur removal from used automotive lubricating oil by ionizing radiation

International Nuclear Information System (INIS)

Scapin, Marcos Antonio; Duarte, Celina Lopes; Sato, Ivone Mulako

2007-01-01

Following the worldwide evolution with the purpose of a higher control of vehicular emissions, the specialists have looked for clean technologies and efficient procedures to make vehicular emissions free of pollutants. Much attention is given to the sulphur concentration in the gasoline, diesel and lubricating oils. The ionizing radiation is a promising technology for the removal of this pollutant when compared to other conventional treatment methods. In this work, the ionizing radiation was used to remove in significant levels the presence of sulphur in automotive motor oil. A 1000 mL sample of used automotive lubricating oil from a gas station was collected. This sample was fractioned and irradiated with 10, 20 50, 100, 200 and 500 kGy doses in a 60 Co irradiator (GAMMACELL-220 - 12 kCi). The 50 and 70% (v/v) of MilliQ water and 30% (v/v) of hydrogen peroxide was used to improve the radiolysis The sulphur element before and after the irradiation was determined by X-ray fluorescence technique (WDXRF) using the Fundamental Parameters Method. The results showed approximately 70% sulphur removal at 500 kGy irradiation dose with 70% (v/v) of MilliQ water addition. (author)

Effect of sulphur fertilisation on yield and quality of white mustard seeds

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Pavel Ryant

2009-01-01

Full Text Available The objective of the present study was to estimate the effect of different forms of sulphur on yields and qualitative parameters of white mustard seeds. This topic was studied in 2004 in the form of a pot trial in a vegetation hall and linked up with an identical experiment with spring wheat conducted in 2003. Besides the control variant not fertilised with sulphur (1 we fertilised the soil with elemental sulphur (2, ammonium sulphate (3 and gypsum (4 and applied foliar dressing of elemental sulphur with bentonite (5. For all variants the nitrogen dose was 0.9 g per pot (0.15 g . kg−1 of soil and for va­riants 2 to 4 it was 1 g of sulphur per pot (0.17 g. kg−1 of soil. Foliar dressing of elemental sulphur (S0 was not applied until the stage of six true leaves in a dose of 10 kg per ha (0.032 g per pot.Significantly higher yields of white mustard seeds were achieved after foliar application of S0 which can be also due to its fungicide action. The variants where gypsum was applied showed the highest average number of branches and pods and also straw yields. After gypsum fertilisation or foliar application of S0 the oil content in the mustard seeds exceeded 25%; this is the minimal content required for the production of good quality mustard. The 1000-seed weight was significantly higher after foliar application of S0. The proportion of seeds greyish on the surface, a sign of mildew, significantly decreased after fertilisation with all forms of sulphur, but most of all after foliar application of S0.Fertilisation with ammonium sulphate reduced the exchangeable soil reaction after harvest. On the other hand gypsum alkalised the soil environment and increased the content of available calcium and water-soluble sulphur. The soil of the variant where foliar dressing of S0 was applied had a higher content of available calcium after harvest. The least amount of available sulphur and phosphorus in the soil was seen after foliar

Investigation of the possibility of binding fly ash particles by elemental sulphur

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Vidojković V.

2006-01-01

Full Text Available Thermal power plants in Serbia use lignite for electrical power production The secondary product of coal combustion is fly ash in the amount of 17%. Fly ash causes the pollution of air, water and soil, and also cause many human, especially lung diseases. Secondary sulphur is a product of crude oil refining. The aim of this study was to investigate the use of sulphur as a bonding material in ultra fine particle agglomeration (smaller than 63 μm in fly ash. The agglomeration should make the ash particles larger and heavy enough to fall without flying fractions. The experiments showed that during the homogenization of the ashes and sulphur from 150 to 170 °C in a reactor with intensive mixing, an amount of 15% sulphur was sufficient to bond particles and cause agglomeration without visible flying fractions.

Tilted lake shorelines record the onset of motion along the Hilton Creek fault adjacent to Long Valley caldera, CA, USA

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Perkins, J. P.; Finnegan, N. J.; Cervelli, P. F.; Langbein, J. O.

2010-12-01

Prominent normal faults occur within and around Long Valley caldera, in the eastern Sierra Nevada of California. However, their relationship to both the magmatic and tectonic evolution of the caldera since the 760 ka eruption of the Bishop Tuff remains poorly understood. In particular, in the Mono-Inyo Craters north of Long Valley, extensional faulting appears to be replaced by dike intrusion where magma is available in the crust. However, it is unclear whether extensional faults in Long Valley caldera have been active since the eruption of the Bishop Tuff (when the current topography was established) or are a relatively young phenomenon owing to the cooling and crystallization of the Long Valley magma reservoir. Here we use GPS geodesy and geomorphology to investigate the evolution of the Hilton Creek fault, the primary range-front fault bounding Long Valley caldera to the southwest. Our primary goals are to determine how long the Hilton Creek fault has been active and whether slip rates have been constant over that time interval. To characterize the modern deformation field, we capitalize on recently (July, 2010) reoccupied GPS benchmarks first established in 1999-2000. These fixed-array GPS data show no discernible evidence for recent slip on the Hilton Creek fault, which further highlights the need for longer-term constraints on fault motion. To establish a fault slip history, we rely on a suite of five prominent shorelines from Pleistocene Long Valley Lake whose ages are well constrained based on field relationships to dated lavas, and that are tilted southward toward the Hilton Creek fault. A preliminary analysis of shoreline orientations using GPS surveys and a 5-m-resolution Topographic Synthetic Aperture Radar (TOPSAR) digital elevation model shows that lake shorelines tilt towards the Hilton Creek fault at roughly parallel gradients (~ 0.6%). The measured shorelines range in inferred age from 100 ka to 500 ka, which constrain recent slip on the Hilton

Transport of metals and sulphur in magmas by flotation of sulphide melt on vapour bubbles

Science.gov (United States)

Mungall, J. E.; Brenan, J. M.; Godel, B.; Barnes, S. J.; Gaillard, F.

2015-03-01

Emissions of sulphur and metals from magmas in Earth’s shallow crust can have global impacts on human society. Sulphur-bearing gases emitted into the atmosphere during volcanic eruptions affect climate, and metals and sulphur can accumulate in the crust above a magma reservoir to form giant copper and gold ore deposits, as well as massive sulphur anomalies. The volumes of sulphur and metals that accumulate in the crust over time exceed the amounts that could have been derived from an isolated magma reservoir. They are instead thought to come from injections of multiple new batches of vapour- and sulphide-saturated magmas into the existing reservoirs. However, the mechanism for the selective upward transfer of sulphur and metals is poorly understood because their main carrier phase, sulphide melt, is dense and is assumed to settle to the bottoms of magma reservoirs. Here we use laboratory experiments as well as gas-speciation and mass-balance models to show that droplets of sulphide melt can attach to vapour bubbles to form compound drops that float. We demonstrate the feasibility of this mechanism for the upward mobility of sulphide liquids to the shallow crust. Our work provides a mechanism for the atmospheric release of large amounts of sulphur, and contradicts the widely held assumption that dense sulphide liquids rich in sulphur, copper and gold will remain sequestered in the deep crust.

Experimental Insights on Natural Lava-Ice/Snow Interactions and Their Implications for Glaciovolcanic and Submarine Eruptions

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Edwards, B. R.; Karson, J.; Wysocki, R.; Lev, E.; Bindeman, I. N.; Kueppers, U.

2012-12-01

Lava-ice-snow interactions have recently gained global attention through the eruptions of ice-covered volcanoes, particularly from Eyjafjallajokull in south-central Iceland, with dramatic effects on local communities and global air travel. However, as with most submarine eruptions, direct observations of lava-ice/snow interactions are rare. Only a few hundred potentially active volcanoes are presently ice-covered, these volcanoes are generally in remote places, and their associated hazards make close observation and measurements dangerous. Here we report the results of the first large-scale experiments designed to provide new constraints on natural interactions between lava and ice/snow. The experiments comprised controlled effusion of tens of kilograms of melted basalt on top of ice/snow, and provide insights about observations from natural lava-ice-snow interactions including new constraints for: 1) rapid lava advance along the ice-lava interface; 2) rapid downwards melting of lava flows through ice; 3) lava flow exploitation of pre-existing discontinuities to travel laterally beneath and within ice; and 4) formation of abundant limu o Pele and non-explosive vapor transport from the base to the top of the lava flow with minor O isotope exchange. The experiments are consistent with observations from eruptions showing that lava is more efficient at melting ice when emplaced on top of the ice as opposed to beneath the ice, as well as the efficacy of tephra cover for slowing melting. The experimental extrusion rates are as within the range of those for submarine eruptions as well, and reproduce some features seen in submarine eruptions including voluminous production of gas rich cavities within initially anhydrous lavas and limu on lava surfaces. Our initial results raise questions about the possibility of secondary ingestion of water by submarine and glaciovolcanic lava flows, and the origins of apparent primary gas cavities in those flows. Basaltic melt moving down

Operational tracking of lava lake surface motion at Kīlauea Volcano, Hawai‘i

Science.gov (United States)

Patrick, Matthew R.; Orr, Tim R.

2018-03-08

Surface motion is an important component of lava lake behavior, but previous studies of lake motion have been focused on short time intervals. In this study, we implement the first continuous, real-time operational routine for tracking lava lake surface motion, applying the technique to the persistent lava lake in Halema‘uma‘u Crater at the summit of Kīlauea Volcano, Hawai‘i. We measure lake motion by using images from a fixed thermal camera positioned on the crater rim, transmitting images to the Hawaiian Volcano Observatory (HVO) in real time. We use an existing optical flow toolbox in Matlab to calculate motion vectors, and we track the position of lava upwelling in the lake, as well as the intensity of spattering on the lake surface. Over the past 2 years, real-time tracking of lava lake surface motion at Halema‘uma‘u has been an important part of monitoring the lake’s activity, serving as another valuable tool in the volcano monitoring suite at HVO.

The isotopic composition of postshield lavas from Mauna Kea volcano, Hawaii

International Nuclear Information System (INIS)

Kennedy, A.K.; Fray, F.A.; Kwon, S.T.; West, H.B.

1991-01-01

The postshield eruptive stage of Mauna Kea volcano, Hawaii, can be divided into an early basaltic substage, the Hamakua Volcanics, containing picrites, ankaramites, alkalic and tholeiitic basalt, and a hawaiite substage, the Laupahoehoe Volcanics, containing only hawaiites and rare mugearites. Cumulate gabbroic xenoliths in Laupahoehoe Volcanics have isotopic ratios similar to the Hamakua Volcanics, and these gabbros provide constaints on the crustal evolution of Mauna Kea lavas. Because of the small variation in 87 Sr/ 86 Sr (0.70335-0.70362), 143 Nd/ 144 Nd (0.51297-0.51308) and 206 Pb/ 204 Pb (18.306-18.440), lavas from both substages must contain relatively fixed proportions of depleted, enriched and primitive mantle components. In addition, there is Sr, Nd and Pb isotopic overlap between tholeiitic and alkalic Hamakua basalts. However, the steep 207 Pb/ 204 Pb vs. 206 Pb/ 204 Pb arrays of postshield lavas from Mauna Kea, West Maui and Haleakala volcanoes and the existence of rare samples with high 207 Pb/ 204 Pb, up to 15.548, requires an unusual component in some Hawaiian lavas. This component is unlikely to be derived from sediments or MORB lithosphere, and it may be a minor plume component. Lavas erupted during the postshield stage of Mauna Kea volcano do not define a systematic temporal trend of varying 87 Sr/ 86 Sr and 143 Nd/ 144 Nd. This result contrasts with the temporal trend defined by lavas from Haleakala Volcano and provides evidence for important differences between the origin and evolution of different Hawaiian volcanoes. However, the Laupahoehoe Volcanics trend to lower 206 Pb/ 204 Pb ratios than the Hamakua Volcanics. (orig./WL)

Surface-water and ground-water quality in the Powell Creek and Armstrong Creek Watersheds, Dauphin County, Pennsylvania, July-September 2001

Science.gov (United States)

Galeone, Daniel G.; Low, Dennis J.

2003-01-01

Powell Creek and Armstrong Creek Watersheds are in Dauphin County, north of Harrisburg, Pa. The completion of the Dauphin Bypass Transportation Project in 2001 helped to alleviate traffic congestion from these watersheds to Harrisburg. However, increased development in Powell Creek and Armstrong Creek Watersheds is expected. The purpose of this study was to establish a baseline for future projects in the watersheds so that the effects of land-use changes on water quality can be documented. The Pennsylvania Department of Environmental Protection (PADEP) (2002) indicates that surface water generally is good in the 71 perennial stream miles in the watersheds. PADEP lists 11.1 stream miles within the Armstrong Creek and 3.2 stream miles within the Powell Creek Watersheds as impaired or not meeting water-quality standards. Siltation from agricultural sources and removal of vegetation along stream channels are cited by PADEP as likely factors causing this impairment.

Concentric cylinder viscometry at subliquidus conditions on Mauna Ulu lavas, Kilauea Volcano, Hawaii

Science.gov (United States)

Sehlke, A.; Robert, B.; Harris, A. J.; gurioli, L.; Whittington, A. G.

2013-12-01

The morphology of lava flows is controlled by the physical properties of the lava and its effusion rates, as well as environmental influences such as surface medium, slope and ambient temperature and pressure conditions. The important physical properties of lavas include viscosity (η), yield strength (σy), thermal diffusivity (κ) and heat capacity (CP), all of which strongly depend on temperature (T), composition (Χ), crystal fraction (φc) and vesicularity (φb). The crystal fraction (φc) typically increase as temperature decreases, and therefore is temperature dependent itself and influences the residual liquid composition (Χ). The rheological behavior of multi-phase lavas in lava flows is expressed as different flow types, forced from a smooth pahoehoe to a blocky ';a'a within a transition zone. Recent field studies of overflow units at the Muliwai a Pele lava flow erupted from Mauna Ulu in 1974 on Kilauea volcano (Hawaii) reveal a transition zone in a distance approximately 4.5 km from the vent as a result of a cooling gradient of 6 °C/km, crystallization rates of 0.05/km and a density increase from 1010 × 150 kg/m3 near to 1410 × 120 kg/m3 6 km distant from the vent due to degassing. Concentric cylinder viscometry under atmospheric conditions has been conducted in order to investigate the rheological response of crystal-liquid lava suspensions at different equilibrium temperatures for Mauna Ulu lavas. We detect first solid phases around 1230 °C being clinopyroxene, olivine and spinel, followed by plagioclase appearing as microlites as observed in natural rock samples. Measured apparent viscosities (ηapp) with applied strain rates between 50 s-1 and 0.3 s-1 at 1201 °C, 1192 °C and 1181 °C show a strong stress-strain rate dependency, classifying our 2-phase suspensions as Herschel-Bulkey fluids with an extrapolated apparent yield strength (τ0) around 200 to 150 Pa in presence of different crystal fractions, resulting in a 2.5 fold increase of

Simulation of Water Quality in the Tull Creek and West Neck Creek Watersheds, Currituck Sound Basin, North Carolina and Virginia

Science.gov (United States)

Garcia, Ana Maria

2009-01-01

A study of the Currituck Sound was initiated in 2005 to evaluate the water chemistry of the Sound and assess the effectiveness of management strategies. As part of this study, the Soil and Water Assessment Tool (SWAT) model was used to simulate current sediment and nutrient loadings for two distinct watersheds in the Currituck Sound basin and to determine the consequences of different water-quality management scenarios. The watersheds studied were (1) Tull Creek watershed, which has extensive row-crop cultivation and artificial drainage, and (2) West Neck Creek watershed, which drains urban areas in and around Virginia Beach, Virginia. The model simulated monthly streamflows with Nash-Sutcliffe model efficiency coefficients of 0.83 and 0.76 for Tull Creek and West Neck Creek, respectively. The daily sediment concentration coefficient of determination was 0.19 for Tull Creek and 0.36 for West Neck Creek. The coefficient of determination for total nitrogen was 0.26 for both watersheds and for dissolved phosphorus was 0.4 for Tull Creek and 0.03 for West Neck Creek. The model was used to estimate current (2006-2007) sediment and nutrient yields for the two watersheds. Total suspended-solids yield was 56 percent lower in the urban watershed than in the agricultural watershed. Total nitrogen export was 45 percent lower, and total phosphorus was 43 percent lower in the urban watershed than in the agricultural watershed. A management scenario with filter strips bordering the main channels was simulated for Tull Creek. The Soil and Water Assessment Tool model estimated a total suspended-solids yield reduction of 54 percent and total nitrogen and total phosphorus reductions of 21 percent and 29 percent, respectively, for the Tull Creek watershed.

Thermophysical properties of the Lipari lavas (Southern Tyrrhenian Sea

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D. Russo

1997-06-01

Full Text Available Results of thermophysical investigations into the lavas of the island of Lipari (Southern Tyrrhenian Sea are presented. Samples selected for laboratory measurements belong to four main magmatic cycles, which produced basaltic-andesitic, andesitic and rhyolitic lavas. The wet-bulk density and the thermal conductivity measured on 69 specimens range from 1900 to 2760 kg m-3 and from 1.02 to 2.88 W m-1 K-1, respectively. Porosity is never negligible and its influence on density is maximum in rhyolites of the third cycle. The thermal conductivity is also influenced by the amount of glass. Rhyolitic obsidians show values lower than other rhyolites, although the latter rocks have a larger average porosity. The radioactive heat production determined on 36 specimens varies with the rock type, depending on the amount of U, Th and K. In basic lavas of the first cycle its value is 0.95°± 0.30 mW m-3, while in rhyolites of the fourth cycle it attains 6.68°±0.61 mW m-3. A comparison between results of g-ray spectrometry and X-ray fluorescence points out that the assumption of equilibrium in the decay series of the isotopic elements seems fulfilled. The information obtained is useful not only for the interpretation of geophysical surveys but also for the understanding of the geochemical characteristics of lavas.

Effect of feedstock end boiling point on product sulphur during ultra deep diesel hydrodesulphurization

Energy Technology Data Exchange (ETDEWEB)

Stratiev, D.; Ivanov, A.; Jelyaskova, M. [Lukoil Neftochim Bourgas AD, Bourgas (Bulgaria)

2004-12-01

An investigation was carried out to test the feasibility of producing 50 and 10 ppm sulphur diesel in a conventional hydrotreating unit operating at low pressure conditions by varying the feedstock end boiling point. Middle distillate fractions distilled from a mixture of Ural crude oil, reduced crude, vacuum gas oil, naphtha and low sulphur crude oils with 95% vol. points of 274, 359, 343, 333, and 322 C (ASTM D-86 method) and sulphur contents of 0.36, 0.63, 0.99, 0.57, and 0.47%, respectively, were hydrotreated using the Akzo Nobel Stars family Co-Mo KF-757 catalyst in a trickle bed pilot plant at following conditions: reactor inlet temperature range of 320-360 C; liquid hourly space velocity (LHSV) range of 1-2 h{sup -1}; total reactor pressure of 3.5 MPa; treating gas: feedstock ratio of 250 Nm{sup 3}/m{sup 3}. It was found that the determinant factor for the attainment of ultra low sulphur levels during middle distillate hydrodesulphurization was not the total sulphur content in the feed but the content of the material boiling above 340 C (according to TBP). For all LHSVs and reactor inlet temperatures studied the product sulphur dependence on the feed 340 C+ fraction content was approximated by second order power law. The specification of 50 ppm sulphur was achieved with all studied feedstocks. However the 10ppm sulphur limit could be met only by feedstocks with 95% vol. points below 333 C, which is accompanied by about 10% reduction of the diesel potential. The hydrotreatment tests on a blend 80% straight run gas oil (ASTM D-86 95% vol. of 274 C)/20%FCC LCO (ASTM D-86 95% vol. of 284 C) showed product sulphur levels which were not higher than those obtained by hydrotreatment of the straight run gas oil, indicating that undercutting the FCC LCO gives the refiner the opportunity to increase the potential for the production of 10 ppm sulphur diesel at the conditions of the conventional hydrotreating unit operating at low pressure. The product cetane index was

Subaqueous rhyolite block lavas in the Miocene Ushikiri Formation, Shimane Peninsula, SW Japan

Science.gov (United States)

Kano, Kazuhiko; Takeuchi, Keiji; Yamamoto, Takahiro; Hoshizumi, Hideo

1991-06-01

A rhyolite mass of the Miocene Ushikiri Formation in the western part of the Shimane Peninsula, SW Japan, is a small subaqueous edifice about 600 m high and 4 km wide, formed at water depths between 200 and 1000 m. It consists mainly of three relatively flat, lava-flow units 50-300 m in maximum thickness, each of which includes lobes and their polyhedral fragments. The lava lobes are poorly to well vesiculated, glassy to microcrystalline and flow-banded and -folded. Compared with mafic pillows, they are large, having thick, quenched and brecciated, glassy crusts because of their high viscosity, surface tension and thermal conductivity. Their surfaces disintegrate into polyhedral fragments and grade into massive volcanic breccia. The massive volcanic breccia composed of the lobe fragments is poorly sorted and covered with stratified volcanic breccia of the same rock type. The rhyolite lavas commonly bifurcate in a manner similar to mafic pillow lavas. However, they are highly silicic with 1-5 vol.% phenocrysts and have elongated vesicles and flow-folds, implying that they were visco-plastic during flowage. Their surface features are similar to those of subaerial block lava. With respect to rheological and morphological features, they are subaqueous equivalents of block lava.

Degassing driving crystallization of plagioclase phenocrysts in lava tube stalactites on Mount Etna (Sicily, Italy)

Science.gov (United States)

Lanzafame, Gabriele; Ferlito, Carmelo

2014-10-01

Basaltic lava flows can form tubes in response to the cooling of the outer surface. We collected lava stalactites (frozen lava tears) and sampled lava from the ceilings of three lava tubes on Mount Etna. Comparison of the petrographic characters between ceiling lavas and relative stalactites reveals surprising differences in the groundmass textures and crystal compositions. Major and trace element contents in stalactites show only a slight increase in alkali and SiO2 compared to ceiling lava, whereas significant differences exist in composition and textures between plagioclases within the ceiling lava and those within the stalactites, being in the last case definitively more An-rich. We advance the hypothesis that the high temperature reached in the cave caused the exsolution of the volatiles still trapped in the dripping melt. The volatiles, mainly H2O, formed bubbles and escaped from the melt; such a water-loss might have promoted the silicate polymerization in the stalactites resulting in the growth of An-rich plagioclase phenocrysts. Our results have important implications: in fact plagioclase phenocrysts are usually associated with intratelluric growth and are often considered as the main petrologic evidence for the existence of a magma chamber. The textural and chemical features of plagioclases in stalactites prove that phenocryst growth in syn to post-eruptive conditions is plausible and clearly explains the relatively low viscosity of many phenocryst-rich lava flows on Mount Etna, as well as on many other volcanoes around the world. Therefore, we can conclude that plagioclase phenocrysts cannot exclusively be considered as having originated within a magma chamber.

Continuous gravity measurements reveal a low-density lava lake at Kīlauea Volcano, Hawai‘i

Science.gov (United States)

Carbone, Daniele; Poland, Michael P.; Patrick, Matthew R.; Orr, Tim R.

2013-01-01

On 5 March 2011, the lava lake within the summit eruptive vent at Kīlauea Volcano, Hawai‘i, began to drain as magma withdrew to feed a dike intrusion and fissure eruption on the volcanoʼs east rift zone. The draining was monitored by a variety of continuous geological and geophysical measurements, including deformation, thermal and visual imagery, and gravity. Over the first ∼14 hours of the draining, the ground near the eruptive vent subsided by about 0.15 m, gravity dropped by more than 100 μGal, and the lava lake retreated by over 120 m. We used GPS data to correct the gravity signal for the effects of subsurface mass loss and vertical deformation in order to isolate the change in gravity due to draining of the lava lake alone. Using a model of the eruptive vent geometry based on visual observations and the lava level over time determined from thermal camera data, we calculated the best-fit lava density to the observed gravity decrease — to our knowledge, the first geophysical determination of the density of a lava lake anywhere in the world. Our result, 950 +/- 300 kg m-3, suggests a lava density less than that of water and indicates that Kīlaueaʼs lava lake is gas-rich, which can explain why rockfalls that impact the lake trigger small explosions. Knowledge of such a fundamental material property as density is also critical to investigations of lava-lake convection and degassing and can inform calculations of pressure change in the subsurface magma plumbing system.

Distribution of sulphur and trace elements in peat. A literature survey with some additional sulphur analyses

Energy Technology Data Exchange (ETDEWEB)

Huttunen, S; Karhu, M

1981-01-01

A survey on the literature and contemporary research was made on peat sulphur and trace element studies. Marked variance between different peatlands and peat types has been noted. The available information is still inadequate for generalizations or statistical analysis mainly due to methodological variations and temporal and spatial variations in results. At the moment, the criteria applied in peatland inventories and evaluations are inadequate with respect to peat quality determinations. To some extent the quality of fuel peat should be determined in a mire inventory prior to peatland utilization. The areas over sulphide clay and some sulphate depositions may considerably increase the peat sulphur content. A proposal has been made to include the sulphur content monitoring in the cases where it exceeds 0.3 per cent. The trace elements may also bring about an increase in peat emissions if the deepest peat layers or polluted layers are burnt. The most important elements in this respect are Al, Fe, Mn, Pb, Zn, V, Ni, Hg, Cu, Cr, as well as As and U. The first ten because of the relatively high concentrations and last two because of pollution or toxocity and ore deposit factors. The peat hydrogen ion concentration has a positive correlation with copper and vanadium. The correlation is positive with the cobalt and nickel contents when the pH is low, and negative at a higher pH. A general peat type correlation shows maximum trace element contents in basal Carex peats with subsoil effects. The peat ash content and the Ti, Pb, V, Cr, Ni, and S contents have positive correlations. (Refs. 290).

Dispersion of sulphur in the northern hemisphere. A study with a 3-dimensional time-resolved model

Energy Technology Data Exchange (ETDEWEB)

Tarrason, L

1996-12-31

This thesis on atmospheric dispersion of sulphur presents a calculation of intercontinental transport of oxidized sulphur and allocates different contributions to sulphur background levels over Europe. It is found that a significant fraction of anthropogenic sulphur (AS) is transported out of continental boundaries thus affecting the background levels over major parts of the northern hemisphere. Over Europe, the contribution of AS from North America is similar in amount to that of Asian AS and natural sources from the North Atlantic Ocean. Although the yearly contribution of intercontinental transport to deposition of sulphur over Europe is quite small, it can be much more important over certain areas and seasons and is comparable to the contributions from individual European countries. The calculations are based on a three-dimensional Eulerian time-resolved model that describes sulphur dispersion in the atmosphere in connection with large-scale synoptic flows and agree well with observations. The thesis emphasizes the role of synoptic scale atmospheric motions in determining intercontinental transport of sulphur. It indicates the need to resolve individual cyclones and anticyclones in order to describe the dispersion and distribution of atmospheric sulphur in the northern hemisphere and stresses the value of comparing model calculations with observations, both in atmospheric chemistry studies and in climate applications. 260 refs., 50 figs., 17 tabs.

Dispersion of sulphur in the northern hemisphere. A study with a 3-dimensional time-resolved model

Energy Technology Data Exchange (ETDEWEB)

Tarrason, L.

1995-12-31

This thesis on atmospheric dispersion of sulphur presents a calculation of intercontinental transport of oxidized sulphur and allocates different contributions to sulphur background levels over Europe. It is found that a significant fraction of anthropogenic sulphur (AS) is transported out of continental boundaries thus affecting the background levels over major parts of the northern hemisphere. Over Europe, the contribution of AS from North America is similar in amount to that of Asian AS and natural sources from the North Atlantic Ocean. Although the yearly contribution of intercontinental transport to deposition of sulphur over Europe is quite small, it can be much more important over certain areas and seasons and is comparable to the contributions from individual European countries. The calculations are based on a three-dimensional Eulerian time-resolved model that describes sulphur dispersion in the atmosphere in connection with large-scale synoptic flows and agree well with observations. The thesis emphasizes the role of synoptic scale atmospheric motions in determining intercontinental transport of sulphur. It indicates the need to resolve individual cyclones and anticyclones in order to describe the dispersion and distribution of atmospheric sulphur in the northern hemisphere and stresses the value of comparing model calculations with observations, both in atmospheric chemistry studies and in climate applications. 260 refs., 50 figs., 17 tabs.

Effect of Sulphur Fertilization on Grain Quality and Protein Composition of Durum Wheat (Triticum durum Desf.

Directory of Open Access Journals (Sweden)

Marianna Pompa

2009-12-01

Full Text Available The reduction of atmosphere emission of SO2 and the massive use of fertilizers high in nitrogen and phosphorus resulted in a decrease of the sulphur content in the soil. In durum wheat cultivation, sulphur supply plays a key role not only for plant growth, but also for grain quality. Sulphur is an essential macronutrient primarily used to synthesize methionine and cysteine and it is also involved in establishing protein structures by disulphide bonds. The aim of this study was to evaluate the effect of sulphur nutrition on grain quality and protein composition of durum wheat cultivars grown under water deficit conditions, typical of Mediterranean areas. To this purpose, in the 2003-2004 and 2004-2005 crop seasons a field trial was carried out by comparing two water regimes (irrigated and rainfed, two sulphur fertilizer levels and two durum wheat cultivars. Under our experimental conditions, an increase in protein and gluten content in the rainfed treatment and a positive effect of sulphur fertilization on quality parameters were observed. Few changes were observed in protein composition in response to sulphur fertilization.

Simulation of core melt spreading with lava: theoretical background and status of validation

International Nuclear Information System (INIS)

Allelein, H.-J.; Breest, A.; Spengler, C.

2000-01-01

The goal of this paper is to present the GRS R and D achievements and perspectives of its approach to simulate ex-vessel core melt spreading. The basic idea followed by GRS is the analogy of core melt spreading to volcanic lava flows. A fact first proposed by Robson (1967) and now widely accepted is that lava rheologically behaves as a Bingham fluid, which is characterized by yield stress and plastic viscosity. Recent experimental investigations by Epstein (1996) reveal that corium-concrete mixtures may be described as Bingham fluids. The GRS code LAVA is based on a successful lava flow model, but is adapted to prototypic corium and corium-simulation spreading. Furthermore some detailed physical models such as a thermal crust model on the free melt surface and a model for heat conduction into the substratum are added. Heat losses of the bulk, which is represented by one mean temperature, are now determined by radiation and by temperature profiles in the upper crust and in the substratum. In order to reduce the weak mesh dependence of the original algorithm, a random space method of cellular automata is integrated, which removes the mesh bias without increasing calculation time. LAVA is successfully validated against a lot of experiments using different materials spread. The validation process has shown that LAVA is a robust and fast running code to simulate corium-type spreading. LAVA provides all integral information of practical interest (spreading length, height of the melt after stabilization) and seems to be an appropriate tool for handling large core melt masses within a plant application. (orig.)

Comparison of the SAWNUC model with CLOUD measurements of sulphuric acid-water nucleation.

Science.gov (United States)

Ehrhart, Sebastian; Ickes, Luisa; Almeida, Joao; Amorim, Antonio; Barmet, Peter; Bianchi, Federico; Dommen, Josef; Dunne, Eimear M; Duplissy, Jonathan; Franchin, Alessandro; Kangasluoma, Juha; Kirkby, Jasper; Kürten, Andreas; Kupc, Agnieszka; Lehtipalo, Katrianne; Nieminen, Tuomo; Riccobono, Francesco; Rondo, Linda; Schobesberger, Siegfried; Steiner, Gerhard; Tomé, António; Wimmer, Daniela; Baltensperger, Urs; Wagner, Paul E; Curtius, Joachim

2016-10-27

Binary nucleation of sulphuric acid-water particles is expected to be an important process in the free troposphere at low temperatures. SAWNUC (Sulphuric Acid Water Nucleation) is a model of binary nucleation that is based on laboratory measurements of the binding energies of sulphuric acid and water in charged and neutral clusters. Predictions of SAWNUC are compared for the first time comprehensively with experimental binary nucleation data from the CLOUD chamber at European Organization for Nuclear Research. The experimental measurements span a temperature range of 208-292 K, sulphuric acid concentrations from 1·10 6 to 1·10 9  cm -3 , and distinguish between ion-induced and neutral nucleation. Good agreement, within a factor of 5, is found between the experimental and modeled formation rates for ion-induced nucleation at 278 K and below and for neutral nucleation at 208 and 223 K. Differences at warm temperatures are attributed to ammonia contamination which was indicated by the presence of ammonia-sulphuric acid clusters, detected by an Atmospheric Pressure Interface Time of Flight (APi-TOF) mass spectrometer. APi-TOF measurements of the sulphuric acid ion cluster distributions ( (H2SO4)i·HSO4- with i = 0, 1, ..., 10) show qualitative agreement with the SAWNUC ion cluster distributions. Remaining differences between the measured and modeled distributions are most likely due to fragmentation in the APi-TOF. The CLOUD results are in good agreement with previously measured cluster binding energies and show the SAWNUC model to be a good representation of ion-induced and neutral binary nucleation of sulphuric acid-water clusters in the middle and upper troposphere.

Sulphur Mustard Poisoning and Its Complications in Iranian Veterans

Directory of Open Access Journals (Sweden)

Beeta Balali-Mood

2009-09-01

Full Text Available Sulphur mustard is a chemical warfare agent, which was largelyused during the World War One and in Iraq-Iran conflict. It mayalso be used as a chemical terrorism agent. Therefore, medicalprofessions should have sufficient knowledge and be preparedfor medical intervention of any such chemical attack.Sulphur mustard exerts direct toxic effects on the eyes, skin,and respiratory tract, with subsequent systemic actions on thenervous, immunologic, hematologic, digestive, and reproductivesystems. It is an alkylating agent that affects DNA synthesis andthus, delayed complications have been considered since theWorld War One. Cases of malignancies in the target organs particularlyin hematopoietic, respiratory, and digestive systemswere reported. Common delayed respiratory complications includechronic bronchitis, bronchiectasis, frequent bronchopneumonia,and pulmonary fibrosis, all of which tend to deterioratewith time. Severe dry skin, delayed keratitis, and reduction ofnatural killer cells with subsequent increased risk of infectionsand malignancies are also among the most distressing long-termconsequences of sulphur mustard intoxication. However, despiteextensive research that has been conducted on Iranian veteransduring the past decades, major gaps continue to remain in thesulphur mustard literature. Immunological and neurological dysfunctionsand the relationship between exposure to sulphur mustardand mutagenicity, carcinogenicity, and teratogenicity areimportant fields that require further studies, particularly on Iranianveterans with chronic health problems caused by sulphurmustard poisoning. There is also a paucity of information on themedical management of acute and delayed toxic effects of sulphurmustard poisoning, a subject that greatly challenges themedical professions.

Relative ages of lava flows at Alba Patera, Mars

International Nuclear Information System (INIS)

Schneeberger, D.M.; Pieri, D.C.

1987-01-01

Many large lava flows on the flanks of Alba Patera are astonishing in their volume and length. As a suite, these flows suggest tremendously voluminous and sustained eruptions, and provide dimensional boundary conditions typically a factor of 100 larger than terrestrial flows. One of the most striking features associated with Alba Patera is the large, radially oriented lava flows that exhibit a variety of flow morphologies. These include sheet flows, tube fed and tube channel flows, and undifferentiated flows. Three groups of flows were studied; flows on the northwest flank, southeast flank, and the intracaldera region. The lava flows discussed probably were erupted as a group during the same major volcanic episode as suggested by the data presented. Absolute ages are poorly constrained for both the individual flows and shield, due in part to disagreement as to which absolute age curve is representative for Mars. A relative age sequence is implied but lacks precision due to the closeness of the size frequency curves

Geochemical discrimination of five pleistocene Lava-Dam outburst-flood deposits, western Grand Canyon, Arizona

Science.gov (United States)

Fenton, C.R.; Poreda, R.J.; Nash, B.P.; Webb, R.H.; Cerling, T.E.

2004-01-01

Pleistocene basaltic lava dams and outburst-flood deposits in the western Grand Canyon, Arizona, have been correlated by means of cosmogenic 3He (3Hec) ages and concentrations of SiO2, Na2O, K2O, and rare earth elements. These data indicate that basalt clasts and vitroclasts in a given outburst-flood deposit came from a common source, a lava dam. With these data, it is possible to distinguish individual dam-flood events and improve our understanding of the interrelations of volcanism and river processes. At least five lava dams on the Colorado River failed catastrophically between 100 and 525 ka; subsequent outburst floods emplaced basalt-rich deposits preserved on benches as high as 200 m above the current river and up to 53 km downstream of dam sites. Chemical data also distinguishes individual lava flows that were collectively mapped in the past as large long-lasting dam complexes. These chemical data, in combination with age constraints, increase our ability to correlate lava dams and outburst-flood deposits and increase our understanding of the longevity of lava dams. Bases of correlated lava dams and flood deposits approximate the elevation of the ancestral river during each flood event. Water surface profiles are reconstructed and can be used in future hydraulic models to estimate the magnitude of these large-scale floods.

33 CFR 207.170d - Taylor Creek, navigation lock (S-193) across the entrance to Taylor Creek at Lake Okeechobee...

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Taylor Creek, navigation lock (S-193) across the entrance to Taylor Creek at Lake Okeechobee, Okeechobee, Fla.; use, administration..., DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE NAVIGATION REGULATIONS § 207.170d Taylor Creek, navigation lock...

Kīlauea summit eruption—Lava returns to Halemaʻumaʻu

Science.gov (United States)

Babb, Janet L.; Wessells, Stephen M.; Neal, Christina A.

2017-10-06

In March 2008, a new volcanic vent opened within Halemaʻumaʻu, a crater at the summit of Kīlauea Volcano in Hawaiʻi Volcanoes National Park on the Island of Hawaiʻi. This new vent is one of two ongoing eruptions on the volcano. The other is on Kīlauea’s East Rift Zone, where vents have been erupting nearly nonstop since 1983. The duration of these simultaneous summit and rift zone eruptions on Kīlauea is unmatched in at least 200 years.Since 2008, Kīlauea’s summit eruption has consisted of continuous degassing, occasional explosive events, and an active, circulating lava lake. Because of ongoing volcanic hazards associated with the summit vent, including the emission of high levels of sulfur dioxide gas and fragments of hot lava and rock explosively hurled onto the crater rim, the area around Halemaʻumaʻu remains closed to the public as of 2017.Through historical photos of past Halemaʻumaʻu eruptions and stunning 4K imagery of the current eruption, this 24-minute program tells the story of Kīlauea Volcano’s summit lava lake—now one of the two largest lava lakes in the world. It begins with a Hawaiian chant that expresses traditional observations of a bubbling lava lake and reflects the connections between science and culture that continue on Kīlauea today.The video briefly recounts the eruptive history of Halemaʻumaʻu and describes the formation and continued growth of the current summit vent and lava lake. It features USGS Hawaiian Volcano Observatory scientists sharing their insights on the summit eruption—how they monitor the lava lake, how and why the lake level rises and falls, why explosive events occur, the connection between Kīlauea’s ongoing summit and East Rift Zone eruptions, and the impacts of the summit eruption on the Island of Hawaiʻi and beyond. The video is also available at the following U.S. Geological Survey Multimedia Gallery link (video hosted on YouTube): Kīlauea summit eruption—Lava returns to Halemaʻumaʻu

Growth and yield response of sunflower (helianthus annuus l.) to sulphur and boron application

International Nuclear Information System (INIS)

Tahir, M.; Shah, S.A.; Tanveer, A.; Rehman, H.U.

2014-01-01

An experiment was conducted to study the growth and yield response of sunflower to sulphur and boron application. Sulphur (control, 15, 30 kg/ha) and foliar sprays of 1% boron solution (control, spray at 4 week after emergence, 20 days after first spray, at 4 weeks after germination + 20 days after first spray) was applied in soil. The results showed significant increase of all growth and yield parameters by varying levels of sulphur and boron application. Application of 30 kg sulphur/ha enhanced stem diameter (1.99 cm), number of achene per head (765.75) and oil content (36.42%). In case of combined use of sulphur and boron application, maximum plant height (171 cm), head diameter (20.71 cm), 1000-achene weight (54.56 g), biological yield (16.49 t/ha) and achene yield (3.99 t/ha) was recorded by the application of 2 sprays of boron solution (1%) at 4 weeks after germination and reproductive stage. (author)

Summer food habits and trophic overlap of roundtail chub and creek chub in Muddy Creek, Wyoming

Science.gov (United States)

Quist, M.C.; Bower, M.R.; Hubert, W.A.

2006-01-01

Native fishes of the Upper Colorado River Basin have experienced substantial declines in abundance and distribution, and are extirpated from most of Wyoming. Muddy Creek, in south-central Wyoming (Little Snake River watershed), contains sympatric populations of native roundtail chub (Gila robusta), bluehead sucker, (Catostomus discobolus), and flannelmouth sucker (C. tatipinnis), and represents an area of high conservation concern because it is the only area known to have sympatric populations of all 3 species in Wyoming. However, introduced creek chub (Semotilus atromaculatus) are abundant and might have a negative influence on native fishes. We assessed summer food habits of roundtail chub and creek chub to provide information on the ecology of each species and obtain insight on potential trophic overlap. Roundtail chub and creek chub seemed to be opportunistic generalists that consumed a diverse array of food items. Stomach contents of both species were dominated by plant material, aquatic and terrestrial insects, and Fishes, but also included gastropods and mussels. Stomach contents were similar between species, indicating high trophic, overlap. No length-related patterns in diet were observed for either species. These results suggest that creek chubs have the potential to adversely influence the roundtail chub population through competition for food and the native fish assemblage through predation.

LAVA: a conceptual framework for automated risk assessment

International Nuclear Information System (INIS)

Smith, S.T.; Brown, D.C.; Erkkila, T.H.; FitzGerald, P.D.; Lim, J.J.; Massagli, L.; Phillips, J.R.; Tisinger, R.M.

1986-01-01

At the Los Alamos National Laboratory we are developing the framework for generating knowledge-based systems that perform automated risk analyses on an organization's assets. An organization's assets can be subdivided into tangible and intangible assets. Tangible assets include facilities, materiel, personnel, and time, while intangible assets include such factors as reputation, employee morale, and technical knowledge. The potential loss exposure of an asset is dependent upon the threats (both static and dynamic), the vulnerabilities in the mechanisms protecting the assets from the threats, and the consequences of the threats successfully exploiting the protective systems vulnerabilities. The methodology is based upon decision analysis, fuzzy set theory, natural-language processing, and event-tree structures. The Los Alamos Vulnerability and Risk Assessment (LAVA) methodology has been applied to computer security. LAVA is modeled using an interactive questionnaire in natural language and is fully automated on a personal computer. The program generates both summary reports for use by both management personnel and detailed reports for use by operations staff. LAVA has been in use by the Nuclear Regulatory Commission and the National Bureau of Standards for nearly two years and is presently under evaluation by other governmental agencies. 7 refs

LAVA: An Open-Source Approach To Designing LAMP (Loop-Mediated Isothermal Amplification DNA Signatures

Directory of Open Access Journals (Sweden)

Gardner Shea N

2011-06-01

Full Text Available Abstract Background We developed an extendable open-source Loop-mediated isothermal AMPlification (LAMP signature design program called LAVA (LAMP Assay Versatile Analysis. LAVA was created in response to limitations of existing LAMP signature programs. Results LAVA identifies combinations of six primer regions for basic LAMP signatures, or combinations of eight primer regions for LAMP signatures with loop primers, which can be used as LAMP signatures. The identified primers are conserved among target organism sequences. Primer combinations are optimized based on lengths, melting temperatures, and spacing among primer sites. We compare LAMP signature candidates for Staphylococcus aureus created both by LAVA and by PrimerExplorer. We also include signatures from a sample run targeting all strains of Mycobacterium tuberculosis. Conclusions We have designed and demonstrated new software for identifying signature candidates appropriate for LAMP assays. The software is available for download at http://lava-dna.googlecode.com/.

Lava Simulation and Risk Assessment During The July 2001 Etnean Eruption

Science.gov (United States)

Crisci, G. M.; di Gregorio, S.; Rongo, R.; Spataro, W.

SCIARA, a two-dimensional cellular automata model for the simulation of lava flows, has been in the past validated on real cases of Etnean eruptions. Its lastest release, SCIARA-hex1 was applied on the 1991-93 Etnean eruption in validation phase. The simulation results are satisfying within limits to forecast the lava flow path. The pre- sented version isnSt more sophisticated than the previous version, because it does- nSt manage lava layers at different temperatures in the same cell and their distinct outflows, but its speed permitted to generate a large number of scenarios in quickly evolving emergence situation. Moreover, SCIARA-hex1 was applied recently during the Etnean crisis in the summer of 2001, when a new eruption threatened the town of Nicolosi. The emission, that started on July 18th 2001, represented during the cri- sis the main danger for the towns of Nicolosi and Belpasso; it was, in its maximum extension, only four kilometres away from the Nicolosi. The study was done in collab- oration with the Italian National Institute of Geophysics and Vulcanology of Catania. This Sreal timeT application proved that SCIARA is a reliable and flexible tool for & cedil;forecasting lava flow paths and for assessing hazard in the Etnean area, besides being useful for the creation of real scenarios. In SCIARA, lava flows are viewed as a dy- namic system based on local interactions with discrete time and space, where space is represented by hexagonal cells, which specification (state) describes the character- istics (substates) of the corresponding piece of space. The neighbouring of a cell c, specifying the interacting cells, is given by its adjacent cells. The computation of the new values of the substates in the cells gives the evolution of the phenomenon. The distribution of the lava is crucial in the definition of the model: it is based on a proce- dure of minimisation of the differences. Moreover, with respect to previous SCIARA models, spurious symmetries

Shatter Complex Formation in the Twin Craters Lava Flow, Zuni-Bandera Field, New Mexico

Science.gov (United States)

von Meerscheidt, H. C.; Bleacher, J. E.; Brand, B. D.; deWet, A.; Samuels, R.; Hamilton, C.; Garry, W. B.; Bandfield, J. L.

2013-12-01

Lava channels, tubes and sheets are transport structures that deliver flowing lava to a flow front. The type of structure can vary within a flow field and evolve throughout an eruption. The 18.0 × 1.0 ka Twin Craters lava flow in the Zuni-Bandera lava field provides a unique opportunity to study morphological changes of a lava flow partly attributable to interaction with a topographic obstacle. Facies mapping and airborne image analysis were performed on an area of the Twin Craters flow that includes a network of channels, lava tubes, shatter features, and disrupted pahoehoe flows surrounding a 45 m tall limestone bluff. The bluff is 1000 m long (oriented perpendicular to flow.) The general flow characteristics upstream from the bluff include smooth, lobate pahoehoe flows and a >2.5 km long lava tube (see Samuels et al., this meeting.) Emplacement characteristics change abruptly where the flow encountered the bluff, to include many localized areas of disrupted pahoehoe and several pahoehoe-floored depressions. Each depression is fully or partly surrounded by a raised rim of blocky material up to 4 m higher than the surrounding terrain. The rim is composed of 0.05 - 4 m diameter blocks, some of which form a breccia that is welded by lava, and some of which exhibit original flow textures. The rim-depression features are interpreted as shatter rings based on morphological similarity to those described by Orr (2011.Bul Volcanol.73.335-346) in Hawai';i. Orr suggests that shatter rings develop when fluctuations in the lava supply rate over-pressurize the tube, causing the tube roof to repeatedly uplift and subside. A rim of shattered blocks and breccias remains surrounding the sunken tube roof after the final lava withdraws from the system. One of these depressions in the Twin Craters flow is 240 m wide and includes six mounds of shattered material equal in height to the surrounding undisturbed terrain. Several mounds have depressed centers floored with rubbly pahoehoe

Limited role for thermal erosion by turbulent lava in proximal Athabasca Valles, Mars

Science.gov (United States)

Cataldo, Vincenzo; Williams, David A.; Dundas, Colin M.; Kestay, Laszlo P.

2015-01-01

The Athabasca Valles flood lava is among the most recent (Mars and was probably emplaced turbulently. The Williams et al. (2005) model of thermal erosion by lava has been applied to what we term “proximal Athabasca,” the 75 km long upstream portion of Athabasca Valles. For emplacement volumes of 5000 and 7500 km3and average flow thicknesses of 20 and 30 m, the duration of the eruption varies between ~11 and ~37 days. The erosion of the lava flow substrate is investigated for three eruption temperatures (1270°C, 1260°C, and 1250°C), and volatile contents equivalent to 0–65 vol % bubbles. The largest erosion depths of ~3.8–7.5 m are at the lava source, for 20 m thick and bubble-free flows that erupted at their liquidus temperature (1270°C). A substrate containing 25 vol % ice leads to maximum erosion. A lava temperature 20°C below liquidus reduces erosion depths by a factor of ~2.2. If flow viscosity increases with increasing bubble content in the lava, the presence of 30–50 vol % bubbles leads to erosion depths lower than those relative to bubble-free lava by a factor of ~2.4. The presence of 25 vol % ice in the substrate increases erosion depths by a factor of 1.3. Nevertheless, modeled erosion depths, consistent with the emplacement volume and flow duration constraints, are far less than the depth of the channel (~35–100 m). We conclude that thermal erosion does not appear to have had a major role in excavating Athabasca Valles.

Sulphur isotopes in a metamorphogenic gold deposit, Macraes mine, Otago Schist, New Zealand

International Nuclear Information System (INIS)

Craw, D.; Hall, A.J.; Fallick, A.E.; Boyce, A.J.

1995-01-01

The Macraes gold quartz vein deposit, New Zealand, is located in a shear zone cutting greenschist facies metasediments of the Otago Schist. The deposit has been interpreted as being metamorphogenic in origin as there is no evidence for coeval magmatic activity in the Otago Schist orogen. The immediate host rock at the Macraes deposit is pyritic (δ 34 S = -2.7 to -1.3 per mil ) and locally weakly graphitic schist, a rare rock type in the Otago Schist. Sulphur isotope analyses of pyrite and arsenopyrite extracts from auriferous veins and wall-rock schist provide a similar narrow range in δ 34 S values, from -3.0 to -1.0 per mil (n=9). The lack of isotopically depleted sulphur, the narrow range in values, and the replacement sulphide textures help discount a primary bacteriogenic origin for host-rock sulphide. Sulphide in both veins and wall rock is of hydrothermal origin. Sulphides in metasediments and metavolcanics elsewhere in the Otago Schist have δ 34 S in the narrow range -6 to +6 per mil. The sulphur isotope data are consistent with origin of hydrothermal sulphur within the metamorphic pile but provide no constraint on specific rock types which contributed the sulphur to the hydrothermal fluid. The study demonstrates that sulphur isotopic signatures near zero per mil can arise without any direct magmatic input into the mineralisation process. (author). 34 refs., 2 figs., 1 tab

Origin of organic sulphur compounds and sulphur-containing high molecular weight substances in sediments and immature crude oils

NARCIS (Netherlands)

Sinninghe Damsté, J.S.; Rijpstra, W.I.C.; Leeuw, J.W. de; Schenck, P.A.

1988-01-01

The distribution patterns of Organic Sulphur Compounds (OSC), occurring in certain sediments and immature crude oils, were compared with those of the corresponding hydrocarbons. Because of the complexity of the OSC mixtures, they were desulphurized to hydrocarbons (n-alkanes, isoprenoid alkanes,

Extensive young silicic volcanism produces large deep submarine lava flows in the NE Lau Basin

Science.gov (United States)

Embley, Robert W.; Rubin, Kenneth H.

2018-04-01

New field observations reveal that extensive (up to 402 km2) aphyric, glassy dacite lavas were erupted at multiple sites in the recent past in the NE Lau basin, located about 200 km southwest of Samoa. This discovery of volumetrically significant and widespread submarine dacite lava flows extends the domain for siliceous effusive volcanism into the deep seafloor. Although several lava flow fields were discovered on the flank of a large silicic seamount, Niuatahi, two of the largest lava fields and several smaller ones ("northern lava flow fields") were found well north of the seamount. The most distal portion of the northernmost of these fields is 60 km north of the center of Niuatahi caldera. We estimate that lava flow lengths from probable eruptive vents to the distal ends of flows range from a few km to more than 10 km. Camera tows on the shallower, near-vent areas show complex lava morphology that includes anastomosing tube-like pillow flows and ropey surfaces, endogenous domes and/or ridges, some with "crease-like" extrusion ridges, and inflated lobes with extrusion structures. A 2 × 1.5 km, 30-m deep depression could be an eruption center for one of the lava flow fields. The Lau lava flow fields appear to have erupted at presumptive high effusion rates and possibly reduced viscosity induced by presumptive high magmatic water content and/or a high eruption temperature, consistent with both erupted composition ( 66% SiO2) and glassy low crystallinity groundmass textures. The large areal extent (236 km2) and relatively small range of compositional variation ( σ = 0.60 for wt% Si02%) within the northern lava flow fields imply the existence of large, eruptible batches of differentiated melt in the upper mantle or lower crust of the NE Lau basin. At this site, the volcanism could be controlled by deep crustal fractures caused by the long-term extension in this rear-arc region. Submarine dacite flows exhibiting similar morphology have been described in ancient

Phreatic explosions during basaltic fissure eruptions: Kings Bowl lava field, Snake River Plain, USA

Science.gov (United States)

Hughes, Scott S.; Kobs Nawotniak, Shannon E.; Sears, Derek W. G.; Borg, Christian; Garry, William Brent; Christiansen, Eric H.; Haberle, Christopher W.; Lim, Darlene S. S.; Heldmann, Jennifer L.

2018-02-01

Physical and compositional measurements are made at the 7 km-long ( 2200 years B.P.) Kings Bowl basaltic fissure system and surrounding lava field in order to further understand the interaction of fissure-fed lavas with phreatic explosive events. These assessments are intended to elucidate the cause and potential for hazards associated with phreatic phases that occur during basaltic fissure eruptions. In the present paper we focus on a general understanding of the geological history of the site. We utilize geospatial analysis of lava surfaces, lithologic and geochemical signatures of lava flows and explosively ejected blocks, and surveys via ground observation and remote sensing. Lithologic and geochemical signatures readily distinguish between Kings Bowl and underlying pre-Kings Bowl lava flows, both of which comprise phreatic ejecta from the Kings Bowl fissure. These basalt types, as well as neighboring lava flows from the contemporaneous Wapi lava field and the older Inferno Chasm vent and outflow channel, fall compositionally within the framework of eastern Snake River Plain olivine tholeiites. Total volume of lava in the Kings Bowl field is estimated to be 0.0125 km3, compared to a previous estimate of 0.005 km3. The main (central) lava lake lost a total of 0.0018 km3 of magma by either drain-back into the fissure system or breakout flows from breached levees. Phreatic explosions along the Kings Bowl fissure system occurred after magma supply was cut off, leading to fissure evacuation, and were triggered by magma withdrawal. The fissure system produced multiple phreatic explosions and the main pit is accompanied by others that occur as subordinate pits and linear blast corridors along the fissure. The drop in magma supply and the concomitant influx of groundwater were necessary processes that led to the formation of Kings Bowl and other pits along the fissure. A conceptual model is presented that has relevance to the broader range of low-volume, monogenetic

Lava tubes and aquifer vulnerability in the upper Actopan River basin, Veracruz, México

Science.gov (United States)

Espinasa-Pereña, R.; Delgado Granados, H.

2011-12-01

Rapid infiltration leads to very dry conditions on the surface of some volcanic terrains, with large allogenic streams sometimes sinking underground upon reaching a lava flow. Aquifers in lava flows tend to be heterogeneous and discontinuous, generally unconfined and fissured, and have high transmissivity. Springs associated with basalts may be very large but are typically restricted to lava-flow margins. Concern has been expressed regarding the potential for lava-tube caves to facilitate groundwater contamination similar to that afflicting some karst aquifers (Kempe et al., 2003; Kiernan et al., 2002; Halliday 2003). The upper Actopan River basin is a series of narrow valleys excavated in Tertiary volcanic brechias. Several extensive Holocene basaltic tube-fed lava flows have partially filled these valleys. The youngest and longest flow originates at El Volcancillo, a 780 ybP monogenetic volcano. It is over 50 km long, and was fed through a major master tube, the remains of which form several lava-tube caves (Gassos and Espinasa-Pereña, 2008). Another tube-fed flow initiates at a vent at the bottom of Barranca Huichila and can be followed for 7 km to where it is covered by the Volcancillo flow. The Huichila River is captured by this system of lava tubes and can be followed through several underground sections. In dry weather the stream disappears at a sump in one of these caves, although during hurricanes it overflows the tube, floods the Tengonapa plain, and finally sinks through a series of skylights into the master tube of the Volcancillo flow. Near villages, the cave entrances are used as trash dumps, which are mobilized during floods. These include household garbage, organic materials associated with agriculture and even medical supplies. This is a relatively recent phenomenon, caused by population growth and the building of houses above the lava flows. The water resurges at El Descabezadero, gushing from fractures in the lava above the underlying brechias

Thermal stability studies on atomically clean and sulphur passivated InGaAs surfaces

Energy Technology Data Exchange (ETDEWEB)

Chauhan, Lalit; Hughes, Greg [School of Physical Sciences, Dublin City University, Glasnevin, Dublin 9 (Ireland)

2013-03-15

High resolution synchrotron radiation core level photoemission measurements have been used to study the high temperature stability of sulphur passivated InGaAs surfaces and comparisons made with atomically clean surfaces subjected to the same annealing temperatures. Sulphur passivation of clean InGaAs surfaces prepared by the thermal removal of an arsenic capping layer was carried out using an in situ molecular sulphur treatment in ultra high vacuum. The elemental composition of the surfaces of these materials was measured at a series of annealing temperatures up to 530 C. Following a 480 C anneal In:Ga ratio was found to have dropped by 33% on sulphur passivated surface indicating a significant loss of indium, while no drop in indium signal was recorded at this temperature on the atomically InGaAs surface. No significant change in the As surface concentration was measured at this temperature. These results reflect the reduced thermal stability of the sulphur passivated InGaAs compared to the atomically clean surface which has implications for device fabrication. (Copyright copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Geochemistry of axial seamount lavas: Magmatic relationship between the Cobb Hotspot and the Juan de Fuca Ridge

Science.gov (United States)

Rhodes, J. M.; Morgan, C.; Liias, R. A.

1990-08-01

Axial Seamount, located along the central portion of the Juan de Fuca Ridge axis and at the eastern end of the Cobb-Eickelberg Seamount Chain, is the current center of the Cobb Hotspot. The Axial Seamount lavas are transitional between N-type and E-type mid-ocean ridge basalt (MORB), characteristics that they share with lavas along the rest of the Juan de Fuca Ridge. There are, however, subtle, but distinct, differences between the seamount lavas and those of the adjoining ridge segments. These include higher Na2O, CaO, and Sr at a given MgO content and lower silica saturation in the seamount lavas as compared with the ridge lavas. Lava chemistry and bathymetry indicate that Axial Seamount is a discrete volcanic unit, with a more productive shallow magmatic plumbing system separate from the adjacent ridge segments. These high magma supply rates have sustained a continuously replenished, steady state magma reservoir that has erupted remarkably homogeneous lavas over a long time period. Despite this classic association of spreading center and hotspot volcanic activity, there is no evidence in the lavas for geochemical or isotopic enrichment typical of hotspot or mantle plume activity. The differences in composition between the Axial Seamount lavas and the Juan de Fuca Ridge lavas are attributed to melting processes rather than to any fundamental differences in their mantle source compositions. The higher magma production rates, higher Sr, and lower silica saturation in the seamount lavas relative to the ridge lavas are thought to be a consequence of melt initiation at greater depths. The melting column producing the seamount lavas is thought to be initiated in the stability field of spinel peridotite, whereas the ridge lavas are produced from a melting column initiated at shallower levels, possibly within or close to the stability field of plagioclase peridotite. Implicit in this interpretation is the conclusion that the Juan de Fuca Ridge lavas, and by analogy most

Nitrogen and Sulphur Relations in Effecting Yield and Quality of Cereals and Oilseed Crops

Directory of Open Access Journals (Sweden)

B.K. Nad

2001-01-01

Full Text Available Nitrogen and sulphur, both vital structural elements, are especially needed for the synthesis of proteins and oils. Investigations revealed the required application of sulphur is one half to one third the amount of nitrogen, and the ratio becomes narrower in mustard (Brassica juncea L., followed by wheat and rice. The efficiency of an increased level of nitrogen required a proportionately higher amount of sulphur. A critical investigation on the effective utilization of applied vis-à-vis absorbed nitrogen in wheat and mustard envisaged accumulation of NO3-N in vegetative parts when sulphur remained proportionately low. Application of sulphur hastened the chemical reduction of absorbed NO3– for its effective utilization. The effect was more pronounced in mustard than in wheat. Easily available forms of sulphur, like ammonium sulphate and gypsum, as compared to pyrite or elemental sulphur, maintained adequate N to S ratio in rice, resulting in a reduction in the percent of unfilled grain, a major consideration in rice yield. A narrow N to S ratio, with both at higher levels, increased the oil content but raised the saponification value of the oil, a measure of free fatty acids. Whereas, a proportionately narrow N to S ratio at moderate dose resulted in adequately higher seed and oil yield with relatively low saponification value, associated with increased iodine value of the oil, indicating respectively low free fatty acids and higher proportion of unsaturated fatty acids, an index for better quality of the oil.

Modified sulphur cement: A low porosity encapsulation material for low, medium and alpha waste

International Nuclear Information System (INIS)

Dalen, A. van; Rijpkema, J.E.

1989-01-01

Modified sulphur cement, available under the trade name Chement 2000, is a thermoplastic candidate material for the matrix of low, intermediate and alpha radioactive waste. The main source of sulphur is the desulphurization of fossil fuels. In view of the future increase of this product a modified compound of sulphur has been developed at the US Bureau of Mines. Modified sulphur cement as matrix material has properties in common with Portland or blast furnace cement and bitumen. The mechanical strength is comparable to hydraulic cement products. The process to incorporate waste materials is identical to bitumization. The leachability and the resistance to attack by chemicals is nearly the same as for bituminized products. This study showed also that the radiation resistance is high without radiolytic gas production and without change in dimensions (swelling). The rigidity of the matrix is a disadvantage when internal pressures are built up. The thermal conductivity and the heat of combustion of sulphur is low resulting in slow damage to the waste form under fire conditions, even when the temperature of self ignition in air is 220 0 C. The low leachability, the very slow effective diffusion of H 2 O and HTO, and the low permeability is due to the small pore diameters in the modified sulphur matrix. The loading capacity of modified sulphur cement depends on grain size and distribution and is for ungraded ashes, precipitates, dried sludges, etc., in the order of 40-50% of weight. The price of Chement 2000 per tonne is equal to those of blown bitumen

Isotopic equilibria between sulphur solute species at high temperature

International Nuclear Information System (INIS)

Robinson, B.W.

1978-01-01

Sulphur solute species in ore solutions and geothermal discharges include HSO 4 - , SO 4 2- , H 2 S, and HS - , as well as the ion-paired species, NaHS 0 , NaHSO 4 - and Na 2 SO 4 0 . Observed sulphate-sulphide fractionation factors and the rates of attainment of isotopic equilibrium are likely to depend on the nature of the sulphur species actually taking part in these isotopic equilibria. Preliminary experiments in alkaline solution (pH 10.1 at 20 0 C) were carried out in a gold cell. No significant isotope fractionation was observed between the SO 4 2- and HS - in 29 days at 200 0 C, 63days at 300 0 C, or 90 days at 250 0 C. However, similar experiments at 350 0 C in sealed gold capsules at room temperature pH 8.5 showed slow exchange(t( 1 / 2 ) was calculated to be 510 days for the SO 4 2- -HS - exchange reaction using the theoretical fractionation of 20.2 0 / 00 ). The addition of NaCl appeared to have no affect on the exchange. However, pH strongly controls the reaction rate, and exchange probably involves H 2 S and the HSO 4 - ion. Additional preliminary experiments were conducted with a fivefold increase in the sulphur concentration; a decrease in t( 1 / 2 ) to 142 days resulted. Some inter-relationship between sulphur concentration and exchange rate thus exists. The important controlling parameters of isotope exchange (temperature, pH, and ΣS) can be seen to have influenced exchange in natural systems.(auth.)

LAV@HAZARD: a Web-GIS Framework for Real-Time Forecasting of Lava Flow Hazards

Science.gov (United States)

Del Negro, C.; Bilotta, G.; Cappello, A.; Ganci, G.; Herault, A.

2014-12-01

Crucial to lava flow hazard assessment is the development of tools for real-time prediction of flow paths, flow advance rates, and final flow lengths. Accurate prediction of flow paths and advance rates requires not only rapid assessment of eruption conditions (especially effusion rate) but also improved models of lava flow emplacement. Here we present the LAV@HAZARD web-GIS framework, which combines spaceborne remote sensing techniques and numerical simulations for real-time forecasting of lava flow hazards. By using satellite-derived discharge rates to drive a lava flow emplacement model, LAV@HAZARD allows timely definition of parameters and maps essential for hazard assessment, including the propagation time of lava flows and the maximum run-out distance. We take advantage of the flexibility of the HOTSAT thermal monitoring system to process satellite images coming from sensors with different spatial, temporal and spectral resolutions. HOTSAT was designed to ingest infrared satellite data acquired by the MODIS and SEVIRI sensors to output hot spot location, lava thermal flux and discharge rate. We use LAV@HAZARD to merge this output with the MAGFLOW physics-based model to simulate lava flow paths and to update, in a timely manner, flow simulations. Thus, any significant changes in lava discharge rate are included in the predictions. A significant benefit in terms of computational speed was obtained thanks to the parallel implementation of MAGFLOW on graphic processing units (GPUs). All this useful information has been gathered into the LAV@HAZARD platform which, due to the high degree of interactivity, allows generation of easily readable maps and a fast way to explore alternative scenarios. We will describe and demonstrate the operation of this framework using a variety of case studies pertaining to Mt Etna, Sicily. Although this study was conducted on Mt Etna, the approach used is designed to be applicable to other volcanic areas around the world.

Assessment of hydrology, water quality, and trace elements in selected placer-mined creeks in the birch creek watershed near central, Alaska, 2001-05

Science.gov (United States)

Kennedy, Ben W.; Langley, Dustin E.

2007-01-01

Executive Summary The U.S. Geological Survey, in cooperation with the Bureau of Land Management, completed an assessment of hydrology, water quality, and trace-element concentrations in streambed sediment of the upper Birch Creek watershed near Central, Alaska. The assessment covered one site on upper Birch Creek and paired sites, upstream and downstream from mined areas, on Frying Pan Creek and Harrison Creek. Stream-discharge and suspended-sediment concentration data collected at other selected mined and unmined sites helped characterize conditions in the upper Birch Creek watershed. The purpose of the project was to provide the Bureau of Land Management with baseline information to evaluate watershed water quality and plan reclamation efforts. Data collection began in September 2001 and ended in September 2005. There were substantial geomorphic disturbances in the stream channel and flood plain along several miles of Harrison Creek. Placer mining has physically altered the natural stream channel morphology and removed streamside vegetation. There has been little or no effort to re-contour waste rock piles. During high-flow events, the abandoned placer-mine areas on Harrison Creek will likely contribute large quantities of sediment downstream unless the mined areas are reclaimed. During 2004 and 2005, no substantial changes in nutrient or major-ion concentrations were detected in water samples collected upstream from mined areas compared with water samples collected downstream from mined areas on Frying Pan Creek and Harrison Creek that could not be attributed to natural variation. This also was true for dissolved oxygen, pH, and specific conductance-a measure of total dissolved solids. Sample sites downstream from mined areas on Harrison Creek and Frying Pan Creek had higher median suspended-sediment concentrations, by a few milligrams per liter, than respective upstream sites. However, it is difficult to attach much importance to the small downstream increase

Prediction of sulphur content in the industrial hydrotreatment process

Energy Technology Data Exchange (ETDEWEB)

Lukec, Ivana; Lukec, Darko [Model d.o.o, Pazinska 36, 10110 Zagreb (Croatia); Sertic-Bionda, Katica [Faculty of Chemical Engineering and Technology, Marulicev trg 19, 10000, Zagreb (Croatia)

2008-03-15

The artificial neural network models were developed to determine sulphur content in the hydrotreatment product. Two models for two different types of feed were developed: light gas oil and vacuum gas oil. The developed ANN models use 6 input variables that are continuously measured in the process and are in accordance with the engineering knowledge and thermodynamics of hydrotreatment processes. Given models show good predictability of sulphur content in the hydrotreatment product and are, therefore, used in practice for continuous monitoring and optimization. This kind of application can be easily developed in any other hydrotreatment process with the available adequate historical data. (author)

Simultaneous analysis of gaseous and particulate sulphur in the atmosphere by x-ray fluorescence spectrometry

International Nuclear Information System (INIS)

Matsuda, Yatsuka; Mamuro, Tetsuo

1975-01-01

An analytical technique for the simultaneous measurements of the atmospheric concentrations of SO 2 gas and sulphur absorbed by aerosol particles has been developed. Aerosol particles are collected on membrane filter and at the same time SO 2 gas is captured on alkali impregnated filter. The sulphur content in each filter is measured by an energy dispersive X -ray fluorescence spectrometer consisting of a Si(Li) semiconductor detector connected to a multi-channel pulse height analyzer and an excitation source of 55 Fe. Two methods are acceptable for the determination of the sulphur content in impregnated filter by X-ray fluorescence analysis. In the first method X-ray fluorescence analysis is made after the collected sulphur gas diffused and distributed uniformly enough throughout the filter, and in the second method X-ray fluorescence analysis gas to be finished before the diffusion of the collected sulphur becomes appreciable. (author)

Water quality of the Swatara Creek Basin, PA

Science.gov (United States)

McCarren, Edward F.; Wark, J.W.; George, J.R.

1964-01-01

The Swatara Creek of the Susquehanna River Basin is the farthest downstream sub-basin that drains acid water (pH of 4.5 or less) from anthracite coal mines. The Swatara Creek drainage area includes 567 square miles of parts of Schuylkill, Berks, Lebanon, and Dauphin Counties in Pennsylvania.To learn what environmental factors and dissolved constituents in water were influencing the quality of Swatara Creek, a reconnaissance of the basin was begun during the summer of 1958. Most of the surface streams and the wells adjacent to the principal tributaries of the Creek were sampled for chemical analysis. Effluents from aquifers underlying the basin were chemically analyzed because ground water is the basic source of supply to surface streams in the Swatara Creek basin. When there is little runoff during droughts, ground water has a dominating influence on the quality of surface water. Field tests showed that all ground water in the basin was non-acidic. However, several streams were acidic. Sources of acidity in these streams were traced to the overflow of impounded water in unworked coal mines.Acidic mine effluents and washings from coal breakers were detected downstream in Swatara Creek as far as Harper Tavern, although the pH at Harper Tavern infrequently went below 6.0. Suspended-sediment sampling at this location showed the mean daily concentration ranged from 2 to 500 ppm. The concentration of suspended sediment is influenced by runoff and land use, and at Harper Tavern it consisted of natural sediments and coal wastes. The average daily suspended-sediment discharge there during the period May 8 to September 30, 1959, was 109 tons per day, and the computed annual suspended-sediment load, 450 tons per square mile. Only moderate treatment would be required to restore the quality of Swatara Creek at Harper Tavern for many uses. Above Ravine, however, the quality of the Creek is generally acidic and, therefore, of limited usefulness to public supplies, industries and

Modeling risk assessment for nuclear processing plants with LAVA

International Nuclear Information System (INIS)

Smith, S.T.; Tisinger, R.M.

1988-01-01

Using the Los Alamos Vulnerability and Risk Assessment (LAVA) methodology, the authors developed a model for assessing risks associated with nuclear processing plants. LAVA is a three-part systematic approach to risk assessment. The first part is the mathematical methodology; the second is the general personal computer-based software engine; and the third is the application itself. The methodology provides a framework for creating applications for the software engine to operate upon; all application-specific information is data. Using LAVA, the authors build knowledge-based expert systems to assess risks in applications systems comprising a subject system and a safeguards system. The subject system model is sets of threats, assets, and undesirable outcomes. The safeguards system model is sets of safeguards functions for protecting the assets from the threats by preventing or ameliorating the undesirable outcomes, sets of safeguards subfunctions whose performance determine whether the function is adequate and complete, and sets of issues, appearing as interactive questionnaires, whose measures (in both monetary and linguistic terms) define both the weaknesses in the safeguards system and the potential costs of an undesirable outcome occurring

Petrogenesis of Rinjani Post-1257-Caldera-Forming-Eruption Lava Flows

Directory of Open Access Journals (Sweden)

Heryadi Rachmat

2016-06-01

Full Text Available DOI:10.17014/ijog.3.2.107-126After the catastrophic 1257 caldera-forming eruption, a new chapter of Old Rinjani volcanic activity beganwith the appearance of Rombongan and Barujari Volcanoes within the caldera. However, no published petrogeneticstudy focuses mainly on these products. The Rombongan eruption in 1944 and Barujari eruptions in pre-1944, 1966,1994, 2004, and 2009 produced basaltic andesite pyroclastic materials and lava flows. A total of thirty-one sampleswere analyzed, including six samples for each period of eruption except from 2004 (only one sample. The sampleswere used for petrography, whole-rock geochemistry, and trace and rare earth element analyses. The Rombonganand Barujari lavas are composed of calc-alkaline and high K calc-alkaline porphyritic basaltic andesite. The magmashows narrow variation of SiO2 content that implies small changes during its generation. The magma that formedRombongan and Barujari lavas is island-arc alkaline basalt. Generally, data show that the rocks are enriched in LargeIon Lithophile Elements (LILE: K, Rb, Ba, Sr, and Ba and depleted in High Field Strength Elements (HFSE: Y, Ti,and Nb which are typically a suite from a subduction zone. The pattern shows a medium enrichment in Light REEand relatively depleted in Heavy REE. The processes are dominantly controlled by fractional crystallization andmagma mixing. All of the Barujari and Rombongan lavas would have been produced by the same source of magmawith little variation in composition caused by host rock filter process. New flux of magma would likely have occurredfrom pre-1944 until 2009 period that indicates slightly decrease and increase of SiO2 content. The Rombongan andBarujari lava generations show an arc magma differentiation trend.

Geochemistry of southern Pagan Island lavas, Mariana arc: The role of subduction zone processes

Science.gov (United States)

Marske, J.P.; Pietruszka, A.J.; Trusdell, F.A.; Garcia, M.O.

2011-01-01

New major and trace element abundances, and Pb, Sr, and Nd isotopic ratios of Quaternary lavas from two adjacent volcanoes (South Pagan and the Central Volcanic Region, or CVR) located on Pagan Island allow us to investigate the mantle source (i.e., slab components) and melting dynamics within the Mariana intra-oceanic arc. Geologic mapping reveals a pre-caldera (780-9.4ka) and post-caldera (<9.4ka) eruptive stage for South Pagan, whereas the eruptive history of the older CVR is poorly constrained. Crystal fractionation and magma mixing were important crustal processes for lavas from both volcanoes. Geochemical and isotopic variations indicate that South Pagan and CVR lavas, and lavas from the northern volcano on the island, Mt. Pagan, originated from compositionally distinct parental magmas due to variations in slab contributions (sediment and aqueous fluid) to the mantle wedge and the extent of mantle partial melting. A mixing model based on Pb and Nd isotopic ratios suggests that the average amount of sediment in the source of CVR (~2.1%) and South Pagan (~1.8%) lavas is slightly higher than Mt. Pagan (~1.4%) lavas. These estimates span the range of sediment-poor Guguan (~1.3%) and sediment-rich Agrigan (~2.0%) lavas for the Mariana arc. Melt modeling demonstrates that the saucer-shaped normalized rare earth element (REE) patterns observed in Pagan lavas can arise from partial melting of a mixed source of depleted mantle and enriched sediment, and do not require amphibole interaction or fractionation to depress the middle REE abundances of the lavas. The modeled degree of mantle partial melting for Agrigan (2-5%), Pagan (3-7%), and Guguan (9-15%) lavas correlates with indicators of fluid addition (e.g., Ba/Th). This relationship suggests that the fluid flux to the mantle wedge is the dominant control on the extent of partial melting beneath Mariana arc volcanoes. A decrease in the amount of fluid addition (lower Ba/Th) and extent of melting (higher Sm/Yb), and

77 FR 10960 - Drawbridge Operation Regulation; Snake Creek, Islamorada, FL

Science.gov (United States)

2012-02-24

... Operation Regulation; Snake Creek, Islamorada, FL AGENCY: Coast Guard, DHS. ACTION: Notice of temporary... deviation from the regulation governing the operation of Snake Creek Bridge, mile 0.5, across Snake Creek... schedule of Snake Creek Bridge in Islamorada, Florida. This deviation will result in the bridge opening...

Lava lake level as a gauge of magma reservoir pressure and eruptive hazard

Science.gov (United States)

Patrick, Matthew R.; Anderson, Kyle R.; Poland, Michael P.; Orr, Tim R.; Swanson, Donald A.

2015-01-01

Forecasting volcanic activity relies fundamentally on tracking magma pressure through the use of proxies, such as ground surface deformation and earthquake rates. Lava lakes at open-vent basaltic volcanoes provide a window into the uppermost magma system for gauging reservoir pressure changes more directly. At Kīlauea Volcano (Hawaiʻi, USA) the surface height of the summit lava lake in Halemaʻumaʻu Crater fluctuates with surface deformation over short (hours to days) and long (weeks to months) time scales. This correlation implies that the lake behaves as a simple piezometer of the subsurface magma reservoir. Changes in lava level and summit deformation scale with (and shortly precede) changes in eruption rate from Kīlauea's East Rift Zone, indicating that summit lava level can be used for short-term forecasting of rift zone activity and associated hazards at Kīlauea.

33 CFR 117.917 - Battery Creek.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Battery Creek. 117.917 Section 117.917 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements South Carolina § 117.917 Battery Creek. The draw of...

33 CFR 117.324 - Rice Creek.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Rice Creek. 117.324 Section 117.324 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Florida § 117.324 Rice Creek. The CSX Railroad Swingbridge, mile...

33 CFR 117.231 - Brandywine Creek.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Brandywine Creek. 117.231 Section 117.231 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Delaware § 117.231 Brandywine Creek. The draw of the...

Lava Eruption and Emplacement: Using Clues from Hawaii and Iceland to Probe the Lunar Past

Science.gov (United States)

Needham, Debra Hurwitz; Hamilton, C. W.; Bleacher, J. E.; Whelley, P. L.; Young, K. E.; Scheidt, S. P.; Richardson, J. A.; Sutton, S. S.

2017-01-01

Investigating recent eruptions on Earth is crucial to improving understanding of relationships between eruption dynamics and final lava flow morphologies. In this study, we investigated eruptions in Holuhraun, Iceland, and Kilauea, Hawaii to gain insight into the lava dynamics near the source vent, the initiation of lava channels, and the origin of down-channel features. Insights are applied to Rima Bode on the lunar nearside to deduce the sequence of events that formed this lunar sinuous rille system. These insights are crucial to correctly interpreting whether the volcanic features associated with Rima Bode directly relate to eruption conditions at the vent and, thus, can help us understand those eruption dynamics, or, alternatively, whether the features formed as a result of more localized influences on lava flow dynamics. For example, if the lava channel developed early in the eruption and was linked to pulses in vent activity, its morphology can be analyzed to interpret the flux and duration of the eruption. Conversely, if the lava channel initiated late in the eruption as the result of a catastrophic breaching of lava that had previously pooled within the vent [e.g., 1], then the final channel morphology will not indicate eruption dynamics but rather local dynamics associated with that breach event. Distinguishing between these two scenarios is crucial for correctly interpreting the intensity and duration of volcanic history on the Moon.

Lava-flow hazard on the SE flank of Mt. Etna (Southern Italy)

Science.gov (United States)

Crisci, G. M.; Iovine, G.; Di Gregorio, S.; Lupiano, V.

2008-11-01

A method for mapping lava-flow hazard on the SE flank of Mt. Etna (Sicily, Southern Italy) by applying the Cellular Automata model SCIARA -fv is described, together with employed techniques of calibration and validation through a parallel Genetic Algorithm. The study area is partly urbanised; it has repeatedly been affected by lava flows from flank eruptions in historical time, and shows evidence of a dominant SSE-trending fracture system. Moreover, a dormant deep-seated gravitational deformation, associated with a larger volcano-tectonic phenomenon, affects the whole south-eastern flank of the volcano. The Etnean 2001 Mt. Calcarazzi lava-flow event has been selected for model calibration, while validation has been performed by considering the 2002 Linguaglossa and the 1991-93 Valle del Bove events — suitable data for back analysis being available for these recent eruptions. Quantitative evaluation of the simulations, with respect to the real events, has been performed by means of a couple of fitness functions, which consider either the areas affected by the lava flows, or areas and eruption duration. Sensitivity analyses are in progress for thoroughly evaluating the role of parameters, topographic input data, and mesh geometry on model performance; though, preliminary results have already given encouraging responses on model robustness. In order to evaluate lava-flow hazard in the study area, a regular grid of n.340 possible vents, uniformly covering the study area and located at 500 m intervals, has been hypothesised. For each vent, a statistically-significant number of simulations has been planned, by adopting combinations of durations, lava volumes, and effusion-rate functions, selected by considering available volcanological data. Performed simulations have been stored in a GIS environment for successive analyses and map elaboration. Probabilities of activation, empirically based on past behaviour of the volcano, can be assigned to each vent of the grid, by

Modeling steam pressure under martian lava flows

Science.gov (United States)

Dundas, Colin M.; Keszthelyi, Laszlo P.

2013-01-01

Rootless cones on Mars are a valuable indicator of past interactions between lava and water. However, the details of the lava–water interactions are not fully understood, limiting the ability to use these features to infer new information about past water on Mars. We have developed a model for the pressurization of a dry layer of porous regolith by melting and boiling ground ice in the shallow subsurface. This model builds on previous models of lava cooling and melting of subsurface ice. We find that for reasonable regolith properties and ice depths of decimeters, explosive pressures can be reached. However, the energy stored within such lags is insufficient to excavate thick flows unless they draw steam from a broader region than the local eruption site. These results indicate that lag pressurization can drive rootless cone formation under favorable circumstances, but in other instances molten fuel–coolant interactions are probably required. We use the model results to consider a range of scenarios for rootless cone formation in Athabasca Valles. Pressure buildup by melting and boiling ice under a desiccated lag is possible in some locations, consistent with the expected distribution of ice implanted from atmospheric water vapor. However, it is uncertain whether such ice has existed in the vicinity of Athabasca Valles in recent history. Plausible alternative sources include surface snow or an aqueous flood shortly before the emplacement of the lava flow.

Emplacement dynamics and lava field evolution of the flood basalt eruption at Holuhraun, Iceland: Observations from field and remote sensing data

Science.gov (United States)

Pedersen, Gro; Höskuldsson, Armann; Riishuus, Morten S.; Jónsdóttir, Ingibjörg; Thórdarson, Thorvaldur; Dürig, Tobias; Gudmundsson, Magnus T.; Durmont, Stephanie

2016-04-01

The Holuhraun eruption (Aug 2014- Feb 2015) is the largest effusive eruption in Iceland since the Laki eruption in 1783-84, with an estimated lava volume of ~1.6 km3 covering an area of ~83 km2. The eruption provides an unprecedented opportunity to study i) lava morphologies and their emplacement styles, ii) Morphological transitions iii) the transition from open to closed lava pathways and iv) the implication of lava pond formation. This study is based on three different categories of data; field data, airborne data and satellite data. The field data include tracking of the lava advancement by Global Positioning System (GPS) measurements and georeferenced GoPro cameras allowing classification of the lava margin morphology. Furthermore, video footage on-site documented lava emplacement. Complimentary observations have been provided from aircraft platforms and by satellite data. Of particular importance for lava morphology observations are 1-12 m/pixel airborne Synthetic Aperture Radar (SAR) images (x-band), as well as SAR data from TerraSAR-X and COSMO-SkyMed satellites. The Holuhraun lava field comprises a continuum of morphologies from pāhoehoe to 'a'ā, which have varied temporally and spatially. Shelly pāhoehoe lava was the first morphology to be observed (08-29). Spatially, this lava type was not widely distributed, but was emplaced throughout the eruption close to the vent area and the lava channels. Slabby pāhoehoe lava was initially observed the 08-31 and was observed throughout most of the eruption during the high-lava-flux phase of new lava lobe emplacement. 'A'ā lavas were the dominating morphology the first three months of the eruption and was first observed 09-01 like Rubbly pāhoehoe lava. Finally, Spiny pāhoehoe lava was first observed the 09-05 as a few marginal outbreaks along the fairly inactive parts of the 'a'ā lava lobe. However, throughout the eruption this morphology became more important and from mid-November/beginning of December the

Studies on the availability of sulphur in four soil series of soil and water management project, Patiala

International Nuclear Information System (INIS)

Sharma, Kesho Ram; Dev, G.

1974-01-01

Differential behaviour of four soils series (Banra, Fatehpur, Temple and Samana) for availability of S to wheat (Kalyan-sona) was studied in a pot experiment using five doses of labelled sulphur (0, 5, 10, 20 and 40 kg/ha) applied as (NH 4 ) 2 35 SO 4 . The yield, sulphur content and total removal of sulphur by plant, was found dependent upon sulphur supplying power of the soil, which was confirmed by the radioassay data as well. (author)

Basaltic lava flows covering active aeolian dunes in the Paraná Basin in southern Brazil: Features and emplacement aspects

Science.gov (United States)

Waichel, Breno L.; Scherer, Claiton M. S.; Frank, Heinrich T.

2008-03-01

Burial of active aeolian dunes by lava flows can preserve the morphology of the dunes and generate diverse features related to interaction between unconsolidated sediments and lavas. In the study area, located in southern Brazil, burial of aeolian deposits by Cretaceous basaltic lava flows completely preserved dunes, and generate sand-deformation features, sand diapirs and peperite-like breccia. The preserved dunes are crescentic and linear at the main contact with basalts, and smaller crescentic where interlayered with lavas. The various feature types formed on sediment surfaces by the advance of the flows reflect the emplacement style of the lavas which are compound pahoehoe type. Four feature types can be recognized: (a) type 1 features are related to the advance of sheet flows in dune-interdune areas with slopes > 5°, (b) type 2 is formed where the lava flows advance in lobes and climb the stoss slope of crescentic dunes (slopes 8-12°), (c) type 3 is generated by toes that descend the face of linear dunes (slopes 17-23°) and (d) type 4 occurs when lava lobes descend the stoss slope of crescentic dunes (slopes 10-15°). The direction of the flows, the disposition and morphology of the dunes and the ground slope are the main factors controlling formation of the features. The injection of unconsolidated sand in lava lobes forms diapirs and peperite-like breccias. Sand diapirs occur at the basal portion of lobes where the lava was more solidified. Peperite-like breccias occur in the inner portion where lava was more plastic, favoring the mingling of the components. The generation of both features is related to a mechanical process: the weight of the lava causes the injection of sand into the lava and the warming of the air in the pores of the sand facilitates this process. The lava-sediment interaction features presented here are consistent with previous reports of basalt lavas with unconsolidated arid sediments, and additional new sand-deformation features

33 CFR 117.543 - Bear Creek.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Bear Creek. 117.543 Section 117.543 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Maryland § 117.543 Bear Creek. (a) The draws of the Baltimore...

A combined study of gas geochemistry, petrology, and lava effusion at Bagana, a unique persistently active lava cone in Papua New Guinea

Science.gov (United States)

McCormick, B. T.; Salem, L. C.; Edmonds, M.; D'Aleo, R. N. M.; Aiuppa, A.; Arellano, S. R.; Wallius, J.; Galle, B.; Barry, P. H.; Ballentine, C. J.; Mulina, K.; Sindang, M.; Itikarai, I.; Wadge, G.; Lopez, T. M.; Fischer, T. P.

2016-12-01

Bagana volcano (Bougainville Island, Papua New Guinea) has exhibited nearly continuous extrusion of andesitic lava for over a century, but has largely been studied by satellite remote sensing. Satellite UV spectroscopy has revealed Bagana to be among the largest volcanic sources of sulfur dioxide worldwide. Satellite radar measurements of lava extrusion rate suggest that the entire edifice could have been built in only a few centuries. Bagana is dominantly constructed from lava flows, but also exhibits violent PDC-forming explosive eruptions, which threaten local populations.We present new multi-parameter data from fieldwork on Bagana in September 2016. UV spectrometers were deployed to ground-truth satellite observations of SO2 emissions, and track sub-daily variations in gas output. In situ measurements and sampling of emissions provide the first gas composition data for this volcano. Aerial imagery filmed by UAV was obtained to generate a high resolution DEM of the edifice for use in calibrating ongoing satellite radar studies of deformation and extrusion rate. Lava and tephra samples were gathered, with the aim of comparing melt composition and volatile content between eruptions of different style. The combination of gas geochemistry, geophysical monitoring from space, and petrology will be used to build a model framework to understand the pulsatory nature of Bagana's lava extrusion, and transitions to explosive activity.A campaign to a continuously active but poorly-studied volcano affords many opportunities for education and outreach. The campaign participants included early career scientists from five countries, who planned and carried out the fieldwork and exchanged expertise in a range of techniques. All work was undertaken in close collaboration with Rabaul Volcano Observatory, and was informed by their strategic monitoring goals, a valuable experience for the field team of synergising research activities with more operational concerns. Footage obtained

Discharging a Li-S battery with ultra-high sulphur content cathode using a redox mediator.

Science.gov (United States)

Kim, Kwi Ryong; Lee, Kug-Seung; Ahn, Chi-Yeong; Yu, Seung-Ho; Sung, Yung-Eun

2016-08-30

Lithium-sulphur batteries are under intense research due to the high specific capacity and low cost. However, several problems limit their commercialization. One of them is the insulating nature of sulphur, which necessitates a large amount of conductive agent and binder in the cathode, reducing the effective sulphur load as well as the energy density. Here we introduce a redox mediator, cobaltocene, which acts as an electron transfer agent between the conductive surface and the polysulphides in the electrolyte. We confirmed that cobaltocene could effectively convert polysulphides to Li2S using scanning electron microscope, X-ray absorption near-edge structure and in-situ X-ray diffraction studies. This redox mediator enabled excellent electrochemical performance in a cathode with ultra-high sulphur content (80 wt%). It delivered 400 mAh g(-1)cathode capacity after 50 cycles, which is equivalent to 800 mAh g(-1)S in a typical cathode with 50 wt% sulphur. Furthermore, the volumetric capacity was also dramatically improved.

Recent flood lavas in the Elysium region of Mars

International Nuclear Information System (INIS)

Plescia, J.B.

1990-01-01

A volcanic origin is presently suggested for the Cerberus Formation region of smooth plains in the southeastern Elysium region of Mars, on the basis of its surface morphology, lobate edges, vents, and an embayment relation of the unit with adjacent, older units. The low viscosity lavas that filled a topographic depression in southeastern Elysium subsequently flowed into western Amazonic Planitia via channels formed by an earlier fluvial episode. A young, upper Amazonian dating is indicated by crater frequencies and stratigraphic relations, implying that large-scale eruptions of low-viscosity lava were still possible late in Martian history. 34 refs

The fate of sulphur in the Cu-based Chemical Looping with Oxygen Uncoupling (CLOU) Process

International Nuclear Information System (INIS)

Adánez-Rubio, Iñaki; Abad, Alberto; Gayán, Pilar; García-Labiano, Francisco; Diego, Luis F. de; Adánez, Juan

2014-01-01

Highlights: • 15 h of CLOU experiments using lignite were carried out in a continuously unit. • The sulphur split between fuel- and air-reactor streams in the process was analysed. • Most of the sulphur introduced with the fuel exits as SO 2 at the fuel-reactor. • The use of a carbon separation system to reduce the S emission was evaluated. • Coals with high S content can be burnt in a CLOU process with a Cu-based material. - Abstract: The Chemical Looping with Oxygen Uncoupling (CLOU) process is a type of Chemical Looping Combustion (CLC) technology that allows the combustion of solid fuels with air, as with conventional combustion, through the use of oxygen carriers that release gaseous oxygen inside the fuel reactor. The aim of this work was to study the behaviour of the sulphur present in fuel during CLOU combustion. Experiments using lignite as fuel were carried out in a continuously operated 1.5 kW th CLOU unit during more than 15 h. Particles containing 60 wt.% CuO on MgAl 2 O 4 , prepared by spray drying, were used as the oxygen carrier in the CLOU process. The temperature in the fuel reactor varied between 900 and 935 °C. CO 2 capture, combustion efficiency and the sulphur split between fuel and air reactor streams in the process were analysed. Complete combustion of the fuel to CO 2 and H 2 O was found in all experiments. Most of the sulphur introduced with the fuel exited as SO 2 at the fuel reactor outlet, although a small amount of SO 2 was measured at the air reactor outlet. The SO 2 concentration in the air reactor exit flow decreased as the temperature in the fuel reactor increased. A carbon capture efficiency of 97.6% was achieved at 935 °C, with 87.9 wt.% of the total sulphur exiting as SO 2 in the fuel reactor. Both the reactivity and oxygen transport capacity of the oxygen carrier were unaffected during operation with a high sulphur content fuel, and agglomeration problems did not occur. Predictions were calculated regarding the use

King's Bowl Pit Crater, Lava Field and Eruptive Fissure, Idaho - A Multipurpose Volcanic Planetary Analog

Science.gov (United States)

Hughes, S. S.; Garry, B.; Kobs-Nawotniak, S. E.; Sears, D. W. G.; Borg, C.; Elphic, R. C.; Haberle, C. W.; Kobayashi, L.; Lim, D. S. S.; Sears, H.; Skok, J. R.; Heldmann, J. L.

2014-12-01

King's Bowl (KB) and its associated eruptive fissure and lava field on the eastern Snake River Plain, is being investigated by the NASA SSERVI FINESSE (Field Investigations to Enable Solar System Science and Exploration) team as a planetary analog to similar pits on the Moon, Mars and Vesta. The 2,220 ± 100 BP basaltic eruption in Craters of the Moon National Monument and Preserve represents early stages of low shield growth, which was aborted when magma supply was cut off. Compared to mature shields, KB is miniscule, with ~0.02 km3 of lava over ~3 km2, yet the ~6 km long series of fissures, cracks and pits are well-preserved for analog studies of volcanic processes. The termination of eruption was likely related to proximity of the 2,270 ± 50 BP eruption of the much larger Wapi lava field (~5.5 km3 over 325 km2 area) on the same rift. Our investigation extends early work by R. Greeley and colleagues, focusing on imagery, compositional variations, ejecta distribution, dGPS profiles and LiDAR scans of features related to: (1) fissure eruptions - spatter ramparts, cones, feeder dikes, extension cracks; (2) lava lake formation - surface morphology, squeeze-ups, slab pahoehoe lava mounds, lava drain-back, flow lobe overlaps; and (3) phreatic steam blasts - explosion pits, ejecta blankets of ash and blocks. Preliminary results indicate multiple fissure eruptions and growth of a basin-filled lava lake up to ~ 10 m thick with outflow sheet lava flows. Remnant mounds of original lake crust reveal an early high lava lake level, which subsided as much as 5 m as the molten interior drained back into the fissure system. Rapid loss of magma supply led to the collapse of fissure walls allowing groundwater influx that triggered multiple steam blasts along at least 500 m. Early blasts occurred while lake magma pressure was still high enough to produce squeeze-ups when penetrated by ejecta blocks. The King's Bowl pit crater exemplifies processes of a small, but highly energetic

Development of lava tubes in the light of observations at Mauna Ulu, Kilauea Volcano, Hawaii

Science.gov (United States)

Peterson, D.W.; Holcomb, R.T.; Tilling, R.I.; Christiansen, R.L.

1994-01-01

During the 1969-1974 Mauna Ulu eruption on Kilauea's upper east rift zone, lava tubes were observed to develop by four principal processes: (1) flat, rooted crusts grew across streams within confined channels; (2) overflows and spatter accreted to levees to build arched roofs across streams; (3) plates of solidified crust floating downstream coalesced to form a roof; and (4) pahoehoe lobes progressively extended, fed by networks of distributaries beneath a solidified crust. Still another tube-forming process operated when pahoehoe entered the ocean; large waves would abruptly chill a crust across the entire surface of a molten stream crossing through the surf zone. These littoral lava tubes formed abruptly, in contrast to subaerial tubes, which formed gradually. All tube-forming processes were favored by low to moderate volume-rates of flow for sustained periods of time. Tubes thereby became ubiquitous within the pahoehoe flows and distributed a very large proportionof the lava that was produced during this prolonged eruption. Tubes transport lava efficiently. Once formed, the roofs of tubes insulate the active streams within, allowing the lava to retain its fluidity for a longer time than if exposed directly to ambient air temperature. Thus the flows can travel greater distances and spread over wider areas. Even though supply rates during most of 1970-1974 were moderate, ranging from 1 to 5 m3/s, large tube systems conducted lava as far as the coast, 12-13 km distant, where they fed extensive pahoehoe fields on the coastal flats. Some flows entered the sea to build lava deltas and add new land to the island. The largest and most efficient tubes developed during periods of sustained extrusion, when new lava was being supplied at nearly constant rates. Tubes can play a major role in building volcanic edifices with gentle slopes because they can deliver a substantial fraction of lava erupted at low to moderate rates to sites far down the flank of a volcano. We

Comparison of the SAWNUC model with CLOUD measurements of sulphuric acid-water nucleation

CERN Document Server

Ehrhart, Sebastian; Almeida, Joao; Amorim, Antonio; Barmet, Peter; Bianchi, Federico; Dommen, Josef; Dunne, Eimear M; Duplissy, Jonathan; Franchin, Alessandro; Kangasluoma, Juha; Kirkby, Jasper; Kürten, Andreas; Kupc, Agnieszka; Lehtipalo, Katrianne; Nieminen, Tuomo; Riccobono, Francesco; Rondo, Linda; Schobesberger, Siegfried; Steiner, Gerhard; Tomé, António; Wimmer, Daniela; Baltensperger, Urs; Wagner, Paul E; Curtius, Joachim

2016-01-01

Binary nucleation of sulphuric acid-water particles is expected to be an important process in the free troposphere at low temperatures. SAWNUC (Sulphuric Acid Water Nucleation) is a model of binary nucleation that is based on laboratory measurements of the binding energies of sulphuric acid and water in charged and neutral clusters. Predictions of SAWNUC are compared for the first time comprehensively with experimental binary nucleation data from the CLOUD chamber at European Organization for Nuclear Research. The experimental measurements span a temperature range of 208–292 K, sulphuric acid concentrations from 1·106 to 1·109 cm−3, and distinguish between ion-induced and neutral nucleation. Good agreement, within a factor of 5, is found between the experimental and modeled formation rates for ion-induced nucleation at 278 K and below and for neutral nucleation at 208 and 223 K. Differences at warm temperatures are attributed to ammonia contamination which was indicated by the presence of ammonia-sulphu...

Influence of conduit flow mechanics on magma rheology and the growth style of lava domes

Science.gov (United States)

Husain, Taha; Elsworth, Derek; Voight, Barry; Mattioli, Glen; Jansma, Pamela

2018-06-01

We develop a 2-D particle-mechanics model to explore different lava-dome growth styles. These range from endogenous lava dome growth comprising expansion of a ductile dome core to the exogenous extrusion of a degassed lava plug resulting in generation of a lava spine. We couple conduit flow dynamics with surface growth of the evolving lava dome, fuelled by an open-system magma chamber undergoing continuous replenishment. The conduit flow model accounts for the variation in rheology of ascending magma that results from degassing-induced crystallization. A period of reduced effusive flow rates promote enhanced degassing-induced crystallization. A degassed lava plug extrudes exogenously for magmas with crystal contents (ϕ) of 78 per cent, yield strength >1.62 MPa, and at flow rates of 3 m3 s-1) for magma with lower relative yield strengths (p = 3 MPa) at the conduit exit is forced out by the high discharge rate pulse (2 process, which has been observed at Mount St. Helens and other locations, largely reflects gravitational loading of dome with a viscous core, with retardation by yield strength and talus friction.

33 CFR 117.841 - Smith Creek.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Smith Creek. 117.841 Section 117.841 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements North Carolina § 117.841 Smith Creek. The draw of the S117-S133...

33 CFR 117.335 - Taylor Creek.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Taylor Creek. 117.335 Section 117.335 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Florida § 117.335 Taylor Creek. The draw of US441 bridge, mile 0...

The separation of sulphur-35 and phosphorus-32 from urine and their subsequent estimation

International Nuclear Information System (INIS)

Kramer, G.H.

1981-07-01

A method has been developed that will specifically separate sulphur-35 and phosphorus-32 from urine. Interfering cations are removed by cation exchange and differential precipitation is used to remove the unwanted anion(s). The anion of interest is estimated by liquid scintillation counting and recoveries are 95% for sulphur-35 and 70% for phosphorus-32. The detection limits for sulphur-35 and phosphorus-32 are estimated to be 1.5 pCi and 1.3 pCi, respectively (1 pCi = 37 mBq)

Sulphur-oxidizing and sulphate-reducing communities in Brazilian mangrove sediments.

Science.gov (United States)

Varon-Lopez, Maryeimy; Dias, Armando Cavalcante Franco; Fasanella, Cristiane Cipolla; Durrer, Ademir; Melo, Itamar Soares; Kuramae, Eiko Eurya; Andreote, Fernando Dini

2014-03-01

Mangrove soils are anaerobic environments rich in sulphate and organic matter. Although the sulphur cycle is one of the major actors in this ecosystem, little is known regarding the sulphur bacteria communities in mangrove soils. We investigated the abundance, composition and diversity of sulphur-oxidizing (SOB) and sulphate-reducing (SRB) bacteria in sediments from three Brazilian mangrove communities: two contaminated, one with oil (OilMgv) and one with urban waste and sludge (AntMgv), and one pristine (PrsMgv). The community structures were assessed using quantitative real-time polymerase chain reaction (qPCR), polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and clone libraries, using genes for the enzymes adenosine-5'-phosphosulphate reductase (aprA) and sulphite reductase (Dsr) (dsrB). The abundance for qPCR showed the ratio dsrB/aprA to be variable among mangroves and higher according to the gradient observed for oil contamination in the OilMgv. The PCR-DGGE patterns analysed by Nonmetric Multidimensional Scaling revealed differences among the structures of the three mangrove communities. The clone libraries showed that Betaproteobacteria, Gammaproteobacteria and Deltaproteobacteria were the most abundant groups associated with sulphur cycling in mangrove sediments. We conclude that the microbial SOB and SRB communities in mangrove soils are different in each mangrove forest and that such microbial communities could possibly be used as a proxy for contamination in mangrove forests. © 2013 John Wiley & Sons Ltd and Society for Applied Microbiology.

CREEK Project's Phytoplankton Pigment Monitoring Database for Eight Creeks in the North Inlet Estuary, South Carolina: 1997-1999

Data.gov (United States)

Baruch Institute for Marine and Coastal Sciences, Univ of South Carolina — The CREEK Project began in January of 1996 and was designed to help determine the role of oysters, Crassostrea virginica, in tidal creeks of the North Inlet Estuary,...

Bridge Creek IMW database - Bridge Creek Restoration and Monitoring Project

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The incised and degraded habitat of Bridge Creek is thought to be limiting a population of ESA-listed steelhead (Oncorhynchus mykiss). A logical restoration approach...

Diagnostic value of the fluoroscopic triggering 3D LAVA technique for primary liver cancer.

Science.gov (United States)

Shen, Xiao-Yong; Chai, Chun-Hua; Xiao, Wen-Bo; Wang, Qi-Dong

2010-04-01

Primary liver cancer (PLC) is one of the common malignant tumors. Liver acquisition with acceleration volume acquisition (LAVA), which allows simultaneous dynamic enhancement of the hepatic parenchyma and vasculature imaging, is of great help in the diagnosis of PLC. This study aimed to evaluate application of the fluoroscopic triggering 3D LAVA technique in the imaging of PLC and liver vasculature. The clinical data and imaging findings of 38 adults with PLC (22 men and 16 women; average age 52 years), pathologically confirmed by surgical resection or biopsy, were collected and analyzed. All magnetic resonance images were obtained with a 1.5-T system (General Electrics Medical Systems) with an eight-element body array coil and application of the fluoroscopic triggering 3D LAVA technique. Overall image quality was assessed on a 5-point scale by two experienced radiologists. All the nodules and blood vessel were recorded and compared. The diagnostic accuracy and feasibility of LAVA were evaluated. Thirty-eight patients gave high quality images of 72 nodules in the liver for diagnosis. The accuracy of LAVA was 97.2% (70/72), and the coincidence rate between the extent of tumor judged by dynamic enhancement and pathological examination was 87.5% (63/72). Displayed by the maximum intensity projection reconstruction, nearly all cases gave satisfactory images of branches III and IV of the hepatic artery. Furthermore, small early-stage enhancing hepatic lesions and the parallel portal vein were also well displayed. Sequence of LAVA provides good multi-phase dynamic enhancement scanning of hepatic lesions. Combined with conventional scanning technology, LAVA effectively and safely displays focal hepatic lesions and the relationship between tumor and normal tissues, especially blood vessels.

Asotin Creek Model Watershed Plan

Energy Technology Data Exchange (ETDEWEB)

Browne, D.; Holzmiller, J.; Koch, F.; Polumsky, S.; Schlee, D.; Thiessen, G.; Johnson, C.

1995-04-01

The Asotin Creek Model Watershed Plan is the first to be developed in Washington State which is specifically concerned with habitat protection and restoration for salmon and trout. The plan is consistent with the habitat element of the ``Strategy for Salmon``. Asotin Creek is similar in many ways to other salmon-bearing streams in the Snake River system. Its watershed has been significantly impacted by human activities and catastrophic natural events, such as floods and droughts. It supports only remnant salmon and trout populations compared to earlier years. It will require protection and restoration of its fish habitat and riparian corridor in order to increase its salmonid productivity. The watershed coordinator for the Asotin County Conservation District led a locally based process that combined local concerns and knowledge with technology from several agencies to produce the Asotin Creek Model Watershed Plan.

Blowing off steam: Tuffisite formation as a regulator for lava dome eruptions

Directory of Open Access Journals (Sweden)

Jackie Evan Kendrick

2016-04-01

Full Text Available Tuffisites are veins of variably sintered, pyroclastic particles that form in conduits and lava domes as a result of localized fragmentation events during gas-and-ash explosions. Those observed in-situ on the active 2012 lava dome of Volcán de Colima range from voids with intra-clasts showing little movement and interpreted to be failure-nuclei, to sub-parallel lenses of sintered granular aggregate interpreted as fragmentation horizons, through to infilled fractures with evidence of viscous remobilization. All tuffisites show evidence of sintering. Further examination of the complex fracture-and-channel patterns reveals viscous backfill by surrounding magma, suggesting that lava fragmentation was followed by stress relaxation and continued viscous deformation as the tuffisites formed. The natural tuffisites are more permeable than the host andesite, and have a wide range of porosity and permeability compared to a narrower window for the host rock, and gauging from their significant distribution across the dome, we posit that the tuffisite veins may act as important outgassing pathways. To investigate tuffisite formation we crushed and sieved andesite from the lava dome and sintered it at magmatic temperatures for different times. We then assessed the healing and sealing ability by measuring porosity and permeability, showing that sintering reduces both over time. During sintering the porosity-permeability reduction occurs due to the formation of viscous necks between adjacent grains, a process described by the neck-formation model of Frenkel (1945. This process leads the granular starting material to a porosity-permeability regime anticipated for effusive lavas, and which describes the natural host lava as well as the most impervious of natural tuffisites. This suggests that tuffisite formation at Volcán de Colima constructed a permeable network that enabled gas to bleed passively from the magma. We postulate that this progressively reduced

Rubber composites cured with sulphur and peroxide and ...

Indian Academy of Sciences (India)

Besides classical applications of rubber products in tyres, ... application of sulphur curing systems leads to the forming ..... mobile sulphidic cross-links which promote crystallization of NR. ... PhD Thesis (Kingston, Ontario: Queen's University).

The implications of the new sulphur limits on the European Ro-Ro sector

DEFF Research Database (Denmark)

Zis, Thalis; Psaraftis, Harilaos N.

2017-01-01

In an effort to reduce the environmental impacts of maritime transportation, the International Maritime Organization (IMO) designated special Sulphur Emission Control Areas (SECAs) where ships are required to use low-sulphur fuel. In January 2015, the sulphur limit within SECAs was lowered to 0...... and the redistribution of transport. Recommendations to mitigate and reverse the negative side-effects of such environmental legislation are proposed....... analyses on market share data, cargo values, freight rates, and haulers rates are conducted. Emissions inventories are constructed to assess the environmental efficacy of the SECA regulation. The novelty of the proposed model lies in the examination of the ex-post implications of shutting down a service...

A Sinuous Tumulus over an Active Lava Tube at Klauea Volcano: Evolution, Analogs, and Hazard Forecasts

Science.gov (United States)

Orr, Tim R.; Bleacher, Jacob E.; Patrick, Matthew R.; Wooten, Kelly M.

2015-01-01

Inflation of narrow tube-fed basaltic lava flows (tens of meters across), such as those confined by topography, can be focused predominantly along the roof of a lava tube. This can lead to the development of an unusually long tumulus, its shape matching the sinuosity of the underlying lava tube. Such a situation occurred during Klauea Volcanos (Hawaii, USA) ongoing East Rift Zone eruption on a lava tube active from July through November 2010. Short-lived breakouts from the tube buried the flanks of the sinuous, ridge-like tumulus, while the tumulus crest, its surface composed of lava formed very early in the flows emplacement history, remained poised above the surrounding younger flows. At least several of these breakouts resulted in irrecoverable uplift of the tube roof. Confined sections of the prehistoric Carrizozo and McCartys flows (New Mexico, USA) display similar sinuous, ridge-like features with comparable surface age relationships. We contend that these distinct features formed in a fashion equivalent to that of the sinuous tumulus that formed at Kilauea in 2010. Moreover, these sinuous tumuli may be analogs for some sinuous ridges evident in orbital images of the Tharsis volcanic province on Mars. The short-lived breakouts from the sinuous tumulus at Kilauea were caused by surges in discharge through the lava tube, in response to cycles of deflation and inflation (DI events) at Kilauea's summit. The correlation between DI events and subsequent breakouts aided in lava flow forecasting. Breakouts from the sinuous tumulus advanced repeatedly toward the sparsely populated Kalapana Gardens subdivision, destroying two homes and threatening others. Hazard assessments, including flow occurrence and advance forecasts, were relayed regularly to the Hawai?i County Civil Defense to aid their lava flow hazard mitigation efforts while this lava tube was active.

Effects of potential surface coal mining on dissolved solids in Otter Creek and in the Otter Creek alluvial aquifer, southeastern Montana

Science.gov (United States)

Cannon, M.R.

1985-01-01

Otter Creek drains an area of 709 square miles in the coal-rich Powder River structural basin of southeastern Montana. The Knobloch coal beds in the Tongue River Member of the Paleocene Fort Union Formation is a shallow aquifer and a target for future surface mining in the downstream part of the Otter Creek basin. A mass-balance model was used to estimate the effects of potential mining on the dissolved solids concentration in Otter Creek and in the alluvial aquifer in the Otter Creek valley. With extensive mining of the Knobloch coal beds, the annual load of dissolved solids to Otter Creek at Ashland at median streamflow could increase by 2,873 tons, or a 32-percent increase compared to the annual pre-mining load. Increased monthly loads of Otter Creek, at the median streamflow, could range from 15 percent in February to 208 percent in August. The post-mining dissolved solids load to the subirrigated part of the alluvial valley could increase by 71 percent. The median dissolved solids concentration in the subirrigated part of the valley could be 4,430 milligrams per liter, compared to the pre-mining median concentration of 2,590 milligrams per liter. Post-mining loads from the potentially mined landscape were calculated using saturated-paste-extract data from 506 overburdened samples collected from 26 wells and test holes. Post-mining loads to the Otter Creek valley likely would continue at increased rates for hundreds of years after mining. If the actual area of Knobloch coal disturbed by mining were less than that used in the model, post-mining loads to the Otter Creek valley would be proportionally smaller. (USGS)

Sources of baseflow for the Minnehaha Creek Watershed, Minnesota, US

Science.gov (United States)

Nieber, J. L.; Moore, T. L.; Gulliver, J. S.; Magner, J. A.; Lahti, L. B.

2013-12-01

Minnehaha Creek is among the most valued surface water features in the Minneapolis, MN metro area, with a waterfall as it enters the Minnehaha Creek park. Flow in Minnehaha Creek is heavily dependent on discharge from the stream's origin, Lake Minnetonka, the outlet of which is closed during drought periods to maintain water elevations in the lake resulting in low- (or no-) flow conditions in the creek. Stormwater runoff entering directly to the creek from the creek's largely urbanized watershed exacerbates extremes in flow conditions. Given the cultural and ecological value of this stream system, there is great interest in enhancing the cultural and ecosystem services provided by Minnehaha Creek through improvements in streamflow regime by reducing flashiness and sustaining increased low-flows. Determining the potential for achieving improvements in flow requires first that the current sources of water contributing to low-flows in the creek be identified and quantified. Work on this source identification has involved a number of different approaches, including analyses of the streamflow record using a hydrologic system model framework, examination of the Quaternary and bedrock geology of the region, estimation of groundwater-surface water exchange rates within the channel using hyporheic zone temperature surveys and flux meter measurements, and analyses of the stable isotopes of oxygen and hydrogen in samples of stream water, groundwater, and rainfall. Analysis of baseflow recessions using the method of Brutsaert and Nieber (1977) indicates that only a small portion of the catchment, probably the riparian zone, contributes to baseflows. This result appears to be supported by the observation that the limestone/shale bedrock layer underlying the surficial aquifer has a non-zero permeability, and in a significant portion of the watershed the layer has been eroded away leaving the surficial aquifer ';bottomless' and highly susceptible to vertical (down) water loss

The mechanism of photosystem-II inactivation during sulphur deprivation-induced H2 production in Chlamydomonas reinhardtii.

Science.gov (United States)

Nagy, Valéria; Vidal-Meireles, André; Podmaniczki, Anna; Szentmihályi, Klára; Rákhely, Gábor; Zsigmond, Laura; Kovács, László; Tóth, Szilvia Z

2018-05-01

Sulphur limitation may restrain cell growth and viability. In the green alga Chlamydomonas reinhardtii, sulphur limitation may induce H 2 production lasting for several days, which can be exploited as a renewable energy source. Sulphur limitation causes a large number of physiological changes, including the inactivation of photosystem II (PSII), leading to the establishment of hypoxia, essential for the increase in hydrogenase expression and activity. The inactivation of PSII has long been assumed to be caused by the sulphur-limited turnover of its reaction center protein PsbA. Here we reinvestigated this issue in detail and show that: (i) upon transferring Chlamydomonas cells to sulphur-free media, the cellular sulphur content decreases only by about 25%; (ii) as demonstrated by lincomycin treatments, PsbA has a significant turnover, and other photosynthetic subunits, namely RbcL and CP43, are degraded more rapidly than PsbA. On the other hand, sulphur limitation imposes oxidative stress early on, most probably involving the formation of singlet oxygen in PSII, which leads to an increase in the expression of GDP-L-galactose phosphorylase, playing an essential role in ascorbate biosynthesis. When accumulated to the millimolar concentration range, ascorbate may inactivate the oxygen-evolving complex and provide electrons to PSII, albeit at a low rate. In the absence of a functional donor side and sufficient electron transport, PSII reaction centers are inactivated and degraded. We therefore demonstrate that the inactivation of PSII is a complex and multistep process, which may serve to mitigate the damaging effects of sulphur limitation. © 2018 The Authors The Plant Journal © 2018 John Wiley & Sons Ltd.

Accidental sulphuric acid poisoning in a newborn | Abdulkadir ...

African Journals Online (AJOL)

Accidental sulphuric acid poisoning in a newborn. I Abdulkadir, L Hassan, F Abdullahi, FD Akeredolu, S Purdue, M Okpe, AM Sobowale, OA Adewumi, U Abdullahi, MA Onadiran, TT Sholadoye, S Baba, WN Ogala ...

Calculated viscosity-distance dependence for some actively flowing lavas

International Nuclear Information System (INIS)

Pieri, D.

1987-01-01

The importance of viscosity as a gauge of the various energy and momentum dissipation regimes of lava flows has been realized for a long time. Nevertheless, despite its central role in lava dynamics and kinematics, it remains among the most difficult of flow physical properties to measure in situ during an eruption. Attempts at reconstructing the actual emplacement viscosities of lava flows from their solidified topographic form are difficult. Where data are available on the position of an advancing flow front as a function of time, it is possible to calculate the effective viscosity of the front as a function of distance from the vent, under the assumptions of a steady state regime. As an application and test of an equation given, relevant parameters from five recent flows on Mauna Loa and Kilauea were utilized to infer the dynamic structure of their aggregate flow front viscosity as they advanced, up to cessation. The observed form of the viscosity-distance relation for the five active Hawaiian flows examined appears to be exponential, with a rapid increase just before the flows stopped as one would expect

The non-participation of organic sulphur in acid mine drainage generation.

Science.gov (United States)

Casagrande, D J; Finkelman, R B; Caruccio, F T

1989-12-01

Acid mine drainage is commonly associated with land disturbances that encounter and expose iron sulphides to oxidising atmospheric conditions. The attendant acidic conditions solubilise a host of trace metals. Within this flow regime the potential exists to contaminate surface drinking water supplies with a variety of trace materials. Accordingly, in evaluating the applications for mines located in the headwaters of water sheds, the pre-mining prediction of the occurrence of acid mine drainage is of paramount importance.There is general agreement among investigators that coal organic sulphur is a nonparticipant in acid mine drainage generation; however, there is no scientific documentation to support this concensus. Using simulated weathering, kinetic, mass balance, petrographic analysis and a peroxide oxidation procedure, coal organic sulphur is shown to be a nonparticipant in acid mine drainage generation. Calculations for assessing the acid-generating potential of a sedimentary rock should not include organic sulphur content.

Trends in atmospheric deposition fluxes of sulphur and nitrogen in Czech forests

International Nuclear Information System (INIS)

Hůnová, Iva; Maznová, Jana; Kurfürst, Pavel

2014-01-01

We present the temporal trends and spatial changes of deposition of sulphur and nitrogen in Czech forests based on records from long-term monitoring. A statistically significant trend for sulphur was detected at most of the sites measuring for wet, dry, and total deposition fluxes and at many of these the trend was also present for the period after 2000. The spatial pattern of the changes in sulphur deposition flux between 1995 and 2011 shows the decrease over the entire forested area in a wide range of 18.1–0.2 g m −2 year −1 with the most pronounced improvement in formerly most impacted regions. Nitrogen still represents a considerable stress in many areas. The value of nitrogen deposition flux of 1 g m −2 year −1 is exceeded over a significant portion of the country. On an equivalent basis, the ion ratios of NO 3 − /SO 4 2− and NH 4 + /SO 4 2− in precipitation show significantly increasing trends in time similarly to those of pH. -- Highlights: • Significant decrease of sulphur deposition at most of sites has been recorded. • Nitrogen deposition still represents a considerable stress in Czech forests. • Significantly increasing trends of NO 3 − /SO 4 2− , NH 4 + /SO 4 2− , and pH in precipitation. -- While sulphur deposition significantly decreased with the highest improvement in formerly most affected areas, nitrogen deposition still represents a considerable stress in Czech forests

Constraining Controls on the Emplacement of Long Lava Flows on Earth and Mars Through Modeling in ArcGIS

Science.gov (United States)

Golder, K.; Burr, D. M.; Tran, L.

2017-12-01

Regional volcanic processes shaped many planetary surfaces in the Solar System, often through the emplacement of long, voluminous lava flows. Terrestrial examples of this type of lava flow have been used as analogues for extensive martian flows, including those within the circum-Cerberus outflow channels. This analogy is based on similarities in morphology, extent, and inferred eruptive style between terrestrial and martian flows, which raises the question of how these lava flows appear comparable in size and morphology on different planets. The parameters that influence the areal extent of silicate lavas during emplacement may be categorized as either inherent or external to the lava. The inherent parameters include the lava yield strength, density, composition, water content, crystallinity, exsolved gas content, pressure, and temperature. Each inherent parameter affects the overall viscosity of the lava, and for this work can be considered a subset of the viscosity parameter. External parameters include the effusion rate, total erupted volume, regional slope, and gravity. To investigate which parameter(s) may control(s) the development of long lava flows on Mars, we are applying a computational numerical-modelling to reproduce the observed lava flow morphologies. Using a matrix of boundary conditions in the model enables us to investigate the possible range of emplacement conditions that can yield the observed morphologies. We have constructed the basic model framework in Model Builder within ArcMap, including all governing equations and parameters that we seek to test, and initial implementation and calibration has been performed. The base model is currently capable of generating a lava flow that propagates along a pathway governed by the local topography. At AGU, the results of model calibration using the Eldgá and Laki lava flows in Iceland will be presented, along with the application of the model to lava flows within the Cerberus plains on Mars. We then

Effects of phosphorus and sulphur on dry matter yield of maize ( Zea ...

African Journals Online (AJOL)

A screen-house experiment was conducted to investigate the effects of phosphorus (P) and sulphur (S) on maize dry-matter yield (MDY) in soils of five locations (Obantoko I, II, Alabata I, II, and III) in Abeokuta, Ogun State of Nigeria. Three levels of sulphur (0, 10 and 20 kg S ha–1) and phosphorus (0, 30 and 45 kg P ha–1) ...

27 CFR 9.211 - Swan Creek.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Swan Creek. 9.211 Section 9.211 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.211 Swan Creek. (a) Name. The name of the viticultural are...

Monitoring the cooling of the 1959 Kīlauea Iki lava lake using surface magnetic measurements

Science.gov (United States)

Gailler, Lydie; Kauahikaua, James P.

2017-01-01

Lava lakes can be considered as proxies for small magma chambers, offering a unique opportunity to investigate magma evolution and solidification. Repeated magnetic ground surveys over more than 50 years each show a large vertical magnetic intensity anomaly associated with Kīlauea Iki Crater, partly filled with a lava lake during the 1959 eruption of Kīlauea Volcano (Island of Hawai’i). The magnetic field values recorded across the Kīlauea Iki crater floor and the cooling lava lake below result from three simple effects: the static remnant magnetization of the rocks forming the steep crater walls, the solidifying lava lake crust, and the hot, but shrinking, paramagnetic non-magnetic lens (>540 °C). We calculate 2D magnetic models to reconstruct the temporal evolution of the geometry of this non-magnetic body, its depth below the surface, and its thickness. Our results are in good agreement with the theoretical increase in thickness of the solidifying crust with time. Using the 2D magnetic models and the theoretical curve for crustal growth over a lava lake, we estimate that the former lava lake will be totally cooled below the Curie temperature in about 20 years. This study shows the potential of magnetic methods for detecting and monitoring magmatic intrusions at various scales.

Currents and siltation at Dharamtar creek, Bombay

Digital Repository Service at National Institute of Oceanography (India)

Swamy, G.N.; Kolhatkar, V.M.; Fernandes, A.A.

Hydrographic data collected in Dharamtar Creek during 1976-77 have been analysed. This showed that the waters in the Creek are well mixed and the salinity varied with the tide. The tidal currents are found to be generally strong. The distribution...

Degassing during magma ascent in the Mule Creek vent (USA)

Science.gov (United States)

Stasiuk, M.V.; Barclay, J.; Carroll, M.R.; Jaupart, Claude; Ratte, J.C.; Sparks, R.S.J.; Tait, S.R.

1996-01-01

The structures and textures of the rhyolite in the Mule Creek vent (New Mexico, USA) indicate mechanisms by which volatiles escape from silicic magma during eruption. The vent outcrop is a 300-m-high canyon wall comprising a section through the top of a feeder conduit, vent and the base of an extrusive lava dome. Field relations show that eruption began with an explosive phase and ended with lava extrusion. Analyses of glass inclusions in quartz phenocrysts from the lava indicate that the magma had a pre-eruptive dissolved water content of 2.5-3.0 wt% and, during eruption, the magma would have been water-saturated over the vertical extent of the present outcrop. However, the vesicularity of the rhyolite is substantially lower than that predicted from closed-system models of vesiculation under equilibrium conditions. At a given elevation in the vent, the volume fraction of primary vesicles in the rhyolite increases from zero close to the vent margin to values of 20-40 vol.% in the central part. In the centre the vesicularity increases upward from approximately 20 vol.% at 300 m below the canyon rim to approximately 40 vol.% at 200 m, above which it shows little increase. To account for the discrepancy between observed vesicularity and measured water content, we conclude that gas escaped during ascent, probably beginning at depths greater than exposed, by flow through the vesicular magma. Gas escape was most efficient near the vent margin, and we postulate that this is due both to the slow ascent of magma there, giving the most time for gas to escape, and to shear, favouring bubble coalescence. Such shear-related permeability in erupting magma is supported by the preserved distribution of textures and vesicularity in the rhyolite: Vesicles are flattened and overlapping near the dense margins and become progressively more isolated and less deformed toward the porous centre. Local zones have textures which suggest the coalescence of bubbles to form permeable

Abatements of reduced sulphur compounds, colour, and organic matter from indigo dyeing effluents by electrocoagulation.

Science.gov (United States)

Tünay, Olcay; Simşeker, Merve; Kabdaşli, Isik; Olmez-Hanci, Tugba

2014-08-01

In the present study, the treatability of indigo dyeing effluents by the electrocoagulation (EC) process using stainless steel electrodes was experimentally investigated. The samples used were concentrated with main pollutant parameters of chemical oxygen demand (COD) (1000-1100 mg/L), reduced sulphur species (over 2000 mg SO2-(3)/L), and colour (0.12-0.13 1/cm). The study focused on the effect of main operation parameters on the EC process performance in terms of abatement of reduced sulphur compounds as well as decolourization and organic matter reduction. Results indicated that the performance of EC proved to be high providing total oxidation of the reduced sulphur compounds, almost complete decolourization, and COD removal up to 90%. Increasing applied current density from 22.5 to 45 mA/cm2 appreciably improved abatement of the reduced sulphur compounds for Sample I, but a further increase in the applied current density to 67.5 mA/cm2 did not accelerate the conversion rate to sulphate. The process performance was adversely affected by increasing initial concentration of the reduced sulphur compounds. Decolourization and organic matter removal efficiency enhanced with increasing applied current density. The main removal mechanism of the reduced sulphur compounds by EC was explained as conversion to sulphate via oxidation. Conversion rate to sulphate fitted pseudo-first-order kinetics very well.

Design and modeling of an advanced marine machinery system including waste heat recovery and removal of sulphur oxides

DEFF Research Database (Denmark)

Frimann Nielsen, Rasmus; Haglind, Fredrik; Larsen, Ulrik

2014-01-01

the efficiency of machinery systems. The wet sulphuric acid process is an effective way of removing flue gas sulphur oxides from land-based coal-fired power plants. Moreover, organic Rankine cycles (ORC) are suitable for heat to power conversion for low temperature heat sources. This paper describes the design...... that an ORC placed after the conventional waste heat recovery system is able to extract the sulphuric acid from the exhaust gas, while at the same time increase the combined cycle thermal efficiency by 2.6%. The findings indicate that the technology has potential in marine applications regarding both energy...... and modeling of a highly efficient machinery system which includes the removal of exhaust gas sulphur oxides. The system consists of a two-stroke diesel engine, the wet sulphuric process for sulphur removal, a conventional steam Rankine cycle and an ORC. Results of numerical modeling efforts suggest...

Modeling mechanical and thermo-mechanical erosion by flowing lava at Raglan, Cape Smith Belt, New Québec, Canada

Science.gov (United States)

Cataldo, V.; Williams, D. A.; Lesher, C. M.

2015-12-01

The 1.5-D Williams et al. model of thermal erosion by turbulent lava was recently applied to the Athabasca Valles lava channel on Mars, in an attempt to establish the importance of thermal erosion in excavating this ~80-100 m deep outflow channel. The modeled erosion depths (0.4-7.5 m) are far less than the depth of the channel which, combined with the short duration of the eruption, suggests that mechanical erosion may have had a greater role. Several studies suggest that mechanical erosion by lava is more important in channel-tube formation than previously thought, under certain circumstances. How would we be able to distinguish between mechanical and thermal erosion? By investigating model results when substrate properties change, as we move from a consolidated, mechanically strong substrate to a partially consolidated or unconsolidated, mechanically weaker substrate. The Proterozoic Raglan komatiitic basalt lava channel of the Cape Smith Belt, New Québec, Canada is a complex erosional environment involving invasive erosion of both sediment and gabbro substrates - which makes it a critical test case. The lava eroded an upper layer of soft sediment, with erosion at the tops, bottoms, and sides of the conduit, through underlying gabbro, and then burrowed laterally into underlying sediment, a scenario requiring a two-dimensional modeling approach. Using the available field data, we will simulate two-dimensional thermomechanical and mechanical erosion interfaces on all sides of a turbulent lava flow by creating a finite-element mesh. The mesh will be defined by the geometry of the lava flow at those lava conduits for which data on lava and substrate composition, lava thickness, slope of the ground, conduit area and volume, and lava flow length are available. Ultimately, this model will be applied to lunar sinuous rilles and martian lava channels for which the use of a two-dimensional approach is needed.

Fate of gypsum-sulphur applied to soybean on Typic haplustepts

International Nuclear Information System (INIS)

Saharan, Neelam; Rattan, R.K.

2004-01-01

Field experiments were conducted on the sulphur-deficient Typic Haplustepts of the IARI farm for two consecutive, kharif seasons viz. 1996 and 1997 with soybean cultivar Pusa 22 as the crop. Varying rates of S as gypsum were basally applied in the main plots adjacent to the micro plots (1 m x 1 m) to quantify the partitioning of the fertilizer-sulphur taken up by soybean and its distribution in the soil profile. Soybean responded to the application of sulphur, with increase in yield being obtained up to rate of 40 kg S ha -1 . Data computed on distribution of the S derived from labelled gypsum and percent S utilization by the soybean crop increased from 13.23 and 4.15 to 23.41 and 6.39, respectively. During 1996, the per cent utilization of labelled S ranged from 5.6 to 8.8. Monitoring of added sulphur in the soil profile up to a depth of 1 m revealed maximum accumulation of the added S in 30-60 cm soil layer. With the help of 35 S around 11 to 18 per cent of the added S was traced in 60-100 cm soil layer. It can be concluded from the data for two years that during kharif season the application of S through water soluble sources like ammonium sulphate and ammonium phosphate sulphate should be avoided because even S from the sparingly soluble gypsum migrated to a depth of 1 m during the cropping season. (author)

NA35: sulphur-gold collision

CERN Multimedia

1991-01-01

In this image the real particles produced by the collision of a 6400 GeV sulphur ion with a gold target can be seen as they pass through a streamer chamber. Streamer chambers consist of a gas chamber through which a strong pulsed electric field is passed, creating sparks as a charged particle passes through it. The NA35 experiment, which was in operation in the 1980s, was part of CERN's ongoing heavy ion project.

Soil and applied sulphur utilization by sunflower grown on vertisol under rainfed conditions

International Nuclear Information System (INIS)

Sreemannarayana, B.; Sreenivasa Raju, A.

1993-01-01

In a field experiment, conducted with sunflower genotypes viz., Morden, APSH-11, and EC 68414 grown on a local black clay loam soil, fertilizer sulphur (labelled with 35 S) was applied at the rate of 0, 20, 40 and 60 kg S/ha through gypsum and ammonium sulphate. Among the sunflower genotypes, EC 68414 utilized maximum sulphur from the sources at any given growth stage i.e., star, bud, flowering and maturity. Sulphur applied through ammonium sulphate resulted in highest S utilization by all the genotypes at all the stages of growth. Though, sulphur uptake showed an increase, the S utilization decreased with increase in levels of S. The S uptake was highest at 60 kg S/ha level applied through any of the sources. The soil S uptake was higher than fertilizer S uptake at any given stage of crop. Maximum yields were recorded at 40 kg S/ha level signifying that this dose is optimum for sunflower grown on black clay loam soils. (author). 17 refs., 3 tabs

Development of a Temperature Programmed Identification Technique to Characterize the Organic Sulphur Functional Groups in Coal

Directory of Open Access Journals (Sweden)

Moinuddin Ghauri

2017-06-01

Full Text Available The Temperature Programmed Reduction (TPR technique is employed for the characterisation of various organic sulphur functional groups in coal. The TPR technique is modified into the Temperature Programmed Identification technique to investigate whether this method can detect various functional groups corresponding to their reduction temperatures. Ollerton, Harworth, Silverdale, Prince of Wales coal and Mequinenza lignite were chosen for this study. High pressure oxydesulphurisation of the coal samples was also done. The characterization of various organic sulphur functional groups present in untreated and treated coal by the TPR method and later by the TPI method confirmed that these methods can identify the organic sulphur groups in coal and that the results based on total sulphur are comparable with those provided by standard analytical techniques. The analysis of the untreated and treated coal samples showed that the structural changes in the organic sulphur matrix due to a reaction can be determined.

Total mineral material, acidity, sulphur, and nitrogen in rain and snow at Kentville, Nova Scotia

Energy Technology Data Exchange (ETDEWEB)

Herman, F A; Gorham, E

1957-01-01

Analyses of total ash, sulphur, ph, ammonia, and nitrate nitrogen have been made on 23 monthly precipitation samples and 17 individual snow samples collected between June 1952 and May 1954 at Kentville, Nova Scotia, in a predominantly agricultural area. Mean annual supply of total mineral ash was 95 kg/ha, of sulphur 9.1 hg/ha, of ammonia nitrogen 2.8 kg/ha, and of nitrate nitrogen 1.1 kg/ha. Average pH was 5.7, and rains more acid than this exhibited higher levels of both nitrate and sulphur, and a marked correlation between the latter and ammonia. Snow samples had much lower concentrations of ash, sulphur, and nitrogen than rain samples collected in the same months, which may perhaps indicate a lower efficiency of snow flakes in removing materials from the atmosphere.

Sulphur Nutrition and its Effect on Yield and Oil Content of Oilseed Rape (Brassica Napus L.

Directory of Open Access Journals (Sweden)

Mária Varényiová

2017-01-01

Full Text Available The aim of the experiment was to study the importance of sulphur in oilseed rape (Brassica napus L. nutrition as well as the effect of rising doses of sulphur in combination with nitrogen on yield, oiliness, oil production, nutrients content in seed and nutrients uptake by rapeseed. The plot–scale experiment was established in years 2013/14 and 2014/15 within the agricultural cooperative in Mojmírovce. There were four fertilization treatments on 600 m2 experimental plots in three replications in this experiment. The first treatment was unfertilized control. Other three treatments were fertilized by the same nitrogen dose of 160 kg.ha−1 and by increasing doses of sulphur. The second treatment was fertilized by a dose of 15 kg.ha−1 S, the third by a dose of 40 kg.ha−1 and a dose of 65 kg.ha−1 S was applied at the fourth treatment. The highest average yield 3.96 t.ha-1 was found when a dose of 40 kg.ha−1 S was applied. The application of sulphur in a dose of 65 kg.ha−1 was accompanied by a yield decrease by 11.4 % as compared to the treatment where a sulphur dose of 40 kg.ha−1 was used. An average oil content of 45.1, 45.5, and 44.0 % was found in treatments in which the doses of sulphur of 15, 40 and 65 kg.ha−1 were applied. No significant difference among the treatments fertilized by sulphur was found. The average oil production reached 1809, 1802 and 1595 kg.ha−1 in cases of treatments fertilized by sulphur doses of 15, 40 and 65 kg.ha−1.

Analytical protocols for characterisation of sulphur-free lignin

NARCIS (Netherlands)

Gosselink, R.J.A.; Abächerli, A.; Semke, H.; Malherbe, R.; Käuper, P.; Nadif, A.; Dam, van J.E.G.

2004-01-01

Interlaboratory tests for chemical characterisation of sulphur-free lignins were performed by five laboratories to develop useful analytical protocols, which are lacking, and identify quality-related properties. Protocols have been established for reproducible determination of the chemical

A compact XRF unit for determining total sulphur content in coals

International Nuclear Information System (INIS)

Sumitra, T.; Chankow, N.; Punnachaiya, S.; Srisatit, S.

1994-01-01

A microcomputer based x-ray fluorescence (XRF) unit was developed for off-line determination of total sulphur content in coal samples. The unit consisted of the x-ray exciting/measuring set and the microcomputer with a plug-in interface card. An Fe-55 radioisotope was used as the exciting source while a krypton-filled proportional counter was used to measure x-rays from the samples. The x-ray spectrum was simultaneously displayed on the microcomputer screen. For quantitative determination of sulphur, the intensities of sulphur K x-rays as well as calcium K x-rays and scattered x-rays were taken into account. The unit was tested with finely-ground, dried and compressed lignite, subbituminous and bituminous samples. If was found that for low-calcium coals, the results were in good agreement with those obtained from the standard chemical analysis method within ± 0.2% and within ± 0.5%S for high-calcium coals. 2 refs., 2 tabs., 3 figs

CREEK Project's Internal Creek Habitat Survey for Eight Creeks in the North Inlet Estuary, South Carolina: January 1998.

Data.gov (United States)

Baruch Institute for Marine and Coastal Sciences, Univ of South Carolina — A group of eight intertidal creeks with high densities of oysters, Crassostrea virginica, in North Inlet Estuary, South Carolina, USA were studied using a replicated...

Analysis of sulphur, phosphorus and silica in metals, alloys, inorganic compounds and solvents

International Nuclear Information System (INIS)

Upadhya, J.C.; Naik, S.S.; Khedikar, W.K.; Sudersanan, M.; Mathur, P.K

1999-10-01

Procedures for the analysis of sulphur, phosphorus and silica in various metals and alloys like mild steel, carbon steel and stainless steel as well as nickel base alloys are described. Procedures were also developed for the analysis of sulphur in thoria pellets and in other materials like crack check fluids, coal etc. Typical results obtained are summarised. (author)

Water quality, sources of nitrate, and chemical loadings in the Geronimo Creek and Plum Creek watersheds, south-central Texas, April 2015–March 2016

Science.gov (United States)

Lambert, Rebecca B.; Opsahl, Stephen P.; Musgrove, MaryLynn

2017-12-22

Located in south-central Texas, the Geronimo Creek and Plum Creek watersheds have long been characterized by elevated nitrate concentrations. From April 2015 through March 2016, an assessment was done by the U.S. Geological Survey, in cooperation with the Guadalupe-Blanco River Authority and the Texas State Soil and Water Conservation Board, to characterize nitrate concentrations and to document possible sources of elevated nitrate in these two watersheds. Water-quality samples were collected from stream, spring, and groundwater sites distributed across the two watersheds, along with precipitation samples and wastewater treatment plant (WWTP) effluent samples from the Plum Creek watershed, to characterize endmember concentrations and isotopic compositions from April 2015 through March 2016. Stream, spring, and groundwater samples from both watersheds were collected during four synoptic sampling events to characterize spatial and temporal variations in water quality and chemical loadings. Water-quality and -quantity data from the WWTPs and stream discharge data also were considered. Samples were analyzed for major ions, selected trace elements, nutrients, and stable isotopes of water and nitrate.The dominant land use in both watersheds is agriculture (cultivated crops, rangeland, and grassland and pasture). The upper part of the Plum Creek watershed is more highly urbanized and has five major WWTPs; numerous smaller permitted wastewater outfalls are concentrated in the upper and central parts of the Plum Creek watershed. The Geronimo Creek watershed, in contrast, has no WWTPs upstream from or near the sampling sites.Results indicate that water quality in the Geronimo Creek watershed, which was evaluated only during base-flow conditions, is dominated by groundwater, which discharges to the stream by numerous springs at various locations. Nitrate isotope values for most Geronimo Creek samples were similar, which indicates that they likely have a common source (or

Investigation on the effect of heavy diesel fraction properties on product sulphur during ultra deep diesel hydrodesulphurization

Energy Technology Data Exchange (ETDEWEB)

Stratiev, D.; Tzingov, T. [Research and Development Dept., Lukoil Neftochim Bourgas, Bourgas (Bulgaria); Galkin, V. [Future Development Dept., Lukoil Neftochim Bourgas, Bourgas (Bulgaria)

2006-02-01

This work investigates the hydrotreatment of heavy diesel fractions in order to achieve product sulphurs of 50 and 10 ppm. The heavy diesel fractions were obtained in the Lukoil Neftochim Bulgaria (LNB) crude distillation and vacuum distillation units (SRGO1, SRGO2, AGO, LVGO ASTM D-86 95%vol. of 360, 392 395, and 377 C respectively) by distillation of crude oil type ''Ural'', containing some quantities of naphtha, atmospheric residue, vacuum gas oil and low sulphur crude oil, in the mild hydrocracking unit (MHC diesel 95%vol. of 389 C) and in the fluid catalytic cracking unit - heavy cycle oil (FCC HCO; 95%vol. of 360 C). The diesel fractions were hydrotreated in a trickle bed pilot plant at following conditions: reactor inlet temperature range of 300-380 C; liquid hourly space velocity (LHSV) range of 0.5-3.0 h{sup -1}, total reactor pressure range of 3.5- 7.0 MPa; treating gas/feedstock ratio of 250 Nm{sup 3}/m{sup 3}. It was found that in the investigated range of operating conditions the product sulphur depended linearly on the LHSV. As a measure of the diesel hydrodesulphurization (HDS) reactivity the LHSV at 360 C reactor inlet temperature was interpolated at a constant product sulphur level of 50 ppm and extrapolated at 10 ppm sulphur. It was found that the most refractory feedstock was the diesel mixture 80%SRGO1 / 20%FCCHCO (LHSV of 0.4 h{sup -1} for 50 ppm and 0.2 h{sup -1} for 10 ppm sulphur). The catalyst volume increase required to reduce the product sulphur from 50 to 10 ppm was found to be as high as twice for all diesel fractions except the MHC diesel. This material required five times the catalyst volume for the product sulphur reduction from 50 to 10 ppm. The total reactor pressure was found to have less impact on the product sulphur than the LHSV. Doubling the reactor pressure from 3.5 to 7.0 MPa by hydrotreatment of LVGO reduced the product sulphur as low as twice while the reduction of the LHSV from 1 to 0.5 h{sup -1} at a

Computational modeling of lava domes using particle dynamics to investigate the effect of conduit flow mechanics on flow patterns

Science.gov (United States)

Husain, Taha Murtuza

Large (1--4 x 106 m3) to major (> 4 x 106 m3) dome collapses for andesitic lava domes such as Soufriere Hills Volcano, Montserrat are observed for elevated magma discharge rates (6--13 m3/s). The gas rich magma pulses lead to pressure build up in the lava dome that result in structural failure of the over steepened canyon-like walls which may lead to rockfall or pyroclastic flow. This indicates that dome collapse intimately related to magma extrusion rate. Variation in magma extrusion rate for open-system magma chambers is observed to follow alternating periods of high and low activity. Periodic behavior of magma exhibits a rich diversity in the nature of its eruptive history due to variation in magma chamber size, total crystal content, linear crystal growth rate and magma replenishment rate. Distinguished patterns of growth were observed at different magma flow rates ranging from endogenous to exogenous dome growth for magma with varying strengths. Determining the key parameters that control the transition in flow pattern of the magma during its lava dome building eruption is the main focus. This dissertation examines the mechanical effects on the morphology of the evolving lava dome on the extrusion of magma from a central vent using a 2D particle dynamics model. The particle dynamics model is coupled with a conduit flow model that incorporates the kinetics of crystallization and rheological stiffening to investigate important mechanisms during lava dome building eruptions. Chapter I of this dissertation explores lava dome growth and failure mechanics using a two-dimensional particle-dynamics model. The model follows the evolution of fractured lava, with solidification driven by degassing induced crystallization of magma. The particle-dynamics model emulates the natural development of dome growth and rearrangement of the lava dome which is difficult in mesh-based analyses due to mesh entanglement effects. The deformable talus evolves naturally as a frictional

Sensibility analysis of VORIS lava-flow simulations: application to Nyamulagira volcano, Democratic Republic of Congo

Science.gov (United States)

Syavulisembo, A. M.; Havenith, H.-B.; Smets, B.; d'Oreye, N.; Marti, J.

2015-03-01

Assessment and management of volcanic risk are important scientific, economic, and political issues, especially in densely populated areas threatened by volcanoes. The Virunga area in the Democratic Republic of Congo, with over 1 million inhabitants, has to cope permanently with the threat posed by the active Nyamulagira and Nyiragongo volcanoes. During the past century, Nyamulagira erupted at intervals of 1-4 years - mostly in the form of lava flows - at least 30 times. Its summit and flank eruptions lasted for periods of a few days up to more than two years, and produced lava flows sometimes reaching distances of over 20 km from the volcano, thereby affecting very large areas and having a serious impact on the region of Virunga. In order to identify a useful tool for lava flow hazard assessment at the Goma Volcano Observatory (GVO), we tested VORIS 2.0.1 (Felpeto et al., 2007), a freely available software (http://www.gvb-csic.es) based on a probabilistic model that considers topography as the main parameter controlling lava flow propagation. We tested different Digital Elevation Models (DEM) - SRTM1, SRTM3, and ASTER GDEM - to analyze the sensibility of the input parameters of VORIS 2.0.1 in simulation of recent historical lava-flow for which the pre-eruption topography is known. The results obtained show that VORIS 2.0.1 is a quick, easy-to-use tool for simulating lava-flow eruptions and replicates to a high degree of accuracy the eruptions tested. In practice, these results will be used by GVO to calibrate VORIS model for lava flow path forecasting during new eruptions, hence contributing to a better volcanic crisis management.

Past and future trends in concentrations of sulphur and nitrogen compounds in the Arctic

DEFF Research Database (Denmark)

Hole, Lars R.; Christensen, Jesper H.; Ruoho-Airola, Tuija

2009-01-01

Recent trends in nitrogen and sulphur compounds in air and precipitation from a range of Arctic monitoring stations are presented, with seasonal data from the late 70s to 2004 or 2005. Earlier findings of declining sulphur concentrations are confirmed for most stations, while the pattern is less ...

A sinuous tumulus over an active lava tube at Kīlauea Volcano: Evolution, analogs, and hazard forecasts

Science.gov (United States)

Orr, Tim R.; Bleacher, Jacob E.; Patrick, Matthew R.; Wooten, Kelly M.

2015-01-01

Inflation of narrow tube-fed basaltic lava flows (tens of meters across), such as those confined by topography, can be focused predominantly along the roof of a lava tube. This can lead to the development of an unusually long tumulus, its shape matching the sinuosity of the underlying lava tube. Such a situation occurred during Kīlauea Volcano's (Hawai'i, USA) ongoing East Rift Zone eruption on a lava tube active from July through November 2010. Short-lived breakouts from the tube buried the flanks of the sinuous, ridge-like tumulus, while the tumulus crest, its surface composed of lava formed very early in the flow's emplacement history, remained poised above the surrounding younger flows. At least several of these breakouts resulted in irrecoverable uplift of the tube roof. Confined sections of the prehistoric Carrizozo and McCartys flows (New Mexico, USA) display similar sinuous, ridge-like features with comparable surface age relationships. We contend that these distinct features formed in a fashion equivalent to that of the sinuous tumulus that formed at Kīlauea in 2010. Moreover, these sinuous tumuli may be analogs for some sinuous ridges evident in orbital images of the Tharsis volcanic province on Mars. The short-lived breakouts from the sinuous tumulus at Kīlauea were caused by surges in discharge through the lava tube, in response to cycles of deflation and inflation (DI events) at Kīlauea's summit. The correlation between DI events and subsequent breakouts aided in lava flow forecasting. Breakouts from the sinuous tumulus advanced repeatedly toward the sparsely populated Kalapana Gardens subdivision, destroying two homes and threatening others. Hazard assessments, including flow occurrence and advance forecasts, were relayed regularly to the Hawai'i County Civil Defense to aid their lava flow hazard mitigation efforts while this lava tube was active.

A sinuous tumulus over an active lava tube at Kīlauea Volcano: evolution, analogs, and hazard forecasts

Science.gov (United States)

Orr, Tim R.; Bleacher, Jacob E.; Patrick, Matthew R.; Wooten, Kelly M.

2015-01-01

Inflation of narrow tube-fed basaltic lava flows (tens of meters across), such as those confined by topography, can be focused predominantly along the roof of a lava tube. This can lead to the development of an unusually long tumulus, its shape matching the sinuosity of the underlying lava tube. Such a situation occurred during Kīlauea Volcano's (Hawai'i, USA) ongoing East Rift Zone eruption on a lava tube active from July through November 2010. Short-lived breakouts from the tube buried the flanks of the sinuous, ridge-like tumulus, while the tumulus crest, its surface composed of lava formed very early in the flow's emplacement history, remained poised above the surrounding younger flows. At least several of these breakouts resulted in irrecoverable uplift of the tube roof. Confined sections of the prehistoric Carrizozo and McCartys flows (New Mexico, USA) display similar sinuous, ridge-like features with comparable surface age relationships. We contend that these distinct features formed in a fashion equivalent to that of the sinuous tumulus that formed at Kīlauea in 2010. Moreover, these sinuous tumuli may be analogs for some sinuous ridges evident in orbital images of the Tharsis volcanic province on Mars. The short-lived breakouts from the sinuous tumulus at Kīlauea were caused by surges in discharge through the lava tube, in response to cycles of deflation and inflation (DI events) at Kīlauea's summit. The correlation between DI events and subsequent breakouts aided in lava flow forecasting. Breakouts from the sinuous tumulus advanced repeatedly toward the sparsely populated Kalapana Gardens subdivision, destroying two homes and threatening others. Hazard assessments, including flow occurrence and advance forecasts, were relayed regularly to the Hawai'i County Civil Defense to aid their lava flow hazard mitigation efforts while this lava tube was active.

Catalysts macroporosity and their efficiency in sulphur sub-dew point Claus tail gas treating processes

Energy Technology Data Exchange (ETDEWEB)

Tsybulevski, A.M.; Pearson, M. [Alcoa Industrial Chemicals, 16010 Barker`s Point Lane, Houston, TX (United States); Morgun, L.V.; Filatova, O.E. [All-Russian Research Institute of Natural Gases and Gas Technologies VNIIGAZ, Moscow (Russian Federation); Sharp, M. [Porocel Corporation, Westheimer, Houston, TX (United States)

1996-10-08

The efficiency of 4 samples of alumina catalyst has been studied experimentally in the course of the Claus `tail gas` treating processes at the sulphur sub-dew point (TGTP). The samples were characterized by the same chemical and crystallographic composition, the same volume of micropores, the same surface area and the same catalytic activity but differed appreciably in the volume of macropores. An increase in the effective operation time of the catalysts before breakthrough of unrecoverable sulphur containing compounds, with the increasing macropore volume has been established. A theoretical model of the TGTP has been considered and it has been shown that the increase in the sulphur capacity of the catalysts with a larger volume of macropores is due to an increase in the catalysts efficiency factor and a slower decrease in their diffusive permeability during filling of micropores by sulphur

33 CFR 117.1001 - Cat Point Creek.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Cat Point Creek. 117.1001 Section 117.1001 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Virginia § 117.1001 Cat Point Creek. The draw of the...

33 CFR 117.705 - Beaver Dam Creek.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Beaver Dam Creek. 117.705 Section 117.705 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.705 Beaver Dam Creek. The draw of the...

33 CFR 117.800 - Mill Neck Creek.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Mill Neck Creek. 117.800 Section 117.800 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New York § 117.800 Mill Neck Creek. The draw of the...

Simultaneous analyses of gaseous and particulate sulphur compounds in the atmosphere by x-ray fluorescence spectrometry, (1)

International Nuclear Information System (INIS)

Matsuda, Yatsuka; Mamuro, Tetsuo

1974-01-01

An analytical technique for the simultaneous measurements of the atmospheric concentrations of SO 2 gas and sulphur absorbed by aerosol particles has been developed. Aerosol particles are collected on membrane filter and at the same time SO 2 gas is captured on alkali impregnated filter. The sulphur content in each filter is measured by an energy dispersive X-ray fluorescence spectrometer consisting of a Si(Li) semiconductor detector connected to a multichannel pulse hight analyzer and an excitation source of 55 Fe. Two methods are acceptable for the determination of the sulphur content in impregnated filter by X-ray fluorescence analysis. In the first method X-ray fluorescence analysis is made after the collected sulphur has diffused and distributed uniformly enough throughout filter, and in the second method X-ray fluorescence analysis has to be finished before the diffusion of the collected sulphur becomes appreciable. (auth.)

A frozen record of density-driven crustal overturn in lava lakes: The example of Kilauea Iki 1959

Science.gov (United States)

Stovall, W.K.; Houghton, Bruce F.; Harris, A.J.L.; Swanson, D.A.

2009-01-01

Lava lakes are found at basaltic volcanoes on Earth and other planetary bodies. Density-driven crustal foundering leading to surface renewal occurs repeatedly throughout the life of a lava lake. This process has been observed and described in a qualitative sense, but due to dangerous conditions, no data has been acquired to evaluate the densities of the units involved. Kilauea Iki pit crater in Hawai'i houses a lava lake erupted during a 2 month period in 1959. Part of the surface of the Kilauea Iki lake now preserves the frozen record of a final, incomplete, crustal-overturn cycle. We mapped this region and sampled portions of the foundering crust, as well as overriding and underlying lava, to constrain the density of the units involved in the overturn process. Overturn is driven by the advance of a flow front of fresh, low-density lava over an older, higher density surface crust. The advance of the front causes the older crust to break up, founder, and dive downwards into the lake to expose new, hot, low-density lava. We find density differences of 200 to 740 kg/m3 between the foundering crust and over-riding and under-lying lava respectively. In this case, crustal overturn is driven by large density differences between the foundering and resurfacing units. These differences lead, inevitably, to frequent crustal renewal: simple density differences between the surface crust and underlying lake lava make the upper layers of the lake highly unstable. ?? Springer-Verlag 2008.

The remaining percentage of 32P after burning of sulphur tablet containing 32P

International Nuclear Information System (INIS)

Ke Weiqing

1991-01-01

Three types of sulphur tablet containing 32 P are made artificially. The remaining percentage of 32 P after burning of three types of sulphur tablets containing 32 P is 98.1 ± 1.3% for 1st and 2nd types and 97.2 ± 2.8% for 3rd type

Effect of NPK fertilization and elemental sulphur on growth and yield of lowbush blueberry

Directory of Open Access Journals (Sweden)

M. STARAST

2008-12-01

Full Text Available The aim of the research was to determine the effect of fertilizers on the pH of former arable soils and on the growth and the yield of the lowbush blueberry (Vaccinium angustifolium Ait.. Lowbush blueberry fertilization experiments were established in 1999 at two locations – at Kärla, Saaremaa, West Estonia and at Vasula, Tartu County, South Estonia. Experimental sites were situated on different soils: soil pHKCl at Kärla was 5.5 and at Vasula 6.2. Elemental sulphur and acidifying fertilizers (ammonium sulfate, potassium sulfate and superphosphate were used in both plantations. Fertilizers were applied based on nutrient in the soil and sulphur was applied at 100 g m–2. Plant growth was recorded in 2001, 2002 and 2003. A positive influence of NPK fertilization on yield was found in both Kärla and Vasula, and yield were 336 g and 41 g higher compared to the control, respectively. The vegetative growth and yield of blueberry depended significantly on soil pH. Elemental sulphur increased soil acidity and on loamy sand soil did not increase plant productivity. The sulphur effect on soil pH began to decrease three years after application. Sulphur can be recommended to increase soil acidity in nutrient-rich soil but, not nutrient poor soil with light texture, where only NPK fertilizers were effective.;

Elevation - LiDAR Survey Minnehaha Creek, MN Watershed

Data.gov (United States)

Army Corps of Engineers, Department of the Army, Department of Defense — LiDAR Bare-Earth Grid - Minnehaha Creek Watershed District. The Minnehaha Creek watershed is located primarily in Hennepin County, Minnesota. The watershed covers...

Trading sulphur emissions under the Second Sulphur Protocol

Energy Technology Data Exchange (ETDEWEB)

Foersund, Finn R.; Naevdal, Eric

1997-07-01

Emission trading is a potent policy instrument in theoretical analyses of environmental policy. However, trading in emission quotas of non-uniformly dispersed pollutants requires that the offsetting quantities vary with location of sources. Such a system is not yet in use. The Second Sulphur Protocol for Europe makes it possible to try out a system of ``exchange rates`` through a clause allowing ``joint implementation`` of emission reductions. In this report, the authors investigate some properties of a system with exogenous exchange rates within a simultaneous trade model based on cost efficiency. Incorporation of constraints on depositions in third party countries may be necessary in order to get third party country cooperation. It is demonstrated that imposition of constraints is feasible, but it is also revealed what demands such incorporation places on the design of the institutional setting. Constraints on trade should only be introduced when the concern for the environment of the various receptors fail to be captured adequately by the calibration of the exchange rates. 16 refs., 2 figs., 3 tabs.

Study of the thermoluminescent properties of lava from different origins; Estudio de las propiedades termoluminiscentes de lavas de diferentes origenes

Energy Technology Data Exchange (ETDEWEB)

Molina, D. [Centro de Proteccion e Higiene de las Radiaciones, A.P. 6195, C.P. 10600, La Habana (Cuba); Correcher, V.; Delgado, A. [CIEMAT. Dosimetria de Radiaciones, Av. Complutense 22, Madrid 28040 (Spain); Garcia G, J. [CSIC. Museo Nacional de Ciencias Naturales, C/Jose Gutierrez Abascal 2. Madrid 28006 (Spain)

2002-07-01

In this work has been studied the thermoluminescent signal (Tl) of lava from different geographical area (Costa Rica, the Canary Islands, Hawaii, Iceland and Italy) and originating in distinct eruptions, for its possible use such as in the dating field (geological and archaeological) as in retrospective dosimetry. Due that the light emission is intimately related with the punctual defects existent in the structure of material associated to the presence of different mineral phases, it was realized a study by X-ray diffraction for determining the main components of the lava observing the presence, in distinct proportions of cristobalite, plagioclases (chalcosodic feldspars) and philosilicates (augite, montmorillonite, forsterite and actinolite). All the detected mineral components present Tl emission in the blue region. Each one of the lava were artificially irradiated for proving the dependence of the luminescent signal with the dose in the range 1 to 25 Gy, observing a linear response with the dose in all the cases and not appreciating saturation in the Tl emission. Such the appropriate signal of natural samples (TLN) as the irradiated samples in the laboratory (TLI) show a complex structure associated with a continuous distribution of traps at temperature higher than 100 C which could be explained as consequence of the dynamic formation-annihilation of centers [AlO{sub 4}/alkali]{sup +} and [AlO{sub 4}]{sup 0}. In TLI was observed that a nearer to 85 C appeared a maximum whose structure correspond a discrete distribution of traps, coexisting therefore the two types of traps structure. (Author)

Subduction Contributions in the Trans-Mexican Volcanic Belt: Implications from Lava Chemistry and Hf-Nd-Pb Isotopes

Science.gov (United States)

Cai, Y.; Goldstein, S. L.; Langmuir, C. H.; Gómez-Tuena, A.; Lagatta, A.; Straub, S. M.; Martín Del Pozzo, A.

2007-05-01

Despite thick continental crust, near primitive lavas erupt throughout the Trans-Mexican Volcanic Belt (TMVB). In order to distinguish and better constrain subduction contributions and effects of crustal contamination, we analyzed samples representing subducting sediments from DSDP Site 487, and Quaternary lavas from stratovolcanoes and cinder cones, including alkaline "high-Nb" lavas from the Sierra Chichinautzin Volcanic Field (SCVF) showing negligible subduction signature in its trace element chemistry and representing melts of the mantle wedge. Our primary observations and implications are: (1) The high-Nb SCVF `intraplate' lavas define a linear trend along the "Nd-Hf mantle-crust array", defining the composition of the mantle wedge. (2) Popocatepetl and Nevado de Toluca stratovolcanoes show the highest Nd and Hf isotope ratios, higher than the `intraplate' lavas, indicating their sources are more "depleted mantle-like" than the regional mantle wedge. (3) The Popo and Toluca chemical and isotopic trends sharply contrast with Pico de Orizaba, which shows classic indications of crustal contamination (e.g. high 207Pb/204Pb, low Nd-Hf isotope ratios), consistent with contamination by local Precambrian crust. (4) Higher Nd-Hf isotopes in Popo and Toluca lavas also correlate with lower Pb isotope ratios, and lower Lu/Hf and Zr/Hf. Together, these data indicate contributions from subducted Pacific oceanic crust and hydrothermal sediment. (5) Popo and Toluca are also enriched in Th/LREE compared with `intraplate' lavas, reflecting subducted sediment contributions. (6) Nd-Hf isotope ratios of hydrothermal sediment from DSDP Site 487 lie on the "seawater array", with high Hf isotope ratios compared to the "mantle-crust array". Popo and Toluca Nd-Hf isotopes display a shallower slope than the "intraplate lava Nd-Hf array", reflecting contributions from hydrothermal sediment. Popocatepetl and Toluca lavas therefore avoid substantial crustal contamination of mantle wedge

Benchmarking computational fluid dynamics models of lava flow simulation for hazard assessment, forecasting, and risk management

Science.gov (United States)

Dietterich, Hannah; Lev, Einat; Chen, Jiangzhi; Richardson, Jacob A.; Cashman, Katharine V.

2017-01-01

Numerical simulations of lava flow emplacement are valuable for assessing lava flow hazards, forecasting active flows, designing flow mitigation measures, interpreting past eruptions, and understanding the controls on lava flow behavior. Existing lava flow models vary in simplifying assumptions, physics, dimensionality, and the degree to which they have been validated against analytical solutions, experiments, and natural observations. In order to assess existing models and guide the development of new codes, we conduct a benchmarking study of computational fluid dynamics (CFD) models for lava flow emplacement, including VolcFlow, OpenFOAM, FLOW-3D, COMSOL, and MOLASSES. We model viscous, cooling, and solidifying flows over horizontal planes, sloping surfaces, and into topographic obstacles. We compare model results to physical observations made during well-controlled analogue and molten basalt experiments, and to analytical theory when available. Overall, the models accurately simulate viscous flow with some variability in flow thickness where flows intersect obstacles. OpenFOAM, COMSOL, and FLOW-3D can each reproduce experimental measurements of cooling viscous flows, and OpenFOAM and FLOW-3D simulations with temperature-dependent rheology match results from molten basalt experiments. We assess the goodness-of-fit of the simulation results and the computational cost. Our results guide the selection of numerical simulation codes for different applications, including inferring emplacement conditions of past lava flows, modeling the temporal evolution of ongoing flows during eruption, and probabilistic assessment of lava flow hazard prior to eruption. Finally, we outline potential experiments and desired key observational data from future flows that would extend existing benchmarking data sets.

Density of states of adsorbed sulphur atoms on pristine and defective graphene layers

International Nuclear Information System (INIS)

Arellano, J S

2017-01-01

The density of states for adsorbed sulphur atom on a graphene layer system is discussed for pristine graphene layer and for mono and divacancies on the graphene layer. To our knowledge this is the first time that an entire adsorption of the sulphur atom is reported at the plane of the carbon atoms, when there is a pair of closer vacancies at the graphene layer. (paper)

Sulphur chemistry in the L1544 pre-stellar core

Science.gov (United States)

Vastel, Charlotte; Quénard, D.; Le Gal, R.; Wakelam, V.; Andrianasolo, A.; Caselli, P.; Vidal, T.; Ceccarelli, C.; Lefloch, B.; Bachiller, R.

2018-05-01

The L1544 pre-stellar core has been observed as part of the ASAI IRAM 30m Large Program as well as follow-up programs. These observations have revealed the chemical richness of the earliest phases of low-mass star-forming regions. In this paper we focus on the twenty-one sulphur bearing species (ions, isotopomers and deuteration) that have been detected in this spectral-survey through fifty one transitions: CS, CCS, C3S, SO, SO2, H2CS, OCS, HSCN, NS, HCS+, NS+ and H2S. We also report the tentative detection (4 σ level) for methyl mercaptan (CH3SH). LTE and non-LTE radiative transfer modelling have been performed and we used the NAUTILUS chemical code updated with the most recent chemical network for sulphur to explain our observations. From the chemical modelling we expect a strong radial variation for the abundances of these species, which mostly are emitted in the external layer where non thermal desorption of other species has previously been observed. We show that the chemical study cannot be compared to what has been done for the TMC-1 dark cloud, where the abundance is supposed constant along the line of sight, and conclude that a strong sulphur depletion is necessary to fully reproduce our observations of the prototypical pre-stellar core L1544.

Key variables influencing patterns of lava dome growth and collapse

Science.gov (United States)

Husain, T.; Elsworth, D.; Voight, B.; Mattioli, G. S.; Jansma, P. E.

2013-12-01

Lava domes are conical structures that grow by the infusion of viscous silicic or intermediate composition magma from a central volcanic conduit. Dome growth can be characterized by repeated cycles of growth punctuated by collapse, as the structure becomes oversized for its composite strength. Within these cycles, deformation ranges from slow long term deformation to sudden deep-seated collapses. Collapses may range from small raveling failures to voluminous and fast-moving pyroclastic flows with rapid and long-downslope-reach from the edifice. Infusion rate and magma rheology together with crystallization temperature and volatile content govern the spatial distribution of strength in the structure. Solidification, driven by degassing-induced crystallization of magma leads to the formation of a continuously evolving frictional talus as a hard outer shell. This shell encapsulates the cohesion-dominated soft ductile core. Here we explore the mechanics of lava dome growth and failure using a two-dimensional particle-dynamics model. This meshless model follows the natural evolution of a brittle carapace formed by loss of volatiles and rheological stiffening and avoids difficulties of hour-glassing and mesh-entangelment typical in meshed models. We test the fidelity of the model against existing experimental and observational models of lava dome growth. The particle-dynamics model follows the natural development of dome growth and collapse which is infeasible using simple analytical models. The model provides insight into the triggers that lead to the transition in collapse mechasnism from shallow flank collapse to deep seated sector collapse. Increase in material stiffness due to decrease in infusion rate results in the transition of growth pattern from endogenous to exogenous. The material stiffness and strength are strongly controlled by the magma infusion rate. Increase in infusion rate decreases the time available for degassing induced crystallization leading to a

Lava Tubes as Martian Analog sites on Hawaii Island

Science.gov (United States)

Andersen, Christian; Hamilton, J. C.; Adams, M.

2013-10-01

The existence of geologic features similar to skylights seen in Mars Reconnaissance Orbiter HIRISE imagery suggest Martian lava tube networks. Along with pit craters, these features are evidence of a past era of vulcanism. If these were contemporary with the wet Mars eras, then it is suggestive that any Martian life may have retreated into these subsurface oases. Hawaii island has numerous lava tubes of differing ages, humidity, lengths and sizes that make ideal analog test environments for future Mars exploration. PISCES has surveyed multiple candidate sites during the past summer with a team of University of Hawaii at Hilo student interns. It should be noted that Lunar features have also been similarly discovered via Lunar Reconnaissance Orbiter LROC imagery.

Preliminary Chemical and Biological Assessment of Ogbe Creek ...

African Journals Online (AJOL)

USER

The study was aimed at assessing the quality of water from the Ogbe Creek ... indicated the impact of the perturbational stress on the organisms inhabiting the creek. ... experiences seasonal flooding which introduces a lot of detritus and ...

Plankton biodiversity of Dharamtar creek adjoining Mumbai harbour

Digital Repository Service at National Institute of Oceanography (India)

Tiwari, L.R.; Nair, V.R.

rich plankton community. However, recent industrial development along the banks of creek may pose the problem due to waste disposal into this creek system. Losses of marine life diversity are largely the results of conflicting uses, in particular...

Influence of sulphur and phosphorus on the hot deformation of Fe-Cr 13% high purity steel

International Nuclear Information System (INIS)

Lahreche, M.; Bouzabata, B.; Kobylanski, A.

1995-01-01

A series of Fe-Cr13%-C high purity steels containing increasing volume fractions of Sulphur (30, 60 and 100ppm) and Phosphorus (30, 60 and 100ppm) were prepared in order to study their hot deformation properties by tensile tests at various strain rates (10 -1 s -1 to 10 -4 s -1 ) and at temperatures from 700 C to 1100 C. It is observed that the hot ductility is lowered at 1000 C with the addition of sulphur. However, this decrease is relatively small (about 30% for 100ppm of sulphur) and quite similar for all additions of sulphur. When phosphorus is added, the embrittlement is along the whole deformed specimen. The usual criteria of ductility by parameter Z do not seem to be sufficient to describe this embrittlement. (orig.)

Dry deposition of sulphur on the Mpumalanga highveld: a pilot study using the inferential method

CSIR Research Space (South Africa)

Zunckel, M

1996-10-01

Full Text Available contributions come from SO2 at night and from particulates during the day in both seasons. The contribution to the total dry deposition sulphur load by particulates at night appears to be negligible. Assuming that sulphur precipitation for the two monitoring...

In situ NIR reflectance and LIBS measurements in lava tubes in preparation for future Mars missions

Science.gov (United States)

Leveille, R.; Sobron, P.

2017-12-01

The ATiLT (Astrobiology Training in Lava Tubes) program addresses Mars astrobiology exploration objectives by performing field work and instrumental analyses in lava tubes as high fidelity analog environments to putative lava tubes on Mars. The main field location for ATiLT is the Lava Beds National Monument (LABE) in Northern California. LABE is situated on the lower north flank of the Medicine Lake Volcano of the Cascade arc. This location features hundreds of caves, most of which are relatively shallow, typically well above the water table, reaching 20-45m below land surface at their maximum depth. Some LABE caves feature `cold sinks' where cold air sinks and becomes trapped in deeper cave passages, thus allowing perennial ice to accumulate despite above freezing surface temperatures. Several lava tube caves in LABE also contain seasonal or perennial ice accumulations, which makes them excellent analogs to Mars lava tubes where the presence of ice has been predicted. While lava tubes are very attractive systems to test hypotheses related to habitability and the possibility for life on Mars, at present there are no comprehensive in-situ instrument-driven characterizations of the mineralogy and geochemistry of lava tubes. ATiLT fills this gap by providing detailed, in-situ investigations with scientific instruments relevant to Mars exploration. Our aim is to help constrain future exploration targets on Mars and define future mission operations and requirements. For this purpose, in May 2017 we carried out a field campaign in several lava tubes at LABE. We deployed two miniature spectroscopic sensors suitable for dark, humid, cave conditions: NIR reflectance (1-5 μm) and LIBS (300-900 nm). The advantages of combining NIR reflectance and LIBS are evident: LIBS can reveal the relative concentration of major (and often trace) elements present in a bulk sample, whereas NIR reflectance yields information on the individual mineral species and their chemical and

77 FR 5201 - Drawbridge Operation Regulation; Bear Creek, Dundalk, MD

Science.gov (United States)

2012-02-02

...-AA09 Drawbridge Operation Regulation; Bear Creek, Dundalk, MD AGENCY: Coast Guard, DHS. ACTION: Notice... operation of the Baltimore County highway bridge at Wise Avenue across Bear Creek, mile 3.4, between Dundalk... Avenue across Bear Creek, mile 3.4 between Dundalk and Sparrows Point, MD. This change would require the...

Effects of sulphur addition on modification and mechanical ...

African Journals Online (AJOL)

CW Onyia, BA Okorie, NI Amalu, SI Neife ... The results showed that the addition of sulphur to Al-12wt%Si alloy modified the Al-Si eutectic ... of the eutectic silicon structure with significant decrease in mechanical properties of the alloy and this ...

Separation of uranium, molibdenum and vanadium in sulphuric solutions by extraction with alamine 336

International Nuclear Information System (INIS)

Floh, B.

1976-01-01

Alamine 336 - varsol - sulphuric acid-water system used for uranium, molibdenum and vanadium extraction, from sulphuric leaching and an appropriate plan for fractioning those elements are investigated. The behavior of cited elements in pure solutions followed by interaction that occurs in both bynary and tertiary systems are studied. Distribution coefficient is regarded for measuring such effects [pt

Seasonal and annual variability of coastal sulphur plumes in the northern Benguela upwelling system.

Directory of Open Access Journals (Sweden)

Thomas Ohde

Full Text Available We investigated the seasonal and annual variability of surface sulphur plumes in the northern Benguela upwelling system off Namibia because of their significant impacts on the marine ecosystem, fishing industry, aquaculture farming and tourism due to their toxic properties. We identified the sulphur plumes in ocean colour satellite data of the medium resolution imaging spectrometer (MERIS for the 2002-2012 time period using the differences in the spectral properties of Namibian Benguela optical water types. The sulphur events have a strong seasonal cycle with pronounced main and off-seasons forced by local and remote-driven processes. The main peak season is in late austral summer and early austral autumn at the beginning of the annual upwelling cycle caused by increasing equatorwards alongshore winds. The sulphur plume activity is high between February and April during the seasonal oxygen minimum associated with the seasonal reduction of cross-shore ventilation of the bottom waters, the seasonal southernmost position of the Angola Benguela Frontal Zone, the seasonal maximum of water mass fractions of South Atlantic and Angola Gyre Central Waters as well as the seasonal arrival of the downwelling coastal trapped waves. The off-season is in austral spring and early austral summer during increased upwelling intensity and enhanced oxygen supply. The annual variability of sulphur events is characterized by very high activities in years 2004, 2005 and 2010 interrupted by periods of lower activity in years 2002 to 2003, 2006 to 2009 and 2011 to 2012. This result can be explained by the relative contributions or adding effects of local and remote-driven forces (from the equatorial area. The probability for the occurrence of sulphur plumes is enhanced in years with a lower annual mean of upwelling intensity, decreased oxygen supply associated with decreased lateral ventilation of bottom waters, more southern position of the Angola Benguela Frontal Zone

Seasonal and annual variability of coastal sulphur plumes in the northern Benguela upwelling system.

Science.gov (United States)

Ohde, Thomas; Dadou, Isabelle

2018-01-01

We investigated the seasonal and annual variability of surface sulphur plumes in the northern Benguela upwelling system off Namibia because of their significant impacts on the marine ecosystem, fishing industry, aquaculture farming and tourism due to their toxic properties. We identified the sulphur plumes in ocean colour satellite data of the medium resolution imaging spectrometer (MERIS) for the 2002-2012 time period using the differences in the spectral properties of Namibian Benguela optical water types. The sulphur events have a strong seasonal cycle with pronounced main and off-seasons forced by local and remote-driven processes. The main peak season is in late austral summer and early austral autumn at the beginning of the annual upwelling cycle caused by increasing equatorwards alongshore winds. The sulphur plume activity is high between February and April during the seasonal oxygen minimum associated with the seasonal reduction of cross-shore ventilation of the bottom waters, the seasonal southernmost position of the Angola Benguela Frontal Zone, the seasonal maximum of water mass fractions of South Atlantic and Angola Gyre Central Waters as well as the seasonal arrival of the downwelling coastal trapped waves. The off-season is in austral spring and early austral summer during increased upwelling intensity and enhanced oxygen supply. The annual variability of sulphur events is characterized by very high activities in years 2004, 2005 and 2010 interrupted by periods of lower activity in years 2002 to 2003, 2006 to 2009 and 2011 to 2012. This result can be explained by the relative contributions or adding effects of local and remote-driven forces (from the equatorial area). The probability for the occurrence of sulphur plumes is enhanced in years with a lower annual mean of upwelling intensity, decreased oxygen supply associated with decreased lateral ventilation of bottom waters, more southern position of the Angola Benguela Frontal Zone, increased mass

LAVA: Large scale Automated Vulnerability Addition

Science.gov (United States)

2016-05-23

LAVA: Large-scale Automated Vulnerability Addition Brendan Dolan -Gavitt∗, Patrick Hulin†, Tim Leek†, Fredrich Ulrich†, Ryan Whelan† (Authors listed...released, and thus rapidly become stale. We can expect tools to have been trained to detect bugs that have been released. Given the commercial price tag...low TCN) and dead (low liveness) program data is a powerful one for vulnera- bility injection. The DUAs it identifies are internal program quantities

Controls on Lava Flow Morphology and Propagation: Using Laboratory Analogue Experiments

Science.gov (United States)

Peters, S.; Clarke, A. B.

2017-12-01

The morphology of lava flows is controlled by eruption rate, composition, cooling rate, and topography [Fink and Griffiths, 1990; Gregg and Fink, 2000, 2006]. Lava flows are used to understand how volcanoes, volcanic fields, and igneous provinces formed and evolved [Gregg and Fink., 1996; Sheth, 2006]. This is particularly important for other planets where compositional data is limited and historical context is nonexistent. Numerical modeling of lava flows remains challenging, but has been aided by laboratory analog experiments [Gregg and Keszrthelyi, 2004; Soule and Cashman, 2004]. Experiments using polyethylene glycol (PEG) 600 wax have been performed to understand lava flow emplacement [Fink and Griffiths, 1990, 1992; Gregg and Fink, 2000]. These experiments established psi (hereafter denoted by Ψ), a dimensionless parameter that relates crust formation and advection timescales of a viscous gravity current. Four primary flow morphologies corresponding to discreet Ψ ranges were observed. Gregg and Fink [2000] also investigated flows on slopes and found that steeper slopes increase the effective effusion rate producing predicted morphologies at lower Ψ values. Additional work is needed to constrain the Ψ parameter space, evaluate the predictive capability of Ψ, and determine if the preserved flow morphology can be used to indicate the initial flow conditions. We performed 514 experiments to address the following controls on lava flow morphology: slope (n = 282), unsteadiness/pulsations (n = 58), slope & unsteadiness/pulsations (n = 174), distal processes, and emplacement vs. post-emplacement morphologies. Our slope experiments reveal a similar trend to Gregg and Fink [2000] with the caveat that very high and very low local & source eruption rates can reduce the apparent predictive capability of Ψ. Predicted Ψ morphologies were often produced halfway through the eruption. Our pulse experiments are expected to produce morphologies unique to each eruption rate

Vertical Structural Variation and Their Development of the Sanukayama Rhyolite Lava in Kozushima Island, Japan

Science.gov (United States)

Furukawa, K.; Uno, K.; Kanamaru, T.; Nakai, K.

2017-12-01

We revealed structural development of the Pleistocene Sanukayama rhyolite lava of Kozushima Island, Japan. The good exposure, with about 130 m thick, provides valuable opportunity to understand the vertical structural variation. This exposure corresponds to the upper half of the lava. The paleomagnetic results show that the lava emplaced in subaerial condition at least in the exposed part. The vertical lithofacies are divided into the pumiceous (25-40 m thick), obsidian (40-60 m), spherulitic (30-50 m) layers from top to base. The pumiceous layer is characterized by massive foliated pumice. The foliation dips are gradually changed from gentle (10-30°) in lower part to steep (around 90°) in upper part. This shows the balloon-like morphology. The massive pumiceous layer would be generated from late stage diapiric inflation of the lava (Fink and Manley, 1987). The obsidian layer is composed of massive and welded-brecciated parts. The ductile-deformed light-colored veins, with a few mm thick, are frequently developed. In the microscopic observation, the veins are composed of broken crystals and obsidian clasts indicating fracturing of the lava followed by ductile deformation such as the RFH process (Tuffen et al., 2003). In this layer, extensive vesiculation and microlite development must have been prevented by higher load pressure and faster cooling, respectively. Consequently, they resulted in formation of the obsidian. The spherulitic layer is characterized by development of the ductile-deformed flow banding. The microscopic observation shows that the bands are formed by the spherulite trail. Furthermore, the microlites are aligned within the spherulites. In the heat-retained inner part of the lava, microlites would be developed around the healed fractures. The microlites acted as nucleation site of spherulite. In transition layer between obsidian and spherulitic layers (obsidian layer. This would be caused by high flow-induced shear arising from their rheological

The Etendeka lavas SWA/Namibia: geology, chemistry and spatial and temporal relationships

International Nuclear Information System (INIS)

Marsh, J.S.; Erlank, A.J.; Duncan, A.R.; Miller, R.McG.; Rex, D.C.

1981-01-01

The paper discusses a geologic survey on the Etendeka lavas in South West Africa/Namibia with special attention to the geology, chemistry and spatial and temporal relationships in the area. K/Ar age data indicate that the bulk of the Etendeka lavas are about 120 m.y. old. In the study use was also made of 87 Sr/ 86 Sr, 143 Nd/ 144 Nd, 206 Pb/ 204 Pb, 207 Pb/ 204 Pb and 208 Pb/ 204 Pb isotope ratios

Automated tracking of lava lake level using thermal images at Kīlauea Volcano, Hawai’i

Science.gov (United States)

Patrick, Matthew R.; Swanson, Don; Orr, Tim R.

2016-01-01

Tracking the level of the lava lake in Halema‘uma‘u Crater, at the summit of Kīlauea Volcano, Hawai’i, is an essential part of monitoring the ongoing eruption and forecasting potentially hazardous changes in activity. We describe a simple automated image processing routine that analyzes continuously-acquired thermal images of the lava lake and measures lava level. The method uses three image segmentation approaches, based on edge detection, short-term change analysis, and composite temperature thresholding, to identify and track the lake margin in the images. These relative measurements from the images are periodically calibrated with laser rangefinder measurements to produce real-time estimates of lake elevation. Continuous, automated tracking of the lava level has been an important tool used by the U.S. Geological Survey’s Hawaiian Volcano Observatory since 2012 in real-time operational monitoring of the volcano and its hazard potential.

Temporal and Spatial Variability in the Geochemistry of Axial and CoAxial Segment Lavas and their Mantle Sources

Science.gov (United States)

Smith, M. C.; Perfit, M. R.; Davis, C.; Kamenov, G. D.

2011-12-01

Three spatially related volcanic eruptions along the CoAxial Segment of the Juan de Fuca Ridge (JdFR) have documented emplacements between 1981 and 1993. Two of the historic flows outcrop at the "Flow Site" and were emplaced within less than 12 years and 500 m from one another. The third was emplaced at the "Floc Site" to the south in the 1980s. Previous studies have documented that CoAxial lavas are among the most incompatible element and isotopically depleted lavas along the entire JdFR, whereas the Axial Seamount segment immediately south of CoAxial has erupted the most chemically enriched lavas south of the Endeavor Segment. Geochemical studies have shown little temporal change in the chemistry of recent Axial Seamount eruptives, whereas CoAxial lavas exhibit distinct chemical differences over short time periods. Significant chemical differences observed among depleted CoAxial lavas emplaced close to one another in space and time are in marked contrast to the relatively constant chemical characteristics of enriched lavas erupted at the magmatically more robust Axial segment only 10's of kilometers to the south and west. New trace element and isotopic (Sr, Nd, Pb) geochemical analyses of historic and older CoAxial lavas have resulted in better documentation of interflow and intraflow chemical variation providing an improved understanding of spatial/temporal chemical variability in lavas, and further insight into JdFR magmatic processes. Modeling of major and trace element abundances suggest that the observed intraflow chemical variation within CoAxial lavas is largely due to shallow-level fractional crystallization but that a single fractional crystallization model cannot account for all interflow chemical variation. In fact, elemental and isotopic data require different parental magmas for each of the three recent CoAxial Segment lava flows suggesting very short-term differences or changes in the chemical character of the mantle source region. In particular

75 FR 8036 - Monitor-Hot Creek Rangeland Project

Science.gov (United States)

2010-02-23

... DEPARTMENT OF AGRICULTURE Forest Service Monitor-Hot Creek Rangeland Project AGENCY: Forest... Rangeland Project area. The analysis will determine if a change in management direction for livestock grazing is needed to move existing resource conditions within the Monitor-Hot Creek Rangeland Project area...

Modelled transport and deposition of sulphur over Southern Africa

CSIR Research Space (South Africa)

Zunckel, M

2000-01-01

Full Text Available Ambient SO2 concentrations and atmospheric deposition of sulphur resulting from emissions on the industrialised highveld region of South Africa are estimated using the multi-scale atmospheric transport and chemistry (MATCH) modelling system...

A baseline and watershed assessment in the Lynx Creek, Brenot Creek, and Portage Creek watersheds near Hudson's Hope, BC : summary report

International Nuclear Information System (INIS)

Matscha, G.; Sutherland, D.

2005-06-01

This report summarized a baseline monitoring program for the Lynx Creek, Brenot Creek, and Portage Creek watersheds located near Hudson's Hope, British Columbia (BC). The monitoring program was designed to more accurately determine the effects of potential coalbed gas developments in the region, as well as to assess levels of agricultural and forest harvesting, and the impacts of current land use activities on water quantity and quality. Water quality was sampled at 18 sites during 5 different flow regimes, including summer and fall low flows; ice cover; spring run-off; and high flows after a heavy summer rain event. Sample sites were located up and downstream of both forest and agricultural activities. The water samples were analyzed for 70 contaminants including ions, nutrients, metals, hydrocarbons, and hydrocarbon fractions. Results showed that while many analyzed parameters met current BC water quality guidelines, total organic carbon, manganese, cadmium, E. coli, fecal coliforms, and fecal streptococci often exceeded recommended guidelines. Aluminum and cobalt values exceeded drinking water guidelines. The samples also had a slightly alkaline pH and showed high conductance. A multiple barrier approach was recommended to reduce potential risks of contamination from the watersheds. It was concluded that a more refined bacteria source tracking method is needed to determine whether fecal pollution has emanated from human, livestock or wildlife sources. 1 tab., 9 figs

Wolf Creek Generating Station containment model

International Nuclear Information System (INIS)

Nguyen, D.H.; Neises, G.J.; Howard, M.L.

1995-01-01

This paper presents a CONTEMPT-LT/28 containment model that has been developed by Wolf Creek Nuclear Operating Corporation (WCNOC) to predict containment pressure and temperature behavior during the postulated events at Wolf Creek Generating Station (WCGS). The model has been validated using data provided in the WCGS Updated Safety Analysis Report (USAR). CONTEMPT-LT/28 model has been used extensively at WCGS to support plant operations, and recently, to support its 4.5% thermal power uprate project

Structural and temporal requirements for geomagnetic field reversal deduced from lava flows.

Science.gov (United States)

Singer, Brad S; Hoffman, Kenneth A; Coe, Robert S; Brown, Laurie L; Jicha, Brian R; Pringle, Malcolm S; Chauvin, Annick

2005-03-31

Reversals of the Earth's magnetic field reflect changes in the geodynamo--flow within the outer core--that generates the field. Constraining core processes or mantle properties that induce or modulate reversals requires knowing the timing and morphology of field changes that precede and accompany these reversals. But the short duration of transitional field states and fragmentary nature of even the best palaeomagnetic records make it difficult to provide a timeline for the reversal process. 40Ar/39Ar dating of lavas on Tahiti, long thought to record the primary part of the most recent 'Matuyama-Brunhes' reversal, gives an age of 795 +/- 7 kyr, indistinguishable from that of lavas in Chile and La Palma that record a transition in the Earth's magnetic field, but older than the accepted age for the reversal. Only the 'transitional' lavas on Maui and one from La Palma (dated at 776 +/- 2 kyr), agree with the astronomical age for the reversal. Here we propose that the older lavas record the onset of a geodynamo process, which only on occasion would result in polarity change. This initial instability, associated with the first of two decreases in field intensity, began approximately 18 kyr before the actual polarity switch. These data support the claim that complete reversals require a significant period for magnetic flux to escape from the solid inner core and sufficiently weaken its stabilizing effect.

A mangrove creek restoration plan utilizing hydraulic modeling.

Science.gov (United States)

Marois, Darryl E; Mitsch, William J

2017-11-01

Despite the valuable ecosystem services provided by mangrove ecosystems they remain threatened around the globe. Urban development has been a primary cause for mangrove destruction and deterioration in south Florida USA for the last several decades. As a result, the restoration of mangrove forests has become an important topic of research. Using field sampling and remote-sensing we assessed the past and present hydrologic conditions of a mangrove creek and its connected mangrove forest and brackish marsh systems located on the coast of Naples Bay in southwest Florida. We concluded that the hydrology of these connected systems had been significantly altered from its natural state due to urban development. We propose here a mangrove creek restoration plan that would extend the existing creek channel 1.1 km inland through the adjacent mangrove forest and up to an adjacent brackish marsh. We then tested the hydrologic implications using a hydraulic model of the mangrove creek calibrated with tidal data from Naples Bay and water levels measured within the creek. The calibrated model was then used to simulate the resulting hydrology of our proposed restoration plan. Simulation results showed that the proposed creek extension would restore a twice-daily flooding regime to a majority of the adjacent mangrove forest and that there would still be minimal tidal influence on the brackish marsh area, keeping its salinity at an acceptable level. This study demonstrates the utility of combining field data and hydraulic modeling to aid in the design of mangrove restoration plans.

Surface-water resources of Polecat Creek basin, Oklahoma

Science.gov (United States)

Laine, L.L.

1956-01-01

A compilation of basic data on surface waters in Polecat Creek basin is presented on a monthly basis for Heyburn Reservoir and for Polecat Creek at Heyburn, Okla. Chemical analyses are shown for five sites in the basin. Correlation of runoff records with those for nearby basins indicates that the average annual runoff of the basin above gaging station at Heyburn is 325 acre-feet per square mile. Estimated duration curves of daily flow indicate that under natural conditions there would be no flow in Polecat Creek at Heyburn (drainage area, 129 square miles) about 16 percent of the time on an average, and that the flow would be less than 3 cubic feet per second half of the time. As there is no significant base flow in the basin, comparable low flows during dry-weather periods may be expected in other parts of the basin. During drought periods Heyburn Reservoir does not sustain a dependable low-water flow in Polecat Creek. Except for possible re-use of the small sewage effluent from city of Sapulpa, dependable supplies for additional water needs on the main stem will require development of supplemental storage. There has been no regular program for collection of chemical quality data in the basin, but miscellaneous analyses indicate a water of suitable quality for municipal and agricultural uses in Heyburn Reservoir and Polecat Creek near Heyburn. One recent chemical analysis indicates the possibility of a salt pollution problem in the Creek near Sapulpa. (available as photostat copy only)

Electron capture detection of sulphur gases in carbon dioxide at the parts-per-billion level

International Nuclear Information System (INIS)

Pick, M.E.

1979-01-01

A gas chromatograph with an electron capture detector has been used to determine sulphur gases in CO 2 at the parts-per-billion level, with particular application to the analysis of coolant from CO 2 cooled nuclear reactors. For COS, CS 2 , CH 3 SH, H 2 S and (CH 3 ) 2 S 2 the detector has a sensitivity comparable with the more commonly used flame photometric detector, but it is much less sensitive towards (CH 3 ) 2 S and thiophene. In addition, the paper describes a simple method for trapping sulphur gases which might enable detection of sub parts-per-billion levels of sulphur compounds. (Auth.)

Sulphur oxidising bacteria in mangrove ecosystem: A review

African Journals Online (AJOL)

SAM

2014-07-16

Jul 16, 2014 ... factors such as salinity and nutrient availability highly variable. Mangrove .... sulphate and converts it into organic sulphur compound. (Subba Rao ..... of organic fertilizer long favored in Australia. .... Fish. Technol. Soc. 21:126-130. Dias ACF, Andreote FD, Rigonato J, Fiore MF, Melo IS, Araujo WL. (2010).

The role of unsteady effusion rates on inflation in long-lived lava flow fields

Science.gov (United States)

Rader, E.; Vanderkluysen, L.; Clarke, A.

2017-11-01

The emission of volcanic gases and particles can have global and lasting environmental effects, but their timing, tempo, and duration can be problematic to quantify for ancient eruptions where real-time measurements are absent. Lava flows, for example, may be long-lasting, and their impact is controlled by the rate, tempo, and vigor of effusion. These factors are currently difficult to derive from the geologic record but can have large implications for the atmospheric impact of an eruption. We conducted a set of analogue experiments on lava flow inflation aiming at connecting lava morphologies preserved in the rock record to eruption tempo and dynamics through pulsating effusion rates. Inflation, a process where molten material is injected beneath the crust of an active lava flow and lifts it upwards, is a common phenomenon in basaltic volcanic systems. This mechanism requires three components: a) a coherent, insulating crust; b) a wide-spread molten core; and c) pressure built up beneath the crust from a sustained supply of molten material. Inflation can result in a lava flow growing tens of meters thick, even in flow fields that expand hundreds of square kilometers. It has been documented that rapid effusion rates tend to create channels and tubes, isolating the active part of the flow from the stagnant part, while slow effusion rates may cause crust to form quickly and seize up, forcing lava to overtop the crust. However, the conditions that allow for inflation of large flow fields have not previously been evaluated in terms of effusion rate. By using PEG 600 wax and a programmable pump, we observe how, by pulsating effusion rate, inflation occurs even in very low viscosity basaltic eruptions. We show that observations from inflating Hawaiian lava flows correlate well with experimental data and indicate that instantaneous effusion rates may have been 3 times higher than average effusion rates during the emplacement of the 23 January 1988 flow at Kīlauea (Hawai

Geohydrology of the stratified-drift aquifer system in the lower Sixmile Creek and Willseyville Creek trough, Tompkins County, New York

Science.gov (United States)

Miller, Todd S.; Karig, Daniel E.

2010-01-01

In 2002, the U.S. Geological Survey, in cooperation with the Tompkins County Planning Department began a series of studies of the stratified-drift aquifers in Tompkins County to provide geohydrologic data for planners to develop a strategy to manage and protect their water resources. This aquifer study in lower Sixmile Creek and Willseyville Creek trough is the second in a series of aquifer studies in Tompkins County. The study area is within the northern area of the Appalachian Plateau and extends about 9 miles from the boundary between Tompkins County and Tioga County in the south to just south of the City of Ithaca in the north. In lower Sixmile Creek and Willseyville Creek trough, confined sand and gravel aquifers comprise the major water-bearing units while less extensive unconfined units form minor aquifers. About 600 people who live in lower Sixmile Creek and Willseyville Creek trough rely on groundwater from the stratified-drift aquifer system. In addition, water is used by non-permanent residents such as staff at commercial facilities. The estimated total groundwater withdrawn for domestic use is about 45,000 gallons per day (gal/d) or 0.07 cubic foot per second (ft3/s) based on an average water use of 75 gal/d per person for self-supplied water systems in New York. Scouring of bedrock in the preglacial lower Sixmile Creek and Willseyville Creek valleys by glaciers and subglacial meltwaters truncated hillside spurs, formed U-shaped, transverse valley profiles, smoothed valley walls, and deepened the valleys by as much as 300 feet (ft), forming a continuous trough. The unconsolidated deposits in the study area consist mostly of glacial drift, both unstratified drift (till) and stratified drift (laminated lake, deltaic, and glaciofluvial sediments), as well as some post-glacial stratified sediments (lake-bottom sediments that were deposited in reservoirs, peat and muck that were deposited in wetlands, and alluvium deposited by streams). Multiple advances and

Recent Development of Carbonaceous Materials for Lithium–Sulphur Batteries

Directory of Open Access Journals (Sweden)

Xingxing Gu

2016-11-01

Full Text Available The effects of climate change are just beginning to be felt, and as such, society must work towards strategies of reducing humanity’s impact on the environment. Due to the fact that energy production is one of the primary contributors to greenhouse gas emissions, it is obvious that more environmentally friendly sources of power are required. Technologies such as solar and wind power are constantly being improved through research; however, as these technologies are often sporadic in their power generation, efforts must be made to establish ways to store this sustainable energy when conditions for generation are not ideal. Battery storage is one possible supplement to these renewable energy technologies; however, as current Li-ion technology is reaching its theoretical capacity, new battery technology must be investigated. Lithium–sulphur (Li–S batteries are receiving much attention as a potential replacement for Li-ion batteries due to their superior capacity, and also their abundant and environmentally benign active materials. In the spirit of environmental harm minimization, efforts have been made to use sustainable carbonaceous materials for applications as carbon–sulphur (C–S composite cathodes, carbon interlayers, and carbon-modified separators. This work reports on the various applications of carbonaceous materials applied to Li–S batteries, and provides perspectives for the future development of Li–S batteries with the aim of preparing a high energy density, environmentally friendly, and sustainable sulphur-based cathode with long cycle life.

Sulphur mustard degradation on zirconium doped Ti-Fe oxides

Energy Technology Data Exchange (ETDEWEB)

Stengl, Vaclav, E-mail: stengl@iic.cas.cz [Department of Solid State Chemistry, Institute of Inorganic Chemistry AS CR v.v.i 250 68 Husinec-Rez (Czech Republic); Grygar, Tomas Matys [Department of Solid State Chemistry, Institute of Inorganic Chemistry AS CR v.v.i 250 68 Husinec-Rez (Czech Republic); Oplustil, Frantisek; Nemec, Tomas [Military Technical Institute of Protection Brno Veslarska 230, 628 00 Brno (Czech Republic)

2011-09-15

Highlights: {yields} New stechiometric materials for sulphur mustard degradation. {yields} High degree of degradation, more then 95% h{sup -1}. {yields} One-pot synthesis procedure. - Abstract: Zirconium doped mixed nanodispersive oxides of Ti and Fe were prepared by homogeneous hydrolysis of sulphate salts with urea in aqueous solutions. Synthesized nanodispersive metal oxide hydroxides were characterised as the Brunauer-Emmett-Teller (BET) surface area and Barrett-Joiner-Halenda porosity (BJH), X-ray diffraction (XRD), infrared (IR) spectroscopy, scanning electron microscopy (SEM) with energy-dispersive X-ray (EDX) microanalysis, and acid-base titration. These oxides were taken for an experimental evaluation of their reactivity with sulphur mustard (chemical warfare agent HD or bis(2-chloroethyl)sulphide). The presence of Zr{sup 4+} dopant tends to increase both the surface area and the surface hydroxylation of the resulting doped oxides in such a manner that it can contribute to enabling the substrate adsorption at the oxide surface and thus accelerate the rate of degradation of warfare agents. The addition of Zr{sup 4+} to the hydrolysis of ferric sulphate with urea shifts the reaction route and promotes formation of goethite at the expense of ferrihydrite. We discovered that Zr{sup 4+} doped oxo-hydroxides of Ti and Fe exhibit a higher degradation activity towards sulphur mustard than any other yet reported reactive sorbents. The reaction rate constant of the slower parallel reaction of the most efficient reactive sorbents is increased with the increasing amount of surface base sites.

Two stage fluid bed-plasma gasification process for solid waste valorisation: Technical review and preliminary thermodynamic modelling of sulphur emissions

International Nuclear Information System (INIS)

Morrin, Shane; Lettieri, Paola; Chapman, Chris; Mazzei, Luca

2012-01-01

Highlights: ► We investigate sulphur during MSW gasification within a fluid bed-plasma process. ► We review the literature on the feed, sulphur and process principles therein. ► The need for research in this area was identified. ► We perform thermodynamic modelling of the fluid bed stage. ► Initial findings indicate the prominence of solid phase sulphur. - Abstract: Gasification of solid waste for energy has significant potential given an abundant feed supply and strong policy drivers. Nonetheless, significant ambiguities in the knowledge base are apparent. Consequently this study investigates sulphur mechanisms within a novel two stage fluid bed-plasma gasification process. This paper includes a detailed review of gasification and plasma fundamentals in relation to the specific process, along with insight on MSW based feedstock properties and sulphur pollutant therein. As a first step to understanding sulphur partitioning and speciation within the process, thermodynamic modelling of the fluid bed stage has been performed. Preliminary findings, supported by plant experience, indicate the prominence of solid phase sulphur species (as opposed to H 2 S) – Na and K based species in particular. Work is underway to further investigate and validate this.

Evidence for contamination of recent Hawaiian lavas from 230Th-238U data

International Nuclear Information System (INIS)

Condomines, M.; Bernat, M.; Allegre, C.J.

1976-01-01

230 Th- 238 U radioactive disequilibrium was studied in the historical lava flows of the Mauna Loa and Kilauea, Hawaii. Large variations of the ( 230 Th/ 232 Th) ratio among lavas of the same volcano that were erupted at a few years' interval are interpreted as due to contamination. The contamination probably occurs by assimilation of zeolitic minerals formed by seawater interaction while the magma resides in a superficial chamber. (Auth.)

Volatile sulphur compounds in morning breath of human volunteers.

NARCIS (Netherlands)

Snel, J.; Burgering, M.; Smit, B.; Noordman, W.; Tangerman, A.; Winkel, E.G.; Kleerebezem, M.

2011-01-01

OBJECTIVE: morning breath contains elevated concentrations of volatile sulphur components (VSCs). Therefore, morning breath is recognised as a surrogate target for interventions on breath quality. Nevertheless, factors influencing morning breath are poorly understood. Our aim was to evaluate

Volatile sulphur compounds in morning breath of human volunteers

NARCIS (Netherlands)

Snel, Johannes; Burgering, Maurits; Smit, Bart; Noordman, Wouter; Tangerman, Albert; Winkel, Edwin G.; Kleerebezem, Michiel

Objective: Morning breath contains elevated concentrations of volatile sulphur components (VSCs). Therefore, morning breath is recognised as a surrogate target for interventions on breath quality. Nevertheless, factors influencing morning breath are poorly understood. Our aim was to evaluate

Emplacement of Xenolith Nodules in the Kaupulehu Lava Flow, Hualalai Volcano, Hawaii

Science.gov (United States)

Guest, J. E.; Spudis, P. D.; Greeley, R.; Taylor, G. J.; Baloga, S. M.

1995-01-01

The basaltic Kaupulehu 1800-1801 lava flow of Hualalai Volcano, Hawaii contains abundant ultramafic xenoliths. Many of these xenoliths occur as bedded layers of semi-rounded nodules, each thinly coated with a veneer (typically 1 mm thick) of lava. The nodule beds are analogous to cobble deposits of fluvial sedimentary systems. Although several mechanisms have been proposed for the formation of the nodule beds, it was found that, at more than one locality, the nodule beds are overbank levee deposits. The geological occurrence of the nodules, certain diagnostic aspects of the flow morphology and consideration of the inferred emplacement process indicate that the Kaupulehu flow had an exceptionally low viscosity on eruption and that the flow of the lava stream was extremely rapid, with flow velocities of at least 10 m/s (more than 40 km/h. This flow is the youngest on Hualalai Volcano and future eruptions of a similar type would pose considerable hazard to life as well as property.

Disclosing the temperature of columnar jointing in lavas.

Science.gov (United States)

Lamur, Anthony; Lavallée, Yan; Iddon, Fiona E; Hornby, Adrian J; Kendrick, Jackie E; von Aulock, Felix W; Wadsworth, Fabian B

2018-04-12

Columnar joints form by cracking during cooling-induced contraction of lava, allowing hydrothermal fluid circulation. A lack of direct observations of their formation has led to ambiguity about the temperature window of jointing and its impact on fluid flow. Here we develop a novel thermo-mechanical experiment to disclose the temperature of columnar jointing in lavas. Using basalts from Eyjafjallajökull volcano (Iceland) we show that contraction during cooling induces stress build-up below the solidus temperature (980 °C), resulting in localised macroscopic failure between 890 and 840 °C. This temperature window for incipient columnar jointing is supported by modelling informed by mechanical testing and thermal expansivity measurements. We demonstrate that columnar jointing takes place well within the solid state of volcanic rocks, and is followed by a nonlinear increase in system permeability of <9 orders of magnitude during cooling. Columnar jointing may promote advective cooling in magmatic-hydrothermal environments and fluid loss during geothermal drilling and thermal stimulation.

Sulphur mountain: Cosmic ray intensity records

International Nuclear Information System (INIS)

Venkatesan, D.; Mathews, T.

1985-01-01

This book deals with the comic ray intensity registrations at the Sulphur Mountain Cosmic Ray Laboratory. The time series of intensity form a valuable data-set, for studying cosmic ray intensity variations and their dependence on solar activity. The IGY neutron monitor started operating from July 1, 1957 and continued through 1963. Daily mean values are tabulated for the period and these are also represented in plots. This monitor was set up by the National Research Council of Canada

Di- or polysulphide-bound biomarkers in sulphur-rich geomacromolecules as revealed by selective chemolysis

Science.gov (United States)

Kohnen, Math E. l.; Sinninghe Damsté, Jaap S.; Kock-van Dalen, A. c.; Jan, W. De Leeuw

1991-05-01

Three types of sulphur-rich high-molecular-weight material in the alkylsulphide, the polar, and the asphaltene fractions isolated from the bitumen of an immature bituminous shale from the Vena del Gesso basin (Italy) were desulphurised using Raney Ni and were treated with MeLi/MeI, a chemical degradation method which cleaves selectively and quantitatively di- or polysulphide linkages. The products formed were characterised by gas chromatography-mass spectrometry. Raney Ni desulphurisation revealed that these S-rich macromolecules are in substantial part composed of sulphur-linked biomarkers with linear, branched, isoprenoid, steroid, hopanoid, and carotenoid carbon skeletons. MeLi/Mel treatment provided evidence that a major part of the total amount of macromolecularly bound biomarkers are linked via di- or polysulphide moieties to the macromolecular network. Since the di- or polysulphide linkages are attached at specific positions of the bound biomarkers it is proposed that they are formed by intermolecular incorporation reactions of HS x- into low-molecular-weight functionalised biological lipids during early diagenesis. The different properties (solubility and molecular weight) of the sulphur-rich macromolecules in the alkylsulphide, the resin, and the asphaltene fractions can be explained simply by differences in degree of sulphur cross-linking.

Geohydrology and water quality of the stratified-drift aquifers in Upper Buttermilk Creek and Danby Creek Valleys, Town of Danby, Tompkins County, New York

Science.gov (United States)

Miller, Todd S.

2015-11-20

In 2006, the U.S. Geological Survey, in cooperation with the Town of Danby and the Tompkins County Planning Department, began a study of the stratified-drift aquifers in the upper Buttermilk Creek and Danby Creek valleys in the Town of Danby, Tompkins County, New York. In the northern part of the north-draining upper Buttermilk Creek valley, there is only one sand and gravel aquifer, a confined basal unit that overlies bedrock. In the southern part of upper Buttermilk Creek valley, there are as many as four sand and gravel aquifers, two are unconfined and two are confined. In the south-draining Danby Creek valley, there is an unconfined aquifer consisting of outwash and kame sand and gravel (deposited by glacial meltwaters during the late Pleistocene Epoch) and alluvial silt, sand, and gravel (deposited by streams during the Holocene Epoch). In addition, throughout the study area, there are several small local unconfined aquifers where large tributaries deposited alluvial fans in the valley.

Terrestrial Lava Lake Physical Parameter Estimation Using a Silicate Cooling Model - Implications for a Return to the Volcanic Moon, Io

Science.gov (United States)

Davies, Ashley

2010-05-01

Active lava lakes are open volcanic systems, where lava circulates between a magma chamber and the surface. Rare on Earth, lava lakes may be common on Io, the highly volcanic moon of Jupiter (see [1]). Lava lakes are important targets for future missions to Io [2, 3] as they provide excellent targets at which to measure lava eruption temperature (see [2] for other targets). With this in mind, hand-held infrared imagers were used to collect in-situ thermal emission data from the anorthoclase phonolite lava lake at Erebus volcano (Antarctica) in December 2005 [1, 3] and the basalt lava lake at Erta'Ale volcano (Ethiopia) in September 2009. These data have been analysed to establish surface temperature and area distributions and the integrated thermal emission spectra for each lava lake. These spectra have been used to test models developed for analysis of remote sensing data of lava lakes and lava flows on both Earth and Io, where no ground-truth exists. The silicate cooling model [4] assumes, for the lava lake model variant, that the existing surface crust has been created at a fixed rate. Model output consists of a synthesized thermal emission spectrum, estimate of surface age range, and a rate of surface crust area formation. The cooling model provides accurate reproductions of actual thermal spectra and the total emitting area to within a few percent of actual emitting area. Despite different composition lavas, the integrated thermal emission spectra from the two terrestrial lava lakes studied are very similar in shape, and, importantly, bear a striking similarity to spectra of Pele, a feature on Io that has been proposed to be a persistent, active lava lake [1]. The 2005 Erebus lava lake had an area of ~820 m2 and a measured surface temperature distribution of 1090 K to 575 K with a broad peak from 730 K to 850 K [5]. Total heat loss was estimated to be 23.5 MW [5]. The model fit yielded an area of ~820 m2, temperatures from 1475 K to 699 K, and an average

Optimisation of Dilute Sulphuric Acid Hydrolysis of Waste ...

African Journals Online (AJOL)

Dilute sulphuric acid hydrolysis of waste paper was investigated in this study. The effects of acid concentration, time, temperature and liquid to solid ratio on the total reducing sugar concentration were studied over three levels using a four variable Box-Behnken design (BBD). A statistical model was developed for the ...

Effect of soil moisture on sulphur accumulation in overground plant organs and their harm in emmission conditions

Energy Technology Data Exchange (ETDEWEB)

Navara, J; Horvath, I; Hauskrecht, I

1972-01-01

The effect of different soil moisture on sulphur accumulation in the overground organs of Fagopyrum esculentum, moench in immission conditions is dealt with in this paper. The results obtained have shown that even under equal soil conditions, equal nutrient supply and age evenness of the analyzed material the total sulphur content of leaves grown in immission conditions (sulphur oxides, hydrogen sulphide, carbon disulphide, etc.) at equal soil moisture was essentially higher when compared with unirrigated plants and corresponded also to the degree of harm and crop reduction of the experimental plants. Therefore it is necessary when utilizing sulphur content of indicating plants, which serves for a large-area diagnosis of vegetation harm with immissions, to take into consideration, in addition to other factors (soil, nutrition, age of plants), the soil moisture as well.

Physico-chemical conversion of sulphur dioxide in a power plant plume

International Nuclear Information System (INIS)

Lewin, E.E.

1978-03-01

A review is given of the actual knowledge of SO 2 atmospheric processes gained from laboratory and field experiments. Implementation is described of the instrumentation, operational procedures and analytical methods in connection with a field study of the conversion and dispersion of SO 2 in an oil-fired power plant plume. Furthermore, the preliminary results are included of five experiments performed until the end of 1976. Measurements were performed from an aircraft and included continuous registration of NOsub(x), SO 2 , SF 6 , and particle concentrations, as well as temperature and humidity. It was planned to label sulphur from the source in question with sulphur-35. However, this part of the experiment had to be abandoned because of public opinion on the use of radioactive tracers. Sulphur hexafluoride was used as an internal tracer for the plume. A half-life for SO 2 of about 30 min was determined from one of the experiments. In this connection the possibility of using NOsub(x) as a conservative tracer is shown. Possible ways of removal are discussed and the rate of two of the processes is calculated by means of a model describing the chemical conversion in a dispersing plume. (author)

A novel technology for measuring the eruption temperature of silicate lavas with remote sensing: Application to Io and other planets

Science.gov (United States)

Davies, Ashley Gerard; Gunapala, Sarath; Soibel, Alexander; Ting, David; Rafol, Sir; Blackwell, Megan; Hayne, Paul O.; Kelly, Michael

2017-09-01

The highly variable and unpredictable magnitude of thermal emission from evolving volcanic eruptions creates saturation problems for remote sensing instruments observing eruptions on Earth and on Io, the highly volcanic moon of Jupiter. For Io, it is desirable to determine the temperature of the erupting lavas as this measurement constrains lava composition. One method of determining lava eruption temperature is by measuring radiant flux at two or more wavelengths and fitting a blackbody thermal emission function. Only certain styles of volcanic activity are suitable, those where detectable thermal emission is from a restricted range of surface temperatures close to the eruption temperature. Volcanic processes where this occurs include large lava fountains; smaller lava fountains common in active lava lakes; and lava tube skylights. Problems that must be overcome to obtain usable data are: (1) the rapid cooling of the lava between data acquisitions at different wavelengths, (2) the unknown magnitude of thermal emission, which has often led to detector saturation, and (3) thermal emission changing on a shorter timescale than the observation integration time. We can overcome these problems by using the HOT-BIRD detector and a novel, advanced digital readout circuit (D-ROIC) to achieve a wide dynamic range sufficient to image lava on Io without saturating. We have created an instrument model that allows various instrument parameters (including mirror diameter, number of signal splits, exposure duration, filter band pass, and optics transmissivity) to be tested to determine the detectability of thermal sources on Io's surface. We find that a short-wavelength infrared instrument on an Io flyby mission can achieve simultaneity of observations by splitting the incoming signal for all relevant eruption processes and still obtain data fast enough to remove uncertainties in accurate determination of the highest lava surface temperatures. Observations at 1 and 1.5 μm are

76 FR 65118 - Drawbridge Operation Regulation; Bear Creek, Sparrows Point, MD

Science.gov (United States)

2011-10-20

...-AA09 Drawbridge Operation Regulation; Bear Creek, Sparrows Point, MD AGENCY: Coast Guard, DHS. ACTION... regulation. The Baltimore County Revenue Authority (Dundalk Avenue) highway toll drawbridge across Bear Creek... applicable or necessary. Basis and Purpose The drawbridge across Bear Creek, mile 1.5 was removed and...

Evaluation of the protein concentration in enzymes via the determination of sulphur by TXRF

International Nuclear Information System (INIS)

Mertens, M.; Rittmeyer, C.; Kolbesen, B.O.

2000-01-01

Total reflection x-ray fluorescence spectrometry (TXRF) offers many advantages for the identification of trace elements in biological samples like enzymes, tissues or plants. Without any preliminary treatment elements may be determined with high accuracy especially transition metals like Fe, Ni, Cu, Mo and the alkaline earth metal Ca. A further aspect of the investigation of enzymes is the simple and simultaneous determination of light elements. Especially sulphur is of interest. The element sulphur exists mainly in the two amino, acids methionine and cysteine as well as in iron-sulphur clusters and may be used for an easy and simultaneous calculation of the protein concentration. Hence the quantitative determination of sulphur by TXRF allows a cross-check regarding of the conventional quantitative determination of protein concentration by, for example, the Lowry method. On the basis of three enzymes of different origins and molecular weights the presentation will show the influence of the bio-organic matrix and different buffer media on element determination by TXRF. As is already known the influence of the matrix on the detection of light elements is stronger than on transition metals. It can be discussed whether layer thickness and layer effects of the drying residues (characterization by SEM and thickness profilometer (ALPHA-step)) and / or self absorption effects as well as the excitation are of significance. The results indicate that with enzymes of low molecular weight a reliable determination of sulphur is possible whereas those with higher molecular weights gave poorer results on account of the matrix effects described. (author)

Crystal-rich lava dome extrusion during vesiculation: An experimental study

Science.gov (United States)

Pistone, Mattia; Whittington, Alan G.; Andrews, Benjamin J.; Cottrell, Elizabeth

2017-11-01

Lava dome-forming eruptions represent a common eruptive style and a major hazard at numerous active volcanoes worldwide. The extrusion mechanics of crystal-rich lava domes and the influence of volatiles on the transition from viscous to brittle behaviour during lava dome extrusion remain unclear. Understanding how gas exsolution and crystallinity control effusive versus explosive eruption behaviour is essential. Here, we present new experimental results on the rheology of synthesised, crystal-rich (50 to 80 vol% quartz crystals), hydrous (4.2 wt% H2O in the glass) dacite samples, which vesiculate from 5 to 27 vol% gas bubbles at high temperatures (from glass transition temperature to 797 °C) during deformation conducted in a parallel plate viscometer (constant stress at 0.63-0.64 MPa, and variable strain-rates ranging from 8.32·10- 8 to 3.58·10- 5 s- 1). The experiments reproduce certain aspects of lava dome deformation in volcanic conduits during vesiculation of the residual melt, instigated in the experiments by increasing temperature. During gas exsolution (i.e. nucleation and growth of gas-pressurised bubbles) and volume inflation, we find that the rheological lubrication of the system during deformation is strongly dictated by the initial crystallinity. At crystal contents < 60 vol%, gas bubbles form and coalesce during expansion and viscous deformation, favouring strain localisation and gas permeability within shear bands, which control the overall sample rheology. At crystallinities of 60 to 70 vol%, gas exsolution generates pressurisation (i.e. pore pressure increase) within the bubbles trapped in the solid crystal clusters, and embryonic formation of microscopic fractures through melt and crystals drives the system to a brittle behaviour. At higher crystallinity (80 vol%) vesiculation leads to large pressurisation, which then triggers extensive brittle fragmentation. Through macroscopic fractures, outgassing determines the rheological stalling of the

Performance evaluation of high-sulphur coal-fired USC plant integrated with SNOX and CO2 capture sections

International Nuclear Information System (INIS)

Cau, Giorgio; Tola, Vittorio; Bassano, Claudia

2015-01-01

In recent years coal-fired power plants have increased their role in the global energy scenario thanks to reliability, security of fuel supply and lower cost of fuel and electricity. In this framework global warming issues require a sustainable use of coal and great efforts for greenhouse gases reduction, addressing research and development projects towards more efficient solutions in terms of efficiency and environmental impact. With this aim in this paper a performance assessment of an Ultra Super Critical (USC) steam plant integrated with a CO 2 removal section was carried out. The study is based on simulation models specifically developed through Aspen-Plus and Gate-Cycle software platforms. Performance was assessed referring to typical USC commercial size plants (400–600 MW), fuelled by a mix of a low-sulphur coal and a Sardinian (Sulcis) high-sulphur coal. The USC plant, based on a reheated and regenerative Rankine cycle, is integrated with an SNOX section, with integrated DeNO x and DeSO x processes, and a low temperature CO 2 capture section. The SNOX technology shows several advantages in comparison to conventional de-nitrification and de-sulphuration systems. In particular it is capable to remove both nitrogen and sulphur oxides, requiring less energy absorption compared to traditional FGD systems, allowing a further preheating of the combustion air and without producing process waste. Besides the SNOX releases a commercial product as the sulphuric acid (H 2 SO 4 ) and operational costs are reduced when sulphur content in the coal increases. The CO 2 capture system was based on a chemical absorption process. A conventional system based on an amine (monoethanolamine, MEA) aqueous solution was considered. In order to match high pressure and purity CO 2 transportation requirements, the CO 2 removal section is also integrated with a conditioning and compression section. A performance assessment of the USC plant was carried out varying the high-sulphur coal

Incisional Colopexy for Treatment of Chronic, Recurrent Colocloacal Prolapse in a Sulphur-Crested Cockatoo (Cacatua galerita)

NARCIS (Netherlands)

van Zeeland, Yvonne; Schoemaker, Nico; van Sluijs, Freek

2014-01-01

Objective To report a surgical technique for treatment of chronic, recurrent cloacal prolapse in a sulphur-crested cockatoo (Cacatua galerita). Study Design Clinical report Animals Sulphur-crested cockatoo (n = 1) Methods The bird was admitted with a 2-year history of periodic lethargy, decreased

Johnson Creek Artificial Propagation and Enhancement Project Operations and Maintenance Program; Brood Year 1998: Johnson Creek Chinook Salmon Supplementation, Biennial Report 1998-2000.

Energy Technology Data Exchange (ETDEWEB)

Daniel, Mitch; Gebhards, John

2003-05-01

The Nez Perce Tribe, through funding provided by the Bonneville Power Administration, has implemented a small scale chinook salmon supplementation program on Johnson Creek, a tributary in the South Fork of the Salmon River, Idaho. The Johnson Creek Artificial Propagation Enhancement project was established to enhance the number of threatened Snake River summer chinook salmon (Oncorhynchus tshawytscha) returning to Johnson Creek through artificial propagation. Adult chinook salmon collection and spawning began in 1998. A total of 114 fish were collected from Johnson Creek and 54 fish (20 males and 34 females) were retained for Broodstock. All broodstock were transported to Lower Snake River Compensation Plan's South Fork Salmon River adult holding and spawning facility, operated by the Idaho Department of Fish and Game. The remaining 60 fish were released to spawn naturally. An estimated 155,870 eggs from Johnson Creek chinook spawned at the South Fork Salmon River facility were transported to the McCall Fish Hatchery for rearing. Average fecundity for Johnson Creek females was 4,871. Approximately 20,500 eggs from females with high levels of Bacterial Kidney Disease were culled. This, combined with green-egg to eyed-egg survival of 62%, resulted in about 84,000 eyed eggs produced in 1998. Resulting juveniles were reared indoors at the McCall Fish Hatchery in 1999. All of these fish were marked with Coded Wire Tags and Visual Implant Elastomer tags and 8,043 were also PIT tagged. A total of 78,950 smolts were transported from the McCall Fish Hatchery and released directly into Johnson Creek on March 27, 28, 29, and 30, 2000.

Impurity photovoltaic effect in silicon solar cell doped with sulphur: A numerical simulation

International Nuclear Information System (INIS)

Azzouzi, Ghania; Chegaar, Mohamed

2011-01-01

The impurity photovoltaic effect (IPV) has mostly been studied in various semiconductors such as silicon, silicon carbide and GaAs in order to increase infrared absorption and hence cell efficiency. In this work, sulphur is used as the IPV effect impurity incorporated in silicon solar cells. For our simulation we use the numerical device simulator (SCAPS). We calculate the solar cell performances (short circuit current density J sc , open circuit voltage V oc , conversion efficiency η and quantum efficiency QE). We study the influence of light trapping and certain impurity parameters like impurity concentration and position in the gap on the solar cell performances. Simulation results for IPV effect on silicon doped with sulphur show an improvement of the short circuit current and the efficiency for sulphur energy levels located far from the middle of the band gap especially at E c -E t =0.18 eV.

Passivation of chalcopyrite during the leaching with sulphuric acid solution in presence of sodium nitrate

Directory of Open Access Journals (Sweden)

Sokić Miroslav D.

2010-01-01

Full Text Available In this work, the process of the chalcopyrite leaching in sulphuric acid solution was investigated. Sodium nitrate was used as oxidant in the leaching process. Chemical reactions of leaching and their thermodynamic possibilities are predicted based on the calculated Gibbs energies and analysis of E−pH diagrams. The negative values of the Gibbs energy show that all chemical reactions are thermodynamically feasible at atmospheric pressure and in a temperature range 25-90°C. At high electrode potential and low pH values, Cu2+, Fe2+ and Fe3+ ions exist in water solutions. The increase of temperature reduces the probability of Fe3+ ion existence in the system. The chalcopyrite concentrate, enriched in the “Rudnik” flotation plant, with 27.08% Cu, 25.12% Fe, 4.15% Zn and 2.28% Pb was used in the work. XRD and DTA analysis of the concentrate reveals that the sample contains mainly the chalcopyrite with small amount of sphalerite. For the description of the reaction of leaching process the leach residuals, obtained at different conditions, were chosen for XRD, TG/DTA and SEM/EDX analyses. The elemental sulphur and chalcopyrite phases identified in leach residuals confirm our prediction that the elemental sulphur is formed during the leaching process. Accordingly, elemental sulphur is the main product of the reaction, while a minor amount of sulphide sulphur is oxidized to sulphate during the leaching. The sulphur formed during the reaction was precipitated at the particle surfaces, and slowed down the leaching rate in the final stage of leaching process. In the initial stage, the reaction rate was controlled by the surface reaction. The mechanism, latter has been changed into a diffusion controlled one.

Fractal and variability analysis of simulations in ozone level due to oxides of nitrogen and sulphur

Science.gov (United States)

Bhardwaj, Rashmi; Pruthi, Dimple

2017-10-01

Air pollution refers to the release of pollutants into the air. These pollutants are detrimental to human the planet as a whole. Apart from causing respiratory infections and pulmonary disorders, rising levels of Nitrogen Dioxide is worsening ozone pollution. Formation of Ground-level ozone involves nitrogen oxides and volatile gases in the sunlight. Volatile gases are emitted from vehicles primarily. Ozone is harmful gas and its exposure can trigger serious health effects as it damages lung tissues. In order to decrease the level of ozone, level of oxides leading to ozone formation has to be dealt with. This paper deals with the simulations in ozone due to oxides of nitrogen and sulphur. The data from Central Pollution Control Board shows positive correlation for ozone with oxides of sulphur and nitrogen for RK Puram, Delhi in India where high concentration of ozone has been found. The correlation between ozone and sulphur, nitrogen oxides is moderate during summer while weak during winters. Ozone with nitrogen and sulphur dioxide follow persistent behavior as Hurst exponent is between 0.5 and 1. The fractal dimension for Sulphur dioxide is 1.4957 indicating the Brownian motion. The behavior of ozone is unpredictable as index of predictability is close to zero.

Effects of cold stratification, sulphuric acid, submersion in hot and ...

African Journals Online (AJOL)

Effects of cold stratification, sulphuric acid, submersion in hot and tap water pretreatments in the greenhouse and open field conditions on germination of bladder-Senna ( Colutea armena Boiss. and Huet.) seeds.

Efficiency of Syrian and Indian rock phosphates for maize in two soils amended with sulphur

International Nuclear Information System (INIS)

Kanacri, S.

1995-01-01

A greenhouse pot experiment was conducted to evaluate the fertilizer use efficiency of three Syrian rock phosphates in comparison to Mussoorie rock phosphate from India for maize grown in a laterite (ultisol) and an alluvial (entisol) soil amended with sulphur, and using sup 3 sup 2 P-labelled triple superphosphate (TSP). Results showed that application of rock phosphates (RPs) to laterite soil significantly increased the dry matter yields of maize shoots, whereas, in alluvial soil, RPs were not found effective in increasing the yields. Data further indicated that all the three Syrian RPs were equally efficient in increasing dry matter yields in laterite soil and were superior to Mussoorie rock phosphate (MRP). Sulphur added in combination with RPs significantly enhanced the dry matter production as well as 'A' value of alluvial soil. Application of sulphur in conjunction with RPs significantly increased the 'A' value of laterite soil however, sulphur did not contribute to any significant increase in the yields. Syrian RPs were more reactive in soils than Mussoorie RP. (author). 7 refs., 6 tabs

Efficiency of Syrian and Indian rock phosphates for maize in two soils amended with sulphur

International Nuclear Information System (INIS)

Kanacri, Saloi; Bhujbal, B.M.

1993-01-01

A greenhouse pot experiment was conducted to evaluate the fertilizer use efficiency of three Syrian rock phosphates in comparison to Mussoorie rock phosphate from India for maize grown in a laterite (ultisol) and an alluvial (entisol) soil amended with sulphur, and using 32 P-labelled triple superphosphate (TSP). Results showed that application of rock phosphates (RPs) to laterite soil significantly increased the dry matter yields of maize shoots, whereas, in alluvial soil, RPs were not found effective in increasing the yields. Data further indicated that all the three Syrian RPs were equally efficient in increasing dry matter yields in laterite soil and were superior to Mussoorie rock phosphate (MRP). Sulphur added in combination with RPs significantly enhanced the dry matter production as well as 'A'value of alluvial soil. Application of sulphur in conjunction with RPs significantly increased the 'A' value of laterite soil, however, sulphur did not contribute to any significant increase in the yields. Syrian RPs were more reactive in soils than Mussoorie RP. (author). 7 refs., 6 tabs

75 FR 68780 - Cedar Creek Wind Energy, LLC; Notice of Filing

Science.gov (United States)

2010-11-09

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. RC11-1-000] Cedar Creek Wind Energy, LLC; Notice of Filing November 2, 2010. Take notice that on October 27, 2010, Cedar Creek Wind Energy, LLC (Cedar Creek) filed an appeal with the Federal Energy Regulatory Commission (Commission) of...

Big Creek Pit Tags

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The BCPITTAGS database is used to store data from an Oncorhynchus mykiss (steelhead/rainbow trout) population dynamics study in Big Creek, a coastal stream along the...

Hot atom chemistry of sulphur

International Nuclear Information System (INIS)

Todorovski, D. S.; Koleva, D. P.

1982-01-01

An attempt to cover all papers dealing with the hot atom chemistry of sulpphur is made. Publications which: a) only touch the problem, b) contain some data, indirectly connected with sulphur hot atom chemistry, c) deal with 35 S-production from a chloride matrix, are included as well. The author's name and literature source are given in the original language, transcribed, when it is necessary, in latine. A number of primery and secondary documents have been used including Chemical Abstracts, INIS Atomindex, the bibliographies of A. Siuda and J.-P. Adloff for 1973 - 77, etc. (authors)

Hydrology of Bishop Creek, California: An Isotopic Analysis

Science.gov (United States)

Michael L. Space; John W. Hess; Stanley D. Smith

1989-01-01

Five power generation plants along an eleven kilometer stretch divert Bishop Creek water for hydro-electric power. Stream diversion may be adversely affecting the riparian vegetation. Stable isotopic analysis is employed to determine surface water/ground-water interactions along the creek. surface water originates primarily from three headwater lakes. Discharge into...

Lava lake activity at the summit of Kīlauea Volcano in 2016

Science.gov (United States)

Patrick, Matthew R.; Orr, Tim R.; Swanson, Donald A.; Elias, Tamar; Shiro, Brian

2018-04-10

The ongoing summit eruption at Kīlauea Volcano, Hawai‘i, began in March 2008 with the formation of the Overlook crater, within Halema‘uma‘u Crater. As of late 2016, the Overlook crater contained a large, persistently active lava lake (250 × 190 meters). The accessibility of the lake allows frequent direct observations, and a robust geophysical monitoring network closely tracks subtle changes at the summit. These conditions present one of the best opportunities worldwide for understanding persistent lava lake behavior and the geophysical signals associated with open-vent basaltic eruptions. In this report, we provide a descriptive and visual summary of lava lake activity during 2016, a year consisting of continuous lava lake activity. The lake surface was composed of large black crustal plates separated by narrow incandescent spreading zones. The dominant motion of the surface was normally from north to south, but spattering produced transient disruptions to this steady motion. Spattering in the lake was common, consisting of one or more sites on the lake margin. The Overlook crater was continuously modified by the deposition of spatter (often as a thin veneer) on the crater walls, with frequent collapses of this adhered lava into the lake. Larger collapses, involving lithic material from the crater walls, triggered several small explosive events that deposited bombs and lapilli around the Halema‘uma‘u Crater rim, but these did not threaten public areas. The lava lake level varied over several tens of meters, controlled primarily by changes in summit magma reservoir pressure (in part driven by magma supply rates) and secondarily by fluctuations in spattering and gas release from the lake (commonly involving gas pistoning). The lake emitted a persistent gas plume, normally averaging 1,000–8,000 metric tons per day (t/d) of sulfur dioxide (SO2), as well as a constant fallout of small juvenile and lithic particles, including Pele’s hair and tears. The

Lava Fountaining Discharge Regime driven by Slug-to-Churn Flow Transition. (Invited)

Science.gov (United States)

Ripepe, M.; Pioli, L.; Marchetti, E.; Ulivieri, G.

2013-12-01

Lava fountaining episodes at Etna volcano appear characterized by the transition between Strombolian and Hawaiian end-member eruptive styles. There is no evidence for this transition in the seismic (i.e. seismic tremor) signal. However, infrasonic records provide unprecedented evidence on this flow transition. Each eruptive episode is characterized by distinctive common trend in the amplitude, waveform and frequency content of the infrasonic wavefield, which evidences the shift from discrete, and transient, strombolian to sustained, and oscillatory, lava fountain dynamics. Large scale experiments on the dynamics of two-phase flow of basaltic magmas show how the transition between different regimes mainly depends on gas volume flow, which in turn controls pressure distribution within the conduit and also magma vesicularity. In particular, while regular large bubble bursting is associated with slug flow regime, large amplitude and low frequency column oscillations are associated with churn flow. In large pipes, transition from slug to churn flow regime is independent on conduit diameter and it is reached at high superficial gas velocity. Lava fountaining episodes at Etna can be thus interpreted as induced by the transition from the slug (discrete strombolian) to churn flow (sustained lava fountain) regimes that is reflecting an increase in the gas discharge rate. Based on laboratory experiments, we calculate that transition between these two end-member explosive regimes at Etna occurs when gas superficial velocity is 76 m/s for near-the-vent stagnant magma conditions.

Hepatobiliary scintigraphy with 99Tcsup(m)-HIDA and 99Tcsup(m)-sulphur colloid

International Nuclear Information System (INIS)

Pedersen, S.A.; Oster-Jorgensen, E.; Schoubye, J.; Odense Univ.

1980-01-01

The results of a study comparing the ability of 99 Tcsup(m)-sulphur colloid and 99 Tcsup(m)- HIDA to demonstrate circumsribed defects and obstruction of the biliary flow to the intestines are reported. As regards focal liver diseases, colloid scintigraphy (SC) had a nosographic sensitivity and specificity of 0.87 and 0.85, respectively. The corresponding figures for the HIDA scintigraphy were 0.40 and 0.92. Concerning the diagnosis of extrahepatic obstrtuction, sulphur colloid scintigraphy had a nosographic sensitivity and specificity of 0.31 and 0.94. The corresponding figures for HIDA scintigraphy were 0.69 and 0.84. The most frequent cause of false results was pattern of hepatocellular disease in sulphur colloid scans in patients with a longstanding biliary onbstruction. The second most frequent error was due to circumscribed defects in SC as well as in HIDA scans in patients with obstructive diseases and a high value of serum bilirubin. A third source of error was the pattern of an obstruction in HIDA scans in patients with focal diseases. The significance of the star pattern the sulphur colloid scan in patients with obstruction is stressed, as the significance of this pattern not has been evaluated previously. It is concluded that the two different scintigraphic methods are complementary tools in the examination of patients with liver diseases. (orig.) [de

Effect of drought stress and sulphur fertilizer on quantity and quality yield of psyllium (Plantago ovata L. in Baluchestan

Directory of Open Access Journals (Sweden)

M. Mousavi nik

2016-05-01

Full Text Available Management of chemical fertilizers application is very important issues on environment and plant yield especially in arid and-semi arid region. In order to determine the effects of drought stresses and fertilizer levels on quantity and quality yields of psyllium (Plantago ovata L., a study was conducted as split plot based on randomized complete block design with four replications at the Natural Resources and Agriculture Researches Center of Balouchestan, Iran, during growing season of 2009-2010. Treatments included different irrigation regimes (three, five and eight times irrigation during the growing season as main plots and four levels of sulphur fertilizer (0, 75, 150 and 225 kg.ha-1 sulphur as sub plot. The results showed that the irrigation regimes and sulphur fertilizer had significant effects on seed and biological yield of psyllium, so the highest seed and biological yields obtained in eight times irrigation. Also, the maximum of these factors were achieved in 225 kg.ha-1 sulphur. The highest harvest index and 1000- seed weight, No. seed per spike and No. spike per plant were observed in eight times irrigation and 225 kg.ha-1 sulphur. The highest plant height was obtained in eight times irrigation and 225 kg.ha-1 sulphur and the maximum mucilage percentage and proline content were obtained in three times irrigation. The maximum mucilage yield and carbohydrate content were achieved in eight times irrigation. Among sulphur fertilizer, the highest amounts for all factors were achieved in 225 kg.ha-1 sulphur. There was positive and significant correlation between seed yield with spike No. per plant, Seed No. per spike, 1000-Seed, biological yield and mucilage yield.

Impact of sulphurous water politzer inhalation on audiometric parameters in children with otitis media with effusion.

Science.gov (United States)

Mirandola, Prisco; Gobbi, Giuliana; Malinverno, Chiara; Carubbi, Cecilia; Ferné, Filippo M; Artico, Marco; Vitale, Marco; Vaccarezza, Mauro

2013-03-01

The positive effects of spa therapy on ear, nose, and throat pathology are known but robust literature in this field, is still lacking. The aim of this study was to assess through a retrospective analysis, the effects on otitis media with effusion of Politzer endotympanic inhalation of sulphurous waters in children aged 5-9 years. A cohort of 95 patients was treated with Politzer insufflations of sulphurous water: 58 patients did a cycle consisting of a treatment of 12 days per year for three consecutive years; 37 patients followed the same procedure for 5 years consecutively. The control population was represented by untreated, age-matched children. A standard audiometric test was used before and after each cycle of treatment. One cycle of Politzer inhalation of sulphur-rich water improved the symptoms. Three cycles definitively stabilized the improvement of hearing function. Our results show that otitis media with effusion in children can be resolved by an appropriate non-pharmacological treatment of middle ear with sulphur-rich water.

PyFLOWGO: An open-source platform for simulation of channelized lava thermo-rheological properties

Science.gov (United States)

Chevrel, Magdalena Oryaëlle; Labroquère, Jérémie; Harris, Andrew J. L.; Rowland, Scott K.

2018-02-01

Lava flow advance can be modeled through tracking the evolution of the thermo-rheological properties of a control volume of lava as it cools and crystallizes. An example of such a model was conceived by Harris and Rowland (2001) who developed a 1-D model, FLOWGO, in which the velocity of a control volume flowing down a channel depends on rheological properties computed following the thermal path estimated via a heat balance box model. We provide here an updated version of FLOWGO written in Python that is an open-source, modern and flexible language. Our software, named PyFLOWGO, allows selection of heat fluxes and rheological models of the user's choice to simulate the thermo-rheological evolution of the lava control volume. We describe its architecture which offers more flexibility while reducing the risk of making error when changing models in comparison to the previous FLOWGO version. Three cases are tested using actual data from channel-fed lava flow systems and results are discussed in terms of model validation and convergence. PyFLOWGO is open-source and packaged in a Python library to be imported and reused in any Python program (https://github.com/pyflowgo/pyflowgo)

Mesoporous iron–manganese oxides for sulphur mustard and soman degradation

Energy Technology Data Exchange (ETDEWEB)

Štengl, Václav, E-mail: stengl@iic.cas.cz [Department of Solid State Chemistry, Institute of Inorganic Chemistry AS CR, v.v.i., 250 68 Řež (Czech Republic); J.E. Purkyně University in Ústí nad Labem, Faculty of Environment, 400 96 Ústí nad Labem (Czech Republic); Grygar, Tomáš Matys [Department of Solid State Chemistry, Institute of Inorganic Chemistry AS CR, v.v.i., 250 68 Řež (Czech Republic); J.E. Purkyně University in Ústí nad Labem, Faculty of Environment, 400 96 Ústí nad Labem (Czech Republic); Bludská, Jana [Department of Solid State Chemistry, Institute of Inorganic Chemistry AS CR, v.v.i., 250 68 Řež (Czech Republic); Opluštil, František; Němec, Tomáš [Military Technical Institute of Protection Brno, Veslařská 230, 628 00 Brno (Czech Republic)

2012-12-15

Graphical abstract: Display Omitted Highlights: ► New nanodispersive materials based on Fe and Mn oxides for degradations of warfare agents. ► The best activities for the degradation of sulphur mustard (97.9% in 64 min) and soman (97.9% in 64 min). ► One pot synthesis with friendly transformed to industrial conditions. -- Abstract: Substituted iron(III)–manganese(III, IV) oxides, ammonio-jarosite and birnessite, were prepared by a homogeneous hydrolysis of potassium permanganate and iron(III) sulphate with 2-chloroacetamide and urea, respectively. Synthesised oxides were characterised using Brunauer–Emmett–Teller (BET) surface area and Barrett–Joiner–Halenda porosity (BJH), X-ray diffraction (XRD), infrared spectroscopy (IR), Raman spectroscopy and scanning electron microscopy (SEM). The oxides were taken for an experimental evaluation of their reactivity against sulphur mustard (HD) and soman (GD). When ammonio-jarosite formation is suppressed by adding urea to the reaction mixture, the reaction products are mixtures of goethite, schwertmannite and ferrihydrite, and their degradation activity against soman considerably increases. The best activities for the degradation of sulphur mustard (97.9% in 64 min) and soman (97.9% in 64 min) were observed for FeMn{sub 7}5 with 32.6 wt.% Fe (36.8 wt.% Mn) and FeMn{sub 3}7U with 60.8 wt.% Fe (10.1 wt.% Mn) samples, respectively.

Mesoporous iron–manganese oxides for sulphur mustard and soman degradation

International Nuclear Information System (INIS)

Štengl, Václav; Grygar, Tomáš Matys; Bludská, Jana; Opluštil, František; Němec, Tomáš

2012-01-01

Graphical abstract: Display Omitted Highlights: ► New nanodispersive materials based on Fe and Mn oxides for degradations of warfare agents. ► The best activities for the degradation of sulphur mustard (97.9% in 64 min) and soman (97.9% in 64 min). ► One pot synthesis with friendly transformed to industrial conditions. -- Abstract: Substituted iron(III)–manganese(III, IV) oxides, ammonio-jarosite and birnessite, were prepared by a homogeneous hydrolysis of potassium permanganate and iron(III) sulphate with 2-chloroacetamide and urea, respectively. Synthesised oxides were characterised using Brunauer–Emmett–Teller (BET) surface area and Barrett–Joiner–Halenda porosity (BJH), X-ray diffraction (XRD), infrared spectroscopy (IR), Raman spectroscopy and scanning electron microscopy (SEM). The oxides were taken for an experimental evaluation of their reactivity against sulphur mustard (HD) and soman (GD). When ammonio-jarosite formation is suppressed by adding urea to the reaction mixture, the reaction products are mixtures of goethite, schwertmannite and ferrihydrite, and their degradation activity against soman considerably increases. The best activities for the degradation of sulphur mustard (97.9% in 64 min) and soman (97.9% in 64 min) were observed for FeMn 7 5 with 32.6 wt.% Fe (36.8 wt.% Mn) and FeMn 3 7U with 60.8 wt.% Fe (10.1 wt.% Mn) samples, respectively.

Studies on uptake and translocation of sulphur in oil seed rape plant using 35S tracer technique

International Nuclear Information System (INIS)

Zhang Qinzheng; Wang Xiaochang

1995-01-01

The experiments were conducted to investigate the uptake and translocation of 35 S in oil seed rape at different stages. The results showed that uptake of sulphur from soil by rape plant were 23.59%, 31.65% and 49.13% of sulphur applied at transplanting, bolting and flowering stage, respectively. About 40% of 35 S taken from soil was located in seeds for transplanting and flowering stage applying. About 20% of sulphur applied on top four leaves at various stages of growth was remained in labelled leaves and 21%∼23% was transported to pods with majority in branch pods. 40%∼60% of sulphur which was applied on surface of pods at lower stem at different time after flowering was remained in shell of labelled pods and 13%∼16.8% of that was transferred into seeds of labelled pods. Recoveries of labelled sulphur applied on pods from seeds of pods at branches were less than 10%. The transportation of 35 S from labelled sites to seeds of labelled pods and unlabelled pods was declined sharply as labelling was carried out at 6 weeks after flowering

Effects of changes in the UK energy demand and environmental legislation on atmospheric pollution by sulphur dioxide

International Nuclear Information System (INIS)

Blakemore, F.B.; Davies, C.; Isaac, J.G.

1999-01-01

Ninety-nine percent of the sulphur dioxide generated over the period 1970 to 1994 arose from the combustion of fossil fuels in the energy sector. The annual mass emission of sulphur dioxide has fallen by 58% over this period, due to the reductions in outputs from coal and petroleum fired plants. The influence of natural-gas power generation has played an important part in this reduction. Four major pieces of environmental legislation have been enacted to control sulphur-dioxide emissions: the Control of Pollution Act 1974, and three EEC Directives are discussed. The UK emissions in 1994 were 49% below the 1980 baseline and 9% ahead of the 1998 EU target level. The protocol on the reduction of sulphur-dioxide emissions, adopted in 1985, required a cut in the total SO 2 emissions of 30% by 1993, based on 1980 levels. The UK achieved a reduction of 37% by the end of 1993. Sulphur-dioxide emissions are predicted to fall according to the six scenarios in Energy paper 65 as a reference case. The predicted decline is in line with the UNECE targets set for 2010. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

Primordial helium abundance determination using sulphur as metallicity tracer

Science.gov (United States)

Fernández, Vital; Terlevich, Elena; Díaz, Angeles I.; Terlevich, Roberto; Rosales-Ortega, F. F.

2018-05-01

The primordial helium abundance YP is calculated using sulphur as metallicity tracer in the classical methodology (with YP as an extrapolation of Y to zero metals). The calculated value, YP, S = 0.244 ± 0.006, is in good agreement with the estimate from the Planck experiment, as well as, determinations in the literature using oxygen as the metallicity tracer. The chemical analysis includes the sustraction of the nebular continuum and of the stellar continuum computed from simple stellar population synthesis grids. The S+2 content is measured from the near infrared [SIII]λλ9069Å, 9532Å lines, while an ICF(S3 +) is proposed based on the Ar3 +/Ar2 + fraction. Finally, we apply a multivariable linear regression using simultaneously oxygen, nitrogen and sulphur abundances for the same sample to determine the primordial helium abundance resulting in YP - O, N, S = 0.245 ± 0.007.

Influence of sediment recycling on the trace element composition of primitive arc lavas

Science.gov (United States)

Collinet, M.; Jagoutz, O. E.

2017-12-01

Primitive calc-alkaline lavas from continental arcs are, on average, enriched in incompatible elements compared to those from intra-oceanic arcs. This relative enrichment is observed in different groups of trace elements: LILE (e.g. K, Rb), LREE to MREE (La-Dy) and HFSE (e.g.Zr, Nb) and is thought to result from (1) a transfer of material from the subducting slab to the mantle wedge at higher temperature than in intra-oceanic margins and/or (2) lower average degrees of melting in the mantle wedge, as a consequence of thicker overlying crusts and higher average pressures of melting. In addition to thicker overlying crusts and generally higher slab temperatures, continental margins are characterized by larger volumes of rock exposed above sea level and enhanced erosion rates compared to intra-oceanic arcs. As several geochemical signatures of arc lavas attest to the importance of sediment recycling in subduction zones, we explore the possibility that the high concentrations of incompatible elements in primitive lavas from continental arcs directly reflect a larger input of sediment to the subduction system. Previous efforts to quantify the sediment flux to oceanic trenches focused on the thickness of pelagic and hemipelagic sediments on top of the plate entering the subduction zone (Plank and Langmuir, 1993, Nature). These estimates primarily relied on the sediment layer drilled outboard from the subduction system and likely underestimate the volume of sediment derived from the arc itself. Accordingly, we find that such estimates of sediment flux do not correlate with the concentration of incompatible elements in primitive arc lavas. To account for regional contributions of coarser detrital sediments, usually delivered to oceanic trenches by turbidity currents, we apply to arc segments a model that quantifies the sediment load of rivers based on the average relief, area, temperature and runoff of their respective drainage areas (Syvitski et al., 2003, Sediment. Geol

Continuous terrestrial geodetic monitoring of the 2007 Lava Fan in the Sciara de Fuoco (Stromboli volcano, Italy)

Science.gov (United States)

Puglisi, G.; Bonforte, A.; Cantarero, M.; Spata, A.

2009-12-01

At the end of the 2002-2003 eruption, a terrestrial monitoring system was set up to regularly measure the movements of benchmarks installed inside the Sciara del Fuoco (hereafter SdF) (Puglisi et al., 2005). This system, named THEODOROS, is based on a remotely controlled robotized Total Station installed near Punta Labronzo, on the northern border of the SdF. The 2007 eruption caused a dramatic change in the operations of THEODOROS. Indeed, the 2007 lava flows destroyed all the benchmarks installed on the northern part of the SdF, leaving only those on its central part. This eruption produced a lava fan at the base of the SdF, due to the rapid cooling of the lava flows on entering the sea. The continuous overlapping of several flows during the eruption built a thick lava body (the fan); it was emplaced on a very steep slope, partially originated during the landslides occurring in December 2002, producing a hazardous condition due to the potential sudden sliding of this fan into the sea. In order to monitor the stability of this lava fan, a new terrestrial geodetic network, was implemented on 6 April 2007, by installing 5 reflectors along a profile crossing the lava body, approximately over the old coastline. Later, in June 2007, 4 more reflectors were installed at higher and lower altitudes with respect to the previous profile, to obtain more information on the overall deformation of the lava body. Measurements were rather noisy during the first months, but a better definition of the reference system strongly improved the quality of the data. The position of the 9 benchmarks over the lava fan enable the areal distribution of the deformation to be drawn. The measurements carried out every 10 minutes allow following their motion with high temporal detail. The data collected since the end of the eruption highlighted a significant downslope motion of the entire lava fan, decreasing from the South to the North, where the body is buttressed by the rocky northern wall of

78 FR 64003 - Notice of Availability of the Final Environmental Impact Statement for the Jump Creek, Succor...

Science.gov (United States)

2013-10-25

...] Notice of Availability of the Final Environmental Impact Statement for the Jump Creek, Succor Creek, and... Field Office Jump Creek, Succor Creek and Cow Creek Watersheds grazing permit renewal, and by this... in the Federal Register. ADDRESSES: Copies of the Jump Creek, Succor Creek and Cow Creek Watersheds...

Susceptibility of lava domes to erosion and collapse by toppling on cooling joints

Science.gov (United States)

Smith, John V.

2018-01-01

The shape of lava domes typically leads to the formation of radial patterns of cooling joints. These cooling joints define the orientation of the columnar blocks which plunge toward the center of the dome. In the lower parts of the dome the columns plunge into the dome at low angles and are relatively stable. Higher in the dome the columns plunge into the dome at steep angles. These steeply plunging columns are susceptible to toppling and, if the lower part of a dome is partially removed by erosion or collapse, the unstable part of the dome becomes exposed leading to toppling failure. Examples of this process are provided from coastal erosion of lava domes at Katsura Island, Shimane Peninsula, western Japan. An analogue model is presented to demonstrate the mechanism. It is proposed that the mechanism can contribute to collapse of lava domes during or after emplacement.

78 FR 26065 - Notice of Availability of the Draft Environmental Impact Statement for the Jump Creek, Succor...

Science.gov (United States)

2013-05-03

...] Notice of Availability of the Draft Environmental Impact Statement for the Jump Creek, Succor Creek, and... the Jump Creek, Succor Creek, and Cow Creek Watersheds Grazing Permit Renewal and by this notice is... receive written comments on the Draft EIS for the Jump Creek, Succor Creek, and Cow Creek Watersheds...

Hawaii Lava Flows

Science.gov (United States)

2001-01-01

This sequence of ASTER nighttime thermal images shows the Pu'u O'o lava flows entering the sea at Kamokuna on the southeast side of the Island of Hawaii. Each image covers an area of 9 x 12 km. The acquisition dates are April 4 2000, May 13 2000, May 22 2000 (upper row) and June 30 2000, August 1 2000 and January 1 2001 (lower row). Thermal band 14 has been color coded from black (coldest) through blue, red, yellow and white (hottest). The first 5 images show a time sequence of a single eruptive phase; the last image shows flows from a later eruptive phase. The images are located at 19.3 degrees north latitude, 155 degrees west longitude. The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

Eruption and emplacement dynamics of a thick trachytic lava flow of the Sancy volcano (France)

Science.gov (United States)

Latutrie, Benjamin; Harris, Andrew; Médard, Etienne; Gurioli, Lucia

2017-01-01

A 70-m-thick, 2200-m-long (51 × 106 m3) trachytic lava flow unit underlies the Puy de Cliergue (Mt. Dore, France). Excellent exposure along a 400-m-long and 60- to 85-m-high section allows the flow interior to be accessed on two sides of a glacial valley that cuts through the unit. We completed an integrated morphological, structural, textural, and chemical analysis of the unit to gain insights into eruption and flow processes during emplacement of this thick silicic lava flow, so as to elucidate the chamber and flow dynamic processed that operate during the emplacement of such systems. The unit is characterized by an inverse chemical stratification, where there is primitive lava beneath the evolved lava. The interior is plug dominated with a thin basal shear zone overlying a thick basal breccia, with ramping affecting the entire flow thickness. To understand these characteristics, we propose an eruption model that first involves processes operating in the magma chamber whereby a primitive melt is injected into an evolved magma to create a mixed zone at the chamber base. The eruption triggered by this event first emplaced a trachytic dome, into which banded lava from the chamber base was injected. Subsequent endogenous dome growth led to flow down the shallow slope to the east on which the highly viscous (1012 Pa s) coulée was emplaced. The flow likely moved extremely slowly, being emplaced over a period of 4-10 years in a glacial manner, where a thick (>60-m) plug slid over a thin (5-m-thick) basal shear zone. Excellent exposure means that the Puy de Cliergue complex can be viewed as a case type location for understanding and defining the eruption and emplacement of thick, high-viscosity, silicic lava flow systems.

Pine Creek Ranch, FY 2001 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Berry, Mark E.

2001-11-01

Pine Creek Ranch was purchased in 1999 by the Confederated Tribes of Warm Springs using Bonneville Power Administration Fish and Wildlife Habitat Mitigation funds. The 25,000 acre property will be managed in perpetuity for the benefit of fish and wildlife habitat. Major issues include: (1) Restoring quality spawning and rearing habitat for stealhead. Streams are incised and fish passage barriers exist from culverts and possibly beaver dams. In addition to stealhead habitat, the Tribes are interested in overall riparian recovery in the John Day River system for wildlife habitat, watershed values and other values such as recreation. (2) Future grazing for specific management purposes. Past grazing practices undoubtedly contributed to current unacceptable conditions. The main stem of Pine Creek has already been enrolled in the CREP program administered by the USDA, Natural Resource Conservation Service in part because of the cost-share for vegetation restoration in a buffer portion of old fields and in part because of rental fees that will help the Tribes to pay the property taxes. Grazing is not allowed in the riparian buffer for the term of the contract. (3) Noxious weeds are a major concern. (4) Encroachment by western juniper throughout the watershed is a potential concern for the hydrology of the creek. Mark Berry, Habitat Manager, for the Pine Creek Ranch requested the Team to address the following objectives: (1) Introduce some of the field staff and others to Proper Functioning Condition (PFC) assessments and concepts. (2) Do a PFC assessment on approximately 10 miles of Pine Creek. (3) Offer management recommendations. (4) Provide guidelines for monitoring.

Effects of best-management practices in Eagle and Joos Valley Creeks in the Waumandee Creek Priority Watershed, Wisconsin, 1990-2007

Science.gov (United States)

Graczyk, David J.; Walker, John F.; Bannerman, Roger T.; Rutter, Troy D.

2012-01-01

In many watersheds, nonpoint-source contamination is a major contributor to water-quality problems. In response to the recognition of the importance of nonpoint sources, the Wisconsin Nonpoint Source Water Pollution Abatement Program (Nonpoint Program) was enacted in 1978. This report summarizes the results of a study to assess the effectiveness of watershed-management practices for controlling nonpoint-source contamination for the Eagle Creek and Joos Valley Creek Watersheds. Streamflow-gaging stations equipped for automated sample collection and continuous recording of stream stage were installed in July 1990 at Eagle and Joos Valley Creeks and were operated through September 2007. In October 1990, three rain gages were installed in each watershed and were operated through September 2007. Best-Management Practices (BMPs) were installed during 1993 to 2000 in Eagle and Joos Valley Creeks and were tracked throughout the study period. By the year 2000, a majority of the BMPs were implemented in the two watersheds and goals set by the Wisconsin Department of Natural Resources and the local Land Conservation Department had been achieved for the two study watersheds (Wisconsin Department of Natural Resources, 1990). The distributions of the rainstorms that produced surface runoff and storm loads were similar in the pre-BMP (1990-93) and post-BMP implementation (2000-07) periods for both Eagle and Joos Valley Creeks. The highest annual streamflow occurred at both sites in water year 1993, which corresponded to the greatest above normal nonfrozen precipitation measured at two nearby NOAA weather stations. The minimum streamflow occurred in water year 2007 at both sites. Base-flow and stormwater samples were collected and analyzed for suspended solids, total phosphorus, and ammonia nitrogen. For both Eagle and Joos Valley Creeks the median concentrations of suspended solids and total phosphorus in base flow were lower during the post-BMP period compared to the pre

effects of sulphur addition on addition on and mechanical properties

African Journals Online (AJOL)

User

234-8034714355. 8034714355. 1. EFFECTS OF SULPHUR ADDITION ON. ADDITION ON. 2. AND MECHANICAL PROPERTIES O. 3. 4. C. W. Onyia. 5. 1DEPT. OF METALLURGICAL AND MATERIALS. 6. 2, 4DEPT. OF METALLURGICAL ...

Chlorine- and Sulphur-substituted Pyrrolo[3,4-b]quinolines and ...

African Journals Online (AJOL)

Chlorine- and Sulphur-substituted Pyrrolo[3,4-b]quinolines and Related Derivatives .... J. Chem., 2003, 56, 40–46,. . .... It is evident from the above that by judicious selection and application of reagents ...

Streamflow conditions along Soldier Creek, Northeast Kansas

Science.gov (United States)

Juracek, Kyle E.

2017-11-14

The availability of adequate water to meet the present (2017) and future needs of humans, fish, and wildlife is a fundamental issue for the Prairie Band Potawatomi Nation in northeast Kansas. Because Soldier Creek flows through the Prairie Band Potawatomi Nation Reservation, it is an important tribal resource. An understanding of historical Soldier Creek streamflow conditions is required for the effective management of tribal water resources, including drought contingency planning. Historical data for six selected U.S. Geological Survey (USGS) streamgages along Soldier Creek were used in an assessment of streamflow characteristics and trends by Juracek (2017). Streamflow data for the period of record at each streamgage were used to compute annual mean streamflow, annual mean base flow, mean monthly flow, annual peak flow, and annual minimum flow. Results of the assessment are summarized in this fact sheet.

Cellulose sulphuric acid as a biodegradable catalyst for conversion ...

Indian Academy of Sciences (India)

This article describes simple and efficient method for the diazotization and azidation of different aromatic amines over cellulose sulphuric acid, sodium nitrite and sodium azide under mild conditions at room temperature. Various aryl amines possessing electron-withdrawing groups or electron-donating groups have been ...

Past and future trends in concentrations of sulphur and nitrogen compounds in the Arctic

DEFF Research Database (Denmark)

Hole, Lars R.; Christensen, Jesper H.; Ruoho-Airola, Tuija

2009-01-01

Recent trends in nitrogen and sulphur compounds in air and precipitation from a range of Arctic monitoring stations are presented, with seasonal data from the late 70s to 2004 or 2005. Earlier findings of declining sulphur concentrations are confirmed for most stations, while the pattern is less...... clear for reduced and oxidized nitrogen. In fact there are positive trends for nitrogen compounds in air at several stations. Acidity is generally reduced at many stations while the precipitation amount is either increasing or stable. Variability of sulphate concentrations in air for the period 1991......-2000 is reasonably well reproduced at most stations using an Eulerian, hemispherical model. Results for nitrogen compounds are weaker. Scenario studies show that even if large sulphur emission reductions take place in important source regions in South-East Asia in the coming decades, only small changes in Arctic...

Continental scale Antarctic deposition of sulphur and black carbon from anthropogenic and volcanic sources

Directory of Open Access Journals (Sweden)

H.-F. Graf

2010-03-01

Full Text Available While Antarctica is often described as a pristine environment, there is an increasing awareness of the potential threats from local pollution sources including tourist ships and emissions associated with scientific activities. However, to date there has been no systematic attempt to model the impacts of such pollutants at the continental scale. Indeed, until very recently there was not even a sulphur emission budget available for Antarctica. Here we present the first comprehensive study of atmospheric pollution in Antarctica using a limited area chemistry climate model, and a monthly emissions inventory for sulphur from maintenance of research stations, ground and air traffic, shipping and the active Erebus volcano. We find that ship emissions, both sulphurous and black carbon, dominate anthropogenic pollution near the ground. Their prevalence is likely to rise dramatically if recent trends in tourism continue.

Bismuth ions are metabolized into autometallographic traceable bismuth-sulphur quantum dots

Directory of Open Access Journals (Sweden)

M Stoltenberg

2009-06-01

Full Text Available Bismuth – sulphur quantum dots can be silver enhanced by autometallography (AMG. In the present study, autometallographic silver enhanced bismuth-sulphur nanocrystals were isolated from unfixed cryo-sections of kidneys and livers of rats exposed to bismuth (Bi207 subnitrate. After being subjected to AMG all the organic material was removed by sonication and enzymatic digestion and the silver enhanced Bi- S quantum dots spun down by an ultracentrifuge and analyzed by scintillation. The analysis showed that the autometallographic technique traces approximately 94% of the total bismuth. This implies that the injected bismuth is ultimately captured in bismuthsulphur quantum dots, i.e., that Bi-S nanocrystals are the end product of bismuth metabolism

Communicating Science to Officials and People at Risk During a Slow-Motion Lava Flow Crisis

Science.gov (United States)

Neal, C. A.; Babb, J.; Brantley, S.; Kauahikaua, J. P.

2015-12-01

From June 2014 through March 2015, Kīlauea Volcano's Púu ´Ō´ō vent on the East Rift Zone produced a tube-fed pāhoehoe lava flow -the "June 27th flow" - that extended 20 km downslope. Within 2 months of onset, flow trajectory towards populated areas in the Puna District caused much concern. The USGS Hawaiian Volcano Observatory (HVO) issued a news release of increased hazard on August 22 and began participating in public meetings organized by Hawai`i County Mayor and Civil Defense two days later. On September 4, HVO upgraded the volcano alert level to WARNING based on an increased potential for lava to reach homes and infrastructure. Ultimately, direct impacts were modest: lava destroyed one unoccupied home and one utility pole, crossed a rural roadway, and partially inundated a waste transfer station, a cemetery, and agricultural land. Anticipation that lava could reach Pāhoa Village and cross the only major access highway, however, caused significant disruption. HVO scientists employed numerous methods to communicate science and hazard information to officials and the at-risk public: daily (or more frequent) written updates of the lava activity, flow front locations and advance rates; frequent updates of web-hosted maps and images; use of the 'lines of steepest descent' method to indicate likely lava flow paths; consistent participation in well-attended community meetings; bi-weekly briefings to County, State, and Federal officials; correspondence with the public via email and recorded phone messages; participation in press conferences and congressional briefings; and weekly newspaper articles (Volcano Watch). Communication lessons both learned and reinforced include: (1) direct, frequent interaction between scientists and officials and at-risk public builds critical trust and understanding; (2) images, maps, and presentations must be tailored to audience needs; (3) many people are unfamiliar with maps (oblique aerial photographs were more effective); (4

Mantle sources and magma evolution of the Rooiberg lavas, Bushveld Large Igneous Province, South Africa

Science.gov (United States)

Günther, T.; Haase, K. M.; Klemd, R.; Teschner, C.

2018-06-01

We report a new whole-rock dataset of major and trace element abundances and 87Sr/86Sr-143Nd/144Nd isotope ratios for basaltic to rhyolitic lavas from the Rooiberg continental large igneous province (LIP). The formation of the Paleoproterozoic Rooiberg Group is contemporaneous with and spatially related to the layered intrusion of the Bushveld Complex, which stratigraphically separates the volcanic succession. Our new data confirm the presence of low- and high-Ti mafic and intermediate lavas (basaltic—andesitic compositions) with > 4 wt% MgO, as well as evolved rocks (andesitic—rhyolitic compositions), characterized by MgO contents of N, Nb/Y and Ti/Y), indicating a different petrogenesis. MELTS modelling shows that the evolved lavas are formed by fractional crystallization from the mafic low-Ti lavas at low-to-moderate pressures ( 4 kbar). Primitive mantle-normalized trace element patterns of the Rooiberg rocks show an enrichment of large ion lithophile elements (LILE), rare-earth elements (REE) and pronounced negative anomalies of Nb, Ta, P, Ti and a positive Pb anomaly. Unaltered Rooiberg lavas have negative ɛNdi (- 5.2 to - 9.4) and radiogenic ɛSri (6.6 to 105) ratios (at 2061 Ma). These data overlap with isotope and trace element compositions of purported parental melts to the Bushveld Complex, especially for the lower zone. We suggest that the Rooiberg suite originated from a source similar to the composition of the B1-magma suggested as parental to the Bushveld Lower Zone, or that the lavas represent eruptive successions of fractional crystallization products related to the ultramafic cumulates that were forming at depth. The Rooiberg magmas may have formed by 10-20% crustal assimilation by the fractionation of a very primitive mantle-derived melt within the upper crust of the Kaapvaal Craton. Alternatively, the magmas represent mixtures of melts from a primitive, sub-lithospheric mantle plume and an enriched sub-continental lithospheric mantle (SCLM

Reactive extraction and recovery of levulinic acid, formic acid and furfural from aqueous solutions containing sulphuric acid

NARCIS (Netherlands)

Brouwer, Thomas; Blahusiak, Marek; Babic, Katarina; Schuur, Boelo

2017-01-01

Levulinic acid (LA) can be produced from lignocellulosic materials via hydroxylation followed by an acid-catalyzed conversion of hexoses. Inorganic homogeneous catalysts are mostly used, in particular sulphuric acid, yielding a mixture of LA with sulphuric acid, formic acid (FA) and furfural.

Missing link between the Hayward and Rodgers Creek faults.

Science.gov (United States)

Watt, Janet; Ponce, David; Parsons, Tom; Hart, Patrick

2016-10-01

The next major earthquake to strike the ~7 million residents of the San Francisco Bay Area will most likely result from rupture of the Hayward or Rodgers Creek faults. Until now, the relationship between these two faults beneath San Pablo Bay has been a mystery. Detailed subsurface imaging provides definitive evidence of active faulting along the Hayward fault as it traverses San Pablo Bay and bends ~10° to the right toward the Rodgers Creek fault. Integrated geophysical interpretation and kinematic modeling show that the Hayward and Rodgers Creek faults are directly connected at the surface-a geometric relationship that has significant implications for earthquake dynamics and seismic hazard. A direct link enables simultaneous rupture of the Hayward and Rodgers Creek faults, a scenario that could result in a major earthquake ( M = 7.4) that would cause extensive damage and loss of life with global economic impact.

American pika in a low-elevation lava landscape: expanding the known distribution of a temperature-sensitive species.

Science.gov (United States)

Shinderman, Matt

2015-09-01

In 2010, the American pika (Ochotona princeps fenisex) was denied federal protection based on limited evidence of persistence in low-elevation environments. Studies in nonalpine areas have been limited to relatively few environments, and it is unclear whether patterns observed elsewhere (e.g., Bodie, CA) represent other nonalpine habitats. This study was designed to establish pika presence in a new location, determine distribution within the surveyed area, and evaluate influences of elevation, vegetation, lava complexity, and distance to habitat edge on pika site occupancy. In 2011 and 2012, we conducted surveys for American pika on four distinct subalpine lava flows of Newberry National Volcanic Monument, Oregon, USA. Field surveys were conducted at predetermined locations within lava flows via silent observation and active searching for pika sign. Site habitat characteristics were included as predictors of occupancy in multinomial regression models. Above and belowground temperatures were recorded at a subsample of pika detection sites. Pika were detected in 26% (2011) and 19% (2012) of survey plots. Seventy-four pika were detected outside survey plot boundaries. Lava complexity was the strongest predictor of pika occurrence, where pika were up to seven times more likely to occur in the most complicated lava formations. Pika were two times more likely to occur with increasing elevation, although they were found at all elevations in the study area. This study expands the known distribution of the species and provides additional evidence for persistence in nonalpine habitats. Results partially support the predictive occupancy model developed for pika at Craters of the Moon National Monument, another lava environment. Characteristics of the lava environment clearly influence pika site occupancy, but habitat variables reported as important in other studies were inconclusive here. Further work is needed to gain a better understanding of the species' current

Effects of Different Forms and Doses of Sulphur Application on Wheat

Directory of Open Access Journals (Sweden)

Halil Erdem

2016-11-01

Full Text Available Deficiency of sulphur (S is an important limiting factor of plant growth for sustainable agricultural production. The decline in sulphur dioxide emission, decrease in S-containing fertilizer consumption due to the high cost of S-fertilizers, breeding of new high yielding species are the well known causes of S-deficiency. A greenhouse experiment was conducted to investigate the effects of several doses of K2SO4-S, CaSO4-S and elemental-S applied on growth, shoot dry matter yield, S and N concentrations of wheat cultivar. The experiments were conducted in three soils differed from available S concentrations. Effects of different S-treatments (0, 25, 50 and 100 mg S kg-1 and S-forms had significant effects on shoot dry matter yields of plants. Sulphur from different S-sources did not increase shoot S-concentrations in Eskisehir and Konya soils, but increase was significant obtained in the Harran soil. Shoot S-concentration in Harran soil for zero K2SO4 treatment was 0.09%, the values were 0.22, 0.26 and 0.27% respectively for 25, 50 and 100 mg kg-1 treatments. The results indicated significant effects of S-treatments on plant growth and yield mostly based on soil properties, especially the available S-levels

Wisata Bencana : Sebuah Studi Kasus Lava Tour Gunung Merapi

Directory of Open Access Journals (Sweden)

Zein Mufarrih Muktaf

2017-09-01

ABSTRACK The emergence of ecotourism trends as part of nature tourism to be an offer for tourists who want to feel the sensation of different tourist. In addition to the emergence of ecotourism, also appeared many other sort of tourism, such as dark tourism and disaster tourism. Dark tourism and disaster tourism is interesting enough to be discussion. The quention of this research is how the phenomenon of disaster tourism on Lava Tour in Mount Merapi? The purpose of this research is to know the practice of disaster tour “Lava Tour” Mount Merapi. The object of research is community-based tourism in Lava Tour area located in Disaster Prone Area (Kawasan Rawan Bencana III. Research method using case study approach. The conclusion of this research is, first, disaster tour is educational tour which destruction, death and back a life as tourist attraction. Secondly, that disaster tour presents a trip or tour because tourists can direct to see the disaster site. Third, the role of communication between the community-based tourism to the tourists are very important, such as telling the chronology of events to the tourists. It is better if the source of information teller is a direct victim or a direct eye witness, because it is more authentic and convincing. Fourth, disaster tourism prefers the interaction between witnesses and tourists. Fifth, disaster tours can be part of disaster literacy, as witnesses or victims explain a lot about disaster. Keywod : disaster tourism; tour; Mount Merapi; Tourism Communication; disaster literacy

Development of the floating sulphur biofilm reactor for sulphide ...

African Journals Online (AJOL)

driniev

The formation of floating sulphur biofilm was observed in the microbial ecology studies of tannery ponds undertaken by the. Environmental Biotechnology Group at Rhodes University. This was related to the steep Redox gradients established at the air/ water interface of anaerobic, organically loaded and actively sulphate ...

Investigating the Maya Polity at Lower Barton Creek Cayo, Belize

Science.gov (United States)

Kollias, George Van, III

The objectives of this research are to determine the importance of Lower Barton Creek in both time and space, with relation to other settlements along the Belize River Valley. Material evidence recovered from field excavations and spatial information developed from Lidar data were employed in determining the socio-political nature and importance of this settlement, so as to orient its existence within the context of ancient socio-political dynamics in the Belize River Valley. Before the investigations detailed in this thesis no archaeological research had been conducted in the area, the site of Lower Barton Creek itself was only recently identified via the 2013 West-Central Belize LiDAR Survey (WCBLS 2013). Previously, the southern extent of the Barton Creek area represented a major break in our knowledge not only of the Barton Creek area, but the southern extent of the Belize River Valley. Conducting research at Lower Barton Creek has led to the determination of the polity's temporal existence and allowed for a greater and more complex understanding of the Belize River Valley's interaction with regions abutting the Belize River Valley proper.

Short communication: Laboratory approach to the use of sulphur and kaolin as preventive control against Drosophila suzukii