Science.gov

Sample records for accelerated limestone weathering

  1. CO2 mitigation via accelerated limestone weathering

    USGS Publications Warehouse

    Rau, Greg H.; Knauss, Kevin G.; Langer, William H.; Caldeira,

    2004-01-01

    We evaluate accelerated weathering of limestone (AWL: CO2 + CaCO3 + H2O=> Ca2+ + 2HCO3-) as a low-tech, inexpensive, high-capacity, environmentally-friendly CO2 capture and sequestration technology. With access to seawater and limestone being essential to this approach, significant limestone resources are close to most CO2-emitting power plants along the coastal US. Waste fines, representing more than 20% of current US crushed limestone production (>109 tonnes/yr), could be used as an inexpensive source of AWL carbonate. Under such circumstances CO2 mitigation cost could be as low as $3-$4/tonne. More broadly, 10-20% of US point-source CO2 emissions could be treated at $20-$30/tonne CO2. AWL end-solution disposal in the ocean would significantly reduce effects on ocean pH and carbonate chemistry relative to those caused by direct atmospheric or ocean CO2 disposal. Indeed, the increase in ocean Ca2+ and bicarbonate offered by AWL should enhance growth of corals and other calcifying marine organisms.

  2. CO2 MITIGATION VIA ACCELERATED LIMESTONE WEATHERING

    SciTech Connect

    Rau, G H; Knauss, K G; Langer, W H; Caldeira, K G

    2004-02-27

    The climate and environmental impacts of our current, carbon-intensive energy usage demands that effective and practical energy alternatives and CO2 mitigation strategies be found. As part of this effort, various means of capturing and storing CO2 generated from fossil-fuel-based energy production are being investigated. One of the proposed methods involves a geochemistry-based capture and sequestration process that hydrates point-source, waste CO2 with water to produce a carbonic acid solution. This in turn is reacted and neutralized with limestone, thus converting the original CO2 gas to calcium bicarbonate in solution, the overall reaction being:

  3. Limestone weathering rates accelerated by micron-scale grain detachment

    NASA Astrophysics Data System (ADS)

    Emmanuel, S.; Levenson, Y.

    2014-12-01

    The weathering rates of carbonate rocks is often thought to be controlled by chemical dissolution, although some studies have suggested that mechanical erosion could also play an important role. Quantifying the rates of the different processes has proved challenging due to the high degree of variability encountered in both field and lab settings. To determine the rates and mechanisms controlling long-term limestone weathering, we analyse a lidar scan of the Western Wall, a Roman period edifice located in Jerusalem. Weathering rates in fine-grained micritic limestone blocks are up to 2 orders of magnitude higher than the average rates estimated for coarse-grained limestone blocks at the same site. In addition, in experiments that use atomic force microscopy to image dissolving micritic limestone, we show that these higher reaction rates could be due to rapid dissolution along micron-scale grain boundaries, followed by mechanical detachment of tiny particles from the surface. Our analysis indicates that micron-scale grain detachment, rather than pure chemical dissolution, could be the dominant erosional mode for fine-grained rocks in many carbonate terrains.

  4. Accelerated weathering of limestone for CO2 mitigation: Opportunities for the stone and cement industries

    USGS Publications Warehouse

    Langer, William H.; San, Juan A.; Rau, Greg H.; Caldeira, Ken

    2009-01-01

    Accelerated weathering of limestone appears to provide a low-tech, inexpensive, high-capacity, environmentally friendly CO2 mitigation method that could be applied to about 200 fossil fuel fired power plants and about eight cement plants located in coastal areas in the conterminous U.S. This approach could also help solve the problem of disposal of limestone waste fines in the crushed stone industry. Research and implementation of this technology will require new collaborative efforts among the crushed stone and cement industries, electric utilities, and the science and engineering communities.

  5. Reducing energy-related CO2 emissions using accelerated weathering of limestone

    USGS Publications Warehouse

    Rau, Greg H.; Knauss, Kevin G.; Langer, William H.; Caldeira, Ken

    2007-01-01

    The use and impacts of accelerated weathering of limestone (AWL; reaction: CO2+H2O+CaCO3→Ca2++2(HCO3-) is explored as a CO2 capture and sequestration method. It is shown that significant limestone resources are relatively close to a majority of CO2-emitting power plants along the coastal US, a favored siting location for AWL. Waste fines, representing more than 20% of current US crushed limestone production (>109 tonnes/yr), could provide an inexpensive or free source of AWL carbonate. With limestone transportation then as the dominant cost variable, CO2 mitigation costs of $3-$4/tonne appear to be possible in certain locations. Perhaps 10–20% of US point–source CO2 emissions could be mitigated in this fashion. It is experimentally shown that CO2 sequestration rates of 10-6 to 10-5 moles/sec per m2 of limestone surface area are achievable, with reaction densities on the order of 10-2 tonnes CO2 m-3day-1, highly dependent on limestone particle size, solution turbulence and flow, and CO2 concentration. Modeling shows that AWL would allow carbon storage in the ocean with significantly reduced impacts to seawater pH relative to direct CO2 disposal into the atmosphere or sea. The addition of AWL-derived alkalinity to the ocean may itself be beneficial for marine biota.

  6. Accelerated weathering of limestone for CO2 mitigation opportunities for the stone and cement industries

    USGS Publications Warehouse

    Langer, W.H.; Juan, C.A.S.; Rau, G.H.; Caldeira, K.

    2009-01-01

    Large amounts of limestone fines coproduced during the processing of crushed limestone may be useful in the sequestration of carbon dioxide (CO 2). Accelerated weathering of limestone (AWL) is proposed as a low-tech method to capture and sequester CO2 from fossil fuel-fired power plants and other point-sources such as cement manufacturing. AWL reactants are readily available, inexpensive, and environmentally benign. Waste CO 2 is hydrated with water to produce carbonic acid, which then reacts with and is neutralized by limestone fines, thus converting CO2 gas to dissolved calcium bicarbonate. AWL waste products can be disposed of in the ocean. Feasibility requires access to an inexpensive source of limestone and to seawater, thus limiting AWL facilities within about 10 km of the coastline. The majority of U.S. coastal power generating facilities are within economical transport distance of limestone resources. AWL presents opportunities for collaborative efforts among the crushed stone industry, electrical utilities, cement manufactures, and research scientists.

  7. Reducing Energy-Related CO2 Emissions Using Accelerated Limestone Weathering

    SciTech Connect

    Rau, G H; Knauss, K G; Langer, W H; Caldeira, K

    2004-04-27

    Following earlier descriptions, the use and impacts of accelerated weathering of limestone AWL; reaction: CO{sub 2} + H{sub 2}O + CaCO{sub 3} {yields} Ca{sup 2+} + 2(HCO{sub 3}{sup -}) as a CO{sub 2} capture and sequestration method is further explored. Since ready access to the ocean is likely an essential requirement for AWL, it is shown that significant limestone resources are relatively close to a majority of CO{sub 2}-emitting power plants along the coastal US. Furthermore, waste fines, representing more than 20% of current US crushed limestone production (>10{sup 9} tonnes/yr), could be used in many instances as an inexpensive or free source of AWL carbonate. With limestone transportation to coastal sites then as the dominant cost variable, CO{sub 2} sequestration (plus capture) costs of $3-$4/tonne are achievable in certain locations. While there is vastly more limestone and water on earth than that required for AWL to capture and sequester all fossil fuel CO{sub 2} production, the transportation cost of bringing limestone, seawater, and waste CO{sub 2} into contact likely limits the method's applicability to perhaps 10-20% of US point-source emissions. Using a bench-scale laboratory reactor, it is shown that CO{sub 2} sequestration rates of 10{sup -6} to 10{sup -5} moles/sec per m{sup 2} of limestone surface area are readily achievable using seawater. This translates into reaction densities as high as 2 x 10{sup -2} tonnes CO{sub 2} m{sup -3}day{sup -1}, highly dependent on limestone particle size, solution turbulence and flow, and CO{sub 2} concentration. Modeling of AWL end-solution disposal in the ocean shows significantly reduced effects on ocean pH and carbonate chemistry relative to those caused by direct CO{sub 2} disposal into the atmosphere or ocean. In fact the increase in ocean Ca{sup 2+} and bicarbonate offered by AWL should significantly enhance the growth of corals and other marine calcifiers whose health is currently being threatened by

  8. Characterizing and modelling 'ghost-rock' weathered limestones

    NASA Astrophysics Data System (ADS)

    Dubois, Caroline; Goderniaux, Pascal; Deceuster, John; Poulain, Angélique; Kaufmann, Olivier

    2016-04-01

    'Ghost-rock' karst aquifer has recently been highlighted. In this particular type of aquifer, the karst is not expressed as open conduits but consists in zones where the limestone is weathered. The in-situ weathering of limestone leaves a soft porous material called 'alterite'. The hydro-mechanical properties of this material differs significantly from those of the host rock: the weathering enhances the storage capacity and the conductivity of the rock. This type of weathered karst aquifer has never been studied from a hydrogeological point of view. In this study, we present the hydraulic characterization of such weathered zones. We also present a modelling approach derived from the common Equivalent Porous Medium (EPM) approach, but including the spatial distribution of hydrogeological properties through the weathered features, from the hard rock to the alterite, according to a weathering index. Unlike the Discrete Fracture Network (DFN) approaches, which enable to take into account a limited number of fractures, this new approach allows creating models including thousands of weathered features. As the properties of the alterite have to be considered at a centimeter scale, it is necessary to upscale these properties to carry out simulations over large areas. Therefore, an upscaling method was developed, taking into account the anisotropy of the weathered features. Synthetic models are built, upscaled and different hydrogeological simulations are run to validate the method. This methodology is finally tested on a real case study: the modelling of the dewatering drainage flow of an exploited quarry in a weathered karst aquifer in Belgium.

  9. Quantifying micron-scale grain detachment during weathering experiments on limestone

    NASA Astrophysics Data System (ADS)

    Levenson, Yael; Emmanuel, Simon

    2016-01-01

    Weathering in carbonate rocks is often assumed to be governed by chemical dissolution. Nevertheless, chemical processes can be coupled to mechanical mechanisms, with small grains undergoing partial dissolution along grain boundaries, followed by detachment from the rock surface. Crucially, this process can even extend down to the micron-scale. Although chemo-mechanical detachment could be critical for the understanding of carbonate weathering at the global scale, the role it plays has not been directly quantified. To calculate the contribution of grain detachment to surface retreat rates, and to determine the impact of the flow regime, we carried out a series of flow-through weathering experiments on micritic limestone. Using atomic force microscopy, we obtained high resolution in situ data of surface topography for reacting rock surfaces. In all the experiments, both grain detachment and chemical dissolution were observed. Under the laminar flow conditions we explored, we found no clear correlation between flow rate and the size of detached grains, or between the flow rate and the frequency of grain detachment events. Importantly, our results establish that grain detachment contributes significantly to the overall surface retreat, on average accelerating mass loss by 38%. In addition to speeding up weathering, this micron-scale mechanism could also influence the evolution of porosity in aquifers and hydrocarbon reservoirs, and provide a natural flux of colloids that could transport heavy metals or radionuclides in groundwater.

  10. Extreme limestone weathering rates due to micron-scale grain detachment

    NASA Astrophysics Data System (ADS)

    Emmanuel, Simon; Levenson, Yael

    2014-05-01

    Chemical dissolution is often assumed to control the weathering rates of carbonate rocks, although some studies have indicated that mechanical erosion could also play a significant role. Quantifying the rates of the different processes is challenging due to the high degree of variability encountered in both field and lab settings. To measure the rates and mechanisms controlling long-term limestone weathering, we analyse a lidar scan of the Western Wall, a Roman period edifice located in Jerusalem. Surface retreat rates in fine-grained micritic limestone blocks are found to be as much as 2 orders of magnitude higher than the average rates estimated for coarse-grained limestone blocks at the same site. In addition, in experiments that use atomic force microscopy to image dissolving micritic limestone, we show that these elevated reaction rates could be due to rapid dissolution along micron-scale grain boundaries, followed by mechanical detachment of tiny particles from the surface. Our analysis indicates that micron-scale grain detachment, rather than pure chemical dissolution, could be the dominant erosional mode for fine-grained carbonate rocks.

  11. Susceptibility of limestone petrographic features to salt weathering: a scanning electron microscopy study.

    PubMed

    Alves, Carlos; Figueiredo, Carlos; Maurício, António; Aires-Barros, Luís

    2013-10-01

    Salt weathering is a major erosive process affecting porous materials in buildings. There have been attempts to relate erosive mass loss to physical characteristics of materials, but in the case of natural stone it is necessary to consider the effect of petrographic features that are a source of heterogeneity. In this paper, we use scanning electron microscopy before and after salt weathering tests in cubic specimens of three limestone types (two grainstones and a travertine) in an attempt to built conceptual models that relate petrographic features and salt weathering susceptibility (represented by mass loss). In the grainstones, the most relevant feature in controlling salt weathering processes is the interface between micrite aggregates and sparry cement that constitute weakness surfaces and barriers to fluid migration. Given the small size of the heterogeneities in relation to the test sample dimension and their spatial distribution, the macroscopic erosive patterns are globally homogeneously distributed, affecting edges and corners. In the travertine specimens, there are macroheterogeneities related to the presence of detritic-rich portions that cause heterogeneous erosive patterns in the specimens. Petrological modeling helps to understand results of salt weathering tests, supporting field studies for natural stone selection.

  12. 46 CFR 160.072-5 - Accelerated weathering test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 6 2012-10-01 2012-10-01 false Accelerated weathering test. 160.072-5 Section 160.072-5... weathering test. (a) Condition the flag, folded to 1/16th its size or as packaged, whichever is smaller, by... less than 24 hours. (d) The flag fails the accelerated weathering test if (1) After conditioning,...

  13. 46 CFR 160.072-5 - Accelerated weathering test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 6 2013-10-01 2013-10-01 false Accelerated weathering test. 160.072-5 Section 160.072-5... weathering test. (a) Condition the flag, folded to 1/16th its size or as packaged, whichever is smaller, by... less than 24 hours. (d) The flag fails the accelerated weathering test if (1) After conditioning,...

  14. 46 CFR 160.072-5 - Accelerated weathering test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 6 2014-10-01 2014-10-01 false Accelerated weathering test. 160.072-5 Section 160.072-5... weathering test. (a) Condition the flag, folded to 1/16th its size or as packaged, whichever is smaller, by... less than 24 hours. (d) The flag fails the accelerated weathering test if (1) After conditioning,...

  15. 46 CFR 160.072-5 - Accelerated weathering test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 6 2011-10-01 2011-10-01 false Accelerated weathering test. 160.072-5 Section 160.072-5... weathering test. (a) Condition the flag, folded to 1/16th its size or as packaged, whichever is smaller, by... less than 24 hours. (d) The flag fails the accelerated weathering test if (1) After conditioning,...

  16. 46 CFR 160.072-5 - Accelerated weathering test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 6 2010-10-01 2010-10-01 false Accelerated weathering test. 160.072-5 Section 160.072-5... weathering test. (a) Condition the flag, folded to 1/16th its size or as packaged, whichever is smaller, by... less than 24 hours. (d) The flag fails the accelerated weathering test if (1) After conditioning,...

  17. Increasing shallow groundwater CO2 and limestone weathering, Konza Prairie, USA

    USGS Publications Warehouse

    Macpherson, G.L.; Roberts, J.A.; Blair, J.M.; Townsend, M.A.; Fowle, D.A.; Beisner, K.R.

    2008-01-01

    In a mid-continental North American grassland, solute concentrations in shallow, limestone-hosted groundwater and adjacent surface water cycle annually and have increased steadily over the 15-year study period, 1991-2005, inclusive. Modeled groundwater CO2, verified by measurements of recent samples, increased from 10-2.05 atm to 10-1.94 atm, about a 20% increase, from 1991 to 2005. The measured groundwater alkalinity and alkaline-earth element concentrations also increased over that time period. We propose that carbonate minerals dissolve in response to lowered pH that occurs during an annual carbonate-mineral saturation cycle. The cycle starts with low saturation during late summer and autumn when dissolved CO2 is high. As dissolved CO2 decreases in the spring and early summer, carbonates become oversaturated, but oversaturation does not exceed the threshold for precipitation. We propose that groundwater is a CO2 sink through weathering of limestone: soil-generated CO2 is transformed to alkalinity through dissolution of calcite or dolomite. The annual cycle and long-term increase in shallow groundwater CO2 is similar to, but greater than, atmospheric CO2. ?? 2008 Elsevier Ltd. All rights reserved.

  18. Efficacy of nanolime in restoration procedures of salt weathered limestone rock

    NASA Astrophysics Data System (ADS)

    Ruffolo, Silvestro A.; La Russa, Mauro F.; Aloise, Piergiorgio; Belfiore, Cristina M.; Macchia, Andrea; Pezzino, Antonino; Crisci, Gino M.

    2014-03-01

    Salt crystallisation process is one of the most powerful weathering agents in stone materials, especially in the coastal areas, where sea-spray transports large amount of salts on the stone surface. The consolidation of such degraded stone material represents a critical issue in the field of restoration of cultural heritage. In this paper, the nanolime consolidation behaviour in limestone degraded by salt crystallization has been assessed. For this purpose, a stone material taken from a Sicilian historical quarry and widely used in the eastern Sicilian Baroque architecture has been artificially degraded by the salt crystallization test. Then degraded samples have been treated with NanoRestore®, a suspension of nanolime in isopropyl alcohol. To evaluate the consolidating effectiveness, the peeling test and point load test were performed. Moreover, mercury intrusion porosimetry has been executed to evaluate the variations induced by treatment, while colorimetric measurements have been aimed to assess aesthetical issues.

  19. Salt weathering in Egyptian limestone after laboratory simulations with continuous flow of salt solutions at different temperatures

    NASA Astrophysics Data System (ADS)

    Aly, Nevin; Gomez-Heras, Miguel; Hamed, Ayman; Alvarez de Buergo, Monica

    2013-04-01

    weathering in Egyptian limestone after laboratory simulations with continuous flow of salt solutions at different temperatures Nevin Aly Mohamed (1), Miguel Gomez - Heras(2), Ayman Hamed Ahmed (1), and Monica Alvarez de Buergo(2). (1) Faculty of Pet. & Min. Engineering- Suez Canal University, Suez, Egypt, (2) Instituto de Geociencias (CSIC-UCM) Madrid. Spain. Limestone is one of the most frequent building stones in Egypt and is used since the time of ancient Egyptians and salt weathering is one of the main threats to its conservation. Most of the limestone used in historical monuments in Cairo is a biomicrite extracted from the Mid-Eocene Mokattam Group. During this work, cylindrical samples (2.4 cm diameter and approx. 4.8 cm length) were subjected, in a purpose-made simulation chamber, to simulated laboratory weathering tests with fixed salt concentration (10% weight NaCl solution), at different temperatures, which were kept constant throughout each test (10, 20, 30, 40 oC). During each test, salt solutions flowed continuously imbibing samples by capilarity. Humidity within the simulation chamber was reduced using silica gel to keep it low and constant to increase evaporation rate. Temperature, humidity inside the simulation chamber and samples weight were digitally monitored during each test. Results show the advantages of the proposed experimental methodology using a continuous flow of salt solutions and shed light on the effect of temperature on the dynamics of salt crystallization on and within samples. Research funded by mission sector of high education ministry, Egypt and Geomateriales S2009/MAT-1629.

  20. Neutron radiography and X-ray computed tomography for quantifying weathering and water uptake processes inside porous limestone used as building material

    SciTech Connect

    Dewanckele, J.; De Kock, T.; Fronteau, G.; Derluyn, H.; Vontobel, P.; Dierick, M.; Van Hoorebeke, L.; Jacobs, P.; Cnudde, V.

    2014-02-15

    Euville and Savonnières limestones were weathered by acid test and this resulted in the formation of a gypsum crust. In order to characterize the crystallization pattern and the evolution of the pore structure below the crust, a combination of high resolution X-ray computed tomography and SEM–EDS was used. A time lapse sequence of the changing pore structure in both stones was obtained and afterwards quantified by using image analysis. The difference in weathering of both stones by the same process could be explained by the underlying microstructure and texture. Because water and moisture play a crucial role in the weathering processes, water uptake in weathered and non-weathered samples was characterized based on neutron radiography. In this way the water uptake was both visualized and quantified in function of the height of the sample and in function of time. In general, the formation of a gypsum crust on limestone slows down the initial water uptake in the materials. - Highlights: • Time lapse sequence in 3D of changing pore structures inside limestone • A combination of X-ray CT, SEM and neutron radiography was used. • Quantification of water content in function of time, height and weathering • Characterization of weathering processes due to gypsum crystallization.

  1. Accelerating Climate and Weather Simulations through Hybrid Computing

    NASA Technical Reports Server (NTRS)

    Zhou, Shujia; Cruz, Carlos; Duffy, Daniel; Tucker, Robert; Purcell, Mark

    2011-01-01

    Unconventional multi- and many-core processors (e.g. IBM (R) Cell B.E.(TM) and NVIDIA (R) GPU) have emerged as effective accelerators in trial climate and weather simulations. Yet these climate and weather models typically run on parallel computers with conventional processors (e.g. Intel, AMD, and IBM) using Message Passing Interface. To address challenges involved in efficiently and easily connecting accelerators to parallel computers, we investigated using IBM's Dynamic Application Virtualization (TM) (IBM DAV) software in a prototype hybrid computing system with representative climate and weather model components. The hybrid system comprises two Intel blades and two IBM QS22 Cell B.E. blades, connected with both InfiniBand(R) (IB) and 1-Gigabit Ethernet. The system significantly accelerates a solar radiation model component by offloading compute-intensive calculations to the Cell blades. Systematic tests show that IBM DAV can seamlessly offload compute-intensive calculations from Intel blades to Cell B.E. blades in a scalable, load-balanced manner. However, noticeable communication overhead was observed, mainly due to IP over the IB protocol. Full utilization of IB Sockets Direct Protocol and the lower latency production version of IBM DAV will reduce this overhead.

  2. Durability of anti-graffiti coatings on stone: natural vs accelerated weathering.

    PubMed

    Carmona-Quiroga, Paula M; Jacobs, Robert M J; Martínez-Ramírez, Sagrario; Viles, Heather A

    2017-01-01

    Extending the use of novel anti-graffiti coatings to built heritage could be of particular interest providing the treatments are efficient enough in facilitating graffiti removal and long-lasting to maintain their protective properties without interfering with the durability of the substrates. However, studies of the durability of these coatings are scarce and have been mainly carried out under accelerated weathering conditions, the most common practice for assessing the durability of materials but one that does not reproduce accurately natural working conditions. The present study aimed to assess the durability of the anti-graffiti protection afforded by two anti-graffiti treatments (a water dispersion of polyurethane with a perfluoropolyether backbone and a water based crystalline micro wax) on Portland limestone and Woodkirk sandstone after 1 year of outdoor exposure in the South of England with periodic painting and cleaning episodes taking place. A parallel study under artificial weathering conditions in a QUV chamber for 2000 hours was also carried out. Changes to the coatings were assessed by measuring colour, gloss, water-repellency, roughness and microstructure, the latter through micro-Raman and optical microscope observations, periodically during the experiments. The results show that both anti-graffiti treatments deteriorated under both artificial and natural weathering conditions. For the polyurethane based anti-graffiti treatment, artificial ageing produced more deterioration than 1 year of outdoor exposure in the south of England due to loss of adhesion from the stones, whereas for micro wax coating there were no substantial differences between the two types of weathering.

  3. Durability of anti-graffiti coatings on stone: natural vs accelerated weathering

    PubMed Central

    Jacobs, Robert M. J.; Martínez-Ramírez, Sagrario; Viles, Heather A.

    2017-01-01

    Extending the use of novel anti-graffiti coatings to built heritage could be of particular interest providing the treatments are efficient enough in facilitating graffiti removal and long-lasting to maintain their protective properties without interfering with the durability of the substrates. However, studies of the durability of these coatings are scarce and have been mainly carried out under accelerated weathering conditions, the most common practice for assessing the durability of materials but one that does not reproduce accurately natural working conditions. The present study aimed to assess the durability of the anti-graffiti protection afforded by two anti-graffiti treatments (a water dispersion of polyurethane with a perfluoropolyether backbone and a water based crystalline micro wax) on Portland limestone and Woodkirk sandstone after 1 year of outdoor exposure in the South of England with periodic painting and cleaning episodes taking place. A parallel study under artificial weathering conditions in a QUV chamber for 2000 hours was also carried out. Changes to the coatings were assessed by measuring colour, gloss, water-repellency, roughness and microstructure, the latter through micro-Raman and optical microscope observations, periodically during the experiments. The results show that both anti-graffiti treatments deteriorated under both artificial and natural weathering conditions. For the polyurethane based anti-graffiti treatment, artificial ageing produced more deterioration than 1 year of outdoor exposure in the south of England due to loss of adhesion from the stones, whereas for micro wax coating there were no substantial differences between the two types of weathering. PMID:28231301

  4. Chemical alteration of limestone and marble samples exposed to acid rain and weathering in the eastern United States, 1984--1988

    SciTech Connect

    Reimann, K.J.

    1991-06-01

    In a long-term program that began in 1984, limestone and marble briquettes have been exposed to both anthropogenic acid deposition and natural weathering of four field sites in the eastern United States. Similar tests began at an Ohio site in 1986. Effects of exposure on the briquettes and other materials at the sites are evaluated periodically by several federal agencies cooperating in the National Acid Precipitation Assessment Program (NAPAP). A primary contribution of Argonne National Laboratory to the NAPAP has been chemical analysis to determine changes in the samples caused by exposure to the environment. Wet chemical analysis was used to detect sulfates, nitrates, fluorides, chlorides, and a series of metal cations in sequential layers of stone removed from the briquettes after field exposure. Results from the first four years of the program indicate that rinsing by rain keeps skyward-facing stone relatively clean of reaction products, especially sulfate, the most abundant product. On groundward-facing samples, sulfate concentrations increased linearly with exposure time, and values were proportional to atmospheric SO{sub 2} concentrations at the site. Sulfate concentrations in groundward samples were much higher in limestone than in marble, because of the greater porosity of the limestone. A steep sulfate gradient was seen in both sample types from the surface to the interior. On skyward surfaces, material losses per rain event due to complete dissolution of accumulated sulfates were approximately equal to concentrations measured in runoff. Preexposed limestone samples had sulfate accumulations deep in their interiors, while fresh, unexposed limestone did not. No substantial changes in cation accumulations wee detected in either limestone or marble.

  5. Chemical depth profiling of photovoltaic backsheets after accelerated laboratory weathering

    NASA Astrophysics Data System (ADS)

    Lin, Chiao-Chi; Krommenhoek, Peter J.; Watson, Stephanie S.; Gu, Xiaohong

    2014-10-01

    Polymeric multilayer backsheets provide protection for the backside of photovoltaic (PV) module from the damage of moisture and ultraviolet (UV). Due to the nature of multilayer films, certain material property characterization of a backsheet could only be studied by examining its cross-section parallel to the thickness direction of the film. In this study, commercial PPE (polyethylene terephthalate (PET)/PET/ethylene vinyl acetate (EVA)) backsheet films were aged on the NIST (National Institute of Standards and Technology) SPHERE (Simulated Photodegradation via High Energy Radiant Exposure) with UV irradiance at 170 W/m2 (300 nm to 400 nm) under accelerated weathering conditions of 85°C and two relative humidity (R.H.) levels of 5% (low) and 60% (high). Cryo-microtomy was used to obtain cross-sectional PPE samples with a flat surface parallel to the thickness direction, and chemical depth profiling of multilayers was conducted by Raman microscopic mapping. Atomic force microscopy with peak force tapping mode was used complementarily for cross-sectional imaging. The results revealed that the PPE backsheet films were comprised of five main layers, including pigmented-PET, core PET, inner EVA, pigmented-EVA and outer EVA, along with their interfacial regions and two adhesive layers. UV and moisture degradation on the outer pigmented PET layer was clearly observed; while the damage on the core PET layer was less significance, indicating that the outer pigmented PET layer effectively reduced the damage from UV. In high R.H. exposure, both adhesive layers were severely deteriorated. It was found that the EVA layers were susceptible to moisture at elevated temperature, especially for the pigmented-EVA. Based on the results of accelerated weathering, this depth profiling study brings new understanding to the mechanisms of failure observed in polymeric multilayer backsheets during field exposure.

  6. Weatherization and Intergovernmental Program - Accelerating Adoption of Energy Efficiency and Renewable Energy

    SciTech Connect

    2010-06-01

    The DOE/EERE Weatherization and Intergovernmental Program (WIP) increases awareness and accelerates adoption of practices and technologies that cost-effectively increase energy efficiency, the use of renewable energy, and oil displacement.

  7. Dissolution rates of subsoil limestone in a doline on the Akiyoshi-dai Plateau, Japan: An approach from a weathering experiment, hydrological observations, and electrical resistivity tomography

    NASA Astrophysics Data System (ADS)

    Akiyama, Sanae; Hattanji, Tsuyoshi; Matsushi, Yuki; Matsukura, Yukinori

    2015-10-01

    This study aims at estimating the controlling factors for the denudation rates of limestone, which often forms solution dolines on karst tablelands. Our approaches include (1) electrical resistivity tomography (ERT) to reveal shallow subsurface structures and hydrological settings, (2) automated monitoring of volumetric water content in soil profiles and manual measurements of subsurface CO2 concentrations and soil water chemistry, and (3) a field weathering experiment using limestone tablets with the micro-weight loss technique for determining current denudation rates. The field experiment and monitoring were carried out over 768 days from 2009-2011 at four sites with varying topographic and hydrological conditions along the sideslope of a doline on the Akiyoshi-dai karst plateau in SW-Japan. The installation depths of the limestone tablets were 15 cm or 50 cm below the slope surface. The soil moisture conditions varied site by site. Water-saturated conditions continued for 40-50% of the whole experimental period at 50-cm depth of upper and middle sites, while only 0-10% of the experimental period was water-saturated at the other sites. Chemical analysis revealed that the soil water was chemically unsaturated with calcite for all the sites. Spatial differences in concentrations of CO2 in soil pore air were statistically less significant. The denudation rates of the buried limestone tablets were 17.7-21.9 mg cm- 2 a- 1 at the upper and middle slopes, where the soil was water-saturated for a long time after precipitation. The lowest denudation of 3.9 mg cm- 2 a- 1 was observed on lower slopes where soil was not capable of maintaining water at a near saturation level even after precipitation. Statistical analysis revealed that the denudation rates of the tablets were strongly controlled by the duration for which soil pores were saturated by water (the conditions defined here are degrees of water saturation greater than 97%). Electrical resistivity tomography

  8. Real-Time and Accelerated Solar Weathering of Commercial PV Modules: Preprint

    SciTech Connect

    Osterwald, C. R.; Pruett, J.; Myers, D. R.; Rummel, S.; Anderberg, A.; Ottoson, L.; Basso, T.

    2001-10-01

    Presented at the 2001 NCPV Program Review Meeting: We report the observed degradation in 6 different types of PV modules as a function of total UV exposure and give a number of recommendations for future weathering tests. Since 1997, using existing ASTM standards for weathering of materials, we have been conducting a solar weathering program on a group of six different types of photovoltaic (PV) modules. The methods used include real-time outdoor, accelerated outdoor, and accelerated indoor weathering. We have employed the technique specified in these standards that quantifies exposure totals by the time integral of the ultraviolet (UV) irradiance. In this paper, we report the observed degradation in the test modules as a function of total UV exposure, and give a number of recommendations for future weathering tests that resulted from our first attempt at a formal test program.

  9. Accelerating the carbon cycle: the ethics of enhanced weathering.

    PubMed

    Lawford-Smith, H; Currie, A

    2017-04-01

    Enhanced weathering, in comparison to other geoengineering measures, creates the possibility of a reduced cost, reduced impact way of decreasing atmospheric carbon, with positive knock-on effects such as decreased oceanic acidity. We argue that ethical concerns have a place alongside empirical, political and social factors as we consider how to best respond to the critical challenge that anthropogenic climate change poses. We review these concerns, considering the ethical issues that arise (or would arise) in the large-scale deployment of enhanced weathering. We discuss post-implementation scenarios, failures of collective action, the distribution of risk and externalities and redress for damage. We also discuss issues surrounding 'dirty hands' (taking conventionally immoral action to avoid having to take action that is even worse), whether enhanced weathering research might present a moral hazard, the importance of international governance and the notion that the implementation of large-scale enhanced weathering would reveal problematic hubris. Ethics and scientific research interrelate in complex ways: some ethical considerations caution against research and implementation, while others encourage them. Indeed, the ethical perspective encourages us to think more carefully about how, and what types of, geoengineering should be researched and implemented.

  10. Effect of accelerated weathering on surface chemistry of modified wood

    NASA Astrophysics Data System (ADS)

    Temiz, Ali; Terziev, Nasko; Eikenes, Morten; Hafren, Jonas

    2007-04-01

    In this study, the effects of UV-light irradiation and water spray on colour and surface chemistry of scots pine sapwood samples were investigated. The specimens were treated with chromated copper arsenate (CCA), a metal-free propiconazol-based formulation, chitosan, furfuryl alcohol and linseed and tall oils. The weathering experiment was performed by cycles of 2 h UV-light irradiation followed by water spray for 18 min. The changes at the surface of the weathered samples were characterised by Fourier transform infrared spectroscopy (FT-IR); colour characterizations were performed by measuring CIELab parameters. The results show that all treatment methods except chitosan treatment provided lower colour changes than the control groups after 800 h exposure in weathering test cycle, but differences between chitosan and control were also small. The lowest colour changes were found on linseed oil (full cell process) and CCA treated wood. FT-IR results show that oil treatment (linseed and tall oil) decreased the intensities of a lignin specific peak (1500-1515 cm -1). Absorption band changes at 1630-1660 cm -1 were reduced by all treatments.

  11. Exposure of Polymeric Glazing Materials Using NREL's Ultra-Accelerated Weathering System (UAWS)

    SciTech Connect

    Bingham, C.; Jorgensen, G.; Wylie, A.

    2010-01-01

    NREL's Ultra-Accelerated Weathering System (UAWS) selectively reflects and concentrates natural sunlight ultraviolet irradiance below 475 nm onto exposed samples to provide accelerated weathering of materials while keeping samples within realistic temperature limits. This paper will explain the design and implementation of the UAWS which allow it to simulate the effect of years of weathering in weeks of exposure. Exposure chamber design and instrumentation will be discussed for both a prototype UAWS used to test glazing samples as well as a commercial version of UAWS. Candidate polymeric glazing materials have been subjected to accelerated exposure testing at a light intensity level of up to 50 UV suns for an equivalent outdoor exposure in Miami, FL exceeding 15 years. Samples include an impact modified acrylic, fiberglass, and polycarbonate having several thin UV-screening coatings. Concurrent exposure is carried out for identical sample sets at two different temperatures to allow thermal effects to be quantified along with resistance to UV.

  12. Effect of Reprocessing and Accelerated Weathering on Impact-Modified Recycled Blend

    NASA Astrophysics Data System (ADS)

    Ramesh, V.; Mohanty, Smita; Biswal, Manoranjan; Nayak, Sanjay K.

    2015-12-01

    Recovery of recycled polycarbonate, acrylonitrile butadiene styrene, high-impact polystyrene, and its blends from waste electrical and electronic equipment plastics products properties were enhanced by the addition of virgin polycarbonate and impact modifier. The optimized blend formulation was processed through five cycles, at processing temperature, 220-240 °C and accelerated weathering up to 700 h. Moreover, the effect of reprocessing and accelerated weathering in the physical properties of the modified blends was investigated by mechanical, thermal, rheological, and morphological studies. The results show that in each reprocessing cycle, the tensile strength and impact strength decreased significantly and the similar behavior has been observed from accelerated weathering. Subsequently, the viscosity decreases and this decrease becomes the effect of thermal and photo-oxidative degradation. This can be correlated with FTIR analysis.

  13. The NREL Outdoor Accelerated-Weathering Tracking System Photovoltaic Module Exposure Results

    SciTech Connect

    Basso, T. S.

    2000-01-01

    Status results are presented for the Outdoor Accelerated-Weathering Tracking System (OATS) first study on photovoltaic (PV) modules. Studies began in November 1997 on pairs of commercially available crystalline silicon and amorphous silicon (a-Si) PV modules kept at constant resistive load.

  14. Analysis on weathering characteristics of volcanic rocks in Dokdo, Korea based on accelerated weatehring experiments

    NASA Astrophysics Data System (ADS)

    Woo, Ik; Song, Won-Kyong; Kim, Bok-Chul; Kang, Jinseok

    2010-05-01

    Dokdo consists of small volcanic islands located in the southern part of the East Sea. Accelerated weathering tests was performed to examine the physico-mechanical characteristics of volcanic rocks in Dokdo. Rock core specimens of trachyandesite, andesitic dyke and ash tuff were prepared, and double soxhlet extractors(DSE) and peristatic pumps were used for accelerating the weathering processes. The DSE was designed to perform cyclic leaching tests for rock core specimen using distilled water at seventy degrees centigrade. The core specimens which are classified according to pre-test weathering grades placed in the lower part of the DSE, and periodically exposed to hot distilled water at every ninety minutes. On the other hand the peristatic pumps were utilized to induce leaching by distilled or brine water at normal temperature. The physico-mechanical property changes including rock surface appearance, microscopic structure and rock strength were analyzed with the results obtained from both experiments performed for 120 days. The conducted research in this study have shown that the methodologies of artificial weathering experiments have strong capability to understand the weathering characteristics of the rocks effectively.

  15. Limestone Caverns

    ERIC Educational Resources Information Center

    Powell, Richard L.

    1970-01-01

    Describes the origin of limestone caverns, using Mammoth Cave as an example, with particular reference to the importance of groundwater information of caverns, the present condition of groundwater, and how caverns develop within fluctuating groundwater zones. (BR)

  16. Weather.

    ERIC Educational Resources Information Center

    Ruth, Amy, Ed.

    1996-01-01

    This theme issue of "The Goldfinch" focuses on weather in Iowa and weather lore. The bulletin contains historical articles, fiction, activities, and maps. The table of contents lists: (1) "Wild Rosie's Map"; (2) "History Mystery"; (3) "Iowa's Weather History"; (4) "Weather Wonders"; (6)…

  17. Limestone geomorphology

    SciTech Connect

    Trudgill, S.

    1985-01-01

    This book focuses on recent work on geomorphological processes and relates them to established theories of landform development. Special attention is paid to soil processes, marine geomorphology, chemical processes and future work on process-form relationships in the context of dated sequences of cave deposits. There are discussions of limestone landforms and other carbonate rocks, caves, hydrological networks, features of karst, morphometry, and coastal landforms and solution chemistry of limestones.

  18. Analysis of induced radionuclides in low-activation concrete (limestone concrete) using the 12 GeV proton synchrotron accelerator facility at KEK.

    PubMed

    Saito, K; Tanosaki, T; Fujii, H; Miura, T

    2005-01-01

    22Na is one of the long-lived radionuclides induced in shielding concrete of a beam-line tunnel of a high-energy particle accelerator facility and poses a problem of radiation wastes at the decommissioning of the facility. In order to estimate the 22Na concentration induced in shielding concrete, chemical reagents such as NaHCO3, MgO, Al203, SiO2 and CaCO3 were irradiated at several locations in the beam-line tunnel of the 12 GeV proton synchrotron accelerator at KEK, and the 22Na concentrations induced in those chemical reagents were measured. Low-activation concrete made up of limestone aggregates was also irradiated by secondary particles in the beam-line tunnel and the long-lived radionuclide, such as 22Na, concentrations induced in the concrete were measured. It was confirmed that 22Na concentrations induced in Mg, Al, Si and Ca were lower than that in Na, and that 22Na concentrations induced in the low-activation concrete was lower than those induced in ordinary concrete made up of sandstone aggregates.

  19. Scaling on a limestone flooring

    NASA Astrophysics Data System (ADS)

    Carmona-Quiroga, P. M.; Blanco-Varela, M. T.; Martínez-Ramírez, S.

    2012-04-01

    Natural stone can be use on nearly every surface, inside and outside buildings, but decay is more commonly reported from the ones exposed to outdoor aggressively conditions. This study instead, is an example of limestone weathering of uncertain origin in the interior of a residential building. The stone, used as flooring, started to exhibit loss of material in the form of scaling. These damages were observed before the building, localized in the South of Spain (Málaga), was inhabited. Moreover, according to the company the limestone satisfies the following European standards UNE-EN 1341: 2002, UNE-EN 1343: 2003; UNE-EN 12058: 2004 for floorings. Under these circumstances the main objective of this study was to assess the causes of this phenomenon. For this reason the composition of the mortar was determined and the stone was characterized from a mineralogical and petrological point of view. The last material, which is a fossiliferous limestone from Egypt with natural fissure lines, is mainly composed of calcite, being quartz, kaolinite and apatite minor phases. Moreover, under different spectroscopic and microscopic techniques (FTIR, micro-Raman, SEM-EDX, etc) samples of the weathered, taken directly from the buildings, and unweathered limestone tiles were examined and a new mineralogical phase, trona, was identified at scaled areas which are connected with the natural veins of the stone. In fact, through BSE-mapping the presence of sodium has been detected in these veins. This soluble sodium carbonate would was dissolved in the natural waters from which limestone was precipitated and would migrate with the ascendant capilar humidity and crystallized near the surface of the stone starting the scaling phenomenon which in historic masonry could be very damaging. Therefore, the weathering of the limestone would be related with the hygroscopic behaviour of this salt, but not with the constructive methods used. This makes the limestone unable to be used on restoration

  20. Surface degradation of CeO2 stabilized acrylic polyurethane coated thermally treated jack pine during accelerated weathering

    NASA Astrophysics Data System (ADS)

    Saha, Sudeshna; Kocaefe, Duygu; Boluk, Yaman; Pichette, Andre

    2013-07-01

    The thermally treated wood is a new value-added product and is very important for the diversification of forestry products. It drew the attention of consumers due to its attractive dark brown color. However, it loses its color when exposed to outside environment. Therefore, development of a protective coating for this value added product is necessary. In the present study, the efficiency of CeO2 nano particles alone or in combination with lignin stabilizer and/or bark extracts in acrylic polyurethane polymer was investigated by performing an accelerated weathering test. The color measurement results after accelerated weathering demonstrated that the coating containing CeO2 nano particles was the most effective whereas visual assessment suggested the coating containing CeO2 nano particles and lignin stabilizer as the most effective coating. The surface polarity changed for all the coatings during weathering and increase in contact angle after weathering suggested cross linking and reorientation of the polymer chain during weathering. The surface chemistry altered during weathering was evaluated by ATR-FTIR analysis. It suggested formation of different carbonyl byproducts during weathering. The chain scission reactions of the urethane linkages were not found to be significant during weathering.

  1. Copper leaching of MSWI bottom ash co-disposed with refuse: effect of short-term accelerated weathering.

    PubMed

    Su, Lianghu; Guo, Guangzhai; Shi, Xinlong; Zuo, Minyu; Niu, Dongjie; Zhao, Aihua; Zhao, Youcai

    2013-06-01

    Co-disposal of refuse with municipal solid waste incinerator (MSWI) bottom ash (IBA) either multi-layered as landfill cover or mixed with refuse could pose additional risk to the environment because of enhanced leaching of heavy metals, especially Cu. This study applied short-term accelerated weathering to IBA, and monitored the mineralogical and chemical properties of IBA during the weathering process. Cu extractability of the weathered IBA was then evaluated using standard leaching protocols (i.e. SPLP and TCLP) and co-disposal leaching procedure. The results showed that weathering had little or no beneficial effect on Cu leaching in SPLP and TCLP, which can be explained by the adsorption and complexation of Cu with DOM. However, the Cu leaching of weathered IBA was reduced significantly when situated in fresh simulated landfill leachate. This was attributed to weakening Cu complexation with fulvic acid or hydrophilic fractions and/or intensifying Cu absorption to neoformed hydr(oxide) minerals in weathered IBA. The amount of total leaching Cu and Cu in free or labile complex fraction (the fraction with the highest mobility and bio-toxicity) of the 408-h weathered IBA were remarkably decreased by 86.3% and 97.6% in the 15-day co-disposal leaching test. Accelerated weathering of IBA may be an effective pretreatment method to decrease Cu leaching prior to its co-disposal with refuse.

  2. Electrochemical acceleration of chemical weathering as an energetically feasible approach to mitigating anthropogenic climate change.

    PubMed

    House, Kurt Zenz; House, Christopher H; Schrag, Daniel P; Aziz, Michael J

    2007-12-15

    We describe an approach to CO2 capture and storage from the atmosphere that involves enhancing the solubility of CO2 in the ocean by a process equivalent to the natural silicate weathering reaction. HCl is electrochemically removed from the ocean and neutralized through reaction with silicate rocks. The increase in ocean alkalinity resulting from the removal of HCI causes atmospheric CO2 to dissolve into the ocean where it will be stored primarily as HCO3- without further acidifying the ocean. On timescales of hundreds of years or longer, some of the additional alkalinity will likely lead to precipitation or enhanced preservation of CaCO3, resulting in the permanent storage of the associated carbon, and the return of an equal amount of carbon to the atmosphere. Whereas the natural silicate weathering process is effected primarily by carbonic acid, the engineered process accelerates the weathering kinetics to industrial rates by replacing this weak acid with HCI. In the thermodynamic limit--and with the appropriate silicate rocks--the overall reaction is spontaneous. A range of efficiency scenarios indicates that the process should require 100-400 kJ of work per mol of CO2 captured and stored for relevant timescales. The process can be powered from stranded energy sources too remote to be useful for the direct needs of population centers. It may also be useful on a regional scale for protection of coral reefs from further ocean acidification. Application of this technology may involve neutralizing the alkaline solution that is coproduced with HCI with CO2 from a point source or from the atmosphere prior to being returned to the ocean.

  3. Accelerated Weathering of Fluidized Bed Steam Reformation Material Under Hydraulically Unsaturated Conditions

    SciTech Connect

    Pierce, Eric M.

    2007-09-16

    To predict the long-term fate of low- and high-level waste forms in the subsurface over geologic time scales, it is important to understand the behavior of the corroding waste forms under conditions the mimic to the open flow and transport properties of a subsurface repository. Fluidized bed steam reformation (FBSR), a supplemental treatment technology option, is being considered as a waste form for the immobilization of low-activity tank waste. To obtain the fundamental information needed to evaluate the behavior of the FBSR waste form under repository relevant conditions and to monitor the long-term behavior of this material, an accelerated weathering experiment is being conducted with the pressurized unsaturated flow (PUF) apparatus. Unlike other accelerated weathering test methods (product consistency test, vapor hydration test, and drip test), PUF experiments are conducted under hydraulically unsaturated conditions. These experiments are unique because they mimic the vadose zone environment and allow the corroding waste form to achieve its final reaction state. Results from this on-going experiment suggest the volumetric water content varied as a function of time and reached steady state after 160 days of testing. Unlike the volumetric water content, periodic excursions in the solution pH and electrical conductivity have been occurring consistently during the test. Release of elements from the column illustrates a general trend of decreasing concentration with increasing reaction time. Normalized concentrations of K, Na, P, Re (a chemical analogue for 99Tc), and S are as much as 1 × 104 times greater than Al, Cr, Si, and Ti. After more than 600 days of testing, the solution chemistry data collected to-date illustrate the importance of understanding the long-term behavior of the FBSR product under conditions that mimic the open flow and transport properties of a subsurface repository.

  4. The Weathering of Plastics Materials in the Tropics. 6. The Further Evaluation of a Solar Radiation Concentrating Device (EMMA) as a Means of Accelerating the Weathering of Plastics

    DTIC Science & Technology

    1981-01-01

    in the Tropics: Part 6 Further Evaluation of a Solar Radiation Concentrating Device (EMMA) as a means of Accelerating the Weathering of Plastics by...specimens were cut using a cutter meeting the requirements of BS 903 Part A2 (Type E). 2.3 Polyacetal Specimens The polyacetal specimens were marhined...52 weeks. These periods were based, in part , on the previous trial results and also in the expectation that the specimens on static exposure would

  5. Climate-change effects on soils: Accelerated weathering, soil carbon and elemental cycling

    SciTech Connect

    Qafoku, Nikolla

    2015-04-01

    Climate change [i.e., high atmospheric carbon dioxide (CO2) concentrations (≥400 ppm); increasing air temperatures (2-4°C or greater); significant and/or abrupt changes in daily, seasonal, and inter-annual temperature; changes in the wet/dry cycles; intensive rainfall and/or heavy storms; extended periods of drought; extreme frost; heat waves and increased fire frequency] is and will significantly affect soil properties and fertility, water resources, food quantity and quality, and environmental quality. Biotic processes that consume atmospheric CO2, and create organic carbon (C) that is either reprocessed to CO2 or stored in soils are the subject of active current investigations, with great concern over the influence of climate change. In addition, abiotic C cycling and its influence on the inorganic C pool in soils is a fundamental global process in which acidic atmospheric CO2 participates in the weathering of carbonate and silicate minerals, ultimately delivering bicarbonate and Ca2+ or other cations that precipitate in the form of carbonates in soils or are transported to the rivers, lakes, and oceans. Soil responses to climate change will be complex, and there are many uncertainties and unresolved issues. The objective of the review is to initiate and further stimulate a discussion about some important and challenging aspects of climate-change effects on soils, such as accelerated weathering of soil minerals and resulting C and elemental fluxes in and out of soils, soil/geo-engineering methods used to increase C sequestration in soils, soil organic matter (SOM) protection, transformation and mineralization, and SOM temperature sensitivity. This review reports recent discoveries, identifies key research needs, and highlights opportunities offered by the climate-change effects on soils.

  6. Characterization of surface chemistry and crystallization behavior of polypropylene composites reinforced with wood flour, cellulose, and lignin during accelerated weathering

    NASA Astrophysics Data System (ADS)

    Peng, Yao; Liu, Ru; Cao, Jinzhen

    2015-03-01

    In this study, six groups of polypropylene composites reinforced with wood flour (WF), cellulose, and lignin at different loading levels were exposed in a QUV accelerated weathering tester for a total duration of 960 h. The changes in surface morphology, chemistry, and thermal properties of weathered samples were characterized by atomic force microscope (AFM), attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and differential scanning calorimetric (DSC), respectively. The flexural properties of all samples were tested after different durations of weathering. The results showed that: (1) the surface roughness of all samples increased after weathering; (2) composites containing lignin showed less loss of flexural strength and modulus and less roughness on weathered surface compared with lignin-free composites, indicating the functions of stabilization and antioxidation of lignin; (3) the crystallinity of PP increased in all weathered samples due to chain scissions and recrystallization; (4) ATR-FTIR and XPS analyses demonstrated in detail that significant changes occurred in surface chemistry, accompanied by the photodegradation and photo-oxidation of lignin and cellulose with prolonged weathering time.

  7. Microwave Radiometer Technology Acceleration Mission (MiRaTA): Advancing Weather Remote Sensing with Nanosatellites

    NASA Astrophysics Data System (ADS)

    Cahoy, K.; Blackwell, W. J.; Bishop, R. L.; Erickson, N.; Fish, C. S.; Neilsen, T. L.; Stromberg, E. M.; Bardeen, J.; Dave, P.; Marinan, A.; Marlow, W.; Kingsbury, R.; Kennedy, A.; Byrne, J. M.; Peters, E.; Allen, G.; Burianek, D.; Busse, F.; Elliott, D.; Galbraith, C.; Leslie, V. V.; Osaretin, I.; Shields, M.; Thompson, E.; Toher, D.; DiLiberto, M.

    2014-12-01

    The Microwave Radiometer Technology Acceleration (MiRaTA) is a 3U CubeSat mission sponsored by the NASA Earth Science Technology Office (ESTO). Microwave radiometer measurements and GPS radio occultation (GPSRO) measurements of all-weather temperature and humidity provide key contributions toward improved weather forecasting. The MiRaTA mission will validate new technologies in both passive microwave radiometry and GPS radio occultation: (1) new ultra-compact and low-power technology for multi-channel and multi-band passive microwave radiometers, and (2) new GPS receiver and patch antenna array technology for GPS radio occultation retrieval of both temperature-pressure profiles in the atmosphere and electron density profiles in the ionosphere. In addition, MiRaTA will test (3) a new approach to spaceborne microwave radiometer calibration using adjacent GPSRO measurements. The radiometer measurement quality can be substantially improved relative to present systems through the use of proximal GPSRO measurements as a calibration standard for radiometric observations, reducing and perhaps eliminating the need for costly and complex internal calibration targets. MiRaTA will execute occasional pitch-up maneuvers so that the radiometer and GPSRO observations sound overlapping volumes of atmosphere through the Earth's limb. To validate system performance, observations from both microwave radiometer (MWR) and GPSRO instruments will be compared to radiosondes, global high-resolution analysis fields, other satellite observations, and to each other using radiative transfer models. Both the radiometer and GPSRO payloads, currently at TRL5 but to be advanced to TRL7 at mission conclusion, can be accommodated in a single 3U CubeSat. The current plan is to launch from an International Space Station (ISS) orbit at ~400 km altitude and 52° inclination for low-cost validation over a ~90-day mission to fly in 2016. MiRaTA will demonstrate high fidelity, well-calibrated radiometric

  8. Limestone compaction: an enigma

    USGS Publications Warehouse

    Shinn, Eugene A.; Halley, Robert B.; Hudson, J. Harold; Lidz, Barbara H.

    1977-01-01

    Compression of an undisturbed carbonate sediment core under a pressure of 556 kg/cm2 produced a “rock” with sedimentary structures similar to typical ancient fine-grained limestones. Surprisingly, shells, foraminifera, and other fossils were not noticeably crushed, which indicates that absence of crushed fossils in ancient limestones can no longer be considered evidence that limestones do not compact.

  9. The NREL Outdoor Accelerated-weathering Tracking System and Photovoltaic Module Exposure Results

    SciTech Connect

    Basso, T. S.

    1998-10-31

    This paper describes the Outdoor Accelerated-weathering Tracking System (OATS) and interim results for the first OATS study on photovoltaic (PV) modules. With two test planes measuring 1.52 x 1.83 m, OATS provides a unique solar-concentrating exposure capability. Test sample temperatures are moderated by air blowers. Water spray capability exists for wetting samples. The OATS two-axis tracker points to the sun using software calculations. Non-imaging aluminum reflectors give a nominal clear-sky optical concentration ratio of three. Field-qualification measurements in the test plane under reflector conditions showed its relative irradiance non-uniformity was '' 15% for a clear-sky summer day with '' 75 mm as the smallest distance for that non-uniformity. Exposure studies began in November 1997 on seven pairs of commercially available ribbon silicon, crystalline silicon and amorphous silicon PV modules kept at constant resistive load. The modules were periodically removed from OATS for visual inspection and solar simulator performance measurements. There were no module failures. This PV module study is ongoing and later results will be compared to other testing techniques. Through July 1998, the modules under reflector conditions received 392 MJ/m2 of total ultraviolet (TUV) exposure. That was 2.07 times the TUV exposure compared to a south-facing fixed array tilted 40{sup o} up from horizontal at NREL. Similarly, the modules in the test plane under the covered reflectors received 1.04 times the fixed array TUV exposure. For the test plane under the covered reflectors there was a loss of 13% TUV exposure attributed to the reflectors blocking some of the diffuse-sky UV light. Also through July 1998, the OATS sunlight availability measured 95% compared to the cumulative global normal exposure at the NREL Solar Radiation Research Laboratory (SRRL). The OATS sunlight availability losses included downtime when the PV modules were removed, and when there were OAT S

  10. The NREL outdoor accelerated-weathering tracking system and photovoltaic module exposure results

    SciTech Connect

    Basso, T.S.

    1999-03-01

    This paper describes the Outdoor Accelerated-weathering Tracking System (OATS) and interim results for the first OATS study on photovoltaic (PV) modules. With two test planes measuring 1.52{times}1.83&hthinsp;m, OATS provides a unique solar-concentrating exposure capability. Test sample temperatures are moderated by air blowers. Water spray capability exists for wetting samples. The OATS two-axis tracker points to the sun using software calculations. Non-imaging aluminum reflectors give a nominal clear-sky optical concentration ratio of three. Field-qualification measurements in the test plane under reflector conditions showed its relative irradiance non-uniformity was {plus_minus}15{percent} for a clear-sky summer day with {plus_minus} 75 mm as the smallest distance for that non-uniformity. Exposure studies began in November 1997 on seven pairs of commercially available ribbon silicon, crystalline silicon and amorphous silicon PV modules kept at constant resistive load. The modules were periodically removed from OATS for visual inspection and solar simulator performance measurements. There were no module failures. This PV module study is ongoing and later results will be compared to other testing techniques. Through July 1998, the modules under reflector conditions received 392 MJ/m{sup 2} of total ultraviolet (TUV) exposure. That was 2.07 times the TUV exposure compared to a south-facing fixed array tilted 40{degree} up from horizontal at NREL. Similarly, the modules in the test plane under the covered reflectors received 1.04 times the fixed array TUV exposure. For the test plane under the covered reflectors there was a loss of 13{percent} TUV exposure attributed to the reflectors blocking some of the diffuse-sky UV light. Also through July 1998, the OATS sunlight availability measured 95{percent} compared to the cumulative global normal exposure at the NREL Solar Radiation Research Laboratory (SRRL). The OATS sunlight availability losses included downtime when

  11. Accelerated weathering-induced degradation of poly(lactic acid) fiber studied by near-infrared (NIR) hyperspectral imaging.

    PubMed

    Shinzawa, Hideyuki; Nishida, Masakazu; Tanaka, Toshiyuki; Kanematsu, Wataru

    2012-04-01

    Hydrolysis degradation of a set of drawn poly(lactic acid) (PLA) fibers was induced by an accelerated weathering test, radiating ultraviolet (UV) light under a certain temperature and humidity. The fine features of the transient behavior of the PLA fibers were captured by near-infrared (NIR) hyperspectral imaging. The PLA fibers showed a gradual decrease in mechanical property (e.g., tensile strength), indicating hydrolysis degradation. Thus, the detailed analysis of the spectral variation, in turn, offers useful information on the molecular-level degradation behavior of the drawn PLA fibers. The variation of the spectral intensity as well as band position shift of the crystalline band of PLA was analyzed. The spectral intensity of the crystalline band of PLA showed gradual decrease, suggesting the decrease in molecular weight induced by the hydrolysis degradation. In addition, the crystalline band also exhibited a coinciding shift to the lower wavenumber direction with the weathering test, revealing cleavage-induced crystallization of the PLA samples. Consequently, the hydrolysis degradation induced by the weathering test substantially accelerates predominant degradation of the amorphous structure of the PLA and such variation of the molecular structure, in turn, brings less ductility to the PLA fiber.

  12. Chemical vs. Physical Acceleration of Cement Hydration

    PubMed Central

    Bentz, Dale P.; Zunino, Franco; Lootens, Didier

    2016-01-01

    Cold weather concreting often requires the use of chemical accelerators to speed up the hydration reactions of the cement, so that setting and early-age strength development will occur in a timely manner. While calcium chloride (dihydrate – CaCl2·2H2O) is the most commonly used chemical accelerator, recent research using fine limestone powders has indicated their high proficiency for physically accelerating early-age hydration and reducing setting times. This paper presents a comparative study of the efficiency of these two approaches in accelerating hydration (as assessed via isothermal calorimetry), reducing setting times (Vicat needle), and increasing early-age mortar cube strength (1 d and 7 d). Both the CaCl2 and the fine limestone powder are used to replace a portion of the finest sand in the mortar mixtures, while keeping both the water-to-cement ratio and volume fractions of water and cement constant. Studies are conducted at 73.4 °F (23°C) and 50 °F (10 °C), so that activation energies can be estimated for the hydration and setting processes. Because the mechanisms of acceleration of the CaCl2 and limestone powder are different, a hybrid mixture with 1 % CaCl2 and 20 % limestone powder (by mass of cement) is also investigated. Both technologies are found to be viable options for reducing setting times and increasing early-age strengths, and it is hoped that concrete producers and contractors will consider the addition of fine limestone powder to their toolbox of techniques for assuring performance in cold weather and other concreting conditions where acceleration may be needed. PMID:28077884

  13. The erosion of the beaches on the coast of Alicante: Study of the mechanisms of weathering by accelerated laboratory tests.

    PubMed

    López, I; López, M; Aragonés, L; García-Barba, J; López, M P; Sánchez, I

    2016-10-01

    One of the main problems that coasts around the world present, is the regression and erosion of beaches. However, the factors involved in these processes are unclear. In this study, the influence of sediment erosion on beach regression has been analysed. In order to do that, a three-step investigation has been carried out. Firstly, coastline variations of four Spanish beaches have been analysed. Secondly, a study on sediment position along the beach profile has been developed. Finally, the process that beach sediments undergo along the surf zone when they are hit by the incident waves has been simulated by an accelerated particle weathering test. Samples of sand and shells were subjected to this accelerated particle weathering test. Results were supplemented with those from carbonate content test, XRD, SEM and granulometric analysis. Results shows a cross-shore classification of sediments along the beach profile in which finer particles move beyond offshore limit. Besides, it was observed that sediment erosion process is divided into three sages: i) particles wear due to crashes ii) dissolution of the carbonate fraction, and iii) breakage and separation of mineral and carbonate parts of particles. All these processes lead to a reduction of particle size. The mechanism responsible of beach erosion would consist of multiples and continuous particle location exchanges along the beach profile as a consequence of grain-size decrease due to erosion.

  14. Brazilian coal mining residues and sulphide oxidation by Fenton's reaction: an accelerated weathering procedure to evaluate possible environmental impact.

    PubMed

    Silva, L F O; Querol, X; da Boit, K M; Fdez-Ortiz de Vallejuelo, S; Madariaga, J M

    2011-02-15

    Fenton's reaction is proposed as an accelerated weathering test for sulphides associated with Brazilian Coal Mining Residues (CMR), that are exposed to oxygen and water during the mining of coal. TEM and SEM/EDX were used to evaluate the nature, occurrence and distribution of minerals in remaining coals and other lithological units, before and after applying the test. Oxidation of CMRs was examined by analyzing soluble sulphur (sulphate) and dissolved metals by ICP-MS or ICP OES. As dissolved sulphate increases, dissolved Zn, Cd, Cu and Co concentrations increase, leading to undetectable amounts in the remaining solid phases; dissolved Ni and Mn also increase with the mobilized sulphur, but the remainder in the solids is the most important fraction; Fe and Pb are not mobilized due to precipitation as jarosite or hematite in the case of Fe or as sulphate in the case of Pb. Agreement between the observed results and the predictions by geochemical modelling is discussed.

  15. Effect of TiO2-Crystal Forms on the Photo-Degradation of EVA/PLA Blend Under Accelerated Weather Testing

    NASA Astrophysics Data System (ADS)

    Van Cong, Do; Trang, Nguyen Thi Thu; Giang, Nguyen Vu; Lam, Tran Dai; Hoang, Thai

    2016-05-01

    Photo-degradation of poly (ethylene-co-vinyl acetate) (EVA)/poly (lactic acid) (PLA) blend and EVA/PLA/TiO2 nanocomposites was carried out under accelerated weather testing conditions by alternating cycles of ultraviolet (UV) light and moisture at controlled and elevated temperatures. The characters, properties, and morphology of these materials before and after accelerated weather testing were determined by Fourier transform infrared spectroscopy, colour changes, viscosity, tensile test, thermogravimetric analysis, and field emission scanning electron microscopy. The increases in the content of oxygen-containing groups, colour changes; the decreases in viscosity, tensile properties, and thermal stability of these materials after accelerated weather testing are the evidence for the photo-degradation of the blend and nanocomposites. After accelerated weather testing, the appearance of many micro-holes and micro-pores on the surface of the collected samples was observed. The photo-degradation degree of the nanocomposites depended on the TiO2-crystal form. Rutile TiO2 do not enhance the degradation, but anatase and mixed crystals TiO2 nanoparticles promoted the degradation of the nanocomposites. Particularly, the mixed crystals TiO2 nanoparticles showed the highest photo-catalytic activity of the nanocomposites.

  16. Warm and dry weather accelerates and elongates Cladosporium spore seasons in Poland.

    PubMed

    Kasprzyk, Idalia; Kaszewski, Boguslaw Michal; Weryszko-Chmielewska, Elzbieta; Nowak, Malgorzata; Sulborska, Aneta; Kaczmarek, Joanna; Szymanska, Agata; Haratym, Weronika; Jedryczka, Malgorzata

    Temperature is the environmental factor that systematically changes for decades and, as in plants and animals, can significantly affect the growth and development of fungi, including the abundance of their sporulation. During the time of study (2010-2012), a rapid increase in air temperature was observed in Poland, which coincided with the substantial decrease in rainfall. The increase in annual mean temperatures at three monitoring sites of this study was 0.9 °C in Lublin and Rzeszow (east Poland) and 2.0 °C in Poznan (west Poland). Such warming of air masses was comparable to the average global air temperature rise in the period of 1880-2012 accounting for 0.85 °C, as reported by the Intergovernmental Panel on Climate Change. Moreover, there was a substantial decrease in rainfall, ranging from 32.7 % (Poznan) to 43.0 % (Rzeszow). We have demonstrated that under such conditions the mean and median values of total Cladosporium spore counts significantly increased and the spore seasons were greatly accelerated. Moreover, earlier start and later end of the season caused its extension, lasting from over 20 days in Rzeszow to around 60 days in Lublin and Poznan, when the cumulative amount of 5-95 % of spores was considered. The time of reaching the cumulative amount of 50 % of spores was up to 25 days earlier (difference in Poznan between 2010 and 2012). There was also a striking acceleration of the date of the maximal Cladosporium spore concentration per cubic metre of air (26 days for Lublin, 43 for Poznan and 56 for Rzeszow).

  17. Electrochemical Acceleration of Carbonate and Silicate Weathering for CO2 Mitigation

    NASA Astrophysics Data System (ADS)

    Rau, G. H.; Carroll, S.

    2011-12-01

    Carbonate and many silicate minerals dissolve in strong acids, and such acids are commonly generated at the anode of a conventional saline water electrolysis cell. It was therefore reasoned that encasing such an anode with base minerals would lead to enhanced mineral dissolution and hence increased hydroxide (base) generation at the cathode, formed in course of splitting water, generating H2 and OH-. Subsequent exposue of the alkalized solution to CO2 (e.g., as in air) would lead to absorption of the CO2 and formation of stable dissolved or solid (bi)carbonates for carbon sequestration. Previously, it has been demonstrated that mineral carbonate encasement of a seawater electrolysis cell anode indeed generated basic solutions in excess of pH 9 that were subsequently neutralized via contact with air CO2, increasing the carbon content of the initial seawater by 30% (Rau, G.H. 2008. Environ Sci. Techol. 42, 8935-). To test such a weathering/CO2 capture scheme using silicate minerals, either powdered wollastonite or ultramafic rock standard (UM-4) was encased around the anode of an electrolysis cell composed of graphite electrodes and a 0.25M Na2SO4 electrolyte solution. After 0.5 to 1.5 hrs of electricity application (3.5Vdc, 5-10mA), the electrolyte pH rose to as much as 11.1 (initial and blank solution pH's <6.6). Subequent bubbling of these basic solutions with air lowered pH by at least 2 units and increased dissolve carbon content (primarily bicarbonate) by as much as 50X that of the blanks. While Ca2+ and Mg2+ concentrations were elevated, these were insufficient to balance the majority of the bicarbonate anions formed in solution. This suggests that in these experiments the silicate minerals acted as a neutralizer of the anolyte acid, H2SO4, forming mostly insoluble CaSO4 and MgSO4 at the anode. This then allowed NaOH normally produced at the cathode to accumulate in solution, in turn reacting with air CO2 to form NaHCO3. Longer electrolysis times and

  18. Extrapolating Accelerated UV Weathering Data: Perspective From PVQAT Task Group 5 (Presentation)

    SciTech Connect

    Miller, D.; Annigoni, E.; Ballion, A.; Bokria, J.; Bruckman, L.; Burns, D.; Elliott, L.; French, R.; Fowler, S.; Gu, X.; Honeker, C.; Khonkar, H.; Kohl, M.; Krommenhoek, P.; Peret-Aebi, L.; Phillips, N.; Scott, K.; Sculati-Meillaud, F.; Shioda, T.

    2015-02-01

    Taskgroup 5 (TG5) is concerned with a accelerated aging standard incorporating factors including ultraviolet radiation, temperature, and moisture. Separate experiments are being conducted in support of a test standard via the regional sub-groups in Asia, Europe, and the United States. The authors will describe the objectives and timeline for the TG5 interlaboratory study being directed out of the USA. Qualitative preliminary data from the experiment is presented. To date, the encapsulation transmittance experiment has: replicated behaviors of fielded materials (including specimen location- and formulation additive-specific discoloration); demonstrated coupling between UV aging and temperature; demonstrated that degradation in EVA results from UV- aging; and obtained good qualitative comparison between Xe and UVA-340 sources for EVA. To date, the encapsulation adhesion experiment (using the compressive shear test to quantify strength of attachment) has demonstrated that attachment strength can decrease drastically (>50%) with age; however, early results suggest significant factor (UV, T, RH) dependence. Much remains to be learned about adhesion.

  19. Cracking and delamination behaviors of photovoltaic backsheet after accelerated laboratory weathering

    NASA Astrophysics Data System (ADS)

    Lin, Chiao-Chi; Lyu, Yadong; Hunston, Donald L.; Kim, Jae Hyun; Wan, Kai-Tak; Stanley, Deborah L.; Gu, Xiaohong

    2015-09-01

    The channel crack and delamination phenomena that occurred during tensile tests were utilized to study surface cracking and delamination properties of a multilayered backsheet. A model sample of commercial PPE (polyethylene terephthalate (PET)/PET/ethylene vinyl acetate (EVA)) backsheet was studied. Fragmentation testing was performed after accelerated aging with and without ultraviolet (UV) irradiation in two relative humidity (RH) levels (5 % RH and 60 % RH) at elevated temperature (85 °C) conditions for 11 days and 22 days. Results suggest that the embrittled surface layer resulting from the UV photo-degradation is responsible for surface cracking when the strain applied on the sample is far below the yielding strain (2.2 %) of the PPE sample. There was no surface cracking observed on the un-aged sample and samples aged without UV irradiation. According to the fragmentation testing results, the calculated fracture toughness (KIC) values of the embrittled surface layer are as low as 0.027 MPa·m1/2 to 0.104 MPa·m1/2, depending on the humidity levels and aging times. Surface analysis using attenuated total reflectance Fourier transform infrared and atomic force microscopy shows the degradation mechanism of the embrittled surface layer is a combination of the photodegradation within a certain degradation depth and the moisture erosion effect depending on the moisture levels. Specifically, UV irradiation provides a chemical degradation effect while moisture plays a synergistic effect on surface erosion, which influences surface roughness after aging. Finally, there was no delamination observed during tensile testing in this study, suggesting the surface cracking problem is more significant than the delamination for the PPE backsheet material and conditions tested here.

  20. Evolution of the microstructure of unmodified and polymer modified asphalt binders with aging in an accelerated weathering tester.

    PubMed

    Menapace, Ilaria; Masad, Eyad

    2016-09-01

    This paper presents findings on the evolution of the surface microstructure of two asphalt binders, one unmodified and one polymer modified, directly exposed to aging agents with increasing durations. The aging is performed using an accelerated weathering tester, where ultraviolet radiation, oxygen and an increased temperature are applied to the asphalt binder surface. Ultraviolet and dark cycles, which simulated the succession of day and night, alternated during the aging process, and also the temperature varied, which corresponded to typical summer day and night temperatures registered in the state of Qatar. Direct aging of an exposed binder surface is more effective in showing microstructural modifications than previously applied protocols, which involved the heat treatment of binders previously aged with standardized methods. With the new protocol, any molecular rearrangements in the binder surface after aging induced by the heat treatment is prevented. Optical photos show the rippling and degradation of the binder surface due to aging. Microstructure images obtained by means of atomic force microscopy show gradual alteration of the surface due to aging. The original relatively flat microstructure was substituted with a profoundly different microstructure, which significantly protrudes from the surface, and is characterized by various shapes, such as rods, round structures and finally 'flower' or 'leaf' structures.

  1. Accelerated Weathering of Rocks.

    DTIC Science & Technology

    1977-08-01

    Dry tests en polished specimens with alternating heating and co- oling actions; ii) Wet tests in destilled water, with alternating...Rock-type Dry tests KxlO2 Wet tests KxlO2 Sound rock SR 3.64 8.31 Medium altered rock MAR 4.96 31.58 Very altered rock VAR 8.89 116.20 TABLE X...Sound rock SR Medium altered rock Very altered rock" KAR VAR ’ Reflectivity R (%) dry test wet test dry test wet test dry test wet

  2. Tree-mycorrhiza symbiosis accelerate mineral weathering: Evidences from nanometer-scale elemental fluxes at the hypha-mineral interface

    NASA Astrophysics Data System (ADS)

    Bonneville, Steeve; Morgan, Daniel J.; Schmalenberger, Achim; Bray, Andrew; Brown, Andrew; Banwart, Steven A.; Benning, Liane G.

    2011-11-01

    In soils, mycorrhiza (microscopic fungal hypha) living in symbiosis with plant roots are the biological interface by which plants obtain, from rocks and organic matter, the nutrients necessary for their growth and maintenance. Despite their central role in soils, the mechanism and kinetics of mineral alteration by mycorrhiza are poorly constrained quantitatively. Here, we report in situ quantification of weathering rates from a mineral substrate, (0 0 1) basal plane of biotite, by a surface-bound hypha of Paxillus involutus, grown in association with the root system of a Scots pine, Pinus sylvestris. Four thin-sections were extracted by focused ion beam (FIB) milling along a single hypha grown over the biotite surface. Depth-profile of Si, O, K, Mg, Fe and Al concentrations were performed at the hypha-biotite interface by scanning transmission electron microscopy-energy dispersive X-ray spectroscopy (STEM-EDX). Large removals of K (50-65%), Mg (55-75%), Fe (80-85%) and Al (75-85%) were observed in the topmost 40 nm of biotite underneath the hypha while Si and O are preserved throughout the depth-profile. A quantitative model of alteration at the hypha-scale was developed based on solid-state diffusion fluxes of elements into the hypha and the break-down/mineralogical re-arrangement of biotite. A strong acidification was also observed with hypha bound to the biotite surface reaching pH < 4.6. When consistently compared with the abiotic biotite dissolution, we conclude that the surface-bound mycorrhiza accelerate the biotite alteration kinetics between pH 3.5 and 5.8 to ˜0.04 μmol biotite m -2 h -1. Our current work reaffirms that fungal mineral alteration is a process that combines our previously documented bio-mechanical forcing with the μm-scale acidification mediated by surface-bound hypha and a subsequent chemical element removal due to the fungal action. As such, our study presents a first kinetic framework for mycorrhizal alteration at the hypha-scale under

  3. Novel Hydroxyapatite Coatings for the Conservation of Marble and Limestone

    NASA Astrophysics Data System (ADS)

    Naidu, Sonia

    Marble and limestone are calcite-based materials used in the construction of various structures, many of which have significant artistic and architectural value. Unfortunately, due to calcite's high dissolution rate, these stones are susceptible to chemically-induced weathering in nature. Limestone, due to its inherent porosity, also faces other environmental weathering processes that cause weakening from disintegration at grain boundaries. The treatments presently available are all deficient in one way or another. The aim of this work is to examine the feasibility of using hydroxyapatite (HAP) as a novel protective coating for marble and limestone, with two goals: i) to reduce acid corrosion of marble and ii) to consolidate physically weathered limestone. The motivation for using HAP is its low dissolution rate and structural compatibility with calcite. Mild, wet chemical synthesis routes, in which inorganic phosphate-based solutions were reacted with marble and limestone, alone and with other precursors, were used to produce HAP films. Film nucleation, growth and phase evolution were studied on marble to understand film formation and determine the optimal synthesis route. An acid resistance test was developed to investigate the attack mechanism on marble and quantify the efficacy of HAP-based coatings. Film nucleation and growth were dependent on substrate surface roughness and increased with calcium and carbonate salt additions during synthesis. Acid attack on marble occurred via simultaneous dissolution at grain boundaries, twin boundaries and grain surfaces. HAP provided intermediate protection against acid attack, when compared to two conventional treatments. Its ability to protect the stone from acid was not as significant as predicted from dissolution kinetics and this was attributed to incomplete coverage and residual porosity within the film, arising from its flake-like crystal growth habit, which enabled acid to access the underlying substrate. The

  4. Elemental analysis of limestone samples from Ewekoro limestone deposit in southwest Nigeria

    NASA Astrophysics Data System (ADS)

    Obiajunwa, E. I.; Nwachukwu, J. I.

    2000-10-01

    Limestone samples of different colours from Ewekoro limestone deposit in Ogun State, Nigeria were subjected to elemental analysis by proton-induced X-ray emission (PIXE) and proton-induced gamma-ray emission (PIGME) techniques. The irradiation was by 2.5 MeV proton beams from the ion beam analysis (IBA) facility of the 3 MV Van de Graaff accelerator at the Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights. Elemental composition and concentrations of 22 major, minor and trace elements were determined. The NIST geological standard, NBS278, was analysed for quality assurance. The concentrations of the major elements (Ca, Fe, K and Al) are similar in the samples while the other major elements differed. Calcium accounts for about 38%, giving 86.8% CaCO 3 content in the limestones. The major elements (Al, Ca, Fe, Si, S and K), present in the limestones, were also found to be enriched in airborne particulate matter studied by earlier workers, thus confirming cement dust as the major contributor to the particulate matter within and around cement factories.

  5. Accelerated Weathering of Waste Glass at 90°C with the Pressurized Unsaturated Flow (PUF) Apparatus: Implications for Predicting Glass Corrosion with a Reactive Transport Model

    SciTech Connect

    Pierce, Eric M.; Bacon, Diana H.

    2009-09-21

    The interest in the long-term durability of waste glass stems from the need to predict radionuclide release rates from the corroding glass over geologic time-scales. Several long-term test methods have been developed to accelerate the glass-water reaction [drip test, vapor hydration test, product consistency test-B, and pressurized unsaturated flow (PUF)]. Currently, the PUF test is the only method that can mimic the unsaturated hydraulic properties expected in a subsurface disposal facility and simultaneously monitor the glass-water reaction. PUF tests are being conducted to accelerate the weathering of glass and validate the model parameters being used to predict long-term glass behavior. One dimensional reactive chemical transport simulations of glass dissolution and secondary phase formation during a 1.5-year long PUF experiment was conducted with the subsurface transport over reactive multi-phases (STORM) code. Results show that parameterization of the computer model by combining direct laboratory measurements and thermodynamic data provides an integrated approach to predicting glass behavior over geologic-time scales.

  6. Mineralogical characterization of the Shelburne Marble and the Salem limestone: Test stones used to study the effects of acid rain

    SciTech Connect

    McGee, E.S.

    1989-01-01

    The Salem Limestone and the Shelburne Marble are representative of limestones and marbles commonly used in buildings and monuments. Both stones are composed predominantly of calcite. The Salem Limestone is homogeneous in composition and mineralogic characteristics throughout the test block. The Shelburne Marble has compositionally homogeneous mineral phases, but the distribution of those phases within the test block is random. The mineralogy and physical characteristics of the Shelburne Marble and Salem Limestone test blocks described in the study provide a baseline for future studies of the weathering behavior of these stones. Because the Shelburne Marble and the Salem Limestone are representative of typical commercial marbles and limestones, they are likely to be useful in a consortium study of the effects of acid precipitation on these two types of building stones.

  7. Structural studies in limestone sulfidation

    SciTech Connect

    Fenouil, Laurent A.

    1993-05-01

    This study investigates the sulfidation of limestone at high temperatures (700--900°C) as the first step in the design of a High-Temperature Coal-Gas Clean-Up system using millimeter-size limestone particles. Several workers have found that the rate of this reaction significantly decreases after an initial 10 to 15% conversion of CaCO3 to CaS. The present work attempts to explain this feature. It is first established that millimeter-size limestone particles do not sinter at temperatures up to the CaCO3 calcination point (899°C at 1.03 bar CO2} partial pressure). It is then shown that CaS sinters rapidly at 750 to 900°C if CO2 is present in the gas phase. Scanning Electron Microscope (SEM) photographs and Electron Dispersive Spectroscopy (EDS) data reveal that the CaS product layer sinters and forms a quasi-impermeable coating around the CaCO3 grains that greatly hinders more H2S from reaching the still unreacted parts of the stone. Moreover, most of the pores initially present within the limestone structure begin to disappear or, at least, are significantly reduced in size. From then on, subsequent conversion is limited by diffusion of H2S through the CaS layer, possibly by S2- ionic diffusion. The kinetics is then adequately described by a shrinking-core model, in which a sharp front of completely converted limestone is assumed to progress toward the center of the pellet. Finally, experimental evidence and computer simulations using simple sintering models suggest that the CaS sintering, responsible for the sharp decrease in the sulfidation rate, is surface-diffusion controlled.

  8. 21 CFR 184.1409 - Ground limestone.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Ground limestone. 184.1409 Section 184.1409 Food... Specific Substances Affirmed as GRAS § 184.1409 Ground limestone. (a) Ground limestone consists essentially (not less than 94 percent) of calcium carbonate (CaCO3) and is prepared by the crushing, grinding,...

  9. 21 CFR 184.1409 - Ground limestone.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Ground limestone. 184.1409 Section 184.1409 Food... Specific Substances Affirmed as GRAS § 184.1409 Ground limestone. (a) Ground limestone consists essentially (not less than 94 percent) of calcium carbonate (CaCO3) and is prepared by the crushing, grinding,...

  10. 21 CFR 184.1409 - Ground limestone.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ground limestone. 184.1409 Section 184.1409 Food... Specific Substances Affirmed as GRAS § 184.1409 Ground limestone. (a) Ground limestone consists essentially (not less than 94 percent) of calcium carbonate (CaCO3) and is prepared by the crushing, grinding,...

  11. 21 CFR 184.1409 - Ground limestone.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Ground limestone. 184.1409 Section 184.1409 Food... GRAS § 184.1409 Ground limestone. (a) Ground limestone consists essentially (not less than 94 percent) of calcium carbonate (CaCO3) and is prepared by the crushing, grinding, and classifying of...

  12. 21 CFR 184.1409 - Ground limestone.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ground limestone. 184.1409 Section 184.1409 Food... Specific Substances Affirmed as GRAS § 184.1409 Ground limestone. (a) Ground limestone consists essentially (not less than 94 percent) of calcium carbonate (CaCO3) and is prepared by the crushing, grinding,...

  13. CALCIUM CARBONATE DISSOLUTION RATE IN LIMESTONE CONTACTORS

    EPA Science Inventory

    The rate of carbonate mineral dissolution from limestone was studied using a rotating disk apparatus and samples of limestone of varied composition. The purpose of this study was to determine the effect of limestone composition on the kinetics of carbonate mineral dissolution. Th...

  14. EFFECT OF AN ACID RAIN ENVIRONMENT ON LIMESTONE SURFACES.

    USGS Publications Warehouse

    Mossotti, Victor G.; Lindsay, James R.; Hochella, Michael F.

    1987-01-01

    Salem limestone samples were exposed to weathering for 1 y in several urban and one rural environments. Samples exposed in the rural location were chemically indistinguishable from the freshly quarried limestone, whereas all samples collected from urban exposure sites developed gypsum stains on the ground-facing surfaces where the stones were not washed by precipitation. The gas-solid reaction of SO//2 with calcite was selected for detailed consideration. It appears from the model that under arid conditions, the quantity of stain deposited on an unwashed surface is independent of atmospheric SO//2 concentration once the surface has been saturated with gypsum. Under wet conditions, surface sulfation and weight loss are probably dominated by mechanisms involving wet stone. However, if the rain events are frequent and delimited by periods of dryness, the quantity of gypsum produced by a gas-solid reaction mechanism should correlate with both the frequency of rain events and the atmospheric SO//2 level.

  15. Weather Watch

    ERIC Educational Resources Information Center

    Bratt, Herschell Marvin

    1973-01-01

    Suggests a number of ways in which Federal Aviation Agency weather report printouts can be used in teaching the weather section of meteorology. These weather sequence reports can be obtained free of charge at most major airports. (JR)

  16. Heated Rack For Weathering Tests

    NASA Technical Reports Server (NTRS)

    Cuddihy, Edward F.; Willis, Paul B.

    1989-01-01

    Outdoor photothermal aging reactor (OPTAR) simple device exposing polymer specimens to both heat and natural sunlight. Intended to provide accelerated aging data for service life of polymers used in outdoor environments. In principle, OPTAR accelerates (but does not initiate) degradation of polymers resulting from sunlight and other weathering effect (eg. rain, wind, ozone). Aging of tested material accelerated, but under almost-natural conditions.

  17. Severe Weather

    ERIC Educational Resources Information Center

    Forde, Evan B.

    2004-01-01

    Educating the public about safety issues related to severe weather is part of the National Oceanic and Atmospheric Administration's (NOAA) mission. This month's insert, Severe Weather, has been created by NOAA to help educate the public about hazardous weather conditions. The four types of severe weather highlighted in this poster are hurricanes,…

  18. Severe Weather

    ERIC Educational Resources Information Center

    Forde, Evan B.

    2004-01-01

    Educating the public about safety issues related to severe weather is part of the National Oceanic and Atmospheric Administration's (NOAA) mission. This article deals with a poster entitled, "Severe Weather," that has been created by NOAA to help educate the public about hazardous weather conditions. The four types of severe weather highlighted in…

  19. Sodium-limestone double alkali flue gas desulfurization process with improved limestone utilization

    SciTech Connect

    Biolchini, R.J.; Boward, W.L. Jr.; Wang, K.H.

    1987-08-18

    This patent describes a sodium-limestone double alkali process for the continuous desulfurization of flue gas, having the steps of absorbing sulfur dioxide from an SO/sub 2/-containing gas stream in an absorber with an aqueous solution of sodium sulfite and sodium bisulfite, diverting at least a portion of the absorber effluent solution for regeneration with limestone, introducing limestone into the diverted absorber effluent solution to convert bisulfite to sulfite, separating by-product solids from the limestone-treated solution, and returning regenerated solution to the absorber, the improvement for increasing the utilization of the limestone used during the regeneration operation.

  20. Water transport in limestone by X-ray CAT scanning

    USGS Publications Warehouse

    Mossoti, Victor G.; Castanier, Louis M.

    1989-01-01

    The transport of water through the interior of Salem limestone test briquettes can be dynamically monitored by computer aided tomography (commonly called CAT scanning in medical diagnostics). Most significantly, unless evaporation from a particular face of the briquette is accelerated by forced air flow (wind simulation), the distribution of water in the interior of the briquette remains more or less uniform throughout the complete drying cycle. Moreover, simulated solar illumination of the test briquette does not result in the production of significant water gradients in the briquette under steady-state drying conditions.

  1. Weather & Weather Maps. Teacher's Manual.

    ERIC Educational Resources Information Center

    Metro, Peter M.; Green, Rachel E.

    This guide is intended to provide an opportunity for students to work with weather symbols used for reporting weather. Also included are exercises in location of United States cities by latitude and longitude, measurement of distances in miles and kilometers, and prediction of weather associated with various types of weather fronts. (RE)

  2. Epilithic and endolithic bacterial communities in limestone from a Maya archaeological site.

    PubMed

    McNamara, Christopher J; Perry, Thomas D; Bearce, Kristen A; Hernandez-Duque, Guillermo; Mitchell, Ralph

    2006-01-01

    Biodeterioration of archaeological sites and historic buildings is a major concern for conservators, archaeologists, and scientists involved in preservation of the world's cultural heritage. The Maya archaeological sites in southern Mexico, some of the most important cultural artifacts in the Western Hemisphere, are constructed of limestone. High temperature and humidity have resulted in substantial microbial growth on stone surfaces at many of the sites. Despite the porous nature of limestone and the common occurrence of endolithic microorganisms in many habitats, little is known about the microbial flora living inside the stone. We found a large endolithic bacterial community in limestone from the interior of the Maya archaeological site Ek' Balam. Analysis of 16S rDNA clones demonstrated disparate communities (endolithic: >80% Actinobacteria, Acidobacteria, and Low GC Firmicutes; epilithic: >50% Proteobacteria). The presence of differing epilithic and endolithic bacterial communities may be a significant factor for conservation of stone cultural heritage materials and quantitative prediction of carbonate weathering.

  3. Drenov Grič black limestone as a heritage stone from Slovenia

    NASA Astrophysics Data System (ADS)

    Kramar, Sabina; Rožič, Boštjan; Žbona, Nina; Bedjanič, Mojca; Mladenović, Ana

    2016-04-01

    exposed to climatic influences, chromatic weathering and salt weathering are recognized as the main deterioration phenomena of this limestone on monuments.

  4. Magnetic hysteresis of limestones: facies control?

    NASA Astrophysics Data System (ADS)

    Borradaile, Graham J.; Chow, Nancy; Werner, Tomasz

    1993-03-01

    The hysteresis properties of 116 non-red, marine limestones from 92 localities indicate that remanence is carried by magnetite of pseudo-single-domain (PSD) and small multidomain (MD) size. Pelagic limestones have paramagnetic matrices and hysteresis properties compatible with larger PSD or MD grain sizes of magnetite, probably associated with detrital clay minerals introduced by pelagic rain-out. Thus they may be less suitable recorders of stable remanence. Other limestone facies (excepting dolomitized examples) have diamagnetic matrices. They include shallow—subtidal limestones which tend to have smaller PSD sizes of magnetite, as do backreef—lagoonal, undifferentiated-shelf and reef facies. It is believed that the wide geographical and temporal range of samples minimizes effects related to post-compaction groundwater flow (late diagenesis) and that the associations recognized should be tested in future studies.

  5. Comparative study of porous limestones used in heritage structures in Cyprus and in Hungary

    NASA Astrophysics Data System (ADS)

    Theodoridou, Magdalini; Ioannou, Ioannis; Rozgonyi-Boissinot, Nikoletta; Török, Ákos

    2015-04-01

    Porous limestone is widely used as construction material in the monuments of Cyprus and Hungary. The present study compares the physical properties of a bioclastic limestone from Cyprus and an oolitic limestone from Hungary. Petra Gerolakkou is a Pliocene limestone from Cyprus that originates from the district of Nicosia, the island's capital. It has been extensively used throughout the years in construction and restoration projects, particularly in the Nicosia area. Distinctive examples of its use can be found in the majority of the most important historic monuments in Nicosia, such as the Venetian walls and fortifications, churches (e.g. the Agia Sofia Cathedral), the archbishop and presidential palaces and a high number of other traditional buildings. The studied Miocene limestone from Hungary was exploited from Sóskút quarry (15-20 km W-SW to Budapest). The quarry provided stone for emblematic monuments of the capital of Hungary such as the Parliament building, Mathias Church, the Opera House and Citadella. In this study, mechanical parameters for both aforementioned stones, such as uniaxial compressive and tensile strengths, were tested under laboratory conditions. Their density, porosity and water absorption were also compared. The studied limestone from Cyprus exhibits porosity values within the range of 48-51%, apparent density between 1340 and 1400 kg/m3 and strength values under uniaxial compressive load between 1.2 and 2.8 MPa. This lithotype is also considered susceptible to salt decay, since an approximate mass loss of 12.5% is noted after 15 salt crystallization artificial weathering cycles. The porosity of the Hungarian limestone is in the order of 16-35%, the bulk density is 1600-1950 kg/m3, while the compressive strength is 2.5-15 MPa. Durability tests indicate that even after 10 freeze-thaw cycles the loss in strength is dramatic. Test results indicate that use of porous limestone in both countries is common and fabric strongly controls the

  6. The behavior limestone under explosive load

    NASA Astrophysics Data System (ADS)

    Orlov, M. Yu; Orlova, Yu N.; Bogomolov, G. N.

    2016-11-01

    Limestone behavior under explosive loading was investigated. The behavior of the limestone by the action of the three types of explosives, including granular, ammonite and emulsion explosives was studied in detail. The shape and diameter of the explosion craters were obtained. The observed fragments after the blast have been classified as large, medium and small fragments. Three full-scale experiments were carried out. The research results can be used as a qualitative test for the approbation of numerical methods.

  7. [Limestone and pyrite-limestone constructed wetlands for treating river water].

    PubMed

    Zhang, Jing; Li, Rui-hua; Li, Jie; Hu, Jun-song; Sun, Qian-qian

    2013-09-01

    Polluted river water was treated with limestone and pyrite-limestone subsurface horizontal constructed wetlands. The aims were to know the performance of two wetlands on removal of common pollutants, especially nitrogen and phosphorus, and analyze the actions of these minerals. The relationship between hydraulic retention time and purification performance of two constructed wetlands was studied. The optimal hydraulic retention time for pollutant removal was about 3 d, The average removal efficiency of COD, TN and TP were 51%, 70% and 95%, respectively. With same influent and hydraulic loading, the average removal efficiency of COD, NH4+ -N, TN and TP were 53.93%, 82.13%, 66%, 50.9%, and 51.66%, 77.43%, 72.06%, 97.35% for limestone and pyrite-limestone constructed wetlands, respectively. There were few differences between limestone and pyrite-limestone wetlands on COD removal, but the nitrogen and phosphorus removal of pyrite-limestone constructed wetland was higher than that of limestone constructed wetland. The phosphorus removal of pyrite-limestone wetland was more efficiency and stable, not affected by temperature.

  8. Condition assessment of a highly porous limestone fortress: damage categories and structural integrity

    NASA Astrophysics Data System (ADS)

    Török, Ákos; Czinder, Balázs; Farkas, Orsolya; Görög, Péter; Kopecskó, Katalin; Lógó, János; Rozgonyi-Boissinot, Nikoletta; Vásárhelyi, Balázs

    2016-04-01

    An emblematic monument the Citadella fortress of Budapest has been studied in details to assess the condition of stone structure. The fortress is a large stone structure of 220 m in length and 60 m in width. The height of the porous limestone walls are in between 12-16 metres. The fortress was completed in 1854 but has been partly rebuilt due to changes in function and war related structural damages. The present paper provides an overview of the lithology, weathering forms and structural condition of the fortress related to a forthcoming restoration-reconstruction project. To assess the condition of stone both on site and laboratory analyses were performed. Lithological varieties were documented. Major identified lithotypes are porous oolitic limestone, less porous bioclastic limestone and fine grained highly porous limestone. To identify wet zones portable moisture meter was applied. Surface strength and weathering grade were also assessed using Schmidt hammer and Duroscop. Decay features were diagnosed and mapped. The most common forms are white weathering crusts, scaling and blistering of crusts as well as granular disintegration. Black weathering crusts were also recognized. Laboratory tests were focused on mechanical properties of stones and on mineralogical and chemical compositional analyses. Small samples of stone were collected and tested by optical microscopy, SEM-EDX, XRD and Thermogravimetric analyses. Laboratory analyses proved that the major salt responsible for the damage of external walls is gypsum, although significant amount of halite and hygroscopic salts were found both on the external walls and in the interior parts of the fortress. During structural analyses displacement of walls, tilting and major amount of cracks were recognized. Loss of material and subsidence also caused problems and at some places unstable wall sections were recognized.

  9. Laser Removal of Protective Treatments on Limestone

    NASA Astrophysics Data System (ADS)

    Gómez-Heras, M.; Rebollar, E.; Alvarez de Buergo, M.; Oujja, M.; Fort, R.; Castillejo, M.

    This work presents an investigation of the laser removal of polymeric materials acting as consolidants and water-repellents on limestone used on buildings of architectural and artistic value. The removal of the consolidant Paraloid B-72 and the water-repellent product Tegosivin HL-100, applied on samples of Colmenarand Bateig limestone, was studied as a function of the laser wavelength, by using the four harmonics of a Q-switched Nd:YAG laser (1064, 532, 355 and 266 nm). Elimination of the coatings and subsequent surface modifications were monitored through colorimetry, roughness measurements and scanning electron microscopy (SEM). The fundamental laser radiation was effective in removing the treatments, although thermal alteration processes were induced on the calcite crystals of the limestone. The best results were obtained by irradiation in the near UV at 355 nm.

  10. Weather Instruments.

    ERIC Educational Resources Information Center

    Brantley, L. Reed, Sr.; Demanche, Edna L.; Klemm, E. Barbara; Kyselka, Will; Phillips, Edwin A.; Pottenger, Francis M.; Yamamoto, Karen N.; Young, Donald B.

    This booklet presents some activities to measure various weather phenomena. Directions for constructing a weather station are included. Instruments including rain gauges, thermometers, wind vanes, wind speed devices, humidity devices, barometers, atmospheric observations, a dustfall jar, sticky-tape can, detection of gases in the air, and pH of…

  11. Wacky Weather

    ERIC Educational Resources Information Center

    Sabarre, Amy; Gulino, Jacqueline

    2013-01-01

    What do a leaf blower, water hose, fan, and ice cubes have in common? Ask the students who participated in an integrative science, technology, engineering, and mathematics (I-STEM) education unit, "Wacky Weather," and they will tell say "fun and severe weather"--words one might not have expected! The purpose of the unit…

  12. Diagenetic cements in transgressive and regressive limestone members on the Stanton Limestone (Upper Pennsylvanian), northern midcontinent

    SciTech Connect

    Xiong, Bin; Heckel, P.H.; Gonzalez, L.A. . Dept. of Geology)

    1992-01-01

    Detailed cathodoluminescent microscopy reveals various types and phases of cement growth preserved in the two limestone members of the Stanton Limestone, which represents a complete cycle of sea level rise and fall during deposition. In the transgressive Captain Creek Limestone Member, early cements are mainly isopachous rims within brachiopods. In the regressive Stoner Limestone Member, early cements are both intergranula rand intragranular isopachous rims in oolitic and skeletal grainstones and in wackestones, as well as non-luminescent syntaxial overgrowths around echinoderm grains. The second phase of cementation in both members consists of luminescence void-filling blocky calcite and syntaxial overgrowths. The latest phase of cementation in both members comprises non-luminescent void-filling and/or replacement ferroan dolomite formed during burial. The early cements are more enriched in Fe and more enriched in Mg than in Sr. However, there seems to be little difference in trace elemental compositions between the transgressive and regressive limestones in general, although certain types of cements confined to one member fall into a relatively small field. The blocky calcites exhibit much higher Fe and Mn content than the early cements. The ferroan dolomite exhibits higher Fe and Mn concentration in the transgressive than in the regressive limestone. The greater abundance of marine cements in the regressive limestone is attributed to greater residence time in high-energy warm marine environments. Differences in Fe and Mn concentration between transgressive and regressive limestone cements are attributed to differences in redox conditions of diagenetic fluids controlled by the offshore Eudora Shale separating these two limestones.

  13. The Potential Use of Laser Ablation for Selective Cleaning of Indiana Limestone

    NASA Astrophysics Data System (ADS)

    Normandin, K. C.; Powers, L.; Slaton, D.; Scheffler, M. J.

    The aim of this investigation and conservation study was to examine and evaluate the laser ablation method as a practical technique for cleaning of Indiana limestone, a calcite-cemented stone widely used in historic structures throughout the United States. To this goal, a thorough petrographic characterization of the samples was performed prior to and following laser cleaning tests by Q-switched and short free running Nd:YAG lasers. The main optimization problem was the amber-gray appearance associated with the laser ablation by Q-switching lasers. Following the evaluation of such a cleaning result, two practicable solutions based on suitable pulse duration or wavelength selections were successfully demonstrated and then compared with different intervention protocols proposed. This chapter will show that through this case study, an understanding of effective uses of cleaning highly weathered Indiana limestone through the use of three types of Q-switched and short free running Nd:YAG lasers can be most effective in the removal from limestone of surface soiling and thick built-up carbon deposits ranging from 0.5 to 1mm in thickness. Case study evaluation methods included petrographic examination of composition, texture, and microstructure using optical microscopy and scanning electron microscopy performed on thin and polished sections of limestone sampled from six areas before and after cleaning. The microscopy studies were supplemented with energy-dispersive X-ray spectroscopy to characterize crystalline phases and track changes in chemistry.

  14. The effect of elevated temperature on the strength parameters of silica acid ester consolidated porous limestones

    NASA Astrophysics Data System (ADS)

    Pápay, Zita; Török, Ákos

    2013-04-01

    The porous limestone is one of the most widespread construction materials of the monuments in Central Europe, with emblematic buildings in Vienna, Bratislava, Budapest and many other cities of Austria, Slovakia, Czech Republic and Hungary. The restoration of these monuments very often requires the consolidation of the porous limestone material, where various types of consolidants are used to strengthen the highly weathered stone. Our research focused on the understanding of the behaviour of consolidated porous limestone when the material is subjected to higher temperatures. Test procedure included the preparation of cylindrical test specimens from the Miocene porous limestone which was followed by consolidation by four various types of silica acid ester. The samples after consolidation were heated to 300 and 600 °C in electric oven. The material properties such as ultrasonic pulse velocity, density were tested before and after the treatment. Indirect tensile strength (Brazilian test) was used to compare the strength parameters of non treated and consolidated samples. Silica acid ester treated samples after heating were also measured in terms of strength, density and ultrasonic pulse velocity. The results show that there are significant changes in strength of various pre-treated samples after heating indicating the sensitivity of the materials to temperature changes and accidental fire.

  15. Fly ash disposal in a limestone quarry

    SciTech Connect

    Peffer, J.R.

    1982-05-01

    Approximately 740 000 tons of eastern bituminous coal fly ash were deposited at the abandoned Zullinger limestone quarry from 1973-1980. The quarry extended below the water table and was not lined to isolate the ash from the aquifer. Long-term groundwater pollution has apparently not resulted.

  16. Crystalline marble beats limestone for fluegas desulfurization

    SciTech Connect

    1996-05-01

    NovaCon Energy Systems, Inc. (Bedford, NY) has developed an alternative to conventional limestone sorbents. The new process uses a class of marble, selected with a proprietary model. Recent pilot- and full-scale demonstrations in pulverized-coal (PC) and circulating fluidized bed (CFB) boilers suggest that these patented sorbents outperform conventional limestone for the simultaneous control of SOx, NOx, and particulates during the combustion of coal and sulfur-rich fuels, such as oil, mixed municipal waste and used tires. Dubbed thermally active marbles (TAMs), these sorbents are chemically identical to grainy limestone (whose main constituent is calcium carbonate or calcite). However, thanks to the increased pressures and temperatures experienced during their geologic history, these metamorphic minerals have a regular crystalline structure that offers some advantages in the combustion zone. TAMs, on the other hand, enjoy better calcium-utilization rates because upon heating, they cleave along inter- and intra-crystalline faces, continuously exposing fresh surfaces. By minimizing the self-extinguishment suffered by limestone sorbents, TAMs are effective over operating temperatures from 1,200 F to 2,800 F, which is 400 F higher than other calcium-based sorbents. This allows them to be injected closer to the burner or combustion grate to maximize residence time in the unit.

  17. Weatherizing America

    SciTech Connect

    Stewart, Zachary; Bergeron, T.J.; Barth, Dale; Qualis, Xavier; Sewall, Travis; Fransen, Richard; Gill, Tony

    2009-01-01

    As Recovery Act money arrives to expand home weatherization programs across the country, Zachary Stewart of Phoenix, Ariz., and others have found an exciting opportunity not only to start working again, but also to find a calling.

  18. Weatherizing America

    ScienceCinema

    Stewart, Zachary; Bergeron, T.J.; Barth, Dale; Qualis, Xavier; Sewall, Travis; Fransen, Richard; Gill, Tony

    2016-07-12

    As Recovery Act money arrives to expand home weatherization programs across the country, Zachary Stewart of Phoenix, Ariz., and others have found an exciting opportunity not only to start working again, but also to find a calling.

  19. Mineralogical characterization of the Shelburne marble and the Salem limestone

    SciTech Connect

    McGee, E.S.

    1989-01-01

    Samples of Shelburne marble and Salem limestone were selected to represent marbles and limestones used in buildings and monuments. The Royal variety of Shelburne marble is a white marble predominantly composed of calcite but has heterogeneously distributed gray inclusions. The select buff Salem limestone is a beige, homogeneous, fossiliferous limestone, predominantly composed of fragments of echinoderms and bryozoans. The author reports that both samples are appropriate test stones for the National Acid Precipitation Assessment Program stone exposure studies.

  20. Physicochemical characterizations of limestone for fluidized-bed coal combustion

    SciTech Connect

    Fuller, E.L. Jr.; Yoos, T.R. III; Walia, D.S.

    1981-05-01

    This study is an investigation of the physicochemical characteristics of three limestone samples, Quincy limestone (-20 + 60), Franklin limestone (-12 + 30), and Franklin limestone (-6 + 16), currently being tested at Oak Ridge National Laboratory for use in a fluidized-bed coal combustion unit. By correlating the chemistry, mineralogy, and surface area of these samples with empirical data obtained at Argonne National Laboratory, the sulfur capture ability and performance of these limestones can be loosely predicted. X-ray fluorescence and neutron activation analysis revealed a very high calcium content and very low concentrations of other elements in the three samples. X-ray diffraction patterns and petrographic examination of the limestone grains detected essentially no dolomite in the Quincy limestone or the fine Franklin limestone samples. The coarse Franklin limestone sample showed dolomite to be present in varying amounts up to maximum of 2.75%. Limited surface chemistry investigations of the samples were undertaken. Limestone and dolostone resources of the Tennessee Valley Authority region are widespread and abundant, and judged sufficient to meet industrial demand for many years. No problems are anticipated in securing limestone or dolostone supplies for a commercial fluidized-bed combustion plant in the Tennessee Valley Authority region. Transportation facilities and costs for limestone or dolostone will influence the siting of such a commercial fluidized-bed combustion plant. The most promising location in the Tennessee Valley Authority region at this time is Paducah, Kentucky.

  1. Changes in Zn speciation during soil formation from Zn-rich limestones

    NASA Astrophysics Data System (ADS)

    Jacquat, Olivier; Voegelin, Andreas; Juillot, Farid; Kretzschmar, Ruben

    2009-10-01

    In order to better understand the long-term speciation and fractionation of Zn in soils, we investigated three soils naturally enriched in Zn (237-864 mg/kg Zn) from the weathering of Zn-rich limestones (40-207 mg/kg Zn) using extended X-ray absorption fine structure (EXAFS) spectroscopy and sequential extractions. The analysis of bulk EXAFS spectra by linear combination fitting (LCF) indicated that Zn in the oolitic limestones was mainly present as Zn-containing calcite (at site Dornach), Zn-containing goethite (Gurnigel) and Zn-containing goethite and sphalerite (Liestal). Correspondingly, extraction of the powdered rocks with 1 M NH 4-acetate at pH 6.0 mobilized only minor fractions of Zn from the Gurnigel and Liestal limestones (<30%), but most Zn from the Dornach rock (81%). In the Dornach soil, part of the Zn released from the dissolving limestone was subsequently incorporated into pedogenic hydroxy-interlayered vermiculite (Zn-HIV, ˜30%) and Zn-containing kaolinite (˜30%) and adsorbed or complexed by soil organic and inorganic components (˜40%). The Gurnigel and Liestal soils contained substantial amounts of Zn-containing goethite (˜50%) stemming from the parent rock, smaller amounts (˜20%) of Zn-containing kaolinite (and possibly Zn-HIV), as well as adsorbed or complexed Zn-species (˜30%). In the soil from Liestal, sphalerite was only found in trace amounts, indicating its dissolution during soil formation. In sequential extractions, large percentages of Zn (˜55-85%) were extracted in recalcitrant extraction steps, confirming that Zn-HIV, Zn-containing kaolinite and Zn-containing goethite are highly resistant to weathering. These Zn-bearing phases thus represent long-term hosts for Zn in soils over thousands of years. The capability of these phases to immobilize Zn in heavily contaminated soils may however be limited by their uptake capacity (especially HIV and kaolinite) or their abundance in soil.

  2. Limestone reaction in calcium aluminate cement–calcium sulfate systems

    SciTech Connect

    Bizzozero, Julien Scrivener, Karen L.

    2015-10-15

    This paper reports a study of ternary blends composed of calcium aluminate cement, calcium sulfate hemihydrate and limestone. Compressive strength tests and hydration kinetics were studied as a function of limestone and calcium sulfate content. The phase evolution and the total porosity were followed and compared to thermodynamic simulation to understand the reactions involved and the effect of limestone on these binders. The reaction of limestone leads to the formation of hemicarboaluminate and monocarboaluminate. Increasing the ratio between sulfate and aluminate decreases the extent of limestone reaction.

  3. EPA compares lime, limestone FGD systems

    SciTech Connect

    Not Available

    1984-05-28

    According to a recent report by the EPA, flue gas desulfurization processes using lime require lower capital investments than limestone processes, and at low coal sulfur contents, annual revenue requirements are also lower. But this advantage disappears when coal sulfur content rises above 2%. A study of FGD systems performed by TVA evaluated absorber types, forced oxidation and the use of additives. The study compared processes with forced oxidation and landfill disposal, and found these have lower capital investments than processes without forced oxidation using pond disposal. Using additives in the limestone processes reduces both capital investment and annual revenue requirements. Adipic acid seems more efficient than MgO. Comparing absorber types, EPA found that for all systems, the TCA process was lowest in capital investment and annual revenue requirements.

  4. Limestone-gypsum flue gas desulfurization process

    SciTech Connect

    Kuroda, H.; Hashimoto, T.; Kanda, O.; Nishimura, M.; Nishimura, T.; Nozawa, S.

    1984-12-11

    A flue gas desulfurization process capable of producing a high purity gypsum and also making equipment employed as minimum as possible is provided, which process comprises the steps of cooling and dedusting flue gas containing SO /SUB x/ ; contacting the cooled gas with a slurry containing limestone to remove SO /SUB x/ by absorption and also form CaSO/sub 3/; controlling the pH of the resulting slurry and then blowing air therein to form gypsum; and separating gypsum from the resulting slurry. As a modification of the above process, the slurry of the above second absorption step is further fed to the above first cooling step where unreacted limestone and SO /SUB x/ are reacted to form CaSO/sub 3/.

  5. Biocalcifying Bacillus subtilis cells effectively consolidate deteriorated Globigerina limestone.

    PubMed

    Micallef, Roderick; Vella, Daniel; Sinagra, Emmanuel; Zammit, Gabrielle

    2016-07-01

    Microbially induced calcite precipitation occurs naturally on ancient limestone surfaces in Maltese hypogea. We exploited this phenomenon and treated deteriorated limestone with biocalcifying bacteria. The limestone was subjected to various mechanical and physical tests to present a statistically robust data set to prove that treatment was indeed effective. Bacillus subtilis conferred uniform bioconsolidation to a depth of 30 mm. Drilling resistance values were similar to those obtained for freshly quarried limestone (9 N) and increased up to 15 N. Treatment resulted in a high resistance to salt deterioration and a slow rate of water absorption. The overall percentage porosity of treated limestone varied by ±6 %, thus the pore network was preserved. We report an eco-friendly treatment that closely resembles the mineral composition of limestone and that penetrates into the porous structure without affecting the limestones' natural properties. The treatment is of industrial relevance since it compares well with stone consolidants available commercially.

  6. SANS investigation of the salt-crystallization- and surface-treatment-induced degradation on limestones of historic-artistic interest

    NASA Astrophysics Data System (ADS)

    Bottari, Cettina; Crisci, Gino Mirocle; Crupi, Vincenza; Ignazzitto, Valeria; La Russa, Mauro Francesco; Majolino, Domenico; Ricca, Michela; Rossi, Barbara; Ruffolo, Silvestro Antonio; Teixeira, Josè; Venuti, Valentina

    2016-08-01

    We present here a small-angle neutron scattering investigation on typical limestone widely used in the Baroque architecture of Modica (eastern Sicily). The aim was to correlate the salt weathering and, after that, consolidating (using nanolime as consolidant product) behaviour of the mesoscopic features observed in the experiment, with particular regard to the pore structure, which determines the interaction between surface and environmental/consolidating agents. Experimental results have been interpreted in terms of a fractal model that revealed successful in characterizing physical properties induced by treatment, in order to predict the behaviour of consolidated stone against salt weathering.

  7. The Helderberg limestone of central Pennsylvania

    USGS Publications Warehouse

    Reeside, John B.

    1917-01-01

    This paper presents the results of a study made during 1913, 1914, and 1915, while the writer was a student at Johns Hopkins University. The formations discussed have been studies in Maryland, New Jersey, and New York, and described with more or less detail, but concerning their occurrence in the intervening area in Pennsylvania little exact information has been available. The conflict in opinion as to the proper position and correlation of the Keyser limestone and as to the interpretation of some of the standard New York sections has made further data very desirable, and the present paper is an attempt to meet a part of the deficiency.

  8. Activities in Teaching Weather

    ERIC Educational Resources Information Center

    Tonn, Martin

    1977-01-01

    Presented is a unit composed of activities for teaching weather. Topics include cloud types and formation, simple weather instruments, and the weather station. Illustrations include a weather chart and instruments. A bibliography is given. (MA)

  9. Effects of salts on limestone dissolution rate in wet limestone flue gas desulfurization

    SciTech Connect

    Ukawa, Naohiko; Takashina, Toru; Oshima, Michio; Oishi, Tsuyoshi )

    1993-11-01

    To understand how the dissolution rate of limestone used for absorbent in a wet flue gas desulfurization plant is affected by the soluble salts formed from hydrogen chloride gas in flue gas as well as from the impurities contained in the used raw material limestone itself, various limestone slurries each supplemented with a single salt of CaCl[sub 2], MgCl[sub 2], NaCl, Na[sub 2]SO[sub 4] and MgSO[sub 4] were titrated with sulfuric acid. From the titration results the dissolution rate was found to vary greatly with the kind and the concentration of the salts with a general tendency to decrease in chloride solution but to increase in sulfate solutions. Based on this finding, the authors proposed a semi-empirical simplified model. The evaluated results using this model closely agreed with the measured values of the limestone dissolution rate both in single-salt solutions and mixed salt solutions. 9 refs., 8 figs., 1 tab.

  10. Adipic acid enhanced limestone flue gas desulfurization process - an assessment

    SciTech Connect

    Mobley, J.D.; Chang, J.C.S.

    1981-12-01

    Adipic acid, when used as an additive in a limestone FGD system, greatly increases both SO/sub 2/ removal and limestone utilization. Most existing limestone scrubbers would benefit from adipic acid addition without major process changes. No significant operating problems or adverse environmental impacts have been identified. The adipic acid enhanced system is economically attractive. Waste dibasic acids and glycolic acid appear to provide benefits similar to adipic acid at a lower cost.

  11. Limestone types used from the classic Karst region in Slovenia

    NASA Astrophysics Data System (ADS)

    Kramar, Sabina; Mirtič, Breda; Mladenović, Ana; Rožič, Boštjan; Bedjanič, Mojca; Kortnik, Jože; Šmuc, Andrej

    2014-05-01

    The paper presents a variety of limestones from the Karst Region that is one of the most interesting areas containing reserves of natural stones in Slovenia. The region is mainly composed of Cretaceous shallow-water limestone, with the most common type currently excavated being the rudist limestone of the Lipica Formation, which dates to the Santonian to Campanian. Limestones of this formation are mainly represented by a light grey, thick-bedded to massive Lipica limestone rich in (largely fragmented) rudists. Rudist shells can be either relatively well preserved (such as in Lipica Fiorito quarried limestone) or almost completely disintegrated and intensively endolitised (Lipica Unito quarried limestone). Beside the Lipica Formation, natural stone types have been excavated from two other formations or members in the Karst region: the Repen Formation (Repen and Kopriva limestones), and the Tomaj Limestone (dark, laminated limestone within the Lipica Formation). As documented, the region has been associated with the quarrying and processing of stone at least for over two thousand years, i.e. since the Roman period. Although a large number of quarries in all mentioned formations are documented in the Karst region, many are inactive nowadays. Some of the quarries are declared as geological monuments of national importance or officially protected as a natural monument. Karst limestones are considered the highest quality calcareous natural stones in Slovenia. They are characterised by high density, low water absorption and low open porosity; consequently they also exhibit high frost and salt resistance as well as high compressive and flexural strength. Besides in the Karst region and other parts of Slovenia, the Karst limestones were used in the construction of several important buildings and monuments in many other European Countries, and worldwide. Nowadays, they are most commonly used in the construction of façade cladding, pavements, window sills, staircases, indoor

  12. Importance of Radius of Influence and its Estimation in a Limestone Quarry

    NASA Astrophysics Data System (ADS)

    Soni, A. K.; Sahoo, L. K.; Ghosh, U. K.; Khond, M. V.

    2015-04-01

    Limestone mining at Lanjiberna limestone and dolomite quarry has created positive as well negative impacts on ground water. With further deepening of the mine, drawdown trend (negative effect) is observed and at the same time ground water recharge of the order of 4,527.48 m3/day, through mine pits (positive impact) is noticed. The aquifer present in the area is unconfined and mainly consists of weathered quartzite, phyllites, limestone and dolomite. To know the cumulative impact of mining on surroundings, the effective radius of influence (Re) for excavated mine area is calculated as 1,059 m. Here, it may be noted that three `concentric working pits' (Pit No. 2 & 6; Pit no 1 & 3 and Pit No 4 & 5) produces limestone at this mine and the pit-wise radius of influence (Ro) is estimated. Value of Ro for Pit-2 & 6 is 612.14 m; Pit-1 & 3 is 475 m and Pit-4 & 5 is 384.15 m. Its average i.e., Ro (for all three pits, cumulative) is estimated as 490 m. From this typical case study and estimation of Ro and Re values, it is concluded that the maximum and minimum value of overall impact/influence lies in between 0.49 and 1.05 km. These estimated values of `area of influence' are less compared to the whole mine lease area values. Local aquifer, which lies at shallower as well as at deeper depth had behaved consistently with respect to recharge and drawdown conditions. Thus, assessment of Ro and Re is extremely helpful for `integrated mine planning' to achieve targeted production, economically with minimum interruptions.

  13. Assessment of Rock Slope Stability in Limestone Quarries in the Tournai's Region (Belgium) Using Structural Data

    NASA Astrophysics Data System (ADS)

    Tshibangu, Jean-Pierre; Deloge, K. Pierre-Alexandre; Deschamps, Benoît; Coudyzer, Christophe

    The Tournais region is characterised by famous outcrops of carboniferous limestone which is mined out for cement and raw material production. The four main quarries found in the Region, i.e. Gaurain-Ramecroix, Milieu, Antoing and Lemay; are owned by the three main cement producers in Belgium: Italcimenti, Holcim and CBR. The global production of limestone is about 20 millions tons per year, giving big pits with depths up to 150 m. With the growth of the pits, the quarries are approaching each other leading to the problem of managing the reserves contained in the separating walls and their mechanical stability. The limestone deposit is composed of different seams having varying thickness, chemical com- position and even mechanical properties. The deposit has an overall horizontal dip and is intersected by two main sets of discontinuities with a spacing of about 10 m or less. It is also crossed by a set of east to west faults but the quarries are implanted in the in between areas, so to not be crossed by these faults. The layers and specially the shallow ones are characterised by a typical karstic weathering giving open or filled cavities. This paper presents the global work quarried out in order to study the stability of the Lemays quarry. First a description of the orientation and spacing of discontinuities is presented, and an attempt made to correlate to the development of weathering. Mechanical laboratory tests have been performed and a qualification of the rock mass assessed. A coupled approach is then presented using a mining planning analysis and mechanical simulation (i.e. Finite Element method).

  14. Weatherization and Intergovernmental Program - Portal to New Jobs in Home Weatherization (Green Jobs)

    SciTech Connect

    2010-04-01

    Expanding training opportunities in the weatherization of buildings will accelerate learning and provide a direct path for many Americans to find jobs in the clean energy field. The National Weatherization Training Portal (NWTP), which is now in the final stages of testing, features multi-media, interactive, self-paced training modules.

  15. Acid neutralization within limestone sand reactors receiving coal mine drainage.

    PubMed

    Watten, Barnaby J; Sibrell, Philip L; Schwartz, Michael F

    2005-09-01

    Pulsed bed treatment of acid mine drainage (AMD) uses CO2 to accelerate limestone dissolution and intermittent fluidization to abrade and carry away metal hydrolysis products. Tests conducted with a prototype of 60 L/min capacity showed effective removal of H+ acidity over the range 196-584 mg/L (CaCO3) while concurrently generating surplus acid neutralization capacity. Effluent alkalinity (mg/L CaCO3) rose with increases in CO2 (DC, mg/L) according to the model Alkalinity=31.22+2.97(DC)0.5, where DC was varied from 11-726 mg/L. Altering fluidization and contraction periods from 30s/30s to 10s/50s did not influence alkalinity but did increase energy dissipation and bed expansion ratios. Field trials with three AMD sources demonstrated the process is capable of raising AMD pH above that required for hydrolysis and precipitation of Fe3+ and Al3+ but not Fe2+ and Mn2+. Numerical modeling showed CO2 requirements are reduced as AMD acidity increases and when DC is recycled from system effluent.

  16. Acid neutralization within limestone sand reactors receiving coal mine drainage

    USGS Publications Warehouse

    Watten, B.J.; Sibrell, P.L.; Schwartz, M.F.

    2005-01-01

    Pulsed bed treatment of acid mine drainage (AMD) uses CO2 to accelerate limestone dissolution and intermittent fluidization to abrade and carry away metal hydrolysis products. Tests conducted with a prototype of 60 L/min capacity showed effective removal of H+ acidity over the range 196-584 mg/L (CaCO3) while concurrently generating surplus acid neutralization capacity. Effluent alkalinity (mg/L CaCO3) rose with increases in CO2 (DC, mg/L) according to the model Alkalinity = 31.22 + 2.97(DC)0.5, where DC was varied from 11-726 mg/L. Altering fluidization and contraction periods from 30 s/30 s to 10 s/50 s did not influence alkalinity but did increase energy dissipation and bed expansion ratios. Field trials with three AMD sources demonstrated the process is capable of raising AMD pH above that required for hydrolysis and precipitation of Fe3+ and Al3+ but not Fe2+ and Mn2+. Numerical modeling showed CO2 requirements are reduced as AMD acidity increases and when DC is recycled from system effluent. ?? 2005 Elsevier Ltd. All rights reserved.

  17. 3D mapping of water in oolithic limestone at atmospheric and vacuum saturation using X-ray micro-CT differential imaging

    SciTech Connect

    Boone, M.A.; De Kock, T.; Bultreys, T.; De Schutter, G.; Vontobel, P.; Van Hoorebeke, L.; Cnudde, V.

    2014-11-15

    Determining the distribution of fluids in porous sedimentary rocks is of great importance in many geological fields. However, this is not straightforward, especially in the case of complex sedimentary rocks like limestone, where a multidisciplinary approach is often needed to capture its broad, multimodal pore size distribution and complex pore geometries. This paper focuses on the porosity and fluid distribution in two varieties of Massangis limestone, a widely used natural building stone from the southeast part of the Paris basin (France). The Massangis limestone shows locally varying post-depositional alterations, resulting in different types of pore networks and very different water distributions within the limestone. Traditional techniques for characterizing the porosity and pore size distribution are compared with state-of-the-art neutron radiography and X-ray computed microtomography to visualize the distribution of water inside the limestone at different imbibition conditions. X-ray computed microtomography images have the great advantage to non-destructively visualize and analyze the pore space inside of a rock, but are often limited to the larger macropores in the rock due to resolution limitations. In this paper, differential imaging is successfully applied to the X-ray computed microtomography images to obtain sub-resolution information about fluid occupancy and to map the fluid distribution in three dimensions inside the scanned limestone samples. The detailed study of the pore space with differential imaging allows understanding the difference in the water uptake behavior of the limestone, a primary factor that affects the weathering of the rock. - Highlights: • The water distribution in a limestone was visualized in 3D with micro-CT. • Differential imaging allowed to map both macro and microporous zones in the rock. • The 3D study of the pore space clarified the difference in water uptake behavior. • Trapped air is visualized in the moldic

  18. [Analysis of trace elements in limestone for archeological functions

    SciTech Connect

    Blanc, A.; Holmes, L.; Harbottle, G.

    1998-12-31

    Numerous quarries in the Lutetian limestone formations of the Paris Basin provided stone for the building and the decoration of monuments from antiquity to the present. To determine the origin of stone used for masonry and sculptures in these monuments, a team of geologists and archaeologists has investigated 300 quarries and collected 2,300 samples. Petrographic and paleontologic examination of thin sections allows geologists to distinguish Lutetian limestones from Jurassic and Cretaceous limestones. Geologists also seek to formulate hypotheses regarding the origin of Lutetian limestones used for building and sculpture in the Paris region. In the search for the sources of building and sculptural stone, the analytical methods of geologists are limited because often several quarries produce the same lithofacies. A new tool is now available, however, to attack questions of provenance raised by art historians. Because limestones from different sources have distinctive patterns of trace-element concentrations, compositional analysis by neutron activation allows one to compare building or sculptural stone from one monument with stone from quarries or other monuments. This analytical method subjects a powdered limestone sample to standard neutron activation analysis procedures at Brookhaven National Laboratory. With the help of computer programs, the compositional fingerprints of Lutetian limestones can be determined and stored in a database. The limestone database contains data for approximately 2,100 samples from monuments, sculptures and quarries. It is particularly rich in samples from the Paris Basin.

  19. STEAM INJECTION INTO FRACTURED LIMESTONE AT LORING AIR FORCE BASE

    EPA Science Inventory

    A research project on steam injection for the remediation of spent chlorinated solvents from fractured limestone was recently undertaken at the former Loring AFB in Limestone, ME. Participants in the project include the Maine Department of Environmental Protection, EPA Region I,...

  20. [Reactivity of the limestone in wet flue gas desulfurization].

    PubMed

    Zhu, Tian-le; Li, Yao; Ling, Xuan; Liu, Hong-ju; Xu, Feng-gang; Liu, Han-qiang

    2005-11-01

    On the basis of the analysis of chemical components of the natural limestones from different deposits in China, the pore structures of the typical limestones, with the different CaCO3 content, were examined. The reactivity of the limestones was investigated by sulfuric acid titration and gas-liquid absorption methods. The research results showed that the specific surface area of the natural limestones studied in this work was about 1.8 m2/g. It was seen that the pH of the limestone slurry rapidly decreased and then back up when the sulfuric acid was added. The higher the CaCO3 content was, or the smaller the particle size was, the larger the pH back-up rate was, and similarly the faster the SO2 concentration of the reactor outlet increased. The Reactivity of the limestone obtained by the sulfuric acid titration had the same features as that obtained by the gas liquid absorption. Compared with the specific surface area, the CaCO3 content had more effect on the reactivity of the limestones. The particle size of the limestones had a significant effect on the reactivity when the particle size was relatively large, that is less than 300-360 mesh, vice versa.

  1. Microfacies and diagenesis of the reefal limestone, Callovian Tuwaiq Mountain Limestone Formation, central Saudi Arabia

    NASA Astrophysics Data System (ADS)

    EL-Sorogy, Abdelbaset S.; Almadani, Sattam A.; Al-Dabbagh, Mohammad E.

    2016-03-01

    In order to document the microfacies and diagenesis of the reefal limestone in the uppermost part of the Callovian Tuwaiq Mountain Limestone Formation at Khashm Al-Qaddiyah area, central Saudi Arabia, scleractinian corals and rock samples were collected and thin sections were prepared. Coral framestone, coral floatstone, pelloidal packstone, bioclastic packstone, bioclastic wacke/packstone, algal wackestone and bioclastic foraminiferal wacke/packstone were the recorded microfacies types. Cementation, recrystallization, silicification and dolomitization are the main diagenetic alterations affected the aragonitic skeletons of scleractinian corals. All coral skeletons were recrystallized, while some ones were dolomitized and silicified. Microfacies types, as well as the fossil content of sclearctinian corals, bivalves, gastropods, brachiopods and foraminifera indicated a deposition in environments ranging from shelf lagoon with open circulation in quiet water below wave base to shallow reef flank and organic build up for the uppermost reefal part of the Tuwaiq Formation in the study area.

  2. Faunas of Mississippian oolitic limestones: Evidence from Salem Limestone, southern Indiana

    SciTech Connect

    Feldman, H.R. )

    1989-08-01

    In the Salem Limestone of southern Indiana, a correlation exists between the faunal assemblage and abundance of grains with superficial oolitic coatings in grainstones. Coarse, poorly sorted fossiliferous grainstones are dominated by an echinoderm-bryozoan-brachiopod assemblage of fossils with few mollusks. The presence of large whole fossils, such as articulated crinoid calyces, suggest limited transport of skeletal components. Grainstones, dominated by grains with superficial coatings, and foraminifers tend to contain a diverse mollusk-dominated assemblage of gastropods, bivalves, rostroconchs, chitins, and scaphopods. These fossils are disarticulated, but generally are not fragmented even though many of them are thin and delicate. Echinoderms, brachiopods, and bryozoans are repsented in the mollusk-domdinated assemblage almost exclusively by well-rounded and coated fragments, suggesting that they are not in situ. The presence of similar molluscan assemblages in other Mississippian coated-grain grainstones from Alabama (the Monteagle Limestone) and Oklahoma (an unnamed limestone) indicates that the assemblage may have been wide-spread. Mississippian grainstones dominated by oolites (which are not prominent in the Salem) generally have very few fossils.

  3. Field trial of a pulsed limestone diversion well

    USGS Publications Warehouse

    Sibrell, Philip L.; Denholm, C.; Dunn, Margaret

    2013-01-01

    The use of limestone diversion wells to treat acid mine drainage (AMD) is well-known, but in many cases, acid neutralization is not as complete as would be desired. Reasons for this include channeling of the water through the limestone bed, and the slow reaction rate of the limestone gravel. A new approach to improve the performance of the diversion well was tested in the field at the Jennings Environmental Education Center, near Slippery Rock, PA. In this approach, a finer size distribution of limestone was used so as to allow fluidization of the limestone bed, thus eliminating channeling and increasing particle surface area for faster reaction rates. Also, water flow was regulated through the use of a dosing siphon, so that consistent fluidization of the limestone sand could be achieved. Testing began late in the summer of 2010, and continued through November of 2011. Initial system performance during the 2010 field season was good, with the production of net alkaline water, but hydraulic problems involving air release and limestone sand retention were observed. In the summer of 2011, a finer size of limestone sand was procured for use in the system. This material fluidized more readily, but acid neutralization tapered off after several days. Subsequent observations indicated that the hydraulics of the system was compromised by the formation of iron oxides in the pipe leading to the limestone bed, which affected water distribution and flow through the bed. Although results from the field trial were mixed, it is believed that without the formation of iron oxides and plugging of the pipe, better acid neutralization and treatment would have occurred. Further tests are being considered using a different hydraulic configuration for the limestone sand fluidized bed.

  4. Limestone dissolution in flue gas scrubbing: Effect of sulfite

    SciTech Connect

    Gage, C.L.; Rochelle, G.T. )

    1992-07-01

    Batch limestone dissolution experiments were carried out in a pH stat apparatus at 55 C with CO{sub 2} sparging and dissolved sulfite. Particle size distribution, utilization, sulfite in solution, limestone type, and the approach to calcite equilibrium were all found to contribute to the limestone reactivity. In the absence of sulfite, limestone dissolution was controlled solely by mass transfer. For a given stone under mass transfer control, film thickness was found to be independent of pH. The dissolution rate in the presence of sulfite was controlled by a combined surface kinetics/mass transfer regime. SEM micrographs supported this conclusion. A surface rate correlation was developed which accounted for observed inhibition by an inverse dependence on calcium sulfite concentration at the limestone dependence on calcium sulfite concentration at the limestone surface. While the form of the rate expression was applicable to all stones, the surface rate constant was stone dependent. A computer code which accounted for mass transfer with surface kinetics was tested against experimental observations of four limestone types. Changes in pH and the concentrations of calcium, carbonate, sulfite, sulfate, and adipic acid were accurately modeled.

  5. Geology of Vanport limestone (Pennsylvanian) in Elk County, Pennsylvania

    SciTech Connect

    Kuntz, T.J.

    1987-09-01

    The northernmost exposures of the Vanport limestone appear in Elk and southern McKean Counties, Pennsylvania. The Vanport limestone is structurally preserved in N45/sup 0/-50/sup 0/E trending synclinal folds. Surface exposures are almost all incomplete due to erosion. Drill-hole data assisted in defining areas of nondeposition within Elk County, variations in thickness, and erosional loss by channeling. The Vanport limestone thins to the southeast within Elk County and probably changes from limestone to a shaly limestone (transition zone) and then to shale. Analysis of 70 limestone samples indicated an average insoluble-residue content of 11.4%. The insoluble residue, mainly clay, increases toward the southeast, the direction of paleoshoreline and source of terrigenous sediments. A lack of quartz grains suggests a lack of detrital input from the source area. A study of the vertical variation of the total insoluble-residue content displayed an increase at the bottoms and tops of the stratigraphic section, mirroring the transgressive-regressive phases of the Vanport sea. The majority of allochems were skeletal material in a micritic matrix. Most abundant were mollusks, followed by forams, brachiopods, echinoderms, ostracods, and bryozoans. Composita brachiopods and pseudopunctate and/or punctate brachiopods inhabited offshore stillstand and nearshore transgressive-regressive environments, respectively. Other fossil assemblages displayed spatial and temporal variation. A darker matrix color occurred in stratigraphic sections closer to the paleoshoreline, due to higher clay and organic content. More offshore stratigraphic sections of the limestone were noticeably lighter in color.

  6. United Arab Emirates limestones: impact of petrography on thermal behavior

    NASA Astrophysics Data System (ADS)

    Alaabed, Sulaiman; Soltan, Abdel Monem; Abdelghany, Osman; Amin, Bahaa Eldin Mahmoud; El Tokhi, Mohamed; Khaleel, Abbas; Musalim, Abdullah

    2014-12-01

    The thermal behavior of selected limestones from representative localities of the United Arab Emirates is investigated for their suitability for soft-burnt lime production. The limestone samples were collected from the Ghalilah, Musandam, Shauiba, Muthaymimah, Dammam and Asmari formations. The samples were characterized for petrography, mineral and chemical composition, together with physico-mechanical characteristics. Investigative methods included transmitted light microscopy (TLM), cathodoluminescence (CLM) and scanning electron microscopy (SEM), as well as X-ray micro-tomography (μ-CT), XRD, XRF and Archimedes method. The limestone samples were fired in an electrical muffle furnace for 0.25, 0.5, 1 and 2 hours at 800, 900, 1,000 and 1,100 °C. After firing the lime grains were tested to determine their hydration rate and microfabric. The Ghalilah and Musandam limes show the lowest and highest maximum hydration rates, respectively, due mainly to the impure nature of the former, and the smaller lime crystallites and dominance of post-calcination micro-cracks of the latter. The Dammam and Asmari limes preserve a "ghost" microfabric of the original limestone. Higher allochem contents impose lower activation energy requirements for calcination, which implies earlier calcination of the allochems. The Musandam, Shauiba and Muthaymimah limestones may be useful for the production of reactive soft-burnt lime under the applied firing conditions, however, the Dammam and Asmari limestones need more advanced calcination conditions than the applied ones. The Ghalilah limestone was found to be unsuitable for the production of lime.

  7. Forecasting the Weather.

    ERIC Educational Resources Information Center

    Bollinger, Richard

    1984-01-01

    Presents a computer program which predicts the weather based on student input of such weather data as wind direction and barometric pressure. Also provides procedures for several hands-on, weather-related activities. (JN)

  8. Weather in the News.

    ERIC Educational Resources Information Center

    Markle, Sandra

    1989-01-01

    A discussion of TV weather forecasting introduces this article which features several hands-on science activities involving observing, researching, and experimenting with the weather. A reproducible worksheet on the reliability of weather forecasts is included. (IAH)

  9. EXTERIOR OVERVIEW, LOOKING NORTH, OF THIS 400' DEEP LIMESTONE QUARRY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    EXTERIOR OVERVIEW, LOOKING NORTH, OF THIS 400' DEEP LIMESTONE QUARRY PIT ("THE OLD PIT") WITH LEDGE PREPARED FOR LIMESTONE EXTRACTION. AN ELEVEN-HOLE SHOT WILL DISLODGE APPROXIMATELY 25,000 TONS OF LIMESTONE WHICH, AFTER LOADING AND CRUSHING, WILL BE USED FOR ROAD CONSTRUCTION. THE CALERA QUARRY IS ONE OF FOUR ACTIVE VULCAN MATERIALS COMPANY QUARRIES IN THE DISTRICT. VULCAN MATERIALS, A FORTUNE 500 FIRM, ESTABLISHED IN BIRMINGHAM IN 1906 AS BIRMINGHAM SLAG COMPANY, VULCAN MATERIALS IS THE NATION'S FOREMOST PRODUCER OF CONSTRUCTION AGGREGATE AND A LEADING CHEMICALS MANUFACTURER - Vulcan Material Company, Calera Quarry, 1614 Highway 84, Calera, Shelby County, AL

  10. EXTERIOR OVERVIEW, LOOKING NORTH, OF THIS 400' DEEP LIMESTONE QUARRY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    EXTERIOR OVERVIEW, LOOKING NORTH, OF THIS 400' DEEP LIMESTONE QUARRY PIT ('THE OLD PIT') WITH LEDGE PREPARED FOR LIMESTONE EXTRACTION. AN ELEVEN-HOLE SHOT WILL DISLODGE APPROXIMATELY 25,000 TONS OF LIMESTONE WHICH, AFTER LOADING AND CRUSHING, WILL BE USED FOR ROAD CONSTRUCTION. THE CALERA QUARRY IS ONE OF FOUR ACTIVE VULCAN MATERIALS COMPANY QUARRIES IN THE DISTRICT. VULCAN MATERIALS, A FORTUNE 500 FIRM, ESTABLISHED IN BIRMINGHAM IN 1906 AS BIRMINGHAM SLAG COMPANY, VULCAN MATERIALS IS THE NATION'S FOREMOST PRODUCER OF CONSTRUCTION AGGREGATE AND A LEADING CHEMICALS MANUFACTURER. - Vulcan Material Company, Calera Quarry, 1614 Highway 84, Calera, Shelby County, AL

  11. Accelerated Carbonate Dissolution as a CO2 Separation and Sequestration Strategy

    SciTech Connect

    Caldeira, K G; Knauss, K G; Rau, G H

    2004-02-18

    process is geochemically equivalent to continental and marine carbonate weathering which will otherwise naturally consume anthropogenic CO{sub 2}, but over many millennia (e.g. [7,8,9]). We identify the enhanced form of this process as Accelerated Weathering of Limestone or accelerated carbonate dissolution. Previously, it has been shown that accelerated carbonate dissolution can effectively convert a significant fraction of US CO{sub 2} emissions to long-term storage as bicarbonate in the ocean, while avoiding or possibly reversing environmental impacts associated with either the ongoing passive or the proposed active injection of CO{sub 2} into the ocean [6,10]. Being analogous to the widespread use of wet limestone to desulfurize flue gas, accelerated carbonate dissolution reactors could be retrofitted to many existing coastal power plants at a typical cost estimated to be $20-$30/tonne CO{sub 2} mitigated [5,11]. This paper further explores limestone availability, cost, transportation, and reaction kinetics as well as ocean and environmental impacts, and the overall economics and practicality of accelerated carbonate dissolution CO{sub 2} mitigation.

  12. Limestone - A Crucial and Versatile Industrial Mineral Commodity

    USGS Publications Warehouse

    Bliss, James D.; Hayes, Timothy S.; Orris, Greta J.

    2008-01-01

    Limestone, as used by the minerals industry, is any rock composed mostly of calcium carbonate (CaCO3). Although limestone is common in many parts of the United States, it is critically absent from some. Limestone is used to produce Portland cement, as aggregate in concrete and asphalt, and in an enormous array of other products, making it a truly versatile commodity. Portland cement is essential to the building industry, but despite our Nation's abundance of limestone, there have been cement shortages in recent years. These have been caused in part by a need to find new areas suitable for quarrying operations. To help manage our Nation's resources of such essential mineral commodities, the U.S. Geological Survey (USGS) provides crucial data and scientific information to industry, policymakers, and the public.

  13. LUTETIAN LIMESTONES IN THE PARIS REGION: PETROGRAPHIC AND COMPOSITIONAL EXAMINATION

    SciTech Connect

    BLANC,A.; HOLMES,L.L.; HARBOTTLE,G.

    1998-06-11

    Stone for building and decorating monuments in the Paris Basin from antiquity to the present came from numerous quarries in the Lutetian limestone formations of the region. To identify specific-stone sources used for masonry and sculptures in these monuments, a team of geologists and archaeologists has investigated 300 quarries and collected 2,300 limestone samples for study in a collaborative effort by geologists and chemists. Petrographic and paleontologic examinations of thin sections enable geologists to distinguish the Tertiary Lutetian limestones from similar stone in Jurassic and Cretaceous strata. The methods of the geologist have been supplemented by those of the chemist whose compositional studies by neutron activation analysis can differentiate among the fine-grained upper Lutetian limestones extracted from specific ancient quarries.

  14. Lutetian limestones in the Paris region: Petrographic and compositional examination

    SciTech Connect

    Blanc, A.; Holmes, L.L.; Harbottle, G.

    1998-12-31

    Stone for building and decorating monuments in the Paris Basin from antiquity to the present came from numerous quarries in the Lutetian limestone formations of the region. To identify specific stone sources used for masonry and sculptures in these monuments, a team of geologists and archaeologists have investigated 300 quarries and collected 2,300 limestone samples for study in a collaborative effort by geologists and chemists. Petrographic and paleontologic examinations of thin sections enable geologists to distinguish the Tertiary Lutetian limestones from similar stone in Jurassic and Cretaceous strata. The methods of the geologist have been supplemented by those of the chemistry whose compositional studies by neutron activation analysis can differentiate among the fine-grained upper Lutetian limestones extracted from specific ancient quarries.

  15. Limestone and bronze "Mississippi River Crossing" Bridge plaque located at ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Limestone and bronze "Mississippi River Crossing" Bridge plaque located at North corner of Administration Building site - Huey P. Long Bridge, Administration Building, 5100 Jefferson Highway, Jefferson, Jefferson Parish, LA

  16. 1. SOUTH FACADE. CONSTRUCTED (ca. 1895) OF INDIGENOUS LIMESTONE AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. SOUTH FACADE. CONSTRUCTED (ca. 1895) OF INDIGENOUS LIMESTONE AND USED AS LOCKPORTS CENTRAL HIGH SCHOOL FOR MORE THAN SIXTY YEARS. - Lockport Historic District, Central High School, Lockport, Will County, IL

  17. Facies patterns and depositional environments of Palaeozoic cephalopod limestones

    NASA Astrophysics Data System (ADS)

    Wendt, J.; Aigner, T.

    1985-07-01

    In the eastern Anti-Atlas (Morocco) a platform and basin topography was established during the late Devonian, probably as a result of early Variscan tensional tectonics. Cephalopod limestones were deposited on shallow pelagic platforms, platform slopes and shallow, slowly subsiding basins. On the platform a transition from land areas into nearshore quartzose brachiopod coquinas, crinoidal limestones, condensed cephalopod limestones and finally into nodular limestones is observed. The latter often become disintegrated into incipient debris flows which pass into nodular limestone/marl alternations of a shallow basin. Deeper basins with shale sedimentation lack cephalopod limestones. Similar facies types also occur in the late Devonian of the Montagne Noire (France), Rheinisches Schiefergebirge (West Germany), Moravian Karst (Czechoslovakia), Holy Cross Mountains (Poland) and in the early Carboniferous of the Cantabrian Mountains (Spain). Due to strong late Variscan compressional tectonics and limited outcrops, detailed facies patterns could not be mapped in these regions, but the same facies types as in the eastern Anti-Atlas suggest similar coast/platform, slope and shallow basin topographies. During cephalopod limestone deposition water depth on the platforms was in the order of several tens to about one hundred metres, as is inferred from repeated subaerial exposures and distinctive depositional and faunal/floral features. Water depth in the adjacent shallow basins might have reached several hundreds of metres. Cephalopod limestones represent a typical stage in the evolution of geosynclines, characterized by extremely low sedimentation rates (1-5 m m.y. -1). This stage is preceded by deposition of thick neritic clastics and/or carbonates and is succeeded by deposition of deep-water clastics or flysch.

  18. [Enrichment and release of uranium during weathering of sedimentary rocks in Wujiang catchments].

    PubMed

    Song, Zhao-Liang; Liu, Cong-Qiang; Han, Gui-Lin; Wang, Zhong-Liang; Yang, Cheng; Liu, Zhan-Min

    2006-11-01

    Thirteen weathering profiles of typical rocks such as limestone, dolomitic limestone, dolomite, sillcalite, black shale and purple sandrock from Wujiang catchments were selected for discussing enrichment and release behavior of uranium (U) during rock weathering, and studying its impact on riverine U distribution in the catchments during weathering of these rocks with methods of correlation analysis and mass balance calculation. The purpose of this study is to improve our understanding on biogechemical cycling of U and set a basis for catchment protection against U pollution. The results show that the enrichment extent of U in soils from the Wujiang catchments is usually higher than that of upper continental crust (UCC), China soil (CS) and world soil (WS). The ability of enrichment and release of U is partly controlled by content of U in bedrocks, contents and adsorption ability of clay minerals and Fe-oxides/hydroxides in weathering profiles. Our study also reveals that release of U mainly from weathering of limestone and partly from weathering of dolomite and clastic rocks exerts an important control on riverine U distribution.

  19. Teaching Weather Concepts.

    ERIC Educational Resources Information Center

    Sebastian, Glenn R.

    Ten exercises based on the weather map provided in the national newspaper "U.S.A. Today" are used to teach intermediate grade students about weather. An overview describes the history of "U.S.A. Today," the format of the newspaper's weather map, and the map's suitability for teaching weather concepts. Specific exercises, which are briefly…

  20. Fun with Weather

    ERIC Educational Resources Information Center

    Yildirim, Rana

    2007-01-01

    This three-part weather-themed lesson for young learners connects weather, clothing, and feelings vocabulary. The target structures covered are: asking about the weather; comparing weather; using the modal auxiliary, should; and the question word, when. The lessons utilize all four skills and include such activities as going outside, singing,…

  1. Weather in Your Life.

    ERIC Educational Resources Information Center

    Kannegieter, Sandy; Wirkler, Linda

    Facts and activities related to weather and meteorology are presented in this unit. Separate sections cover the following topics: (1) the water cycle; (2) clouds; (3) the Beaufort Scale for rating the speed and force of wind; (4) the barometer; (5) weather prediction; (6) fall weather in Iowa (sleet, frost, and fog); (7) winter weather in Iowa…

  2. Linear Accelerators

    NASA Astrophysics Data System (ADS)

    Sidorin, Anatoly

    2010-01-01

    In linear accelerators the particles are accelerated by either electrostatic fields or oscillating Radio Frequency (RF) fields. Accordingly the linear accelerators are divided in three large groups: electrostatic, induction and RF accelerators. Overview of the different types of accelerators is given. Stability of longitudinal and transverse motion in the RF linear accelerators is briefly discussed. The methods of beam focusing in linacs are described.

  3. Economic evaluation and comparison of alternative limestone-scrubbing options

    SciTech Connect

    Burnett, T.A.; Torstrick, R.L.; Sudhoff, F.A.

    1982-01-01

    The preliminary-grade economics (accuracy: -15%, +30%) of various alternative limestone scrubbing options (absorber type, with and without forced oxidation, and with and without adipic acid enhancement) are examined using the current design and economic premises established for the continuing series of economic evaluations performed by TVA for EPA. The economics are projected using the Shawnee lime/limestone computer model, which is based on long-term operating data from the EPA Alkali Scrubbing Test Facility at the TVA Shawnee Steam Plant near Paducah, Kentucky. The capital investment for the base-case limestone scrubbing process (500 MW, 3.5% sulfur coal, 1979 NSPS, spray tower, forced oxidation, landfill) is $206/kW. The first-year and levelized annual revenue requirements are 10.59 and 15.09 mills/kWh respectively. Costs for the equivalent limestone scrubbing process using a Turbulent Contact Absorber (TCA) are lower while those for the venturi - spray tower absorber are higher. The forced-oxidation landfill disposal option has a lower capital investment than the unoxidized pond disposal option for all cases studied; however, the first-year and levelized annual revenue requirements are slightly higher for the forced-oxidation landfill process for most coal applications. For the spray tower limestone process to achieve a specified SO/sub 2/ removal efficiency, it is more economical to increase the limestone stoichiometry and minimize the absorber L/G. The use of adipic acid or possibly dibasic acid (DBA) as an additive to enhance SO/sub 2/ removal in the limestone scrubbing process is an economically attractive option. The use of adipic acid remains economically attractive even if both a high unit cost and a high degradation factor for adpic acid are assumbed.

  4. Landslides as weathering reactors; links between physical erosion and weathering in rapidly eroding mountain belts

    NASA Astrophysics Data System (ADS)

    Emberson, R.; Hovius, N.; Galy, A.

    2014-12-01

    The link between physical erosion and chemical weathering is generally modelled with a surface-blanketing weathering zone, where the supply of fresh minerals is tied to the average rate of denudation. In very fast eroding environments, however, sediment production is dominated by landsliding, which acts in a stochastic fashion across the landscape, contrasting strongly with more uniform denudation models. If physical erosion is a driver of weathering at the highest erosion rates, then an alternative weathering model is required. Here we show that landslides can be effective 'weathering reactors'. Previous work modelling the effect of landslides on chemical weathering (Gabet 2007) considered the fresh bedrock surfaces exposed in landslide scars. However, fracturing during the landslide motion generates fresh surfaces, the total surface area of which exceeds that of the exposed scar by many orders of magnitude. Moreover, landslides introduce concavity into hillslopes, which acts to catch precipitation. This is funnelled into a deposit of highly fragmented rock mass with large reactive surface area and limited hydraulic conductivity (Lo et al. 2007). This allows percolating water reaction time for chemical weathering; any admixture of macerated organic debris could yield organic acid to further accelerate weathering. In the South island of New Zealand, seepage from recent landslide deposits has systematically high solute concentrations, far outstripping concentration in runoff from locations where soils are present. River total dissolved load in the western Southern Alps is highly correlated with the rate of recent (<35yrs) landsliding, suggesting that landslides are the dominant locus of weathering in this rapidly eroding landscape. A tight link between landsliding and weathering implies that localized weathering migrates through the landscape with physical erosion; this contrasts with persistent and ubiquitous weathering associated with soil production. Solute

  5. Biogeochemistry of plant-soil system in a limestone area: A case study of Mt. Kinsho-zan, Gifu prefecture, central Japan

    NASA Astrophysics Data System (ADS)

    Ueno, S.; Sugitani, K.; Ono, M.

    2010-12-01

    concentrations of CaO are about 10 times higher than those in soils from the sandstone-mudstone area. Compared to the sandstone-mudstone area, 13 elements in soils and 10 elements in leaves from the limestone area have higher concentrations. Soils from the limestone area contain higher concentrations of MnO, Ni, and Zn than those from the sandstone-mudstone area. Concentrations of these elements in leaves, in contrast, tend to be lower in the limestone area than in the sandstone-mudstone area; Si shows the opposite result. Both soils and leaves in the limestone area contain more Ca and P than those in the sandstone-mudstone area. In the limestone area, CaO/TiO2 and P2O5/TiO2 ratios in soils are lower than those in rocks, suggesting leaching of Ca and P, whereas the upper soil samples have higher values than the lower soil samples. Calcareous dust transported from a nearby excavated research field may have been deposited on the surface layer. Zr/TiO2 ratios in soils are lower than those in rocks, suggesting that materials with low Zr/TiO2 values have been transported into soils. The soils in the limestone area likely contain significant amounts of allochthonous materials, in addition to the weathering products of parental rocks.

  6. Pilot weather advisor

    NASA Technical Reports Server (NTRS)

    Kilgore, W. A.; Seth, S.; Crabill, N. L.; Shipley, S. T.; Graffman, I.; Oneill, J.

    1992-01-01

    The results of the work performed by ViGYAN, Inc., to demonstrate the Pilot Weather Advisor cockpit weather data system using a broadcast satellite communication system are presented. The Pilot Weather Advisor demonstrated that the technical problems involved with transmitting significant amount of weather data to an aircraft in-flight or on-the-ground via satellite are solvable with today's technology. The Pilot Weather Advisor appears to be a viable solution for providing accurate and timely weather information for general aviation aircraft.

  7. Modifying the properties of finely ground limestone by tumbling granulation

    NASA Astrophysics Data System (ADS)

    Macho, Oliver; Eckert, Maroš; Tomášová, Barbora; Peciar, Peter; Ščasný, Martin; Fekete, Roman; Peciar, Marián

    2016-06-01

    Calcium carbonate in the form of finely ground limestone is a material that has found its application in a wide range of industries, in the chemical, rubber, agricultural, and paper industries, is used for desulfurization of boilers and other. In civil engineering, ground limestone is used for the production of building materials, plaster and mortar mixtures, as a filler in concrete mixtures, in road construction, and as an essential component of mastic asphalt. This paper deals with examining the modification of the properties of finely ground limestone by the tumbling agglomeration method. It has been shown that the components of concrete with a round grain have a positive effect on the pumping of concrete in comparison with an elongated grain or the rough surface of crushed stone. The experiments will be carried out on a granulation plate using a variety of granulation liquid. The agglomerates and their properties were compared with untreated finely ground limestone, with a focus on detecting changes in compressibility, density and particle size. The output of this paper is a description and graphical representation of the changes in the properties of ground limestone before and after the agglomeration process.

  8. Can Accelerators Accelerate Learning?

    NASA Astrophysics Data System (ADS)

    Santos, A. C. F.; Fonseca, P.; Coelho, L. F. S.

    2009-03-01

    The 'Young Talented' education program developed by the Brazilian State Funding Agency (FAPERJ) [1] makes it possible for high-schools students from public high schools to perform activities in scientific laboratories. In the Atomic and Molecular Physics Laboratory at Federal University of Rio de Janeiro (UFRJ), the students are confronted with modern research tools like the 1.7 MV ion accelerator. Being a user-friendly machine, the accelerator is easily manageable by the students, who can perform simple hands-on activities, stimulating interest in physics, and getting the students close to modern laboratory techniques.

  9. PARTICLE ACCELERATOR

    DOEpatents

    Teng, L.C.

    1960-01-19

    ABS>A combination of two accelerators, a cyclotron and a ring-shaped accelerator which has a portion disposed tangentially to the cyclotron, is described. Means are provided to transfer particles from the cyclotron to the ring accelerator including a magnetic deflector within the cyclotron, a magnetic shield between the ring accelerator and the cyclotron, and a magnetic inflector within the ring accelerator.

  10. Winter Weather Checklists

    MedlinePlus

    ... About CDC.gov . Natural Disasters and Severe Weather Earthquakes Being Prepared Emergency Supplies Home Hazards Indoor Safety ... Matters What's New Preparation & Planning Disasters & Severe Weather Earthquakes Extreme Heat Floods Hurricanes Landslides Tornadoes Tsunamis Volcanoes ...

  11. Winter Weather: Frostbite

    MedlinePlus

    ... About CDC.gov . Natural Disasters and Severe Weather Earthquakes Being Prepared Emergency Supplies Home Hazards Indoor Safety ... Matters What's New Preparation & Planning Disasters & Severe Weather Earthquakes Extreme Heat Floods Hurricanes Landslides Tornadoes Tsunamis Volcanoes ...

  12. Winter Weather: Outdoor Safety

    MedlinePlus

    ... About CDC.gov . Natural Disasters and Severe Weather Earthquakes Being Prepared Emergency Supplies Home Hazards Indoor Safety ... Matters What's New Preparation & Planning Disasters & Severe Weather Earthquakes Extreme Heat Floods Hurricanes Landslides Tornadoes Tsunamis Volcanoes ...

  13. Winter Weather Emergencies

    MedlinePlus

    Severe winter weather can lead to health and safety challenges. You may have to cope with Cold related health problems, including ... there are no guarantees of safety during winter weather emergencies, you can take actions to protect yourself. ...

  14. American Weather Stories.

    ERIC Educational Resources Information Center

    Hughes, Patrick

    Weather has shaped United States' culture, national character and folklore; at times it has changed the course of history. The seven accounts compiled in this publication highlight some of the nation's weather experiences from the hurricanes that threatened Christopher Columbus to the peculiar run of bad weather that has plagued American…

  15. Aviation weather services

    NASA Technical Reports Server (NTRS)

    Sprinkle, C. H.

    1983-01-01

    The primary responsibilities of the National Weather Service (NWS) are to: provide warnings of severe weather and flooding for the protection of life and property; provide public forecasts for land and adjacent ocean areas for planning and operation; and provide weather support for: production of food and fiber; management of water resources; production, distribution and use of energy; and efficient and safe air operations.

  16. Weather Fundamentals: Meteorology. [Videotape].

    ERIC Educational Resources Information Center

    1998

    The videos in this educational series, for grades 4-7, help students understand the science behind weather phenomena through dramatic live-action footage, vivid animated graphics, detailed weather maps, and hands-on experiments. This episode (23 minutes) looks at how meteorologists gather and interpret current weather data collected from sources…

  17. Cold-Weather Sports

    MedlinePlus

    ... Surgery? A Week of Healthy Breakfasts Shyness Cold-Weather Sports KidsHealth > For Teens > Cold-Weather Sports Print A A A What's in this ... Equipment Ahh, winter! Shorter days. Frigid temperatures. Foul weather. What better time to be outdoors? Winter sports ...

  18. Hot Weather Tips

    MedlinePlus

    ... FCA - A A + A You are here Home HOT Weather Tips Printer-friendly version We all suffer in hot weather. However, for elderly and disabled people and ... stress and following these tips for dealing with hot weather. Wear cool clothing: See that the person ...

  19. The Ançã limestones, Coimbra, Portugal

    NASA Astrophysics Data System (ADS)

    Quinta-Ferreira, Mário; Gil Catarino, Lídia; Delgado Rodrigues, José

    2016-04-01

    Ançã is located in the Lusitanian Basin (western Meso-Cenozoic sedimentary basin), in the municipality of Cantanhede, close to Coimbra, Portugal. This constitutes the northernmost Dogger (Bajocian) limestone sequence in Portugal. The use of the Ançã limestones is documented since the Roman occupation of the Iberian Peninsula. It was used for the construction of houses, palaces, churches, fine sculptures, carving, paving and for the production of lime. These limestones vary from white and very soft varieties, with very high porosity used for sculpture and carving to white and hard varieties used for masonry and as aggregates and to white to bluish with low porosity and high strength varieties, mainly used for paving. The softer and whiter variety is worldwide known as Ançã Stone (Pedra de Ançã) exhibiting a porosity of 26-29 %. It became famous after being largely used by Coimbra most famous Renaissance sculptors like João de Ruão and Nicolau de Chanterenne. The Pedra de Ançã was used mainly in the region of Coimbra, but also in several other places in Portugal, in Santiago de Compostela, Spain, and Brazil. Some examples of heritage in Coimbra using the Pedra de Ançã are the renaissance portal of the Saint Cross Church, the tombs of the first two Portuguese kings located in this church, the altar of the Saint Cross Church or of the Old Cathedral, or in sculptures at the University of Coimbra. It is quite prone to deteriorate when exposed to atmospheric agents and to soluble salts, mainly due to its high porosity. Deteriorated surfaces needing treatment constitute difficult conservation problems, especially when consolidation and protection treatments are required. The less porous varieties of the Ançã limestones (< 20 % porosity) were mainly used for masonry, paving and production of lime. The royal Palace of Buçaco is a remarkable masonry building constructed at the end of the XIX century with the less porous varieties of the Ançã limestones

  20. Leaching of clay minerals in a limestone environment

    USGS Publications Warehouse

    Carroll, D.; Starkey, H.C.

    1959-01-01

    Water saturated with CO2 at about 25??C was percolated through mixed beds of limestone or marble fragments and montmorillonite, "illite" and kaolinite in polyethylene tubes for six and fortyfive complete runs. The leachates were analysed for SiO2, A12O3 and Fe2O3, but only SiO2 was found. The minerals lost SiO2 in this order: montmorillonite > kaolinite > "illite". The differential removal of SiO2 during the short period of these experiments suggests a mechanism for the accumulation of bauxite deposits associated with limestones. ?? 1959.

  1. Weathering: methods and techniques to measure

    NASA Astrophysics Data System (ADS)

    Lopez-Arce, P.; Zornoza-Indart, A.; Alvarez de Buergo, M.; Fort, R.

    2012-04-01

    Surface recession takes place when weathered material is removed from the rocks. In order to know how fast does weathering and erosion occur, a review of several methods, analyses and destructive and non-destructive techniques to measure weathering of rocks caused by physico-chemical changes that occur in bedrocks due to salt crystallization, freezing-thaw, thermal shock, influence of water, wind, temperature or any type of environmental agent leading to weathering processes and development of soils, in-situ in the field or through experimental works in the laboratory are addressed. From micro-scale to macro-scale, from the surface down to more in depth, several case studies on in-situ monitoring of quantification of decay on soils and rocks from natural landscapes (mountains, cliffs, caves, etc) or from urban environment (foundations or facades of buildings, retaining walls, etc) or laboratory experimental works, such as artificial accelerated ageing tests (a.a.e.e.) or durability tests -in which one or more than one weathering agents are selected to assess the material behaviour in time and in a cyclic way- performed on specimens of these materials are summarised. Discoloration, structural alteration, precipitation of weathering products (mass transfer), and surface recession (mass loss) are all products of weathering processes. Destructive (SEM-EDX, optical microscopy, mercury intrusion porosimetry, drilling resistance measurement, flexural and compression strength) and Non-destructive (spectrophotocolorimetry, 3D optical surface roughness, Schmidt hammer rebound tester, ultrasound velocity propagation, Nuclear Magnetic Resonance NMR, X ray computed micro-tomography or CT-scan, geo-radar differential global positioning systems) techniques and characterization analyses (e.g. water absorption, permeability, open porosity or porosity accessible to water) to assess their morphological, physico-chemical, mechanical and hydric weathering; consolidation products or

  2. Investigating the Variable Durability of Malta's Lower Globigerina Limestone to Soluble-Salt Damage.

    NASA Astrophysics Data System (ADS)

    Zammit, Tano; Cassar, JoAnn

    2014-05-01

    Investigating the Variable Durability of Malta's Lower Globigerina Limestone to Soluble-Salt Damage. Tano Zammit, JoAnn Cassar Department of the Built Heritage, Faculty for the Built Environment. University of Malta. The millenary use of Lower Globigerina Limestone (LGL) as a building stone in the Maltese Islands, and its export to other Mediterranean countries in the past, is confirmation of its validity. Notwithstanding the diminishing economic importance of this once principal resource of the local building industry, the ever growing need for conservation of Malta's rich patrimony of archaeological/historical buildings and structures built of this stone, emphasise the need for on-going research particularly that investigating its variable durability. The research under discussion here forms part of a wider research programme on the characterisation of this locally very important resource. In this investigation the durability of the LGL is considered in terms of two main climatic features, namely a temperate Mediterranean climate involving i) a salt-laden marine environment together with ii) relatively short spans of heavy precipitations alternating with longer periods of virtual drought. It is virtually impossible to all but the quarry owners to identify 'good' from 'bad' quality stone simply through the visual observation, as LGL is a fine-grained, white to yellow, homogenous limestone. On the other hand, it is empirically known that LGL is a moderately weak limestone, characterized by the predominance of the mineral calcite (86 - 99%) and by a high total porosity (up to 40%) of which, over 85%, is microporosity below 5µm. In theory, these physical properties should render such stone-type particularly susceptible to deterioration involving a) mechanisms of capillary salt-laden moisture accumulation and movement together with, b) thermodynamic changes of soluble-salts during dissolution and crystallization cycles. The adopted research methodology investigating

  3. Self-organized geodynamics of karst limestone landscapes and coupled terra rossa/bauxite formation

    NASA Astrophysics Data System (ADS)

    Merino, E.; Wang, Y.; Banerjee, A.

    2012-12-01

    Why do flat limestones overlain by terra rossa or bauxite systematically adopt so-called karst geomorphology, which consists of sets of roughly regularly spaced wormholes, or funnels, or sinkholes, or tower karst? The idea that the funnels and sinkholes are located at the intersections of preexisting sets of subvertical fractures is untenable. New field and petrographic evidence (Merino & Banerjee, J. Geology, 2008) revealed that, rather than 'residual' or 'detrital' (the only options that have been on the table for decades), the terra rossa/bauxite clays and Al- and Fe-oxyhydroxides grow authigenically at the base of the terra rossa, replacing the underlying limestone at a generally downward-moving reaction front several centimeters thick. The clay-for-limestone replacement, which preserves solid volume (because it takes place by clay-growth-driven pressure solution of calcite), releases H+ ions. These dissolve more calcite, generating considerable leached porosity in a narrow zone that travels with the replacement front. We proposed (Merino & Banerjee, J. Geology, 2008) that the moving leached-porosity maximum created at the front could trigger the reactive-infiltration instability (Chadam et al, IMA J. Appl. Math., 1986), causing the replacement-and-leaching reaction front to become regularly fingered, with the fingers jumping in scale to funnels, these to sinks, and these, when deep enough and merged together laterally, to tower karst. This new geodynamics would account both for the world-wide association of terra rossa and bauxite with karst limestones, and for the stunning, self-organized geomorphology of karst itself. We are testing these ideas through linear stability analysis of a simplified reaction-transport system of equations and through numerical solution of the full non-linear system of reaction-transport equations applicable, including aqueous speciation. Preliminary calculations (Banerjee & Merino, J. Geology, 2011) suggest that the replacement

  4. Weatherization and Intergovernmental Program - Weatherization Assistance Program

    SciTech Connect

    2010-06-01

    The U.S. Department of Energy’s (DOE) Weatherization Assistance Program reduces energy costs for low-income households by increasing the energy efficiency of their homes, while ensuring their health and safety.

  5. Physical and microstructural aspects of sulfate attack on ordinary and limestone blended Portland cements

    SciTech Connect

    Schmidt, Thomas; Lothenbach, Barbara; Romer, Michael; Neuenschwander, Juerg; Scrivener, Karen

    2009-12-15

    The consequences of external sulfate attack were investigated by traditional test methods, i.e. length and mass change, as well as by a newly developed, surface sensitive ultrasonic method, using Leaky Rayleigh waves (1 MHz). The macroscopic changes are discussed and compared with thermodynamic calculations and microstructural findings (SEM/EDS). The results show that the main impact of limestone additions on resistance to sulfate degradation are physical - i.e. addition of a few percent in Portland cement reduces the porosity and increases the resistance of Portland cement systems to sulfate; but higher addition of 25% increase porosity and lower resistance to sulfate. The kinetics of degradation were dramatically affected by the solution concentration (4 or 44 g Na{sub 2}SO{sub 4}/l) and the higher concentration also resulted in the formation of gypsum, which did not occur at the low concentration. However the pattern of cracking was similar in both cases and it appears that gypsum precipitates opportunistically in pre-formed cracks so it is not considered as making a significant contribution to the degradation. At 8 deg. C limited formation of thaumasite occurred in the surface region of the samples made from cement with limestone additions. This thaumasite formation led to loss of cohesion of the paste and loss of material from the surface of the samples. However thaumasite formation was always preceded by expansion and cracking of the samples due to ettringite formation and given the very slow kinetics of thaumasite formation it was probably facilitated by the opening up of the structure due to ettringite induced cracking. The expansion of the samples showed a steady stage, followed by a rapidly accelerating stage, with destruction of the samples. The onset of the rapidly accelerating stage occurred when the thickness of the cracked surface layer reached about 1-1.5 mm-10-15% of the total specimen thickness (10 mm).

  6. View of the main entrance with basrelief limestone panel designed ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of the main entrance with bas-relief limestone panel designed by C. Paul Jennwein upon which is inscribed "Lege Atque Ordine Omnia Fiunt" (translated as by law and order all is accomplished) - United States Department of Justice, Constitution Avenue between Ninth & Tenth Streets, Northwest, Washington, District of Columbia, DC

  7. Detail view to show one of the limestone relief panels ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail view to show one of the limestone relief panels depicting one of the agencies of the Commerce Department, here the Lighthouse Service - United States Department of Commerce, Bounded by Fourteenth, Fifteenth, and E streets and Constitution Avenue, Washington, District of Columbia, DC

  8. The Solnhofen Limestone: A stony heritage of many uses

    NASA Astrophysics Data System (ADS)

    Kölbl-Ebert, Martina; Kramar, Sabina; Cooper, Barry J.

    2016-04-01

    High above the valley of the River Altmühl (Bavaria, Germany), between Solnhofen to the west and Kelheim to the east, numerous quarries give access to thinly plated limestone from the Upper Jurassic, some 150 million years before the present. The main quarry areas lie around the town of Eichstätt and between the villages of Solnhofen, Langenaltheim and Mörnsheim. Here limestone slabs have been quarried for several hundred years, some even in Roman times. Solnhofen Limestone is famous worldwide; not only because it is a beautiful building stone of high quality, but also because of the exceptionally well-preserved fossils it contains -among them the early bird Archaeopteryx. The quarry industry between Solnhofen and Eichstätt has shaped a cultural landscape, with old and new quarries sunk into the plain and numerous spoil heaps rising above it, for the rock is not all economically useful. But many of the spoil heaps and the old quarries are environmentally protected as they provide a habitat for some rare plants and animals. It is not necessary to cut the Solnhofen Limestone with a saw: it is split by hand into thin and even slabs or sheets which are used for flagstones and wall covers, which since centuries are sold world-wide. Locally it also serves as roof tiles for traditional houses. Thick slabs of especially fine quality may be found near Solnhofen and Mörnsheim and are used for lithography printing.

  9. Fracture Decoupling of Small Chemical Explosions in Granite and Limestone

    NASA Astrophysics Data System (ADS)

    Stroujkova, A. F.; Bonner, J. L.; Reinke, R.; Lenox, E. A.

    2012-12-01

    Reduction of the seismic amplitudes produced by underground explosions due to dissipation in a low-coupling medium poses a significant challenge for nuclear test monitoring. We examined the data from two experiments, which involved conducting explosions in the damage zone created by previous explosions ("repeat shots"). The first experiment was conducted in central New Hampshire in a fluid saturated granodiorite. The experiment involved detonating two 46 kg explosions: one in virgin rock and the other in the fractured rock zone produced by a larger (232 kg) explosion. The second experiment took place near Albuquerque, NM, in dry limestone. In this scenario the second explosion was conducted in the cavity created by the first explosion. Both limestone explosions had yields of 90.5 kg. The reduction of the seismic amplitudes was observed for both repeat shots: in granodiorite the amplitudes were reduced by a factor of 2-3, in limestone by a factor of 3-4 compared to the shots in the undamaged rocks. For the granodiorite repeat shot the decoupling ratios were frequency dependent with stronger amplitude reduction at higher frequencies. In addition, the virgin rock shot produced higher corner frequency and overshoot parameter than the repeat shot. For the limestone shot the decoupling ratios were nearly flat at all frequencies with similar corner frequencies. This observation suggests different mechanisms of energy dissipation for the two experiments.

  10. Curved limestone wall at east end of rail yard. Note ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Curved limestone wall at east end of rail yard. Note cut off valves at base of stump in right foreground, and utility tunnel in middle distance, superindent's house at right, looking NW. - Grand Canyon Village Utilities, Grand Canyon National Park, Grand Canyon Village, Coconino County, AZ

  11. The influence of additives on rheological properties of limestone slurry

    NASA Astrophysics Data System (ADS)

    Jaworska, B.; Bartosik, A.

    2014-08-01

    Limestone slurry appears in the lime production process as the result of rinsing the processed material. It consists of particles with diameter smaller than 2 mm and the water that is a carrier of solid fraction. Slurry is directed to the settling tank, where the solid phase sediments and the excess water through the transfer system is recovered for re-circulation. Collected at the bottom of the tank sludge is deposited in a landfill located on the premises. Rheological properties of limestone slurry hinder its further free transport in the pipeline due to generated flow resistance. To improve this state of affairs, chemical treatment of drilling fluid, could be applied, of which the main task is to give the slurry properties suitable for the conditions encountered in hydrotransport. This treatment consists of applying chemical additives to slurry in sufficient quantity. Such additives are called as deflocculants or thinners or dispersants, and are chemical compounds which added to aqueous solution are intended to push away suspended particles from each other. The paper presents the results of research allowing reduction of shear stress in limestone slurry. Results demonstrate rheological properties of limestone slurry with and without the addition of modified substances which causes decrease of slurry viscosity, and as a consequence slurry shear stress for adopted shear rate. Achieving the desired effects increases the degree of dispersion of the solid phase suspended in the carrier liquid and improving its ability to smooth flow with decreased friction.

  12. Soil respiration patterns and controls in limestone cedar glades

    USGS Publications Warehouse

    Cartwright, Jennifer M.; Hui, Dafeng

    2015-01-01

    Soil depth, SOM, and vegetation cover were important drivers of Rs in limestone cedar glades. Seasonal Rs patterns reflected those for mesic temperate grasslands more than for semi-arid ecosystems, in that Rs primarily tracked temperature for most of the year.

  13. Geology of the Limestone Hills, Broadwater County, Montana

    USGS Publications Warehouse

    Ruppel, Edward Thompson

    1950-01-01

    The Limestone Hills, a natural topographic unit having an area of about 16 square miles, are situated a few miles west and southwest of Townsend, Broadwater County, Montana. They are composed of pre-Cambrian, Paleozoic, and Mesozoic sedimentary rocks i

  14. 14. A VIEW SOUTHEAST OF A PORTION OF THE LIMESTONE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. A VIEW SOUTHEAST OF A PORTION OF THE LIMESTONE ABUTMENT, THE UNDERSIDE OF THE INCLINED END POST AND A PLATE USED TO ATTACH THE STRUCTURE TO THE ABUTMENT. - Wells County Bridge No. 74, Spanning Rock Creek Ditch at County Road 400, Bluffton, Wells County, IN

  15. 44. Tube conveyors carry ore, coke and limestone to blast ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    44. Tube conveyors carry ore, coke and limestone to blast furnaces "B" and "C". Ore bridges to left, passenger elevator penthouse immediately to left of conveyor; gas stack and furnace "A" to right. Looking north - Rouge Steel Company, 3001 Miller Road, Dearborn, MI

  16. Morphodynamics of Travertine Dam/Waterfall Growth due to the Interaction of Biological Activity, Water Flow and Limestone Emplacement

    NASA Astrophysics Data System (ADS)

    Izumi, N.; Parker, G.

    2012-12-01

    Plitvice Lakes in Croatia are characterized by a step-like train of lakes and waterfalls. The waterfalls are located at the crests of naturally-emplaced dams. The top of each dam grows upward at the rate of a few millimeters per year. It is thought that the upward growth of these dams is caused by the interaction of water flow and biological activity, resulting in the precipitation of dissolved limestone. Dam evolution is initiated by the growth of mosses that favor swift, shallow water. Bacteria that inhabit the roots of the moss excrete solid limestone (travertine) from the water. The limestone fossilizes the moss, and then more moss grows on top of the travertine deposit. In this way, the natural dam can grow over to 10 m high, impounding the water behind it to form a lake. We propose a simple model to explain the formation of natural limestone dams by the interaction between water flow and biologically-mediated travertine deposition. We assume for simplicity that light is the only factor determining the growth of moss, which is then colonized by travertine-emplacing bacteria. We also assume that the water is saturated with dissolved limestone, so that the process is not limited by limestone availability. Photosynthesis, and thus the growth rate of moss are crudely approximated as decreasing linearly with depth. We employ the shallow water equations to describe water flow over the dam. In order to obtain a profile of permanent form for a dam migrating upward and downstream at constant speed, we solve the problem in a moving coordinate system. When water flows over the dam, it is accelerated in the streamwise direction, and the water surface forms a backwater curve. The flow regime changes from Froude-subcritical to Froude-supercritical at a point slightly downstream of the crest of the dam. Farther downstream, the flow attains a threshold velocity beyond which moss is detached. This threshold point defines the downstream end of the active part of the dam. The

  17. Porosity change after gypsum crust formation on macro-porous limestones

    NASA Astrophysics Data System (ADS)

    Dewanckele, Jan; Cnudde, Veerle; de Kock, Tim; Boone, Marijn; Boone, Matthieu; van Hoorebeke, Luc; Jacobs, Patric

    2010-05-01

    filter, etc. were applied for the reconstruction. Total porosity, open and closed porosity and radial porosity were calculated for each sample by using the in-house developed software program Morpho+. The analysis of the various scans revealed that the Euville limestone developed a distinct gypsum crust, behind which a secondary porous layer of 100 μm thickness had developed. Inside the sample the porosity decreased by infilling of the large pore spaces with gypsum. However, after 6 days exposure the total porosity of the sample increased from 5.70% to 8.45%. In this case, the formation of secondary porosity behind the newly formed exterior gypsum layer prevailed upon the crystallizing of gypsum inside the pores located in the sample's interior. Also, the firstly formed gypsum crystals prevented the further interaction of the sulphuric acid with the stone material. After 21 days, the total porosity of the sample still reached 8.45%. The results of the radial porosity measurements were also the same after 6 and 21 days, indicating that the secondary porosity and the filling of pores inside the samples were stabilized. On the other hand, the gypsum crust on the Savonnières limestone was less visible. No secondary formed porous layer was measured and the total porosity decreased from 12.10% to 10.94% after 6 days and further to 10.31% at the end of the test. The decrease of porosity was still measurable at a depth of 500 μm inside the sample. The combination of micro-CT, image analysis and induced weathering tests are a promising combination of tools and techniques that allow for a better understanding of gypsum crust formation and pore structure change just behind the crust and deeper inside the rock sample.

  18. THOR contribution to space weather science

    NASA Astrophysics Data System (ADS)

    Vaivads, Andris; Opgenoorth, Hermann; Retinò, Alessandro; Khotyaintsev, Yuri; Soucek, Jan; Valentini, Francesco; Escoubet, Philippe

    2016-04-01

    Turbulence Heating ObserveR - THOR is a mission proposal to study energy dissipation and particle acceleration in turbulent space plasma. THOR will focus on turbulent plasma in pristine solar wind, bow shock and magnetosheath. The orbit of THOR is tuned to spend long times in those regions allowing THOR to obtain high resolution data sets that can be used also for space weather science. In addition, THOR is designed with enough propellant to reach L1 in the second phase of the mission if necessary. Here we will discuss the space weather science questions that can be addressed and significantly advanced using THOR. Link to THOR: http://thor.irfu.se.

  19. Space Weathering of Rocks

    NASA Technical Reports Server (NTRS)

    Noble, Sarah

    2011-01-01

    Space weathering discussions have generally centered around soils but exposed rocks will also incur the effects of weathering. On the Moon, rocks make up only a very small percentage of the exposed surface and areas where rocks are exposed, like central peaks, are often among the least space weathered regions we find in remote sensing data. However, our studies of weathered Ap 17 rocks 76015 and 76237 show that significant amounts of weathering products can build up on rock surfaces. Because rocks have much longer surface lifetimes than an individual soil grain, and thus record a longer history of exposure, we can study these products to gain a deeper perspective on the weathering process and better assess the relative impo!1ance of various weathering components on the Moon. In contrast to the lunar case, on small asteroids, like Itokowa, rocks make up a large fraction of the exposed surface. Results from the Hayabusa spacecraft at Itokowa suggest that while the low gravity does not allow for the development of a mature regolith, weathering patinas can and do develop on rock surfaces, in fact, the rocky surfaces were seen to be darker and appear spectrally more weathered than regions with finer materials. To explore how weathering of asteroidal rocks may differ from lunar, a set of ordinary chondrite meteorites (H, L, and LL) which have been subjected to artificial space weathering by nanopulse laser were examined by TEM. NpFe(sup 0) bearing glasses were ubiquitous in both the naturally-weathered lunar and the artificially-weathered meteorite samples.

  20. Limestone dissolution in modeling of slurry scrubbing for flue-gas desulfurization

    SciTech Connect

    Gage, C.L.

    1989-01-01

    Batch limestone dissolution experiments were carried out in a pH stat apparatus at 550C with CO{sub 2} sparging and dissolved sulfite. Particle size distribution, utilization, sulfite in solution, limestone type, and the approach to calcite equilibrium were all found to contribute to the limestone reactivity. In the absence of sulfite limestone dissolution was controlled solely by mass transfer. A surface rate correlation was developed which accounted for observed inhibition by an inverse dependence on calcium sulfite concentration at the limestone surface. A computer code which accounted for mass transfer with surface kinetics was tested against experimental observations of four limestone types. Changes in pH and the concentrations of calcium, carbonate, sulfite, sulfate, and adipic acid were accurately modeled. An overall slurry scrubber model was expanded to predict limestone reactivity from particle size and solution effects. This model predicts scrubber performance and hold tank compositions from the chemistry of the limestone slurry process. Additional subroutines were written to predict particle size distributions from sieve data using the log gamma density function. The expanded model was tested against a limestone type and grind study which investigated utilizations of four limestone types at ten different grinds. The expanded Slurry Scrubber Model was able to predict both SO{sub 2} removal and hold tank compositions of the limestone study. The effects of limestone type were handled through changes in the surface rate parameter. Within a given type the effects of grind and utilization were well modeled.

  1. Quarry Quest. A Field Trip Guide to the Indiana Limestone District, Monroe and Lawrence Counties, Indiana.

    ERIC Educational Resources Information Center

    Shewmaker, Sherman N.

    This guide provides information for planning a field trip to the Indiana Limestone District. This district, located in Monroe and Lawrence Counties, Indiana, is responsible for material that has dominated the building-limestone market in the United States for nearly a century. A few of the many well-known buildings using Indiana limestone are the…

  2. NASA Connect: 'Plane Weather'

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Excerpt from the NASA Connect show 'Plane Weather' This clip explains what high and low pressure weather systems are, and how these affect weather patterns. Weather affects our daily lives. The elements of weather: rain, wind, fog, ice and snow affect the operation and flight of an airplane. In this program, NASA and FAA researchers will introduce students to math, science, and weather; demonstrate how these elements influence flight; and show how NASA and FAA research is used to limit the effects of these elements on flight. Students will examine: the tools, techniques, and technologies used by engineers and scientists to detect these and other climatological factors affecting aircraft in flight. The lesson and classroom experiment will involve students in the scientific process and emphasizing problem solving, measurement, and reasoning skills.

  3. Tales of future weather

    NASA Astrophysics Data System (ADS)

    Hazeleger, W.; van den Hurk, B. J. J. M.; Min, E.; van Oldenborgh, G. J.; Petersen, A. C.; Stainforth, D. A.; Vasileiadou, E.; Smith, L. A.

    2015-02-01

    Society is vulnerable to extreme weather events and, by extension, to human impacts on future events. As climate changes weather patterns will change. The search is on for more effective methodologies to aid decision-makers both in mitigation to avoid climate change and in adaptation to changes. The traditional approach uses ensembles of climate model simulations, statistical bias correction, downscaling to the spatial and temporal scales relevant to decision-makers, and then translation into quantities of interest. The veracity of this approach cannot be tested, and it faces in-principle challenges. Alternatively, numerical weather prediction models in a hypothetical climate setting can provide tailored narratives for high-resolution simulations of high-impact weather in a future climate. This 'tales of future weather' approach will aid in the interpretation of lower-resolution simulations. Arguably, it potentially provides complementary, more realistic and more physically consistent pictures of what future weather might look like.

  4. Weather and climate

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Recommendations for using space observations of weather and climate to aid in solving earth based problems are given. Special attention was given to: (1) extending useful forecasting capability of space systems, (2) reducing social, economic, and human losses caused by weather, (3) development of space system capability to manage and control air pollutant concentrations, and (4) establish mechanisms for the national examination of deliberate and inadvertent means for modifying weather and climate.

  5. Weatherization Innovation Pilot Program (WIPP): Technical Assistance Summary

    SciTech Connect

    Hollander, A.

    2014-09-01

    The U.S. Department of Energy (DOE) Energy Efficiency and Renewable Energy (EERE) Weatherization and Intergovernmental Programs Office (WIPO) launched the Weatherization Innovation Pilot Program (WIPP) to accelerate innovations in whole-house weatherization and advance DOE's goal of increasing the energy efficiency and health and safety of low-income residences without the utilization of additional taxpayer funding. Sixteen WIPP grantees were awarded a total of $30 million in Weatherization Assistance Program (WAP) funds in September 2010. These projects focused on: including nontraditional partners in weatherization service delivery; leveraging significant non-federal funding; and improving the effectiveness of low-income weatherization through the use of new materials, technologies, behavior-change models, and processes.

  6. Weather assessment and forecasting

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Data management program activities centered around the analyses of selected far-term Office of Applications (OA) objectives, with the intent of determining if significant data-related problems would be encountered and if so what alternative solutions would be possible. Three far-term (1985 and beyond) OA objectives selected for analyses as having potential significant data problems were large-scale weather forecasting, local weather and severe storms forecasting, and global marine weather forecasting. An overview of general weather forecasting activities and their implications upon the ground based data system is provided. Selected topics were specifically oriented to the use of satellites.

  7. Cockpit weather information needs

    NASA Technical Reports Server (NTRS)

    Scanlon, Charles H.

    1992-01-01

    The primary objective is to develop an advanced pilot weather interface for the flight deck and to measure its utilization and effectiveness in pilot reroute decision processes, weather situation awareness, and weather monitoring. Identical graphical weather displays for the dispatcher, air traffic control (ATC), and pilot crew should also enhance the dialogue capabilities for reroute decisions. By utilizing a broadcast data link for surface observations, forecasts, radar summaries, lightning strikes, and weather alerts, onboard weather computing facilities construct graphical displays, historical weather displays, color textual displays, and other tools to assist the pilot crew. Since the weather data is continually being received and stored by the airborne system, the pilot crew has instantaneous access to the latest information. This information is color coded to distinguish degrees of category for surface observations, ceiling and visibilities, and ground radar summaries. Automatic weather monitoring and pilot crew alerting is accomplished by the airborne computing facilities. When a new weather information is received, the displays are instantaneously changed to reflect the new information. Also, when a new surface or special observation for the intended destination is received, the pilot crew is informed so that information can be studied at the pilot's discretion. The pilot crew is also immediately alerted when a severe weather notice, AIRMET or SIGMET, is received. The cockpit weather display shares a multicolor eight inch cathode ray tube and overlaid touch panel with a pilot crew data link interface. Touch sensitive buttons and areas are used for pilot selection of graphical and data link displays. Time critical ATC messages are presented in a small window that overlays other displays so that immediate pilot alerting and action can be taken. Predeparture and reroute clearances are displayed on the graphical weather system so pilot review of weather along

  8. Pilot Weather Advisor System

    NASA Technical Reports Server (NTRS)

    Lindamood, Glenn; Martzaklis, Konstantinos Gus; Hoffler, Keith; Hill, Damon; Mehrotra, Sudhir C.; White, E. Richard; Fisher, Bruce D.; Crabill, Norman L.; Tucholski, Allen D.

    2006-01-01

    The Pilot Weather Advisor (PWA) system is an automated satellite radio-broadcasting system that provides nearly real-time weather data to pilots of aircraft in flight anywhere in the continental United States. The system was designed to enhance safety in two distinct ways: First, the automated receipt of information would relieve the pilot of the time-consuming and distracting task of obtaining weather information via voice communication with ground stations. Second, the presentation of the information would be centered around a map format, thereby making the spatial and temporal relationships in the surrounding weather situation much easier to understand

  9. Characterization of limestone reacted with acid-mine drainage in a pulsed limestone bed treatment system at the Friendship Hill National Historical Site, Pennsylvania, USA

    USGS Publications Warehouse

    Hammarstrom, J.M.; Sibrell, P.L.; Belkin, H.E.

    2003-01-01

    Armoring of limestone is a common cause of failure in limestone-based acid-mine drainage (AMD) treatment systems. Limestone is the least expensive material available for acid neutralization, but is not typically recommended for highly acidic, Fe-rich waters due to armoring with Fe(III) oxyhydroxide coatings. A new AMD treatment technology that uses CO2 in a pulsed limestone bed reactor minimizes armor formation and enhances limestone reaction with AMD. Limestone was characterized before and after treatment with constant flow and with the new pulsed limestone bed process using AMD from an inactive coal mine in Pennsylvania (pH = 2.9, Fe = 150 mg/l, acidity = 1000 mg/l CaCO3). In constant flow experiments, limestone is completely armored with reddish-colored ochre within 48 h of contact in a fluidized bed reactor. Effluent pH initially increased from the inflow pH of 2.9 to over 7, but then decreased to 6 during operation. Limestone removed from a pulsed bed pilot plant is a mixture of unarmored, rounded and etched limestone grains and partially armored limestone and refractory mineral grains (dolomite, pyrite). The ???30% of the residual grains in the pulsed flow reactor that are armored have thicker (50- to 100-??m), more aluminous coatings and lack the gypsum rind that develops in the constant flow experiment. Aluminium-rich zones developed in the interior parts of armor rims in both the constant flow and pulsed limestone bed experiments in response to pH changes at the solid/solution interface. ?? 2003 Elsevier Ltd. All rights reserved.

  10. CCMC/Space Weather Research Center: Overview and Future Space Weather Needs

    NASA Astrophysics Data System (ADS)

    Zheng, Y.; Pulkkinen, A. A.; Kuznetsova, M. M.; Maddox, M. M.

    2015-12-01

    Space Weather Research Center (SWRC), part of the Community Coordinated Modeling Center (CCMC), was established in 2010 to address emerging space weather needs of NASA robotic missions. By leveraging CCMC's modeling capabilities and through collaborations with different NASA centers, government agencies, educational institutions and multiple entities worldwide, SWRC provides research-based space weather forecasting, monitoring and anomaly support to NASA users. SWRC analyst team has also helped to identify limitations of current models and thus accelerate R2O-O2R process. In addition, the establishment of SWRC has added a new dimension to CCMC's education program. In this presentation, an overview of SWRC activities will be given. Future research and modeling needs will be discussed from the perspective of a space weather analyst.

  11. Performance of portland limestone cements: Cements designed to be more sustainable that include up to 15% limestone addition

    NASA Astrophysics Data System (ADS)

    Barrett, Timothy J.

    In 2009, ASTM and AASHTO permitted the use of up to 5% interground limestone in ordinary portland cement (OPC) as a part of a change to ASTM C150/AASHTO M85. When this work was initiated a new proposal was being discussed that would enable up to 15% interground limestone cement to be considered in ASTM C595/AASHTO M234. This work served to provide rapid feedback to the state department of transportation and concrete industry for use in discussions regarding these specifications. Since the time this work was initiated, ASTM C595/AASHTO M234 was passed (2012c) and PLCs are now able to be specified, however they are still not widely used. The proposal for increasing the volume of limestone that would be permitted to be interground in cement is designed to enable more sustainable construction, which may significantly reduce the CO2 that is embodied in the built infrastructure while also extending the life of cement quarries. Research regarding the performance of cements with interground limestone has been conducted by the cement industry since these cements became widely used in Europe over three decades ago, however this work focuses on North American Portland Limestone Cements (PLCs) which are specifically designed to achieve similar performance as the OPCs they replace.This thesis presents a two-phase study in which the potential for application of cements containing limestone was assessed. The first phase of this study utilized a fundamental approach to determine whether cement with up to 15% of interground or blended limestone can be used as a direct substitute to ordinary portland cement. The second phase of the study assessed the concern of early age shrinkage and cracking potential when using PLCs, as these cements are typically ground finer than their OPC counterparts. For the first phase of the study, three commercially produced PLCs were obtained and compared to three commercially produced OPCs made from the same clinker. An additional cement was tested

  12. Weather and emotional state

    NASA Astrophysics Data System (ADS)

    Spasova, Z.

    2010-09-01

    Introduction Given the proven effects of weather on the human organism, an attempt to examine its effects on a psychic and emotional level has been made. Emotions affect the bio-tonus, working ability and concentration, hence their significance in various domains of economic life, such as health care, education, transportation, tourism, etc. Data and methods The research has been made in Sofia City within a period of 8 months, using 5 psychological methods (Eysenck Personality Questionnaire (EPQ), State-Trait Anxiety Inventory (STAI), Test for Self-assessment of the emotional state (developed by Wessman and Ricks), Test for evaluation of moods and Test "Self-confidence - Activity - Mood" (developed by the specialists from the Military Academy in Saint Petersburg). The Fiodorov-Chubukov's complex-climatic method was used to characterize meteorological conditions because of the purpose to include in the analysis a maximal number of meteorological elements. 16 weather types are defined in dependence of the meteorological elements values according to this method. Abrupt weather changes from one day to another, defined by the same method, were considered as well. Results and discussions The results obtained by t-test show that the different categories of weather lead to changes in the emotional status, which indicates a character either positive or negative for the organism. The abrupt weather changes, according to expectations, have negative effect on human emotions but only when a transition to the cloudy weather or weather type, classified as "unfavourable" has been realized. The relationship between weather and human emotions is rather complicated since it depends on individual characteristics of people. One of these individual psychological characteristics, marked by the dimension "neuroticism", has a strong effect on emotional reactions in different weather conditions. Emotionally stable individuals are more "protected" to the weather influence on their emotions

  13. Preservation of York Minster historic limestone by hydrophobic surface coatings

    PubMed Central

    Walker, Rachel A.; Wilson, Karen; Lee, Adam F.; Woodford, Julia; Grassian, Vicki H.; Baltrusaitis, Jonas; Rubasinghege, Gayan; Cibin, Giannantonio; Dent, Andrew

    2012-01-01

    Magnesian limestone is a key construction component of many historic buildings that is under constant attack from environmental pollutants notably by oxides of sulfur via acid rain, particulate matter sulfate and gaseous SO2 emissions. Hydrophobic surface coatings offer a potential route to protect existing stonework in cultural heritage sites, however, many available coatings act by blocking the stone microstructure, preventing it from ‘breathing' and promoting mould growth and salt efflorescence. Here we report on a conformal surface modification method using self-assembled monolayers of naturally sourced free fatty acids combined with sub-monolayer fluorinated alkyl silanes to generate hydrophobic (HP) and super hydrophobic (SHP) coatings on calcite. We demonstrate the efficacy of these HP and SHP surface coatings for increasing limestone resistance to sulfation, and thus retarding gypsum formation under SO2/H2O and model acid rain environments. SHP treatment of 19th century stone from York Minster suppresses sulfuric acid permeation. PMID:23198088

  14. Background radiation measurements at 2200 ft depth in limestone mine.

    NASA Astrophysics Data System (ADS)

    Olling Back, Henning; Vogelaar, R. Bruce; Johnson, D. Nathan

    2003-10-01

    An active limestone mine in southwestern Virginia is being investigated as a possible site for detectors requiring a low muon flux. The current depth of the mine is 2200 feet. However, the mining operations continue to follow a vain of pure limestone at a 30-degree downward plane under a rising escarpment, and so greater depths can be achieved relatively quickly. With over 50 miles of drifts, many 100 ft high and 40 ft wide, and drive in access, this is a potential venue for future low background detectors. We will be reporting initial measurements of the muon flux as a function of zenith angle, as well as the ambient gamma radiation from the surrounding rock.

  15. Preservation of York Minster historic limestone by hydrophobic surface coatings

    NASA Astrophysics Data System (ADS)

    Walker, Rachel A.; Wilson, Karen; Lee, Adam F.; Woodford, Julia; Grassian, Vicki H.; Baltrusaitis, Jonas; Rubasinghege, Gayan; Cibin, Giannantonio; Dent, Andrew

    2012-11-01

    Magnesian limestone is a key construction component of many historic buildings that is under constant attack from environmental pollutants notably by oxides of sulfur via acid rain, particulate matter sulfate and gaseous SO2 emissions. Hydrophobic surface coatings offer a potential route to protect existing stonework in cultural heritage sites, however, many available coatings act by blocking the stone microstructure, preventing it from `breathing' and promoting mould growth and salt efflorescence. Here we report on a conformal surface modification method using self-assembled monolayers of naturally sourced free fatty acids combined with sub-monolayer fluorinated alkyl silanes to generate hydrophobic (HP) and super hydrophobic (SHP) coatings on calcite. We demonstrate the efficacy of these HP and SHP surface coatings for increasing limestone resistance to sulfation, and thus retarding gypsum formation under SO2/H2O and model acid rain environments. SHP treatment of 19th century stone from York Minster suppresses sulfuric acid permeation.

  16. Cement substitution by a combination of metakaolin and limestone

    SciTech Connect

    Antoni, M.; Rossen, J.; Martirena, F.; Scrivener, K.

    2012-12-15

    This study investigates the coupled substitution of metakaolin and limestone in Portland cement (PC). The mechanical properties were studied in mortars and the microstructural development in pastes by X-ray diffraction, thermogravimetry analysis, mercury intrusion porosimetry and isothermal calorimetry. We show that 45% of substitution by 30% of metakaolin and 15% of limestone gives better mechanical properties at 7 and 28 days than the 100% PC reference. Our results show that calcium carbonate reacts with alumina from the metakaolin, forming supplementary AFm phases and stabilizing ettringite. Using simple mass balance calculations derived from thermogravimetry results, we also present the thermodynamic simulation for the system, which agrees fairly well with the experimental observations. It is shown that gypsum addition should be carefully balanced when using calcined clays because it considerably influences the early age strength by controlling the very rapid reaction of aluminates.

  17. Future accelerators (?)

    SciTech Connect

    John Womersley

    2003-08-21

    I describe the future accelerator facilities that are currently foreseen for electroweak scale physics, neutrino physics, and nuclear structure. I will explore the physics justification for these machines, and suggest how the case for future accelerators can be made.

  18. Time-Dependent Rock Failure in a Heterogeneous Limestone

    NASA Astrophysics Data System (ADS)

    Roth, K.; Kemeny, J.

    2015-12-01

    Time-dependent rock failure is an important aspect in the analysis of long-term rock stability for slopes, dam and bridge foundations, and underground storage facilities. An on-going project at the University of Arizona is using Kartchner Caverns in Benson, Arizona as a natural analog to study such failure by reconstructing the process of natural cave breakdown with subcritical crack growth modeling. Breakdown is thought to occur along joints through the time-dependent failure of rock bridges: sections of intact rock separating discontinuities in a rock mass. The Escabrosa limestone composing the caverns ranges from a more homogenous, even-grained texture to a more heterogeneous texture consisting of coarse-grained veins and solution cavities set in a fine-grained matrix. To determine if the veined regions are more susceptible to fracturing and act as the nuclei of rock bridge failure, fracture toughness tests were conducted for both textures. The subcritical crack growth parameters were calculated using the constant stress-rate method. Results indicate that the more heterogeneous limestone has a higher fracture strength, fracture toughness, and subcritical crack growth index n than the more homogeneous limestone. This is in agreement with previous studies which found that a more complex and heterogeneous microstructure produces a larger microcrack process zone, leading to higher fracture energies and lower susceptibility to subcritical crack growth. Thus, despite their solution cavities, the calcite veins do not localize failure or act as planes of weakness; instead, rock bridges fail through the more homogeneous limestone matrix.

  19. Dolomitization of Quaternary reef limestones, Aitutaki, Cook Islands

    USGS Publications Warehouse

    Hein, J.R.; Gray, S.C.; Richmond, B.M.; White, L.D.

    1992-01-01

    The primary reef framework is considered to have been deposited during several highstands of sea level. Following partial to local recrystallization of the limestone, a signle episode of dolomitization occurred. Both tidal and thermal pumping drove large quantities of seawater through the porous rocks and perhaps maintained a wide mixing zone. However, the isotopic, geochemical and petrographic data do not clearly indicate the extent of seawater mixing. -from Authors

  20. Full-scale results for TAM limestone injection

    SciTech Connect

    Baer, S.

    1996-12-31

    Information is outlined on the use of thermally active marble (TAM) sorbents in boilers. Data are presented on: the comparison of TAM to limestone; NOVACON process development history; CFB test history; CFB pilot scale test; full-scale CFB trial; August, 1996 CFB demonstration; Foster Wheeler Mount Carmel sorbent feed rate comparison and Ca:S comparison; unburned carbon is ash; and advantages and savings in CFB boilers.

  1. Modified dry limestone process for control of sulfur dioxide emissions

    DOEpatents

    Shale, Correll C.; Cross, William G.

    1976-08-24

    A method and apparatus for removing sulfur oxides from flue gas comprise cooling and conditioning the hot flue gas to increase the degree of water vapor saturation prior to passage through a bed of substantially dry carbonate chips or lumps, e.g., crushed limestone. The reaction products form as a thick layer of sulfites and sulfates on the surface of the chips which is easily removed by agitation to restore the reactive surface of the chips.

  2. Weathering Database Technology

    ERIC Educational Resources Information Center

    Snyder, Robert

    2005-01-01

    Collecting weather data is a traditional part of a meteorology unit at the middle level. However, making connections between the data and weather conditions can be a challenge. One way to make these connections clearer is to enter the data into a database. This allows students to quickly compare different fields of data and recognize which…

  3. Designing a Weather Station

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2012-01-01

    The collection and analysis of weather data is crucial to the location of alternate energy systems like solar and wind. This article presents a design challenge that gives students a chance to design a weather station to collect data in advance of a large wind turbine installation. Data analysis is a crucial part of any science or engineering…

  4. KSC Weather and Research

    NASA Technical Reports Server (NTRS)

    Maier, Launa; Huddleston, Lisa; Smith, Kristin

    2016-01-01

    This briefing outlines the history of Kennedy Space Center (KSC) Weather organization, past research sponsored or performed, current organization, responsibilities, and activities, the evolution of weather support, future technologies, and an update on the status of the buoys located offshore of Cape Canaveral Air Force Station and KSC.

  5. Weather Fundamentals: Clouds. [Videotape].

    ERIC Educational Resources Information Center

    1998

    The videos in this educational series, for grades 4-7, help students understand the science behind weather phenomena through dramatic live-action footage, vivid animated graphics, detailed weather maps, and hands-on experiments. This episode (23 minutes) discusses how clouds form, the different types of clouds, and the important role they play in…

  6. Home Weatherization Visit

    ScienceCinema

    Chu, Steven

    2016-07-12

    Secretary Steven Chu visits a home that is in the process of being weatherized in Columbus, OH, along with Ohio Governor Ted Strickland and Columbus Mayor Michael Coleman. They discuss the benefits of weatherization and how funding from the recovery act is having a direct impact in communities across America.

  7. On Observing the Weather

    ERIC Educational Resources Information Center

    Crane, Peter

    2004-01-01

    Rain, sun, snow, sleet, wind... the weather affects everyone in some way every day, and observing weather is a terrific activity to attune children to the natural world. It is also a great way for children to practice skills in gathering and recording information and to learn how to use simple tools in a standardized fashion. What better way to…

  8. Weather Cardboard Carpentry

    ERIC Educational Resources Information Center

    DeBruin, Jerome E.

    1977-01-01

    Included are instructions and diagrams for building weather instruments (wind vane, Celsius temperature scale, and anemometer) from simple tools and Tri-Wall, a triple-thick corrugated cardboard. Ordering sources for Tri-Wall are listed. Additional weather instruments that can be constructed are suggested. (CS)

  9. Tracking Weather Satellites.

    ERIC Educational Resources Information Center

    Martin, Helen E.

    1996-01-01

    Describes the use of weather satellites in providing an exciting, cohesive framework for students learning Earth and space science and in providing a hands-on approach to technology in the classroom. Discusses the history of weather satellites and classroom satellite tracking. (JRH)

  10. Weatherizing a Structure.

    ERIC Educational Resources Information Center

    Metz, Ron

    This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with weatherizing a structure. Its objective is for the student to be able to analyze factors related to specific structures that indicate need for weatherizing activities and to determine steps to correct defects in structures that…

  11. Teacher's Weather Sourcebook.

    ERIC Educational Resources Information Center

    Konvicka, Tom

    This book is a teaching resource for the study of weather-related phenomena. A "weather unit" is often incorporated into school study because of its importance to our daily lives and because of its potential to cut across disciplinary content. This book consists of two parts. Part I covers the major topics of atmospheric science such as the modern…

  12. Mild and Wild Weather.

    ERIC Educational Resources Information Center

    NatureScope, 1985

    1985-01-01

    Presents background information and six activities that focus on clouds, precipitation, and stormy weather. Each activity includes an objective, recommended age level(s), subject area(s), and instructional strategies. Also provided are two ready-to-copy pages (a coloring page on lightning and a list of weather riddles to solve). (JN)

  13. Weather Fundamentals: Wind. [Videotape].

    ERIC Educational Resources Information Center

    1998

    The videos in this educational series, for grades 4-7, help students understand the science behind weather phenomena through dramatic live-action footage, vivid animated graphics, detailed weather maps, and hands-on experiments. This episode (23 minutes) describes the roles of the sun, temperature, and air pressure in creating the incredible power…

  14. World weather program

    NASA Technical Reports Server (NTRS)

    1980-01-01

    A brief description of the Global Weather Experiment is presented. The world weather watch program plan is described and includes a global observing system, a global data processing system, a global telecommunication system, and a voluntary cooperation program. A summary of Federal Agency plans and programs to meet the challenges of international meteorology for the two year period, FY 1980-1981, is presented.

  15. The Home Weather Station.

    ERIC Educational Resources Information Center

    Steinke, Steven D.

    1991-01-01

    Described is how an amateur weather observer measures and records temperature and precipitation at a well-equipped, backyard weather station. Directions for building an instrument shelter and a description of the instruments needed for measuring temperature and precipitation are included. (KR)

  16. Fabulous Weather Day

    ERIC Educational Resources Information Center

    Marshall, Candice; Mogil, H. Michael

    2007-01-01

    Each year, first graders at Kensington Parkwood Elementary School in Kensington, Maryland, look forward to Fabulous Weather Day. Students learn how meteorologists collect data about the weather, how they study wind, temperature, precipitation, basic types/characteristics of clouds, and how they forecast. The project helps the students grow in…

  17. Modeling of SO{sub 2} absorption into limestone suspensions

    SciTech Connect

    Lancia, A.; Musmarra, D.; Pepe, F.

    1997-01-01

    The wet limestone flue gas desulfurization process, and more specifically absorption of SO{sub 2} limestone suspensions, was studied. Experiments of SO{sub 2} absorption were carried out using a bubbling reactor with a mixture of sulfur dioxide and nitrogen in the gas phase and an aqueous limestone suspension in the liquid phase. The SO{sub 2} absorption rate was measured at different compositions of both gas and liquid phases and at different gas flow rates and agitator speeds. A model based on the film theory was proposed to describe liquid-side mass transfer. It was assumed that the liquid-phase diffusional resistance is concentrated in a layer, the thickness of which depends on fluid dynamics, but is independent of the nature of the reactions taking place. The equations considered by the model describe conditions of thermodynamic equilibrium as well as material and electrical balances and use the experimentally determined gas- and liquid-side mass-transfer coefficients, rather than empirical parameters. Model calculations and experimental results were compared, and a good consistency was found. Eventually the model was used to evaluate the absorption enhancement factor as a function of gas- and liquid-phase composition.

  18. Stratigraphy of the Upper Pleistocene Miami Limestone of Florida

    SciTech Connect

    Johnson, R.A.

    1993-03-01

    The upper Pleistocene Miami Limestone is probably the most stratigraphically-complex formation in the Cenozoic of Florida. The Miami overlies and vertically/laterally grades into the upper Pleistocene Ft. Thompson Formation to the west in southeast Palm Beach County (west of I-95); to the west in Broward County (west of the Turnpike); and to the north in south Broward County (along U.S. 27). The Miami overlies and very locally vertically grades into the Ft. Thompson in all of Dade County. The Miami overlies and vertically/laterally grades into the upper Pleistocene Anastasia Formation to the north and east in southeast Palm Beach County (east of I-95), and to the northeast in east Broward County (east of the Turnpike). The Miami laterally grades into the upper Pleistocene Key Largo Limestone to the southeast in extreme southeast Dade County, and overlies and locally vertically grades into the Key Largo in the Lower Keys, south Monroe County. The Miami unconformably overlies the Pliocene Tamiami Formation and pinches out to the west in northeast mainland Monroe and southeast Collier Counties, and also pinches out to the north in east-central Palm Beach County. In all areas, the Miami Limestone is either overlain unconformably by very discontinuous undifferentiated surficial sediments or forms land surface.

  19. NASA Connect: 'Plane Weather'

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Excerpt from the NASA Connect show 'Plane Weather' This clip explains what high and low pressure weather systems are, and how they form. Weather affects our daily lives. The elements of weather: rain, wind, fog, ice and snow affect the operation and flight of an airplane. In this program, NASA and FAA researchers will introduce students to math, science, and weather; demonstrate how these elements influence flight; and show how NASA and FAA research is used to limit the effects of these elements on flight. Students will examine: the tools, techniques, and technologies used by engineers and scientists to detect these and other climatological factors affecting aircraft in flight. The lesson and classroom experiment will involve students in the scientific process and emphasizing problem solving, measurement, and reasoning skills.

  20. Weather in Mountainous Terrain (Overcoming Scientific Barriers to Weather Support)

    DTIC Science & Technology

    2011-02-15

    Weather in Mountainous Terrain (Overcoming Scientific Barriers to Weather Support) Fiesta Resort & Conference Center Tempe, AZ February 1...Meteorology Overcoming Scientific Barriers to Weather Support Fiesta Resort & Conference Center Tempe, AZ February 1 & 2, 2010 Hosted by University

  1. Thermo-poroelastic response of an argillaceous limestone

    NASA Astrophysics Data System (ADS)

    Selvadurai, Patrick; Najari, Meysam

    2016-04-01

    Argillaceous limestones are now being considered by many countries that intend to develop deep geologic storage facilities for siting both high-level and intermediate- to low-level nuclear fuel wastes. In deep geologic settings for high level nuclear wastes, the heating due to radioactive decay is transmitted through an engineered barrier, which consists of the waste container and an engineered geologic barrier, which consists of an encapsulating compacted bentonite. The heat transfer process therefore leads to heating of the rock mass where the temperature of the rock is substantially lower than the surface temperature of the waste container. This permits the use of mathematical theories of poroelastic media where phase transformations, involving conversion of water to a vapour form are absent. While the thermo-poroelastic responses of geologic media such as granite and porous tuff have been investigated in the literature, the investigation of thermo-poroelastic responses of argillaceous limestones is relatively new. Argillaceous limestones are considered to be suitable candidates for siting deep geologic repositories owing to the ability to accommodate stress states with generation of severe defects that can influence their transmissivity characteristics. Also the clay fraction in such rocks can contribute to long term healing type phenomena, which is a considerable advantage. This research presents the results of a laboratory investigation and computational modelling of the same that examines the applicability of the theory of thermo-poroelasticity, which extend Biot's classical theory of poroelasticity to include uncoupled heat conduction. The experimental configuration involves the boundary heating of a cylinder of the Cobourg Limestone from southern Ontario, Canada. The cylinder measuring 150 mm in diameter and 278 mm in length contains an axisymmetric fluid-filled cylindrical cavity measuring 26 mm in diameter and 139 mm in length. Thermo-poroelastic effects

  2. Diversity of endolithic fungal communities in dolomite and limestone rocks from Nanjiang Canyon in Guizhou karst area, China.

    PubMed

    Tang, Yuan; Lian, Bin

    2012-06-01

    The endolithic environment, the tiny pores and cracks in rocks, buffer microbial communities from a number of physical stresses, such as desiccation, rapid temperature variations, and UV radiation. Considerable knowledge has been acquired about the diversity of microorganisms in these ecosystems, but few culture-independent studies have been carried out on the diversity of fungi to date. Scanning electron microscopy of carbonate rock fragments has revealed that the rock samples contain certain kinds of filamentous fungi. We evaluated endolithic fungal communities from bare dolomite and limestone rocks collected from Nanjiang Canyon (a typical karst canyon in China) using culture-independent methods. Results showed that Ascomycota was absolutely dominant both in the dolomite and limestone fungal clone libraries. Basidiomycota and other eukaryotic groups (Bryophyta and Chlorophyta) were only detected occasionally or at low frequencies. The most common genus in the investigated carbonate rocks was Verrucaria. Some other lichen-forming fungi (e.g., Caloplaca, Exophiala, and Botryolepraria), Aspergillus, and Penicillium were also identified from the rock samples. The results provide a cross-section of the endolithic fungal communities in carbonate rocks and help us understand more about the role of microbes (fungi and other rock-inhabiting microorganisms) in rock weathering and pedogenesis.

  3. Environmental Education Tips: Weather Activities.

    ERIC Educational Resources Information Center

    Brainard, Audrey H.

    1989-01-01

    Provides weather activities including questions, on weather, heating the earth's surface, air, tools of the meteorologist, clouds, humidity, wind, and evaporation. Shows an example of a weather chart activity. (RT)

  4. Weather--An Integrated Unit

    ERIC Educational Resources Information Center

    McConnell, Vivian

    1976-01-01

    Outlined is a two week unit on weather offered as independent study for sixth- and seventh-year students in Vancouver, Canada, schools. Included is a section on weather lore and a chart of weather symbols. (SL)

  5. Space Weather: Where Is The Beef?

    NASA Astrophysics Data System (ADS)

    Koskinen, H. E. J.

    Space weather has become a highly fashionable topic in solar-terrestrial physics. It is perhaps the best tool to popularise the field and it has contributed significantly to the dialogue between solar, magnetospheric, and ionospheric scientist, and also to mu- tual understanding between science and engineering communities. While these are laudable achievements, it is important for the integrity of scientific space weather re- search to recognise the central open questions in the physics of space weather and the progress toward solving them. We still lack sufficient understanding of the solar physics to be able to tell in advance when and where a solar eruption will take place and whether it will turn to a geoeffective event. There is much to do to understand ac- celeration of solar energetic particles and propagation of solar mass ejecta toward the Earth. After more than 40 years of research scientific discussion of energy and plasma transfer through the magnetopause still deals mostly with qualitative issues and the rapid acceleration processes in the magnetosphere are not yet explained in a satisfac- tory way. Also the coupling to the ionosphere and from there to the strong induction effects on ground is another complex of research problems. For space weather science the beef is in the investigation of these and related topics, not in marketing half-useful space weather products to hesitant customers.

  6. Timing of natural remanent magnetization in ferriferous limestones from the Swiss Jura mountains

    NASA Astrophysics Data System (ADS)

    Gehring, Andreas U.; Heller, Friedrich

    1989-06-01

    Goethite and hematite are the main magnetic phases contained in two ferriferous middle Jurassic beds which are exposed within the Mandach structure, the major tectonic structure of the eastern tabular Jura of northern Switzerland. The iron oxidic phases in a reddish brown sparry limestone known as Spatkalk were formed diagenetically, whereas these phases are weathering products in a stratigraphically slightly younger oolitic bed. The hematite in the oolitic bed was magnetized after the Jura main tectonic event in the Miocene whereas the hematite in the Spatkalk was magnetized before the Miocene. The goethites in the oolitic bed carry a pretectonic and in the Spatkalk a syntectonic magnetization. Physical and chemical data show that the goethite which was resistant to remagnetization contains an Al-substitution of 3.4 mol% resulting in a Néel temperature of 90°C. The remagnetized goethite has an Al-content of 10.7 mol% and a Néel temperature of 70°C. The different goethite properties indicate that the tectonic formation of the Mandach structure occurred under low-temperature conditions below 90°C.

  7. Modeling rock weathering in small watersheds

    NASA Astrophysics Data System (ADS)

    Pacheco, Fernando A. L.; Van der Weijden, Cornelis H.

    2014-05-01

    Many mountainous watersheds are conceived as aquifer media where multiple groundwater flow systems have developed (Tóth, 1963), and as bimodal landscapes where differential weathering of bare and soil-mantled rock has occurred (Wahrhaftig, 1965). The results of a weathering algorithm (Pacheco and Van der Weijden, 2012a, 2014), which integrates topographic, hydrologic, rock structure and chemical data to calculate weathering rates at the watershed scale, validated the conceptual models in the River Sordo basin, a small watershed located in the Marão cordillera (North of Portugal). The coupling of weathering, groundwater flow and landscape evolution analyses, as accomplished in this study, is innovative and represents a remarkable achievement towards regionalization of rock weathering at the watershed scale. The River Sordo basin occupies an area of approximately 51.2 km2 and was shaped on granite and metassediment terrains between the altitudes 185-1300 m. The groundwater flow system is composed of recharge areas located at elevations >700 m, identified on the basis of δ18O data. Discharge cells comprehend terminations of local, intermediate and regional flow systems, identified on the basis of spring density patterns, infiltration depth estimates based on 87Sr/86Sr data, and spatial distributions of groundwater pH and natural mineralization. Intermediate and regional flow systems, defined where infiltration depths >125 m, develop solely along the contact zone between granites and metassediments, because fractures in this region are profound and their density is very large. Weathering is accelerated where rocks are covered by thick soils, being five times faster relative to sectors of the basin where rocks are covered by thin soils. Differential weathering of bare and soil-mantled rock is also revealed by the spatial distribution of calculated aquifer hydraulic diffusivities and groundwater travel times.

  8. Selected Data for Wells and Test Holes Used in Structure-Contour Maps of the Inyan Kara Group, Minnekahta Limestone, Minnelusa Formation, Madison Limestone, and Deadwood Formation in the Black Hills Area, South Dakota

    DTIC Science & Technology

    1999-01-01

    Selected Data for Wells and Test Holes Used in Structure-Contour Maps of the Inyan Kara Group, Minnekahta Limestone, Minnelusa Formation, Madison...Test Holes Used in Structure-Contour Maps of the Inyan Kara Group, Minnekahta Limestone, Minnelusa Formation, Madison Limestone, and Deadwood Formation...Structure-Contour Maps of the Inyan Kara Group, Minnekahta Limestone, Minnelusa Formation, Madison Limestone, and Deadwood Formation in the Black Hills Area

  9. Weathering in a Cup.

    ERIC Educational Resources Information Center

    Stadum, Carol J.

    1991-01-01

    Two easy student activities that demonstrate physical weathering by expansion are described. The first demonstrates ice wedging and the second root wedging. A list of the needed materials, procedure, and observations are included. (KR)

  10. National Weather Service

    MedlinePlus

    ... SAFETY Floods Tsunami Beach Hazards Wildfire Cold Tornadoes Air Quality Fog Heat Hurricanes Lightning Safe Boating Rip Currents ... ACTIVE ALERTS FORECAST MAPS RADAR RIVERS, LAKES, RAINFALL AIR QUALITY SATELLITE PAST WEATHER " ); }); American Samoa Guam Puerto Rico/ ...

  11. Weather Information Processing

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Science Communications International (SCI), formerly General Science Corporation, has developed several commercial products based upon experience acquired as a NASA Contractor. Among them are METPRO, a meteorological data acquisition and processing system, which has been widely used, RISKPRO, an environmental assessment system, and MAPPRO, a geographic information system. METPRO software is used to collect weather data from satellites, ground-based observation systems and radio weather broadcasts to generate weather maps, enabling potential disaster areas to receive advance warning. GSC's initial work for NASA Goddard Space Flight Center resulted in METPAK, a weather satellite data analysis system. METPAK led to the commercial METPRO system. The company also provides data to other government agencies, U.S. embassies and foreign countries.

  12. Weathering of Martian Evaporites

    NASA Technical Reports Server (NTRS)

    Wentworth, S. J.; Velbel, M. A.; Thomas-Keprta, K. L.; Longazo, T. G.; McKay, D. S.

    2001-01-01

    Evaporites in martian meteorites contain weathering or alteration features that may provide clues about the martian near-surface environment over time. Additional information is contained in the original extended abstract.

  13. Weather Radar Studies.

    DTIC Science & Technology

    1985-03-31

    National Center for Atmospheric Research JAWS program and the National Severe Storms Laboratory are being analyzed to develop low-altitude wind shear...public through low-altitude wind shear aviation weather products the National Technical Information Service, NEXR I turbulence., Springfield, VA 22161. 19...were analyzed preliminarily to determine wind shear characteristics in the Memphis area. Doppler weather radar data from the National Center for

  14. The operational user of weather data in the information age

    SciTech Connect

    D`Aleo, J.

    1995-12-31

    We are in the midst of an information explosion in meteorology. The operational user working with computer systems and satellite delivery of weather data today receives as much data in one 8-hour shift as an advanced user in the 1950`s would have received in 40 years (an entire career!). And the changes are accelerating. Spurred on by the National Weather Service`s modernization program, an additional 20 to 50 fold increase in data volumes from today`s levels can be expected by the year 2000. This paper describes the sources of the data, value-added products available, the weather workstation, and how to benefit from the information provided.

  15. Genetically optimizing weather predictions

    NASA Astrophysics Data System (ADS)

    Potter, S. B.; Staats, Kai; Romero-Colmenero, Encarni

    2016-07-01

    humidity, air pressure, wind speed and wind direction) into a database. Built upon this database, we have developed a remarkably simple approach to derive a functional weather predictor. The aim is provide up to the minute local weather predictions in order to e.g. prepare dome environment conditions ready for night time operations or plan, prioritize and update weather dependent observing queues. In order to predict the weather for the next 24 hours, we take the current live weather readings and search the entire archive for similar conditions. Predictions are made against an averaged, subsequent 24 hours of the closest matches for the current readings. We use an Evolutionary Algorithm to optimize our formula through weighted parameters. The accuracy of the predictor is routinely tested and tuned against the full, updated archive to account for seasonal trends and total, climate shifts. The live (updated every 5 minutes) SALT weather predictor can be viewed here: http://www.saao.ac.za/ sbp/suthweather_predict.html

  16. Cockpit weather information system

    NASA Technical Reports Server (NTRS)

    Tu, Jeffrey Chen-Yu (Inventor)

    2000-01-01

    Weather information, periodically collected from throughout a global region, is periodically assimilated and compiled at a central source and sent via a high speed data link to a satellite communication service, such as COMSAT. That communication service converts the compiled weather information to GSDB format, and transmits the GSDB encoded information to an orbiting broadcast satellite, INMARSAT, transmitting the information at a data rate of no less than 10.5 kilobits per second. The INMARSAT satellite receives that data over its P-channel and rebroadcasts the GDSB encoded weather information, in the microwave L-band, throughout the global region at a rate of no less than 10.5 KB/S. The transmission is received aboard an aircraft by means of an onboard SATCOM receiver and the output is furnished to a weather information processor. A touch sensitive liquid crystal panel display allows the pilot to select the weather function by touching a predefined icon overlain on the display's surface and in response a color graphic display of the weather is displayed for the pilot.

  17. Color measurements on marble and limestone briquettes exposed to outdoor environment in the Eastern United States. Volume I: Results of exposure 1984-1990

    SciTech Connect

    Reimann, K.J.

    1994-04-01

    In a long-term program that began in 1984, limestone and marble briquettes have been exposed to both anthropogenic acid deposition and natural weathering at four field sites in the eastern United States. Similar tests began at an Ohio site in 1986. Effects of exposure on the briquettes and other materials at the sites are evaluated periodically by several federal agencies cooperating in the National Acid Precipitation Assessment Program (NAPAP). One of the primary contributions of Argonne National Laboratory to the NAPAP has been the measurement of tristimulus color change on samples exposed to the environment. Results from the first six years indicate a yellowing of the marble and a darkening of limestone on both the skyward and groundward surfaces of fresh and preexposed briquettes. The relationship between discoloration and exposure period appears to be linear. Discoloration rates as a function of a cumulative exposure time are almost constant for marble and slightly decreasing for limestone Dark spots on groundward surfaces were measured with tristimulus color equipment prior to chemical analysis to determine if a correlation exists between darkening (change in reflectance) and SO{sub 4} concentration. Taking exposure time into consideration, and assuming that the airborne concentration of dark particles, which cause darkening, is proportional to airborne SO{sub 2} concentration, one can establish a linear relationship between exposure time, darkening, and SO{sub 2} concentration. The program is continuing so that additional data can be obtained.

  18. {sup 13}C chemical shift anisotropies for carbonate ions in cement minerals and the use of {sup 13}C, {sup 27}Al and {sup 29}Si MAS NMR in studies of Portland cement including limestone additions

    SciTech Connect

    Sevelsted, Tine F.; Herfort, Duncan

    2013-10-15

    {sup 13}C isotropic chemical shifts and chemical shift anisotropy parameters have been determined for a number of inorganic carbonates relevant in cement chemistry from slow-speed {sup 13}C MAS or {sup 13}C({sup 1}H) CP/MAS NMR spectra (9.4 T or 14.1 T) for {sup 13}C in natural abundance. The variation in the {sup 13}C chemical shift parameters is relatively small, raising some doubts that different carbonate species in Portland cement-based materials may not be sufficiently resolved in {sup 13}C MAS NMR spectra. However, it is shown that by combining {sup 13}C MAS and {sup 13}C({sup 1}H) CP/MAS NMR carbonate anions in anhydrous and hydrated phases can be distinguished, thereby providing valuable information about the reactivity of limestone in cement blends. This is illustrated for three cement pastes prepared from an ordinary Portland cement, including 0, 16, and 25 wt.% limestone, and following the hydration for up to one year. For these blends {sup 29}Si MAS NMR reveals that the limestone filler accelerates the hydration for alite and also results in a smaller fraction of tetrahedrally coordinated Al incorporated in the C-S-H phase. The latter result is more clearly observed in {sup 27}Al MAS NMR spectra of the cement–limestone blends and suggests that dissolved aluminate species in the cement–limestone blends readily react with carbonate ions from the limestone filler, forming calcium monocarboaluminate hydrate. -- Highlights: •{sup 13}C chemical shift anisotropies for inorganic carbonates from {sup 13}C MAS NMR. •Narrow {sup 13}C NMR chemical shift range (163–171 ppm) for inorganic carbonates. •Anhydrous and hydrated carbonate species by {sup 13}C MAS and {sup 13}C({sup 1}H) CP/MAS NMR. •Limestone accelerates the hydration for alite in Portland – limestone cements. •Limestone reduces the amount of aluminium incorporated in the C-S-H phase.

  19. Penetration into limestone targets with ogive-nose steel projectiles

    SciTech Connect

    Frew, D.J.; Green, M.L.; Forrestal, M.J.; Hanchak, S.J.

    1996-12-01

    We conducted depth of penetration experiments into limestone targets with 3.0 caliber-radius-head, 4340 Rc 45 steel projectiles. Powder guns launched two projectiles with length-to-diameter ratios of ten to striking velocities between 0.4 and 1.5 km/s. Projectiles had diameters and masses of 12.7 mm, 0. 117 kg and 25.4 mm, 0.610 kg. Based on data sets with these two projectile scales, we proposed an empirical penetration equation that described the target by its density and an empirical strength constant determined from penetration depth versus striking velocity data.

  20. Elucidation of denitrification mechanism in karstic Ryukyu limestone aquifer

    NASA Astrophysics Data System (ADS)

    Hijikawa, K.

    2014-12-01

    Nitrate (NO3-) concentrations in public water supplies have risen above acceptable levels in many areas of the world including Japan, largely as a result of contamination by human and animal waste and overuse of fertilizers. A previous study has characterized nitrate concentrations in groundwater in this area is a higher than the upper value (44mgL-1) of environmental quality criteria on one hands. On the other hand, there exists points where the concentration of nitric acid is not detected, which suggests the possibility of denitrification. During early 2000, a new analytical procedure for nitrate isotopic measurement, termed the "denitrifier method", was established. With the development of the nitrate isotope tracer method, much research has been reported detailing sources of groundwater nitrate and denitrification mechanisms. This study presents a pilot case study (in the southern part of Okinawa Main Island, Japan, where Ryukyu limestone is extensively distributed) using the combined stable isotope ratios of major elements (C, N and S) as net recorders of the biogeochemical reactions with the aim of elucidation of denitrification mechanism in Ryukyu limestone aquifer. As a result, significant decreases in nitrate concentrations due to denitrification were observed in groundwater at some locations, which induced increases in isotope ratios up to 59.7‰ for δ15NNO3. These points of groundwater were located above the cutoff wall of the underground dam and near the fault. It is considered that the residence time of the groundwater is longer than the other points at these denitrification points, and that reduction condition tends to be formed in the groundwater. However, the rapid rise of the groundwater level due to rainfall is likely to occur in the Ryukyu limestone aquifer, where the ground water was found to have changed dynamically from the reduction condition to the oxidation condition which a denitrification (has not occured)does not occur. Moreover, the

  1. Tracers in rainfall simulation experiments to study the onset of the wet season in Eastern Mediterranean limestone environments

    NASA Astrophysics Data System (ADS)

    Lange, Jens

    2010-05-01

    The eastern Mediterranean rainfall regime is characterized by dry and hot summers and rainy cold winters. In this climate rocky limestone environments are regarded as major recharge zones due to (a) intensively enlarged fissures by solution weathering and (b) sparse vegetation and shallow soils which limit evapotranspiration losses. However, relatively little is known on hydrological processes during high magnitude rainstorms, which, at the beginning of the rainy season, may occur on both dry and wet soils. These conditions were investigated by a series of sprinkling experiments during two successive days. Rainfall was applied on large plots (143 and 180 m2) to include the variety of different terrain elements (rocky outcrops, bare soil, different vegetation). Sprinkling units were located at each corner of the plot and supplemented by additional ones to balance wind drift. This sprinkling set-up did not guarantee a uniform distribution of applied rainfall, as overlap of sprinkling areas could not be prevented. To assess the spatial rainfall distribution, a large number of totalizers was necessary. During two days of sprinkling these totalizers were regularly measured and spatially interpolated across the plot. The temporal rainfall distribution, a series of two high intensity storms on dry and wet soil, was observed by a tipping bucket raingauge. Tracers were added to the sprinkling water to obtain additional process insights. By end member mixing analysis the contribution of different water types (pre-sprinkling, first day, second day) could be quantified. The first plot was located on a steep rocky hillslope. Significantly different concentration of chloride, nitrate and sulfate in the sprinkling waters helped to identify first day's water in second day's runoff. Surface runoff was a combination of infiltration excess runoff from rocky portions of the plot and saturation excess runoff from areas covered by soil. Soil saturation was accelerated by lateral runoff

  2. Solar Radio Bursts and Space Weather

    NASA Technical Reports Server (NTRS)

    Gopalswamy, Natchimuthuk,

    2012-01-01

    Radio bursts from the Sun are produced by electron accelerated to relativistic energies by physical processes on the Sun such as solar flares and coronal mass ejections (CMEs). The radio bursts are thus good indicators of solar eruptions. Three types of nonthermal radio bursts are generally associated with CMEs. Type III bursts due to accelerated electrons propagating along open magnetic field lines. The electrons are thought to be accelerated at the reconnection region beneath the erupting CME, although there is another view that the electrons may be accelerated at the CME-driven shock. Type II bursts are due to electrons accelerated at the shock front. Type II bursts are also excellent indicators of solar energetic particle (SEP) events because the same shock is supposed accelerate electrons and ions. There is a hierarchical relationship between the wavelength range of type /I bursts and the CME kinetic energy. Finally, Type IV bursts are due to electrons trapped in moving or stationary structures. The low frequency stationary type IV bursts are observed occasionally in association with very fast CMEs. These bursts originate from flare loops behind the erupting CME and hence indicate tall loops. This paper presents a summary of radio bursts and their relation to CMEs and how they can be useful for space weather predictions.

  3. DOPPLER WEATHER SYSTEM

    SciTech Connect

    Berlin, Gary J.

    2002-08-05

    The SRS Doppler Weather System consists of a Doppler Server, A Master Server (also known as the Weather Server), several Doppler Slave Servers, and client-side software program called the Doppler Radar Client. This system is used to display near rel-time images taken from the SRS Weather Center's Doppler Radar computer. The Doppler Server is software that resides on the SRS Doppler Computer. It gathers raw data, 24-bit color weather images via screen scraping ever five minutes as requested by the Master Server. The Doppler Server then reduces the 24-bit color images to 8-bit color using a fixed color table for analysis and compression. This preserves the fidelity of the image color and arranges the colors in specific order for display. At the time of color reduction, the white color used for the city names on the background images are remapped to a different index (color) of white that the white on the weather scale. The Weather Server places a time stamp on the image, then compresses the image and passes it to all Doppler Slave servers. Each of the Doppler Slave servers mainitain a circular buffer of the eight most current images representing the last 40 minutes of weather data. As a new image is added, the oldest drops off. The Doppler Radar Client is an optional install program for any site-wide workstation. When a Client session is started, the Client requests Doppler Slave server assignment from the Master Server. Upon its initial request to the Slave Server, the Client obtains all eight current images and maintains its own circular buffer, updating its images every five minutes as the Doppler Slave is updated. Three background reference images are stored as part of the Client. The Client brings up the appropriate background image, decompresses the doppler data, and displays the doppler data on the background image.

  4. Atmospheric CO2 Removal by Enhancing Weathering

    NASA Astrophysics Data System (ADS)

    Koster van Groos, A. F.; Schuiling, R. D.

    2014-12-01

    The increase of the CO2 content in the atmosphere by the release of anthropogenic CO2 may be addressed by the enhancement of weathering at the surface of the earth. The average emission of mantle-derived CO2 through volcanism is ~0.3 Gt/year (109 ton/year). Considering the ~3.000 Gt of CO2 present in the atmosphere, the residence time of CO2 in the earth's atmosphere is ~10,000 years. Because the vast proportion of carbon in biomass is recycled through the atmosphere, CO2 is continuously removed by a series of weathering reactions of silicate minerals and stored in calcium and magnesium carbonates. The addition of anthropogenic CO2 from fossil fuel and cement production, which currently exceeds 35 Gt/year and dwarfs the natural production 100-fold, cannot be compensated by current rates of weathering, and atmospheric CO2 levels are rising rapidly. To address this increase in CO2 levels, weathering rates would have to be accelerated on a commensurate scale. Olivine ((Mg,Fe)2SiO4) is the most reactive silicate mineral in the weathering process. This mineral is the major constituent in relatively common ultramafic rocks such as dunites (olivine content > 90%). To consume the current total annual anthropogenic release of CO2, using a simplified weathering reaction (Mg2SiO4 + 4CO2 + 4H2O --> 2 Mg2+ + 4HCO3- + H4SiO4) would require ~30 Gt/year or ~8-9 km3/year of dunite. This is a large volume; it is about double the total amount of ore and gravel currently mined (~ 17 Gt/year). To mine and crush these rocks to <100 μm costs ~ 8/ton. The transport and distribution over the earth's surface involves additional costs, that may reach 2-5/ton. Thus, the cost of remediation for the release of anthropogenic CO2 is 300-400 billion/year. This compares to a 2014 global GDP of ~80 trillion. Because weathering reactions require the presence of water and proceed more rapidly at higher temperatures, the preferred environments to enhance weathering are the wet tropics. From a socio

  5. Analysis of medieval limestone sculpture from southwestern France and the Paris Basin by NAA

    SciTech Connect

    Holmes, L.; Harbottle, G.

    1994-12-31

    Compositional characterization of limestone from sources known to medieval craftsmen and from the monuments they built can be used in conjunction with stylistic and iconographic criteria to infer geographic origin of sculptures that have lost their histories. Limestone from 47 quarrying locations in France and from numerous medieval monuments have been subjected to neutron activation analysis (NAA) to form the nucleus of the Brookhaven Limestone Database. Even though the method and techniques of NAA are well established, this paper briefly summarizes the parameters and experimental conditions useful for determining those concentration variables for which limestone from different sources exhibits significant and reproducible differences.

  6. Limestones of western Newfoundland that magnetized before Devonian folding but after Middle Ordovician lithification

    SciTech Connect

    Hodych, J.P. )

    1989-01-01

    A positive fold test and a negative conglomerate test help determine when and how stable remanence was acquired in the Middle Ordovician Table Head Group limestones of the Port au Port Peninsula of Newfoundland. The limestones magnetized after lithification and incorporation as clasts into a Middle Ordovician breccia. Hence, the limestones do not carry a detrital or other primary remanence despite their very low conodont color alteration index. The remanence may be thermoviscous or diagenetic and was acquired before Devonian folding. This suggests the need for caution in interpreting paleomagnetic results from other early Paleozoic limestones whose remanence resides in magnetite of blocking temperature lower than 400C.

  7. Hydrogeology of the gray limestone aquifer in southern Florida

    USGS Publications Warehouse

    Reese, Ronald S.; Cunningham, Kevin J.

    2000-01-01

    Results from 35 new test coreholes and aquifer-test, water-level, and water-quality data were combined with existing hydrogeologic data to define the extent, thickness, hydraulic properties, and degree of confinement of the gray limestone aquifer in southern Florida. This aquifer, previously known to be present only in southeastern Florida (Miami-Dade, Broward, and Palm Beach Counties) below, and to the west of, the Biscayne aquifer, extends over most of central-south Florida, including eastern and central Collier County and southern Hendry County; it is the same as the lower Tamiami aquifer to the north, and it becomes the water-table aquifer and the upper limestone part of the lower Tamiami aquifer to the west. The aquifer generally is composed of gray, shelly, lightly to moderately cemented limestone with abundant shell fragments or carbonate sand, abundant skeletal moldic porosity, and minor quartz sand. The gray limestone aquifer comprises the Ochopee Limestone of the Tamiami Formation, and, in some areas, the uppermost permeable part of an unnamed formation principally composed of quartz sand. Underlying the unnamed formation is the Peace River Formation of the upper Hawthorn Group, the top of which is the base of the surficial aquifer system. Overlying the aquifer and providing confinement in much of the area is the Pinecrest Sand Member of the Tamiami Formation. The thickness of the aquifer is comparatively uniform, generally ranging from 30 to 100 feet. The unnamed formation part of the aquifer is up to 20 feet thick. The Ochopee Limestone accumulated in a carbonate ramp depositional system and contains a heterozoan carbonate-particle association. The principal rock types of the aquifer are pelecypod lime rudstones and floatstones and permeable quartz sands and sandstones. The pore types are mainly intergrain and separate vug (skeletal-moldic) pore spaces. The rock fabric and associated primary and secondary pore spaces combine to form a dual diffuse

  8. Rare earths in the Leadville Limestone and its marble derivates

    USGS Publications Warehouse

    Jarvis, J.C.; Wildeman, T.R.; Banks, N.G.

    1975-01-01

    Samples of unaltered and metamorphosed Leadville Limestone (Mississippian, Colorado) were analyzed by neutron activation for ten rare-earth elements (REE). The total abundance of the REE in the least-altered limestone is 4-12 ppm, and their distribution patterns are believed to be dominated by the carbonate minerals. The abundances of the REE in the marbles and their sedimentary precursors are comparable, but the distribution patterns are not. Eu is enriched over the other REE in the marbles, and stratigraphically upward in the formation (samples located progressively further from the heat source), the light REE become less enriched relative to the heavy REE. The Eu anomaly is attributed to its ability, unique among the REE, to change from the 3+ to 2+ oxidation state. Whether this results in preferential mobilization of the other REE or whether this reflects the composition of the pore fluid during metamorphism is unknown. Stratigraphically selective depletion of the heavy REE may be attributed to more competition for the REE between fluid and carbonate minerals in the lower strata relative to the upper strata. This competition could have been caused by changes in the temperature of the pore fluid or to the greater resistance to solution of the dolomite in the lower parts of the formation than the calcite in the upper parts. ?? 1975.

  9. Bird species diversity in the padawan limestone area, sarawak.

    PubMed

    Mansor, Mohammad Saiful; Sah, Shahrul Anuar Mohd; Koon, Lim Chan; Rahman, Mustafa Abdul

    2011-12-01

    Bird surveys were conducted in the Padawan Limestone Area for seven days at each of two study sites, Giam and Danu, from August to December 2008. The purpose of the study was to compare the area's bird species richness and abundance of bird species in other limestone areas and in other forest types. The study also compared the species richness and relative abundance of birds in undisturbed and disturbed areas at both study sites. Twenty mist nets were deployed for 12 hours daily. During this study period, direct observations of birds were also made. In all, 80 species from 34 families were recorded at both sites. At Giam, 120 birds were mist-netted. These birds represented 31 species from 16 families. The direct observations at Giam recorded 13 species from 11 families. In the undisturbed area, 21 species from 13 families were mist-netted, whereas in the disturbed area, 21 species from 10 families were mist-netted. In Danu, a total of 48 birds, representing 25 species from 12 families, were mist-netted. The observations at Danu recorded 34 species from 19 families. Twelve species from 7 families were mist-netted in the undisturbed area, whereas 18 species from 11 families were mist-netted in the disturbed area. Statistical analysis showed that the species diversity index differed significantly between undisturbed and disturbed areas.

  10. Bird Species Diversity in the Padawan Limestone Area, Sarawak

    PubMed Central

    Mansor, Mohammad Saiful; Sah, Shahrul Anuar Mohd; Koon, Lim Chan; Rahman, Mustafa Abdul

    2011-01-01

    Bird surveys were conducted in the Padawan Limestone Area for seven days at each of two study sites, Giam and Danu, from August to December 2008. The purpose of the study was to compare the area’s bird species richness and abundance of bird species in other limestone areas and in other forest types. The study also compared the species richness and relative abundance of birds in undisturbed and disturbed areas at both study sites. Twenty mist nets were deployed for 12 hours daily. During this study period, direct observations of birds were also made. In all, 80 species from 34 families were recorded at both sites. At Giam, 120 birds were mist-netted. These birds represented 31 species from 16 families. The direct observations at Giam recorded 13 species from 11 families. In the undisturbed area, 21 species from 13 families were mist-netted, whereas in the disturbed area, 21 species from 10 families were mist-netted. In Danu, a total of 48 birds, representing 25 species from 12 families, were mist-netted. The observations at Danu recorded 34 species from 19 families. Twelve species from 7 families were mist-netted in the undisturbed area, whereas 18 species from 11 families were mist-netted in the disturbed area. Statistical analysis showed that the species diversity index differed significantly between undisturbed and disturbed areas. PMID:24575218

  11. Computerized Shawnee lime/limestone scrubbing model users manual

    SciTech Connect

    Anders, W.L.; Torstrick, R.L.

    1981-03-01

    The manual gives a general description of a computerized model for estimating design and cost of lime or limestone scrubber systems for flue gas desulfurization (FGD). It supplements PB80-123037 by extending the number of scrubber options which can be evaluated. It includes spray tower and venturi/spray-tower absorbers, forced oxidation systems, systems with absorber loop additives (MgO or adipic acid), revised design and economic premises, and other changes reflecting process improvements and variations. It describes all inputs and outputs, along with detailed procedures for using the model and all its options. The model is based on prototype scrubber data from the EPA/Shawnee test facility and should be useful to utility companies, as well as to architectural and engineering contractors who are involved in selecting and designing FGD facilities. As key features, the model provides estimates of capital investment and operating revenue requirements. It also provides a material balance, equipment list, and a breakdown of costs by processing areas. The primary uses of the model are to project comparative economics of lime and limestone FGD processes and to evaluate system alternatives prior to the development of a detailed design.

  12. Limestones distinguished by magnetic hysteresis in three-dimensional projections

    NASA Astrophysics Data System (ADS)

    Borradaile, G. J.; Hamilton, Tom

    2003-09-01

    Magnetic hysteresis data determine the suitability of rocks for paleomagnetic work, provide clues to paleo-environment and paleo-climate and they may characterize depositional environments for limestones. However, the variables chosen for conventional two-dimensional hysteresis plots, such as that of Day et al. [1977], are not always suitable to discriminate between samples. Distinguishing samples by their regression surfaces in 3D hysteresis space may be more successful in some cases [Borradaile and Lagroix, 2000] but a 2D projection with a less arbitrary viewing axis is preferable for routine reporting. We show that limestone samples are simply discriminated in a new 2D projection produced by projecting hysteresis data from three dimensions (x, y, z = Mr/Ms, Bcr, Bc) onto a plane containing the Mr/Ms axis. The orientation of the plane is controlled by its x-axis that is defined by a suitably selected Bcr/Bc ratio, most often in the magnetite PSD range, 2< (Bcr/Bc) < 4.

  13. Colmenar limestone as a resource for built heritage

    NASA Astrophysics Data System (ADS)

    Fort, Rafael; Álvarez de Buergo, Mónica; Varas-Muriel, MªJosé; Mercedes Pérez-Monserrat, Elena

    2013-04-01

    The Colmenar stone (or Colmenar limestone) has been used in the construction of significant builidings of the Central area of Spain, such as the Royal Palace of Aranjuez (16th -18th centuries) or the Royal Palace of Madrid (18th century). Nowadays this building stone is still widely used, both for new construction and restoration works, as well as for the indoor ornamentation of emblematic buildings such as the Royal Theater of Madrid (20th century). There are many quarries from where this stone was exploited, being the most prestigious ones those located in Colmenar de Oreja, at 50 km Southeast the city of Madrid. The high quality of the stone in these quarries, its whiteness and pureness, made this locality the most relevant in these stonés extractive activities, concentrating the most relevant exploitations and providing the stone the denomination of the municipality (Colmenar). It was an underground mining extraction until the 20th century in order to reach the highest quality level of the mine, the so called "Banco Gordo" (Thick Bank). Generically known as moorland limestone, this rock belongs to the fluvial-lacustrine carbonates of the Upper Miocene Unit of the Tertiary Madrid's Basin. Its tonality mainly ranges from white to cream and even light grey. Under a petrographic point of view, this limestone is constituted by 40% of bioclasts (characea, ostracods and gasteropods), 20-30% of micritic matrix and 30-40% of sparitic cement. Therefore, it can be classified as a biomicrite/biosparite limestone or as a bioclastic packstone. Some particularities of these limestones regarding their appearance are related to some karstic processes they underwent linked to some dissolution phenomena during the Pliocene. All of this resulted on an abundance of cavities with terra rossa fillings, a non-soluble clayey residue, iron enriched, which is the responsible for the reddish and pinkish color that the Colmenar stone sometimes shows. These petrographic characteristics

  14. GPR investigations in galleries buried inside a karstified limestone formation

    NASA Astrophysics Data System (ADS)

    Rousset, D.; Sénéchal, G.; Gaffet, S.

    2009-04-01

    A large scientific program of geophysical investigations is presently performed inside the Low-Noise Underground Laboratory (Laboratoire Souterrain à Bas Bruit / LSBB, Rustrel, France) which is an decomissioned underground missile control center, buried in a karstified limestone formation. One of the goals of this project is the understanding of the water circulation inside the structure. This experimental site offers a unique opportunity of perfoming measurements within an unweathered limestone massif. The tunnel has been dug in lower cretaceous limestone which is characterized by a low clay content, high electrical resistivity. The dip is around 25 degrees and vertical faults locally affect the structure. The studied zone is located in south-eastern France (Provence) and is characterized by a mediterranean climate with long dry periods and strong, short events of rain. This phenomenon induces large variations of water content within the karstified limestone from dry to saturated conditions. Analysis of the spatial and temporal variations of the water flow in a karstified limestones needs to define the geological context and the adequate geophysical methods. GPR offers a good tradeoff between resolution and ease of use on one hand and investigation depth on the other hand. We present some GPR profiles which have been acquired in April 2008 after a quite long and strong period of rain, inducing a complete water saturation inside the karstified massif. We used several RAMAC shielded antennas from 100 to 500 MHz. The longest profile is around 600 m long, with a 20 cm spacing, running from a raw to a concrete gallery. These data sets are characterized by a very good signal to noise ratio and a signal penetration, up to 18 meters. Signal processing includes very low frequency filtering, amplitude compensation, keeping lateral relative attenuation and ringing suppression. Final sections includes migration and time to depth conversion or depth migration. The estimated

  15. New weather index

    NASA Astrophysics Data System (ADS)

    Scientists at the National Oceanic and Atmospheric Administration (NOAA) and the University of Delaware have refined the wind-chill factor, a common measurement of weather discomfort, into a new misery register called the weather stress index. In addition to the mix of temperature and wind speed data used to calculate wind chill, the recipe for the index adds two new ingredients—humidity and a dash of benchmark statistics—to estimate human reaction to weather conditions. NOAA says that the weather stress index estimates human reaction to weather conditions and that the reaction depends on variations from the ‘normal’ conditions in the locality involved.Discomfort criteria for New Orleans, La., and Bismarck, N.D., for example, differ drastically. According to NOAA, when it's the middle of winter and it's -10°C with a relative humidity of 80% and 24 km/h winds, persons in New Orleans would be highly stressed while those in Bismarck wouldn't bat an eye.

  16. Weather from the Stratosphere?

    NASA Technical Reports Server (NTRS)

    Baldwin, Mark P.; Thompson, David W. J.; Shuckburgh, Emily F.; Norton, Warwick A.; Gillett, Nathan P.

    2006-01-01

    Is the stratosphere, the atmospheric layer between about 10 and 50 km, important for predicting changes in weather and climate? The traditional view is that the stratosphere is a passive recipient of energy and waves from weather systems in the underlying troposphere, but recent evidence suggests otherwise. At a workshop in Whistler, British Columbia (1), scientists met to discuss how the stratosphere responds to forcing from below, initiating feedback processes that in turn alter weather patterns in the troposphere. The lowest layer of the atmosphere, the troposphere, is highly dynamic and rich in water vapor, clouds, and weather. The stratosphere above it is less dense and less turbulent (see the figure). Variability in the stratosphere is dominated by hemispheric-scale changes in airflow on time scales of a week to several months. Occasionally, however, stratospheric air flow changes dramatically within just a day or two, with large-scale jumps in temperature of 20 K or more. The troposphere influences the stratosphere mainly through atmospheric waves that propagate upward. Recent evidence shows that the stratosphere organizes this chaotic wave forcing from below to create long-lived changes in the stratospheric circulation. These stratospheric changes can feed back to affect weather and climate in the troposphere.

  17. Limestone fluidized bed treatment of acid-impacted water at the Craig Brook National Fish Hatchery, Maine, USA

    USGS Publications Warehouse

    Sibrell, P.L.; Watten, B.J.; Haines, T.A.; Spaulding, B.W.

    2006-01-01

    Decades of atmospheric acid deposition have resulted in widespread lake and river acidification in the northeastern U.S. Biological effects of acidification include increased mortality of sensitive aquatic species such as the endangered Atlantic salmon (Salmo salar). The purpose of this paper is to describe the development of a limestone-based fluidized bed system for the treatment of acid-impacted waters. The treatment system was tested at the Craig Brook National Fish Hatchery in East Orland, Maine over a period of 3 years. The product water from the treatment system was diluted with hatchery water to prepare water supplies with three different levels of alkalinity for testing of fish health and survival. Based on positive results from a prototype system used in the first year of the study, a larger demonstration system was used in the second and third years with the objective of decreasing operating costs. Carbon dioxide was used to accelerate limestone dissolution, and was the major factor in system performance, as evidenced by the model result: Alk = 72.84 ?? P(CO2)1/2; R2 = 0.975. No significant acidic incursions were noted for the control water over the course of the study. Had these incursions occurred, survivability in the untreated water would likely have been much more severely impacted. Treated water consistently provided elevated alkalinity and pH above that of the hatchery source water. ?? 2005 Elsevier B.V. All rights reserved.

  18. X-radiography of trace fossils in limestones and dolostones from the Jurassic Smackover Formation, south Alabama

    SciTech Connect

    Esposito, R.A.; Castleman, S.P.; King, D.T. Jr.

    1985-01-01

    X-radiography has been useful in studying biogenic sedimentary structures in unconsolidated sediments but the technique has not been applied often to the study of hard carbonate rock. The authors have applied x-radiography to the study of the lower part of the Smackover to enhance the complete petrologic description of the rock. The lower Smackover has many dense micrite intervals and intervals of monotonous, thin graded beds. Parts of the lower Smackover is also dolomitized. None of the above rocks contains significant amount of skeletal debris and trace fossils are not generally obvious in an etched slab of core. In limestone, they have detected well-preserved trace fossils by x-radiography, however. The dolostones show no traces using our method. In limestones, the traces are marked by minute amounts of finely divided iron sulfides. This causes a slight density difference resulting in greater x-ray absorption. They recognize two main trace-fossil types: a Thalassinoides best seen in slabs cut parallel to bedding and a Zoophycos best seen in slabs cut perpendicular to bedding. The technique requires a slab cut 8 mm thick with parallel flat surfaces and a medical x-ray unit using accelerating voltages of 66 kV and 10 mas. Traces are most successfully imaged on industrial-quality films.

  19. Spaceborne weather radar

    NASA Technical Reports Server (NTRS)

    Meneghini, Robert; Kozu, Toshiaki

    1990-01-01

    The present work on the development status of spaceborne weather radar systems and services discusses radar instrument complementarities, the current forms of equations for the characterization of such aspects of weather radar performance as surface and mirror-image returns, polarimetry, and Doppler considerations, and such essential factors in spaceborne weather radar design as frequency selection, scanning modes, and the application of SAR to rain detection. Attention is then given to radar signal absorption by the various atmospheric gases, rain drop size distribution and wind velocity determinations, and the characteristics of clouds, as well as the range of available estimation methods for backscattering, single- and dual-wavelength attenuation, and polarimetric and climatological characteristics.

  20. Planetary Space Weather

    NASA Astrophysics Data System (ADS)

    Grande, M.

    2012-04-01

    Invited Talk - Space weather at other planets While discussion of space weather effects has so far largely been confined to the near-Earth environment, there are significant present and future applications to the locations beyond, and to other planets. Most obviously, perhaps, are the radiation hazards experienced by astronauts on the way to, and on the surface of, the Moon and Mars. Indeed, the environment experienced by planetary spacecraft in transit and at their destinations is of course critical to their design and successful operation. The case of forthcoming missions to Jupiter and Europa is an exreme example. Moreover, such craft can provide information which in turn increases our understanding of geospace. Indeed, space weather may be a significant factor in the habitability of other solar system and extrasolar planets, and the ability of life to travel between them.

  1. LINEAR ACCELERATOR

    DOEpatents

    Colgate, S.A.

    1958-05-27

    An improvement is presented in linear accelerators for charged particles with respect to the stable focusing of the particle beam. The improvement consists of providing a radial electric field transverse to the accelerating electric fields and angularly introducing the beam of particles in the field. The results of the foregoing is to achieve a beam which spirals about the axis of the acceleration path. The combination of the electric fields and angular motion of the particles cooperate to provide a stable and focused particle beam.

  2. Space Weather Workshop

    NASA Technical Reports Server (NTRS)

    Gallagher, D. L.

    2004-01-01

    This workshop will focus on what space weather is about and its impact on society. An overall picture will be "painted" describing the Sun's influence through the solar wind on the near-Earth space environment, including the aurora, killer electrons at geosynchronous orbit, million ampere electric currents through the ionosphere and along magnetic field lines, and the generation of giga-Watts of natural radio waves. Reference material in the form of Internet sites will be provided so that teachers can discuss space weather in the classroom and enable students to learn more about this topic.

  3. Study on the influence of the decoking agent on the activity of limestone in wet flue gas desulfurization

    NASA Astrophysics Data System (ADS)

    Li, Qianjun; Xu, Dongyang; Wu, Yunxia; Yu, Jin

    2017-01-01

    Influence of the main components of decoking agent (magnesium nitrate, aluminum nitrate, copper nitrate, ammonium nitrate and actual decoking agent) on the activity of limestone is studied in laboratory by MET method. Results show that magnesium nitrate, ammonium nitrate and copper nitrate almost has no effect on the activity of limestone. With the concentration increasing, aluminum nitrate has an increasing inhibition on the dissolution of limestone. Fly ash has inhibition on dissolution of limestone due to the blockage of limestone pore by fly ash. The actual decoking agent has almost no effect on the limestone.

  4. Oxalate secretion by ectomycorrhizal Paxillus involutus is mineral-specific and controls calcium weathering from minerals

    PubMed Central

    Schmalenberger, A.; Duran, A. L.; Bray, A. W.; Bridge, J.; Bonneville, S.; Benning, L. G.; Romero-Gonzalez, M. E.; Leake, J. R.; Banwart, S. A.

    2015-01-01

    Trees and their associated rhizosphere organisms play a major role in mineral weathering driving calcium fluxes from the continents to the oceans that ultimately control long-term atmospheric CO2 and climate through the geochemical carbon cycle. Photosynthate allocation to tree roots and their mycorrhizal fungi is hypothesized to fuel the active secretion of protons and organic chelators that enhance calcium dissolution at fungal-mineral interfaces. This was tested using 14CO2 supplied to shoots of Pinus sylvestris ectomycorrhizal with the widespread fungus Paxillus involutus in monoxenic microcosms, revealing preferential allocation by the fungus of plant photoassimilate to weather grains of limestone and silicates each with a combined calcium and magnesium content of over 10 wt.%. Hyphae had acidic surfaces and linear accumulation of weathered calcium with secreted oxalate, increasing significantly in sequence: quartz, granite < basalt, olivine, limestone < gabbro. These findings confirmed the role of mineral-specific oxalate exudation in ectomycorrhizal weathering to dissolve calcium bearing minerals, thus contributing to the geochemical carbon cycle. PMID:26197714

  5. Oxalate secretion by ectomycorrhizal Paxillus involutus is mineral-specific and controls calcium weathering from minerals.

    PubMed

    Schmalenberger, A; Duran, A L; Bray, A W; Bridge, J; Bonneville, S; Benning, L G; Romero-Gonzalez, M E; Leake, J R; Banwart, S A

    2015-07-22

    Trees and their associated rhizosphere organisms play a major role in mineral weathering driving calcium fluxes from the continents to the oceans that ultimately control long-term atmospheric CO2 and climate through the geochemical carbon cycle. Photosynthate allocation to tree roots and their mycorrhizal fungi is hypothesized to fuel the active secretion of protons and organic chelators that enhance calcium dissolution at fungal-mineral interfaces. This was tested using (14)CO2 supplied to shoots of Pinus sylvestris ectomycorrhizal with the widespread fungus Paxillus involutus in monoxenic microcosms, revealing preferential allocation by the fungus of plant photoassimilate to weather grains of limestone and silicates each with a combined calcium and magnesium content of over 10 wt.%. Hyphae had acidic surfaces and linear accumulation of weathered calcium with secreted oxalate, increasing significantly in sequence: quartz, granite < basalt, olivine, limestone < gabbro. These findings confirmed the role of mineral-specific oxalate exudation in ectomycorrhizal weathering to dissolve calcium bearing minerals, thus contributing to the geochemical carbon cycle.

  6. Oxalate secretion by ectomycorrhizal Paxillus involutus is mineral-specific and controls calcium weathering from minerals

    NASA Astrophysics Data System (ADS)

    Schmalenberger, A.; Duran, A. L.; Bray, A. W.; Bridge, J.; Bonneville, S.; Benning, L. G.; Romero-Gonzalez, M. E.; Leake, J. R.; Banwart, S. A.

    2015-07-01

    Trees and their associated rhizosphere organisms play a major role in mineral weathering driving calcium fluxes from the continents to the oceans that ultimately control long-term atmospheric CO2 and climate through the geochemical carbon cycle. Photosynthate allocation to tree roots and their mycorrhizal fungi is hypothesized to fuel the active secretion of protons and organic chelators that enhance calcium dissolution at fungal-mineral interfaces. This was tested using 14CO2 supplied to shoots of Pinus sylvestris ectomycorrhizal with the widespread fungus Paxillus involutus in monoxenic microcosms, revealing preferential allocation by the fungus of plant photoassimilate to weather grains of limestone and silicates each with a combined calcium and magnesium content of over 10 wt.%. Hyphae had acidic surfaces and linear accumulation of weathered calcium with secreted oxalate, increasing significantly in sequence: quartz, granite < basalt, olivine, limestone < gabbro. These findings confirmed the role of mineral-specific oxalate exudation in ectomycorrhizal weathering to dissolve calcium bearing minerals, thus contributing to the geochemical carbon cycle.

  7. Crystallographic transformation of limestone during calcination under CO2.

    PubMed

    Valverde, Jose Manuel; Medina, Santiago

    2015-09-14

    The calcination reaction of limestone (CaCO3) to yield lime (CaO) is at the heart of many industrial applications as well as natural processes. In the recently emerged calcium-looping technology, CO2 capture is accomplished by the carbonation of CaO in a gas-solid reactor (carbonator). CaO is derived by the calcination of limestone in a calciner reactor under necessarily high CO2 partial pressure and high temperature. In situ X-ray diffraction (XRD) has been employed in this work to gain further insight into the crystallographic transformation that takes place during the calcination of limestone under CO2, at partial pressures (P) close to the equilibrium pressure (Peq) and at high temperature. Calcination under these conditions becomes extremely slow. The in situ XRD analysis presented here suggests the presence of an intermediate metastable CaO* phase stemming from the parent CaCO3 structure. According to the reaction mechanism proposed elsewhere, the exothermicity of the CaO* → CaO transformation and high values of P/Peq inhibit the nucleation of CaO at high temperatures. The wt% of CaO* remains at a relatively high level during slow calcination. Two diverse stages have been identified in the evolution of CaO crystallite size, L. Initially, L increases with CaCO3 conversion, following a logarithmic law. Slow calcination allows the crystallite size to grow up from a few nanometers at nucleation up to around 100 nm near the end of conversion. Otherwise, quick calcination at relatively lower CO2 concentrations limits CaO crystallite growth. Once calcination reaches an advanced state, the presence of CaO* drops to zero and the rate of increase of the CaO crystallite size is significantly hindered. Arguably, the first stage in CaO crystallite growth is driven by aggregation of the metastable CaO* nanocrystals, due to surface attractive forces, whereas the second one is consistent with sintering of the aggregated CaO crystals, and persists with time after full

  8. NASA Aviation Safety Program Weather Accident Prevention/Weather Information Communications (WINCOMM)

    NASA Astrophysics Data System (ADS)

    Feinberg, Arthur; Tauss, James

    2002-10-01

    Weather is a contributing factor in approximately 25-30 percent of general aviation accidents. The lack of timely, accurate and usable weather information to the general aviation pilot in the cockpit to enhance pilot situational awareness and improve pilot judgment remains a major impediment to improving aviation safety. NASA Glenn Research Center commissioned this 120 day weather datalink market survey to assess the technologies, infrastructure, products, and services of commercial avionics systems being marketed to the general aviation community to address these longstanding safety concerns. A market survey of companies providing or proposing to provide graphical weather information to the general aviation cockpit was conducted. Fifteen commercial companies were surveyed. These systems are characterized and evaluated in this report by availability, end-user pricing/cost, system constraints/limits and technical specifications. An analysis of market survey results and an evaluation of product offerings were made. In addition, recommendations to NASA for additional research and technology development investment have been made as a result of this survey to accelerate deployment of cockpit weather information systems for enhancing aviation safety.

  9. NASA Aviation Safety Program Weather Accident Prevention/weather Information Communications (WINCOMM)

    NASA Technical Reports Server (NTRS)

    Feinberg, Arthur; Tauss, James; Chomos, Gerald (Technical Monitor)

    2002-01-01

    Weather is a contributing factor in approximately 25-30 percent of general aviation accidents. The lack of timely, accurate and usable weather information to the general aviation pilot in the cockpit to enhance pilot situational awareness and improve pilot judgment remains a major impediment to improving aviation safety. NASA Glenn Research Center commissioned this 120 day weather datalink market survey to assess the technologies, infrastructure, products, and services of commercial avionics systems being marketed to the general aviation community to address these longstanding safety concerns. A market survey of companies providing or proposing to provide graphical weather information to the general aviation cockpit was conducted. Fifteen commercial companies were surveyed. These systems are characterized and evaluated in this report by availability, end-user pricing/cost, system constraints/limits and technical specifications. An analysis of market survey results and an evaluation of product offerings were made. In addition, recommendations to NASA for additional research and technology development investment have been made as a result of this survey to accelerate deployment of cockpit weather information systems for enhancing aviation safety.

  10. Acceleration switch

    DOEpatents

    Abbin, Jr., Joseph P.; Devaney, Howard F.; Hake, Lewis W.

    1982-08-17

    The disclosure relates to an improved integrating acceleration switch of the type having a mass suspended within a fluid filled chamber, with the motion of the mass initially opposed by a spring and subsequently not so opposed.

  11. Acceleration switch

    DOEpatents

    Abbin, J.P. Jr.; Devaney, H.F.; Hake, L.W.

    1979-08-29

    The disclosure relates to an improved integrating acceleration switch of the type having a mass suspended within a fluid filled chamber, with the motion of the mass initially opposed by a spring and subsequently not so opposed.

  12. ION ACCELERATOR

    DOEpatents

    Bell, J.S.

    1959-09-15

    An arrangement for the drift tubes in a linear accelerator is described whereby each drift tube acts to shield the particles from the influence of the accelerating field and focuses the particles passing through the tube. In one embodiment the drift tube is splii longitudinally into quadrants supported along the axis of the accelerator by webs from a yoke, the quadrants. webs, and yoke being of magnetic material. A magnetic focusing action is produced by energizing a winding on each web to set up a magnetic field between adjacent quadrants. In the other embodiment the quadrants are electrically insulated from each other and have opposite polarity voltages on adjacent quadrants to provide an electric focusing fleld for the particles, with the quadrants spaced sufficienily close enough to shield the particles within the tube from the accelerating electric field.

  13. LINEAR ACCELERATOR

    DOEpatents

    Christofilos, N.C.; Polk, I.J.

    1959-02-17

    Improvements in linear particle accelerators are described. A drift tube system for a linear ion accelerator reduces gap capacity between adjacent drift tube ends. This is accomplished by reducing the ratio of the diameter of the drift tube to the diameter of the resonant cavity. Concentration of magnetic field intensity at the longitudinal midpoint of the external sunface of each drift tube is reduced by increasing the external drift tube diameter at the longitudinal center region.

  14. Identification of Calcium Sulphoaluminate Formation between Alunite and Limestone

    PubMed Central

    Kim, Hyung-Seok; Han, Gi-Chun; Ahn, Ji-Whan; Cho, Kye-Hong; Cho, Hee-Chan

    2009-01-01

    This study was carried out to identify the conditions of formation of calcium sulphoaluminate (3CaO·3Al2O3·CaSO4) by the sintering of a limestone (CaCO3) and alunite [K2SO4·Al2(SO4)3·4Al(OH)3] mixture with the following reagents: K2SO4, CaCO3, Al(OH)3, CaSO4·2H2O, and SiO2. When K2SO4, CaCO3, Al(OH)3, CaSO4·2H2O were mixed in molar ratios of 1:3:6:3 and sintered at 1,200∼1,300 °C, only 3CaO·3Al2O3·CaSO4 and calcium langbeinite (2CaSO4·K2SO4) were generated. With an amount of CaO that is less than the stoichiometric molar ratio, 3CaO·3Al2O3·CaSO4 was formed and anhydrite (CaSO4) did not react and remained behind. With the amount of CaSO4 that is less than the stoichiometric molar ratio, the amounts of 3CaO·3Al2O3·CaSO4 and 2CaSO4·K2SO4 decreased, and that of CaO·Al2O3 increased. In the K2SO4-CaO-Al2O3-CaSO4-SiO2 system, to stabilize the formation of 3CaO·3Al2O3·CaSO4, 2CaSO4·K2SO4, and β-2CaO·SiO2, the molar ratios of CaO: Al2O3: CaSO4 must be kept at 3:3:1 and that of CaO/SiO2, over 2.0; otherwise, the generated amount of 3CaO·3Al2O3·CaSO4 decreased and that of gehlenite (2CaO·Al2O3·SiO2) with no hydration increased quantitatively. Therefore, if all SO3(g) generated by the thermal decomposition of alunite reacts with CaCO3 (or CaO, the thermal decomposition product of limestone) to form CaSO4 in an alunite- limestone system, 1 mol of pure alunite reacts with 6 mol of limestone to form 1 mol of 3CaO·3Al2O3·CaSO4 and 1 mol of 2CaSO4·K2SO4. PMID:22346687

  15. SLAM: a sodium-limestone concrete ablation model

    SciTech Connect

    Suo-Anttila, A.J.

    1983-12-01

    SLAM is a three-region model, containing a pool (sodium and reaction debris) region, a dry (boundary layer and dehydrated concrete) region, and a wet (hydrated concrete) region. The model includes a solution to the mass, momentum, and energy equations in each region. A chemical kinetics model is included to provide heat sources due to chemical reactions between the sodium and the concrete. Both isolated model as well as integrated whole code evaluations have been made with good results. The chemical kinetics and water migration models were evaluated separately, with good results. Several small and large-scale sodium limestone concrete experiments were simulated with reasonable agreement between SLAM and the experimental results. The SLAM code was applied to investigate the effects of mixing, pool temperature, pool depth and fluidization. All these phenomena were found to be of significance in the predicted response of the sodium concrete interaction. Pool fluidization is predicted to be the most important variable in large scale interactions.

  16. Producing Portland cement from iron and steel slags and limestone

    SciTech Connect

    Monshi, A.; Asgarani, M.K.

    1999-09-01

    The slags from blast furnace (iron making) and converter (steel making) after magnetic separation are mixed with limestone of six different compositions. The ground materials are fired in a pilot plant scale rotary kiln to 1,350 C for 1 h. The clinker is cooled, crushed, mixed with 3% gypsum, and ground to fineness of more than 3,300 cm{sub 2}/g. Initial and final setting times, consistency of standard paste, soundness, free CaO, and compressive and fractural strengths after 3, 7, and 28 days are measured. Samples with higher lime saturation factor developed higher C{sub 3}S content and better mechanical properties. Blending 10% extra iron slag to a cement composed of 49% iron slag, 43% calcined lime, and 8% steel slag kept the compressive strength of concrete above standard values for type I ordinary Portland cement.

  17. OPTIMIZATION OF A PULSED LIMESTONE BED REACTOR AT THE ARGO TUNNEL IN IDAHO SPRINGS, COLORADO

    EPA Science Inventory

    Acid Mine Drainage (AMD) is an unintended consequence of coal and metal mining that adversely affects thousands of miles of streams both in the eastern and western regions of the U.S. A novel AMD treatment process based on limestone based on limestone neutralization has been dev...

  18. Adsorption and desorption of phosphate on limestone in experiments simulating seawater intrusion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The absorption and desorption of phosphorus on a large block of limestone was investigated using deionized water (DIW) and seawater. The limestone had a high affinity to adsorb phosphorus in DIW. Phosphate adsorption was significantly less in seawater, and more phosphorus was desorbed in the seawate...

  19. 76 FR 35396 - Black Hills National Forest, Mystic Ranger District, South Dakota, Section 30 Limestone Mining...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-17

    ... Mining Project AGENCY: Forest Service, USDA. ACTION: Corrected Notice of intent to prepare an... the purpose of mining for chemical grade limestone within mining claims on National Forest System land... publication dates. A Notice of Availability for the Section 30 Limestone Mining Project Draft EIS...

  20. STEAM ENHANCED REMEDIATION RESEARCH FOR DNAPL IN FRACTURED ROCK, LORING AIR FORCE BASE, LIMESTONE, MAINE

    EPA Science Inventory

    This report details a research project on Steam Enhanced Remediation (SER) for the recovery of volatile organic compounds from fractured limestone that was carried out at the Quarry at the former Loring Air Force Base in Limestone, Maine. This project was carried out by USEPA, Ma...

  1. Weathering the Double Whammy.

    ERIC Educational Resources Information Center

    Wellman, Jane V.

    2002-01-01

    Discusses how governing boards can help their institutions weather the "double-whammy" of doing more with less: identify the institution's short-term and long-term challenges; refocus the institution's mission, planning, and programming; assess and integrate the institution's tuition, aid, and outreach strategies; redouble the…

  2. Weather Specialist (AFSC 25120).

    ERIC Educational Resources Information Center

    Air Univ., Gunter AFS, Ala. Extension Course Inst.

    This correspondence course is designed for self-study to help military personnel to attain the rating of weather specialist. The course is organized in three volumes. The first volume, containing seven chapters, covers background knowledge, meteorology, and climatology. In the second volume, which also contains seven chapters, surface…

  3. Microbial Weathering of Olivine

    NASA Technical Reports Server (NTRS)

    McKay, D. S.; Longazo, T. G.; Wentworth, S. J.; Southam, G.

    2002-01-01

    Controlled microbial weathering of olivine experiments displays a unique style of nanoetching caused by biofilm attachment to mineral surfaces. We are investigating whether the morphology of biotic nanoetching can be used as a biosignature. Additional information is contained in the original extended abstract.

  4. Weather and Flight Testing

    NASA Technical Reports Server (NTRS)

    Wiley, Scott

    2007-01-01

    This viewgraph document reviews some of the weather hazards involved with flight testing. Some of the hazards reviewed are: turbulence, icing, thunderstorms and winds and windshear. Maps, pictures, satellite pictures of the meteorological phenomena and graphs are included. Also included are pictures of damaged aircraft.

  5. Worldwide Marine Weather Broadcasts.

    ERIC Educational Resources Information Center

    Department of the Navy, Washington, DC.

    This publication is a source of marine weather broadcast information in all areas of the world where such service is provided. This publication was designed for the use of U.S. naval and merchant ships. Sections 1 through 4 contain details of radio telegraph, radio telephone, radio facsimile, and radio teleprinter transmissions, respectively. The…

  6. Weather at LANL

    SciTech Connect

    Bruggeman, David Alan

    2016-04-19

    This report gives general information about how to become a meteorologist and what kinds of jobs exist in that field. Then it goes into detail about why weather is monitored at LANL, how it is done, and where the data can be accessed online.

  7. Weather, Climate, and You.

    ERIC Educational Resources Information Center

    Blai, Boris, Jr.

    Information from the American Institute of Medical Climatologists on human responses to weather and climatic conditions, including clouds, winds, humidity, barometric pressure, heat, cold, and other variables that may exert a pervasive impact on health, behavior, disposition, and the level of efficiency with which individuals function is reviewed.…

  8. Dress for the Weather

    ERIC Educational Resources Information Center

    Glen, Nicole J.; Smetana, Lara K.

    2010-01-01

    "If someone were traveling to our area for the first time during this time of year, what would you tell them to bring to wear? Why?" This question was used to engage students in a guided-inquiry unit about how climate differs from weather. In this lesson, students explored local and national data sets to give "travelers" advice…

  9. Shipboard Weather Observation.

    ERIC Educational Resources Information Center

    Palmaccio, Richard J.

    1983-01-01

    Details of how observers on a moving ship can furnish an accurate report of wind velocity are provided. A method employing vector addition and some trigonometry is covered. Wind velocity is initially indicated through an anemometer and a wind vane. Ships are urged to radio weather data. (MP)

  10. Rainy Weather Science.

    ERIC Educational Resources Information Center

    Reynolds, Karen

    1996-01-01

    Presents ideas on the use of rainy weather for activities in the earth, life, and physical sciences. Topics include formation and collision of raindrops, amount and distribution of rain, shedding of water by plants, mapping puddles and potholes, rainbow formation, stalking storms online, lightning, and comparing particles in the air before and…

  11. Weather in Motion.

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Washington, DC.

    The ATS-111 weather satellite, launched on November 18, 1967, in a synchronous earth orbit 22,000 miles above the equator, is described in this folder. The description is divided into these topics: the satellite, the camera, the display, the picture information, and the beneficial use of the satellite. Photographs from the satellite are included.…

  12. Satellite Weather Watch.

    ERIC Educational Resources Information Center

    Summers, R. Joe

    1982-01-01

    Describes an inexpensive (about $1,500) direct-readout ground station for use in secondary school science/mathematics programs. Includes suggested activities including, among others, developing map overlays, operating station equipment, interpreting satellite data, developing weather forecasts, and using microcomputers for data storage, orbit…

  13. Dissolution-induced preferential flow in a limestone fracture.

    PubMed

    Liu, Jishan; Polak, Amir; Elsworth, Derek; Grader, Avrami

    2005-06-01

    Flow in a rock fracture is surprisingly sensitive to the evolution of flow paths that develop as a result of dissolution. Net dissolution may either increase or decrease permeability uniformly within the fracture, or may form a preferential flow path through which most of the injected fluid flows, depending on the prevailing ambient mechanical and chemical conditions. A flow-through test was completed on an artificial fracture in limestone at room temperature under ambient confining stress of 3.5 MPa. The sample was sequentially circulated by water of two different compositions through the 1500 h duration of the experiment; the first 935 h by tap groundwater, followed by 555 h of distilled water. Measurements of differential pressures between the inlet and the outlet, fluid and dissolved mass fluxes, and concurrent X-ray CT imaging and sectioning were used to characterize the evolution of flow paths within the limestone fracture. During the initial circulation of groundwater, the differential pressure increased almost threefold, and was interpreted as a net reduction in permeability as the contacting asperities across the fracture are removed, and the fracture closes. With the circulation of distilled water, permeability initially reduces threefold, and ultimately increases by two orders of magnitude. This spontaneous switch from net decrease in permeability, to net increase occurred with no change in flow rate or applied effective stress, and is attributed to the evolving localization of flow path as evidenced by CT images. Based on the X-ray CT characterizations, a flow path-dependent flow model was developed to simulate the evolution of flow paths within the fracture and its influence on the overall flow behaviors of the injected fluid in the fracture.

  14. Thermal strengthening of limestone: monument preservation during fire

    NASA Astrophysics Data System (ADS)

    Heap, Michael; Lavallee, Yan; Benson, Philip; Hess, Kai-Uwe; Dingwell, Donald

    2010-05-01

    The use of natural rocks in the construction of buildings and monuments predates the use of commercially engineered materials such as concrete. Such building material can be subject to elevated temperatures in the misfortunate event of a fire. In civil engineering, it is generally appreciated that the strength of rock is decreased when it is or has been exposed to elevated temperatures. This is due the formation of thermal microcracks, a result of the thermal expansion mismatch between different minerals in the rock. Even today, fire is by no means an uncommon occurrence and approximately one historic building is lost to fire in the European Union every day (COST C17 2001). A large number of historically significant buildings and monuments are constructed from carbonate material. However, could the paradigm of thermal weakening of limestone construction material be in part, a paradox? We report new findings on the thermal strengthening of the Solnhofen limestone (Solnhofen, Germany), a carbonate rock traditionally used in construction of building and statues in central Europe. Two types of deformation experiments were performed to investigate: (1) the strength of samples at elevated temperatures (i.e. during fire) and (2) the strength of samples at room temperature after heat-treatment (i.e. after fire). During experimentation, microcracking was monitored by the output of acoustic emissions (AE). Thermo-gravimetric (TG) analysis was also undertaken to measure the mass loss during heating. For the experiments ‘during fire', samples were heated to temperatures of 25°, 200°, 400°, 500°, 600°, 650° and 800°C at a controlled rate of 5°C/min and deformed until failure in a uniaxial press at a constant strain rate of 10-5 s-1. For the experiments ‘after fire', samples were heat-treated to each 100°C increment up to 800°C, they were then cooled at the same rate and their strength tested at room temperature. The mechanical data demonstrate that, during fire

  15. Weatherization Works: An interim report of the National Weatherization Evaluation

    SciTech Connect

    Brown, M.A.; Berry, L.G.; Kinney, L.F.

    1993-11-01

    The National Weatherization Evaluation is the first comprehensive evaluation of the Weatherization Assistance Program since 1984. The evaluation was designed to accomplish the following goals: Estimate energy savings and cost effectiveness; Assess nonenergy impacts; Describe the weatherization network; Characterize the eligible population and resources; and Identify factors influencing outcomes and opportunities for the future. As a national program, weatherization incorporates considerable diversity due to regional differences. Therefore, evaluation results are presented both in aggregate and for three climate regions: cold, moderate and hot.

  16. Toxicity of acid mine pit lake water remediated with limestone and phosphorus.

    PubMed

    Neil, Luke L; McCullough, Clint D; Lund, Mark A; Evans, Louis H; Tsvetnenko, Yuri

    2009-11-01

    Pit lakes are increasingly common worldwide and have potential to provide many benefits. However, lake water toxicity may require remediation before beneficial end uses can be realised. Three treatments to remediate AMD (pH approximately 4.8) pit lake water containing elevated concentrations of Al and Zn from Collie, Western Australia were tested in mesocosms. Treatments were: (a) limestone neutralisation (L), (b) phosphorus amendment (P), and (c) combined limestone neutralisation and phosphorus amendment (L+P). Laboratory bioassays with Ceriodaphnia cf. dubia, Chlorella protothecoides and Tetrahymena thermophila assessed remediation. Limestone neutralisation increased pH and reduced heavy metal concentrations by 98% (Al) to 14% (Mg), removing toxicity to the three test species within 2 months. Phosphorus amendment removed toxicity after 6 months of treatment. However, phosphorus amendment to prior limestone neutralisation failed to reduce toxicity more than limestone neutralisation alone. Low concentrations of both phosphorus and nitrogen appear to limit phytoplankton population growth in all treatments.

  17. Toxicity of acid mine pit lake water remediated with limestone and phosphorus

    SciTech Connect

    Neil, L.L.; McCullough, C.D.; Lund, M.A.; Evans, L.H.; Tsvetnenko, Y.

    2009-11-15

    Pit lakes are increasingly common worldwide and have potential to provide many benefits. However, lake water toxicity may require remediation before beneficial end uses can be realised. Three treatments to remediate AMD (pH similar to 4.8) pit lake water containing elevated concentrations of Al and Zn from Collie, Western Australia were tested in mesocosms. Treatments were: (a) limestone neutralisation (L), (b) phosphorus amendment (P), and c) combined limestone neutralisation and phosphorus amendment (L+P). Laboratory bioassays with Ceriodaphnia cf. dubia, Chlorella protothecoides and Tetrahymena thermophila assessed remediation. Limestone neutralisation increased pH and reduced heavy metal concentrations by 98% (Al) to 14% (Mg), removing toxicity to the three test species within 2 months. Phosphorus amendment removed toxicity after 6 months of treatment. However, phosphorus amendment to prior limestone neutralisation failed to reduce toxicity more than limestone neutralisation alone. Low concentrations of both phosphorus and nitrogen appear to limit phytoplankton population growth in all treatments.

  18. Dissolution rate of limestone for wet flue gas desulfurization in the presence of sulfite.

    PubMed

    Xiang, Gao; Rui-tang, Guo; Hong-lei, Ding; Zhong-yang, Luo; Ke-fa, Cen

    2009-09-15

    Limestone dissolution rate was measured by a pH-stat method with CO(2) sparging and dissolved sulfite. The dissolution rate of limestone under these conditions was found to be controlled by mass transfer and surface kinetics. As can be seen from the results, in the presence of sulfite, limestone dissolution rate increases with increasing stirring speed, reaction temperature and CO(2) partial pressure. The crystallinity of limestone has a great impact on the dissolution rate: The lower the value of the crystallinity of limestone is, the higher the dissolution rate is. The presence of sulfite promotes the dissolution rate when pH value is below 5.5 but inhibits it when pH value is above 5.5.

  19. FMC limestone double-alkali flue gas desulfurization process: Pilot plant testing: Final report

    SciTech Connect

    Troupe, J.S.; Shepley, D.C.

    1987-07-01

    This report documents pilot plant testing of a 3 MW (9500 acfm equivalent flue gas flow) FMC limestone double alkali FGD process operating on a slipstream of a commercial 420 MW boiler burning 3.5% sulfur coal. The report discusses the rationale behind EPRI's decision to participate in the testing aspects of this project, the history of the development of limestone double alkali technology, and the chemistry involved in this technology's operation. The largest part of the report is devoted to the results obtained from tests conducted during 65 days of pilot plant operation. All of the major raw and reduced operating and analytical data taken during testing are reproduced in the appendices to the report, along with quality assurance information to support the validity of the data obtained. The report discusses the test results in detail and presents technical observations regarding their implications. The FMC limestone double alkali FGD process (1) can consistently remove 92 to 93% of SO/sub 2/ from high-sulfur coal flue gas, (2) can achieve high limestone utilization and low soda ash losses, (3) produces a manageable waste filter cake, (4) is highly tolerant of upsets in limestone feed, soda ash makeup, and regeneration residence time, and (5) presents no unusual safety or environmental problems. The process, like conventional limestone scrubbing, shows some adverse effects of increasing soluble magnesium concentration on solids quality and requires a finely ground limestone feed material to achieve high limestone utilization. However, neither limestone grind nor magnesium concentration appears to affect SO/sub 2/ removal efficiency. The report suggests specific lines of future developmental work and future demonstration testing to enhance the attractiveness of this process to the electric utility industry. A bibliography of limestone double alkali literature is included. 3 refs., 25 figs., 4 tabs.

  20. Bringing Weather into Your Classroom.

    ERIC Educational Resources Information Center

    Mogil, H. Michael

    1979-01-01

    Discusses meteorological resources available to classroom teachers. Describes in detail the National Oceanic and Atmospheric Administration (NOAA) Weather Radio and the A.M. Weather Show on Public Broadcasting Service (PBS). Includes addresses where teachers can get more information. (MA)

  1. Geography and Weather: Mountain Meterology.

    ERIC Educational Resources Information Center

    Mogil, H. Michael; Collins, H. Thomas

    1990-01-01

    Provided are 26 ideas to help children explore the effects of mountains on the weather. Weather conditions in Nepal and Colorado are considered separately. Nine additional sources of information are listed. (CW)

  2. Origin and Evolution of Limestone Caves of Chhattisgarh and Orissa, India: Role of Geomorphic, Tectonic and Hydrological Processes

    NASA Astrophysics Data System (ADS)

    Gautam, P. K.; Allu, N. C.; Ramesh, R.; Yadava, M. G.; Panigrahi, C. P.

    2014-12-01

    Carbonate rocks undergo karstic process and karst morphology is a key to understand the nature and genesis of caves. The primary energy source for the formation of karst landforms is hydrological cycle. Geomorphic features along with hydrological characteristics provide important information not only on karst formation but also climate and environmental conditions. In this paper, we present the tectonic and geomorphic features that played a role in evolution of caves located in Chhattisgarh and Orissa States of India. The geomorphic and tectonic aspects of Kotumsar, Kailash, and Gupteshwar caves are discussed in relation to the origin and evolution of these caves. Caves are located near the water falls. The area is folded and faulted along the Eastern Ghat Mobile Belt (EGMB) due to tectonic reactivation. Shaly-limestone beds exhibit vertical dipping near Gupteshwar cave, and steeply inclined near Kotumsar and Kailash caves. Indrāvati and Sabari/Kolab tributaries of the Godavari River drain the area. The landscape evolution and the origin of caves in the region is a multistage process, where the lithology, orogeny, fluvial action, and monsoon are the main agents, which is similar to the four state model (Ford and Ewers, 1978). The river basin evolution and regional tectonism also caused the initiation of karstification in the region. The evolution of caves is believed to have taken place in Pre-Pliocene under more humid conditions that coincided with the initiation of monsoon in India. Further, during the Quaternary wet-dry/cold-warm phases altered physical and chemical weathering of limestone rocks. Contrasting relief features of Bastar plateau have also helped the extensive cave formation in the region. The dissolution along weak planes initiated the openings of caves, further enlarged by geomorphic agents. Both monsoon and tectonics have caused fluctuations in water levels along river courses, which acted as active agents in evolution of caves.

  3. Space Weather: The Solar Perspective

    NASA Astrophysics Data System (ADS)

    Schwenn, Rainer

    2006-12-01

    The term space weather refers to conditions on the Sun and in the solar wind, magnetosphere, ionosphere, and thermosphere that can influence the performance and reliability of space-borne and ground-based technological systems and that can affect human life and health. Our modern hi-tech society has become increasingly vulnerable to disturbances from outside the Earth system, in particular to those initiated by explosive events on the Sun: Flares release flashes of radiation that can heat up the terrestrial atmosphere such that satellites are slowed down and drop into lower orbits, solar energetic particles accelerated to near-relativistic energies may endanger astronauts traveling through interplanetary space, and coronal mass ejections are gigantic clouds of ionized gas ejected into interplanetary space that after a few hours or days may hit the Earth and cause geomagnetic storms. In this review, I describe the several chains of actions originating in our parent star, the Sun, that affect Earth, with particular attention to the solar phenomena and the subsequent effects in interplanetary space.

  4. Weathering of Roofing Materials-An Overview

    SciTech Connect

    Berdahl, Paul; Akbari, Hashem; Levinson, Ronnen; Miller, William A.

    2006-03-30

    An overview of several aspects of the weathering of roofing materials is presented. Degradation of materials initiated by ultraviolet radiation is discussed for plastics used in roofing, as well as wood and asphalt. Elevated temperatures accelerate many deleterious chemical reactions and hasten diffusion of material components. Effects of moisture include decay of wood, acceleration of corrosion of metals, staining of clay, and freeze-thaw damage. Soiling of roofing materials causes objectionable stains and reduces the solar reflectance of reflective materials. (Soiling of non-reflective materials can also increase solar reflectance.) Soiling can be attributed to biological growth (e.g., cyanobacteria, fungi, algae), deposits of organic and mineral particles, and to the accumulation of flyash, hydrocarbons and soot from combustion.

  5. Weather Folklore: Fact or Fiction?

    ERIC Educational Resources Information Center

    Jones, Gail; Carter, Glenda

    1995-01-01

    Integrating children's weather-related family folklore with scientific investigation can be an effective way to involve elementary and middle level students in lessons spanning the disciplines of science, geography, history, anthropology, and language arts. Describes weather folklore studies and examples of weather investigations performed with…

  6. Weather Specialist/Aerographer's Mate.

    ERIC Educational Resources Information Center

    Chanute AFB Technical Training Center, IL.

    This course trains Air Force personnel to perform duties prescribed for weather specialists and aerographer's mates. Training includes meteorology, surface and ship observation, weather radar, operation of standard weather instruments and communications equipment, and decoding and plotting of surface and upper air codes upon standard maps and…

  7. Severe Weather Planning for Schools

    ERIC Educational Resources Information Center

    Watson, Barbara McNaught; Strong, Christopher; Bunting, Bill

    2008-01-01

    Flash floods, severe thunderstorms, and tornadoes occur with rapid onset and often no warning. Decisions must be made quickly and actions taken immediately. This paper provides tips for schools on: (1) Preparing for Severe Weather Emergencies; (2) Activating a Severe Weather Plan; (3) Severe Weather Plan Checklist; and (4) Periodic Drills and…

  8. Weather Fundamentals: Climate & Seasons. [Videotape].

    ERIC Educational Resources Information Center

    1998

    The videos in this educational series for grades 4-7, help students understand the science behind weather phenomena through dramatic live-action footage, vivid animated graphics, detailed weather maps, and hands-on experiments. This episode (23 minutes), describes weather patterns and cycles around the globe. The various types of climates around…

  9. Improved weather information and aviation

    NASA Technical Reports Server (NTRS)

    Hallahan, K.; Zdanys, V.

    1973-01-01

    The major impacts of weather forecasts on aviation are reviewed. Topics discussed include: (1) present and projected structure of American aviation, (2) weather problems considered particularly important for aviation, (3) projected needs for improved weather information by aviators, (4) safety and economics, and (5) future studies utilizing satellite meteorology.

  10. A new species of limestone karst inhabiting forest frog, genus Platymantis (Amphibia: Anura: Ceratobatrachidae: subgenus Lupacolus) from southern Luzon Island, Philippines.

    PubMed

    Brown, Rafe M; De Layola, Louise Abigail; Lorenzo, Antonio; Diesmos, Mae Lowe L; Diesmos, Arvin C

    2015-11-25

    We describe a new species of limestone karst dwelling forest frog of the genus Platymantis from the Quezon Protected Landscape in southeastern Luzon Island, Philippines. We assign Platymantis quezoni, sp. nov., to the diverse assemblage of terrestrial species in the Platymantis dorsalis Group, subgenus Lupacolus on the basis of its body size and proportions, only slightly expanded terminal discs of the fingers and toes, and its terrestrial microhabitat. The new species is distinguished from these and all other Philippine congeners by features of its external morphology, its restriction to a distinctive limestone karst microhabitat, and its advertisement call, which is unique among frogs of the family Ceratobatrachidae. Several distinguishing morphological characters include its moderate body size (22.1-33.9 mm SVL for 16 adult males and 32.4-39.7 mm SVL for five adult females), slightly expanded terminal discs of the fingers and toes, smooth skin with limited dermal tuberculation, and a dorsal color pattern of mottled tan to dark brown with black blotches. The new species is the sixth Philippine Platymantis known to occur exclusively on limestone karst substrates (previously known karst-obligate species include: P. bayani, P. biak, P. insulatus, P. paengi, and P. speleaus). Recently accelerated discovery of limestone karst anurans across the Philippines suggests that numerous additional species may await discovery on the hundreds of scattered karst formations throughout the archipelago. This possibility suggests that a major conservation priority in coming years will be to study, characterize, describe, and preserve the endemic species supported by this patchy, unique and imperiled type of forest ecosystem in the Philippines.

  11. Acceleration Studies

    NASA Technical Reports Server (NTRS)

    Rogers, Melissa J. B.

    1993-01-01

    Work to support the NASA MSFC Acceleration Characterization and Analysis Project (ACAP) was performed. Four tasks (analysis development, analysis research, analysis documentation, and acceleration analysis) were addressed by parallel projects. Work concentrated on preparation for and implementation of near real-time SAMS data analysis during the USMP-1 mission. User support documents and case specific software documentation and tutorials were developed. Information and results were presented to microgravity users. ACAP computer facilities need to be fully implemented and networked, data resources must be cataloged and accessible, future microgravity missions must be coordinated, and continued Orbiter characterization is necessary.

  12. CME front and severe space weather

    NASA Astrophysics Data System (ADS)

    Balan, N.; Skoug, R.; Tulasi Ram, S.; Rajesh, P. K.; Shiokawa, K.; Otsuka, Y.; Batista, I. S.; Ebihara, Y.; Nakamura, T.

    2014-12-01

    Thanks to the work of a number of scientists who made it known that severe space weather can cause extensive social and economic disruptions in the modern high-technology society. It is therefore important to understand what determines the severity of space weather and whether it can be predicted. We present results obtained from the analysis of coronal mass ejections (CMEs), solar energetic particle (SEP) events, interplanetary magnetic field (IMF), CME-magnetosphere coupling, and geomagnetic storms associated with the major space weather events since 1998 by combining data from the ACE and GOES satellites with geomagnetic parameters and the Carrington event of 1859, the Quebec event of 1989, and an event in 1958. The results seem to indicate that (1) it is the impulsive energy mainly due to the impulsive velocity and orientation of IMF Bz at the leading edge of the CMEs (or CME front) that determine the severity of space weather. (2) CMEs having high impulsive velocity (sudden nonfluctuating increase by over 275 km s-1 over the background) caused severe space weather (SvSW) in the heliosphere (failure of the solar wind ion mode of Solar Wind Electron Proton Alpha Monitor in ACE) probably by suddenly accelerating the high-energy particles in the SEPs ahead directly or through the shocks. (3) The impact of such CMEs which also show the IMF Bz southward from the leading edge caused SvSW at the Earth including extreme geomagnetic storms of mean DstMP < -250 nT during main phases, and the known electric power outages happened during some of these SvSW events. (4) The higher the impulsive velocity, the more severe the space weather, like faster weather fronts and tsunami fronts causing more severe damage through impulsive action. (5) The CMEs having IMF Bz northward at the leading edge do not seem to cause SvSW on Earth, although, later when the IMF Bz turns southward, they can lead to super geomagnetic storms of intensity (Dstmin) less than even -400 nT.

  13. Whether weather affects music

    NASA Astrophysics Data System (ADS)

    Aplin, Karen L.; Williams, Paul D.

    2012-09-01

    The creative output of composers, writers, and artists is often influenced by their surroundings. To give a literary example, it has been claimed recently that some of the characters in Oliver Twist and A Christmas Carol were based on real-life people who lived near Charles Dickens in London [Richardson, 2012]. Of course, an important part of what we see and hear is not only the people with whom we interact but also our geophysical surroundings. Of all the geophysical phenomena to influence us, the weather is arguably the most significant because we are exposed to it directly and daily. The weather was a great source of inspiration for artists Claude Monet, John Constable, and William Turner, who are known for their scientifically accurate paintings of the skies [e.g., Baker and Thornes, 2006].

  14. Thermospheric Space Weather Modeling

    DTIC Science & Technology

    2007-06-01

    atmospheric temperature V = satellite velocity relative to the ambient gas ’ Senior physicist, Space Weather Center of Excellence, Mail Stop: VSBXT; Member...where temperature rises drastically to -600 - 2000 K. The density and hence drag in this region is driven mainly by two solar influences: directly by EUV...bulge that drives winds to transport heat away from the hot dayside toward the Earth’s cold nightside. Temperatures on the dayside are typically 30

  15. Weather Radar Studies.

    DTIC Science & Technology

    2014-09-26

    and Doppler weather radar data from the National Center for Atmospheric Research JAWS program and the National .Severe Storms Laboratory, are being...Atmospheric Research JAWS program and the National Severe Storms Laboratory, are being analyzed to develop low-altitude wind-shear detection algorithms...pictures, and dusted for fingerprints. The wind sensors, rain gauge, and antenna were destroyed but the DCP, solar panel, and other site components

  16. Space Weather Ballooning

    NASA Astrophysics Data System (ADS)

    Phillips, Tony; Johnson, Sam; Koske-Phillips, Amelia; White, Michael; Yarborough, Amelia; Lamb, Aaron; Herbst, Anna; Molina, Ferris; Gilpin, Justin; Grah, Olivia; Perez, Ginger; Reid, Carson; Harvey, Joey; Schultz, Jamie

    2016-10-01

    We have developed a "Space Weather Buoy" for measuring upper atmospheric radiation from cosmic rays and solar storms. The Buoy, which is carried to the stratosphere by helium balloons, is relatively inexpensive and uses off-the-shelf technology accessible to small colleges and high schools. Using this device, we have measured two Forbush Decreases and a small surge in atmospheric radiation during the St. Patrick's Day geomagnetic storm of March 2015.

  17. Salt Weathering on Mars

    NASA Astrophysics Data System (ADS)

    Jagoutz, E.

    2006-12-01

    Large well rounded boulders and angular rock fragments characterizes the Martian landscape as seen on the recent excellent quality photos. Analyzing the different rock-shapes indicates a time sequence of emplacement, fragmentation and transport of different rocks on Mars, which might give interesting insight into transport and weathering processes. Larger commonly well rounded boulders were emplaced onto gravel plains. After emplacement, these rocks were fragmented and disassembled. Nests of angular rock fragments are marking the locations of preexisting larger rocks. Frequently it is possible to reconstruct larger rounded rocks from smaller angular fragments. In other cases transport after fragmentation obscured the relationship of the fragments. However, a strewn field of fragments is still reminiscent of the preexisting rock. Mechanical salt weathering could be a plausible explanation for the insitu fragmentation of larger rounded blocks into angular fragments. Impact or secondary air fall induced fragmentation produces very different patterns, as observed around impact crates on Earth. Salt weathering of rocks is a common process in terrestrial environments. Salt crystallization in capillaries causes fragmentation of rocks, irrespective of the process of salt transportation and concentration. On Earth significant salt weathering can be observed in different climatic environments: in the transition zone of alluvial aprons and salt playas in desserts and in dry valleys of Antarctica. In terrestrial semi-arid areas the salt is transported by salt solution, which is progressively concentrated by evaporation. In Antarctic dry valleys freeze-thaw cycles causes salt transportation and crystallization resulting in rock fragmentation. This salt induced process can lead to complete destruction of rocks and converts rocks to fine sand. The efficient breakdown of rocks is dominating the landscape in some dry valleys of the Earth but possibly also on Mars. (Malin, 1974

  18. Weather Radar Technology Development

    DTIC Science & Technology

    1990-08-15

    uelocitV WMs ) data processing systems such as NEXRAD to have a reliable technique for removing ambiguities due to velocity aliasing. Performance of many...intended for automated implementation on radar systems such as the NEXt generation weather RADar ( NEXRAD ) system. Several research areas were addressed...with Doppler radar will soon be realized with the deployment of the NEXRAD radar systems. Some of these large scale storms can have devastating wind

  19. Benign Weather Modification

    DTIC Science & Technology

    2007-11-02

    The first Combat Search and Rescue (CSAR) attempt, scheduled for 6 September 1995, was canceled due to unsatisfactory launch site weather for the ...Such an RPV could clear the fog and search for the downed airman at the same time. To increase the odds of finding the airmen, several RPVs could fly...COBLE A THESIS PRESENTED TO THE FACULTY OF THE SCHOOL OF ADVANCED AIRPOWER STUDIES FOR COMPLETION OF GRADUATION

  20. Landing and Oviposition Responses of Rhagoletis indifferens (Dipt., Tephritidae) on Sweet Cherry Treated with Kaolin- and Limestone-Based Products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Kaolin- and limestone-based products were compared for their effects on landing and oviposition on sweet cherry by Rhagoletis indifferens Curran (Dipt., Tephritidae). Surround (95% calcined kaolin), Cocoon (100% hydrous kaolin), Eclipse (>97% limestone), and Purshade (62.5% limestone) were studied....

  1. Areosynchronous weather imager

    NASA Astrophysics Data System (ADS)

    Puschell, Jeffery J.; Lock, Robert

    2016-09-01

    Mars is characterized by rapidly changing, poorly understood weather that is a concern for future human missions. Future Areosynchronous Mars Orbit (AMO) communication satellites offer possible platforms for Mars weather imagers similar to the geosynchronous Earth orbit (GEO) weather imagers that have been observing Earth since 1966. This paper describes an AReosynchronous Environmental Suite (ARES) that includes two imagers: one with two emissive infrared bands (10.8 μm and 12.0 μm) at 4 km resolution and the other with three VNIR bands (500 nm, 700 nm, 900 nm) at 1 km resolution. ARES stares at Mars and provides full disk coverage as fast as every 40 sec in the VNIR bands and every 2 min in the emissive bands with good sensitivity (SNR 200 in the VNIR for typical radiances and NEDT 0.2K at 180 K scene temperature in the emissive infrared). ARES size, mass, power and data rate characteristics are compatible with expectations for hosted payloads onboard future AMO communication satellites. Nevertheless, more work is needed to optimize ARES for future missions, especially in terms of trades between data rate, full disk coverage rate, sensitivity, number of spectral bands and spatial resolution and in study of approaches for maintaining accurate line of sight knowledge during data collection.

  2. Kazakhstan Space Weather Initiative

    NASA Astrophysics Data System (ADS)

    Kryakunova, Olga

    2012-07-01

    Kazakhstan experimental complex is a center of experimental study of space weather. This complex is situated near Almaty, Kazakhstan and includes experimental setup for registration of cosmic ray intensity (neutron monitor) at altitude of 3340 m above sea level, geomagnetic observatory and setup for registration of solar flux density with frequency of 1 and 3 GHz with 1 second time resolution. Results of space environment monitoring in real time are accessible via Internet. This experimental information is used for space weather investigations and different cosmic ray effects. Almaty mountain cosmic ray station is one of the most suitable and sensitive stations for investigation and forecasting of the dangerous situations for satellites; for this reason Almaty cosmic ray station is included in the world-wide neutron monitor network for the real-time monitoring of the space weather conditions and European Database NMDB (www.nmdb.eu). All data are represented on the web-site of the Institute of Ionosphere (www.ionos.kz) in real time. Since July, 2006 the space environment prediction laboratory represents the forecast of geomagnetic activity every day on the same site (www.ionos.kz/?q=en/node/21).

  3. Particle acceleration

    NASA Technical Reports Server (NTRS)

    Vlahos, L.; Machado, M. E.; Ramaty, R.; Murphy, R. J.; Alissandrakis, C.; Bai, T.; Batchelor, D.; Benz, A. O.; Chupp, E.; Ellison, D.

    1986-01-01

    Data is compiled from Solar Maximum Mission and Hinothori satellites, particle detectors in several satellites, ground based instruments, and balloon flights in order to answer fundamental questions relating to: (1) the requirements for the coronal magnetic field structure in the vicinity of the energization source; (2) the height (above the photosphere) of the energization source; (3) the time of energization; (4) transistion between coronal heating and flares; (5) evidence for purely thermal, purely nonthermal and hybrid type flares; (6) the time characteristics of the energization source; (7) whether every flare accelerates protons; (8) the location of the interaction site of the ions and relativistic electrons; (9) the energy spectra for ions and relativistic electrons; (10) the relationship between particles at the Sun and interplanetary space; (11) evidence for more than one acceleration mechanism; (12) whether there is single mechanism that will accelerate particles to all energies and also heat the plasma; and (13) how fast the existing mechanisms accelerate electrons up to several MeV and ions to 1 GeV.

  4. Plasma accelerator

    DOEpatents

    Wang, Zhehui; Barnes, Cris W.

    2002-01-01

    There has been invented an apparatus for acceleration of a plasma having coaxially positioned, constant diameter, cylindrical electrodes which are modified to converge (for a positive polarity inner electrode and a negatively charged outer electrode) at the plasma output end of the annulus between the electrodes to achieve improved particle flux per unit of power.

  5. Accelerated Achievement

    ERIC Educational Resources Information Center

    Ford, William J.

    2010-01-01

    This article focuses on the accelerated associate degree program at Ivy Tech Community College (Indiana) in which low-income students will receive an associate degree in one year. The three-year pilot program is funded by a $2.3 million grant from the Lumina Foundation for Education in Indianapolis and a $270,000 grant from the Indiana Commission…

  6. ACCELERATION INTEGRATOR

    DOEpatents

    Pope, K.E.

    1958-01-01

    This patent relates to an improved acceleration integrator and more particularly to apparatus of this nature which is gyrostabilized. The device may be used to sense the attainment by an airborne vehicle of a predetermined velocitv or distance along a given vector path. In its broad aspects, the acceleration integrator utilizes a magnetized element rotatable driven by a synchronous motor and having a cylin drical flux gap and a restrained eddy- current drag cap deposed to move into the gap. The angular velocity imparted to the rotatable cap shaft is transmitted in a positive manner to the magnetized element through a servo feedback loop. The resultant angular velocity of tae cap is proportional to the acceleration of the housing in this manner and means may be used to measure the velocity and operate switches at a pre-set magnitude. To make the above-described dcvice sensitive to acceleration in only one direction the magnetized element forms the spinning inertia element of a free gyroscope, and the outer housing functions as a gimbal of a gyroscope.

  7. Stratigraphy and sedimentology of the Upper Cretaceous (Campanian) Anacacho Limestone, Texas, USA

    USGS Publications Warehouse

    Swezey, C.S.; Sullivan, E.C.

    2004-01-01

    The Upper Cretaceous Anacacho Limestone is exposed in outcrops between the cities of San Antonio and Del Rio, Texas. A detailed study of four outcrops (Blanco Creek section, Sabinal River section, Seco Creek section, Hondo Creek section) shows that the Anacacho Limestone rests on the Upson Clay (which contains fauna of early Campanian age) and is overlain by the Corsicana Marl (which contains fauna of early Maastrichtian age). An unconformity within the Anacacho Limestone is used herein to separate the limestone into a lower member and an upper member. The lower Anacacho member contains fauna of early Campanian age, whereas the upper Anacacho member contains fauna of middle Campanian age. The lower Anacacho member consists predominantly of wackestones to packstones, which are overlain by packstones to grainstones capped by the unconformity. This unconformity is interpreted as a marine flooding surface, delineating a transition from carbonate grainstones deposited in shallow water (<30 m depth) to a chalk deposited in deeper water. Above the unconformity, the upper Anacacho member is characterized by a chalk, overlain by wackestones and packstones. The uppermost section of the Anacacho Limestone consists of packstones and grainstones with abundant and diverse fossils. Most of the Anacacho Limestone developed in relatively shallow water (<50 m depth) leeward of a large carbonate build-up (possibly a rudistid reef) that now comprises the Anacacho Mountains. The environment, however, was open to marine water throughout deposition of the Anacacho Limestone. ?? 2004 Elsevier Ltd. All rights reserved.

  8. Preliminary microfacies analysis and cyclicity of the Wahoo Limestone, Lisburne Field, North Slope, Alaska

    SciTech Connect

    Morgan, S.K.; Watts, K.F.

    1995-05-01

    A well from the Lisburne field near Prudhoe Bay was examined in core, thin section, and on well logs for comparison with Wahoo Limestone in the Arctic National Wildlife Refuge (ANWR). Carbonate cycles (parasequences) are well developed in both areas but the greater abundance of terrigenous sediment and associated carbonate facies indicate that the study well is located in a more landward position on the Wahoo carbonate ramp, closer to a source of terrigenous sediment. This report presents the preliminary results of microfacies analyses that have been conducted on 424 of a total 1,115 thin sections from the study well. The stratigraphic nomenclature extended from ANWR (the type locality of the Wahoo Limestone) is different that the terminology previously used for the subsurface Lisburne Group near Prudhoe Bay. We distinguish informal lower and upper members within the Mississippian to Pennsylvanian Wahoo Limestone which overlies the Mississippian Alapah Limestone. Our upper Alapah corresponds to the middle Alapah of previous workers. Our lower Wahoo Limestone member corresponds to the upper Alapah of previous workers. Our upper Wahoo Limestone member corresponds to the previous Wahoo Limestone and is the major hydrocarbon reservoir at the Lisburne field, which is characterized by well-developed carbonate cycles (parasequences).

  9. Space Weathering of Lunar Rocks

    NASA Technical Reports Server (NTRS)

    Noble, S. K.; Keller, L. P.; Christoffersen, R.; Rahman, Z.

    2012-01-01

    All materials exposed at the lunar surface undergo space weathering processes. On the Moon, boulders make up only a small percentage of the exposed surface, and areas where such rocks are exposed, like central peaks, are often among the least space weathered regions identified from remote sensing data. Yet space weathered surfaces (patina) are relatively common on returned rock samples, some of which directly sample the surface of larger boulders. Because, as witness plates to lunar space weathering, rocks and boulders experience longer exposure times compared to lunar soil grains, they allow us to develop a deeper perspective on the relative importance of various weathering processes as a function of time.

  10. ARD remediation with limestone in a CO2 pressurized reactor

    USGS Publications Warehouse

    Sibrell, Philip L.; Watten, Barnaby J.; Friedrich, Andrew E.; Vinci, Brian J.

    2000-01-01

    We evaluated a new process for remediation of acid rock drainage (ARD). The process treats ARD with intermittently fluidized beds of granular limestone maintained within a continuous flow reactor pressurized with CO2. Tests were performed over a thirty day period at the Toby Creek mine drainage treatment plant, Elk County, Pennsylvania in cooperation with the Pennsylvania Department of Environmental Protection. Equipment performance was established at operating pressures of 0, 34, 82, and 117 kPa using an ARD flow of 227 L/min. The ARD had the following characteristics: pH, 3.1; temperature, 10 °C; dissolved oxygen, 6.4 mg/L; acidity, 260 mg/L; total iron, 21 mg/L; aluminum, 22 mg/L; manganese, 7.5 mg/L; and conductivity, 1400 μS/cm. In all cases tested, processed ARD was net alkaline with mean pH and alkalinities of 6.7 and 59 mg/L at a CO2 pressure of 0 kPa, 6.6 and 158 mg/L at 34 kPa, 7.4 and 240 mg/L at 82 kPa, and 7.4 and 290 mg/L at 117 kPa. Processed ARD alkalinities were correlated to the settled bed depth (p<0.001) and CO2 pressure (p<0.001). Iron, aluminum, and manganese removal efficiencies of 96%, 99%, and 5%, respectively, were achieved with filtration following treatment. No indications of metal hydroxide precipitation or armoring of the limestone were observed. The surplus alkalinity established at 82 kPa was successful in treating an equivalent of 1136 L/min (five-fold dilution) of the combined three ARD streams entering the Toby Creek Plant. This side-stream capability provides savings in treatment unit scale as well as flexibility in treatment effect. The capability of the system to handle higher influent acidity was tested by elevating the acidity to 5000 mg/L with sulfuric acid. Net alkaline effluent was produced, indicating applicability of the process to highly acidic ARD.

  11. Rehabilitation of lands mined for limestone in the Indian desert

    USGS Publications Warehouse

    Sharma, K.D.; Kumar, S.; Gough, L.P.

    2000-01-01

    In the Indian desert, the economics of mining is second only to agriculture in importance. However, research on the rehabilitation of land disturbed by mining has only recently received serious attention. An attempt has been made to determine both the qualitative and quantitative success of rehabilitation plans used to revegetate limestone mine spoils in an area near Barna, northwest arid India. Rehabilitation success was achieved using a combination of rainwater harvesting techniques, soil amendment application approaches, plant establishment methods and the selection of appropriate germplasm material (trees, shrubs and grasses). It is expected that the resulting vegetative cover will be capable of self-perpetuation under natural conditions while at the same time meeting the land-use needs of the local people. The minespoils have adequate levels of the major nutrients (except P, Mo and Se) for proper plant and grazing animal health. Levels of organic matter are low whereas total B concentrations are exceptionally high. Also, the population of soil fungi, Azotobactor, and nitrifying bacteria is negligible. Enhanced plant growth was achieved in treated plots, compared to control plots, where spoil moisture storage was improved by 5-45 per cent. Due to the decomposition of farmyard manure and nitrogen fixation by planted leguminous plant species, the electrical conductance of treated mine spoils increased threefold, CaCO3 content decreased from 20??0 to 5??2 per cent, and organic carbon, P, K, and biological activity increased significantly. The rehabilitation protocol used at the site appears to have been successful because plant self-regeneration is occurring. The increased diversity of woody perennials resulted in 'dominance' being better shared among species and 'evenness' being increased within the plant community elements. The early to mid-successional trends are continuing for six years following initial rehabilitation. This study developed methods for the

  12. Salt weathering on Mars

    NASA Astrophysics Data System (ADS)

    Jagoutz, E.

    Large well rounded boulders and angular rock fragments characterizes the Martian landscape as seen on the recent excellent quality photos. Analyzing the different rock-shapes indicates a time sequence of emplacement, fragmentation and transport of different rocks on Mars, which might give interesting insight into transport and weathering processes. Larger commonly well rounded boulders were emplaced onto gravel plains. After emplacement, these rocks were fragmented and disassembled. Nests of angular rock fragments are marking the locations of preexisting larger rocks. Frequently it is possible to reconstruct larger rounded rocks from smaller angular fragments. In other cases transport after fragmentation obscured the relationship of the fragments. However, a strewn field of fragments is still reminiscent of the preexisting rock. Mechanical salt weathering could be a plausible explanation for the insitu fragmentation of larger rounded blocks into angular fragments. Impact or secondary air fall induced fragmentation produces very different patterns, as observed around impact crates on Earth. Salt weathering of rocks is a common process in terrestrial environments. Salt crystallization in capillaries causes fragmentation of rocks, irrespective of the process of salt transportation and concentration. On Earth significant salt weathering can be observed in different climatic environments: in the transition zone of alluvial aprons and salt playas in desserts and in dry valleys of Antarctica. In terrestrial semi-arid areas the salt is transported by salt solution, which is progressively concentrated by evaporation. In Antarctic dry valleys freeze-thaw cycles causes salt transportation and crystallization resulting in rock fragmentation. This salt induced process can lead to complete destruction of rocks and converts rocks to fine sand. The efficient breakdown of rocks is dominating the landscape in some dry valleys of the Earth but possibly also on Mars. (Malin, 1974

  13. Weather dissemination and public usage

    NASA Technical Reports Server (NTRS)

    Stacey, M. S.

    1973-01-01

    The existing public usage of weather information was examined. A survey was conducted to substantiate the general public's needs for dissemination of current (0-12 hours) weather information, needs which, in a previous study, were found to be extensive and urgent. The goal of the study was to discover how the general public obtains weather information, what information they seek and why they seek it, to what use this information is put, and to further ascertain the public's attitudes and beliefs regarding weather reporting and the diffusion of weather information. Major findings from the study include: 1. The public has a real need for weather information in the 0-6 hour bracket. 2. The visual medium is preferred but due to the lack of frequent (0-6 hours) forecasts, the audio media only, i.e., telephone recordings and radio weathercasts, were more frequently used. 3. Weather information usage is sporadic.

  14. Space Weather Services of Korea

    NASA Astrophysics Data System (ADS)

    Yoon, KiChang; Kim, Jae-Hun; Kim, Young Yun; Kwon, Yongki; Wi, Gwan-sik

    2016-07-01

    The Korean Space Weather Center (KSWC) of the National Radio Research Agency (RRA) is a government agency which is the official source of space weather information for Korean Government and the primary action agency of emergency measure to severe space weather condition. KSWC's main role is providing alerts, watches, and forecasts in order to minimize the space weather impacts on both of public and commercial sectors of satellites, aviation, communications, navigations, power grids, and etc. KSWC is also in charge of monitoring the space weather condition and conducting research and development for its main role of space weather operation in Korea. In this study, we will present KSWC's recent efforts on development of application-oriented space weather research products and services on user needs, and introduce new international collaborative projects, such as IPS-Driven Enlil model, DREAM model estimating electron in satellite orbit, global network of DSCOVR and STEREO satellites tracking, and ARMAS (Automated Radiation Measurement for Aviation Safety).

  15. Space Weather Services of Korea

    NASA Astrophysics Data System (ADS)

    Yoon, K.; Hong, S.; Park, S.; Kim, Y. Y.; Wi, G.

    2015-12-01

    The Korean Space Weather Center (KSWC) of the National Radio Research Agency (RRA) is a government agency which is the official source of space weather information for Korean Government and the primary action agency of emergency measure to severe space weather condition. KSWC's main role is providing alerts, watches, and forecasts in order to minimize the space weather impacts on both of public and commercial sectors of satellites, aviation, communications, navigations, power grids, and etc. KSWC is also in charge of monitoring the space weather condition and conducting research and development for its main role of space weather operation in Korea. In this study, we will present KSWC's recent efforts on development of application-oriented space weather research products and services on user needs, and introduce new international collaborative projects, such as IPS-Driven Enlil model, global network of DSCOVR and STEREO satellites tracking, and ARMAS (Automated Radiation Measurement for Aviation Safety).

  16. Millennium-long recession of limestone facades in London

    NASA Astrophysics Data System (ADS)

    Brimblecombe, Peter; Grossi, Carlota M.

    2008-12-01

    Historical data on the temperature and precipitation data for London has been combined with output from the Hadley Model to estimate the climate of London for the period 1100-2100 CE. This has been converted to other parameters such as freeze-thaw frequency and snowfall relevant to the weathering of stone facades. The pollutant concentrations have been estimated for the same period, with the historical values taken from single box modelling and future values from changes likely given current policy within the metropolis. These values are used in the Lipfert model to show that the recession from karst weathering dominates across the period, while the contributions of sulphur deposition seem notable only across a shorter period 1700-2000 CE. Observations of the late seventeenth century suggest London architects witnessed a notable increase in the recession rate and attributed “fretting quality” to “smoaks of the sea-coal”. The recession rates measured in the late twentieth century lend some support to the estimates from the Lipfert model. The recession looks to increase only slightly, and frost shattering will decrease while salt weathering is likely to increase.

  17. Municipalities' Preparedness for Weather Hazards and Response to Weather Warnings

    PubMed Central

    Mehiriz, Kaddour; Gosselin, Pierre

    2016-01-01

    The study of the management of weather-related disaster risks by municipalities has attracted little attention even though these organizations play a key role in protecting the population from extreme meteorological conditions. This article contributes to filling this gap with new evidence on the level and determinants of Quebec municipalities’ preparedness for weather hazards and response to related weather warnings. Using survey data from municipal emergency management coordinators and secondary data on the financial and demographic characteristics of municipalities, the study shows that most Quebec municipalities are sufficiently prepared for weather hazards and undertake measures to protect the population when informed of imminent extreme weather events. Significant differences between municipalities were noted though. Specifically, the level of preparedness was positively correlated with the municipalities’ capacity and population support for weather-related disaster management policies. In addition, the risk of weather-related disasters increases the preparedness level through its effect on population support. We also found that the response to weather warnings depended on the risk of weather-related disasters, the preparedness level and the quality of weather warnings. These results highlight areas for improvement in the context of increasing frequency and/or severity of such events with current climate change. PMID:27649547

  18. Desulfurization with a modified limestone formulation in an industrial CFBC boiler

    SciTech Connect

    Young Goo Park; Seung Ho Kim

    2006-02-01

    This work presents a practical result of experimental investigation of the limestone particle size effect on de-SOx from a circulating fluidized bed combustion (CFBC) boiler that burns domestic anthracite and is the first industrial scale in Korea. Because of combustion problems such as clinker formation, fine limestone has not been used as a desulfurization agent. The present test, however, showed that higher content (up to 50%) of the particles under 0.1 mm did not entail any malfunction in a modern CFBC system. In addition, the desulfurization efficiency was found to be comparable to the old mode of limestone sorbents. 17 refs., 4 figs., 3 tabs.

  19. Effects of particle size distribution on limestone dissolution in wet FGD process applications

    SciTech Connect

    Ukawa, Naohiko; Takashina, Toru; Shinoda, Naoharu ); Shimizu, Taku )

    1993-08-01

    The kinetics of limestone dissolution in the wet type flue gas desulfurization (FGD) processes has been studied. The rates of dissolution and particle size reduction were measured in both batch and continuous reaction systems for limestone of different size distributions. A predictive model was developed based on mass transfer mechanisms. It was in good agreement with experimental data. Moreover, the rate of dissolution for 25 limestones of different compositions and size distributions were measured in apparatus with a sulfur dioxide absorber which simulated FGD processes. The model was also in good agreement with these results. 11 refs., 8 figs., 2 tabs.

  20. Meteoric stabilization and preservation of limestone within late Proterozoic Beck Spring Dolomite of eastern California

    SciTech Connect

    Zempolich, W.G.; Wilkinson, B.H.; Lohmann, K.C.

    1989-04-01

    Petrographic and geochemical study of limestone, silicified carbonate, and dolostone indicates that meteoric diagenetic processes and paleogeographic position played important roles in the stabilization and preservation of limestone within the pervasively dolomitized Beck Spring Dolomite. The authors conclude that Beck Spring marine cement allochems precipitated as aragonite and high-magnesium calcite. In the vicinity of Saratoga Spring, these metastable mineralogies were dissolved, eroded, stabilized to calcite, and replaced by silica through interaction with meteoric waters. Early stabilization of limestone components along the margin of the Amargosa basin apparently decreased susceptibility to subsequent dolomitization.

  1. A procedure to evaluate environmental rehabilitation in limestone quarries.

    PubMed

    Neri, Ana Claudia; Sánchez, Luis Enrique

    2010-11-01

    A procedure to evaluate mine rehabilitation practices during the operational phase was developed and validated. It is based on a comparison of actually observed or documented practices with internationally recommended best practices (BP). A set of 150 BP statements was derived from international guides in order to establish the benchmark. The statements are arranged in six rehabilitation programs under three categories: (1) planning (2) operational and (3) management, corresponding to the adoption of the plan-do-check-act management systems model to mine rehabilitation. The procedure consists of (i) performing technical inspections guided by a series of field forms containing BP statements; (ii) classifying evidences in five categories; and (iii) calculating conformity indexes and levels. For testing and calibration purposes, the procedure was applied to nine limestone quarries and conformity indexes were calculated for the rehabilitation programs in each quarry. Most quarries featured poor planning practices, operational practices reached high conformity levels in 50% of the cases and management practices scored moderate conformity. Despite all quarries being ISO 14001 certified, their management systems pay low attention to issues pertaining to land rehabilitation and biodiversity. The best results were achieved by a quarry whose expansion was recently submitted to the environmental impact assessment process, suggesting that public scrutiny may play a positive role in enhancing rehabilitation practices. Conformity indexes and levels can be used to chart the evolution of rehabilitation practices at regular intervals, to establish corporate goals and for communication with stakeholders.

  2. Transport studies of radon in limestone underlying houses

    SciTech Connect

    Gammage, R.B.; Dudney, C.S.; Wilson, D.L.; Saultz, R.J.

    1990-01-01

    In hilly limestone terrains of the southern Appalachians, subterranean networks of solution cavities and fissures present circulatory systems facilitating convective and advective transport of radon-bearing gas. Evidence suggests that the primary driving forces for transport are aerostatic pressure differentials created by the difference between the underground and the outside air temperatures. Examples are presented of houses experiencing elevated indoor radon levels as a consequence of communicating with such subsurface transportation systems. The location of a house near the upper or lower end of a subterranean-circulatory system seems to produce amplification of indoor radon levels in winter or summer, respectively. The transport mechanism for radon-bearing air in karst and its impact on indoor radon need better understanding, both in regard to evaluating the geographical prevalence of the phenomenon and the induced spatial and temporal effects that are possible. This paper reports field studies made at houses in karst regions at Oak Ridge, Tennessee, and Huntsville, Alabama. A primary radon-transport mechanism is advocated of ascending or descending subsurface columns of air whose flows are largely driven by aerostatic pressure gradients created by the inground-outdoor air temperature differentials. 5 refs., 5 figs., 1 tab.

  3. Colour changes by laser irradiation of reddish building limestones

    NASA Astrophysics Data System (ADS)

    Grossi, C. M.; Benavente, D.

    2016-10-01

    We have used X-ray photoelectron spectroscopy (XPS) as a novel method to investigate the causes of colour changes in a reddish limestone under irradiation by a Q-switched Nd:YAG 1064 nm laser. We irradiated clean dry and wet surfaces of Pidramuelle Roja, a building stone frequently used in the Asturian heritage, at fluences ranging from 0.12 to 1.47 J cm-2. We measured the colour coordinates and undertook XPS analysis of the state of oxidation of iron both before and after irradiation. Visible colour changes and potential aesthetic damage occurred on dry surfaces from a fluence of 0.31 J cm-2, with the stone showing a greening effect and very intense darkening. The colour change on dry surfaces was considerably higher than on wet surfaces, which at the highest fluence (1.47 J cm-2) was also above the human visual detection threshold. The use of XPS demonstrated that the change in colour (chroma and hue) is associated with a reduction in the iron oxidation state on dry surfaces during laser irradiation. This points out to a potential routinary use of XPS to analyse causes of colour changes during laser cleaning in other types of coloured building stones.

  4. Factors affecting floral herbivory in a limestone grassland

    NASA Astrophysics Data System (ADS)

    Breadmore, Karen N.; Kirk, William D. J.

    1998-12-01

    The amount of herbivore damage to the petals of 41 species of herbaceous plant was surveyed from April to September in a limestone grassland in central England. Damage was recorded as the percentage of the petal area removed. Most damage was caused by invertebrates, particularly slugs. The amount of invertebrate damage differed significantly between plant species and with time of year. The mean damage across all species was only 2 %, ranging from an average of 0 % in Galium sterneri to 8 % in Primula vulgaris. In most species, less than a quarter of flowers received any damage, so those that were damaged were often severely affected. Species flowering early or late in the season received more damage, possibly because of greater slug activity. Hypotheses to explain the inter-specific variation in the amount of herbivory were examined by testing for correlations with a range of plant variables. No correlations with flower-stem length, flower-stem thickness or the longevity of flowers were apparent. The amount of petal damage correlated strongly with flower size and petal thickness. This appeared to result from the prevalence of large-flowered species early and late in the season rather than from a preference for flower size and petal thickness per se. The evolutionary significance of floral herbivory is discussed.

  5. The Surface of a Limestone-Rich World?

    NASA Astrophysics Data System (ADS)

    Melis, Carl; Dufour, Patrick

    2016-06-01

    We present spectroscopic observations of the dust- and gas-enshrouded, polluted white dwarf star SDSSJ104341.53+085558.2 (hereafter SDSSJ1043). Hubble Space Telescope Cosmic Origins Spectrograph far-ultraviolet spectra combined with deep Keck HIRES optical spectroscopy reveal the elements C, O, Mg, Al, Si, P, S, Ca, Fe, and Ni and enable useful limits for Sc, Ti, V, Cr, and Mn in the photosphere of SDSSJ1043. From this suite of elements we determine that the parent body being accreted by SDSSJ1043 is dry, rocky, and iron-poor. Synthesizing all available heavily-polluted white dwarf measurements, we find a trend in the Fe/Mg vs Fe/Si abundance ratio-space suggestive of whether accreted material originates from the inner or outer regions of a rocky body; we use this trend to identify the material being accreted by SDSSJ1043 as likely to have come from the outermost layers of a differentiated object. Enhanced levels of Ca and C in this object can be explained by the presence of significant amounts of calcium-carbonate and, if definitive, could be suggestive of a world with a crust rich in limestone.

  6. Mechanisms of time-dependent deformation in porous limestone

    NASA Astrophysics Data System (ADS)

    Brantut, Nicolas; Heap, Michael J.; Baud, Patrick; Meredith, Philip G.

    2014-07-01

    We performed triaxial deformation experiments on a water-saturated porous limestone under constant strain rate and constant stress (creep) conditions. The tests were conducted at room temperature and at low effective pressures Peff=10 and Peff=20 MPa, in a regime where the rock is nominally brittle when tested at a constant strain rate of 10-5 s-1. Under these conditions and at constant stress, the phenomenon of brittle creep occurs. At Peff=10 MPa, brittle creep follows similar trends as those observed in other rock types (e.g., sandstones and granites): only small strains are accumulated before failure, and damage accumulation with increasing strain (as monitored by P wave speeds measurements during the tests) is not strongly dependent on the applied stresses. At Peff=20 MPa, brittle creep is also macroscopically observed, but when the creep strain rate is lower than ≈10-7 s-1, we observe that (1) much larger strains are accumulated, (2) less damage is accumulated with increasing strain, and (3) the deformation tends to be more compactant. These observations can be understood by considering that another deformation mechanism, different from crack growth, is active at low strain rates. We explore this possibility by constructing a deformation mechanism map that includes both subcritical crack growth and pressure solution creep processes; the increasing contribution of pressure solution creep at low strain rates is consistent with our observations.

  7. Multispectral analysis of limestone, dolomite, and granite, Mill Creek, Oklahoma

    NASA Technical Reports Server (NTRS)

    Rowan, L. C.; Watson, K.

    1970-01-01

    Spectral reflectance and thermal emission data were collected at the Mill Creek, Oklahoma test site during NASA missions 132 and 133 in June 1970. The data were collected by three aircraft flown several times during the diurnal cycle at altitudes of 150 to 17,000 m above mean terrain. Reflectance of the main rock types (limestone, dolomite, and granite) was determined from the data collected using a 12-channel multispectral scanner during mission 133 and from thermal infrared images recorded during mission 132 on an RS-7 scanner from 17,000 m above terrain. A preliminary rock recognition map was generated automatically using data collected from 900 m above terrain. The discrimination provided by the map is reasonably accurate. Misidentification occurred in areas of unusually high dolomite reflectivity. High altitude thermal infrared (10 to 12 micrometers) images show regional folds and faults distinguished by the presence of thermally contrasting materials. Linear and curvilinear structural features two to three times smaller than the nominal 17 m resolution could be detected.

  8. Solar Sources of Severe Space Weather

    NASA Technical Reports Server (NTRS)

    Gopalswamy, N.; Yashiro, S.; Shibasaki, K.

    2012-01-01

    Severe space weather is characterized by intense particle radiation from the Sun and severe geomagnetic storm caused by magnetized solar plasma arriving at Earth. Intense particle radiation is almost always caused by coronal mass ejections (CMEs) traveling from the Sun at super-Alfvenic speeds leading to fast-mode MHD shocks and particle acceleration by the shocks. When a CME arrives at Earth, it can interact with Earth's magnetopause resulting in solar plasma entry into the magnetosphere and a geomagnetic storm depending on the magnetic structure of the CME. Particle radiation starts affecting geospace as soon as the CMEs leave the Sun and the geospace may be immersed in the radiation for several days. On the other hand, the geomagnetic storm happens only upon arrival of the CME at Earth. The requirements for the production of particles and magnetic storms by CMEs are different in a number of respects: solar source location, CME magnetic structure, conditions in the ambient solar wind, and shock-driving ability of CMEs. Occasionally, intense geomagnetic storms are caused by corotating interaction regions (CIRs) that form in the interplanetary space when the fast solar wind from coronal holes overtakes the slow wind from the quiet regions. CIRs also accelerate particles, but when they reach several AU from the Sun, so their impact on Earth's space environment is not significant. In addition to these plasma effects, solar flares that accompany CMEs also produce excess ionization in the ionosphere causing sudden ionospheric disturbances. This paper highlights these space weather effects using space weather events observed by space and ground based instruments during of solar cycles 23 and 24.

  9. Particle Accelerators in China

    NASA Astrophysics Data System (ADS)

    Zhang, Chuang; Fang, Shouxian

    As the special machines that can accelerate charged particle beams to high energy by using electromagnetic fields, particle accelerators have been widely applied in scientific research and various areas of society. The development of particle accelerators in China started in the early 1950s. After a brief review of the history of accelerators, this article describes in the following sections: particle colliders, heavy-ion accelerators, high-intensity proton accelerators, accelerator-based light sources, pulsed power accelerators, small scale accelerators, accelerators for applications, accelerator technology development and advanced accelerator concepts. The prospects of particle accelerators in China are also presented.

  10. Compact accelerator

    DOEpatents

    Caporaso, George J.; Sampayan, Stephen E.; Kirbie, Hugh C.

    2007-02-06

    A compact linear accelerator having at least one strip-shaped Blumlein module which guides a propagating wavefront between first and second ends and controls the output pulse at the second end. Each Blumlein module has first, second, and third planar conductor strips, with a first dielectric strip between the first and second conductor strips, and a second dielectric strip between the second and third conductor strips. Additionally, the compact linear accelerator includes a high voltage power supply connected to charge the second conductor strip to a high potential, and a switch for switching the high potential in the second conductor strip to at least one of the first and third conductor strips so as to initiate a propagating reverse polarity wavefront(s) in the corresponding dielectric strip(s).

  11. Severe Weather Forecast Decision Aid

    NASA Technical Reports Server (NTRS)

    Bauman, William H., III; Wheeler, Mark M.; Short, David A.

    2005-01-01

    This report presents a 15-year climatological study of severe weather events and related severe weather atmospheric parameters. Data sources included local forecast rules, archived sounding data, Cloud-to-Ground Lightning Surveillance System (CGLSS) data, surface and upper air maps, and two severe weather event databases covering east-central Florida. The local forecast rules were used to set threat assessment thresholds for stability parameters that were derived from the sounding data. The severe weather events databases were used to identify days with reported severe weather and the CGLSS data was used to differentiate between lightning and non-lightning days. These data sets provided the foundation for analyzing the stability parameters and synoptic patterns that were used to develop an objective tool to aid in forecasting severe weather events. The period of record for the analysis was May - September, 1989 - 2003. The results indicate that there are certain synoptic patterns more prevalent on days with severe weather and some of the stability parameters are better predictors of severe weather days based on locally tuned threat values. The results also revealed the stability parameters that did not display any skill related to severe weather days. An interactive web-based Severe Weather Decision Aid was developed to assist the duty forecaster by providing a level of objective guidance based on the analysis of the stability parameters, CGLSS data, and synoptic-scale dynamics. The tool will be tested and evaluated during the 2005 warm season.

  12. Laser acceleration

    NASA Astrophysics Data System (ADS)

    Tajima, T.; Nakajima, K.; Mourou, G.

    2017-02-01

    The fundamental idea of Laser Wakefield Acceleration (LWFA) is reviewed. An ultrafast intense laser pulse drives coherent wakefield with a relativistic amplitude robustly supported by the plasma. While the large amplitude of wakefields involves collective resonant oscillations of the eigenmode of the entire plasma electrons, the wake phase velocity ˜ c and ultrafastness of the laser pulse introduce the wake stability and rigidity. A large number of worldwide experiments show a rapid progress of this concept realization toward both the high-energy accelerator prospect and broad applications. The strong interest in this has been spurring and stimulating novel laser technologies, including the Chirped Pulse Amplification, the Thin Film Compression, the Coherent Amplification Network, and the Relativistic Mirror Compression. These in turn have created a conglomerate of novel science and technology with LWFA to form a new genre of high field science with many parameters of merit in this field increasing exponentially lately. This science has triggered a number of worldwide research centers and initiatives. Associated physics of ion acceleration, X-ray generation, and astrophysical processes of ultrahigh energy cosmic rays are reviewed. Applications such as X-ray free electron laser, cancer therapy, and radioisotope production etc. are considered. A new avenue of LWFA using nanomaterials is also emerging.

  13. BICEP's acceleration

    SciTech Connect

    Contaldi, Carlo R.

    2014-10-01

    The recent Bicep2 [1] detection of, what is claimed to be primordial B-modes, opens up the possibility of constraining not only the energy scale of inflation but also the detailed acceleration history that occurred during inflation. In turn this can be used to determine the shape of the inflaton potential V(φ) for the first time — if a single, scalar inflaton is assumed to be driving the acceleration. We carry out a Monte Carlo exploration of inflationary trajectories given the current data. Using this method we obtain a posterior distribution of possible acceleration profiles ε(N) as a function of e-fold N and derived posterior distributions of the primordial power spectrum P(k) and potential V(φ). We find that the Bicep2 result, in combination with Planck measurements of total intensity Cosmic Microwave Background (CMB) anisotropies, induces a significant feature in the scalar primordial spectrum at scales k∼ 10{sup -3} Mpc {sup -1}. This is in agreement with a previous detection of a suppression in the scalar power [2].

  14. Weather Forecasting Aid

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Weather forecasters are usually very precise in reporting such conditions as temperature, wind velocity and humidity. They also provide exact information on barometric pressure at a given moment, and whether the barometer is "rising" or "falling"- but not how rapidly or how slowly it is rising or falling. Until now, there has not been available an instrument which measures precisely the current rate of change of barometric pressure. A meteorological instrument called a barograph traces the historical ups and downs of barometric pressure and plots a rising or falling curve, but, updated every three hours, it is only momentarily accurate at each updating.

  15. Weather Radar Studies

    DTIC Science & Technology

    1988-03-31

    Reflectivity Core Recognition 68 IV-10 Middle-Level Precursor Recognition 69 IV-l I Early Microburst Hazard Declaration 70 IV-12 Example of Results from...Denver Test Bed 106 V-I Selected Product Types 14 V-2 Encoded Map Size (in ELMs ) for Terminal Map Data Set 119 V-3 Encoded Map Size (in ELMs ) for En...Route Data Sets 119 V-4 Encoded Map Size (in ELMs ) for Terminal Map Data Set 125 xiii WEATHER RADAR STUDIES 1. INTRODUCTION The principal areas of

  16. Boulders, biology and buildings: Why weathering is vital to geomorphology (Ralph Alger Bagnold Medal Lecture)

    NASA Astrophysics Data System (ADS)

    Viles, Heather A.

    2015-04-01

    range of settings including rocky coasts. The concept of bioprotection has also been explored within the context of weathering in deserts and other environments. Practical applications of geomorphological knowledge on weathering (including biogeomorphic aspects) have burgeoned in recent years. In conceptual terms, non-linear dynamical systems ideas have been applied to stone deterioration and the concept of durability, and biogeomorphic disturbance ideas expanded to investigate the impact of climate change on biota growing on stone heritage. The concept of bioprotection has been applied fruitfully to heritage conservation practice. Empirical investigations, for example of cavernous weathering on limestone buildings and green algal growths on sandstone structures, illustrate the application of new methods. Future research should enhance the vitality of weathering studies, through making better use of innovative technologies and improving cross-disciplinary research.

  17. GEOSS interoperability for Weather, Ocean and Water

    NASA Astrophysics Data System (ADS)

    Richardson, David; Nyenhuis, Michael; Zsoter, Ervin; Pappenberger, Florian

    2013-04-01

    "Understanding the Earth system — its weather, climate, oceans, atmosphere, water, land, geodynamics, natural resources, ecosystems, and natural and human-induced hazards — is crucial to enhancing human health, safety and welfare, alleviating human suffering including poverty, protecting the global environment, reducing disaster losses, and achieving sustainable development. Observations of the Earth system constitute critical input for advancing this understanding." With this in mind, the Group on Earth Observations (GEO) started implementing the Global Earth Observation System of Systems (GEOSS). GEOWOW, short for "GEOSS interoperability for Weather, Ocean and Water", is supporting this objective. GEOWOW's main challenge is to improve Earth observation data discovery, accessibility and exploitability, and to evolve GEOSS in terms of interoperability, standardization and functionality. One of the main goals behind the GEOWOW project is to demonstrate the value of the TIGGE archive in interdisciplinary applications, providing a vast amount of useful and easily accessible information to the users through the GEO Common Infrastructure (GCI). GEOWOW aims at developing funcionalities that will allow easy discovery, access and use of TIGGE archive data and of in-situ observations, e.g. from the Global Runoff Data Centre (GRDC), to support applications such as river discharge forecasting.TIGGE (THORPEX Interactive Grand Global Ensemble) is a key component of THORPEX: a World Weather Research Programme to accelerate the improvements in the accuracy of 1-day to 2 week high-impact weather forecasts for the benefit of humanity. The TIGGE archive consists of ensemble weather forecast data from ten global NWP centres, starting from October 2006, which has been made available for scientific research. The TIGGE archive has been used to analyse hydro-meteorological forecasts of flooding in Europe as well as in China. In general the analysis has been favourable in terms of

  18. NASA Space Weather Center Services: Potential for Space Weather Research

    NASA Technical Reports Server (NTRS)

    Zheng, Yihua; Kuznetsova, Masha; Pulkkinen, Antti; Taktakishvili, A.; Mays, M. L.; Chulaki, A.; Lee, H.; Hesse, M.

    2012-01-01

    The NASA Space Weather Center's primary objective is to provide the latest space weather information and forecasting for NASA's robotic missions and its partners and to bring space weather knowledge to the public. At the same time, the tools and services it possesses can be invaluable for research purposes. Here we show how our archive and real-time modeling of space weather events can aid research in a variety of ways, with different classification criteria. We will list and discuss major CME events, major geomagnetic storms, and major SEP events that occurred during the years 2010 - 2012. Highlights of major tools/resources will be provided.

  19. Primary deforestation and regrowth on limestone slopes on Vancouver Island, British Columbia

    SciTech Connect

    Harding, K.A.; Ford, D.C. . Dept. of Geography)

    1992-01-01

    Limestones, well bedded and steeply dipping, are common in northern Vancouver Island. They have been glaciated and host a high density of postglacial karren (dissolution pits, grooves and troughs linked to underlying caves). There is rich, mature forest cover of western hemlock, silver fir and red cedar that is rooted in the karren or in overlying glacial deposits. Logging commenced around 1900 AD, intensifying after 1960 with clear cutting and (often) burning of slash. Impacts were investigated quantitatively by comparing sixteen limestone sites with eight on adjoining volcanic rocks. Some sites on each retained original forest, other were cleared. It was found that soil losses following logging are significantly greater on the limestones because of wash into karren (the epikarst zone). Regrowth is retarded on the limestones also; one site cleared in 1911 had regained approximately 17% of its original volume of timber 75 years later.

  20. Weight losses of marble and limestone briquettes exposed to outdoor environments in the eastern United States

    SciTech Connect

    Youngdahl, C.A.

    1987-08-01

    Weight losses of marble and limestone samples exposed to outdoor environments at field sites in the eastern United States have been monitored in studies initiated in 1984. The prodcedures are described, and the results are tabulated and discussed. A rate of marble loss approximately equivalent to 16 ..mu..m of surface recession per year was found in North Carolina, and losses of this order were also observed in New Jersey, New York, and Washington, DC. Limestone weight losses were much higher than for marble in the first year; loss of extraneous materials from the porous limestone appeared to be a likely contributor to the overall loss. The rate of limestone loss diminished in the second year, though it continued to be higher than for marble. Exposures are continuing in a planned 10-yr program of tests. 8 refs., 3 figs., 5 tabs.

  1. Road Weather and Connected Vehicles

    NASA Astrophysics Data System (ADS)

    Pisano, P.; Boyce, B. C.

    2015-12-01

    On average, there are over 5.8 M vehicle crashes each year of which 23% are weather-related. Weather-related crashes are defined as those crashes that occur in adverse weather or on slick pavement. The vast majority of weather-related crashes happen on wet pavement (74%) and during rainfall (46%). Connected vehicle technologies hold the promise to transform road-weather management by providing improved road weather data in real time with greater temporal and geographic accuracy. This will dramatically expand the amount of data that can be used to assess, forecast, and address the impacts that weather has on roads, vehicles, and travelers. The use of vehicle-based measurements of the road and surrounding atmosphere with other, more traditional weather data sources, and create road and atmospheric hazard products for a variety of users. The broad availability of road weather data from mobile sources will vastly improve the ability to detect and forecast weather and road conditions, and will provide the capability to manage road-weather response on specific roadway links. The RWMP is currently demonstrating how weather, road conditions, and related vehicle data can be used for decision making through an innovative Integrated Mobile Observations project. FHWA is partnering with 3 DOTs (MN, MI, & NV) to pilot these applications. One is a mobile alerts application called the Motorists Advisories and Warnings (MAW) and a maintenance decision support application. These applications blend traditional weather information (e.g., radar, surface stations) with mobile vehicle data (e.g., temperature, brake status, wiper status) to determine current weather conditions. These weather conditions, and other road-travel-relevant information, are provided to users via web and phone applications. The MAW provides nowcasts and short-term forecasts out to 24 hours while the EMDSS application can provide forecasts up to 72 hours in advance. The three DOTs have placed readers and external

  2. Weatherization Apprenticeship Program

    SciTech Connect

    Watson, Eric J

    2012-12-18

    Weatherization improvement services will be provided to Native people by Native people. The proposed project will recruit, train and hire two full-time weatherization technicians who will improve the energy efficiency of homes of Alaska Natives/American Indians residing in the Indian areas, within the Cook Inlet Region of Alaska. The Region includes Anchorage as well as 8 small tribal villages: The Native Villages of Eklutna, Knik, Chickaloon, Seldovia, Ninilchik, Kenaitze, Salamatof, and Tyonek. This project will be a partnership between three entities, with Cook Inlet Tribal Council (CITC) as the lead agency: CITCA's Employment and Training Services Department, Cook Inlet Housing Authority and Alaska Works Partnership. Additionally, six of the eight tribal villages within the Cook Inlet Region of Alaska have agreed to work with the project in order to improve the energy efficiency of their tribally owned buildings and homes. The remaining three villages will be invited to participate in the establishment of an intertribal consortium through this project. Tribal homes and buildings within Anchorage fall under Cook Inlet Region, Inc. (CIRI) tribal authority.

  3. Weathering of rock 'Ginger'

    NASA Technical Reports Server (NTRS)

    1997-01-01

    One of the more unusual rocks at the site is Ginger, located southeast of the lander. Parts of it have the reddest color of any material in view, whereas its rounded lobes are gray and relatively unweathered. These color differences are brought out in the inset, enhanced at the upper right. In the false color image at the lower right, the shape of the visible-wavelength spectrum (related to the abundance of weathered ferric iron minerals) is indicated by the hue of the rocks. Blue indicates relatively unweathered rocks. Typical soils and drift, which are heavily weathered, are shown in green and flesh tones. The very red color in the creases in the rock surface correspond to a crust of ferric minerals. The origin of the rock is uncertain; the ferric crust may have grown underneath the rock, or it may cement pebbles together into a conglomerate. Ginger will be a target of future super-resolution studies to better constrain its origin.

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator. JPL is an operating division of the California Institute of Technology (Caltech).

  4. Size and performance of anoxic limestone drains to neutralize acdic mine drainagei

    USGS Publications Warehouse

    Cravotta, C.A.

    2003-01-01

    Acidic mine drainage (AMD) can be neutralized effectively in underground, anoxic limestone drains (ALDs). Owing to reaction between the AMD and limestone (CaCO3), the pH and concentrations of alkalinity and calcium increase asymptotically with detention time in the ALD, while concentrations of sulfate, ferrous iron, and manganese typically are unaffected. This paper introduces a method to predict the alkalinity produced within an ALD and to estimate the mass of limestone required for its construction on the basis of data from short-term, closed-container (cubitainer) tests. The cubitainer tests, which used an initial mass of 4 kg crushed limestone completely inundated with 2.8 L AMD, were conducted for 11 to 16 d and provided estimates for the initial and maximum alkalinities and corresponding rates of alkalinity production and limestone dissolution. Long-term (5-11 yr) data for alkalinity and CaCO3 flux at the Howe Bridge, Morrison, and Buck Mountain ALDs in Pennsylvania, USA, indicate that rates of alkalinity production and limestone dissolution under field conditions were comparable with those in cubitainers filled with limestone and AMD from each site. The alkalinity of effluent and intermediate samples along the flow path through the ALDs and long-term trends in the residual mass of limestone and the effluent alkalinity were estimated as a function of the computed detention time within the ALD and second-order dissolution rate models for cubitainer tests. Thus, cubitainer tests can be a useful tool for designing ALDs and predicting their performance.

  5. Size and performance of anoxic limestone drains to neutralize acidic mine drainage.

    PubMed

    Cravotta, Charles A

    2003-01-01

    Acidic mine drainage (AMD) can be neutralized effectively in underground, anoxic limestone drains (ALDs). Owing to reaction between the AMD and limestone (CaCO3), the pH and concentrations of alkalinity and calcium increase asymptotically with detention time in the ALD, while concentrations of sulfate, ferrous iron, and manganese typically are unaffected. This paper introduces a method to predict the alkalinity produced within an ALD and to estimate the mass of limestone required for its construction on the basis of data from short-term, closed-container (cubitainer) tests. The cubitainer tests, which used an initial mass of 4 kg crushed limestone completely inundated with 2.8 L AMD, were conducted for 11 to 16 d and provided estimates for the initial and maximum alkalinities and corresponding rates of alkalinity production and limestone dissolution. Long-term (5-11 yr) data for alkalinity and CaCO3 flux at the Howe Bridge, Morrison, and Buck Mountain ALDs in Pennsylvania, USA, indicate that rates of alkalinity production and limestone dissolution under field conditions were comparable with those in cubitainers filled with limestone and AMD from each site. The alkalinity of effluent and intermediate samples along the flow path through the ALDs and long-term trends in the residual mass of limestone and the effluent alkalinity were estimated as a function of the computed detention time within the ALD and second-order dissolution rate models for cubitainer tests. Thus, cubitainer tests can be a useful tool for designing ALDs and predicting their performance.

  6. Weather Forecasting Systems and Methods

    NASA Technical Reports Server (NTRS)

    Mecikalski, John (Inventor); MacKenzie, Wayne M., Jr. (Inventor); Walker, John Robert (Inventor)

    2014-01-01

    A weather forecasting system has weather forecasting logic that receives raw image data from a satellite. The raw image data has values indicative of light and radiance data from the Earth as measured by the satellite, and the weather forecasting logic processes such data to identify cumulus clouds within the satellite images. For each identified cumulus cloud, the weather forecasting logic applies interest field tests to determine a score indicating the likelihood of the cumulus cloud forming precipitation and/or lightning in the future within a certain time period. Based on such scores, the weather forecasting logic predicts in which geographic regions the identified cumulus clouds will produce precipitation and/or lighting within during the time period. Such predictions may then be used to provide a weather map thereby providing users with a graphical illustration of the areas predicted to be affected by precipitation within the time period.

  7. Weather forecasting expert system study

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Weather forecasting is critical to both the Space Transportation System (STS) ground operations and the launch/landing activities at NASA Kennedy Space Center (KSC). The current launch frequency places significant demands on the USAF weather forecasters at the Cape Canaveral Forecasting Facility (CCFF), who currently provide the weather forecasting for all STS operations. As launch frequency increases, KSC's weather forecasting problems will be great magnified. The single most important problem is the shortage of highly skilled forecasting personnel. The development of forecasting expertise is difficult and requires several years of experience. Frequent personnel changes within the forecasting staff jeopardize the accumulation and retention of experience-based weather forecasting expertise. The primary purpose of this project was to assess the feasibility of using Artificial Intelligence (AI) techniques to ameliorate this shortage of experts by capturing aria incorporating the forecasting knowledge of current expert forecasters into a Weather Forecasting Expert System (WFES) which would then be made available to less experienced duty forecasters.

  8. Effect of temperature, hydraulic residence time and elevated PCO2 on acid neutralization within a pulsed limestone bed reactor

    USGS Publications Warehouse

    Watten, B.J.; Lee, P.C.; Sibrell, P.L.; Timmons, M.B.

    2007-01-01

    Limestone has potential for reducing reagent costs and sludge volume associated with treatment of acid mine drainage, but its use is restricted by slow dissolution rates and the deposition of Fe, Al and Mn-based hydrolysis products on reactive surfaces. We evaluated a pulsed limestone bed (PLB) reactor (15 L/min capacity) that uses a CO2 pretreatment step to accelerate dissolution and hydraulic shearing forces provided by intermittent fluidization to abrade and carry away surface scales. We established the effects of hydraulic residence time (HRT, 5.1-15.9 min), temperature (T, 12-22 ??C) and CO2 tension (PCO2, 34.5-206.8 kPa) on effluent quality when inlet acidity (Acy) was fixed at 440 mg/L (pH=2.48) with H2SO4. The PLB reactor neutralized all H+ acidity (N=80) while concurrently providing unusually high levels of effluent alkalinity (247-1028 mg/L as CaCO3) that allow for side-stream treatment with blending. Alkalinity (Alk) yields rose with increases in PCO2, HRT and settled bed height (BH, cm) and decreased with T following the relationship (R2=0.926; p<0.001): (Alk)non-filtered=-548.726+33.571??(PCO2)0.5+33.671??(HRT)+7.734??(BH)-5.197??(T). Numerical modeling showed CO2 feed requirements for a target Alk yield decrease with increases in HRT, T and the efficiency of off-gas (CO2) recycling. ?? 2007 Elsevier Ltd. All rights reserved.

  9. Advanced concepts for acceleration

    SciTech Connect

    Keefe, D.

    1986-07-01

    Selected examples of advanced accelerator concepts are reviewed. Such plasma accelerators as plasma beat wave accelerator, plasma wake field accelerator, and plasma grating accelerator are discussed particularly as examples of concepts for accelerating relativistic electrons or positrons. Also covered are the pulsed electron-beam, pulsed laser accelerator, inverse Cherenkov accelerator, inverse free-electron laser, switched radial-line accelerators, and two-beam accelerator. Advanced concepts for ion acceleration discussed include the electron ring accelerator, excitation of waves on intense electron beams, and two-wave combinations. (LEW)

  10. Accelerators and the Accelerator Community

    SciTech Connect

    Malamud, Ernest; Sessler, Andrew

    2008-06-01

    In this paper, standing back--looking from afar--and adopting a historical perspective, the field of accelerator science is examined. How it grew, what are the forces that made it what it is, where it is now, and what it is likely to be in the future are the subjects explored. Clearly, a great deal of personal opinion is invoked in this process.

  11. Techniques to improve the economics of limestone FGDS

    SciTech Connect

    Bresowar, G.E.; Klingspor, J.

    1995-12-31

    Many utilities have evaluated the cost of scrubbing versus fuel switching in various plans and scenarios to determine the most economical means for meeting the requirements of the new law. Presently, the future cost of removing a ton of SO{sub 2} is based on fuel switching, and the market values are in the range of $150 - $250 per ton. The perceived cost of FGDS retrofits is $250 - $400 per ton for eastern medium to high sulfur coal. ABB has studied the overall costs of FGDS and has developed a series of cost reducing improvements. and innovations. The improvements are manifested in ABBs new limestone FGDS technology known by the code phrase {open_quote}Stealth FGDS{close_quotes}. Stealth promises low capital and operating cost, high removal efficiencies for SO{sub 2} and other pollutants, little or positive environmental and economic impact on the local community, salable or non-hazardous by-products, ease of retrofit, and exceptionally short installation schedules. The concepts are being demonstrated in one system at the Miles Generating Station of Ohio Edison Company. Bearing the name {open_quote}LS-2 Advanced SO, Scrubbing{close_quotes}, the Stealth scrubber at Niles is a 110 MWe turnkey, retrofit unit to be completed 20 months after the release of engineering. It will remove 20,000 or more tons per year of SO{sub 2} from the flue gases generated by both Unit 1 and Unit 2 boilers, producing wallboard-grade gypsum. Upon completion of a four month test program, the plant will be operated by Ohio Edison for a four to five year reliability demonstration period. The performance and economic projections for LS-2 scrubbers show the technology to be quite attractive relative to projections for fuel switching when installed in a manner similar to the installation plan for Niles. The description and basis for these economic projections are described in this paper.

  12. Mangrove plantation over a limestone reef - Good for the ecology?

    NASA Astrophysics Data System (ADS)

    Asaeda, Takashi; Barnuevo, Abner; Sanjaya, Kelum; Fortes, Miguel D.; Kanesaka, Yoshikazu; Wolanski, Eric

    2016-05-01

    There have been efforts to restore degraded tropical and subtropical mangrove forests. While there have been many failures, there have been some successes but these were seldom evaluated to test to what level the created mangrove wetlands reproduce the characteristics of the natural ecosystem and thus what ecosystem services they can deliver. We provide such a detailed assessment for the case of Olango and Banacon Islands in the Philippines where the forest was created over a limestone reef where mangroves did not exist in one island but they covered most of the other island before deforestation in the 1940s and 1950s. The created forest appears to have reached a steady state after 60 years. As is typical of mangrove rehabilitation efforts worldwide, planting was limited to a single Rhizophora species. While a forest has been created, it does not mimic a natural forest. There is a large difference between the natural and planted forests in terms of forest structure and species diversity, and tree density. The high density of planted trees excludes importing other species from nearby natural forests; therefore the planted forest remains mono-specific even after several decades and shows no sign of mimicking the characteristics of a natural forest. The planted forests provided mangrove propagules that invaded nearby natural forests. The planted forest has also changed the substratum from sandy to muddy. The outline of the crown of the planted forest has become smooth and horizontal, contrary to that of a natural forest, and this changes the local landscape. Thus we recommend that future mangrove restoration schemes should modify their methodology in order to plant several species, maintain sufficient space between trees for growth, include the naturally dominant species, and create tidal creeks, in order to reproduce in the rehabilitated areas some of the key ecosystem characteristics of natural mangrove forests.

  13. The Origin of "Space Weather"

    NASA Astrophysics Data System (ADS)

    Cade, William B.; Chan-Park, Christina

    2015-02-01

    Although "space weather" is a fairly recent term, there is a rich history of similar terms being used beginning in the middle to late 1800s. "Solar meteorology," "magnetic weather," and "cosmic meteorology" all appeared during that time frame. The actual first appearance of space weather can be attributed to the publication Science News Letter in 1957 (with the first modern usage in 1959) and was possibly coined by the editor at the time, Watson Davis.

  14. Climate signal and weather noise

    SciTech Connect

    Leith, C.E.

    1995-04-01

    A signal of small climate change in either the real atmosphere or numerical simulation of it tends to be obscured by chaotic weather fluctuations. Time-lagged covariances of such weather processes are used to estimate the sampling errors of time average estimates of climate parameters. Climate sensitivity to changing external influences may also be estimated using the fluctuation dissipation relation of statistical mechanics. Answers to many climate questions could be provided by a realistic stochastic model of weather and climate.

  15. Direct sulfation of limestone based on oxy-fuel combustion technology

    SciTech Connect

    Chen, C.M.; Zhao, C.S.; Liu, S.T.; Wang, C.B.

    2009-10-15

    With limestone as the sorbent, the sulfation reaction can proceed via two different routes depending on whether calcination of the limestone takes place under the given reaction conditions. The direct sulfation reaction is defined as the sulfation reaction between sulfur dioxide (SO{sub 2}) and limestone in an uncalcined state. This reaction, based on oxyfuel combustion technology, was studied by thermogravimetric analysis. Surface morphologies of the limestone particles after sulfation were examined by a scanning electron microscope. Results show that there are more pores or gaps in the product layer formed by direct sulfation of limestone than by indirect sulfation, which can be attributed to the generation of carbon dioxide (CO{sub 2}) at a reaction interface. Compared with indirect sulfation, direct sulfation of limestone can yield much higher conversion and has a much higher reaction rate. For direct sulfation, the greater porosity in the product layer greatly reduces the solid-state ion diffusion distance, resulting in a higher reaction rate and higher conversion.

  16. Influence of limestone characteristics on mercury re-emission in WFGD systems.

    PubMed

    Ochoa-González, Raquel; Díaz-Somoano, Mercedes; Martínez-Tarazona, M Rosa

    2013-03-19

    This work evaluates the influence of the effect of the properties of limestones on their reactivity and the re-emission of mercury under typical wet scrubber conditions. The influence of the composition, particle size, and porosity of limestones on their reactivity and the effect of sorbent concentration, pH, redox potential, and the sulphite and iron content of the slurry on Hg(0) re-emission was assessed. A small particle size, a high porosity and a low magnesium content increased the high reactivity of the limestones. Moreover, it was found that the higher the reactivity of the sample the greater the amount of mercury captured in the scrubber. Although sulphite ions did not cause the re-emission of mercury from the suspensions of the gypsums, the limestones enriched in iron increased Hg(0) re-emission under low oxygen conditions. It was observed that the low pH values of the gypsum suspensions favored the cocapture of mercury because Fe(2+) formation was avoided. The partitioning of the mercury in the byproducts of the scrubber depended on the impurities of the limestones rather than on their particle size. No leaching of mercury from the gypsum samples occurred suggesting that mercury was either tightly bound to the impurities of the limestone or was transformed into insoluble mercury species.

  17. Interpretation of well hydrographs in the karstic Maynardville Limestone at the Oak Ridge Y-12 Plant

    SciTech Connect

    Shevenell, L.A.; McMaster, B.W.

    1996-06-01

    The Maynardville Limestone in Oak Ridge, Tennessee underlies the southern portion of Bear Creek Valley (BCV), and is considered to be the primary pathway for groundwater leaving the Y-12 Plant boundaries. Sixty-seven percent of all wells drilled into the Maynardville Limestone have intersected at least one cavity, suggesting karst features may be encountered throughout the shallow (< 200 ft) portions of the Limestone. Because waste facilities at the Y-12 Plant are located adjacent to the Maynardville Limestone, contaminants could enter the karst aquifer and be transported in the conduit system. As part of an overall hydrologic characterization effort of this karst aquifer, 41 wells in the Maynardville Limestone were instrumented with pressure transducers to monitor water level changes (hydrographs) associated with rain events. Wells at depths between approximately 20 and 750 ft were monitored over the course of at least two storms in order that variations with depth could be identified. The wells selected were not exclusively completed in cavities but were selected to include the broad range of hydrologic conditions present in the Maynardville Limestone. Cavities, fractures and diffuse flow zones were measured at a variety of depths. The water level data from the storms are used to identify areas of quickflow versus slower flowing water zones. The data are also used to estimate specific yields and continuum transmissitives in different portions of the aquifer.

  18. Sedimentology and diagenesis of Miocene Lirio Limestone, Isla de Mona, Puerto Rico

    SciTech Connect

    Ruiz, H.; Gonzalez, L.A.; Budd, A.F. )

    1991-03-01

    Isla de Mona is a carbonate plateau, 50 mi west of Puerto Rico. The island lies on the southern portion of the Mona Platform. It is composed mostly of two Miocene carbonate units: Isla de Mona Dolomite overlain by Lirio Limestone. The Lirio Limestone was deposited on a sloping erosional surface over the Isla de Mona Dolomite. The Miocene Lirio Limestone consists mostly of backreef sands (packstones) with a reefal sequence (boundstones and grainstones) present in the southwestern portion of the island. The reefal sequence is made up mostly of Stylophora, Porites, and Millepora. Thin, discreet pockets of carbonate mud, rich in planktonic foraminifera and radiolarians and mixed with shallow benthic fauna/flora (foraminifera, echinoderms, red algae, and corals) interpreted as storm deposits, are found throughout the unit. An extensive reefal zone can be inferred to be present throughout the southwestern to southern portions of the Mona Platform. The Lirio Limestone is heavily karstified and is riddled with sinkholes on the plateau surfaces and caves around the periphery of the island. Caves are exposed around the periphery of the island, radiating from a depression in the central portions of the Lirio Limestone, near contacts with the Isla de Mona Dolomite, are partially dolomitized. The southwestern outcrops exhibit partial dolomitization throughout. The distribution of sinkholes, seaward caverns, and partial dolomitization of the lowermost Lirio Limestone suggests diagenetic modifications by meteoric fluids in central exposed portions of the island and by marine-meteoric fluids in the lowermost portions of the phreatic lens.

  19. Effects of UV weathering on surface properties of polypropylene composites reinforced with wood flour, lignin, and cellulose

    NASA Astrophysics Data System (ADS)

    Peng, Yao; Liu, Ru; Cao, Jinzhen; Chen, Yu

    2014-10-01

    In this study, the influence of accelerated weathering on polypropylene composites reinforced with wood flour (WF), lignin, and cellulose at different loading levels were evaluated. Six groups of samples were exposed in a QUV accelerated weathering tester for a total of 960 h. The surface color, surface gloss, contact angle and flexural properties of the samples were tested. Besides, the weathered surface was characterized by SEM and ATR-FTIR. The results revealed that (1) the discoloration of composites was accelerated by the presence of lignin, especially at high content; (2) composites containing lignin showed less loss of flexural strength and modulus, less cracks, and better hydrophobicity on weathered surface than other groups, confirming its functions of stabilization and antioxidation; (3) cellulose-based composites exhibited better color stability but more significant deterioration in flexural properties after weathering compared to other composites, suggesting that such kind of composites could not be used as load-bearing structure in outdoor applications.

  20. Space Weathering: An Ultraviolet Indicator

    NASA Technical Reports Server (NTRS)

    Hendrix, A. R.; Vilas, F.

    2003-01-01

    We present evidence suggesting that the spectral slope of airless bodies in the UV-visible wavelength range can be used as an indicator of exposure to space weathering. While space weathering generally produces a reddening of spectra in the visible-NIR spectral regions, it tends to result in a bluing of the UV-visible portion of the spectrum, and may in some cases produce a spectral reversal. The bluing effect may be detectable with smaller amounts of weathering than are necessary to detect the longer-wavelength weathering effects.

  1. Space Weathering: An Ultraviolet Indicator

    NASA Technical Reports Server (NTRS)

    Hendrix, A. R.; Vilas, F.

    2004-01-01

    We present evidence suggesting that the spectral slope of airless bodies in the UV-visible wavelength range can be used as an indicator of exposure to space weathering. While space weathering generally produces a reddening of spectra in the visible-NIR spectral regions, it tends to result in a bluing of the UV-visible portion of the spectrum, and may in some cases produce a spectral reversal. The bluing effect may be detectable with smaller amounts of weathering than are necessary to detect the longer-wavelength weathering effects.

  2. AWE: Aviation Weather Data Visualization

    NASA Technical Reports Server (NTRS)

    Spirkovska, Lilly; Lodha, Suresh K.

    2001-01-01

    The two official sources for aviation weather reports both require the pilot to mentally visualize the provided information. In contrast, our system, Aviation Weather Environment (AWE) presents aviation specific weather available to pilots in an easy to visualize form. We start with a computer-generated textual briefing for a specific area. We map this briefing onto a grid specific to the pilot's route that includes only information relevant to his flight route that includes only information relevant to his flight as defined by route, altitude, true airspeed, and proposed departure time. By modifying various parameters, the pilot can use AWE as a planning tool as well as a weather briefing tool.

  3. Solar weather/climate predictions

    NASA Technical Reports Server (NTRS)

    Schatten, K. H.; Goldberg, R. A.; Mitchell, J. M.; Olson, R.; Schaefer, J.; Silverman, S.; Wilcox, J.; Williams, G.

    1979-01-01

    Solar variability influences upon terrestrial weather and climate are addressed. Both the positive and negative findings are included and specific predictions, areas of further study, and recommendations listed.

  4. Small Sensors for Space Weather

    NASA Astrophysics Data System (ADS)

    Nicholas, A. C.

    2015-12-01

    The Naval Research Laboratory is actively pursuing enhancing the nation's space weather sensing capability. One aspect of this plan is the concept of flying Space Weather sensor suites on host spacecraft as secondary payloads. The emergence and advancement of the CubeSat spacecraft architecture has produced a viable platform for scientifically and operationally relevant Space Weather sensing. This talk will provide an overview of NRL's low size weight and power sensor technologies targeting Space Weather measurements. A summary of on-orbit results of past and current missions will be presented, as well as an overview of future flights that are manifested and potential constellation missions.

  5. Bishop Paiute Weatherization Training Program

    SciTech Connect

    Carlos Hernandez

    2010-01-28

    The DOE Weatherization Training Grant assisted Native American trainees in developing weatherization competencies, creating employment opportunities for Bishop Paiute tribal members in a growing field. The trainees completed all the necessary training and certification requirements and delivered high-quality weatherization services on the Bishop Paiute Reservation. Six tribal members received all three certifications for weatherization; four of the trainees are currently employed. The public benefit includes (1) development of marketable skills by low-income Native individuals, (2) employment for low-income Native individuals in a growing industry, and (3) economic development opportunities that were previously not available to these individuals or the Tribe.

  6. Impact accelerations

    NASA Technical Reports Server (NTRS)

    Vongierke, H. E.; Brinkley, J. W.

    1975-01-01

    The degree to which impact acceleration is an important factor in space flight environments depends primarily upon the technology of capsule landing deceleration and the weight permissible for the associated hardware: parachutes or deceleration rockets, inflatable air bags, or other impact attenuation systems. The problem most specific to space medicine is the potential change of impact tolerance due to reduced bone mass and muscle strength caused by prolonged weightlessness and physical inactivity. Impact hazards, tolerance limits, and human impact tolerance related to space missions are described.

  7. Intelligent Weather Agent

    NASA Technical Reports Server (NTRS)

    Spirkovska, Liljana (Inventor)

    2006-01-01

    Method and system for automatically displaying, visually and/or audibly and/or by an audible alarm signal, relevant weather data for an identified aircraft pilot, when each of a selected subset of measured or estimated aviation situation parameters, corresponding to a given aviation situation, has a value lying in a selected range. Each range for a particular pilot may be a default range, may be entered by the pilot and/or may be automatically determined from experience and may be subsequently edited by the pilot to change a range and to add or delete parameters describing a situation for which a display should be provided. The pilot can also verbally activate an audible display or visual display of selected information by verbal entry of a first command or a second command, respectively, that specifies the information required.

  8. Global weather research

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Modeling, prediction, and analysis of global meteorological phenomena influencing the large scale behavior of the atmosphere are summarized. Prediction of global weather phenomena based on satellite data is discussed and models of global phenomena developed. The atmospheric general circulation model (AGCE) is reviewed, axisymmetric flow calculated, and axisymmetric states in cylindrical, spherical, three dimensional, and spin up numerical models for AGCE described. The role of latent heat release in baroclinic waves, latent heat and cyclonic systems, and a theoretical study of baroclinic flow related to the AGCE and the flow regime were studied with a simplified general circulation model. AGCE and the geophysical fluid flow cell (GFFC) instrumentation are discussed. Investigation of solar and planetary convection for GFFC is described. The utilization of satellite cloud observations to diagnose the energy state and transformations in extratropical cyclones is reviewed.

  9. Nomination of the Globigerina Limestone of the Maltese Islands as a "Global Heritage Stone Resource"

    NASA Astrophysics Data System (ADS)

    Cassar, JoAnn

    2016-04-01

    The Maltese Islands consist of two main islands, Malta and Gozo, as well as a small number of islets, and lie in the central Mediterranean Sea approximately 90 km south of Sicily. Although only 316 square kilometres in size, the Islands contain a rich concentration of archaeological sites and historic buildings, as well as vernacular architecture and modern buildings, for the most part built of the local Globigerina Limestone, which is one of the few natural resources of the Islands. This stone can be described as a typical "soft limestone", very easy to carve and shape. It forms part of the large family of Oligo-Miocene "soft limestones" widely diffused in the Mediterranean Basin. The Maltese Globigerina Limestone Formation is one of five main Formations, and varies in thickness from 20 to over 200 m. The material used for building is located stratigraphically in the lower part of the Globigerina Limestone Formation, called the Lower Globigerina Limestone. This Formation is stratified into thick beds at outcrop. Sections where bioturbation is concentrated often also occur. This limestone is fine-grained, yellow to pale grey in colour, almost wholly composed of the tests of globigerinid planktonic foraminifera. Petrographically, Globigerina Limestone can be described as a bioclastic packstone, with bioclastic wackestones also occurring. This limestone has always been used as the predominant building material in the Islands. The Maltese prehistoric Temples, which were constructed approximately 6000 years ago, bear testimony to this. Between 1530 and 1798 the Order of the Knights of St John built kilometres of fortifications in this same material to protect the Island from the expanding Ottoman Empire. Fortifications, impressive churches, auberges and palaces were built of this stone during this period. The capital city of Valletta, a rich and dense manifestation of Baroque architecture in Globigerina Limestone, is included on the UNESCO World Heritage List, as are

  10. Terminal weather information management

    NASA Technical Reports Server (NTRS)

    Lee, Alfred T.

    1990-01-01

    Since the mid-1960's, microburst/windshear events have caused at least 30 aircraft accidents and incidents and have killed more than 600 people in the United States alone. This study evaluated alternative means of alerting an airline crew to the presence of microburst/windshear events in the terminal area. Of particular interest was the relative effectiveness of conventional and data link ground-to-air transmissions of ground-based radar and low-level windshear sensing information on microburst/windshear avoidance. The Advanced Concepts Flight Simulator located at Ames Research Center was employed in a line oriented simulation of a scheduled round-trip airline flight from Salt Lake City to Denver Stapleton Airport. Actual weather en route and in the terminal area was simulated using recorded data. The microburst/windshear incident of July 11, 1988 was re-created for the Denver area operations. Six experienced airline crews currently flying scheduled routes were employed as test subjects for each of three groups: (1) A baseline group which received alerts via conventional air traffic control (ATC) tower transmissions; (2) An experimental group which received alerts/events displayed visually and aurally in the cockpit six miles (approx. 2 min.) from the microburst event; and (3) An additional experimental group received displayed alerts/events 23 linear miles (approx. 7 min.) from the microburst event. Analyses of crew communications and decision times showed a marked improvement in both situation awareness and decision-making with visually displayed ground-based radar information. Substantial reductions in the variability of decision times among crews in the visual display groups were also found. These findings suggest that crew performance will be enhanced and individual differences among crews due to differences in training and prior experience are significantly reduced by providing real-time, graphic display of terminal weather hazards.

  11. Micro Weather Station

    NASA Technical Reports Server (NTRS)

    Hoenk, Michael E.

    1999-01-01

    Improved in situ meteorological measurements in the troposphere and stratosphere are needed for studies of weather and climate, both as a primary data source and as validation for remote sensing instruments. Following the initial development and successful flight validation of the surface acoustic wave (SAW) hygrometer, the micro weather station program was directed toward the development of an integrated instrument, capable of accurate, in situ profiling of the troposphere, and small enough to fly on a radiosonde balloon for direct comparison with standard radiosondes. On April 23, 1998, working with Frank Schmidlin and Bob Olson of Wallops Island Flight Facility, we flew our instrument in a dual payload experiment, for validation and direct comparison with a Vaisala radiosonde. During that flight, the SAW dewpoint hygrometer measured frostpoint down to -76T at 44,000 feet. Using a laptop computer in radio contact with the balloon, we monitored data in real time, issued the cutdown command, and recovered the payload less than an hour after landing in White Sands Missile Range, 50 miles from the launch site in Hatch, New Mexico. Future flights will extend the intercomparison, and attempt to obtain in situ meteorological profiles from the surface through the tropopause. The SAW hygrometer was successfully deployed on the NASA DC8 as part of NASA's Third Convection and Moisture Experiment (CAMEX-3) during August and September, 1998. This field campaign was devoted to the study of hurricane tracking and intensification using NASA-funded aircraft. In situ humidity data from the SAW hygrometer are currently being analyzed and compared with data from other instruments on the DC8 and ER2 aircraft. Additional information is contained in the original.

  12. Using Forecasting to Teach Weather Science

    NASA Astrophysics Data System (ADS)

    Tsubota, Y.; Takahashi, T.

    2009-09-01

    Weather affects our lives and hence, is a popular topic in daily conversations and in the media. Therefore, it is not only important to teach weather, but is also a good idea to use 'weather' as a topic in science teaching. Science education has two main objectives: to acquire scientific concepts and methods. Weather forecasting is an adequate theme to teach scientific methods because it is dependent on observation. However, it is not easy to forecast weather using only temporal observation. We need to know the tendency of 'weather change' via consecutive and/or continuous weather observation. Students will acquire scientific-observation skills through weather observation. Data-processing skills would be enhanced through a weather-forecasting contest. A contest should be announced within 5 days of school events, such as a school excursion and field day. Students submit their own weather forecast by gathering weather information through the internet, news paper and so on. A weather-forecasting contest compels the student to observe the weather more often. We currently have some different weather forecasts. For example, American weather-related companies such as ACCU weather and Weather Channel provide weather forecast for the many locations all over the world. Comparing these weather forecasting with actual weather, participants such as students could evaluate the differences between forecasted and actual temperatures. Participants will judge the best weather forecast based on the magnitude of the difference. Also, participants evaluate the 'hitting ratio' of each weather forecast. Students can learn elementary statistics by comparing various weather forecasts. We have developed our weather web-site that provides our own weather forecasting and observation. Students acquire science skills using our weather web-site. We will report our lessen plans and explain our weather web-site.

  13. Weather Fundamentals: Hurricanes & Tornadoes. [Videotape].

    ERIC Educational Resources Information Center

    1998

    The videos in this educational series, for grades 4-7, help students understand the science behind weather phenomena through dramatic live-action footage, vivid animated graphics, detailed weather maps, and hands-on experiments. This episode (23 minutes) features information on the deadliest and most destructive storms on Earth. Through satellite…

  14. Now, Here's the Weather Forecast...

    ERIC Educational Resources Information Center

    Richardson, Mathew

    2013-01-01

    The Met Office has a long history of weather forecasting, creating tailored weather forecasts for customers across the world. Based in Exeter, the Met Office is also home to the Met Office Hadley Centre, a world-leading centre for the study of climate change and its potential impacts. Climate information from the Met Office Hadley Centre is used…

  15. FREEZING WEATHER IN PENINSULAR FLORIDA,

    DTIC Science & Technology

    The synoptic situations which bring serious freezing weather to the Florida Peninsula are discussed generally by presenting various weather charts...scheme is presented which might permanently eliminate serious freezing in the Florida Peninsula. Before any solution can be reached, it t necessary to be

  16. Weather to Make a Decision

    ERIC Educational Resources Information Center

    Hoyle, Julie E.; Mjelde, James W.; Litzenberg, Kerry K.

    2006-01-01

    DECIDE is a teacher-friendly, integrated approach designed to stimulate learning by allowing students to make decisions about situations they face in their lives while using scientific weather principles. This learning unit integrates weather science, decision theory, mathematics, statistics, geography, and reading in a context of decision…

  17. Weather Fundamentals: Rain & Snow. [Videotape].

    ERIC Educational Resources Information Center

    1998

    The videos in this educational series, for grades 4-7, help students understand the science behind weather phenomena through dramatic live-action footage, vivid animated graphics, detailed weather maps, and hands-on experiments. This episode (23 minutes) gives concise explanations of the various types of precipitation and describes how the water…

  18. The pioneers of weather forecasting

    NASA Astrophysics Data System (ADS)

    Ballard, Susan

    2016-01-01

    In The Weather Experiment author Peter Moore takes us on a compelling journey through the early history of weather forecasting, bringing to life the personalities, lives and achievements of the men who put in place the building blocks required for forecasts to be possible.

  19. Aviation Weather Information Requirements Study

    NASA Technical Reports Server (NTRS)

    Keel, Byron M.; Stancil, Charles E.; Eckert, Clifford A.; Brown, Susan M.; Gimmestad, Gary G.; Richards, Mark A.; Schaffner, Philip R. (Technical Monitor)

    2000-01-01

    The Aviation Safety Program (AvSP) has as its goal an improvement in aviation safety by a factor of 5 over the next 10 years and a factor of 10 over the next 20 years. Since weather has a big impact on aviation safety and is associated with 30% of all aviation accidents, Weather Accident Prevention (WxAP) is a major element under this program. The Aviation Weather Information (AWIN) Distribution and Presentation project is one of three projects under this element. This report contains the findings of a study conducted by the Georgia Tech Research Institute (GTRI) under the Enhanced Weather Products effort, which is a task under AWIN. The study examines current aviation weather products and there application. The study goes on to identify deficiencies in the current system and to define requirements for aviation weather products that would lead to an increase in safety. The study also provides an overview the current set of sensors applied to the collection of aviation weather information. New, modified, or fused sensor systems are identified which could be applied in improving the current set of weather products and in addressing the deficiencies defined in the report. In addition, the study addresses and recommends possible sensors for inclusion in an electronic pilot reporting (EPIREP) system.

  20. Regional-seasonal weather forecasting

    SciTech Connect

    Abarbanel, H.; Foley, H.; MacDonald, G.; Rothaus, O.; Rudermann, M.; Vesecky, J.

    1980-08-01

    In the interest of allocating heating fuels optimally, the state-of-the-art for seasonal weather forecasting is reviewed. A model using an enormous data base of past weather data is contemplated to improve seasonal forecasts, but present skills do not make that practicable. 90 references. (PSB)

  1. Cohesive model applied to fracture propagation in Indiana Limestone

    NASA Astrophysics Data System (ADS)

    Dewers, T. A.; Rinehart, A. J.; Bishop, J. E.

    2014-12-01

    We apply a cohesive fracture (CF) model to results of short-rod (SR), notched 3-point-bend (N3PB) tests, and Brazil tests in Indiana Limestone. Calibration and validation of the model are performed within a commercial finite element modeling platform. By using a linear traction-displacement softening response for a defined fracture-opening displacement (w1) following peak tensile stress (σcrit), the CF model numerically lumps different spatially distributed inelastic processes occurring at and around fracture tips into a thin zone within an elastic domain. Both the SR and the N3PB test specimen geometries use a notch partway through the sample to control the location of fracture propagation. We develop a mesh for both the SR and N3PB geometries with a narrow cohesive zone in the center of notches. From the Brazil tests, we find a tensile splitting stress (σsplit) of 5.9 MPa. We use a σsplit as the peak tensile stress (σcrit) for all simulations. The Young's modulus (E) and the critical crack opening distance (w1) of the CF model are calibrated against the SR data. The model successfully captures the elastic, yield, peak, and initial and late failure behavior and compares favorably against the N3PB tests. Differences in force-displacement and crack propagation are primarily caused by: more mixed-mode (shear and opening) crack propagation in N3PB than in SR tests, causing a higher peak; and transition from compression (high E) to tension (low E) in a larger volume of the N3PB sample than in the SR geometry. This material is based upon work supported as part of the Center for Frontiers of Subsurface Energy Security, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0001114. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy

  2. Chemical Weathering of Black Shales and Rare Earth Element Composition of Surface Waters and Groundwater

    NASA Astrophysics Data System (ADS)

    Hannigan, R. E.; Johannesson, K. H.

    2001-05-01

    Weathering processes dominate the dissolved and suspended loads of most of the world's major rivers. Among sedimentary rocks, black shales are particularly sensitive to chemical weathering. Therefore, shale systems are useful for investigating the partitioning of chemical elements during chemical weathering. Recent studies, such as those by Peucker-Ehrenbrink, Ravizza and others, link chemical weathering of black shales to changes in marine isotopic composition. Rare earth elements (REE) have a unique chemistry and are ideal for such tracer studies. We explored the effect of modern chemical weathering of black shales on the hydrochemistry of surface and groundwaters in the Mohawk Valley of New York State. This region provides an ideal site for the investigation of trace element remobilization during the chemical weathering of black shales. In this region, surface and groundwaters, in intimate contact with black shales and have high dissolved metal concentrations presumably due to water-rock interactions. The extent to which the dissolved REE composition of the surface and ground waters retains the rock signature is, in someway related to the length of time that the water remains in contact with the rock. We compared the REE compositions of surface and groundwaters in areas draining black shale to those of waters draining regions of dolostone-limestone to explore the extent of metal release due to chemical weathering. Shale normalized REE patterns for stream waters exhibit slight heavy REE enrichments and, at some locations, LREE depletion. REE patterns of the waters normalized to their respective sediments show some LREE depletion. However, waters associated with the Little Falls dolomite show fractionation predominantly enriched in the heavy REEs. Differences between the black shale sites, recorded as light REE depletion and/or middle REE enrichment, may be related to the discharge of the streams and the total dissolved solids. The dissolved REE chemistry of

  3. Weathering instability and landscape evolution

    NASA Astrophysics Data System (ADS)

    Phillips, Jonathan D.

    2005-04-01

    The argument in this paper is that the fundamental control on landscape evolution in erosional landscapes is weathering. The possibility of and evidence for instability in weathering at four scales is examined. The four scales are concerned with weathering processes, allocation of weathered products, the interrelations of weathering and denudation, and the topographic and isostatic responses to weathering-limited denudation (the regolith, hillslope, landscape unit, and landscape scales, respectively). The stability conditions for each model, and the circumstances under which the models themselves are relevant, are used to identify scale-related domains of stability and instability. At the regolith scale, the interactions among weathering rates, resistance, and moisture are unstable, but there are circumstances—over long timescales and where weathering is well advanced—under which the instability is irrelevant. At the hillslope scale, the system is stable when denudation is transport rather than weathering limited and where no renewal of exposure via regolith stripping occurs. At the level of landscape units, the stability model is based entirely on the mutual reinforcements of weathering and erosion. While this should generally lead to instability, the model would be stable where other, external controls of both weathering and erosion rates are stronger than the weathering-erosion feedbacks. At the broadest landscape scale, the inclusion of isostatic responses destabilizes erosion-topography-uplift relationships. Thus, if the spatial or temporal scale is such that isostatic responses are not relevant, the system may be stable. Essentially, instability is prevalent at local spatial scales at all but the longest timescales. Stability at intermediate spatial scales is contingent on whether weathering-erosion feedbacks are strong or weak, with stability being more likely at shorter and less likely at longer timescales. At the broadest spatial scales, instability is

  4. Optimization of Trona/Limestone Injection for SO2 Control in Coal-Fired Boilers

    SciTech Connect

    2005-09-01

    Mobotec USA develops and markets air pollution control systems for utility boilers and other combustion systems. They have a particular interest in technologies that can reduce NOx, SOx, and mercury emissions from coal-fired boilers, and have been investigating the injection of sorbents such as limestone and trona into a boiler to reduce SOx and Hg emissions. WRI proposed to use the Combustion Test Facility (CTF) to enable Mobotec to conduct a thorough evaluation of limestone and trona injection for SO{sub 2} control. The overall goal of the project was to characterize the SO{sub 2} reductions resulting from the injection of limestone and trona into the CTF when fired with a high-sulfur eastern bituminous coal used in one of Mobotec's Midwest installations. Results revealed that when limestone was injected at Ca:S molar ratios of 1.5 to 3.0, the resulting SO{sub 2} reductions were 35-55%. It is believed that further reductions can be attained with improved mixing of the sorbent with the combustion gases. When limestone was added to the coal, at Ca:S molar ratios of 0.5 to 1.5, the SO{sub 2} reductions were 13-21%. The lower reductions were attributed to dead-burning of the sorbent in the high temperature flame zone. In cases where limestone was both injected into the furnace and added to the coal, the total SO{sub 2} reductions for a given Ca:S molar ratio were similar to the reductions for furnace injection only. The injection of trona into the mid-furnace zone, for Na:S molar ratios of 1.4 to 2.4, resulted in SO{sub 2} reductions of 29-43%. Limestone injection did not produce any slag deposits on an ash deposition probe while trona injection resulted in noticeable slag deposition.

  5. Field and laboratory experiments on high dissolution rates of limestone in stream flow

    NASA Astrophysics Data System (ADS)

    Hattanji, Tsuyoshi; Ueda, Mariko; Song, Wonsuh; Ishii, Nobuyuki; Hayakawa, Yuichi S.; Takaya, Yasuhiko; Matsukura, Yukinori

    2014-01-01

    Field and laboratory experiments were performed to examine dissolution rates of limestone in stream flow. Field experiments were conducted in three stream sites (A-C) with different lithological or hydrological settings around a limestone plateau in the Abukuma Mts., Japan. Sites A and B are allogenic streams, which flow from non-limestone sources into dolines, and site C has a karst spring source. Tablets made of limestone from the same plateau with a diameter of 3.5 cm and a thickness of 1 cm were placed in the streams for 3 years (2008-2011) where alkalinity, pH and major cation concentrations were measured periodically. The saturation indices of calcite (SIc) of stream water were - 2.8 ± 0.4 at site A, - 2.5 ± 0.4 at site B and - 0.5 ± 0.4 at site C. Annual weight loss ratios for tablets were extremely high at site A (0.11-0.14 mg cm- 2 d- 1), high at site B (0.05 mg cm- 2 d- 1), and low at site C (0.005 mg cm- 2 d- 1). The contrasting rates of weight loss are mainly explained by chemical conditions of stream water. In addition, laboratory experiments for dissolution of limestone tablets using a flow-through apparatus revealed that flow conditions around the limestone tablet is another important factor for dissolution in the stream environment. These results revealed that limestone dissolves at a rapid rate where water unsaturated to calcite continuously flows, such as in an allogenic stream.

  6. Economic evaluation of limestone and lime flue-gas-desulfurization processes

    SciTech Connect

    Burnett, T.A.; Stephenson, C.D.; Sudhoff, F.A.; Veitch, J.D.

    1983-05-01

    The preliminary-grade economics (accuracy: -15%, +30%) of various alternative limestone scrubbing options (absorber type, with and without forced oxidation, and with and without adipic acid enhancemet) are examined using the current design and economic premises established for the continuing series of economic evaluations performed by TVA for EPA. The economics are projected using the Shawnee lime/limestone computer model, which is based on long-term operating data from the EPA Alkali Scrubbing Test Facility at the TVA Shawnee Steam Plant near Paducah, Kentucky. The capital investment for the base-case limestone scrubbing process (500 MW, 3.5% sulfur coal, 1979 NSPS, spray tower, forced oxidation, landfill) is $206/kW. The first-year and levelized annual revenue requirements are 10.59 and 15.09 mills/kWh, respectively. Costs for the equivalent limestone scrubbing process using a Turbulent Contact Absorber (TCA) are lower while those for the venturi - spray tower absorber are higher. The forced-oxidation landfill disposal option has a lower capital investment than the unoxidized pond disposal option for all cases studied; however, the first-year and levelized annual revenue requirements are slightly higher for the forced-oxidation landfill process for most coal applications. For the spray tower limestone process to achieve a specified SO/sub 2/ removal efficiency, it is more economical to increase the limestone stoichiometry and minimize the absorber L/G. The use of adipic acid or possibly dibasic acid (DBA) as an additive to enhance SO/sub 2/ removal in the limestone scrubbing process is an economically attractive option. The use of adipic acid remains economically attractive even if both a high unit cost and a high degradation factor for adipic acid are assumed. 176 references, 35 figures, 56 tables.

  7. Whole rolled sunflower seeds with or without additional limestone in lactating dairy cattle rations.

    PubMed

    Finn, A M; Clark, A K; Drackley, J K; Schingoethe, D J; Sahlu, T

    1985-04-01

    Thirty lactating Holstein cows were in a continuous trial from 21 to 120 days postpartum to evaluate diets containing whole, rolled sunflower seeds with or without additional limestone. Cows were fed individually total mixed rations of (dry matter) 47% corn silage, 9% alfalfa hay, and 44% concentrate. Concentrates were corn and soybean meal (control); corn, soybean meal, and 22% sunflower seeds; or corn, soybean meal, and sunflower seeds plus 3.5% additional limestone. Milk yield (32.2, 32.0, and 32.8 kg/day) was similar among rations. Yield of 4% fat-corrected milk was lower for cows fed sunflower seeds without additional limestone (30.2, 28.1, and 30.2 kg/day) because of lower milk fat percentages (3.57, 3.19, and 3.51). Milk protein percentage tended to be lower for cows fed sunflower seeds with additional limestone (3.01, 2.97, and 2.90). Milk, flavor score was acceptable but tended to be lower for milk from cows fed sunflower seeds with additional limestone (8.4, 8.5, and 7.9). Milk fat from cows fed sunflower seed rations contained less carbon-14:0, 16:0, and 16:1 fatty acids but more carbon-18:0. Dry matter intakes were 21.0, 18.4, and 20.0 kg/day. Dry matter digestibilities, body weight changes, and ruminal volatile fatty acid concentrations were similar among treatments. Total cholesterol in blood serum was elevated in cows fed sunflower seed rations. Insoluble salts of fatty acids were increased in ruminal fluid dry matter from cows fed sunflower seeds but were not increased further by additional limestone. Concentrations of nonesterified carbon-18:1 fatty acids in ruminal fluid dry matter were lower for cows fed sunflower seeds with additional limestone.

  8. Smooth Sailing for Weather Forecasting

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Through a cooperative venture with NASA's Stennis Space Center, WorldWinds, Inc., developed a unique weather and wave vector map using space-based radar satellite information and traditional weather observations. Called WorldWinds, the product provides accurate, near real-time, high-resolution weather forecasts. It was developed for commercial and scientific users. In addition to weather forecasting, the product's applications include maritime and terrestrial transportation, aviation operations, precision farming, offshore oil and gas operations, and coastal hazard response support. Target commercial markets include the operational maritime and aviation communities, oil and gas providers, and recreational yachting interests. Science applications include global long-term prediction and climate change, land-cover and land-use change, and natural hazard issues. Commercial airlines have expressed interest in the product, as it can provide forecasts over remote areas. WorldWinds, Inc., is currently providing its product to commercial weather outlets.

  9. International Space Weather Initiative (ISWI)

    NASA Technical Reports Server (NTRS)

    Gopalswamy, Nat; Davila, Joseph M.

    2010-01-01

    The International Space Weather Initiative (ISWI) is an international scientific program to understand the external drivers of space weather. The science and applications of space weather has been brought to prominence because of the rapid development of space based technology that is useful for all human beings. The ISWI program has its roots in the successful International Heliophysical Year (IHY) program that ran during 2007 - 2009. The primary objective of the ISWI program is to advance the space weather science by a combination of instrument deployment, analysis and interpretation of space weather data from the deployed instruments in conjunction with space data, and communicate the results to the public and students. Like the IHY, the ISWI will be a grass roots organization with key participation from national coordinators in cooperation with an international steering committee. This talk outlines the ISWI program including its organization and proposed activities.

  10. Upgrade Summer Severe Weather Tool

    NASA Technical Reports Server (NTRS)

    Watson, Leela

    2011-01-01

    The goal of this task was to upgrade to the existing severe weather database by adding observations from the 2010 warm season, update the verification dataset with results from the 2010 warm season, use statistical logistic regression analysis on the database and develop a new forecast tool. The AMU analyzed 7 stability parameters that showed the possibility of providing guidance in forecasting severe weather, calculated verification statistics for the Total Threat Score (TTS), and calculated warm season verification statistics for the 2010 season. The AMU also performed statistical logistic regression analysis on the 22-year severe weather database. The results indicated that the logistic regression equation did not show an increase in skill over the previously developed TTS. The equation showed less accuracy than TTS at predicting severe weather, little ability to distinguish between severe and non-severe weather days, and worse standard categorical accuracy measures and skill scores over TTS.

  11. Accelerator system and method of accelerating particles

    NASA Technical Reports Server (NTRS)

    Wirz, Richard E. (Inventor)

    2010-01-01

    An accelerator system and method that utilize dust as the primary mass flux for generating thrust are provided. The accelerator system can include an accelerator capable of operating in a self-neutralizing mode and having a discharge chamber and at least one ionizer capable of charging dust particles. The system can also include a dust particle feeder that is capable of introducing the dust particles into the accelerator. By applying a pulsed positive and negative charge voltage to the accelerator, the charged dust particles can be accelerated thereby generating thrust and neutralizing the accelerator system.

  12. PV powering a weather station for severe weather

    SciTech Connect

    Young, W. Jr.; Schmidt, J.

    1997-12-31

    A natural disaster, such as Hurricane Andrew, destroys thousands of homes and businesses. The destruction from this storm left thousands of people without communications, potable water, and electrical power. This prompted the Florida Solar Energy Center to study the application of solar electric power for use in disasters. During this same period, volunteers at the Tropical Prediction Center at the National Hurricane Center (NHC), Miami, Florida and the Miami Office of the National Weather Service (NWS) were working to increase the quantity and quality of observations received from home weather stations. Forecasters at NHC have found surface reports from home weather stations a valuable tool in determining the size, strength and course of hurricanes. Home weather stations appear able to record the required information with an adequate level of accuracy. Amateur radio, utilizing the Automatic Packet Report System, (APRS) can be used to transmit this data to weather service offices in virtually real time. Many weather data collecting stations are at remote sites which are not readily serviced by dependable commercial power. Photovoltaic (solar electric) modules generate electricity and when connected to a battery can operate as a stand alone power system. The integration of these components provides an inexpensive standalone system. The system is easy to install, operates automatically and has good communication capabilities. This paper discusses the design criteria, operation, construction and deployment of a prototype solar powered weather station.

  13. Limestones as a paleobathymeter for reconstructing past seismic activities: Muroto-misaki, Shikoku, southwestern Japan

    NASA Astrophysics Data System (ADS)

    Iryu, Y.; Maemoku, H.; Yamada, T.; Maeda, Y.

    2009-03-01

    Muroto-misaki (Cape Muroto) is located at the southern tip of the eastern half of Shikoku, southwestern Japan and is ~ 100 km north of the Nankai Trough where the Philippine Sea Plate is being subducted beneath the Eurasian Plate. Therefore, the Muroto-misaki area has been seismically uplifted. Sedimentologic analyses were conducted on Holocene limestones that occur along the coast from Muroto-misaki to Meoto-iwa, located ~ 13 km north of the cape. The limestones are limited to less than 9.2 m in elevation. The limestones are up to 4.4 m in mean diameter, up to 0.5 m in thickness, and consist mainly of fossilized sessile organisms, including annelids, corals, bryozoans, encrusting foraminifers, barnacles, nongeniculate coralline algae, and, to a lesser extent, molluscs and peyssonneliacean algae. Acicular and equant cements are minor components. Acicular cements are found in semi-closed spaces between coralline algal crusts and their substrates. The modal composition of limestones was determined by a point-counting technique. Based on the biotic composition, the Holocene limestones can be classified into six types (Types I to VI). A comparison of the vertical distribution of these rock types with that of modern sessile organisms indicates that the top of Type I limestone, which is characterized by the occurrence of hermatypic corals, corresponds approximately to the mean low water springs when the limestones formed. A difference in the highest occurrence of Type I limestone between two sites may represent the variation in the total amount of uplift over the last 1000 to 1500 years, which resulted in an apparent northward decline of paleo-mean low water springs at a rate of ~ 10 cm/km. Therefore, the Holocene limestones are a good paleobathymeter to reconstruct past seismic activities in this area. This study shows that warm temperate carbonate deposits are as excellent recorders of geologic events, such as the timing and scale of repeated coseismic uplifts and

  14. Capsule report: Adipic acid-enhanced lime/limestone test results at the EPA alkali scrubbing test facility

    SciTech Connect

    Burbank, D.A.; Wang, S.C.

    1982-04-01

    The fifth in a series of reports describing the results of the Shawnee Lime and Limestone Wet Scrubbing Test Program, the report describes the results of adipic acid-enhanced limestone wet scrubbing systems. A primary objective of the program was to enhance sulfur oxide removal and improve the reliability and economics of lime and limestone wet scrubbing systems by use of adipic acid as a chemical additive.

  15. Tidal rhythmites infine-grained Carboniferous limestones, U.S.A.

    USGS Publications Warehouse

    Archer, A.W.; Feldman, H.R.

    1994-01-01

    Analyses of fine-grained limestones reveals that many exhibit fine-scale laminations. Laminations can be normally graded and consist of a coarser-grained lower part and a finer-grained upper part. The upper part can also contain finely disseminated organic material. Despite the similarities of such graded laminae to yearly varves and turbidites, it can be demonstrated by use of laminae-thickness periodicities that some graded laminae are reasonably interpreted as the product of tidal processes. Within siliciclastic systems, modern analogues of such processes are available for comparisons. In fine-grained facies of the Salem Limestone (Visean; Indiana, U.S.A.), periodicities observed within sequential-laminae thicknesses indicate a dominant control by neap-spring tidal processes. Similarly, laminae within limestones of the vertebrate-bearing Hamilton paleochannel (Stephanian; Kansas, U.S.) exhibit similar features, including fine-scale tidal bundles. This limestone is noted for the abundance of articulated fish fossils. Carbonates containing articulated fish from the Wild Cow Formation (Stephanian; New Mexico, U.S.), exhibit diffuse laminations; however, closely associated siliciclastic mudstones contain laminae that exhibit tidal periodicities. There are many similarities between tidal periodicities and patterns of lamination thicknesses of these rocks. A tidal interpretation for these rocks allows for localized, very rapid rates of deposition. Such rapid deposition may, in part, help to explain how articulated fish and other vertebrates can become preserved within such fine-grained limestones. ?? 1994.

  16. Actinobacterial diversity in limestone deposit sites in Hundung, Manipur (India) and their antimicrobial activities.

    PubMed

    Nimaichand, Salam; Devi, Asem Mipeshwaree; Tamreihao, K; Ningthoujam, Debananda S; Li, Wen-Jun

    2015-01-01

    Studies on actinobacterial diversity in limestone habitats are scarce. This paper reports profiling of actinobacteria isolated from Hundung limestone samples in Manipur, India using ARDRA as the molecular tool for preliminary classification. A total of 137 actinobacteria were clustered into 31 phylotypic groups based on the ARDRA pattern generated and representative of each group was subjected to 16S rRNA gene sequencing. Generic diversity of the limestone isolates consisted of Streptomyces (15 phylotypic groups), Micromonospora (4), Amycolatopsis (3), Arthrobacter (3), Kitasatospora (2), Janibacter (1), Nocardia (1), Pseudonocardia (1) and Rhodococcus (1). Considering the antimicrobial potential of these actinobacteria, 19 showed antimicrobial activities against at least one of the bacterial and candidal test pathogens, while 45 exhibit biocontrol activities against at least one of the rice fungal pathogens. Out of the 137 actinobacterial isolates, 118 were found to have at least one of the three biosynthetic gene clusters (PKS-I, PKS-II, NRPS). The results indicate that 86% of the strains isolated from Hundung limestone deposit sites possessed biosynthetic gene clusters of which 40% exhibited antimicrobial activities. It can, therefore, be concluded that limestone habitat is a promising source for search of novel secondary metabolites.

  17. Stratigraphy and diagenesis of the Mississippian Lodgepole Limestone, Williston Basin, North Dakota

    SciTech Connect

    Grover, P.W. )

    1996-01-01

    Stratigraphic correlation of the Lodgepole Limestone (Bottineau Interval) indicates a sequence of three clinoform-shaped wedges that filled in the early Williston Basin. To date four productive 100m thick mounds have been discovered in the Lodgepole Limestone at Dickinson Field. The mounds seem to have nucleated at the toe of slope of the first highstand system tract and were subsequently buried by the second highstand systems tract. By isopaching each of the systems tracts one can predict were other mounds might have nucleated. Burial depth of the Bakken Shale-Lodgepole Limestone contact grade from 0.6 km at the edge of the Williston Basin to 3.4 km in the center. With increased depth the basal Lodgepole Limestone shows three phases of dolomitization, which are: small clear early dolomite; later iron rich fracture filling saddle dolomite and a later iron rich dolomite that seems to follow stylolites. Pre-oil migration mineralization of the overlying limestone include minor amounts of: anhydrite, pyrite, iron poor sphalerite, late iron rich sphalerite, chalcopyrite and celestite.

  18. Stratigraphy and diagenesis of the Mississippian Lodgepole Limestone, Williston Basin, North Dakota

    SciTech Connect

    Grover, P.W.

    1996-12-31

    Stratigraphic correlation of the Lodgepole Limestone (Bottineau Interval) indicates a sequence of three clinoform-shaped wedges that filled in the early Williston Basin. To date four productive 100m thick mounds have been discovered in the Lodgepole Limestone at Dickinson Field. The mounds seem to have nucleated at the toe of slope of the first highstand system tract and were subsequently buried by the second highstand systems tract. By isopaching each of the systems tracts one can predict were other mounds might have nucleated. Burial depth of the Bakken Shale-Lodgepole Limestone contact grade from 0.6 km at the edge of the Williston Basin to 3.4 km in the center. With increased depth the basal Lodgepole Limestone shows three phases of dolomitization, which are: small clear early dolomite; later iron rich fracture filling saddle dolomite and a later iron rich dolomite that seems to follow stylolites. Pre-oil migration mineralization of the overlying limestone include minor amounts of: anhydrite, pyrite, iron poor sphalerite, late iron rich sphalerite, chalcopyrite and celestite.

  19. Economic evaluation of advanced limestone, Davy S-H, and Dowa Gypsum-producing FGD processes

    SciTech Connect

    Dotson, R.L.; Maxwell, J.D.; Burnett, T.A.

    1984-02-01

    Economic evaluations were made of three gypsum-producing FGD processes: advanced limestone (in-loop forced oxidation with adipic acid additive), Davy S-H (lime), and Dowa (aluminum sulfate, limestone). For a 500-MW power unit burning 3.5% sulfur coal and meeting the 1979 NSPS, capital investments in 1982 costs are 93 M$ (186 $/kW) for the advanced limestone process, 116 M$ (231 $/kW) for the Davy S-H process, and 121 M$ (243 $/kW) for the Dowa process. First-year annual revenue requirements in 1984 costs for these processes are 26, 33, and 32 M$ (9.4, 11.9, and 11.7 mills/kWh), respectively. The lower capital investment and annual revenue requirements of the advanced limestone process is due in part to the use of adipic acid, which allows partial scrubbing at 95% removal. The Davy S-H has slightly higher annual revenue requirements than the Dowa process because lime rather than limestone is used. Changes in power unit size and coal sulfur content affect the costs of all three processes similarly. The Davy S-H process is more sensitive to raw material costs because lime is used. Landfill waste disposal is a minor cost element in all three processes. 103 references, 26 figures, 30 tables.

  20. Effect of magnesium salts on the sulphation capacity of limestone slurry.

    PubMed

    Ozyuğuran, Ayşe; Altun-Ciftçioğlu, Gökçen; Karatepe, Nilgün; Ersoy-Meriçboyu, Ayşegül

    2006-01-01

    The effect of different magnesium salts such as MgO, MgSO(4).7H2O and Mg(OH)2 on the total sulphation capacities of limestone slurries prepared from five different limestone samples was investigated. Sulphation reactions of slurries were conducted at a constant temperature of 323 K in a gaseous mixture consisting of 5% O2, 10% CO2, 0.5% SO2 and a balance of nitrogene by volume. It was found that the total sulphation capacities of limestone slurries increased with the addition of MgO and Mg(OH)2 salts and decreased with the addition of MgSO4.7H2O salt. Depending on the chemical composition of the limestone samples the total sulphation capacities of limestone slurries were increased between 22.30% and 75.00% by MgO addition and between 23.70% and 69.00% by Mg(OH)2 addition.

  1. Fluoride removal from groundwater by limestone treatment in presence of phosphoric acid.

    PubMed

    Gogoi, Sweety; Nath, Suresh K; Bordoloi, Shreemoyee; Dutta, Robin K

    2015-04-01

    Fluoride removal from groundwater has been studied by addition of dilute phosphoric acid (PA) to the influent water before limestone treatment through laboratory plug-flow column experiments and bench-scale plug-flow pilot tests. In this PA-enhanced limestone defluoridation (PAELD) technique, fluoride is removed from 0.526 mM to 0.50-52.60 μM in 3 h with near neutral final pH. The presence of PA increases the fluoride removal capacity of limestone to 1.10 mg/g compared to 0.39 mg/g reported in its absence. The changes in fluoride removal with variation in initial PA concentration, initial fluoride concentration and the final pH have been found to be statistically significant with p < 0.05. The estimated recurring cost is US$ ≈0.58/m(3) water. Simple scrubbing and rinsing is a preferable method for regeneration of limestone as it is almost equally effective with lime or NaOH. Sorption of fluoride by calcium phosphates produced in situ in the reactor is the dominant mechanism of fluoride removal in the PAELD. Precipitation of CaF2 and sorption of fluoride by the limestone also contribute to the fluoride removal. High efficiency, capacity, safety, environment-friendliness, low cost and simplicity of operation make the PAELD a potential technique for rural application.

  2. Effect of magnesium salts on the sulphation capacity of limestone slurry

    SciTech Connect

    Ozyuguran, A.; Altun-Ciftcioglu, G.; Karatepe, N.; Ersoy-Mericboyu, A.

    2006-09-15

    The effect of different magnesium salts such as MgO, MgSO{sub 4}.7H{sub 2}O and Mg(OH){sub 2} on the total sulphation capacities of limestone slurries prepared from five different limestone samples was investigated. Sulphation reactions of slurries were conducted at a constant temperature of 323 K in a gaseous mixture consisting of 5% O{sub 2}, 10% CO{sub 2}, 0.5% SO{sub 2} and a balance of nitrogen by volume. It was found that the total sulphation capacities of limestone slurries increased with the addition of MgO and Mg(OH){sub 2} salts and decreased with the addition of MgSO{sub 4}.7H{sub 2}O salt. Depending on the chemical composition of the limestone samples the total sulphation capacities of limestone slurries were increased between 22.30% and 75.00% by MgO addition and between 23.70% and 69.00% by Mg(OH){sub 2} addition.

  3. Dietary adaptations of Assamese macaques (Macaca assamensis) in limestone forests in Southwest China.

    PubMed

    Huang, Zhonghao; Huang, Chengming; Tang, Chuangbin; Huang, Libin; Tang, Huaxing; Ma, Guangzhi; Zhou, Qihai

    2015-02-01

    Limestone hills are an unusual habitat for primates, prompting them to evolve specific behavioral adaptations to the component karst habitat. From September 2012 to August 2013, we collected data on the diet of one group of Assamese macaques living in limestone forests at Nonggang National Nature Reserve, Guangxi Province, China, using instantaneous scan sampling. Assamese macaques were primarily folivorous, young leaves accounting for 75.5% and mature leaves an additional 1.8% of their diet. In contrast, fruit accounted for only 20.1%. The young leaves of Bonia saxatilis, a shrubby, karst-endemic bamboo that is superabundant in limestone hills, comprised the bulk of the average monthly diet. Moreover, macaques consumed significantly more bamboo leaves during the season when the availability of fruit declined, suggesting that bamboo leaves are an important fallback food for Assamese macaques in limestone forests. In addition, diet composition varied seasonally. The monkeys consumed significantly more fruit and fewer young leaves in the fruit-rich season than in the fruit-lean season. Fruit consumption was positively correlated with fruit availability, indicating that fruit is a preferred food for Assamese macaques. Of seventy-eight food species, only nine contributed >0.5% of the annual diet, and together these nine foods accounted for 90.7% of the annual diet. Our results suggest that bamboo consumption represents a key factor in the Assamese macaque's dietary adaptation to limestone habitat.

  4. Forest seasonality shapes diet of limestone-living rhesus macaques at Nonggang, China.

    PubMed

    Tang, Chuangbin; Huang, Libin; Huang, Zhonghao; Krzton, Ali; Lu, Changhu; Zhou, Qihai

    2016-01-01

    Limestone forests are an unusual habitat for primates, but little information is available for the genus Macaca in such habitats, making a comparative understanding of extant limestone primates' behavioral adaptation incomplete. We collected data on the diet of rhesus macaques (Macaca mulatta) in a limestone habitat at Nonggang Nature Reserve, southwestern Guangxi, China, and examined the effects of forest seasonality on their diet. Our results indicated that a total of 114 species of plants are consumed by macaques. Young leaves are a preferred food, accounting for 48.9 and 56.9% of the overall diets. One group significantly increased young leaf consumption in response to availability. Fruits contributed to only 27.3 and 28.7% of overall diet. The macaque diet varied according to season. They fed on more fruits in the rainy season. Consumption of mature leaves increased when the availability of young leaves and fruits declined in the dry season, indicating that mature leaves are a fallback food for macaques in a limestone habitat. Similar to sympatric Assamese macaques, Bonia saxatilis, a shrubby, karst-endemic bamboo was consumed by rhesus macaques throughout the year, and was the top food species through most of the year, suggesting that bamboo consumption represents a key factor in the macaque's dietary adaptation to limestone habitat.

  5. Limestone dissolution induced by fungal mycelia, acidic materials, and carbonic anhydrase from fungi.

    PubMed

    Li, Wei; Zhou, Peng-Peng; Jia, Li-Ping; Yu, Long-Jiang; Li, Xue-Li; Zhu, Min

    2009-01-01

    Microorganisms influence the dissolution of a number of minerals. Limestone is one of the most abundant rock types in karst areas, and is predominantly calcium carbonate. Two types of experimental systems were designed in this paper, to make comparisons of limestone dissolution rate among the acidic materials and extracellular carbonic anhydrase (CA) excreted by fungi and the enwrapping effect of fungal mycelia. One was the simulated experimental system containing microorganisms. Another was the simulated experimental system without microorganisms. Results of previous experiment indicated that the acidic materials and CA like enzymatic materials excreted by fungi and the enwrapping effect of fungal mycelia were important factors influencing limestone dissolution. In the three factors mentioned above, the dissolution effect was mycelia enwraping effect>acidic dissolution effect>CA enzymatic effect. The results of the second experiment demonstrated further that the limestone dissolution effect of the acidic materials excreted by fungi was stronger than that of CA excreted by fungi. Nevertheless, CA still played an important role in promoting the dissolution of limestone.

  6. Discrimination of reservoir dolostone within tight limestone using rock physics modeling and pre-stack parameters

    NASA Astrophysics Data System (ADS)

    Park, G.; Lee, B.; Lee, G.

    2013-12-01

    Dolostones may be differentiated from limestones based on various pre-stack seismic parameters as they are denser and faster. However, because the seismic properties of a rock are affected strongly by porosity, porous dolostones may not be significantly denser and faster than limestones. We computed various pre-stack parameters (P-impedance, S-impedance, Vp/Vs, Poisson's ratio, Lamé constants) for tight limestones using the Vp and density logs from a well that penetrated Jurassic carbonate and the Vs log, constructed from the empirical relationships of Vp and Vs. The pre-stack parameters of dolostones with 1% - 40% porosity were estimated based on the bulk and shear moduli and bulk densities computed from the formulas proposed by various workers, including Gassmann equations. Crossplots of the pre-stack parameters show that the Lamé constants (λ, μ) are most effective in differentiating dolostones from limestones. In particular, the λρ -μρ vs. μρ crossplot shows a clear-cut separation of the porous dolostones and tight limestones; the porous dolostones plot exclusively to the left of the λρ -μρ of about 25 GPa.

  7. Depositional facies and diagenetic history of Trenton Limestone in northern Indiana

    SciTech Connect

    Fara, D.R.; Keith, B.D.

    1984-12-01

    Subsurface cores were studied petrographically to determine the facies and diagenetic history of the Trenton Limestone on a regional scale in northern Indiana. The Trenton Limestone is a yellowish olive-gray fossiliferous limestone, which is replaced by a light-gray dolostone in northern Indiana. Facies composing the Trenton are: 1) bryozoan-echinoderm packstone, 2) bryozoan-echinoderm grainstone, 3) bryozoan packstone to wackestone, 4) lime mudstone, and 5) dolostone. The bryozoan-echinoderm packstone is the major facies. Coarse-grained (1-4 mm) grainstones are typically 1 ft (30 cm) thick, have abrupt bases, and become muddy upward. They are considered storm deposits. Hardgrounds occur throughout the limestone facies, but they are most numerous toward the base. These facies indicate deposition below wave base, interrupted by periods of high energy during storms. Fossiliferous white and gray chert nodules are scattered throughout the unit. Also found in the limestone facies are prevalent stylolites and microstylolites, an indication of chemical compaction. The dolostone facies consists of coarsely crystalline (0.4 mm) idiotopic dolomite. Pyrite is associated with the dolomite. Porosity, found only in the dolostone, is discontinuous and characterized as intercrystalline, vuggy, and moldic. Porous zones are commonly oil stained or have been plugged by poikilotopic selentic gypsum. Minor amounts of celestite are found as cavity fillings.

  8. Cold-Weather Sports and Your Family

    MedlinePlus

    ... Feeding Your 1- to 2-Year-Old Cold-Weather Sports and Your Family KidsHealth > For Parents > Cold- ... once the weather turns frosty. Beating the Cold-Weather Blahs Once a chill is in the air, ...

  9. AMS-02 as a Space Weather Observatory

    NASA Astrophysics Data System (ADS)

    Whitman, K.; Bindi, V.; Chati, M.; Consolandi, C.; Corti, C.

    2013-12-01

    The Alpha Magnetic Spectrometer (AMS-02) is a state-of-the-art space detector that measures particles in the energy range of hundreds of MeV to a few TeV. AMS-02 has been installed onboard of the International Space Station (ISS) since May 2011 where it will operate for the duration of the station. To date, there is an abundance of space-based solar data collected in the low energy regimes, whereas there are very few direct measurements of higher energy particles available. AMS-02 is capable of measuring arrival time and composition of the highest energy SEPs in space. It is crucial to build a better knowledge base regarding the most energetic and potentially harmful events. We are currently developing a program to employ AMS-02 as a real-time space weather observatory. SEPs with higher energies are usually accelerated during a short period of time and they are the first particles to reach the Earth. AMS-02, measuring these highest energy SEPs, can alert the onset of an SEP event. During the past two years of operation, we have identified two main quantities in AMS-02 that are particularly sensitive to the arrival of SEPs: the detector livetime and the transition radiation detector (TRD) event size. By monitoring the detector livetime and the TRD event size, AMS-02 can pinpoint in real-time the arrival of SEPs inside the Earth's magnetosphere operating as a space weather detector.

  10. Weather Data Receiver

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Northern Video Graphics, Inc. developed a low-cost satellite receiving system for users such as independent meteorologists, agribusiness firms, small airports or flying clubs, marine vessels and small TV stations. Called Video Fax, it is designed for use with certain satellites; the GOES (Geostationary Operational Environmental Satellite) spacecraft operated by the National Oceanic and Atmospheric Administration, the European Space Agency's Meteosat and Japan's Geostationary Meteorological Satellite. By dictum of the World Meteorological Organization, signals from satellites are available to anyone without cost so the Video Fax user can acquire signals directly from the satellite and cut out the middle man, enabling savings. Unit sells for about one-fifth the cost of the equipment used by TV stations. It consists of a two-meter antenna; a receiver; a microprocessor-controlled display computer; and a video monitor. Computer stores data from the satellites and converts it to an image which is displayed on the monitor. Weather map can be preserved as signal data on tape, or it can be stored in a video cassette as a permanent image.

  11. Ultra-accelerated natural sunlight exposure testing

    DOEpatents

    Jorgensen, Gary J.; Bingham, Carl; Goggin, Rita; Lewandowski, Allan A.; Netter, Judy C.

    2000-06-13

    Process and apparatus for providing ultra accelerated natural sunlight exposure testing of samples under controlled weathering without introducing unrealistic failure mechanisms in exposed materials and without breaking reciprocity relationships between flux exposure levels and cumulative dose that includes multiple concurrent levels of temperature and relative humidity at high levels of natural sunlight comprising: a) concentrating solar flux uniformly; b) directing the controlled uniform sunlight onto sample materials in a chamber enclosing multiple concurrent levels of temperature and relative humidity to allow the sample materials to be subjected to accelerated irradiance exposure factors for a sufficient period of time in days to provide a corresponding time of about at least a years worth of representative weathering of the sample materials.

  12. Space weathering on airless bodies

    NASA Astrophysics Data System (ADS)

    Pieters, Carle M.; Noble, Sarah K.

    2016-10-01

    Space weathering refers to alteration that occurs in the space environment with time. Lunar samples, and to some extent meteorites, have provided a benchmark for understanding the processes and products of space weathering. Lunar soils are derived principally from local materials but have accumulated a range of optically active opaque particles (OAOpq) that include nanophase metallic iron on/in rims formed on individual grains (imparting a red slope to visible and near-infrared reflectance) and larger iron particles (which darken across all wavelengths) such as are often found within the interior of recycled grains. Space weathering of other anhydrous silicate bodies, such as Mercury and some asteroids, produces different forms and relative abundance of OAOpq particles depending on the particular environment. If the development of OAOpq particles is minimized (such as at Vesta), contamination by exogenic material and regolith mixing become the dominant space weathering processes. Volatile-rich bodies and those composed of abundant hydrous minerals (dwarf planet Ceres, many dark asteroids, and outer solar system satellites) are affected by space weathering processes differently than the silicate bodies of the inner solar system. However, the space weathering products of these bodies are currently poorly understood and the physics and chemistry of space weathering processes in different environments are areas of active research.

  13. Solar Energetic Particles: Acceleration and Observations

    NASA Astrophysics Data System (ADS)

    Sako, Takashi

    Research of solar energetic particles (SEPs) is important in understanding particle acceleration, transport and interactions taking place in the universe. The importance of space weather to modern human life is also increasing. In this lecture, I introduce a selected subset of SEP observations together with observation techniques and future plans. The aim is to connect these SEP observations with associated particle acceleration mechanisms and the subsequent transport and interaction processes. Because the observational properties are determined by different processes, a wide range of observations is necessary in order to fully understand the phenomena taking place. I will also give an overview of the role of the SEP studies in general astrophysics.

  14. Exploratory and basic fluidized-bed combustion studies. Quarterly report, April-June 1980. [Limestone and dolomite; USA

    SciTech Connect

    Johnson, I.; Myles, K.M.; Swift, W.M.

    1980-12-01

    This work supports the development studies for both atmospheric and pressurized fluidized-bed coal combustion. Laboratory and process development studies are aimed at providing needed information on limestone utilization, removal of particles and alkali metal compounds from the flue gas, control of SO/sub 2/ and trace pollutant emissions, and other aspects of fluidized-bed coal combustion. This report presents information on: (1) the development of a sorbent utilization prediction methodology, (2) studies of factors which affect limestone breakup and elutriation, (3) basic studies of limestone sulfation under combustion conditions, and (4) studies of the kinetics of the hydration of spent limestone.

  15. Porosity development in the Copper Ridge Dolomite and Maynardville Limestone, Bear Creek Valley and Chestnut Ridge, Tennessee

    SciTech Connect

    Goldstrand, P.M.; Menefee, L.S.; Dreier, R.B.

    1995-12-01

    Matrix porosity data from deep core obtained in Bear Creek Valley indicate that porosities in the Maynardville Limestone are lithology and depth dependent. Matrix porosities are greater in the Cooper Ridge Dolomite than in the Maynardville Limestone, yet there is no apparent correlation with depth. Two interrelated diagenetic processes are the major controlling factors on porosity development in the Copper Ridge Dolomite and Maynardville Limestone; dissolution of evaporate minerals and dedolomitization. Both of these diagenetic processes produce matrix porosities between 2.1 and 1.3% in the Copper Ridge Dolomite and upper part of the Maynardville Limestone (Zone 6) to depths of approximately 600 ft bgs. Mean matrix porosities in Zones 5 through 2 of the Maynardville Limestone range from 0.8 to 0.5%. A large number of cavities have been intersected during drilling activities in nearly all zones of the Maynardville Limestone in Bear Creek Valley. Therefore, any maynardville Limestone zone within approximately 200 ft of the ground surface is likely to contain cavities that allow significant and rapid flow of groundwater. Zone 6 could be an important stratigraphic unit in the Maynardville Limestone for groundwater flow and contaminant transport because of the abundance of vuggy and moldic porosities. There are large variations in the thickness and lithology in the lower part of the Maynardville (Zones 2, 3, and 4 in the Burial Grounds region). The direction and velocity of strike-parallel groundwater flow may be altered in this area within the lower Maynardville Limestone.

  16. Acceleration modules in linear induction accelerators

    NASA Astrophysics Data System (ADS)

    Wang, Shao-Heng; Deng, Jian-Jun

    2014-05-01

    The Linear Induction Accelerator (LIA) is a unique type of accelerator that is capable of accelerating kilo-Ampere charged particle current to tens of MeV energy. The present development of LIA in MHz bursting mode and the successful application into a synchrotron have broadened LIA's usage scope. Although the transformer model is widely used to explain the acceleration mechanism of LIAs, it is not appropriate to consider the induction electric field as the field which accelerates charged particles for many modern LIAs. We have examined the transition of the magnetic cores' functions during the LIA acceleration modules' evolution, distinguished transformer type and transmission line type LIA acceleration modules, and re-considered several related issues based on transmission line type LIA acceleration module. This clarified understanding should help in the further development and design of LIA acceleration modules.

  17. GEM: Statistical weather forecasting procedure

    NASA Technical Reports Server (NTRS)

    Miller, R. G.

    1983-01-01

    The objective of the Generalized Exponential Markov (GEM) Program was to develop a weather forecast guidance system that would: predict between 0 to 6 hours all elements in the airways observations; respond instantly to the latest observed conditions of the surface weather; process these observations at local sites on minicomputing equipment; exceed the accuracy of current persistence predictions at the shortest prediction of one hour and beyond; exceed the accuracy of current forecast model output statistics inside eight hours; and be capable of making predictions at one location for all locations where weather information is available.

  18. Stormy weather in galaxy clusters

    PubMed

    Burns

    1998-04-17

    Recent x-ray, optical, and radio observations coupled with particle and gas dynamics numerical simulations reveal an unexpectedly complex environment within clusters of galaxies, driven by ongoing accretion of matter from large-scale supercluster filaments. Mergers between clusters and continuous infall of dark matter and baryons from the cluster periphery produce long-lived "stormy weather" within the gaseous cluster atmosphere-shocks, turbulence, and winds of more than 1000 kilometers per second. This weather may be responsible for shaping a rich variety of extended radio sources, which in turn act as "barometers" and "anemometers" of cluster weather.

  19. Space Weather Forecasting: An Enigma

    NASA Astrophysics Data System (ADS)

    Sojka, J. J.

    2012-12-01

    The space age began in earnest on October 4, 1957 with the launch of Sputnik 1 and was fuelled for over a decade by very strong national societal concerns. Prior to this single event the adverse effects of space weather had been registered on telegraph lines as well as interference on early WWII radar systems, while for countless eons the beauty of space weather as mid-latitude auroral displays were much appreciated. These prior space weather impacts were in themselves only a low-level science puzzle pursued by a few dedicated researchers. The technology boost and innovation that the post Sputnik era generated has almost single handedly defined our present day societal technology infrastructure. During the decade following Neil's walk on the moon on July 21, 1969 an international thrust to understand the science of space, and its weather, was in progress. However, the search for scientific understand was parsed into independent "stove pipe" categories: The ionosphere-aeronomy, the magnetosphere, the heliosphere-sun. The present day scientific infrastructure of funding agencies, learned societies, and international organizations are still hampered by these 1960's logical divisions which today are outdated in the pursuit of understanding space weather. As this era of intensive and well funded scientific research progressed so did societies innovative uses for space technologies and space "spin-offs". Well over a decade ago leaders in technology, science, and the military realized that there was indeed an adverse side to space weather that with each passing year became more severe. In 1994 several U.S. agencies established the National Space Weather Program (NSWP) to focus scientific attention on the system wide issue of the adverse effects of space weather on society and its technologies. Indeed for the past two decades a significant fraction of the scientific community has actively engaged in understanding space weather and hence crossing the "stove

  20. Assessment of the weathering of protective coatings using x-ray photoelectron spectroscopy

    SciTech Connect

    Wilson, G.R.; Skerry, B.S.

    1993-12-31

    Three fully formulated coatings systems: polyurethane, alkyd and latex, were exposed either outdoors to a natural industrial atmospheric environment or to an accelerated corrosion/weathering test incorporating UV-condensation exposures and wet/dry corrosion cycling or to an RF generated {open_quotes}in-glow{close_quotes} oxygen plasma. Changes in coating surface chemistry as a function of time in each environment were followed using X-ray photoelectron spectroscopy (XPS). XPS detected changes in the surface composition of all three systems for all three environmentS. Some of the trends in degradation detected on the exterior exposed samples were reproduced by both accelerated tests. The data obtained from this study also suggested that the corrosion/weathering test would benefit from an increase in the amount of UV exposure over that which is currently used. Oxygen plasma etching also appears to have some potential as a tool for accelerated weathering of paint systems.

  1. Energy, Weatherization and Indoor Air Quality

    EPA Pesticide Factsheets

    Climate change presents many challenges, including the production of severe weather events. These events and efforts to minimize their effects through weatherization can adversely affect indoor environments.

  2. Compute the Weather in Your Classroom.

    ERIC Educational Resources Information Center

    Meier, Beverly

    1988-01-01

    Discusses a weather prediction activity connecting local weather network by computer modem. Describes software for telecommunications, data gathering, preparation work, and instructional procedures. (YP)

  3. STEREO Space Weather and the Space Weather Beacon

    NASA Technical Reports Server (NTRS)

    Biesecker, D. A.; Webb, D F.; SaintCyr, O. C.

    2007-01-01

    The Solar Terrestrial Relations Observatory (STEREO) is first and foremost a solar and interplanetary research mission, with one of the natural applications being in the area of space weather. The obvious potential for space weather applications is so great that NOAA has worked to incorporate the real-time data into their forecast center as much as possible. A subset of the STEREO data will be continuously downlinked in a real-time broadcast mode, called the Space Weather Beacon. Within the research community there has been considerable interest in conducting space weather related research with STEREO. Some of this research is geared towards making an immediate impact while other work is still very much in the research domain. There are many areas where STEREO might contribute and we cannot predict where all the successes will come. Here we discuss how STEREO will contribute to space weather and many of the specific research projects proposed to address STEREO space weather issues. We also discuss some specific uses of the STEREO data in the NOAA Space Environment Center.

  4. Response of the soil physical properties to restoration techniques in limestone quarries

    NASA Astrophysics Data System (ADS)

    Luna Ramos, Lourdes; Miralles Mellado, Isabel; Vignozzi, Nadia; Solé-Benet, Albert

    2016-04-01

    The devastating effects of soil erosion in mining areas from arid/semiarid environments have prompted efforts geared toward an improvement of the soil physical conditions for a fast establishment of vegetal cover. Restoration practices that increase soil moisture content are essential in drylands where rainfall is irregular or insufficient in order to accelerate ecological restoration. The aim of this study was to analyse the influence of organic amendments and mulches on the soil porosity as well as their impact on infiltration, five years after the beginning of an experimental restoration from limestone quarries in Sierra de Gádor (Almería, SE Spain). Nine plots 15 x 5 m were prepared at the site in a completely randomized 2 x 3 factorial design. The first factor, organic amendment, had three levels: sewage sludge (SA), compost from domestic organic residues (CA) and no amendment (NA). The second factor, mulches, also had three levels: gravel (GM), woodchip (WM) and no mulch (NM). In each experimental plot 75 native plants (Macrochloa tenacissima, Anthyllis terniflora and Anthyllis cytisoides) were planted. Infiltration was determined from rainfall simulations and soil porosity was assessed by image analysis of soil thin sections. Total porosity and pores distribution were measured according to pore shape (regular, irregular and elongated) and size (transmission pores [50-500 μm] and fissures [>500 μm]). Natural undisturbed soils around the mine area were used as a reference soil (RS). Restoration treatments showed higher total porosity, fissures and elongated pores than RS and we observed the highest values in treatments with WM. This fact is due to the disruption caused by the application of treatments rather that a good soil structure. Each combination exhibited different values of transmission pores, being greater in the combinations of NA-GM, SA-NM and CA-WM. Infiltration increased with the increase of the total porosity, fissures and elongated pores

  5. Prediction of building limestone physical and mechanical properties by means of ultrasonic P-wave velocity.

    PubMed

    Concu, Giovanna; De Nicolo, Barbara; Valdes, Monica

    2014-01-01

    The aim of this study was to evaluate ultrasonic P-wave velocity as a feature for predicting some physical and mechanical properties that describe the behavior of local building limestone. To this end, both ultrasonic testing and compressive tests were carried out on several limestone specimens and statistical correlation between ultrasonic velocity and density, compressive strength, and modulus of elasticity was studied. The effectiveness of ultrasonic velocity was evaluated by regression, with the aim of observing the coefficient of determination r(2) between ultrasonic velocity and the aforementioned parameters, and the mathematical expressions of the correlations were found and discussed. The strong relations that were established between ultrasonic velocity and limestone properties indicate that these parameters can be reasonably estimated by means of this nondestructive parameter. This may be of great value in a preliminary phase of the diagnosis and inspection of stone masonry conditions, especially when the possibility of sampling material cores is reduced.

  6. Microfacies and diagenesis of Gua Bama limestone, Pahang Darul Makmur, Malaysia

    NASA Astrophysics Data System (ADS)

    Joeharry, Nelisa Ameera Mohamed; Ali, Che Aziz; Leman, Mohd Shafeea; Mohamed, Kamal Roslan

    2016-11-01

    Gua Bama limestone hill in Lipis District, Pahang State is a well-known site for the hunt of Malaysian Permo-Triassic Boundary. This paper details the microfacies and diagenesis of limestone succession at Gua Bama outcrop as an early effort to constrain the desired Permo-Triassic Boundary. Six microfacies have been identified: mudstone, peloidal wackestone, bioclastic wackestone, radiolarian wackestone, intraclastic packstone, and peloidal packstone. The appearance of highly diverse benthic fauna in fragmented forms and the dominance of mudstone-wackestone microfacies prove that carbonates of Gua Bama were deposited in low-energy shallow marine environment. Gua Bama have been subjected to multiple diagenetic processes, namely cementation, compaction, neomorphism, and micritization. Based on diagenetic textures observed, it can be interpreted that Gua Bama limestone had undergone diagenesis within marine water phreatic zone and deep burial realms.

  7. Stratigraphy and depositional history of the Iola Limestone Upper Pennsylvanian (Missourian), Northern Midcontinent U.S.

    NASA Astrophysics Data System (ADS)

    Mitchell, J. C.

    The Iola Limestone, one of the best developed and most laterally extensive, yet least studied Missourian cyclic carbonates in the Midcontinent Upper Pennsylvanian, was studied. Along with adjacent shales, five members constitute the Iola cyclothem, a typical Kansas cyclothem. In ascending order these are: Chanute Shale; Paola Limestone; Munice Creek Shale; Raytown Limestone; and Lane/Bonner Springs Shale. Although traditional interpretation of cyclothems regarded all shale as nearshore, shallow-water deposits, Iola lithology and stratigraphy support the more recent hypothesis that the cyclothem represents a single transgressive-regressive event, with maximum transgression occurring during deposition of the Muncie Creek Shale. Distribution of conodonts reflects the depositional pattern of the Iola cyclothem. Vertical variation far outweighs lateral variation in abundance and diversity.

  8. Reduction of soil pollution by usingwaste of the limestone in the cement industry

    NASA Astrophysics Data System (ADS)

    Muñoz, M. Cecilia Soto; Robles Castillo, Marcelo; Blanco Fernandez, David; Diaz Gonzalez, Marcos; Naranjo Lamilla, Pedro; Moore Undurraga, Fernando; Pardo Fabregat, Francisco; Vidal, Manuel Miguel Jordan; Bech, Jaume; Roca, Nuria

    2016-04-01

    In the cement manufacturing process (wet) a residue is generated in the flotation process. This builds up causing contamination of soil, groundwater and agricultural land unusable type. In this study to reduce soil and water pollution 10% of the dose of cement was replaced by waste of origin limestone. Concretes were produced with 3 doses of cement and mechanical strengths of each type of concrete to 7, 28 and 90 days were determined. the results indicate that the characteristics of calcareous residue can replace up to 10% of the dose of cement without significant decreases in strength occurs. It is noted that use of the residue reduces the initial resistance, so that the dose of cement should not be less than 200 kg of cement per m3. The results allow recommends the use of limestone waste since it has been observed decrease in soil and water contamination without prejudice construction material Keywords: Soil contamination; Limestone residue; Adding concrete

  9. Water resources of the Edwards limestone in the San Antonio area, Texas

    USGS Publications Warehouse

    Livingston, Penn; Sayre, A.N.; White, W.N.

    1936-01-01

    The water enters the limestone in a zone of outcrop along the Balcones escarpment, which crosses the northern parts of Bexar and Medina Counties and extends a long distance both to the east and west of these counties. It is estimated that the combined annual losses into the limestone from the Medina, Prio, Dry Prio, Nueces, and Sabinal Rivers and Hondo Creek may average as much as 150,000 acre-feet a year, the equivalent of a continuous flow of about 134,000,000 gallons a day. Smaller streams also contribute to the underground reservoir, and additional recharge is provided from rainfall on the outcrop of the limestone by direct penetration and by seepage from innumerable storm-water channels.

  10. Prediction of Building Limestone Physical and Mechanical Properties by Means of Ultrasonic P-Wave Velocity

    PubMed Central

    Concu, Giovanna; De Nicolo, Barbara; Valdes, Monica

    2014-01-01

    The aim of this study was to evaluate ultrasonic P-wave velocity as a feature for predicting some physical and mechanical properties that describe the behavior of local building limestone. To this end, both ultrasonic testing and compressive tests were carried out on several limestone specimens and statistical correlation between ultrasonic velocity and density, compressive strength, and modulus of elasticity was studied. The effectiveness of ultrasonic velocity was evaluated by regression, with the aim of observing the coefficient of determination r2 between ultrasonic velocity and the aforementioned parameters, and the mathematical expressions of the correlations were found and discussed. The strong relations that were established between ultrasonic velocity and limestone properties indicate that these parameters can be reasonably estimated by means of this nondestructive parameter. This may be of great value in a preliminary phase of the diagnosis and inspection of stone masonry conditions, especially when the possibility of sampling material cores is reduced. PMID:24511286

  11. Transport mechanisms and genesis of limestone clast conglomerates with examples from Cambrian of east Tennessee

    SciTech Connect

    Kozar, M.G.; Weber, L.J.; Walker, K.R.

    1986-05-01

    Limestone clast conglomerates are common sedimentary features of most Cambrian strata. Cambrian researchers have considered many of these conglomeratic deposits to have formed from erosion and redeposition of partially lithified sediments by storm currents in shallow subtidal and intertidal environments. Analysis of conglomeratic beds from the Middle and Late Cambrian (Maryville Limestone and Nolichucky Shale) in east Tennessee suggests that other, more dominant, processes were responsible for their genesis and transport. The proposed processes may serve as an alternative explanation for limestone clast conglomerates deposited elsewhere in Cambrian sequences. As the authors gain a greater understanding of transport mechanisms and their resultant sedimentary features, many of the conglomeratic beds that were once thought to be the result of storms may be reinterpreted as mass-gravity flows. Differentiating between these various types of transport mechanisms may be crucial to paleo-environmental interpretation.

  12. Franciscan complex calera limestones: Accreted remnants of farallon plate oceanic plateaus

    USGS Publications Warehouse

    Tarduno, J.A.; McWilliams, M.; Debiche, M.G.; Sliter, W.V.; Blake, M.C.

    1985-01-01

    The Calera Limestone, part of the Franciscan Complex of northern California, may have formed in a palaeoenvironment similar to Hess and Shatsky Rises of the present north-west Pacific1. We report here new palaeomagnetic results, palaeontological data and recent plate-motion models that reinforce this assertion. The Calera Limestone may have formed on Farallon Plate plateaus, north of the Pacific-Farallon spreading centre as a counterpart to Hess or Shatsky Rises. In one model2, the plateaus were formed by hotspots close to the Farallon_Pacific ridge axis. On accretion to North America, plateau dissection in the late Cretaceous to Eocene (50-70 Myr) could explain the occurrence of large volumes of pillow basalt and exotic blocks of limestone in the Franciscan Complex. Partial subduction of the plateaus could have contributed to Laramide (70-40 Myr) compressional events3. ?? 1985 Nature Publishing Group.

  13. Optimization of limestone sizing for CFB combustors: Results of pilot plant and bench-scale testing

    SciTech Connect

    Alliston, M.; Edvardsson, C.; Wu, S.; Probst, S.

    1994-12-31

    A grant to study the performance of limestones in a Circulating Fluidized Bed Combustor was obtained in 1991 from the Pennsylvania Energy Development Authority (PEDA) by Tampella Power Corporation (TPC). The overall objective of this PEDA project was to carry out a systematic pilot plant tests at TPC`s pilot plant in Williamsport, Pennsylvania, in systematic order to identify ways of improving sulfur capture and limestone utilization through better control of the size distribution and residence time of the limestone particles in the furnace. It was also an objective to determine if bench scale testing could be of value in predicting CFB sorbent behavior. The pilot plant and bench test results were incorporated into an empirical Correlation which accounts for the size distribution and residence time of solids in CFB boiler.

  14. Freshwater biodissolution rates of limestone in the temperate climate of the Dinaric karst in Slovenia

    NASA Astrophysics Data System (ADS)

    Mulec, J.; Prelovšek, M.

    2015-01-01

    Dissolution rates in two freshwater karst systems were determined by using tablets of dense micrite-biopelmicrite Cretaceous limestone. Submerged limestone tablets in riverbeds were subjected to a natural gradient from complete darkness to direct sunlight. Higher light rates significantly (p < 0.05) increased the epilithic biomass of phototrophs and the overall dissolution rates, which were highest at the Unica spring (- 49.2 μm a- 1), but the exact portion of light-dependent dissolution remains elusive. In the karst river Unica, with its big fluctuations in environmental parameters (e.g., discharge), light rates can be used in estimating the dissolution rates enhanced by phototrophs. Natural biofilms in aquatic systems have important implications for landform evolution, and the impact on limestone dissolution rates is comparable with rates of debris falling from steep slopes.

  15. Weight losses of marble and limestone briquettes exposed to outdoor environments in the eastern United States

    SciTech Connect

    Reimann, K.J.

    1991-09-01

    Gravimetric changes in marble and limestone briquettes exposed to outdoor environment at five sites in the eastern United States have been monitored since 1984. An earlier report describes procedures and results obtained in 1984--1988. This report presents the results of the exposure period 1984--1988 and reviews and summarizes those of prior years. A linear relationship was found between cumulative gravimetric losses and exposure period or rain depth. These losses resulted in an average recession rate of 14 to 24 {mu}m/yr for marble and twice that for limestone. Variations in recession among the various exposure sites can be ascribed to differences in rain depth and hydrogen ion concentration. The annual recession rates obtained from gravimetry yielded rates that were for marble twice those obtained from runoff experiments, and more than three times those for limestone; this indicates that physical erosion plays an important role. Gravimetric monitoring of exposed briquettes is continuing in a planned 10-yr program.

  16. Effects of magnesium and chloride ions on limestone dual-alkali-system performance

    SciTech Connect

    Chang, J.C.S.; Kaplan, N.; Brna, T.G.

    1985-08-01

    The paper gives results of pilot plant tests to evaluate the effects of magnesium and chloride ions on system performance of limestone-regenerated dual alkali processes under closed-loop operating conditions. It was found that limestone reactivity and solids dewatering properties are very sensitive to magnesium ion concentrations. The total magnesium ion concentration should be maintained below 1000 ppm for satisfactory performance under normal operation. A model which assumes competitive surface adsorption of calcium and magnesium ions was used to interpret the data. Limestone reactivity and solids dewatering properties decreased with the increase of chloride ion concentrations; however, the effect of chloride ion accumulation was not significant until the concentration reached 80,000 ppm.

  17. Thermochemical degradation of limestone aggregate concrete on exposure to sodium fire

    NASA Astrophysics Data System (ADS)

    Premila, M.; Sivasubramanian, K.; Amarendra, G.; Sundar, C. S.

    2008-04-01

    Limestone aggregate concrete blocks were subjected to sodium fire conforming to a realistic scenario in order to qualify them as protective sacrificial layers over structural concrete flooring in liquid metal-cooled fast breeder reactors. Mid infrared absorption measurements were carried out on these sodium fire-exposed samples as a function of depth from the affected surface. Definite signatures of thermochemical degradation indicating dehydration and structural modification of the limestone concrete have been obtained. Control runs were carried out to delineate the thermal effects of sodium fires from that of the chemical interaction effects. Measurements on limestone aggregate samples treated with fused NaOH provided direct evidence of the exact mechanism of the sodium attack on concrete. The observed degradation effects were correlated to the mechanical strength of the concrete blocks and to the intensity of the sodium fire experienced.

  18. Weather-Related Mortality

    PubMed Central

    Anderson, Brooke G.; Bell, Michelle L.

    2012-01-01

    Background Many studies have linked weather to mortality; however, role of such critical factors as regional variation, susceptible populations, and acclimatization remain unresolved. Methods We applied time-series models to 107 US communities allowing a nonlinear relationship between temperature and mortality by using a 14-year dataset. Second-stage analysis was used to relate cold, heat, and heat wave effect estimates to community-specific variables. We considered exposure timeframe, susceptibility, age, cause of death, and confounding from pollutants. Heat waves were modeled with varying intensity and duration. Results Heat-related mortality was most associated with a shorter lag (average of same day and previous day), with an overall increase of 3.0% (95% posterior interval: 2.4%–3.6%) in mortality risk comparing the 99th and 90th percentile temperatures for the community. Cold-related mortality was most associated with a longer lag (average of current day up to 25 days previous), with a 4.2% (3.2%–5.3%) increase in risk comparing the first and 10th percentile temperatures for the community. Mortality risk increased with the intensity or duration of heat waves. Spatial heterogeneity in effects indicates that weather–mortality relationships from 1 community may not be applicable in another. Larger spatial heterogeneity for absolute temperature estimates (comparing risk at specific temperatures) than for relative temperature estimates (comparing risk at community-specific temperature percentiles) provides evidence for acclimatization. We identified susceptibility based on age, socioeconomic conditions, urbanicity, and central air conditioning. Conclusions Acclimatization, individual susceptibility, and community characteristics all affect heat-related effects on mortality. PMID:19194300

  19. Titan's Exotic Weather

    NASA Astrophysics Data System (ADS)

    Griffith, Caitlin A.

    2006-09-01

    Images of Titan, taken during the joint NASA and European Space Agency Cassini-Huygens mission, invoke a feeling of familiarity: washes wind downhill to damp lakebeds; massive cumuli form and quickly dissipate, suggestive of rain; and dark oval regions resemble lakes. These features arise from Titan's unique similarity with Earth: both cycle liquid between their surfaces and atmospheres, but in Titan's cool atmosphere it is methane that exists as a gas, liquid, and ice. While Titan enticingly resembles Earth, its atmosphere is 10 times thicker, so that its radiative time constant near the surface exceeds a Titan year, and prohibits large thermal gradients and seasonal surface temperature variations exceeding 3K. Titan also lacks oceans - central to Earth's climate - and instead stores much of its condensible in its atmosphere. As a result, Titan's weather differs remarkably from Earth's. Evidence for this difference appears in the location of Titan's large clouds, which frequent a narrow band at 40S latitude and a region within 30 latitude of the S. Pole. Ground-based and Cassini observations, combined with thermodynamic considerations, indicate that we are seeing large convective cloud systems. Detailed cloud models and general circulation models further suggest that these are severe rain storms, which will migrate with the change in season. Outside these migrating "gypsy" cloud bands, the atmosphere appears to be calm, humid and thus frequented by thin stratiform clouds. An intriguingly alien environment is predicted. Yet, the combined effects of Titan's patchy wet surface, atmospheric tides, possible ice volcanoes, and detailed seasonal variations remain unclear as we have witnessed only one season so far. This talk will review observations of Titan's lower atmosphere and modeling efforts to explain the observations, and explore the questions that still elude us.

  20. Investigations of a Cretaceous limestone with spectral induced polarization and scanning electron microscopy

    NASA Astrophysics Data System (ADS)

    Johansson, Sara; Sparrenbom, Charlotte; Fiandaca, Gianluca; Lindskog, Anders; Olsson, Per-Ivar; Dahlin, Torleif; Rosqvist, Håkan

    2016-11-01

    Characterization of varying bedrock properties is a common need in various contexts, ranging from large infrastructure pre-investigations to environmental protection. A direct current resistivity and time domain induced polarization (IP) survey aiming to characterize properties of a Cretaceous limestone was carried out in the Kristianstad basin, Sweden. The time domain IP data was processed with a recently developed method in order to suppress noise from the challenging urban setting in the survey area. The processing also enabled extraction of early decay times resulting in broader spectra of the time decays and inversion for Cole-Cole parameters. The aim of this study is to evaluate the usefulness of Cole-Cole inverted IP data in early time ranges for bedrock characterization. The inverted sections showed variations within the limestone that are probably caused by variations in texture and composition. Samples from a deep drilling in the Kristianstad basin were investigated with scanning electron microscopy and energy dispersive X-ray spectroscopy, and the results showed that varying amounts of pyrite, glauconite and clay matrix were present at different levels in the limestone. The local high IP anomalies in the limestone could be caused by these minerals otherwise the IP responses were generally weak. There were also differences in the texture of the limestone at different levels, governed by fossil shapes and composition, proportions of calcareous cement and matrix as well as amount of silicate grains. Textural variations may have implications on the variation in Cole-Cole relaxation time and frequency factor. However, more research is needed in order to directly connect microgeometrical properties in limestone to spectral IP responses. The results from this study show that it is possible to recover useable spectral information from early decay times. We also show that under certain conditions (e.g. relatively short relaxation times in the subsurface), it is

  1. Magnetic characterization using a three-dimensional hysteresis projection, illustrated with a study of limestones

    NASA Astrophysics Data System (ADS)

    Borradaile, Graham J.; Lagroix, France

    2000-04-01

    Limestones provide an important source of palaeomagnetic information despite their low content of submicroscopic remanence-bearing minerals. The chief sources of these minerals are thought to be clastic volcanic magnetite and titanomagnetite, and organic magnetite, the latter mostly from bacterial sources. Chemically remagnetized limestones carry magnetite or pyrrhotite. Three hysteresis properties prove useful in identifying and characterizing these mineralogical influences on limestones: the ratio of zero-field maximum remanence to saturation remanence (Mr/Ms) in an applied field, coercivity of remanence (Bcr) and coercivity (Bc). To a lesser extent Kf/Ms may be useful, where Kf is the ferrimagnetic susceptibility. Traditionally, these have been plotted on a combination of 2-D graphs that of necessity only preserve two variables (Day et al. 1977; Wasilewski 1973). However, we found that magnetic discrimination and characterization of the limestones was much easier on a three-axis hysteresis projection that preserves the values of Bcr, Bc and Mr/Ms as independent variables. Using logarithmic scales, the regression surfaces through the data become almost planar and distinguish pelagic, shallow marine, shelf and remagnetized limestones on the basis of the slope and intercept of the associated regression surface. Clearly, there are sensitive sedimentological, geochemical or organic influences that dictate the magnetic mineralogy through sedimentary environment. Moreover, the 3-D plot of hysteresis criteria affords easy recognition of remagnetized limestones and may permit the rejection of material unsuitable for palaeomagnetic study. The 3-D hysteresis projection may be useful for the characterization of other rocks and magnetic materials

  2. Progress on plasma accelerators

    SciTech Connect

    Chen, P.

    1986-05-01

    Several plasma accelerator concepts are reviewed, with emphasis on the Plasma Beat Wave Accelerator (PBWA) and the Plasma Wake Field Accelerator (PWFA). Various accelerator physics issues regarding these schemes are discussed, and numerical examples on laboratory scale experiments are given. The efficiency of plasma accelerators is then revealed with suggestions on improvements. Sources that cause emittance growth are discussed briefly.

  3. Practical Weathering for Geology Students.

    ERIC Educational Resources Information Center

    Hodder, A. Peter

    1990-01-01

    The design and data management of an activity to study weathering by increasing the rate of mineral dissolution in a microwave oven is described. Data analysis in terms of parabolic and first-order kinetics is discussed. (CW)

  4. The science of space weather.

    PubMed

    Eastwood, Jonathan P

    2008-12-13

    The basic physics underpinning space weather is reviewed, beginning with a brief overview of the main causes of variability in the near-Earth space environment. Although many plasma phenomena contribute to space weather, one of the most important is magnetic reconnection, and recent cutting edge research in this field is reviewed. We then place this research in context by discussing a number of specific types of space weather in more detail. As society inexorably increases its dependence on space, the necessity of predicting and mitigating space weather will become ever more acute. This requires a deep understanding of the complexities inherent in the plasmas that fill space and has prompted the development of a new generation of scientific space missions at the international level.

  5. URBAN WET-WEATHER FLOWS

    EPA Science Inventory

    Provides the annual Urban Wet Weather Flow Literture Review for the calendar year 1998 conducted for the Water Environment Federation. It contains hundreds of citations covering the topics of characterization and effects, management, modeling, regulator policies and contol and t...

  6. The International Space Weather Initiative

    NASA Technical Reports Server (NTRS)

    Nat, Gopalswamy; Joseph, Davila; Barbara, Thompson

    2010-01-01

    The International Space Weather Initiative (ISWI) is a program of international cooperation aimed at understanding the external drivers of space weather. The ISWI program has its roots in the successful International Heliophysical Year (IHY) program that ran during 2007 - 2009 and will continue with those aspects that directly affect life on Earth. The primary objective of the ISWI program is to advance the space weather science by a combination of instrument deployment, analysis and interpretation of space weather data from the deployed instruments in conjunction with space data, and communicate the results to the public and students. Like the IHY, the ISWI will be a grass roots organization with key participation from national coordinators in cooperation with an international steering committee. This presentation outlines the ISWI program including its organizational aspects and proposed activities. The ISWI observatory deployment and outreach activities are highly complementary to the CAWSES II activities of SCOSTEP.

  7. Space Weathering Processes on Mercury

    NASA Technical Reports Server (NTRS)

    Noble, S. K.; Pieters, C. M.

    2002-01-01

    Like the Moon, Mercury has no atmosphere to protect it from the harsh space environment and therefore it is expected that it will incur the effects of space weathering. These weathering processes are capable of both creating regolith and altering its optical properties. However, there are many important differences between the environments of Mercury and the Moon. These environmental differences will almost certainly affect the weathering processes as well as the products of those processes. It should be possible to observe the effects of these differences in Vis/NIR spectra of the type expected to be returned by MESSENGER. More importantly, understanding these weathering processes and their consequences is essential for evaluating the spectral data returned from MESSENGER and other missions in order to determine the mineralogy and the iron content of the Mercurian surface. Theoretical and experimental work has been undertaken in order to better understand these consequences.

  8. Basalt-Limestone and Andesite-Limestone Interaction in the Arc Crust - Implications for Volcanic Degassing of CO2

    NASA Astrophysics Data System (ADS)

    Carter, L. B.; Dasgupta, R.

    2014-12-01

    Volcanically emitted CO2 is generally mantle-derived, but high degassing rates at some arcs (e.g. Merapi [1] and Colli Albani Volcanic District [2]) are thought to be affected by magma-carbonate interaction in the upper plate. However, the effects of depth, temperature, and composition on this process are poorly known. We experimentally simulated magma (50%)-limestone (50%) wallrock interactions at 0.5-1.0 GPa, 1100-1200 °C using pure calcite and a hydrous (~3-5 wt.% H2O) melt (basalt, andesite, or dacite). At 1.0 GPa, 1200 °C starting melts are superliquidus, whereas in the presence of calcite, Ca-rich cpx ± Ca-scapolite are produced. With increasing T, basalt-calcite interaction causes the melt, on a volatile-free basis, to become silica-poor and Ca-rich with alumina decreasing as cpx becomes more CaTs-rich. The same trend is seen with all starting melt compositions as P decreases at a constant T (1200 °C), producing melts similar to ultracalcic (CaO/Al2O3>>1) melt inclusions found in arc settings. Shifting from basalt to andesite has little effect on SiO2 and CaO of the reacted melt (e.g. 37 wt.% SiO2, 42 wt.% CaO at 0.5 GPa, 1200 °C), whereas Al2O3 of andesite-derived reacted melt is lower, likely a result of lower alumina in the starting andesite. Wall-rock calcite consumption is observed to increase with increasing T, decreasing P, and increasing melt XSiO2. At 0.5 GPa between 1100 and 1200 °C, our basalt experiments yield carbonate assimilation from 22 to 48 wt.%. This decreases to 20 wt.% at 1.0 GPa, 1200 °C, whereas an andesitic composition assimilates 59 to 52 wt.% from 0.5 to 1.0 GPa at 1200 °C. The higher assimilation in andesite-added runs at high-T is because of lower silicate liquidus as evidenced by lower modal proportion or absence of cpx ± scapolite. Using a magma flux rate estimated for Mt. Vesuvius [3], we obtain a CO2 outflux for a single such volcano experiencing arc magma-calcite reaction [4] of at least 2-4% of the present

  9. Efficacy of chemical treatment of the Pietra cantone limestone in the restoration of historic buildings of Cagliari (southern Sardinia, Italy)

    NASA Astrophysics Data System (ADS)

    Columbu, Stefano; Lisci, Carla; Sitzia, Fabio; Buccellato, Giampaolo

    2015-04-01

    The present work aims to evaluate the efficacy of some chemical products in the restoration works of the "Pietra cantone" limestone, a calcarenitic rock belonging to the carbonatic miocenic series (lower Tortonian) of Cagliari (southern Sardinia, Italy), widely used in historic buildings. Such stone, once used in the masonry, if is not protected by plaster or in the presence of aqueous solutions circulating, frequently shows problems of chemical-physical decay, due to their petrophysical characteristics. In fact, being characterized by a highly porous (on average 35-42% vol.) carbonate matrix low-medium cemented, are easily alterable by weathering processes (i.e., dissolution, sulfation, etc.) and by cyclic mechanism of crystallization/solubilisation of salts and hydration/dehydration of hygroscopic phases belonging to the clay component of these calcarenites. These processes induce negative effects on physical-mechanical properties of stone, producing various macroscopic forms of alteration such as decohesion, disintegration, exfoliation, alveolation, etc. Where the decay of the walls is in an advanced stage, there was a strong retreat of the vertical profile of the facade of the building, resulting in critical static-structural. As a case study was taken the historic building of a tobacco manufacture, one of the first industrial establishments in Cagliari, then owned by the Italian State Monopoly. The factory dates back to the early decades of the XVIII century, the walls of which, however, belonged to the convent of the "Frati Minori" built towards the end of the XIV century along the wall that closed the east the historic district of "Marina" in front of the port of Cagliari. In addressing the structural restoration of this building, before selecting chemical products for dealing adequately of limestone, we proceeded at the outset to a thorough analysis of the structures built in "Pietra Cantone", and their physical-mechanical decay. Only thereafter the stone

  10. Rapid method to determine actinides and 89/90Sr in limestone and marble samples

    DOE PAGES

    Maxwell, Sherrod L.; Culligan, Brian; Hutchison, Jay B.; ...

    2016-04-12

    A new method for the determination of actinides and radiostrontium in limestone and marble samples has been developed that utilizes a rapid sodium hydroxide fusion to digest the sample. Following rapid pre-concentration steps to remove sample matrix interferences, the actinides and 89/90Sr are separated using extraction chromatographic resins and measured radiometrically. The advantages of sodium hydroxide fusion versus other fusion techniques will be discussed. Lastly, this approach has a sample preparation time for limestone and marble samples of <4 hours.

  11. Passive treatment of acid mine drainage in down-flow limestone systems

    SciTech Connect

    Watzlaf, G.R.

    1997-12-31

    Passive down-flow systems, consisting of compost and/or limestone layers, may be well suited for treatment of acidic mine drainage containing ferric iron and/or aluminum. Two columns were constructed and operated in the laboratory. The first column simulated a downward, vertical-flow anaerobic wetland, also referred to as successive alkalinity-producing systems (SAPS), and has received mine drainage for 97 weeks. The 0.16-m diameter column was vertically oriented and (from bottom to top) consisted of a 0.30-m thick layer of limestone, a 0.76-m thick layer of spent mushroom compost, and 0.91 m of free standing water. Water flowed vertically downward through the system. A second column, filled with only limestone, received water from the same source as the first column. This limestone column contained a 1.06-m thick layer of limestone and 0.91 m of free standing water and has received water for 55 weeks. Actual acid mine drainage (pH = 3.1, acidity = 200 mg/L (as CaCO{sub 3}), SO{sub 4}{sup 2-} = 600 mg/L, Total Fe = 10 mg/L, Mn = 14 mg/L, and Al = 18 mg/L) was collected every two weeks from a nearby abandoned deep mine and applied to these columns at a rate of 3.8 mL/min. For the compost/limestone column, effluent pH remained above 6.2 (6.2-7.9); however, pH at a depth of 0.38 m in the compost (halfway) dropped to < 4 after 28 weeks (net acidic). At the bottom of the compost pH remained > 4.5 for all 97 weeks. Alkalinity was generated by a combination of limestone dissolution and sulfate reduction. Over the 97 week period, the column generated an average of 330 mg/L of alkalinity, mostly due to limestone dissolution. Bacterial sulfate reduction displayed an ever decreasing trend, initially accounting for more than 200 mg/L of alkalinity and after 40 weeks only accounting for about 50 mg/L.

  12. Discrimination of moist oil shale and limestone using laser induced breakdown spectroscopy

    NASA Astrophysics Data System (ADS)

    Paris, P.; Piip, K.; Lepp, A.; Lissovski, A.; Aints, M.; Laan, M.

    2015-05-01

    Laser-induced plasma emission spectra of Estonian oil shale and associated limestone with varying moisture content were studied. Time gated spectra excited by 1064 nm laser radiation were recorded. Spectral lines for determination of plasma parameters were selected. Moisture causes the reduction of the intensity of the total emission, and increases the intensity of the Hα line. It was found that the effect of the moisture content on the plasma temperature and electron concentration was inconsiderable. Using the ratio of intensities of Hα and Mg spectral lines, it was possible to distinguish reliably between limestone and oil shale independently of their moisture content.

  13. Space Weathering of Small Bodies

    NASA Astrophysics Data System (ADS)

    McFadden, L. A.

    2002-12-01

    Space weathering is defined as any process that wears away and alters surfaces, here confined to small bodies in the Solar System. Mechanisms which possibly alter asteroid and comet surfaces include solar wind bombardment, UV radiation, cosmic ray bombardment, micrometeorite bombardment. These processes are likely to contribute to surface processes differently. For example, solar wind bombardment would be more important on a body closer to the Sun compared to a comet where cosmic ray bombardment might be a more significant weathering mechanism. How can we measure the effects of space weathering? A big problem is that we don't know the nature of the surface before it was weathered. We are in a new era in the study of surface processes on small bodies brought about by the availability of spatially resolved, color and spectral measurements of asteroids from Galileo and NEAR. What processes are active on which bodies? What physics controls surface processes in different regions of the solar system? How do processes differ on different bodies of different physical and chemical properties? What combinations of observable parameters best address the nature of surface processes? Are there alternative explanations for the observed parameters that have been attributed to space weathering? Should we retain the term, space weathering? How can our understanding of space weathering on the Moon help us understand it on asteroids and comets? Finally, we have to leave behind some presuppositions, one being that there is evidence of space weathering based on the fact that the optical properties of S-type asteroids differs from those of ordinary chondrites.

  14. Temperature dependence of basalt weathering

    NASA Astrophysics Data System (ADS)

    Li, Gaojun; Hartmann, Jens; Derry, Louis A.; West, A. Joshua; You, Chen-Feng; Long, Xiaoyong; Zhan, Tao; Li, Laifeng; Li, Gen; Qiu, Wenhong; Li, Tao; Liu, Lianwen; Chen, Yang; Ji, Junfeng; Zhao, Liang; Chen, Jun

    2016-06-01

    The homeostatic balance of Earth's long-term carbon cycle and the equable state of Earth's climate are maintained by negative feedbacks between the levels of atmospheric CO2 and the chemical weathering rate of silicate rocks. Though clearly demonstrated by well-controlled laboratory dissolution experiments, the temperature dependence of silicate weathering rates, hypothesized to play a central role in these weathering feedbacks, has been difficult to quantify clearly in natural settings at landscape scale. By compiling data from basaltic catchments worldwide and considering only inactive volcanic fields (IVFs), here we show that the rate of CO2 consumption associated with the weathering of basaltic rocks is strongly correlated with mean annual temperature (MAT) as predicted by chemical kinetics. Relations between temperature and CO2 consumption rate for active volcanic fields (AVFs) are complicated by other factors such as eruption age, hydrothermal activity, and hydrological complexities. On the basis of this updated data compilation we are not able to distinguish whether or not there is a significant runoff control on basalt weathering rates. Nonetheless, the simple temperature control as observed in this global dataset implies that basalt weathering could be an effective mechanism for Earth to modulate long-term carbon cycle perturbations.

  15. Weather data dissemination to aircraft

    NASA Technical Reports Server (NTRS)

    Mcfarland, Richard H.; Parker, Craig B.

    1990-01-01

    Documentation exists that shows weather to be responsible for approximately 40 percent of all general aviation accidents with fatalities. Weather data products available on the ground are becoming more sophisticated and greater in number. Although many of these data are critical to aircraft safety, they currently must be transmitted verbally to the aircraft. This process is labor intensive and provides a low rate of information transfer. Consequently, the pilot is often forced to make life-critical decisions based on incomplete and outdated information. Automated transmission of weather data from the ground to the aircraft can provide the aircrew with accurate data in near-real time. The current National Airspace System Plan calls for such an uplink capability to be provided by the Mode S Beacon System data link. Although this system has a very advanced data link capability, it will not be capable of providing adequate weather data to all airspace users in its planned configuration. This paper delineates some of the important weather data uplink system requirements, and describes a system which is capable of meeting these requirements. The proposed system utilizes a run-length coding technique for image data compression and a hybrid phase and amplitude modulation technique for the transmission of both voice and weather data on existing aeronautical Very High Frequency (VHF) voice communication channels.

  16. Does the Weather Really Matter?

    NASA Astrophysics Data System (ADS)

    Burroughs, William James

    1997-09-01

    We talk about it endlessly, write about it copiously, and predict it badly. It influences what we do, what we wear, and how we live. Weather--how does it really impact our lives? In this compelling look at weather, author Burroughs combines historical perspective and economic and political analysis to give the impact of weather and climate change relevance and weight. He examines whether the frequency of extreme events is changing and the consequences of these changes. He looks at the chaotic nature of the climate and how this unpredictability can impose serious limits on how we plan for the future. Finally, he poses the important question: what types of serious, even less predictable changes are around the corner? In balanced and accessible prose, Burroughs works these issues into lucid analysis. This refreshing and insightful look at the impact of weather will appeal to anyone who has ever worried about forgetting an umbrella. William James Burroughs is the author of Watching the World's Weather (CUP, 1991) and Weather Cycles: Real or Imaginary? (CUP, 1994).

  17. Modeling the influence of organic acids on soil weathering

    USGS Publications Warehouse

    Lawrence, Corey R.; Harden, Jennifer W.; Maher, Kate

    2014-01-01

    Biological inputs and organic matter cycling have long been regarded as important factors in the physical and chemical development of soils. In particular, the extent to which low molecular weight organic acids, such as oxalate, influence geochemical reactions has been widely studied. Although the effects of organic acids are diverse, there is strong evidence that organic acids accelerate the dissolution of some minerals. However, the influence of organic acids at the field-scale and over the timescales of soil development has not been evaluated in detail. In this study, a reactive-transport model of soil chemical weathering and pedogenic development was used to quantify the extent to which organic acid cycling controls mineral dissolution rates and long-term patterns of chemical weathering. Specifically, oxalic acid was added to simulations of soil development to investigate a well-studied chronosequence of soils near Santa Cruz, CA. The model formulation includes organic acid input, transport, decomposition, organic-metal aqueous complexation and mineral surface complexation in various combinations. Results suggest that although organic acid reactions accelerate mineral dissolution rates near the soil surface, the net response is an overall decrease in chemical weathering. Model results demonstrate the importance of organic acid input concentrations, fluid flow, decomposition and secondary mineral precipitation rates on the evolution of mineral weathering fronts. In particular, model soil profile evolution is sensitive to kaolinite precipitation and oxalate decomposition rates. The soil profile-scale modeling presented here provides insights into the influence of organic carbon cycling on soil weathering and pedogenesis and supports the need for further field-scale measurements of the flux and speciation of reactive organic compounds.

  18. Titan: Callisto With Weather?

    NASA Astrophysics Data System (ADS)

    Moore, J. M.; Pappalardo, R. T.

    2008-12-01

    , Titan might have accreted relatively cold. Without being in a forced resonance, Titan's interior may have never undergone significant tidal heating. Analogous to Callisto's tenuous CO2 atmosphere, believed to be generated by sublimation of interior ices, interior clathrated methane within Titan may slowly diffuse outward from the cold interior, rather than the atmosphere being replenished by cryovolcanism. The hypothesis that Titan is "Callisto with weather" -- with geological processes that are principally exogenic -- can be tested through geophysical and thermal modeling, and by modeling the evolution of landscapes that are shaped by exogenic processes alone.

  19. 46 CFR 45.187 - Weather limitations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Weather limitations. 45.187 Section 45.187 Shipping... River Barges on Lake Michigan Routes § 45.187 Weather limitations. (a) Tows on the Burns Harbor route must operate during fair weather conditions only. (b) The weather limits (ice conditions, wave...

  20. 46 CFR 45.187 - Weather limitations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Weather limitations. 45.187 Section 45.187 Shipping... River Barges on Lake Michigan Routes § 45.187 Weather limitations. (a) Tows on the Burns Harbor route must operate during fair weather conditions only. (b) The weather limits (ice conditions, wave...

  1. 46 CFR 45.187 - Weather limitations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Weather limitations. 45.187 Section 45.187 Shipping... River Barges on Lake Michigan Routes § 45.187 Weather limitations. (a) Tows on the Burns Harbor route must operate during fair weather conditions only. (b) The weather limits (ice conditions, wave...

  2. 46 CFR 45.187 - Weather limitations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Weather limitations. 45.187 Section 45.187 Shipping... River Barges on Lake Michigan Routes § 45.187 Weather limitations. (a) Tows on the Burns Harbor route must operate during fair weather conditions only. (b) The weather limits (ice conditions, wave...

  3. 46 CFR 45.187 - Weather limitations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Weather limitations. 45.187 Section 45.187 Shipping... River Barges on Lake Michigan Routes § 45.187 Weather limitations. (a) Tows on the Burns Harbor route must operate during fair weather conditions only. (b) The weather limits (ice conditions, wave...

  4. Integration of Weather Avoidance and Traffic Separation

    NASA Technical Reports Server (NTRS)

    Consiglio, Maria C.; Chamberlain, James P.; Wilson, Sara R.

    2011-01-01

    This paper describes a dynamic convective weather avoidance concept that compensates for weather motion uncertainties; the integration of this weather avoidance concept into a prototype 4-D trajectory-based Airborne Separation Assurance System (ASAS) application; and test results from a batch (non-piloted) simulation of the integrated application with high traffic densities and a dynamic convective weather model. The weather model can simulate a number of pseudo-random hazardous weather patterns, such as slow- or fast-moving cells and opening or closing weather gaps, and also allows for modeling of onboard weather radar limitations in range and azimuth. The weather avoidance concept employs nested "core" and "avoid" polygons around convective weather cells, and the simulations assess the effectiveness of various avoid polygon sizes in the presence of different weather patterns, using traffic scenarios representing approximately two times the current traffic density in en-route airspace. Results from the simulation experiment show that the weather avoidance concept is effective over a wide range of weather patterns and cell speeds. Avoid polygons that are only 2-3 miles larger than their core polygons are sufficient to account for weather uncertainties in almost all cases, and traffic separation performance does not appear to degrade with the addition of weather polygon avoidance. Additional "lessons learned" from the batch simulation study are discussed in the paper, along with insights for improving the weather avoidance concept. Introduction

  5. Rare Earth Elements reveal past earthquakes on limestone normal faults

    NASA Astrophysics Data System (ADS)

    Manighetti, I.; Boucher, E.; Chauvel, C.; Schlagenhauf, A.; Benedetti, L.

    2009-12-01

    In 2008, we suggested that the chemical composition of the rocks which form well preserved, seismically exhumed fault scarps might record past major earthquakes (Carcaillet et al., 2008) because those scarp surfaces consist of a vertical succession of zones that have been exposed at different times by the repeating earthquakes, thus weathered over different time spans. In this pioneer study, we validated this hypothesis using the changes in chemical compositions (major and trace elements) of 15 carbonate rock samples collected from the base to the top of the seismically exhumed, 10 m-high Magnola normal fault scarp (Abruzzes, Central Italy). However, the number of available samples was insufficient to fully assess the validity of the model. Here we present trace element data on 27 additional samples collected systematically every 25 cm along the Magnola scarp, as well as on 7 scarp samples buried below the colluvium hence representing the first 4 meters of the scarp before exhumation. The scarp rocks buried in the first meter of the ground appear significantly enriched in Rare Earth elements (REE): they contain 60% more REE than the rocks located either deeper in the ground or immediately above the ground level. This concentration peak most probably results from enrichment of the scarp rocks by interaction with the impurity-doped, acidic, upper soil. Above the ground surface and along the scarp, most element concentrations (70%) decrease up-dip, generally by more than 50%; we attribute this trend to leaching and dissolution-recrystallization of purer calcite through time. The top of the scarp having been exposed for a longer period of time, its surface lost more of the trace elements contained in the rocks. However, the upward decrease in REE contents is not linear and 4 REE concentration peaks can be recognized along the exposed scarp. The position of these 4 peaks coincide with the zones identified by Schlagenhauf et al. (2009) and Palumbo et al. (2004) as

  6. 3D Stress-Strain Analysis of a Failed Limestone Wedge Influenced by an Intact Rock Bridge

    NASA Astrophysics Data System (ADS)

    Paronuzzi, Paolo; Bolla, Alberto; Rigo, Elia

    2016-08-01

    This paper presents a back-analysis of a rock wedge failure (volume = 25-30 m3) that involved a limestone scarp in the Rosandra valley (Trieste karst, NE Italy). Thanks to the mechanical survey of the detachment surface, a single rock bridge having a size of about 15 cm × 30 cm has been ascertained. A 3D stress-strain analysis has been performed to examine the influence of the rock bridge on the block stability (initial unweathered condition: strength reduction factor SRF equal to 1.14). The shear strength provided by the basal and lateral joints represents the main contributing factor for the wedge stability (about 60-75 % of the whole resisting system). However, the equilibrium of the wedge was temporarily attained thanks to the strength contribution provided by the rock bridge (25-40 %) until the acting forces locally exceeded the resisting forces, thus determining the bridge rupture and, as a consequence, the wedge collapse. The mean shear stress acting on the rock bridge at failure ranges from about 3.5 to 5 MPa. Calculated block displacements up to failure vary from 0.6 to 1.5 mm, depending on the different elastic modulus assumed for the wedge ( E = 30, 10, and 4 GPa). Pre-collapse block displacements increase as a result of the shear strength decrease that was initially caused by the weathering of the delimiting rock joints and, further, by the progressive failure of the rock bridge. The cohesion at failure of the rock bridge ranges from 2.1 to 2.6 MPa (friction angle of intact rock φ = 40°).

  7. Use of limestone obtained from waste of the mussel cannery industry for the production of mortars

    SciTech Connect

    Ballester, Paloma; Marmol, Isabel; Morales, Julian; Sanchez, Luis . E-mail: luis-sanchez@uco.es

    2007-04-15

    Various types of cement-SiO{sub 2}-CaCO{sub 3} mortar were prepared by replacing quarry limestone aggregate with limestone obtained as a by-product from waste of the mussel cannery industry. The CaCO{sub 3} aggregate consists mainly of elongated prismatic particles less than 4 {mu}m long rather than of the rounded particles of smaller size (2-6 {mu}m) obtained with quarry limestone. The mechanical and structural properties of the mortars were found to be influenced by aggregate morphology. Setting of the different types of mortar after variable curing times was evaluated by scanning electron microscopy (SEM), thermogravimetric analysis (TG) and mercury intrusion porosimetry (MIP) techniques. Mortars with a high content in mussel shell limestone exhibited a more packed microstructure, which facilitates setting of cement and results in improved mortar strength. The enhanced mechanical properties of the new mortars allow the cement content in the final mortar composition to be decreased and production costs to be reduced as a result.

  8. Effects of limestone petrography and calcite microstructure on OPC clinker raw meals burnability

    NASA Astrophysics Data System (ADS)

    Galimberti, Matteo; Marinoni, Nicoletta; Della Porta, Giovanna; Marchi, Maurizio; Dapiaggi, Monica

    2016-12-01

    Limestone represents the main raw material for ordinary Portland cement clinker production. In this study eight natural limestones from different geological environments were chosen to prepare raw meals for clinker manufacturing, aiming to define a parameter controlling the burnability. First, limestones were characterized by X-Ray Fluorescence, X-Ray Powder Diffraction and Optical Microscopy to assess their suitability for clinker production and their petrographic features. The average domains size and the microstrain of calcite were also determined by X-Ray Powder Diffraction line profile analysis. Then, each limestone was admixed with clay minerals to achieve the adequate chemical composition for clinker production. Raw meals were thermally threated at seven different temperatures, from 1000 to 1450 °C, to evaluate their behaviour on heating by ex situ X-Ray Powder Diffraction and to observe the final clinker morphology by Scanning Electron Microscopy. Results indicate the calcite microstrain is a reliable parameter to predict the burnability of the raw meals, in terms of calcium silicates growth and lime consumption. In particular, mixtures prepared starting from high-strained calcite exhibit a better burnability. Later, when the melt appears this correlation vanishes; however differences in the early burnability still reflect on the final clinker composition and texture.

  9. Treatment Of Metal-Mine Effluents By Limestone Neutralization And Calcite Co-Precipitation (Presentation)

    EPA Science Inventory

    The U.S. Geological Survey - Leetown Science Center and the Colorado School of Mines have developed a remediation process for the treatment of metals in circumneutral mining influenced waters. The process involves treatment with a pulsed limestone bed (PLB) system, followed by c...

  10. Treatment Of Metal-Mine Effluents By Limestone Neutralization And Calcite Co-Precipitation

    EPA Science Inventory

    The U.S. Geological Survey - Leetown Science Center and the Colorado School of Mines have developed a remediation process for the treatment of metals in circumneutral mining influenced waters. The process involves treatment with a pulsed limestone bed (PLB) system, followed by c...

  11. Hydrology of the cavernous limestones of the Mammoth Cave area, Kentucky

    USGS Publications Warehouse

    Brown, Richmond F.

    1966-01-01

    The Mammoth Cave National Park in central Kentucky offers a unique opportunity to study the occurrence of ground water in limestone under natural conditions. Ground water occurs as perched and semiperched bodies in alternate sandstone, shale, and limestone formations and under water-table conditions at the approximate level of the Green River in thick soluble limestone. Three continuous recorders that operated for 5 years indicate that precipitation on the Mammoth Cave plateau recharges the underlying sandstone rapidly. Ground water from the sandstone discharges horizontally to the edges of the plateau and vertically to underlying formations. Some of the precipitation recharges underlying formations almost immediately through overland flow to sinkholes and free fall through open shafts to pools at the water table. Much of the precipitation on the Pennyroyal plain flows overland into sinkholes and then through solution openings to the Green River. Water from the Green River flows into limestone solution channels under Mammoth Cave plateau at some stages, and this water discharges again to the Green River downstream. The presence of salt water, high in chloride in the Green River, makes it possible to trace the movement of the river water through the underground streams. Graphs show relationships of chloride concentration, stage of the Green River, time, precipitation, ground-water levels, and stratigraphy.

  12. Limestone characterization to model damage from acidic precipitation: Effect of pore structure on mass transfer

    USGS Publications Warehouse

    Leith, S.D.; Reddy, M.M.; Irez, W.F.; Heymans, M.J.

    1996-01-01

    The pore structure of Salem limestone is investigated, and conclusions regarding the effect of the pore geometry on modeling moisture and contaminant transport are discussed based on thin section petrography, scanning electron microscopy, mercury intrusion porosimetry, and nitrogen adsorption analyses. These investigations are compared to and shown to compliment permeability and capillary pressure measurements for this common building stone. Salem limestone exhibits a bimodal pore size distribution in which the larger pores provide routes for convective mass transfer of contaminants into the material and the smaller pores lead to high surface area adsorption and reaction sites. Relative permeability and capillary pressure measurements of the air/water system indicate that Salem limestone exhibits high capillarity end low effective permeability to water. Based on stone characterization, aqueous diffusion and convection are believed to be the primary transport mechanisms for pollutants in this stone. The extent of contaminant accumulation in the stone depends on the mechanism of partitioning between the aqueous and solid phases. The described characterization techniques and modeling approach can be applied to many systems of interest such as acidic damage to limestone, mass transfer of contaminants in concrete and other porous building materials, and modeling pollutant transport in subsurface moisture zones.

  13. Optimization of nanolime solvent for the consolidation of coarse porous limestone

    NASA Astrophysics Data System (ADS)

    Borsoi, Giovanni; Lubelli, Barbara; van Hees, Rob; Veiga, Rosário; Silva, António Santos

    2016-09-01

    The potentialities of nanomaterials for application in the field of conservation have been widely investigated in the last two decades. Among nanomaterials, nanolimes, i.e., dispersions of lime nanoparticles in alcohols are promising consolidating products for calcareous materials. Nanolimes are effective in recovering the very superficial loss of cohesion of decayed materials, but they do not always provide sufficient mass consolidation. This limitation is mainly related to the deposition of the nanoparticles nearby the surface of the material. Experimental research has been set up with the aim of improving the in-depth deposition of lime nanoparticles. Previous research by the authors has shown that nanolime deposition within a substrate can be controlled by adapting the nanolimes properties (kinetic stability and evaporation rate) to the moisture transport behavior of the substrate. Nanolime properties can be modified by the use of different solvents. In this research, nanolime dispersions have been further optimized for application on Maastricht limestone, a coarse porous limestone. Firstly, nanolimes were synthesized and dispersed in ethanol and/or water, both pure and mixed in different percentages. Subsequently, based on the kinetic stability of the nanolime dispersions, the most promising solvent mixtures were selected and applied on the limestone. The deposition of lime nanoparticles within the limestone was studied by phenolphthalein test, optical microscopy and scanning electron microscopy. The results confirm that nanolime dispersed in a mixture of ethanol (95 %) and water (5 %) can guarantee a better nanoparticles in-depth deposition within coarse porous substrates, when compared to dispersions in pure ethanol.

  14. Environmentally acceptable effect of hydrogen peroxide on cave "lamp-flora", calcite speleothems and limestones.

    PubMed

    Faimon, Jirí; Stelcl, Jindrich; Kubesová, Svatava; Zimák, Jirí

    2003-01-01

    Mosses, algae, and cyanobacteria (lamp-flora) colonize illuminated areas in show caves. This biota is commonly removed by a sodium hypochlorite solution. Because chlorine and other deleterious compounds are released into a cave environment during lamp-flora cleansing, hydrogen peroxide was tested as an alternative agent. In a multidisciplinary study conducted in the Kateinská Cave (Moravian Karst, Czech Republic), 12 algae- and cyanobacteria taxons and 19 moss taxons were detected. The threshold hydrogen peroxide concentration for the destruction of this lamp-flora was found to be 15 vol.%. Based on laboratory experiments in stirred batch reactors, the dissolution rates of limestones and calcite speleothems in water were determined as 3.77 x 10-3 and 1.81 x 10-3 mol m-2 h-1, respectively. In the 15% peroxide solution, the limestone and speleothem dissolution rates were one order of magnitude higher, 2.00 x 10-2 and 2.21 x 10-2 mol m-2 h-1, respectively. So, the peroxide solution was recognised to attack carbonates somewhat more aggressively than karst water. In order to prevent the potential corrosion of limestone and speleothems, the reaching of preliminary peroxide saturation with respect to calcite is recommended, for example, by adding of few limestone fragments into the solution at least 10 h prior to its application.

  15. Oxygen and carbon isotopic composition of limestones and dolomites, bikini and eniwetok atolls.

    PubMed

    Gross, M G; Tracey, J I

    1966-03-04

    Aragonitic, unconsolidated sediments from the borings on the Eniwetok and Bikini atolls are isotopically identical with unaltered skeletal fragments, whereas the recrystallized limestones exhibit isotopic variations resulting from alteration in meteoric waters during periods of emergence. Dolomites and associated calcites are enriched in O(18), perhaps because of interaction with hypersaline brines.

  16. Use of glass fiber-reinforced plastic as an absorber in limestone wet flue gas desulfurization.

    PubMed

    Lin, Haibo

    2008-10-01

    The choice of materials for the spraying and oxidation of pipes directly affect the operation in limestone wet flue gas desulfurization (FGD). There is reason to consider using glass fiber-reinforced plastic (FRP) instead of expensive high nickel alloy for the spraying and oxidation of pipes.

  17. Demonstration of a hydration process for reactivating partially sulfated limestone sorbents

    SciTech Connect

    Smith, G.W.; Hajicek, D.R.; Myles, K.M.; Goblirsch, G.M.; Mowry, R.W.; Teats, F.G.

    1981-10-01

    The utilization of limestione sorbent for the removal of SO/sub 2/ in coal combustion in an atmospheric fluidized-bed combustor (AFBC) can be markedly increased by reactivating the partially sulfated limestone for reuse in the combustor. Such reuse would reduce costs and the environmental impact of quarrying and disposing of large quantities of limestone. The reactivation process consists of hydrating the partially sulfated limestone by treatment with water. A demonstration of the hydration process and the reuse of the reactivated limestone were carried out at Grand Forks Energy Technology Center (GFETC) in cooperation with Argonne National Laboratory (ANL). The data obtained in the GFETC 0.2-m/sup 2/ AFBC are compared with those obtained earlier in the ANL 0.02-m/sup 2/ AFBC. Marked enhancement of calcium utilization was achieved in both studies, but differences were noted in the degree of enhancement and in the Ca/S mole ratios required to maintain SO/sub 2/ in the off-gas at an acceptable level.

  18. The mechanics of intersecting echelon veins and pressure solution seams in limestone

    NASA Astrophysics Data System (ADS)

    Seyum, Solomon; Pollard, David D.

    2016-08-01

    Many studies that describe the formation of echelon vein arrays relate the causative stresses implicitly to the deformation, reliant on simple shear kinematics, such that the vein-to-array angle and the array width are the primary physical quantities. In contrast, we identify twelve physical quantities to describe echelon veins in two dimensions, including coeval, vein-intersecting, pressure solution seams. A finite element method is used to reproduce vein shapes in linear elastic and elastic-perfectly plastic model limestone. Model vein geometries are designed using values within the range of geometries measured from echelon veins at Raplee Anticline and Comb Monocline, Utah. Four physical quantities are significant for describing echelon vein shapes: vein spacing, vein-array angle, limestone elastic stiffness, and closing of orthogonal pressure solution seams. Pressure solution seam closing influences the mechanical interaction between adjacent veins, and for a range of conditions, causes a nearly linear vein opening distribution (triangular shapes) and encourages straight vein propagation, both of which approximate field measurements. Model results show that small spacing of veins with seams and large vein-array angles promote straight vein traces in limestone with stiffness typical of laboratory measurements, given the physical geologic conditions inferred from the burial history of the limestone strata.

  19. Adsorption/desorption of phosphorus on limestone from the Biscayne Aquifer under freshwater and seawater conditions.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Areas of seawater intrusion are known geochemically active regions particularly in limestone aquifers, where carbonate mineral dissolution and ion exchange reactions are important. Both of these processes can lead to a release of phosphorus from the aquifer matrix to the groundwater as seawater int...

  20. Facies development and paleoenvironment of the Hajajah Limestone Member, Aruma Formation, central Saudi Arabia

    NASA Astrophysics Data System (ADS)

    El-Sorogy, Abdelbaset S.; Ismail, Abdelmoneim; Youssef, Mohamed; Nour, Hamdy

    2016-12-01

    The Campanian Hajajah Limestone Member of the Aruma Formation was formed during two regressive episodes. Each of them formed of three depositional facies, from base to top: 1) intra-shelf basin facies, made up of fossiliferous green shale and mudstone with ostracods and badly preserved foraminifers. 2) fore-reef facies, consists of hard, massive, marly coralline limestone. The upper part is rich with low divers, badly to moderate preserved, solitary and colonial corals, and, 3) back reef and near-shore facies, consists of fossiliferous sandy dolomitized, bioturbated limestone with abundant reworked corals, bivalves, gastropods, and aggregate grains. On the basis of field observations, micro-and macrofossils and microfacies analysis, the Hajajah Limestone Member was deposited in distal marine settings below storm wave base in a low-energy environment changed upward to fore-reef framework in an open marine environment with moderate to high energy conditions and terminated with shallow marine facies with accumulation of skeletal grains by storms during regression.