WorldWideScience

Sample records for french porous limestone

  1. Effect of SO2 Dry Deposition on Porous Dolomitic Limestones

    Directory of Open Access Journals (Sweden)

    Florica Doroftei

    2010-01-01

    Full Text Available The present study is concerned with the assessment of the relative resistance of a monumental dolomitic limestone (Laspra – Spain used as building material in stone monuments and submitted to artificial ageing by SO2 dry deposition in the presence of humidity. To investigate the protection efficiency of different polymeric coatings, three commercially available siloxane-based oligomers (Lotexan-N, Silres BS 290 and Tegosivin HL 100 and a newly synthesized hybrid nanocomposite with silsesquioxane units (TMSPMA were used. A comparative assessment of the data obtained in this study underlines that a better limestone protection was obtained when treated with the hybrid nanocomposite with silsesquioxane units.

  2. Optimization of nanolime solvent for the consolidation of coarse porous limestone

    Science.gov (United States)

    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.

  3. Compositional characterization of French limestone: a new tool for art historians

    International Nuclear Information System (INIS)

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

    1994-01-01

    Limestone from quarries known to medieval craftsmen and from the monuments they built and embellished, as well as from carvings now in museum collections, has been characterized by neutron activation analysis. Specimens form 38 quarries in the Lutetian and Jurassic limestone formations of France and from sculptures in American and French museums have been tested, and the results have been compiled in a data base to which art historians may refer when attempting to determine provenance for sculptures. Multivariate statistical analysis of concentration data shows stone form a particular quarry in the Paris basin to be compositionally homogeneous and distinguishable from other quarries in the same formation. The same approach to data related to quarries near the Burgundian abbey of Cluny finds general agreement between classifications based on compositional and on petrographic data. (Author)

  4. Effective stress law for the permeability and deformation of four porous limestones

    Science.gov (United States)

    Wang, Y.; Meng, F.; Wang, X.; Baud, P.; Wong, T. F.

    2017-12-01

    The effective stress behavior of a rock is related to the geometric of its pore space. In a microscopically homogeneous assemblage, effective stress coefficients for permeability, volumetric strain and porosity change are predicted to be equal to or less than unity. Experimental measurements are in basic agreement with this prediction, with exceptions particularly in clay-rich sandstones, for which effective stress coefficient for permeability up to 7 was documented. Little is known about carbonates, but Ghabezloo et al. [2009] studied the permeability of an oolitic limestone (from Nimes, France) with 17% porosity and reported effective stress coefficients up to 2.4. We investigated this phenomenon in Indiana, Leitha, Purbeck, and Thala limestones with porosities of 13-30%. Measurements were made at room temperature on water-saturated samples at confining and pore pressures of 7-15 MPa and 1-3 MPa, respectively. Unlike previous studies limited to the permeability, we also determined the effective stress coefficients for volumetric strain and porosity change. Indiana limestone is oolitic, and not surprisingly its behaviour was similar to Nimes limestone, with an effective stress coefficient for permeability of 2.5. Our Indiana limestone data showed that whereas the effective stress coefficient for volumetric strain was 1. Measurements on Purbeck and Thala limestones are consistent with these inequalities, with effective stress coefficients for permeability and porosity change >1 and that for volumetric strain <1. Even though Purbeck and Thala limestones are micritic with appreciable amount of quartz and dolomite, microstructural and mercury porosimetry data showed that their pore spaces are similar to the oolitic limestones, in that the pore size distribution is bimodal with significant fractions of both macropores and micropores. Berryman [1992] analyzed theoretically a rock made up of two porous constituents. Our new data are in agreement with inequalities he

  5. Soluble salt sources in medieval porous limestone sculptures: A multi-isotope (N, O, S) approach

    Energy Technology Data Exchange (ETDEWEB)

    Kloppmann, W., E-mail: w.kloppmann@brgm.fr [BRGM, Direction des Laboratoires, Unité Isotopes, BP 6009, F-45060 Orléans cedex 2 (France); Rolland, O., E-mail: olivierrolland@wanadoo.fr [Montlouis-sur-Loire (France); Proust, E.; Montech, A.T. [BRGM, Direction des Laboratoires, Unité Isotopes, BP 6009, F-45060 Orléans cedex 2 (France)

    2014-02-01

    The sources and mechanisms of soluble salt uptake by porous limestone and the associated degradation patterns were investigated for the life-sized 15th century “entombment of Christ” sculpture group located in Pont-à-Mousson, France, using a multi-isotope approach on sulphates (δ{sup 34}S and δ{sup 18}O) and nitrates (δ{sup 15}N and δ{sup 18}O). The sculpture group, near the border of the Moselle River, is within the potential reach of capillary rise from the alluvial aquifer. Chemical analyses show a vertical zonation of soluble salts with a predominance of sulphates in the lower parts of the statues where crumbling and blistering prevail, and higher concentrations of nitrates and chloride in the high parts affected by powdering and efflorescence. Isotope fingerprints of sulphates suggest a triple origin: (1) the lower parts are dominated by capillary rise of dissolved sulphate from the Moselle water with characteristic Keuper evaporite signatures that progressively decreases with height; (2) in the higher parts affected by powdering the impact of atmospheric sulphur becomes detectable; and (3) locally, plaster reparations impact the neighbouring limestone through dissolution and re-precipitation of gypsum. Nitrogen and oxygen isotopes suggest an organic origin of nitrates in all samples. N isotope signatures are compatible with those measured in the alluvial aquifer of the Moselle River further downstream. This indicates contamination by sewage or organic fertilisers. Significant isotopic contrasts are observed between the different degradation features depending on the height and suggest historical changes of nitrate sources. - Highlights: • We use S, N and O isotopes to distinguish salt sources in limestone sculptures. • Vertical zonation of degradation is linked to capillary rise and air pollution. • Sulphate salts in lower parts are derived from river/groundwater. • Sulphate salts in higher parts show signature of air pollution. • Nitrates

  6. Moisture distribution in the stone portal of a church: how it influences the salt accumulation in porous limestone

    Science.gov (United States)

    Török, Ákos; Galambos, Éva

    2017-04-01

    Mathias Church of Budapest (Hungary) is an emblematic stone monument that represents various phases of constructions from Medieval period to the early 20th century. The church is found at the elevated Castle Hill and forms a landmark at the UNESCO World Heritage Site of Budapest. Its main construction material is porous Miocene limestone. Besides porous limestone travertine was also extensively used. The current study focuses on the Medieval Gate of the church which encompasses richly decorated porous limestone ornaments. The gate is now sheltered and form an interior portal of the church. It shows various forms of stone decay. The most striking one is efflorescence of salts. This feature has become more intense in the past years leading to flaking and granular disintegration of the limestone, causing damage to the monument. This study focuses on the detection of moisture content within the stone structure and its role in the salt accumulation. To obtain this goal in situ moisture measurements were made along vertical profiles by a portable moisture detector (Gann-Hydromette). It allowed outlining the moisture distribution within the studied structure. The moisture measurement was combined with sampling of salt efflorescence and porous limestone of the gate, itself. The samples were tested by optical microscopy. Conductivity, salt content and main elements were also detected from solutions. Mineralogical composition was recorded by XRD and Thermogravimetric analyses. Magnesium-sulphates were found to be the main salts responsible for damages. Besides sulphates chlorides were also detected. Gypsum was also found in the weathering crusts of the previously exposed limestone surfaces. It accumulated in black crusts but was also detected in white efflorescence and below the stone surface. The salt distribution clearly correlates with the moisture content. The financial support of NKFI Fund (ref. no. K 116532) is appreciated.

  7. Transport and retention of 14C-perfluorooctanoic acid (PFOA) in saturated limestone and sand porous media: Effects of input concentration, ionic strength and cation type

    Science.gov (United States)

    Xueyan, L.; Gao, B.; Sun, Y.; Wu, J.

    2017-12-01

    Perfluorooctanoic acid (PFOA) has been used in a wide variety of industrial and consumer product applications. PFOA has been detected around the world at ng/L to μg/L levels in groundwater, and at ng/g levels in soil.The physicochemical properties of porous media were proven to play pivotal roles in determining the transport behavior of various pollutants. It is anticipated that physicochemical properties of porous media will strongly influence the transport behavior of PFOA. In addition, previous investigations have revealed that input concentration significantly influence the transport behavior of nanoparticles and antibiotics. Thus, this study was designed experimentally and fundamentally to gain insight into transport and retention of PFOA in various porous medias at different input concentrations, solution IS and cation type. Unlike in quartz sand porous media, the BTCs in limestone porous media exhibited increasing retention rate and high degree of tailing in limestone porous media. Results showed that higher relative retention occurred in limestone porous media than in quartz sand porous media under the same solution chemistry. This result was attributed to the less negative zeta-potentials, rougher surface and larger specific surface area, and the presence of hydroxyl groups and organic matters of limestone grains. Higher ionic strength and Ca2+ had little impact on the mobility of PFOA in quartz sand porous media, but significantly enhanced the retention of PFOA in limestone porous media. The difference is likely due to the compression of the electrical double layer, and the surface-charge neutralization and cation-bridging effect of Ca2+. Higher input concentration resulted in lower relative PFOA retention in limestone porous media, but the influence were insignificant in quartz sand porous media. This effect is likely because attachment sites in limestone responced to the variety of input concentration differently than quartz.

  8. Comparison of water absorption methods: testing the water absorption of recently quarried and weathered porous limestone on site and under laboratory conditions

    Science.gov (United States)

    Rozgonyi-Boissinot, Nikoletta; Agárdi, Tamás; Karolina Cebula, Ágnes; Török, Ákos

    2017-04-01

    The water absorption of weathering sensitive stones is a critical parameter that influences durability. The current paper compares different methods of water absorption tests by using on site and laboratory tests. The aims of the tests were to assess the water absorption of un-weathered quarry stones and various weathering forms occurring on porous limestone monuments. For the tests a Miocene porous limestone was used that occurs in Central and Western Hungary and especially near and in Budapest. Besides the Hungarian occurrences the same or very similar porous limestones are found in Austria, Slovakia and in the Czech Republic. Several quarries were operating in these countries. Due to the high workability the stone have been intensively used as construction material from the Roman period onward. The most prominent monuments made of this stone were built in Vienna and in Budapest during the 18th -19th century and in the early 20th century. The high porosity and the micro-fabric of the stone make it prone to frost- and salt weathering. Three different limestone types were tested representing coarse-, medium- and fine grained lithologies. The test methods included Rilem tube (Karsten tube) tests and capillary water absorption tests. The latter methodology has been described in detail in EN 1925:2000. The test results of on-site tests of weathered porous limestone clearly show that the water absorption of dissolved limestone surfaces and crumbling or micro-cracked limestone is similar. The water absorption curves have similar inclinations marking high amount of absorbed water. To the contrary, the white weathering crusts covered stone blocks and black crusts have significantly lower water absorptions and many of these crusts are considered as very tight almost impermeable surfaces. Capillary water absorption tests in the laboratory allowed the determination of maximum water absorption of quarried porous limestone. Specimens were placed in 3 mm of water column and the

  9. Effect of the pre-treatment and the aggregate content on the adhesion strength of repair mortars on Miocene porous limestone

    Science.gov (United States)

    Szemerey-Kiss, Balázs; Török, Ákos

    2016-04-01

    The adhesion between porous limestone and newly prepared repair mortars are crucial in the preservation of historic stone structures. Besides mechanical compatibility other matches such as chemical composition and porosity are also essential, but the current research focuses on the adhesion strength of repair mortars that are used in the restoration of Hungarian porous limestone. 8 mortars (4 commercial and 4 specially prepared) were selected for the tests. Mortars with different amount of aggregate were prepared and caste to stone surface. The stone substrate was highly porous Miocene limestone. The strength was tested by standardized pull-out tests which method is commonly used for concrete testing. The limestone surfaces were either used in their natural conditions or were pre-treated (pre-wetting). The strength of the stone/mortar bond was tested. The failure mechanism was documented and various failure modes were identified. Strength test results suggest that especially pre-treatment influences strongly the pull-out strength at mortar/stone interface. Increasing aggregate content also reduces pull out strength of tested repair mortars, but at various rates depending on the mortar type. The financial support of OTKA post-doctoral grant to BSZK (reference number is: PD 112-955) and National Research, Development and Innovation (NKFI) Fund to ÁT (ref. no. K 116532) are appreciated.

  10. Hydrological characterization of cave drip waters in a porous limestone: Golgotha Cave, Western Australia

    Science.gov (United States)

    Mahmud, Kashif; Mariethoz, Gregoire; Baker, Andy; Treble, Pauline C.

    2018-02-01

    Cave drip water response to surface meteorological conditions is complex due to the heterogeneity of water movement in the karst unsaturated zone. Previous studies have focused on the monitoring of fractured rock limestones that have little or no primary porosity. In this study, we aim to further understand infiltration water hydrology in the Tamala Limestone of SW Australia, which is Quaternary aeolianite with primary porosity. We build on our previous studies of the Golgotha Cave system and utilize the existing spatial survey of 29 automated cave drip loggers and a lidar-based flow classification scheme, conducted in the two main chambers of this cave. We find that a daily sampling frequency at our cave site optimizes the capture of drip variability with the least possible sampling artifacts. With the optimum sampling frequency, most of the drip sites show persistent autocorrelation for at least a month, typically much longer, indicating ample storage of water feeding all stalactites investigated. Drip discharge histograms are highly variable, showing sometimes multimodal distributions. Histogram skewness is shown to relate to the wetter-than-average 2013 hydrological year and modality is affected by seasonality. The hydrological classification scheme with respect to mean discharge and the flow variation can distinguish between groundwater flow types in limestones with primary porosity, and the technique could be used to characterize different karst flow paths when high-frequency automated drip logger data are available. We observe little difference in the coefficient of variation (COV) between flow classification types, probably reflecting the ample storage due to the dominance of primary porosity at this cave site. Moreover, we do not find any relationship between drip variability and discharge within similar flow type. Finally, a combination of multidimensional scaling (MDS) and clustering by k means is used to classify similar drip types based on time series

  11. Hydrological characterization of cave drip waters in a porous limestone: Golgotha Cave, Western Australia

    Directory of Open Access Journals (Sweden)

    K. Mahmud

    2018-02-01

    Full Text Available Cave drip water response to surface meteorological conditions is complex due to the heterogeneity of water movement in the karst unsaturated zone. Previous studies have focused on the monitoring of fractured rock limestones that have little or no primary porosity. In this study, we aim to further understand infiltration water hydrology in the Tamala Limestone of SW Australia, which is Quaternary aeolianite with primary porosity. We build on our previous studies of the Golgotha Cave system and utilize the existing spatial survey of 29 automated cave drip loggers and a lidar-based flow classification scheme, conducted in the two main chambers of this cave. We find that a daily sampling frequency at our cave site optimizes the capture of drip variability with the least possible sampling artifacts. With the optimum sampling frequency, most of the drip sites show persistent autocorrelation for at least a month, typically much longer, indicating ample storage of water feeding all stalactites investigated. Drip discharge histograms are highly variable, showing sometimes multimodal distributions. Histogram skewness is shown to relate to the wetter-than-average 2013 hydrological year and modality is affected by seasonality. The hydrological classification scheme with respect to mean discharge and the flow variation can distinguish between groundwater flow types in limestones with primary porosity, and the technique could be used to characterize different karst flow paths when high-frequency automated drip logger data are available. We observe little difference in the coefficient of variation (COV between flow classification types, probably reflecting the ample storage due to the dominance of primary porosity at this cave site. Moreover, we do not find any relationship between drip variability and discharge within similar flow type. Finally, a combination of multidimensional scaling (MDS and clustering by k means is used to classify similar drip

  12. Prediction of effective thermal conductivity of porous consolidated media as a function of temperature: a test example of limestones

    International Nuclear Information System (INIS)

    Aurangzeb; Khan, Liaqat Ali; Maqsood, Asghari

    2007-01-01

    The thermal conductivity, thermal diffusivity and heat capacity per unit volume of sedimentary rocks (limestones) taken from Nammal Gorge sections, Western Salt Range, Pakistan, have been measured simultaneously using the transient plane source technique. The temperature dependence of thermal transport properties was studied in the temperature range 293 to 443 K. Different relations for the estimation of thermal conductivity are applied. A proposal for the prediction of thermal conductivity as a function of temperature is also given. It is observed that the values of effective thermal conductivity predicted by the proposed model are in agreement with the experimental thermal conductivity data within 8%. Furthermore, the errors in experimental calculations of thermal conductivity, thermal diffusivity and volumetric heat capacity are around 5%, 7% and 10%, respectively

  13. Influence of clay particles on Al{sub 2}O{sub 3} and TiO{sub 2} nanoparticles transport and retention through limestone porous media: measurements and mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Bayat, Ali Esfandyari, E-mail: ali.esfandiari.bayat@gmail.com; Junin, Radzuan [Universiti Teknologi Malaysia, Department of Petroleum Engineering, Faculty of Petroleum and Renewable Energy Engineering (Malaysia); Mohsin, Rahmat [Universiti Teknologi Malaysia, UTM-MPRC Institute for Oil and Gas, N29A, Lengkuk Suria (Malaysia); Hokmabadi, Mehrdad [Universiti Teknologi Malaysia, Department of Petroleum Engineering, Faculty of Petroleum and Renewable Energy Engineering (Malaysia); Shamshirband, Shahaboddin [University of Malaya, Department of Computer System and Information Technology, Faculty of Computer System and Information Technology (Malaysia)

    2015-05-15

    Utilization of nanoparticles (NPs) for a broad range of applications has caused considerable quantities of these materials to be released into the environment. Issues of how and where the NPs are distributed into the subsurface aquatic environments are questions for those in environmental engineering. This study investigated the influence of three abundant clay minerals namely kaolinite, montmorillonite, and illite in the subsurface natural aquatic systems on the transport and retention of aluminum oxide (Al{sub 2}O{sub 3}, 40 nm) and titanium dioxide (TiO{sub 2}, 10–30 nm) NPs through saturated limestone porous media. The clay concentrations in porous media were set at 2 and 4 vol% of the holder capacity. Breakthrough curves in the columns outlets were measured using a UV–Vis spectrophotometer. It was found that the maximum NPs recoveries were obtained when there was no clay particle in the porous medium. On the other hand, increase in concentration of clay particles has resulted in the NPs recoveries being significantly declined. Due to fibrous structure of illite, it was found to be more effective for NPs retention in comparison to montmorillonite and kaolinite. Overall, the position of clay particles in the porous media pores and their morphologies were found to be two main reasons for increase of NPs retention in porous media.

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

    International Nuclear Information System (INIS)

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

    2014-01-01

    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

  15. Fluids transfer in porous media, the case of carbonates and clay/limestone interfaces. Integrated study of petrophysical, sedimentology and microstructures.The case of two carbonates: the case of two carbonates the Oolithe Blanche from the Paris Basin and the Globigerina Limestone of maltese islands

    International Nuclear Information System (INIS)

    Casteleyn, Lisa

    2011-01-01

    Geological storage is now considered as a technical solution for CO_2 storage and nuclear waste management (for high-level and intermediate-level long-lived radioactive waste). A geological storage is a long term project which implies a particular protocol in order to better determine and to better understand the host rock, especially in terms of transport mechanisms. The geological formations studied are chosen in function of their storage capacity because gas storage or nuclear waste storage do not need the same requirements. In case of CO_2 storage, the host formation must provide good reservoir properties in order to facilitate the injection. Here, the safety of the storage is guaranteed by traps (structural, residual, mineral) and by the presence of a cap rock. Concerning nuclear waste storage, the host must retain at best the potential radioactive fluids and gas leaks, and this is the reason why storage sites are studied within low porous and low permeable formation, like argillite organelles. The work presented in the PhD thesis is related to two storage projects. The first one is focused on the petrophysical study of a potential host for CO_2 storage in the Paris Basin, the 'Oolithe Blanche' carbonate formation. The second project is an analogue study of the sedimentary structure explored in the Meuse/Haute-Marne laboratory. This laboratory is studied by ANDRA to be the first nuclear waste storage in a deep geological formation in France. The analogue was found in maltese archipelagos, which presents almost the same tabular structure as the one observed in the Meuse/Haute-Marne laboratory: limestone/clay/limestone affected by a weak tectonic deformation. In the first part, the Oolithe Blanche Formation study allowed to determine the reservoir properties of the three principals facies of the formation. This study was realized on plugs sampled on quarries in Burgundy (France). Those facies are characterized by different environmental processes and deposit

  16. Direct Sulfation of Limestone

    DEFF Research Database (Denmark)

    Hu, Guilin; Dam-Johansen, Kim; Wedel, Stig

    2007-01-01

    The direct sulfation of limestone was studied in a laboratory fixed-bed reactor. It is found that the direct sulfation of limestone involves nucleation and crystal grain growth of the solid product (anhydrite). At 823 K and at low-conversions (less than about 0.5 %), the influences of SO2, O-2...... and CO2 on the direct sulfation of limestone corresponds to apparent reaction orders of about 0.2, 0.2 and -0.5, respectively. Water is observed to promote the sulfation reaction and increase the apparent reaction orders of SO2 and O-2. The influence of O-2 at high O-2 concentrations (> about 15...... %) becomes negligible. In the temperature interval from 723 K to 973 K, an apparent activation energy of about 104 kJ/mol is observed for the direct sulfation of limestone. At low temperatures and low conversions, the sulfation process is most likely under mixed control by chemical reaction and solid...

  17. Initial kinetics of the direct sulfation of limestone

    DEFF Research Database (Denmark)

    Hu, Guilin; Shang, Lei; Dam-Johansen, Kim

    2008-01-01

    The initial kinetics of direct sulfation of Faxe Bryozo, a porous bryozoan limestone was studied in the temperature interval from 873 to 973 K in a pilot entrained flow reactor with very short reaction times (between 0.1 and 0.6 s). The initial conversion rate of the limestone - for conversions...... less than 0.3% - was observed to be significantly promoted by higher SO2 concentrations and lower CO2 concentrations, whereas 02 showed negligible influence. A mathematical model for the sulfation of limestone involving chemical reaction at calcite grain surfaces and solid-state diffusion of carbonate...... ions in calcite grains is established. The validity of the model is limited to the initial sulfation period, in which nucleation of the solid product calcium sulphate is not started. This theoretical reaction-diffusion model gives a good simulation of the initial kinetics of the direct sulfation...

  18. Modeling contaminant plumes in fractured limestone aquifers

    DEFF Research Database (Denmark)

    Mosthaf, Klaus; Brauns, Bentje; Fjordbøge, Annika Sidelmann

    Determining the fate and transport of contaminant plumes from contaminated sites in limestone aquifers is important because they are a major drinking water resource. This is challenging because they are often heavily fractured and contain chert layers and nodules, resulting in a complex transport...... model. The paper concludes with recommendations on how to identify and employ suitable models to advance the conceptual understanding and as decision support tools for risk assessment and the planning of remedial actions....... behavior. Improved conceptual models are needed for this type of site. Here conceptual models are developed by combining numerical models with field data. Several types of fracture flow and transport models are available for the modeling of contaminant transport in fractured media. These include...... the established approaches of the equivalent porous medium, discrete fracture and dual continuum models. However, these modeling concepts are not well tested for contaminant plume migration in limestone geologies. Our goal was to develop and evaluate approaches for modeling the transport of dissolved contaminant...

  19. Limestone valib eetilisi firmasid / Virge Lahe

    Index Scriptorium Estoniae

    Lahe, Virge

    2008-01-01

    Endised Hansapanga investeerimisfondide analüütikud hakkavad läbi Limestone fondide pakkuma sotsiaalselt vastutustundlikku investeerimist (Socially Responsible Investing). Kommenteerivad Art Lukas ja Silver Vohu. Vt. samas: Limestone Investment Management AS

  20. CALCIUM CARBONATE DISSOLUTION RATE IN LIMESTONE CONTACTORS

    Science.gov (United States)

    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...

  1. Boiling in porous media

    International Nuclear Information System (INIS)

    1998-01-01

    This conference day of the French society of thermal engineers was devoted to the analysis of heat transfers and fluid flows during boiling phenomena in porous media. This book of proceedings comprises 8 communications entitled: 'boiling in porous medium: effect of natural convection in the liquid zone'; 'numerical modeling of boiling in porous media using a 'dual-fluid' approach: asymmetrical characteristic of the phenomenon'; 'boiling during fluid flow in an induction heated porous column'; 'cooling of corium fragment beds during a severe accident. State of the art and the SILFIDE experimental project'; 'state of knowledge about the cooling of a particulates bed during a reactor accident'; 'mass transfer analysis inside a concrete slab during fire resistance tests'; 'heat transfers and boiling in porous media. Experimental analysis and modeling'; 'concrete in accidental situation - influence of boundary conditions (thermal, hydric) - case studies'. (J.S.)

  2. Residual CO2 trapping in Indiana limestone.

    Science.gov (United States)

    El-Maghraby, Rehab M; Blunt, Martin J

    2013-01-02

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

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

    Science.gov (United States)

    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.

  4. The behavior limestone under explosive load

    Science.gov (United States)

    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.

  5. Evaluation of Different Modeling Approaches to Simulate Contaminant Transport in a Fractured Limestone Aquifer

    Science.gov (United States)

    Mosthaf, K.; Rosenberg, L.; Balbarini, N.; Broholm, M. M.; Bjerg, P. L.; Binning, P. J.

    2014-12-01

    It is important to understand the fate and transport of contaminants in limestone aquifers because they are a major drinking water resource. This is challenging because they are highly heterogeneous; with micro-porous grains, flint inclusions, and being heavily fractured. Several modeling approaches have been developed to describe contaminant transport in fractured media, such as the discrete fracture (with various fracture geometries), equivalent porous media (with and without anisotropy), and dual porosity models. However, these modeling concepts are not well tested for limestone geologies. Given available field data and model purpose, this paper therefore aims to develop, examine and compare modeling approaches for transport of contaminants in fractured limestone aquifers. The model comparison was conducted for a contaminated site in Denmark, where a plume of a dissolved contaminant (PCE) has migrated through a fractured limestone aquifer. Multilevel monitoring wells have been installed at the site and available data includes information on spill history, extent of contamination, geology and hydrogeology. To describe the geology and fracture network, data from borehole logs was combined with an analysis of heterogeneities and fractures from a nearby excavation (analog site). Methods for translating the geological information and fracture mapping into each of the model concepts were examined. Each model was compared with available field data, considering both model fit and measures of model suitability. An analysis of model parameter identifiability and sensitivity is presented. Results show that there is considerable difference between modeling approaches, and that it is important to identify the right one for the actual scale and model purpose. A challenge in the use of field data is the determination of relevant hydraulic properties and interpretation of aqueous and solid phase contaminant concentration sampling data. Traditional water sampling has a bias

  6. French Foodscapes

    DEFF Research Database (Denmark)

    Hedegaard, Liselotte

    By exploring how local and regional products and uses of food interact with the changes in the French cuisine over time, this paper seeks to retrace the history of the French meal through meanings of place and time, terroir and savoir-faire. The study will be based on sources from early modern/modern history...... the destructuralisation of eating habits have been raised since the 1980s, but numerous studies emphasise that the traditional French meal is still playing an important role in everyday life in France. Despite regional variations, the general view of the structure of a traditional French meal as based on the succession...... of flavours and the accordance with wines is widespread. Such a comprehension means giving precedence to gastronomic reasons for determining the order of dishes. However, the French meal has not always been composed in the way it is today and the reasons for the composition have not always been gastronomic...

  7. French Courses

    CERN Multimedia

    2012-01-01

    General and Professional French Courses These courses are open to all persons working on the CERN site, and to their spouses. The next session will take place from 28 January to 5 April 2013. Oral Expression This course is aimed for students with a good knowledge of French who want to enhance their speaking skills. Speaking activities will include discussions, meeting simulations, role-plays etc. The next session will take place from 28 January to 5 April 2013. Writing professional documents in French These courses are designed for non-French speakers with a very good standard of spoken French. The next session will take place from 28 January to 5 April 2013. For registration and further information on the courses, please consult our Web pages or contact Kerstin Fuhrmeister.

  8. French Training

    CERN Multimedia

    Françoise Benz

    2003-01-01

    General and Professional French Courses The next session will take place: from 13 October to 19 December 2003. These courses are open to all persons working on the CERN site, and to their spouses. For registration and further information on the courses, please consult our Web pages or contact Mrs. Fontbonne: Tel. 72844. Writing Professional Documents in French This course is designed for people with a good level of spoken French. Duration: 30 hours Price: 660 CHF (for 8 students) For further information and registration, please consult our Web pages or contact Mrs. Fontbonne: Tel. 72844. Language Training Françoise Benz Tel.73127 language.training@cern.ch

  9. French courses

    CERN Document Server

    HR Department

    2012-01-01

    General and Professional French Courses The next session will take place from 2nd May to 6th July 2012. These courses are open to all persons working on the CERN site, and to their spouses. For registration and further information on the courses, please consult our Web pages or contact Kerstin Fuhrmeister.   Oral Expression This course is aimed for students with a good knowledge of French who want to enhance their speaking skills. Speaking activities will include discussions, meeting simulations, role-plays etc. Suitable candidates should contact Kerstin Fuhrmeister (70896) in order to arrange an appointment for a test. The next session will take place from 2nd May to 6th July 2012.   Writing professional documents in French These courses are designed for non-French speakers with a very good standard of spoken French. Suitable candidates should contact Kerstin Fuhrmeister (70896) in order to arrange an appointment for a test. The next session will take place from 2nd May to ...

  10. French courses

    CERN Document Server

    2013-01-01

    General and Professional French Courses The next session will take place from 29 April to 5 July 2013. These courses are open to all persons working on the CERN site, and to their spouses. For registration and further information on the courses, please consult our Web pages or contact Kerstin Fuhrmeister (kerstin.fuhrmeister@cern.ch). Oral Expression This course is aimed for students with a good knowledge of French who want to enhance their speaking skills. Speaking activities will include discussions, meeting simulations, role-plays etc. Suitable candidates should contact Kerstin Fuhrmeister (70896) in order to arrange an appointment for a test. The next session will take place from 29 April to 5 July 2013. Writing professional documents in French These courses are designed for non-French speakers with a very good standard of spoken French. Suitable candidates should contact Kerstin Fuhrmeister (70896) in order to arrange an appointment for a test. The next session will take place from 29 April to 5 July...

  11. Reaction between Hydrogen Sulfide and Limestone Calcines

    Czech Academy of Sciences Publication Activity Database

    Hartman, Miloslav; Svoboda, Karel; Trnka, Otakar; Čermák, Jiří

    2002-01-01

    Roč. 41, č. 10 (2002), s. 2392-2398 ISSN 0888-5885 R&D Projects: GA AV ČR IAA4072711; GA AV ČR IAA4072801 Keywords : hydrogen sulfide * limestone calcines * desulfurization Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.247, year: 2002

  12. Hydrogen Chloride Reaction with Lime and Limestone

    DEFF Research Database (Denmark)

    Erik Weinell, Claus; Jensen, Peter I.; Dam-Johansen, Kim

    1992-01-01

    The capacity of solid slaked lime and limestone for binding HCl from a gas phase has been investigated in the temperature range 60-1000 °C. The binding capacity is largest in the range 500-600 °C. However, for slaked lime in the presence of water, a large binding capacity is observed also below 150...

  13. Neutron activation analysis of limestone objects

    International Nuclear Information System (INIS)

    Meyers, P.; Van Zelst, L.

    1977-01-01

    The elemental composition of samples from limestone objects were determined by neutron activation analysis to investigate whether this technique can be used to distinguish between objects made of limestone from different sources. Samples weighing between 0.2-2 grams were obtained by drilling from a series of ancient Egyptian and medieval Spanish objects. Analysis was performed on aliquots varying in weight from 40-100 milligrams. The following elements were determined quantitatively: Na, K, Rb, Cs, Ba, Sc, La, Ce, Sm, Eu, Hf, Th, Ta, Cr, Mn, Fe, Co and Zn. The data on Egyptian limestones indicate that, because of the inhomogeneous nature of the stone, 0.2-2 gram samples may not be representative of an entire object. Nevertheless, multivariate statistical methods produced a clear distinction between objects originating from the Luxor area (ancient Thebes) and objects found north of Luxor. The Spanish limestone studied appeared to be more homogeneous. Samples from stylistically related objects have similar elemental compositions while relative large differences were observed between objects having no relationship other than the common provenance of medieval Spain. (orig.) [de

  14. Access French

    CERN Document Server

    Grosz, Bernard

    2014-01-01

    Access is the major new language series designed with the needs of today's generation of students firmly in mind. Whether learning for leisure or business purposes or working towards a curriculum qualification, Access French is specially designed for adults of all ages and gives students a thorough grounding in all the skills required to understand, speak, read and write contemporary French from scratch. The coursebook consists of 10 units covering different topic areas, each of which includes Language Focus panels explaining the structures covered and a comprehensive glossary. Learning tips

  15. The use of Limestone Powder as an Alternative Cement Replacement

    African Journals Online (AJOL)

    user

    focused on the effects of limestone on the cement ... construction materials in Ethiopia is increasing .... Findings of research works on the strength reveals ... This CEN standard sand is delivered ... control mix made without limestone fines.

  16. Kinetic Study of Calcination of Jakura Limestone Using Power Rate ...

    African Journals Online (AJOL)

    National Research Institute for Chemical Technology, P.M. B 1052, Zaria, ... calcination of Jakura limestone was also found to be first order reaction with respect to CaCO3 ... Keywords: Jakura, limestone, calcination, kinetics, power law model.

  17. The effect of limestone aggregate porosity and saturation degree on the interfacial zone

    International Nuclear Information System (INIS)

    Nguyen, T.D.; Le Saout, G.; Devillers, P.; Garcia-Diaz, E.

    2015-01-01

    The recycling of concrete wastes concerns the nuclear industry as many nuclear facilities will have to be dismantled and the reduction and reuse of the decommissioning concrete wastes in order to minimize the total waste volume is a key issue. The recycled aggregates have the potential to replace natural resources however it is necessary to assess the effect of recycled aggregates on the final concrete. One important issue to be addressed to achieve the required mechanical properties is the water absorption of the recycled aggregates. As a first step, we have used in this study limestone aggregates with different porosities (total porosity from 2 to 20 %) and have investigated the influence of the porosity and the initial saturation degree of these aggregates on the porosity of the interfacial transition zone (ITZ) using scanning electron microscope. The equation of Feret for the strength-porosity relationship of our mortars was applied σ = K(100-p) 2 where σ is the compressive strength in MPa, p is the capillary pore volume in % and K a constant. Aggregates with lower porosity follow the same law characterized by a K value higher than the value for the more porous aggregate law. The K parameter is not dependent of the humidity degree of the aggregate: for a given aggregate, family mortars made with dry and wet aggregate follow the same law. But for porous aggregates as the meso-porosity of the ITZ for a given time of hydration is higher for mortars made with wet aggregates, the compressive strength of these mortars is less than those of mortars made with dry aggregates. Contrary to the low porous aggregate, it was not possible for porous limestone aggregates, and with a calculation based on the saturated surface dry state as reference state to obtain the same net water to cement ratio with wet and dry aggregates. This study reflects the difficulty to control the amount of efficient water in concrete when using porous aggregates and its influence on compressive

  18. French regulations

    International Nuclear Information System (INIS)

    Ballereau, P.

    1998-01-01

    In this issue are given the new French regulations relative to radiation protection of temporary personnel, the licensing to release gaseous and liquid wastes and the licensing granted to thirty two laboratories using beta and gamma decay radioisotopes. (N.C.)

  19. Effect of limestone particle size on bone quality characteristics of ...

    African Journals Online (AJOL)

    A study was conducted to determine the effect of different limestone particle sizes in layer diets on bone quality characteristics at end-of-lay hens. Calcitic limestone (360 g Ca/kg DM) that is extensively used in commercial poultry diets was obtained from a specific South African source. Limestone particles were graded as ...

  20. Face logging in Copenhagen Limestone, Denmark

    DEFF Research Database (Denmark)

    Jakobsen, Lisa; Foged, Niels Nielsen; Erichsen, Lars

    2015-01-01

    tunnel in Copenhagen more than 2.5 km face logs were made in 467 locations at underground stations, shafts, caverns and along bored tunnels. Over 160 geotechnical boreholes, many with geophysical logging were executed prior to construction works. The bedrock consists of Paleogene "Copenhagen limestone......The requirement for excavation support can be assessed from face logging. Face logs can also improve our knowledge of lithological and structural conditions within bedrock and supplement information from boreholes and geophysical logs. During the construction of 8 km metro tunnel and 4 km heating....... The induration degrees recorded in face logs and boreholes are compared and correlated. Distinct geophysical log markers are used to divide the limestone into three units. These marker horizons are correlated between face logs and geotechnical boreholes. A 3D model of the strength variations recorded within...

  1. Porous carbons

    Indian Academy of Sciences (India)

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

    Abstract. Carbon in dense as well as porous solid form is used in a variety of applications. Activated porous carbons are made through pyrolysis and activation of carbonaceous natural as well as synthetic precursors. Pyrolysed woods replicate the structure of original wood but as such possess very low surface areas and ...

  2. Plant Guide: Limestone hawksbeard: Crepis intermedia

    Science.gov (United States)

    L. St. John; D. Tilley

    2012-01-01

    Sunflower family (Asteraceae). Limestone hawksbeard is a native perennial forb with one or two stems arising from a taproot. Plants are 30-70cm tall and basal leaves are 10-40 cm long, pinnatifid, with a fairly broad, undivided midstrip and entire or dentate segments. Plants are densely or sparsely gray-tomentulose. There are 10-60 heads per plant that are 7-12...

  3. French Customs

    CERN Multimedia

    GS Department

    2010-01-01

    Please note that the French Customs (initially located in Building 904, Prévessin) are now located in Ferney-Voltaire (FR): Mrs Catherine NEUVILLE Douane de Ferney-Voltaire Rue de Genève F – 01210 Ferney-Voltaire Phone : 33 4 50 40 51 42 Email : catherine.neuville@douane.finances.gouv.fr Tom Wegelius Tel: 79947 Logistics and Site Services

  4. French visas

    CERN Multimedia

    2007-01-01

    The French Ministry of Foreign Affairs (hereinafter "MAE") has informed CERN of the following new regulations governing the visas required when submitting requests for French legitimation documents (cf. in particular paragraph b) below concerning the facilities recently granted to certain categories of persons who are not nationals of Switzerland or of a member state of the European Economic Area). This notification replaces that which appeared in Bulletin No.19/2006 (ref. CERN/DSU-DO/RH/13173/Rev.). 1. Special residence permit ("Titre de séjour special") To qualify for a special residence permit from the MAE, persons who are not nationals of Switzerland or of a member state of the European Economic Area (hereinafter "EEA") must present the following upon arrival at CERN: a)\teither a “D”-type (long-stay) French visa marked “carte PROMAE à solliciter à l’arrivée”, even if they are not subject to the requirement to obtain an entrance and short-stay visa in France...

  5. Limestone quarrying and quarry reclamation in Britain

    Science.gov (United States)

    Gunn, J.; Bailey, D.

    1993-06-01

    Limestones have been worked for many thousands of years — initially for building stone and agricultural lime and more recently for a wide range of construction and industrial uses. In most industrialized countries limestone quarries represent the most visually obvious and, in both process and landform terms, the most dramatic anthropogenic impact on karst terrain. However, quarrying has, to date, received surprisingly little attention from karst scientists. Research in the English Peak District suggested that the postexcavation evolution of quarried limestone rock faces was in part a result of the methods used in their excavation, and this led to the development of a technique designed to reduce the visual and environmental impacts of modern quarries by “Landform replication. ” This involves the use of controlled “restoration blasting” techniques on quarried rock slopes to construct a landform sequence similar to that in the surrounding natural landscape. The constructed landforms are then partially revegetated using appropriate wildflower, grass, and/or tree species.

  6. French slanguage

    CERN Document Server

    Ellis, Michael

    2012-01-01

    With this fun visual guide, simply follow the illustrated prompts and read the English words out loud: soon you'll be speaking French! Ask how someone is doing: "Comet Haley View" or say thank you very much: "Mare See Bow Cool." The simple icons are easy to follow and this pocket-sized guide is easy to carry with you. It will give you the basic phrases you need to get around while traveling, whether asking directions, ordering food at a restaurant, or shopping. But most of all, it's just plain fun!

  7. French training

    CERN Multimedia

    2007-01-01

    The next session will take place from 29 January to 30 March 2007. These courses are open to all persons working on the CERN site, and their spouses. For registration and further information on the courses, please consult our Web pages: http://cern.ch/Training or contact Mrs. Benz: tel. 73127. Writing Professional Documents in French The next session will take place from 29 January to 30 March 2007. This course is designed for people with a good level of spoken French. Duration: 30 hours Price: 660 CHF (for 8 students) For further information and registration, please consult our Web pages: http://cern.ch/Training or contact Mrs. Benz: tel. 73127. Writing Professional Documents in English The next session will take place from January to June 2007 (break at Easter). This course is designed for people with a good level of spoken English. Duration: 30 hours Price: 660 CHF (for 8 students) Timetable will be fixed after discussion with the students. For further information and registration, please consu...

  8. Rock mass characterization for tunnels in the Copenhagen limestone

    DEFF Research Database (Denmark)

    Foged, Niels Nielsen; Jakobsen, Lisa; Jackson, Peter

    2007-01-01

    Tunnels in Copenhagen are drilled through highly anisotropic limestone comprising alternating strongly lithified and less lithified parts. The mass quality of the limestone is usually defined from fracture spacing registered in core samples. The deposit is, however, affected destructively by dril...... by drilling activity yielding a low Rock Quality Designation RQD. In-situ observations of the limestone in excavations or televiewer logs reveal only few natural discontinuities compared to core logging, indicating a very good suitability for tunneling....

  9. Mechanical Analysis Of Limestone In Jaya, Lhong, And Lhoknga

    Directory of Open Access Journals (Sweden)

    Raihan .

    2012-09-01

    Full Text Available Research about mechanical analysis of limestone in District Jaya, Lhong, and Lhoknga has been done from Dec. 2011 to Mei 2012. This study aim is to classify the limestones based on physical and mechanical tests as well as identify opportunities limestone utilization in accordance with the SII 0378-80 as a condition of quality natural stone for building. Research have been done by testing compressive strength, modulus Young, wear, specific gravity, porosity, and absorption. The result shows that the limestones are qualified natural stone for building the foundation, curbstone, stone and ornamental stone or paste.

  10. The Influence of Combustion-derived pollutants on limestone deterioration

    DEFF Research Database (Denmark)

    Johnson, J.B.; Montgomery, Melanie; Thompson, G.E.

    1996-01-01

    The wet deposition of combustion-derived atmospheric pollutant species, on to freshly cut or diesel-smoked Portland and Monks Park limestone and marble samples, was carried out in a laboratory 'wetting and drying' salt spray chamber for 84 days. Along with the effect of CO2-equilibrated de...... limestones, respectively. Thus the water and hydrogen ion loading effects are significant, as well as the limestone type, but the nature of the anion is not, under the given wetting and drying regime. Further work showed that the increased resistance of marble over that of limestone, to calcium loss...

  11. 3D mapping of water in oolithic limestone at atmospheric and vacuum saturation using X-ray micro-CT differential imaging

    Energy Technology Data Exchange (ETDEWEB)

    Boone, M.A., E-mail: marijn.boone@ugent.be [Department of Geology and Soil Science—UGCT, Ghent University, Krijgslaan 281 S8, 9000 Ghent (Belgium); Unit Sustainable Materials Management, VITO, Boerentang 200, 2400 Mol (Belgium); De Kock, T.; Bultreys, T. [Department of Geology and Soil Science—UGCT, Ghent University, Krijgslaan 281 S8, 9000 Ghent (Belgium); De Schutter, G. [Magnel Laboratory for Concrete Research, Department of Structural Engineering, Ghent University, Technologiepark-Zwijnaarde 904, 9052 Ghent (Belgium); Vontobel, P. [Spallation Neutron Source Division, Paul Scherrer Institute (PSI), 5232 Villigen (Switzerland); Van Hoorebeke, L. [Department of Physics and Astronomy—UGCT, Ghent University, Proeftuinstraat 86, 9000 Ghent (Belgium); Cnudde, V. [Department of Geology and Soil Science—UGCT, Ghent University, Krijgslaan 281 S8, 9000 Ghent (Belgium)

    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

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

    Science.gov (United States)

    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,...

  13. Catalytic and Gas-Solid Reactions Involving HCN over Limestone

    DEFF Research Database (Denmark)

    Jensen, Anker; Johnsson, Jan Erik; Dam-Johansen, Kim

    1997-01-01

    In coal-fired combustion systems solid calcium species may be present as ash components or limestone added to the combustion chamber. In this study heterogeneous reactions involving HCN over seven different limestones were investigated in a laboratory fixed-bed quartz reactor at 873-1,173 K...

  14. Effect of limestone particle size on egg production and eggshell ...

    African Journals Online (AJOL)

    Different limestone particle sizes had no effect on any of the tested egg production and eggshell quality parameters. These results suggested that larger particles limestone are not necessarily essential to provide sufficient Ca2+ to laying hens for egg production and eggshell quality at end-of-lay, provided that the dietary Ca ...

  15. French Teaching Aids.

    Science.gov (United States)

    Miller, J. Dale

    Supplementary teaching materials for French language programs are presented in this text. Primarily intended for secondary school students, the study contains seven units of material. They include: (1) French gestures, (2) teaching the interrogative pronouns, (3) French cuisine, (4) recreational learning games, (5) French-English cognates, (6)…

  16. Petrophysical and transport parameters evolution during acid percolation through structurally different limestones

    Science.gov (United States)

    Martinez Perez, Laura; Luquot, Linda

    2017-04-01

    Processes affecting geological media often show complex and unpredictable behavior due to the presence of heterogeneities. This remains problematic when facing contaminant transport problems, in the CO2 storage industry or dealing with the mechanisms underneath natural processes where chemical reactions can be observed during the percolation of rock non-equilibrated fluid (e.g. karst formation, seawater intrusion). To understand the mechanisms taking place in a porous medium as a result of this water-rock interaction, we need to know the flow parameters that control them, and how they evolve with time as a result of that concurrence. This is fundamental to ensure realistic predictions of the behavior of natural systems in response of reactive transport processes. We investigate the coupled influence of structural and hydrodynamic heterogeneities in limestone rock samples tracking its variations during chemical reactions. To do so we use laboratory petrophysical techniques such as helium porosimetry, gas permeability, centrifugue, electrical resistivity and sonic waves measurements to obtain the parameters that characterize flow within rock matrix (porosity, permeability, retention curve and pore size distribution, electrical conductivity, formation factor, cementation index and tortuosity) before and after percolation experiments. We built an experimental setup that allows injection of acid brine into core samples under well controlled conditions, monitor changes in hydrodynamic properties and obtain the chemical composition of the injected solution at different stages. 3D rock images were also acquired before and after the experiments using a micro-CT to locate the alteration processes and perform an acurate analysis of the structural changes. Two limestones with distinct textural classification and thus contrasting transport properties have been used in the laboratory experiments: a crinoid limestone and an oolithic limestone. Core samples dimensions were 1 inch

  17. Field trial of a pulsed limestone diversion well

    Science.gov (United States)

    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.

  18. High Resolution ground penetrating radar (GPR) measurements at the laboratory scale to model porosity and permeability in the Miami Limestone in South Florida.

    Science.gov (United States)

    Mount, G. J.; Comas, X.

    2015-12-01

    Subsurface water flow within the Biscayne aquifer is controlled by the heterogeneous distribution of porosity and permeability in the karst Miami Limestone and the presence of numerous dissolution and mega-porous features. The dissolution features and other high porosity areas can create preferential flow paths and direct recharge to the aquifer, which may not be accurately conceptualized in groundwater flow models. As hydrologic conditions are undergoing restoration in the Everglades, understanding the distribution of these high porosity areas within the subsurface would create a better understanding of subsurface flow. This research utilizes ground penetrating radar to estimate the spatial variability of porosity and dielectric permittivity of the Miami Limestone at centimeter scale resolution at the laboratory scale. High frequency GPR antennas were used to measure changes in electromagnetic wave velocity through limestone samples under varying volumetric water contents. The Complex Refractive Index Model (CRIM) was then applied in order to estimate porosity and dielectric permittivity of the solid phase of the limestone. Porosity estimates ranged from 45.2-66.0% from the CRIM model and correspond well with estimates of porosity from analytical and digital image techniques. Dielectric permittivity values of the limestone solid phase ranged from 7.0 and 13.0, which are similar to values in the literature. This research demonstrates the ability of GPR to identify the cm scale spatial variability of aquifer properties that influence subsurface water flow which could have implications for groundwater flow models in the Biscayne and potentially other shallow karst aquifers.

  19. Strengthening of limestone by the impregnation - gamma irradiation method. Results of tests

    International Nuclear Information System (INIS)

    Ramiere, R.; Tassigny, C. de

    1975-04-01

    The method developed by the Centre d'Etudes Nucleaires de Grenoble (France) strengthens the stones by impregnation with a styrene resin/liquid polystyrene mixture followed by polymerization under gamma irradiation. This method is applicable to stones which can be taken into the laboratory for treatment. The increase in strength of 6 different species of French limestone has been quantitatively recorded. The following parameters were studied: possibility of water migration inside the stones, improvements of the mechanical properties of the impregnated stone, standing up to freeze-thaw conditions and artificial ageing of the stones which causes only minor changes in the appearance of the stone and a negligible decrease in weight [fr

  20. French grammar for dummies

    CERN Document Server

    Mazet, Veronique

    2013-01-01

    The easy way to master French grammar French Grammar For Dummies is a logical extension and complement to the successful language learning book, French For Dummies. In plain English, it teaches you the grammatical rules of the French language, including parts of speech, sentence construction, pronouns, adjectives, punctuation, stress and verb tenses, and moods. Throughout the book, you get plenty of practice opportunities to help you on your goal of mastering basic French grammar and usage. Grasp the grammatical rules of French including parts of speech, sentenc

  1. Diagenesis of polymineralic temperate limestones in a cyclothemic sedimentary succession, eastern North Island, New Zealand

    International Nuclear Information System (INIS)

    Haywick, D.W.

    2004-01-01

    Temperate carbonate petrofacies (calcarenite and coquina) in the Pliocene-Pleistocene Petane Group of eastern North Island, New Zealand, are dominated by aragonite faunas consisting primarily of bivalves and gastropods. Unlike calcite-dominated temperate limestones, these polymineralic carbonates have undergone extensive early diagenetic alteration including extensive calcite cementation induced by aragonite dissolution. Marine cementation (type 1: pore-lining, bladed calcite) was isolated to biogenic pores. It predated glauconite and may have been precipitated as low-magnesium calcite, possibly in marine phreatic environments during sea-level transgressions. Four phases of calcite cement with varying but definitive degrees of meteoric influence occur in the Petane Group. Type 2 (ferroan scalenohedral calcite) was the initial pore-filling cement and precipitated from reduced pore fluids in a phreatic environment, possibly during or soon after the transition from marine to meteoric diagenesis. Type 3 (moderately ferroan drusy) calcite and type 4 (non-ferroan drusy) calcite were sequentially precipitated during meteoric conditions from pore waters that changed from reducing to oxidising. Type 5 (sinter) cements comprise several forms precipitated during vadose meteoric diagenesis, the final meteoric phase of alteration in the Petane Group. Ferroan calcite cementation of silt matrix in coquina limestones overlain by terrigenous silt (type 6: matrix cement) probably occurred simultaneously with type 2/3 pore-filling phases. A similar ferroan to moderately ferroan to non-ferroan suite of drusy calcite cements also lithified concretions in non-carbonate (siliciclastic sand) facies in the Petane Group, but only after the onset of compaction. Extensive skeletal diagenesis (stabilisation of magnesium calcite allochems, dissolution/recrystallisation of aragonite) occurred during type 3 and 4 cementation phases. Diagenesis in the Petane Group was stratigraphically influenced

  2. Electrical conductivity of sandstone, limestone, and granite

    Energy Technology Data Exchange (ETDEWEB)

    Duba, A.; Piwinskii, A.J.; Santor, M.; Weed, H.C.

    1978-01-01

    The electrical conductivity of cylindrical cores of Westerly granite, Indiana limestone and Nugget, St Peter and Kayenta sandstones was measured at about 25/sup 0/C in vacuo, in air, and after saturation in distilled water, tap water, and 0.1 M NaCl solution. The three-electrode technique with a guard ring and the two-electrode technique without a guard ring were used. Core aspect ratio over the range of 2.00 to 0.25, as well as frequency over the range of 50 Hz to 10 kHz, influences the conductivity of all rocks, especially those measured in vacuo. Measurements from water-saturated samples using a guard ring are not appreciably different from those obtained without a guard ring. The conductivity of rocks saturated in 0.1 M NaCl solution changes least with a change in aspect ratio; for these rocks a linear relationship, known as Archie's Law, exists between log porosity and log conductivity. No simple correlation was found between those factors in rocks saturated with tap or distilled water. Thus, it appears Archie's Law is of questionable value for correlating laboratory data from rocks saturated with low-conductivity fluids.

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

    International Nuclear Information System (INIS)

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

    1998-01-01

    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

  4. Improving DMS 9210 requirements for limestone rock asphalt - final report.

    Science.gov (United States)

    2015-03-01

    Limestone Rock Asphalt (LRA) mixtures have been produced and placed for several decades using : specification requirements currently listed under DMS 9210. Several districts have had placement issues : and premature failures at the beginning of 2010....

  5. Limestone doses affecting mineral contents in tropical grass forage

    International Nuclear Information System (INIS)

    Armelin, M.J.A.; Saiki, M.

    2005-01-01

    Field trial was performed at the experimental farm of Southeast Embrapa Cattle, Sao Carlos - SP, Brazil, on a 16 year old Brachiaria decumbens pasture, grown on a distrophic Hapludox (Oxisol), recovered by the use of limestone and fertilizer. The experiments were carried out in random blocks, with 6 replications and 5 treatments. The 100 m 2 blocks were established in the pasture. Each block received a sequence of limestone doses of 0, 1, 2, 4 and 8 t/ha. The forage samples were taken one year after limestone application on soil surface. Instrumental neutron activation analysis (INAA) followed by gamma-ray spectrometry was the analytical method used to determine mineral contents. The statistical analysis showed a negative linear correlation of Br, Co, Cr, Mn and Zn contents in forage with the limestone doses, while the uptake of Mg was affected in a positive way. (author)

  6. Combined Neutron and X-Ray Radiographic/Tomographic Analysis of Dissolution Limestones under Acidic Conditions

    Science.gov (United States)

    Anovitz, L. M.; Cole, D. R.; Hussey, D. S.; LaManna, J.; Swift, A.; Jacobson, D. L.

    2016-12-01

    Carbon dioxide capture and sequestration in deep geological formations is an important option for reducing greenhouse gas emissions. While the importance of porosity and pore-evolution has long been recognized, the evolution of porosity and permeability in reactive carbonates exposed to CO2-loaded brines is not well constrained. A typical pH range for CO2-acidified brine is 3 to 4.5 depending on alkalinity. This represents a substantial perturbation of typical brines that range from pH 6 to 8. The key questions include how accessible are the pores to fluid transport and how does the pore network evolve as the matrix reacts with the acidic solution? Limestones and dolostones contain nano- to macroscale porosity comprised of cracks, grain boundaries, fluid inclusions, single pores, vugs and networks of pores of random shapes and orientations. Accessible, interconnected pores may act as pore throats, constraining overall flow and are the most likely locations for extensive rock alteration. Neutron imaging is well suited to interrogation of fluid flow in porous media. Because of the large scattering cross section of hydrogen it can be used to directly image water or hydrocarbons without an added contrast medium that might modify interfacial tension and fluid/fluid interactions. In order to understand the reaction of acidified fluids we used simultaneous neutron and X-ray tomography to study the uptake and reaction of water and an acidic fluid (pH 1 HCl) with two types of Indiana limestone, one with a permeability of 2-4 mD, and the other 70 mD. One set of experiments explored capillary uptake in a dry core. These documented rapid uptake and CO2 bubble formation at the inlet. A second set introduced at a constant forced flow rate of 10 ml/min. Both core types exhibited wormhole formation, but the low perm limestone wormhole consisted of one well-delineated channel with a few side "tributaries," whereas the high perm core exhibited a more diffuse array of channels. Post

  7. The French experience

    CERN Document Server

    Bougard, Marie-Thérèse

    2003-01-01

    Developed for beginners, The French Experience 1 course book is designed to accompany the French Experience 1 CDs (9780563472582) but can also be used on its own to develop your reading and writing skills. You’ll gain valuable insights into French culture too.

  8. A Metagenomic Survey of Limestone Hill in Taiwan

    Science.gov (United States)

    Hsu, Y. W.; Li, K. Y.; Chen, Y. W.; Huang, T. Y.; Chen, W. J.; Shih, Y. J.; Chen, J. S.; Fan, C. W.; Hsu, B. M.

    2016-12-01

    The limestone of Narro-Sky in Tainliao, Taiwan is of Pleistocene reef limestones interbedded in clastic layers that covered the Takangshan anticlines. Understanding how microbial relative abundance was changed in response to changes of environmental factors may contribute to better comprehension of roles that microorganisms play in altering the landscape structures. In this study, microorganisms growing on the wall of limestone, in the water dripping from the limestone wall and of soil underneath the wall were collected from different locations where the environmental factors such as daytime illumination, humidity, or pH are different. Next generation sequencing (NGS) was carried out to examine the compositions and richness of microbial community. The metagenomics were clustered into operational taxonomic units (OTUs) to analyze relative abundance, diversities and principal coordinates analysis (PCoA). Our results showed the soil sample has the highest alpha diversity while water sample has the lowest. Four major phyla, which are Proteobacteria, Acidobacteria, Actinobacteria, and Cyanobacteria, account for 80 % of total microbial biomass in all groups. Cyanobacteria were found most abundantly in limestone wall instead of water or soil of weathering limestone. The PCoA dimensional patterns of each phylum showed a trace of microbial community dynamic changes, which might be affected by environmental factors. This study provides the insights to understand how environmental factors worked together with microbial community to shape landscape structures.

  9. Converting SDAP into gypsum in a wet limestone scrubber

    Energy Technology Data Exchange (ETDEWEB)

    Fogh, F [Faelleskemikerne, Elsamprojekt A/S, Fredericia (Denmark)

    1996-12-01

    The ELSAM power pool has an installed electrical capacity of approx. 5 GW{sub e}, mainly firing import coal. The major base load units are equipped with desulphurization units and three different desulphurization technologies are used: the wet limestone gypsum process, the spray dry absorption process and a sulphuric acid process. Gypsum and sulphuric acid are commercialized, whereas it has been difficult to utilize the spray dry absorption product (SDAP). The main constituents of SDAP are calcium sulphide, calcium chloride, hydrated lime and impurities mainly originating from fly ash. Sulphide can be oxidized into sulphate in acidic solution - the reaction is utilized in the wet limestone gypsum process - and the possibility of using any spare capacity in the wet limestone gypsum units to oxidize the sulphide content of SDAP into sulphate and produce usable gypsum has been investigated in the laboratory and in a 400 MW{sub e} equivalent wet limestone unit. The limestone inhibition effect of the addition of SDAP is currently being studied in the laboratory in order to determine the effect of different SDAP types (plant/coal sources) on limestone reactivity before further long-term full-scale tests are performed and permanent use of the process planned. (EG)

  10. Influence of limestone on the hydration of Portland cements

    International Nuclear Information System (INIS)

    Lothenbach, Barbara; Le Saout, Gwenn; Gallucci, Emmanuel; Scrivener, Karen

    2008-01-01

    The influence of the presence of limestone on the hydration of Portland cement was investigated. Blending of Portland cement with limestone was found to influence the hydrate assemblage of the hydrated cement. Thermodynamic calculations as well as experimental observations indicated that in the presence of limestone, monocarbonate instead of monosulfate was stable. Thermodynamic modelling showed that the stabilisation of monocarbonate in the presence of limestone indirectly stabilised ettringite leading to a corresponding increase of the total volume of the hydrate phase and a decrease of porosity. The measured difference in porosity between the 'limestone-free' cement, which contained less than 0.3% CO 2 , and a cement containing 4% limestone, however, was much smaller than calculated. Coupling of thermodynamic modelling with a set of kinetic equations which described the dissolution of the clinker, predicted quantitatively the amount of hydrates. The quantities of ettringite, portlandite and amorphous phase as determined by TGA and XRD agreed well with the calculated amounts of these phases after different periods of time. The findings in this paper show that changes in the bulk composition of hydrating cements can be followed by coupled thermodynamic models. Comparison between experimental and modelled data helps to understand in more detail the dominating processes during cement hydration

  11. Modeling the influence of limestone addition on cement hydration

    Directory of Open Access Journals (Sweden)

    Ashraf Ragab Mohamed

    2015-03-01

    Full Text Available This paper addresses the influence of using Portland limestone cement “PLC” on cement hydration by characterization of its microstructure development. The European Standard EN 197-1:2011 and Egyptian specification ESS 4756-1/2009 permit the cement to contain up to 20% ground limestone. The computational tools assist in better understanding the influence of limestone additions on cement hydration and microstructure development to facilitate the acceptance of these more economical and ecological materials. μic model has been developed to enable the modeling of microstructural evolution of cementitious materials. In this research μic model is used to simulate both the influence of limestone as fine filler, providing additional surfaces for the nucleation and growth of hydration products. Limestone powder also reacts relatively slow with hydrating cement to form monocarboaluminate (AFmc phase, similar to the mono-sulfoaluminate (AFm phase formed in ordinary Portland cement. The model results reveal that limestone cement has accelerated cement hydration rate, previous experimental results and computer model “cemhyd3d” are used to validate this model.

  12. Thermal properties of the Cobourg Limestone

    Science.gov (United States)

    Pitts, Michelle

    The underground storage of used nuclear fuel in Deep Geologic Repositories (DGRs) has been a subject of research in Canada for decades. One important technical aspect of repository design is the accommodation of the mechanical impacts of thermal inputs (heating) from the fuel as it goes through the remainder of its life cycle. Placement room spacing, a major factor in project cost, will be determined by the ability of the host rock to dissipate heat. The thermal conductivity and linear thermal expansion will determine the evolution of the temperature and thermally-induced stress fields. Thermal processes must be well understood to design a successful DGR. This thesis examines the thermal properties of rocks, how they are influenced by factors such as temperature, pressure, mineralogy, porosity, and saturation; and common methods for calculating and/or measuring these properties. A brief overview of thermal and thermally-coupled processes in the context of DGRs demonstrates the degree to which they would impact design, construction, and operation of these critical structures. Several case histories of major in situ heating experiments are reviewed to determine how the lessons learned could be applied to a Canadian Underground Demonstration Facility (UDF). A mineralogy investigation using X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) examines samples of the Cobourg Limestone from the Bowmanville and Bruce sites, and demonstrates geographical variability within the Cobourg Formation. The thermal properties of samples from the Bowmanville site are determined. A divided bar apparatus was constructed and used to measure thermal conductivity. The temperature measurement component of the divided bar apparatus was used to measure linear thermal expansion. Finally, the past investigations into the thermal impact of a DGR are reviewed, and the implications of the laboratory testing results on similar analyses are discussed.

  13. French grammar and usage

    CERN Document Server

    Hawkins, Roger

    2015-01-01

    Long trusted as the most comprehensive, up-to-date and user-friendly grammar available, French Grammar and Usage is a complete guide to French as it is written and spoken today. It includes clear descriptions of all the main grammatical phenomena of French, and their use, illustrated by numerous examples taken from contemporary French, and distinguishes the most common forms of usage, both formal and informal.Key features include:Comprehensive content, covering all the major structures of contemporary French User-friendly organisation offering easy-to-find sections with cross-referencing and i

  14. French For Dummies

    CERN Document Server

    Erotopoulos; Williams, Michelle M; Wenzel, Dominique

    2011-01-01

    The fast, informal way to learn to speak French French is known as perhaps the most beautiful of all languages. Listen to someone speak French-sure, you don't have a clue what they're saying, but aren't you enraptured by the sound of it? French is a beautiful language but quite difficult to learn. Whether you need to learn the language for a French class, or you travel overseas for business or leisure, this revised edition of French for Dummies can help. Written in an easy-to-follow format, it gives you just what you need for basic communication in FrenchExpanded coverage of necessary grammar,

  15. The Time-Dependency of Deformation in Porous Carbonate Rocks

    Science.gov (United States)

    Kibikas, W. M.; Lisabeth, H. P.; Zhu, W.

    2016-12-01

    Porous carbonate rocks are natural reservoirs for freshwater and hydrocarbons. More recently, due to their potential for geothermal energy generation as well as carbon sequestration, there are renewed interests in better understanding of the deformation behavior of carbonate rocks. We conducted a series of deformation experiments to investigate the effects of strain rate and pore fluid chemistry on rock strength and transport properties of porous limestones. Indiana limestone samples with initial porosity of 16% are deformed at 25 °C under effective pressures of 10, 30, and 50 MPa. Under nominally dry conditions, the limestone samples are deformed under 3 different strain rates, 1.5 x 10-4 s-1, 1.5 x 10-5 s-1 and 1.5 x 10-6 s-1 respectively. The experimental results indicate that the mechanical behavior is both rate- and pressure-dependent. At low confining pressures, post-yielding deformation changes from predominantly strain softening to strain hardening as strain rate decreases. At high confining pressures, while all samples exhibit shear-enhanced compaction, decreasing strain rate leads to an increase in compaction. Slower strain rates enhance compaction at all confining pressure conditions. The rate-dependence of deformation behaviors of porous carbonate rocks at dry conditions indicates there is a strong visco-elastic coupling for the degradation of elastic modulus with increasing plastic deformation. In fluid saturated samples, inelastic strain of limestone is partitioned among low temperature plasticity, cataclasis and solution transport. Comparison of inelastic behaviors of samples deformed with distilled water and CO2-saturated aqueous solution as pore fluids provide experimental constraints on the relative activities of the various mechanisms. Detailed microstructural analysis is conducted to take into account the links between stress, microstructure and the inelastic behavior and failure mechanisms.

  16. Attrition of limestone by impact loading in fluidized beds

    Energy Technology Data Exchange (ETDEWEB)

    Fabrizio Scala; Fabio Montagnaro; Piero Salatino [Consiglio Nazionale delle Ricerche, Napoli (Italy). Istituto di Ricerche sulla Combustione

    2007-09-15

    The present study addresses limestone attrition and fragmentation associated with impact loading, a process which may occur extensively in various regions of fluidized bed (FB) combustors/gasifiers, primarily the jetting region of the bottom bed, the exit region of the riser, and the cyclone. An experimental protocol for the characterization of the propensity of limestone to undergo attrition/fragmentation by impact loading is reported. The application of the protocol is demonstrated with reference to an Italian limestone whose primary fragmentation and attrition by surface wear have already been characterized in previous studies. The experimental procedure is based on the characterization of the amount and particle size distribution of the debris generated upon the impact of samples of sorbent particles against a target. Experiments were carried out at a range of particle impact velocities between 10 and 45 m/s, consistent with jet velocities corresponding to typical pressure drops across FB gas distributors. The protocol has been applied to either raw or preprocessed limestone samples. In particular, the effect of calcination, sulfation, and calcination/recarbonation cycles on the impact damage suffered by sorbent particles has been assessed. The measurement of particle voidage and pore size distribution by mercury intrusion was also accomplished to correlate fragmentation with the structural properties of the sorbent samples. Fragmentation by impact loading of the limestone is significant. Lime displays the largest propensity to undergo impact damage, followed by the sorbent sulfated to exhaustion, the recarbonated sorbent, and the raw limestone. Fragmentation of the raw limestone and of the sulfated lime follows a pattern typical of the failure of brittle materials. The fragmentation behavior of lime and recarbonated lime better conforms to a disintegration failure mode, with an extensive generation of very fine fragments. 27 refs., 9 figs. 1 tab.

  17. Performance of japanese quails fed feeds containing different corn and limestone particle sizes

    Directory of Open Access Journals (Sweden)

    DA Berto

    2007-09-01

    Full Text Available This study aimed at evaluating performance and egg quality of Japanese quails fed feeds containing different corn and limestone particle sizes. A total number of 648 birds in the peak of production was distributed in a random complete block experimental design, using a 2x3 factorial arrangement (2 corn particle sizes and 3 limestone particle sizes. Birds were designated to one of two blocks, with six replicates of 18 birds each. Mean geometric diameter (MGD values used were 0.617mm and 0.723mm (corn fine and coarse particle sizes, respectively, and 0.361mm, 0.721mm, and 0.947mm (limestone fine, intermediate and coarse particle sizes, respectively. The following treatments were applied: T1: fine corn feed, with 100% fine limestone; T2: fine corn feed, with 50% fine limestone and 50% intermediate limestone; T3: fine corn feed, with 50% fine limestone and 50% coarse limestone; T4: coarse corn feed, with 100% fine limestone; T5: coarse corn feed, with 50% fine limestone and 50% intermediate limestone; T6: coarse corn feed, with 50% fine limestone and 50% coarse limestone. The experiment lasted 112 days, consisting of 4 cycles of 28 days. No significant interaction was observed among corn and limestone particle sizes for any of the analyzed parameters. There were no significant effects (p>0.05 of the tested corn particle sizes on quail performance or egg quality. There were significant (p<0.05 isolated effects of limestone particle size only on the percentage of cracked eggs, which was reduced when birds fed 50% coarse limestone (0.947mm and 50% fine limestone (0.361mm as compared to those fed 100% fine limestone. Therefore, the inclusion of 50% coarse limestone (0.947mm is recommended for quail egg production.

  18. CALCIUM OXIDE CHARACTERISTICS PREPARED FROM AMBUNTEN’S CALCINED LIMESTONE

    Directory of Open Access Journals (Sweden)

    Fatimatul Munawaroh

    2018-05-01

    Full Text Available Calcium oxide (CaO and calcium carbonate (CaCO3 are widely used in industry. CaO and CaCO3 can be synthesized or derived from limestone. The purpose of this study to determine the characteristics of CaO calcined limestone from Ambunten Sumenep. Lime in calcined at 850 ° C for 6 hours. Characterization of X-ray fluorescence (XRF was conducted to determine the chemical composition of limestone, X-ray diffraction test (XRD to find the lime crystalline phase and FTIR test to determine the absorption of wave number. XRF test results showed that the limestone chemical composition consisted of Ca of 95.37% as the dominant element, Mg of 4.1%, Fe 0.17% and Y by 0.39%. The XRD test results showed that the limestone crystal phase is ankerite (Ca [Fe, Mg] [CO3] 2 and after the calcined phase calcination is vaterite (Ca [OH] 2, calcite (CaO and calcite (CaCO3. While the FTIR test results show that the CaO spectra are seen at 3741.24, 1417.12 and 874.14 cm-1.

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

    Science.gov (United States)

    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.

  20. Characterization of Limestone as Raw Material to Hydrated Lime

    Science.gov (United States)

    Salem Hwidi, Rajeb; Nuraiti Tengku Izhar, Tengku; Saad, Farah Naemah Mohd

    2018-03-01

    In Malaysia, limestone is essentially important for the economic growth as raw materials in the industry sector. Nevertheless, a little attention was paid to the physical, chemical, mineralogical, and morphological properties of the limestone using X-ray fluorescence (X-RF), X-ray diffraction (X-RD), Fourier transform infrared spectroscopy (FTIR), and Scanning electron microscopy / energy dispersive x-ray spectroscopy (SEM-EDS) respectively. Raw materials (limestone rocks) were collected from Bukit Keteri area, Chuping, Kangar, Perlis, Malaysia. Lab crusher and lab sieved were utilized to prepare five different size of ground limestone at (75 µm, 150 µm, 225 µm, 300, and 425 µm) respectively. It is found that the main chemical composition of bulk limestone was Calcium oxide (CaO) at 97.58 wt.% and trace amount of MnO, Al2O3, and Fe2O3 at 0.02%, 0.35%, and 0.396% respectively. XRD diffractograms showed characteristic peaks of calcite and quartz. Furthermore, main FTIR absorption bands at 1,419, 874.08 and 712.20 cm-1 indicated the presence of calcite. The micrographs showed clearly the difference of samples particle size. Furthermore, EDS peaks of Ca, O, and C elements confirmed the presence of CaCO3 in the samples.

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

    Directory of Open Access Journals (Sweden)

    Macho Oliver

    2016-06-01

    Full Text Available 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.

  2. Limestone attrition under simulated oxyfiring Fluidized-Bed combustion conditions

    Energy Technology Data Exchange (ETDEWEB)

    Scala, F. [Istituto di Ricerche sulla Combustione - CNR, Napoli (Italy); Salatino, P. [Dipartimento di Ingegneria Chimica - Universita degli Studi di Napoli Federico II, Napoli (Italy)

    2009-03-15

    Limestone attrition by surface wear was studied during the flue gas desulfurization under simulated fluidized-bed (FB) oxyfiring conditions and hindered calcination. Bench-scale experimental tests were carried out using well-established techniques previously developed for the characterization of sulfation and attrition of sorbents in air-blown atmospheric FB combustors. The experimental limestone conversion and attrition results were compared with those previously obtained with the same limestone under simulated air-blown combustion conditions. The differences in the conversion and attrition extents and patterns associated with oxyfiring as compared to air-blown atmospheric combustion were highlighted and related to the different particle morphologies and thicknesses of the sulfate layer. It was noted that attrition could play an important role in practical circulating FB combustor operation, by effectively enhancing particle sulfation under both oxyfiring and air-blown combustion conditions. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  3. Characterization of limestone of region South and Southeast of Para

    International Nuclear Information System (INIS)

    Marinho, A.R.O.; Vieira, J.H.A.; Antunes Junior, L.V.; Medeiros, A.C.; Souza, G.P.

    2014-01-01

    Limestone is used in daily activities, and it is common the use of products containing calcium carbonate in various applications, from construction to food production, air purification to sewage treatment, the sugar refining materials for the toothpaste, the manufacture of glass and steel in the manufacture of paper, plastics, paints, ceramics and many others. The Limestone present in the region of south and southeast of Para is presented in deposits that have not been explored on a large scale, being justified a deepening in characteristics thereof. For the characterization of the material, gross samples were comminuted by crushing and ball mill, sieved and then separated into aliquots. In the end were used fluorescence analysis of X-ray, diffraction X-rays, determination of the moisture and loss on ignition of the material at 950 °C for one hour, obtaining results of a dolomitic limestone. (author)

  4. A comprehensive French grammar

    CERN Document Server

    Price, Glanville

    2013-01-01

    Characterized by clear and accessible explanations, numerous examples and sample sentences, a new section on register and tone, and useful appendices covering topics including age and time, A Comprehensive French Grammar, Sixth Edition is an indispensable tool for advanced students of French language and literature.A revised edition of this established, bestselling French grammarIncludes a new section on register and medium and offers expanded treatment of French punctuationFeatures numerous examples and sample sentences, and useful appendices covering topics including age, time, and dimension

  5. French essentials for dummies

    CERN Document Server

    Lawless, Laura K

    2011-01-01

    Just the core concepts you need to write and speak French correctly If you have some knowledge of French and want to polish your skills, French Essentials For Dummies focuses on just the core concepts you need to communicate effectively. From conjugating verbs to understanding tenses, this easy-to-follow guide lets you skip the suffering and score high at exam time. French 101 - get the lowdown on the basics, from expressing dates and times to identifying parts of speech Gender matters - see how a noun's gender determines the articles, adjectives, and pronouns y

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

    Science.gov (United States)

    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

  7. Neutralization of sulfuric acid solutions by calcite dissolution and the application to anoxic limestone drain design

    International Nuclear Information System (INIS)

    Huminicki, Danielle M.C.; Rimstidt, J. Donald

    2008-01-01

    Batch reactor (BR) experiments were conducted to measure the effect of hydrodynamics and gypsum coatings on calcite neutralization rates. A factorial array of BR experiments measured the H + concentration change by calcite dissolution over a pH range of 1.5-3.5 and Na 2 SO 4 concentrations of 0-1 M. The rate of H + concentration change with time was determined by numerical differentiation of H + concentration versus time. Regression modeling showed that for uncoated calcite, rates are only significantly affected by pH, r=-10 -2.32 a H + 0.76 . Whereas, for calcite coated with gypsum only time had a significant effect on calcite dissolution rates, r = -10 -1.96 t -0.53 . Because transport-limited dissolution rates for uncoated calcite are a function of the pH and Reynolds number, a model was developed to express the effects of these two variables on the rate of H + consumption for a solution with a Darcy velocity, q, through a porous medium with a particle radius, r p , such that r ' =1.08x10 -3 q 0.31 r p -0.69 m H + 0.87 . This equation was integrated via a numerical model to simulate the performance of an idealized anoxic limestone drain (ALD). This model predicts the pH and alkalinity change along the length of an ALD. The model shows that the efficiency of an ALD is greater when the Darcy velocity is low and the particle radius is small. In addition, the growth of gypsum coatings causes the rate of H + neutralization to decline as the square root of time as they form and block the H + transport to the calcite surface. Supersaturation with respect to gypsum, leading to coating formation, can be avoided by diluting the ALD feed solution or by replacing limestone with dolomite

  8. Oxic limestone drains for treatment of dilute, acidic mine drainage

    Science.gov (United States)

    Cravotta, Charles A.

    1998-01-01

    Limestone treatment systems can be effective for remediation of acidic mine drainage (AMD) that contains moderate concentrations of dissolved O2 , Fe3+ , or A13+ (1‐5 mg‐L‐1 ). Samples of water and limestone were collected periodically for 1 year at inflow, outflow, and intermediate points within underground, oxic limestone drains (OLDs) in Pennsylvania to evaluate the transport of dissolved metals and the effect of pH and Fe‐ and Al‐hydrolysis products on the rate of limestone dissolution. The influent was acidic and relatively dilute (pH 1 mg‐L‐1 ) but was near neutral (pH = 6.2‐7.0); Fe and Al decreased to less than 5% of influent concentrations. As pH increased near the inflow, hydrous Fe and Al oxides precipitated in the OLDs. The hydrous oxides, nominally Fe(OH)3 and AI(OH)3, were visible as loosely bound, orange‐yellow coatings on limestone near the inflow. As time elapsed, Fe(OH)3 and AI(OH)3 particles were transported downflow. During the first 6 months of the experiment, Mn 2+ was transported conservatively through the OLDs; however, during the second 6 months, concentrations of Mn in effluent decreased by about 50% relative to influent. The accumulation of hydrous oxides and elevated pH (>5) in the downflow part of the OLDs promoted sorption and coprecipitation of Mn as indicated by its enrichment relative to Fe in hydrous‐oxide particles and coatings on limestone. Despite thick (~1 mm) hydrous‐oxide coatings on limestone near the inflow, CaCO3 dissolution was more rapid near the inflow than at downflow points within the OLD where the limestone was not coated. The rate of limestone dissolution decreased with increased residence time, pH, and concentrations of Ca2+ and HCO3‐ and decreased PCO2. The following overall reaction shows alkalinity as an ultimate product of the iron hydrolysis reaction in an OLD:Fe2+ + 0.25 O2 +CaCO3 + 2.5 H2O --> Fe(OH)3 + 2 Ca2+ + 2 HCO3-where 2 moles of CaCO3 dissolve for each mole of Fe(OH)3 produced

  9. The new French Development aid towards French-speaking Africa

    OpenAIRE

    Konate, Sindou Michel

    2013-01-01

    This project is focused on French president François Hollande new policy initiation around French Development assistance issue, particularly to French speakingAfrica South of the Sahara. President Hollande wishes to distance himself from the practices of his predecessors on French Public Development Assistance toward its former African colonies This project is focused on French president François Hollande new policy initiation around French Development assistance issue, particularly to Fre...

  10. Use of the microcrystalline limestone as building material: the "GrisPulpis"case

    Directory of Open Access Journals (Sweden)

    García del Cura, M. A.

    2005-03-01

    Full Text Available Gris Pulpis is a Jurassic microcrystalline limestone found in the Maestrazgo Area of the Iberian Mountain Range (province of Castellón, Spain. This paper reports the results of a detailed study of the mineralogical, pelrographic and chromatic characteristics, as well as the durability, of this stone, classified as a commercial marble for its polish ability. The study determined the relationship between the structural characteristics of the stone, with a proliferation of stylolites and veins, and its physical properties. Its flexura I strength was found to be greater than would normally be expected in a structure with such a dense web of stylolites and veins. This is due to the structural and mineralogical properties of these stylolites, characterised by an extremely wavy design, scant mineral infillings and, occasionally, subsequent cementation. The characteristics of the porous media of homogeneous microcrystalline limestones such as Gris Pulpis largely explain the durability of this stone when exposed to freeze-thaw cycles and salt crystallisation. These arc the properties that make Gris Pulpis limestone, quarried in the Spanish Region of Valencia, a valuable building material for both architectural and civil engineering applications

    En este trabajo se analizan las propiedades físicas y la durabilidad de una caliza microcristalina.El Gris Pulpis es una caliza microcristalina del Jurásico de la Cordillera Ibérica (Maestrazgo, cuyas características mineralógicas, petrográficas, cromáticas y alterabilidad se determinan detalladamente. Su aptitud para el pulido hace que sea un mármol comercial. Se establece la influencia de sus características estructurales (estilolitos, vénulas... en sus propiedades físicas. Su resistencia a flexión supera los valores que cabría esperar en función de la estructura de esta roca que, a veces, presenta abundantes estilolitos y vénulas. Esto es debido a las características estructurales y

  11. Isotopic labeling for the understanding of the alteration of limestone used in built cultural heritage

    Science.gov (United States)

    Saheb, Mandana; Chabas, Anne; Mertz, Jean-Didier; Rozenbaum, Olivier; Verney-Carron, Aurélie

    2015-04-01

    This project belongs to a specific work aiming at developing isotopic tools to better understand the alteration of materials used in the built cultural heritage. It is focused on the study of the alteration of limestone used in the facades of historic buildings subject to atmospheric polluted environment. Actually in the elevated parts of the buildings, water as rainfall (runoff or wet deposition) or in vapor form (condensation or dry deposition) is the main agent of alteration. Thus, the rock/water interactions need to be well understood to propose adapted solution to better preserve the buildings. To identify the water transfer within the porous limestone and locate the reaction preferential sites, two isotopic tracers (D and 18O) are used to monitor the alteration solution (D) and locate the zones containing the secondary phases (18O). The Saint-Maximin limestone used in many monuments in the suburbs of Paris (France) as a building and restoration stone has been specifically studied. Pristine materials, stones from monuments (monuments in the Paris area) and samples altered in laboratory constitute the analytical corpus to compare different stages of alteration. In a first step the stones are characterized at different scales to identify the alteration pattern (SEM-EDS, Raman microspectrometry, XRD, rugosimetry) and study the water transfers (X-ray tomography, mercury porosimetry, imbibition kinetics). The samples are then altered in the laboratory by realistic and controlled wet or dry deposition using isotopically labeled solutions to locate the reaction zones by SIMS. The multiscale characterization of the alteration pattern has allowed proposing alteration mechanisms linked to the properties of the stones and their location inside the building. Moreover, the location of the reactive zones inside the materials determined by the isotopic experiments helps examining the role of the evolution of porosity and formation of alteration products within the material

  12. French PWR Safety Philosophy

    International Nuclear Information System (INIS)

    Conte, M. M.

    1986-01-01

    The first 900 MWe units, built under the American Westinghouse licence and with reference to the U. S. regulation, were followed by 28 standardized units, C P1 and C P2 series. Increasing knowledge and lessons learned from starting and operating experience of French nuclear power plants, completed by the experience learned from the operation of foreign reactors, has contributed to the improvement of French PWR design and safety philosophy. As early as 1976, this experience was taken into account by French Safety organisms to discuss, with Electricite de France, the safety options for the planned 1300 MWe units, P4 and P4 series. In 1983, the new reactor scheduled, Ni4 series 1400 MWe, is a totally French design which satisfies the French regulations and other French standards and codes. Based on a deterministic approach, the French safety analysis was progressively completed by a probabilistic approach each of them having possibilities and limits. Increasing knowledge and lessons learned from operating experience have contributed to the French safety philosophy improvement. The methodology now applied to safety evaluation develops a new facet of the in depth defense concept by taking highly unlikely events into consideration, by developing the search of safety consistency of the design, and by completing the deterministic approach by the probabilistic one

  13. Routledge French technical dictionary

    CERN Document Server

    1994-01-01

    The French-English volume of this highly acclaimed set consists of some 100,000 keywords in both French and English, drawn from the whole range of modern applied science and technical terminology. Covers over 70 subject areas, from engineering and chemistry to packaging, transportation, data processing and much more.

  14. French nuclear organization

    International Nuclear Information System (INIS)

    Naudet, G.

    1993-01-01

    The French nuclear organization is characterized by two main features: the small number of firms involved and the role of the Government. In this text we give the French organization for nuclear industry and the role of Government and public authorities. 7 figs

  15. Rheology, strain localization and stress history in the limestones of Bure (Meuse, France)

    International Nuclear Information System (INIS)

    Rolland, A.

    2013-01-01

    In order to demonstrate the feasibility of a radioactive waste repository (HLW) in clay-stone formation, the french national radioactive waste management agency (Andra) started in 2000 to build an underground research laboratory (URL) at Bure in the south of the Meuse district. The target horizon for the laboratory is a 135 m thick layer of argillaceous rock (Callovo-Oxfordian clay-stone) that lies between about 420 and 555 meters below the surface at the URL site. The argillite layer (COX) is surrounded by limestones from the Dogger and the Oxfordian ages (respectively 164,7 to 175,6 Ma and 161,2 to 164,7 Ma). Numerous stylolites were found in these limestones. The aim of this work is to study the rheology of these stylolites-rich horizons and the stylolites as stress gauges in the Dogger and Oxfordian formations. In this work, a wide range of samples with and without stylolites were sampled in the Dogger and Oxfordian formations. Petrophysical measurements and microstructural studies showed that all these limestones have a microporous structure. We showed that the stylolites induced significant variations in some physical properties and in the rock strength. Based on an analytical model, presented here in details, linking a characteristic length associated to the stylolites morphology and the stress associated to the development of that stylolites, a method for the morphology analysis of stylolites is developed, using a Fourier power spectrum technique, by taking into account all the difficulties linked to the use of cores from deep boreholes. We apply this method on stylolites at various depths, starting from the Oxfordian formation at a depth of 158 meters to the Dogger formation at a depth of 800 meters. No stylolites are found in the intermediate Callovo-Oxfordian clay-stone formation. We analyze 1D profiles taken on the outer part of the cores. In agreement with theoretical predictions, we always observe two regimes for small and large scales separated by a

  16. Essential French grammar

    CERN Document Server

    Thacker, Mike

    2014-01-01

    Essential French Grammar is an innovative reference grammar and workbook for intermediate and advanced undergraduate students of French (CEFR levels B2 to C1). Its clear explanations of grammar are supported by contemporary examples and lively cartoon drawings.  Each chapter contains: * real-life language examples in French, with English translations * a 'key points' box and tables that summarise grammar concepts * a variety of exercises to reinforce learning * a contemporary primary source or literary extract to illustrate grammar in context. To aid your understanding, this book also contains a glossary of grammatical terms in French and English, useful verb tables and a key to the exercises. Together, these features all help you to grasp complex points of grammar and develop your French language skills.

  17. Sodium sesquicarbonate (Akang) and limestone as catalysts for the ...

    African Journals Online (AJOL)

    Production of monoglycerides from palm and palm kernel oils were carried out using sodium sesquicarbonate (akang) and lime stone as catalysts.The results showed that the maximum monoglyceride formed is in the range of 49–57% of the fatty product for the limestone catalyst and 78 – 92% for the sodium ...

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

    Science.gov (United States)

    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.

  19. Effect of Limestone Powder on Microstructure of Ternary Cementitious System

    NARCIS (Netherlands)

    Zhang, Y.; Ye, G.

    2012-01-01

    The pressure to reach sustainability favours the development of ternary composite cement. The synergistic effect on mechanical behaviour at 28 days between limestone powder (LP) and pozzolanic additives, i.e. fly ash (FA) and blast furnace slag (BFS), has been documented. In order to better

  20. Kinetic Study of Calcination of Jakura Limestone Using Power Rate ...

    African Journals Online (AJOL)

    The calcination of Jakura limestone was also found to be first order reaction with respect to CaCO3 concentration having average regression coefficient of 0.99. The temperature dependent terms were found using Arrhenius law and it was observed that the reaction temperature has a direct effect on the rate of reaction.

  1. Limestone rocks analysis by X-ray fluorescence analysis

    International Nuclear Information System (INIS)

    Izquierdo M, G.; Ponce R, R.; Vazquez J, J.

    1996-01-01

    By request of a private company, employing basically X-ray fluorescence analysis (X RF), was established a fast and accurate method for the analysis of the major elements in limestone rocks. Additionally, for complementing analysis was determined by ion chromatography, the chlorides appearance and by atomic absorption of sodium. By gravimetry, was determined the losses by ignition and the alpha quartz. (Author)

  2. Hydrate Phase Assemblages in Calcium Sulfoaluminate - Metakaolin - Limestone Blends

    DEFF Research Database (Denmark)

    Pedersen, Malene Thostrup; Lothenbach, Barbara; Winnefeld, Frank

    2017-01-01

    The combination of a commercial calcium sulfoaluminate (CSA) cement with metakaolin (MK) and limestone (LS) as supplementary cementitious materials (SCMs) is investigated for a CSA replacement level of 20 wt%. In addition to a pure CSA cement, paste samples have been prepared for three blends wit...

  3. Flora of Chihuahuan desertscrub on limestone in northeastern Sonora, Mexico

    Science.gov (United States)

    Thomas R. Van Devender; Ana Lilia Reina-Guerrero; J. Jesus. Sanchez-Escalante

    2013-01-01

    Transects were done in desertscrub on limestone to characterize the flora of the westernmost Chihuahuan Desert. Most of the sites (15) were in the Municipios of Agua Prieta and Naco in northeastern Sonora, with single sites near Ascensión, northwestern Chihuahua and east of Douglas in southeastern Arizona. A total of 236 taxa were recorded on transects. Dicot perennial...

  4. Innovative Field Investigations in Limestone using a FACT-FLUTe

    DEFF Research Database (Denmark)

    Mosthaf, Klaus; Barrett Sørensen, Mie; Broholm, Mette Martina

    2015-01-01

    and the prevailing aqueous pore water concentrations for a range of hydraulic parameters and conditions typical for limestone aquifers. Results and outlook The sorption experiments showed very strong sorption with reasonably linear sorption isotherms over a very large concentration range for individual chlorinated...

  5. 0-6686 : improving DMS 9210 requirements for limestone rock asphalt : [project summary].

    Science.gov (United States)

    2013-08-01

    Limestone rock asphalt (LRA) mixtures have : been produced and placed for several decades : using specification requirements currently listed : under DMS 9210, Limestone Rock Asphalt (LRA). : Several Texas Department of Transportation : (TxDOT) distr...

  6. What French for Gabonese French Lexicography

    African Journals Online (AJOL)

    user

    administration, international relations, teaching, the media, trade, transport, tourism, .... The present study refutes such as reductive definition of what Gabonese .... language than French limits itself to public speeches and support to linguistics ...... sité Omar Bongo du Gabon: Série Lettres, Droit, Sciences et Médecine: 55-63.

  7. Assessment of Environmental Impacts of Limestone Quarrying Operations in Thailand

    Directory of Open Access Journals (Sweden)

    Kittipongvises Suthirat

    2017-11-01

    Full Text Available Environmental impacts of the mineral extraction have been a public concern. Presently, there is widespread global interest in the area of mining and its sustainability that focused on the need to shift mining industry to a more sustainable framework. The aim of this study was to systematically assess all possible environmental and climate change related impacts of the limestone quarrying operation in Thailand. By considering the life cycle assessment method, the production processes were divided into three phases: raw material extraction, transportation, and comminution. Both IMPACT 2002+ and the Greenhouse Gas Protocol methods were used. Results of IMPACT 2002+ analysis showed that per 1 ton crushed limestone rock production, the total depletion of resource and GHGs emissions were 79.6 MJ and 2.76 kg CO2 eq., respectively. Regarding to the four damage categories, ‘resources’ and ‘climate change’ categories were the two greatest environmental impacts of the limestone rock production. Diesel fuel and electricity consumption in the mining processes were the main causes of those impacts. For climate change, the unit of CO2 eq. was expressed to quantify the total GHGs emissions. Estimated result was about 3.13 kg CO2 eq. per ton limestone rock product. The results obtained by the Greenhouse Gas Protocol were also similar to IMPACT 2002+ method. Electrical energy consumption was considered as the main driver of GHGs, accounting for approximately 46.8 % of total fossil fuel CO2 emissions. A final point should be noted that data uncertainties in environmental assessment over the complete life cycle of limestone quarrying operation have to be carefully considered.

  8. Assessment of Environmental Impacts of Limestone Quarrying Operations in Thailand

    Science.gov (United States)

    Kittipongvises, Suthirat

    2017-11-01

    Environmental impacts of the mineral extraction have been a public concern. Presently, there is widespread global interest in the area of mining and its sustainability that focused on the need to shift mining industry to a more sustainable framework. The aim of this study was to systematically assess all possible environmental and climate change related impacts of the limestone quarrying operation in Thailand. By considering the life cycle assessment method, the production processes were divided into three phases: raw material extraction, transportation, and comminution. Both IMPACT 2002+ and the Greenhouse Gas Protocol methods were used. Results of IMPACT 2002+ analysis showed that per 1 ton crushed limestone rock production, the total depletion of resource and GHGs emissions were 79.6 MJ and 2.76 kg CO2 eq., respectively. Regarding to the four damage categories, `resources' and `climate change' categories were the two greatest environmental impacts of the limestone rock production. Diesel fuel and electricity consumption in the mining processes were the main causes of those impacts. For climate change, the unit of CO2 eq. was expressed to quantify the total GHGs emissions. Estimated result was about 3.13 kg CO2 eq. per ton limestone rock product. The results obtained by the Greenhouse Gas Protocol were also similar to IMPACT 2002+ method. Electrical energy consumption was considered as the main driver of GHGs, accounting for approximately 46.8 % of total fossil fuel CO2 emissions. A final point should be noted that data uncertainties in environmental assessment over the complete life cycle of limestone quarrying operation have to be carefully considered.

  9. Amine Functionalized Porous Network

    KAUST Repository

    Eddaoudi, Mohamed; Guillerm, Vincent; Weselinski, Lukasz Jan; Alkordi, Mohamed H.; Mohideen, Mohamed Infas Haja; Belmabkhout, Youssef

    2015-01-01

    Amine groups can be introduced in porous materials by a direct (one pot) or post-synthetic modification (PSM) process on aldehyde groups, and the resulting porous materials have increased gas affinity.

  10. Amine Functionalized Porous Network

    KAUST Repository

    Eddaoudi, Mohamed

    2015-05-28

    Amine groups can be introduced in porous materials by a direct (one pot) or post-synthetic modification (PSM) process on aldehyde groups, and the resulting porous materials have increased gas affinity.

  11. Additional Gigantoproductus species from the upper Visean-Namurian limestone of Kotaki, central Japan

    OpenAIRE

    Ibaraki, Yousuke; Tazawa, Jun-ichi; Nakamura, Yukio

    2010-01-01

    A large productid brachiopod species, Gigantoproductus aurita (Bolkhovitinova, 1938), is described from the Tsuchikurazawa Limestone (upper Visean-Namurian), a large limestone block within a Permian accretionary complex of Kotaki, Itoigawa City, Niigata Prefecture, central Japan. This is the fourth described Gigantoproductus species from the Tsuchikurazawa Limestone. The range of G. aurita may extend to late Visean on the basis of the previous fossil records of the limestone.

  12. French in Culinary World

    Directory of Open Access Journals (Sweden)

    Rila Hilma

    2011-10-01

    Full Text Available More than million foods have been made by people from all over the world in the latest years. People now try to create new cooks and make some creativity on it. Then, cooking which the field is culinary has become an art because it needs an artistic value to decorate the food, a good taste and proper technique in processing delicious food in order to make it a masterpiece. French culinary is as famous as the Eiffel tower in the heart of the country, Paris. Most of fine dining international restaurants apply the French menu and cooking. This article presents an overview about the French element in culinary world; starts from its history, kitchen organization, French menu spelling, and French cooking vocabulary. The discussion proceeds library research to compile the data. Later, the art of culinary is interesting to be learned because it contains the classical history of world civilization, in this case French civilization. The issue of cooking trend “nouvelle cuisine” was a masterpiece of one of the greatest chef in his time, Escoffier. French culinary is widely well-known in all over the world because of innovation, creativity, and proud. Those are spirits that we must learn.   

  13. What French for Gabonese French lexicography? | Assam | Lexikos

    African Journals Online (AJOL)

    This paper is a response to Mavoungou (2013a) who has pleaded for the production of a dictionary of Gabonese French as variant B of the French language. The paper intends to com-prehend the concept of "Gabonese French". It gives an outline of the situation of French within the language diversity of Gabon as a ...

  14. Use of French, Attitudes and Motivations of French Immersion Students.

    Science.gov (United States)

    Van der Keilen, Marguerite

    1995-01-01

    Compares the degree to which pupils in the French immersion and regular English school programs speak French and initiate contact with French people. Attitudes and motivations were significantly more positive, and social tolerance and self-rated competency in French were much higher in the immersion than in English program subjects. (29…

  15. French PWR safety philosophy

    International Nuclear Information System (INIS)

    Conte, M.

    1986-05-01

    Increasing knowledge and lessons learned from starting and operating experience of French nuclear power plants, completed by the experience learned from the operation of foreign reactors, has contributed to the improvement of French PWR design and safety philosophy. Based on a deterministic approach, the French safety analysis was progressively completed by a probabilistic approach, each of them having possibilities and limits. As a consequence of the global risk objective set in 1977 for nuclear reactors, safety analysis was extended to the evaluation of events more complex than the conventional ones, and later to the evaluation of the feasibility of the offsite emergency plans in case of severe accidents

  16. Flirting with French

    CERN Document Server

    Alexander, William

    2015-01-01

    William Alexander is not just a Francophile, he wants to be French. It's not enough to explore the country, to enjoy the food and revel in the ambience, he wants to feel French from the inside. Among the things that stand in his way is the fact that he can't actually speak the language. Setting out to conquer the language he loves (but which, amusingly, does not seem to love him back), Alexander devotes himself to learning French, going beyond grammar lessons and memory techniques to delve into the history of the language, the science of linguistics, and the art of translation. Along

  17. The French and energy

    International Nuclear Information System (INIS)

    Rouquette, Celine; Moreau, Sylvain; Bottin, Anne; Reperant, Patricia

    2012-08-01

    In 2012, as in 2011, the French are favourable to renewable energy. If they could, around 60% of them would opt for solar, fuelwood or heat pumps for heating. Wind power is also viewed favourably. Aware of environmental issues, the French are prepared to change their habits in the face of climate change, and two-thirds are even prepared to make sacrifices. One-third declares having already taken action or intending to do so to reduce their energy consumption. The cost of energy remains a central issue: faced with higher prices, half of French people would reduce their consumption. However, information on the subject of energy needs to be improved. (authors)

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

    Science.gov (United States)

    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.

  19. Tailored Porous Materials

    Energy Technology Data Exchange (ETDEWEB)

    BARTON,THOMAS J.; BULL,LUCY M.; KLEMPERER,WALTER G.; LOY,DOUGLAS A.; MCENANEY,BRIAN; MISONO,MAKOTO; MONSON,PETER A.; PEZ,GUIDO; SCHERER,GEORGE W.; VARTULI,JAMES C.; YAGHI,OMAR M.

    1999-11-09

    Tailoring of porous materials involves not only chemical synthetic techniques for tailoring microscopic properties such as pore size, pore shape, pore connectivity, and pore surface reactivity, but also materials processing techniques for tailoring the meso- and the macroscopic properties of bulk materials in the form of fibers, thin films and monoliths. These issues are addressed in the context of five specific classes of porous materials: oxide molecular sieves, porous coordination solids, porous carbons, sol-gel derived oxides, and porous heteropolyanion salts. Reviews of these specific areas are preceded by a presentation of background material and review of current theoretical approaches to adsorption phenomena. A concluding section outlines current research needs and opportunities.

  20. French plutonium management program

    International Nuclear Information System (INIS)

    Greneche, D.

    2002-01-01

    The French plutonium management program is summarized in this paper. The program considers nuclear generation as a major component of national electric power supply and includes the reprocessing of the spent fuel. (author)

  1. French Dictionaries. Series: Specialised Bibliographies.

    Science.gov (United States)

    Klaar, R. M.

    This is a list of French monolingual, French-English and English-French dictionaries available in December 1975. Dictionaries of etymology, phonetics, place names, proper names, and slang are included, as well as dictionaries for children and dictionaries of Belgian, Canadian, and Swiss French. Most other specialized dictionaries, encyclopedias,…

  2. Porous organic cages

    Science.gov (United States)

    Tozawa, Tomokazu; Jones, James T. A.; Swamy, Shashikala I.; Jiang, Shan; Adams, Dave J.; Shakespeare, Stephen; Clowes, Rob; Bradshaw, Darren; Hasell, Tom; Chong, Samantha Y.; Tang, Chiu; Thompson, Stephen; Parker, Julia; Trewin, Abbie; Bacsa, John; Slawin, Alexandra M. Z.; Steiner, Alexander; Cooper, Andrew I.

    2009-12-01

    Porous materials are important in a wide range of applications including molecular separations and catalysis. We demonstrate that covalently bonded organic cages can assemble into crystalline microporous materials. The porosity is prefabricated and intrinsic to the molecular cage structure, as opposed to being formed by non-covalent self-assembly of non-porous sub-units. The three-dimensional connectivity between the cage windows is controlled by varying the chemical functionality such that either non-porous or permanently porous assemblies can be produced. Surface areas and gas uptakes for the latter exceed comparable molecular solids. One of the cages can be converted by recrystallization to produce either porous or non-porous polymorphs with apparent Brunauer-Emmett-Teller surface areas of 550 and 23m2g-1, respectively. These results suggest design principles for responsive porous organic solids and for the modular construction of extended materials from prefabricated molecular pores.

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

    Science.gov (United States)

    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

  4. The French coal board and French society

    International Nuclear Information System (INIS)

    Ladoucette, Ph. de

    2004-01-01

    On 19 April 1946 the French national assembly passed a law for nationalizing the mineral fuel industry by a vote of 516 against only 31. 'Charbonnages de France' (CDF), the French coal board, was created and prospects were promising. During the reconstruction period (1945 - 1960), coal industry was a pillar of the French economy, the production of coal had been steadily growing to reach its top in 1958 with 59 Mt. The sixties showed the beginning of the decline of coal to the benefit of oil, natural gas and later nuclear energy. As early as 1967 CDF had a policy of promoting new industries in regions of mines in order to break down the mono-industry scheme and to favor staff conversion massively. In 1947 the number of people on the payroll of CDF was 360.000, this number was decreasing steadily to reach 23.000 in 1990. In 2004 the last deep mine to work in France was closed down. This article tells the story of coal mining in France by describing its ups and downs and by assessing its social impact

  5. 500 French verbs for dummies

    CERN Document Server

    Erotopoulos

    2013-01-01

    Vexed by French verbs? Fear no more! In 500 French Verbs For Dummies, beginning French language learners can find a quick reference for verbs in the basic present tenses. More advanced French speakers can utilize this book to learn more complex verb tenses and conjugations as well as advanced verbs with irregular endings. One page for each of the 500 most commonly used verbs in the French language -alphabetically arranged and numbered for easy referenceSpecial designation of the 50 most essential French verbsA summary of basic French grammar that incl

  6. English and French courses

    CERN Multimedia

    2014-01-01

    If one of your New Year’s resolutions is to learn a language, there is no excuse anymore!   You can attend one of our English or French courses and you can practise the language with a tandem partner! General and Professional French Courses The next session will take place from 27 January to 4 April 2014. These courses are open to all persons working on the CERN site, and to their spouses. Oral Expression This course is aimed at students with a good knowledge of French who want to enhance their speaking skills. Speaking activities will include discussions, meeting simulations, role-plays etc. The next session will take place from 27 January to 4 April 2014. Writing professional documents in French These courses are designed for non-French speakers with a very good standard of spoken French. The next session will take place from 27 January to 4 April 2014. Cours d’anglais général et professionnel La prochaine session se déroulera du 3 mars a...

  7. Geostatistical three-dimensional modeling of oolite shoals, St. Louis Limestone, southwest Kansas

    Science.gov (United States)

    Qi, L.; Carr, T.R.; Goldstein, R.H.

    2007-01-01

    In the Hugoton embayment of southwestern Kansas, reservoirs composed of relatively thin (Big Bow and Sand Arroyo Creek fields. Lithofacies in uncored wells were predicted from digital logs using a neural network. The tilting effect from the Laramide orogeny was removed to construct restored structural surfaces at the time of deposition. Well data and structural maps were integrated to build 3-D models of oolitic reservoirs using stochastic simulations with geometry data. Three-dimensional models provide insights into the distribution, the external and internal geometry of oolitic deposits, and the sedimentologic processes that generated reservoir intervals. The structural highs and general structural trend had a significant impact on the distribution and orientation of the oolitic complexes. The depositional pattern and connectivity analysis suggest an overall aggradation of shallow-marine deposits during pulses of relative sea level rise followed by deepening near the top of the St. Louis Limestone. Cemented oolitic deposits were modeled as barriers and baffles and tend to concentrate at the edge of oolitic complexes. Spatial distribution of porous oolitic deposits controls the internal geometry of rock properties. Integrated geostatistical modeling methods can be applicable to other complex carbonate or siliciclastic reservoirs in shallow-marine settings. Copyright ?? 2007. The American Association of Petroleum Geologists. All rights reserved.

  8. Attachment and Detachment Behavior of Human Adenovirus and Surrogates in Fine Granular Limestone Aquifer Material.

    Science.gov (United States)

    Stevenson, Margaret E; Sommer, Regina; Lindner, Gerhard; Farnleitner, Andreas H; Toze, Simon; Kirschner, Alexander K T; Blaschke, Alfred P; Sidhu, Jatinder P S

    2015-09-01

    The transport of human adenovirus, nanoparticles, and PRD1 and MS2 bacteriophages was tested in fine granular limestone aquifer material taken from a borehole at a managed aquifer recharge site in Adelaide, South Australia. Comparison of transport and removal of virus surrogates with the pathogenic virus is necessary to understand the differences between the virus and surrogate. Because experiments using pathogenic viruses cannot be done in the field, laboratory tests using flow-through soil columns were used. Results show that PRD1 is the most appropriate surrogate for adenovirus in an aquifer dominated by calcite material but not under high ionic strength or high pH conditions. It was also found that straining due to size and the charge of the colloid were not dominant removal mechanisms in this system. Implications of this study indicate that a certain surrogate may not represent a specific pathogen solely based on similar size, morphology, and/or surface charge. Moreover, if a particular surrogate is representative of a pathogen in one aquifer system, it may not be the most appropriate surrogate in another porous media system. This was apparent in the inferior performance of MS2 as a surrogate, which is commonly used in virus transport studies. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  9. Are the Vinjamur rocks carbonatites or meta-limestones?

    Energy Technology Data Exchange (ETDEWEB)

    Subbarao, K V; Bhaskar Rao, B [Indian Institute of Technology, Bombay (India). Dept. of Earth Sciences; Le Bas, M J [Univ. of Leicester, Leicester (United Kingdom). Dept. of Geology

    1995-08-01

    New whole-rock rare earth element (REE) data for the metacarbonate rocks inter bedded with schists at Vinjamur in the Nellore schist belt of Andhra Pradesh, show low total REE contents ({sigma}9-128 ppm) that are inconsistent with an igneous carbonatitic origin but which correspond more closely with a sedimentary limestone origin. The REE data of these rocks however, do not give absolute discrimination between marbles of meta-limestone and metacarbonatite origin. Micro-probe analytical data give better discrimination, and the chemical compositions of the calcite, micas, amphibole, plagioclase, apatite, monazite and staurolite in the Vinjamur marbles give strong and consistent evidence of a metamorphosed sedimentary rather than an igneous origin. (author). 35 refs., 7 figs., 9 tabs.

  10. The influence of combustion derived pollutants on limestone deterioration

    DEFF Research Database (Denmark)

    Johnson, JB; Montgomery, Melanie; Thompson, GE

    1996-01-01

    This study concerns quantification of the relative chemical degradation effects of dry deposition of combustion-derived atmospheric pollutants, HCl, SO2 and NO2, on Portland and Monks Park limestones, employing laboratory exposure chambers for periods of 30 days. Using presentation rates up to 40 x...... 10(-4) mu g cm(-2) s(-1), the pollutants were assessed individually and in various combinations, along with ozone as oxidant, at 84% RH with dry or water-wetted surfaces. The degradation was followed by analysis of exposed stone, for Cl-, SO42- and NO3-, and of run-off solution for Ca2+, in addition...... to the anions. From these data, the total calcium released from limestone to reaction ions and products and the percentages of each pollutant reacted (and so the deposition velocity (V-D)) in each exposure regime were calculated. HCl acted independently of the presence of other pollutants, showed 40 and 100...

  11. Induration and Biot’s Coefficient of Palaeogene Limestone

    DEFF Research Database (Denmark)

    Andreassen, Katrine Alling

    2017-01-01

    In engineering geology and classification of rock masses for civil engineering purposes, the degree of induration for a rock serves as a useful classification parameter. Induration is a measure of how well the grains of a sedimentary rock are cemented together - from loosely cemented/soft rock...... to very competent/slightly metamorphic rock. The Biot coefficient links to the degree of cementation in the capacity of how it relates the elastic deformations with the change in pore pressure. A hypothesis is that the degree of induration could be correlated to the magnitude of the Biot coefficient....... This is tested on 11 Copenhagen Limestone specimens of varying porosity and densities obtained from one borehole with a limestone interval of 30 m. Their induration varies from H2 to H5. Elastic wave propagation measurements are used to establish the Biot coefficient and determination of the mineralogy for H5...

  12. Are the Vinjamur rocks carbonatites or meta-limestones?

    International Nuclear Information System (INIS)

    Subbarao, K.V.; Bhaskar Rao, B.; Le Bas, M.J.

    1995-01-01

    New whole-rock rare earth element (REE) data for the metacarbonate rocks inter bedded with schists at Vinjamur in the Nellore schist belt of Andhra Pradesh, show low total REE contents (σ9-128 ppm) that are inconsistent with an igneous carbonatitic origin but which correspond more closely with a sedimentary limestone origin. The REE data of these rocks however, do not give absolute discrimination between marbles of meta-limestone and metacarbonatite origin. Micro-probe analytical data give better discrimination, and the chemical compositions of the calcite, micas, amphibole, plagioclase, apatite, monazite and staurolite in the Vinjamur marbles give strong and consistent evidence of a metamorphosed sedimentary rather than an igneous origin. (author). 35 refs., 7 figs., 9 tabs

  13. OPTIMALIZATION OF BLASTING IN »LAKOVIĆI« LIMESTONE QUARRY

    OpenAIRE

    Branko Božić; Karlo Braun

    1992-01-01

    The optimalization of exploitation in »Lakovići« limestone quarry is described. Based on determined discontinuities in the rock mass and their densities, the best possible working site have been located in order to obtain the best possible sizes of blasted rocks and work slope stability. Optimal lowest resistance line size for the quarry has been counted and proved experimentally. New blasting parameters have resulted in considerable saving of drilling and explosive (the paper is published in...

  14. Degradation behavior of limestone concrete under limited time sodium exposure

    International Nuclear Information System (INIS)

    Das, S.K.; Sharma, A.K.; Ramesh, S.S.; Parida, F.C.; Kasinathan, N.; Chellapandi, P.

    2009-01-01

    Adequate safety measures are taken during design, fabrication, construction and operation of liquid sodium cooled fast breeder reactor (FBR). However, possibility of sodium leak from secondary heat transport circuits of FBR has not been completely ruled out. In the areas housing sodium pipelines such as Steam Generator Building (SGB), spilled liquid sodium not only reacts with air causing fire but also interacts with structural concrete resulting in its degradation. The structural concrete can be protected from sodium attack using sodium resistant sacrificial concrete layer or steel/refractory liners. Moreover, design and construction of sloping floor with sodium collection pit helps in minimizing the mass of sodium accumulated on the floor and exposure period. Sacrificial concrete layer on the structural concrete should meet key factors like economy, castability, easy removal of affected concrete in the event of a sodium fire and disposability of debris apart from its good resistance against hot burning sodium. Present study is directed towards testing of limestone concrete blocks (made out of 13% ordinary portland cement, 8% water, 48% coarse limestone and 31 % fine limestone aggregates)

  15. Adsorption of anionic surfactants in limestone medium during oil recovery

    Energy Technology Data Exchange (ETDEWEB)

    Canbolat, Serhat; Bagci, Suat [Middle East Technical Univ., Dept. of Petroleum and Natural Gas Engineering, Ankara (Turkey)

    2004-07-15

    Foam-forming surfactant performance was evaluated by several experimental methods (interfacial tension, foam stability, corefloods) using commercial surfactants. There is considerable interest in the use of foam-forming surfactants for mobility control in water flood. To provide effective mobility control, the injected surfactant must propagate from the injection well toward the production well. One of the important parameters affecting propagation of foam-forming surfactant through the reservoir is the retention of surfactant due to its adsorption on reservoir rock. The determination of the adsorption of foam-forming surfactants in limestone reservoirs is important for the residual oil recovery efficiency. Adsorption measurements, recovery efficiencies, and surfactant and alkaline flooding experiments carried out with the representative of the selected surfactants alkaline solutions, linear alkyl benzene sulphonic acid (LABSA), sodium lauryl ether sulfate (SLES), and NaOH in a limestone medium. These surfactants were selected with respect to their foaming ability. Calibration curves formed by pH measurements were used to determine the correct adsorption amount of the used surfactants and recovery efficiency of these surfactants compared with base waterflooding. The results showed that LABSA adsorbed more than SLES in limestone reservoirs. The recovery efficiency of SLES was higher than the recovery efficiency of LABSA, and they decreased the recovery efficiency with respect to only the water injection case. (Author)

  16. Development of gypsum alteration on marble and limestone

    Science.gov (United States)

    McGee, E.S.

    1996-01-01

    Blackened alteration crusts of gypsum plus particulates that form on sheltered areas on marble and limestone buildings pose a challenge for rehabilitation and cleaning. Fresh marble and limestone samples exposed at monitored exposure sites present conditions of simple geometry and well-documented exposures but have short exposure histories (one to five years). The gypsum alteration crusts that develop on these samples provide insight into the early stages and rate of alteration crust formation. Alteration crusts from buildings give a longer, but less well known exposure history and present much more complex surfaces for gypsum accumulation. Integrated observations and measurements of alteration crusts from exposure samples and from buildings identify four factors that are important in the formation and development of alteration crusts on marble and limestone: (1) pollution levels, (2) exposure to rain or washing, (3) geometry of exposure of the stone surface, and (4) permeability of the stone. The combination of these factors contributes to both the distribution and the physical characteristics of the gypsum crusts which may affect cleaning decisions.

  17. Biogenic magnetite as a primary remanence carrier in limestone deposits

    Science.gov (United States)

    Chang, Shih-Bin R.; Kirschvink, Joseph L.; Stolz, John F.

    1987-06-01

    Studies on the microbial communities and magnetic phases of samples collected from carbonate oozes at Sugarloaf Key, FL, U.S.A. and calcareous laminated sediments from Laguna Figueroa, Baja California, Mexico have revealed the existence of magnetotactic bacteria and ultrafine-grained single domain magnetite in both environments. Magnetotactic bacteria were identified by light and electron microscopy. The single domain magnetite was detected by coercivity spectra analysis with a SQUID magnetometer and examined under the transmission electron microscope. The similarity, in terms of size and shape, between the single domain magnetite found in these sediments and the magnetite observed in the bacterial magnetosome from enriched cultures indicates the ultrafine-grained magnetite in these two marine environments was biologically formed. These results, combined with the common occurrences of ultrafine-grained magnetite in limestone deposits detected rock magnetically, suggest biogenic magnetite may be present and contribute to the magnetic remanence in these rocks. Several Cambrian limestone samples, separately collected from Siberia, China, and Kazakhstan, were examined for the presence of bacterial magnetite. Samples from the Lower Cambrian Sinskian Formation at Siberia Platform were found to contain both a large amount of apparently bacterial magnetite particles and a very stable primary magnetic component. Post-Cambrian diagenesis does not seem to affect the microgranulometry of these apparently bacterial magnetite crystals or the magnetic remanence carried by them. Assessing the potential role of biogenic magnetite as a primary remanence carrier in other Phanerozoic limestone deposits ought to be further pursued.

  18. The Biot coefficient for a low permeability heterogeneous limestone

    Science.gov (United States)

    Selvadurai, A. P. S.

    2018-04-01

    This paper presents the experimental and theoretical developments used to estimate the Biot coefficient for the heterogeneous Cobourg Limestone, which is characterized by its very low permeability. The coefficient forms an important component of the Biot poroelastic model that is used to examine coupled hydro-mechanical and thermo-hydro-mechanical processes in the fluid-saturated Cobourg Limestone. The constraints imposed by both the heterogeneous fabric and its extremely low intact permeability [K \\in (10^{-23},10^{-20}) m2 ] require the development of alternative approaches to estimate the Biot coefficient. Large specimen bench-scale triaxial tests (150 mm diameter and 300 mm long) that account for the scale of the heterogeneous fabric are complemented by results for the volume fraction-based mineralogical composition derived from XRD measurements. The compressibility of the solid phase is based on theoretical developments proposed in the mechanics of multi-phasic elastic materials. An appeal to the theory of multi-phasic elastic solids is the only feasible approach for examining the compressibility of the solid phase. The presence of a number of mineral species necessitates the use of the theories of Voigt, Reuss and Hill along with the theories proposed by Hashin and Shtrikman for developing bounds for the compressibility of the multi-phasic geologic material composing the skeletal fabric. The analytical estimates for the Biot coefficient for the Cobourg Limestone are compared with results for similar low permeability rocks reported in the literature.

  19. The French energy policy

    International Nuclear Information System (INIS)

    Maillard, D.; Baulinet, Ch.; Lajoinie, A.

    2001-01-01

    France has to face strong energy challenges: a heavy energy bill, increasing supplies risk, no decreasing CO 2 emissions, deregulation of energy markets, nuclear controversy etc.. In consequence, the French government has defined a voluntaristic energy policy with a better balance between the development of renewable energies and the mastery of energy and without renouncing the advantages of nuclear energy. In parallel, the electric power and natural gas industries have to cope with the deregulation of energy markets and the resulting competition. This issue of 'Energies et Matieres Premieres' newsletter comprises 3 articles. The first one gives a general presentation of the French energy policy ('mobilizing our margins of manoeuvre without renouncing our stakes'): challenges of the energy policy (greenhouse effect, security of supplies, long-term worldwide energy context, European integration, nuclear contestation), stakes for France (evolution of production structure, advantages of the French energy status), renewable energies and energy saving, long-term view of the nuclear industry, managing together the dynamism of competition and the advantages of public utilities. The second article entitled 'energy for everybody: a challenge for the 21. century' is a reprint of the introduction of the information report registered on January 31, 2001 by the commission of production and exchanges of the French national assembly. The third article is a reprint of the summary of conclusions and recommendations of the IEA about the French energy policy. (J.S.)

  20. Language Training - French Training

    CERN Multimedia

    HR Department

    2008-01-01

    General and Professional French Courses The next session will take place from 26 January to 3rd April 2009. These courses are open to all persons working on the CERN site, and to their spouses. For registration and further information on the courses, please consult our Web pages: http://cern.ch/Training or contact Mrs. Nathalie Dumeaux : Tel. 78144. Writing Professional Documents in French The next session will take place from 26 January to 3rd April 2009. This course is designed for people with a good level of spoken French. Duration: 30 hours Price: 660 CHF For further information and registration, please consult our Web pages: http://cern.ch/Training or contact Mrs. Nathalie Dumeaux : Tel. 78144. Nathalie Dumeaux Tel. 78144 mailto:nathalie.dumeaux@cern.ch

  1. Language Training - French Training

    CERN Multimedia

    HR Department

    2009-01-01

    General and Professional French Courses The next session will take place from 26 January to 3rd April 2009. These courses are open to all persons working on the CERN site, and to their spouses. For registration and further information on the courses, please consult our Web pages: http://cern.ch/Training or contact Mrs. Nathalie Dumeaux : Tel. 78144. Writing Professional Documents in French The next session will take place from 26 January to 3rd April 2009. This course is designed for people with a good level of spoken French. Duration: 30 hours Price: 660 CHF For further information and registration, please consult our Web pages: http://cern.ch/Training or contact Mrs. Nathalie Dumeaux : Tel. 78144. Nathalie Dumeaux Tel. 78144 mailto:nathalie.dumeaux@cern.ch

  2. French nuclear experience

    International Nuclear Information System (INIS)

    Reynolds, M.; Barre, B.

    1984-01-01

    The French nuclear attache at the French Embassy in Washington discusses his country's energy program and his role at the embassy as a representative of the French nuclear industry. He reviews the nuclear program's growth since it began in 1945, and the impetus of the OPEC oil embargo to accelerate the program since 1973. The success of France's nuclear program is due to a convergence of reasons that include incentive, the existence of a single utility that could design and manage a project of this magnitude, and the decision to focus on the pressurized water reactor (PWR) built by a single supplier and offering the benefits of standardization. Controlling the fuel cycle is the basic philosophy of both the PWR and the breeder program. Barre recommends policies of pre-approved sites, standardization, and licensing reform for the US

  3. French Antilles and Guiana.

    Science.gov (United States)

    1983-11-01

    This discussion of French Antilles and Guiana cover the following: the people, geography, history, government, political conditions, economy, and relations with the US. In 1983 the population totaled 303,000 with an annual growth rate of 0.09%. The infant mortality rate (1981) was 12.6/1000 and life expectancy 68 years. About 98% of the people of Martinique are of Afro European or Afro European Indian descent. The remainder are the old planter families and a sizable number of metropolitan French. Most of the work force are employed in agriculture or food processing and associated industries. Most permanent residents of Guadeloupe are of mixed Afro European descent. A few thousand Metropolitan French reside there. Most French Guianese live along the coast, about 1/2 of them in the capital. Martinique is the northernmost of the Windward Islands, which are part of the Lesser Antilles chain in the Caribbean Sea southeast of Puerto Rico. Guadeloupe comprises 2 of the Leeward Islands, which are also part of the Lesser Antilles chain. French Guiana is located on the northern coast of South America, a few degrees north of the Equator. Indians were the 1st known indigenous inhabitants of French Guiana and the French Antilles. Columbus sighted Guadeloupe in 1493, Martinique in 1493 or 1502, and the Guiana coast probably during his 3rd voyage in 1498. French Guiana, Guadeloupe, and Martinique, as overseas departments of France since 1946, are integral parts of the French Republic. Their relationship to Metropolitan France is somewhat similar to that of Alaska and Hawaii to the counterminous US. Each department has a general council composed of 1 representative elected by each canton. Guadeloupe and Martinique each elect 2 senators to the French Senate and 3 deputies to the National Assembly. French Guiana elects 1 senator and 1 deputy. In each of the 3 departments exist individuals and small political parties that advocate immediate independence, but their adherents form only

  4. The French energy programme

    International Nuclear Information System (INIS)

    Bohnen, U.

    1980-01-01

    The challenge of the oil crisis made French energy policy react chiefly by means of a programme for the rapid expansion of nuclear energy which has become unparalleled because of its systematic realization. The following article gives a survey of this programme and its political preconditions. The French energy programme deserves special attention as the utilization of nuclear energy in France including all related activities has reached a more advanced stage than in most other countries. The effects and requirements connected with such an extensive programme which can therefore be investigated with the help of the French example migth be of importance also for other countries in a similar way. (orig./UA) [de

  5. French grammar in context

    CERN Document Server

    Jubb, Margaret

    2013-01-01

    Instructors' edition without answer keysDiscount of 20% offered when 10 ebooks are sold- e.g. they will be sold for 263.60/ £151.90 instead of 329.50/£189.90French Grammar in Context presents a unique and exciting approach to learning grammar. Authentic texts from a rich variety of sources, literary and journalistic, are used as the starting point for the illustration and explanation of key areas of French grammar. Each point is consolidated with a wide range of written and spoken exercises. Grammar is presented not as an end in itself, but as a

  6. School of Economic French

    Directory of Open Access Journals (Sweden)

    I. S. Franceva

    2014-01-01

    Full Text Available Economic French at MGIMO-University is based on the teaching methods developed by talented Methodist practitioner assistant professor L.L. Potushanskoy. She and her colleagues G.M. Kotova, N. Kolesnikova, I.A. Yudina created well-known in our country methodical complex of three textbooks. This complex is built on clear guidelines to facilitate the natural development of language skills "from simple to complex" and represents the effective approach to language learning: Currently, the department is constantly expanding its boundaries of school teaching economic and business of the French language in accordance with the emerging new special courses on the economics faculties.

  7. Water flow in the Oxfordian and Dogger limestone around the Meuse/Haute-Marne underground research laboratory

    International Nuclear Information System (INIS)

    Linard, Y.; Vinsot, A.; Delay, J.; Scholz, E.; Lundy, M.; Garry, B.; La Vaissiere, R. de; Cruchaudet, M.; Dewonck, S.; Vigneron, G.; Vincent, B.; Wechner, S.

    2010-01-01

    water column. Dogger and Oxfordian formation waters were then collected. Sampling was performed by pumping, either at a low flow rate at the level of the water inflow with the 'Diapo' device, or at the end of a Long Term Pumping test (LTP). Several types of deep samplers were also used occasionally. In addition, waters of 7 porous levels in the Oxfordian limestone were sampled during the sinking of the URL main shaft. The geochemical characteristics of the sampled water were used in conjunction with the hydraulic measurements to propose a qualitative description of water flow in the Oxfordian and Dogger limestone on the studied area. Four main origins were identified for the water in the Oxfordian, whereas only two were identified in the Dogger limestone. The Oxfordian geological model reveals a clay-rich layer isolating two superposed aquifers in the North-East part of the studied area. The relationship between Mg 2+ and SO 4 2- concentrations in the water sampled in the upper Oxfordian aquifer and in the unique Oxfordian aquifer in the South-West of the studied area shows that the meteoritic water recharging the upper Oxfordian aquifer in the North-East was enriched in Mg 2+ , SO 4 2- and Na + . The later elements were come from the erosion of the Tithonian Purbeckian type facies. This enriched water mixed to the South-West with meteoritic water coming from the outcrops and/or infiltrating in the diffuse fracture area. Complementary analyses by several laboratories are in progress on the same samples. These further data will allow discussing the proposed water flow model

  8. Comparing Written Competency in Core French and French Immersion Graduates

    Science.gov (United States)

    Lappin-Fortin, Kerry

    2014-01-01

    Few studies have compared the written competency of French immersion students and their core French peers, and research on these learners at a postsecondary level is even scarcer. My corpus consists of writing samples from 255 students from both backgrounds beginning a university course in French language. The writing proficiency of core French…

  9. Kinetic Hydration Heat Modeling for High-Performance Concrete Containing Limestone Powder

    Directory of Open Access Journals (Sweden)

    Xiao-Yong Wang

    2017-01-01

    Full Text Available Limestone powder is increasingly used in producing high-performance concrete in the modern concrete industry. Limestone powder blended concrete has many advantages, such as increasing the early-age strength, reducing the setting time, improving the workability, and reducing the heat of hydration. This study presents a kinetic model for modeling the hydration heat of limestone blended concrete. First, an improved hydration model is proposed which considers the dilution effect and nucleation effect due to limestone powder addition. A degree of hydration is calculated using this improved hydration model. Second, hydration heat is calculated using the degree of hydration. The effects of water to binder ratio and limestone replacement ratio on hydration heat are clarified. Third, the temperature history and temperature distribution of hardening limestone blended concrete are calculated by combining hydration model with finite element method. The analysis results generally agree with experimental results of high-performance concrete with various mixing proportions.

  10. Simultaneous removal of several heavy metals from aqueous solution by natural limestones

    Directory of Open Access Journals (Sweden)

    Sdiri A.

    2014-07-01

    Full Text Available Four natural limestone samples, collected from the Campanian-Maastrichtian limestones, Tunisia, were used as adsorbents for the removal of toxic metals in aqueous systems. The results indicated that high removal efficiency could be achieved by the present natural limestones. Among the metal ions studied, Pb2+ was the most preferably removed cation because of its high affinity to calcite surface. In binary system, the presence of Cu2+ effectively depressed the sorption of Cd2+ and Zn2+. Similarly Cu2+ strongly competed with Pb2+ to limestone surface. In ternary system, the removal further decreased, but considerable amount of Pb2+ and Cu2+ still occurred regardless of the limestone sample. The same behavior was observed in quadruple system, where the selectivity sequence was Pb2+ > Cu2+ > Cd2+ > Zn2+. From these results, it was concluded that the studied limestones have the required technical specifications to be used for the removal of toxic metals from wastewaters.

  11. OPTIMALIZATION OF BLASTING IN »LAKOVIĆI« LIMESTONE QUARRY

    Directory of Open Access Journals (Sweden)

    Branko Božić

    1992-12-01

    Full Text Available The optimalization of exploitation in »Lakovići« limestone quarry is described. Based on determined discontinuities in the rock mass and their densities, the best possible working site have been located in order to obtain the best possible sizes of blasted rocks and work slope stability. Optimal lowest resistance line size for the quarry has been counted and proved experimentally. New blasting parameters have resulted in considerable saving of drilling and explosive (the paper is published in Croatian.

  12. Penetration of molten core materials into basaltic and limestone concrete

    International Nuclear Information System (INIS)

    Sutherland, H.J.

    1978-01-01

    In conjunction with the small-scale, melt-concrete interaction tests being conducted at Sandia Laboratories, an acoustic technique has been used to monitor the penetration of molten core materials into basaltic and limestone concrete. Real time plots of the position of the melt/concrete interface have been obtained, and they illustrate that the initial penetration rate of the melt may be of the order of 80 mm/min. Phenomena deduced by the technique include a non-wetted melt/concrete interface

  13. The French nuclear law

    International Nuclear Information System (INIS)

    Ito, Hiroshi

    2013-01-01

    The nuclear law had been out of the environmental law. The act on the transparency and the security of the nuclear matter was enacted in 2006 and set in the code of the environment in 2012. It means that the nuclear law is part of the environmental law and that it is advanced. I will report the French nuclear law. (author)

  14. The French Collection

    NARCIS (Netherlands)

    Vergeest, Aukje

    2000-01-01

    'What's happening right now in Paris?' This must have been the question that preoccupied many a 19th-century art dealer and artist. For the modern artist who wanted to make it in that period, Paris was no doubt the place to be. And it's from here that considerable amounts of French art managed to

  15. Complete French Teach Yourself

    CERN Document Server

    Graham, Gaelle

    2010-01-01

    The best-selling complete course for a fun and effective way to learn French. This ISBN is for the paperback book. The corresponding audio support (ISBN: 9781444100068) is also available. The book and audio support can also be purchased as a pack (ISBN: 9781444100051).

  16. French Theory's American Adventures

    Science.gov (United States)

    Cusset, Francois

    2008-01-01

    In this article, the author discusses how it is simply too late to be still speaking about French theory and its role in the intellectual life of the United States today. It seems to many observers that the gap between real-life politics and theory's guerrillas is much too wide already, after 30 years of academic fever, for the two worlds to even…

  17. I Can Speak French.

    Science.gov (United States)

    New York City Board of Education, Brooklyn, NY. Div. of Curriculum and Instruction.

    The guide presents content and techniques for teaching conversational French in the elementary grades. It contains an introductory section and 20 units for classroom instruction. The introduction includes notes on the overall objectives of the course, general guidelines on classroom procedure, and specific techniques for use of the materials…

  18. Hierarchical Porous Structures

    Energy Technology Data Exchange (ETDEWEB)

    Grote, Christopher John [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-06-07

    Materials Design is often at the forefront of technological innovation. While there has always been a push to generate increasingly low density materials, such as aero or hydrogels, more recently the idea of bicontinuous structures has gone more into play. This review will cover some of the methods and applications for generating both porous, and hierarchically porous structures.

  19. French Wines on the Decline?:

    DEFF Research Database (Denmark)

    Steiner, Bodo

    2004-01-01

    French wines, differentiated by geographic origin, served for many decades as a basis for the French success in the British wine market. However in the early 1990s, market share began to decline. This article explores the values that market participants placed on labelling information on French...

  20. Coralgal facies of the Upper Eocene-Lower Oligocene limestones in Letca-Rastoci area

    Directory of Open Access Journals (Sweden)

    Ioana Prica

    2001-09-01

    Full Text Available In this paper are described the coralgal facies identified in the Upper Eocene-Lower Oligocene limestone succession (Cozla Formation outcropping in two quarries at Letca and Rastoci (Sălaj district, Romania. In the studied profiles the coral and algae limestones are interlayered with bioclastic limestones with foraminifera. On the top of relatively deep water deposits, coral and algae crusts and dendritic corals coated by algae were deposited. The environment registered a gradual deepening, the deposits being completely immersed, while bioclastic limestones with foraminifera were recurrently formed. This cycle is repeated, the whole succession being caracterized by several such “parasequences”.

  1. Modelling of Limestone Dissolution in Wet FGD Systems: The Importance of an Accurate Particle Size Distribution

    DEFF Research Database (Denmark)

    Kiil, Søren; Johnsson, Jan Erik; Dam-Johansen, Kim

    1999-01-01

    Danish limestone types with very different particle size distributions (PSDs). All limestones were of a high purity. Model predictions were found to be qualitatively in good agreement with experimental data without any use of adjustable parameters. Deviations between measurements and simulations were...... attributed primarily to the PSD measurements of the limestone particles, which were used as model inputs. The PSDs, measured using a laser diffrac-tion-based Malvern analyser, were probably not representative of the limestone samples because agglomeration phenomena took place when the particles were...

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

    Science.gov (United States)

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

    2009-01-01

    Large amounts of limestone fines co-produced during the processing of crushed limestone may be useful in the sequestration of carbon dioxide (CO2). 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 CO2 is hydrated with water to produce carbonic acid. This reacts with and is neutralized by limestone fines, thus converting CO2 gas to dissolved calcium bicarbonate.

  3. Techniques for Source Zone and Plume Characterization of Tetrachloroethene in Fractured Limestone Aquifers

    DEFF Research Database (Denmark)

    Fjordbøge, Annika Sidelmann; Mosthaf, Klaus; Janniche, Gry S.

    Characterization of chlorinated solvents in fractured limestone aquifers is essential for proper development of site specific conceptual models and subsequent risk assessment and remediation. High resolution characterization is challenged by the difficulties involved in collection of intact core...... an improved conceptual understanding of contaminant transport. At both sites limestone cores were collected with significant core losses. The discrete quantification of chlorinated solvents in the retrieved limestone cores was compared to different FLUTe technologies at the DNAPL site and passive and active...... distribution compared to the data obtained by quantification of chlorinated solvents in the limestone cores....

  4. The effect of water on the sulphation of limestone

    Energy Technology Data Exchange (ETDEWEB)

    Chunbo Wang; Lufei Jia; Yewen Tan; E.J. Anthony [North China Electric Power University, Baoding City (China). School of Energy and Power Engineering

    2010-09-15

    A series of tests was conducted in a thermogravimetric analyzer (TGA) to study the sulphation behaviour of limestone in the presence of water over the temperature range of 800-850{sup o}C. Four different Canadian limestones, all with a particle size range of 75-425 {mu}m, were sulphated using a synthetic flue gas with a composition of 15% CO{sub 2}, 3% O{sub 2}, 0% or 10% H{sub 2}O, 1750 ppm SO{sub 2} and the balance N{sub 2}. Water was shown to have a significant promotional effect on sulphation, especially in the diffusion-controlled stage. However, the effect of water during the kinetic-controlled stage appeared to be much less pronounced. Based on these results, it is proposed that the presence of water leads to the transient formation of Ca(OH){sub 2} as an intermediate, which in turn reacts with SO{sub 2} at a faster rate than CaO does. Alternatively stated, it appears that H{sub 2}O acts as catalyst for the sulphation reaction of CaO. 30 refs., 8 figs., 3 tabs.

  5. Laser removal of water repellent treatments on limestone

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Heras, Miguel; Alvarez de Buergo, Monica; Rebollar, Esther; Oujja, Mohamed; Castillejo, Marta; Fort, Rafael

    2003-12-15

    Protective and water repellent treatments are applied on stone materials used on buildings or sculptures of artistic value to reduce water intrusion without limiting the natural permeability to water vapour of the material. The effect of the wavelength associated with the laser removal of two water repellent treatments applied on limestone, Paraloid B-72, a copolymer of methyl acrylate and ethyl methacrylate, and Tegosivin HL-100, a modified polysiloxane resin, was investigated by using the four harmonics of a Q-switched Nd:YAG laser (1064, 532, 355 and 266 nm). The modifications induced on the surface of limestone samples by laser irradiation were studied using colorimetry, roughness measurements and scanning electron microscopy (SEM). The removal of the treatments was found to be dependent on the laser irradiation conditions and on the characteristics of the coatings. The fundamental laser radiation was effective in removing both treatments, but thermal alteration processes were induced on the constituent calcite crystals. The best results were obtained by irradiation in the near UV at 355 nm.

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

    International Nuclear Information System (INIS)

    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

  7. Colmenar limestone as a resource for built heritage

    Science.gov (United States)

    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

  8. An improved method for permeability estimation of the bioclastic limestone reservoir based on NMR data.

    Science.gov (United States)

    Ge, Xinmin; Fan, Yiren; Liu, Jianyu; Zhang, Li; Han, Yujiao; Xing, Donghui

    2017-10-01

    Permeability is an important parameter in formation evaluation since it controls the fluid transportation of porous rocks. However, it is challengeable to compute the permeability of bioclastic limestone reservoirs by conventional methods linking petrophysical and geophysical data, due to the complex pore distributions. A new method is presented to estimate the permeability based on laboratory and downhole nuclear magnetic resonance (NMR) measurements. We divide the pore space into four intervals by the inflection points between the pore radius and the transversal relaxation time. Relationships between permeability and percentages of different pore intervals are investigated to investigate influential factors on the fluid transportation. Furthermore, an empirical model, which takes into account of the pore size distributions, is presented to compute the permeability. 212 core samples in our case show that the accuracy of permeability calculation is improved from 0.542 (SDR model), 0.507 (TIM model), 0.455 (conventional porosity-permeability regressions) to 0.803. To enhance the precision of downhole application of the new model, we developed a fluid correction algorithm to construct the water spectrum of in-situ NMR data, aiming to eliminate the influence of oil on the magnetization. The result reveals that permeability is positively correlated with percentages of mega-pores and macro-pores, but negatively correlated with the percentage of micro-pores. Poor correlation is observed between permeability and the percentage of meso-pores. NMR magnetizations and T 2 spectrums after the fluid correction agree well with laboratory results for samples saturated with water. Field application indicates that the improved method provides better performance than conventional models such as Schlumberger-Doll Research equation, Timur-Coates equation, and porosity-permeability regressions. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. An improved method for permeability estimation of the bioclastic limestone reservoir based on NMR data

    Science.gov (United States)

    Ge, Xinmin; Fan, Yiren; Liu, Jianyu; Zhang, Li; Han, Yujiao; Xing, Donghui

    2017-10-01

    Permeability is an important parameter in formation evaluation since it controls the fluid transportation of porous rocks. However, it is challengeable to compute the permeability of bioclastic limestone reservoirs by conventional methods linking petrophysical and geophysical data, due to the complex pore distributions. A new method is presented to estimate the permeability based on laboratory and downhole nuclear magnetic resonance (NMR) measurements. We divide the pore space into four intervals by the inflection points between the pore radius and the transversal relaxation time. Relationships between permeability and percentages of different pore intervals are investigated to investigate influential factors on the fluid transportation. Furthermore, an empirical model, which takes into account of the pore size distributions, is presented to compute the permeability. 212 core samples in our case show that the accuracy of permeability calculation is improved from 0.542 (SDR model), 0.507 (TIM model), 0.455 (conventional porosity-permeability regressions) to 0.803. To enhance the precision of downhole application of the new model, we developed a fluid correction algorithm to construct the water spectrum of in-situ NMR data, aiming to eliminate the influence of oil on the magnetization. The result reveals that permeability is positively correlated with percentages of mega-pores and macro-pores, but negatively correlated with the percentage of micro-pores. Poor correlation is observed between permeability and the percentage of meso-pores. NMR magnetizations and T2 spectrums after the fluid correction agree well with laboratory results for samples saturated with water. Field application indicates that the improved method provides better performance than conventional models such as Schlumberger-Doll Research equation, Timur-Coates equation, and porosity-permeability regressions.

  10. The french energy policy

    International Nuclear Information System (INIS)

    1991-01-01

    This book describes french energy policy from 1973 oil crisis till 1992. In a first part, energy consumption, domestic primary energy production, trend of independence energy ratio and costs of petroleum imports in France are presented. In a second part, long-term energy prospects and new axis of energy policy are given: trends of french energy needs, progressive substitution of fossil fuels by nuclear energy and hydroelectric power, energy policy in Common Market and cooperation with eastern Europe. In a third part, energy demand and supply are studied: energy conservation policy in housing, transport and industrial sector is developed. Power generation policy is focused on two main stakes: the choice of investments and nuclear power plants programming, the quality of electric power and the development of efficient uses and exports. A diversification between coal petroleum and natural gas is led. After the fall of petroleum prices in 1986, renewable energies have lost their competitiveness, fire wood occupies a significant place

  11. French nuclear energy policy

    International Nuclear Information System (INIS)

    Ferrari, A.; Bertel, E.

    1980-11-01

    The French energy policy is supported by a lucid view of the situation of our country and the constraints linked to the international context. This statement implies, the definition of a French policy or energy production essentially based on national resources, uranium, and especially for long term, technical know how which allows using plutonium in breeder reactors. This policy implies an effort in R and D, and industrial development of nuclear field, both in reactor construction and at all levels of fuel cycle. This coherent scientific and financial effort has been pursued since the beginning of years 60, and has placed France among the first nuclear countries in the world. Now this effort enables the mastership of a strong nuclear industry capable to assure the energy future of the country [fr

  12. Fabricating porous silicon carbide

    Science.gov (United States)

    Shor, Joseph S. (Inventor); Kurtz, Anthony D. (Inventor)

    1994-01-01

    The formation of porous SiC occurs under electrochemical anodization. A sample of SiC is contacted electrically with nickel and placed into an electrochemical cell which cell includes a counter electrode and a reference electrode. The sample is encapsulated so that only a bare semiconductor surface is exposed. The electrochemical cell is filled with an HF electrolyte which dissolves the SiC electrochemically. A potential is applied to the semiconductor and UV light illuminates the surface of the semiconductor. By controlling the light intensity, the potential and the doping level, a porous layer is formed in the semiconductor and thus one produces porous SiC.

  13. French courses for Beginners

    CERN Multimedia

    HR Department

    2009-01-01

    French courses for beginners (level 0) will take place from 13 July to 27 August 2009. •\tTimetable: Mondays, Tuesdays, Wednesdays, Thursdays (11:00 to 13:00 or 13:30 to 15:30) •\tDuration: 56 hours (8 hours a week) •\tPrice: 728 CHF For registration and further information on the courses, please consult our Web pages: http://cern.ch/Training or contact Mrs. Dumeaux, tel. 78144.

  14. French courses for Beginners

    CERN Multimedia

    HR Department

    2009-01-01

    French courses for beginners (level 0) will take place from 13 July to 27 August 2009. •\tTimetable: Mondays, Tuesdays, Wednesdays, Thursdays (11:00 to 13:00 or 13:30 to 15:30) •\tDuration: 56 hours (8 hours a week) •\tPrice: 728 CHF For registration and further information on the courses, please consult our Web pages: http://cern.ch/Training or contact Mrs. Dumeaux: Tel. 78144.

  15. French courses for Beginners

    CERN Multimedia

    HR Department

    2009-01-01

    French courses for beginners (level 0) will take place from 13 July to 27 August 2009. •\tTimetable: Mondays, Tuesdays, Wednesdays, Thursdays (11.00 to 13.00 or 13.30 to 15.30) •\tDuration: 56 hours (8 hours a week) •\tPrice: 728 CHF For registration and further information on the courses, please consult our Web pages: http://cern.ch/Training or contact Mrs. Dumeaux : Tel. 78144.

  16. French experience with electropolishing

    International Nuclear Information System (INIS)

    Saurin, P.; Weber, C.; Brissaud, A.; Gouillardou, G.

    1989-01-01

    Among the various techniques to minimize corrosion products deposition on out of core areas, surface polishing has been researched. The attention of French partners was drawn to this technique and a test was conducted at Chinon B1 NPP in 1984 using six manway covers with various surface finishing (mechanical polishing, electropolishing, mechanical plus electropolishing/on reference). On the basis of the good results obtained and with beneficial cost considerations the electropolishing of SGCH has been decided for new EDF reactors. Once the decision was made feasibility and qualifications programs were developed. Taking into account the promising results obtained, EDF asked FRAMATOME to perform the first electropolishing operation on one steam generator channel head at Nogent 1 in 1987. Since 1988 the French experience consists of the electropolishing of 4SG at Nogent 2, 4SG at Cattenom 3, 4SG at Penly 1 and 4SG at Golfech 1 (NPP), and is perfectly satisfactory. The industrial operation provides excellent polishing and does not create undesired effects. The French partners are now thinking of a new device which could be realised at FRAMATOME especially for steam generator replacement. (author)

  17. Language Training: French

    CERN Multimedia

    Françoise Benz

    2004-01-01

    If you wish to participate in one of the following courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at: http://www.cern.ch/Training/ or fill in an 'application for training' form available from your Divisional Secretariat or from your DTO (Divisional Training Officer). Applications will be accepted in the order of their receipt.General and Professional French Courses The next session will take place from 26 April to 02 July 2004. These courses are open to all persons working on the Cern site, and to their spouses. For registration and further information on the courses, please consult our Web pages: http://cern.ch/Training or contact Mrs. Benz: Tel. 73127. Writing Professional Documents in French The next session will take place from 26 April to 02 July 2004. This course is designed for people with a good level of spoken French. Duration: 30 hours Price: 660 CHF (for 8 students) For further information and registra...

  18. Science Diplomacy: French Experience

    Directory of Open Access Journals (Sweden)

    Alexei V. Shestopal

    2016-01-01

    Full Text Available The article deals with the formulation in France in the early twenty-first century of a new kind of diplomacy - science diplomacy. It studies the reasons for this process and its problems. On the one hand, the French foreign policy doctrine presupposes an ability to exercise certain influence on its international partners. However, its goals in this area are reduced to mere survival under conditions dictated by other countries. Modern trends in the world of science, which lead to integration, force to reconsider the attitude towards staff training, to research itself, and to its place and role in politics and diplomacy. However, an achievement of the French political class is an understanding of the main aspects of what is happening. This understanding leads to the search for ways to adapt to the new situation. At the same time, diplomats can operate only with those resources that are available to them. Competition with the US, China and other countries for scientific personnel and achievements cannot be won by diplomatic means alone, without backing by appropriate legal, economic and other efforts which provide favorable conditions for winning the competition. The main causes of France's unfavorable position in the struggle for an independent science are economic and political. It is they that lead to conditions, which prohibit French scientists to live up to their potential at home.

  19. REPLACEMENT OF FRENCH CARDS

    CERN Multimedia

    Human Resources Division

    2001-01-01

    The French Ministry of Foreign Affairs has informed the Organization that it is shortly to replace all diplomatic cards, special cards and employment permits ('attestations de fonctions') now held by members of the personnel and their families. Between 2 July and 31 December 2001, these cards are to be replaced by secure, computerized equivalents. A 'personnel office' stamped photocopy of the old cards may continue to be used until 31 December 2001. For the purposes of the handover, members of the personnel must go personally to the cards office (33/1-015), between 8:30 and 12:30, in order to fill a 'fiche individuelle' form (in black ink only), which has to be personally signed by themselves and another separately signed by members of their family, taking the following documents for themselves and members of their families already in possession of a French card : A recent identity photograph in 4.5 cm x 3.5 cm format (signed on the back) The French card in their possession an A4 photocopy of the same Fre...

  20. Language Training - French Training

    CERN Document Server

    2007-01-01

    General and Professional French Courses The next session will take place from 29 January to 30 March 2007. These courses are open to all persons working on the CERN site, and to their spouses. For registration and further information on the courses, please consult our Web pages: http://cern.ch/Training or contact Mrs. Benz : Tel. 73127. Writing Professional Documents in French The next session will take place from 29 January to 30 March 2007. This course is designed for people with a good level of spoken French. Duration: 30 hours Price: 660 CHF (for 8 students) For further information and registration, please consult our Web pages:   http://cern.ch/Training or contact Mrs. Benz : Tel. 73127. Writing Professional Documents in English The next session will take place from January to June 2007 (break at Easter). This course is designed for people with a good level of spoken English. Duration: 30 hours Price: 660 CHF (for 8 students) Timetable will be fixed after discussion with the students. For registratio...

  1. Compressive strength evolution of thermally-stressed Saint Maximin limestone.

    Science.gov (United States)

    Farquharson, J.; Griffiths, L.; Baud, P.; Wadsworth, F. B.; Heap, M. J.

    2017-12-01

    The Saint Maximin quarry (Oise, France) opened in the early 1600s, and its limestone has been used extensively as masonry stone, particularly during the classical era of Parisian architecture from the 17th century onwards. Its widespread use has been due to a combination of its regional availability, its high workability, and its aesthetic appeal. Notable buildings completed using this material include sections of the Place de la Concorde and the Louvre in Paris. More recently, however, it has seen increasing use in the construction of large private residences throughout the United States as well as extensions to private institutions such as Stanford University. For any large building, fire hazard can be a substantial concern, especially in tectonically active areas where catastrophic fires may arise following large-magnitude earthquakes. Typically, house fires burn at temperatures of around 600 °C ( 1000 F). Given the ubiquity of this geomaterial as a building stone, it is important to ascertain the influence of heating on the strength of Saint Maximin limestone (SML), and in turn the structural stability of the buildings it is used in. We performed a series of compressive tests and permeability measurements on samples of SML to determine its strength evolution in response to heating to incrementally higher temperatures. We observe that the uniaxial compressive strength of SML decreases from >12 MPa at room temperature to 400 °C). We anticipate that this substantial weakening is in part a result of thermal microcracking, whereby changes in temperature induce thermal stresses due to a mismatch in thermal expansion between the constituent grains. This mechanism is compounded by the volumetric increase of quartz through its alpha - beta transition at 573 °C, and by the thermal decomposition of calcite. To track the formation of thermal microcracks, we monitor acoustic emissions, a common proxy for microcracking, during the heating of an SML sample. The

  2. Oriented nucleation and growth of anhydrite during direct sulfation of limestone

    DEFF Research Database (Denmark)

    Hu, Guilin; Dam-Johansen, Kim; Wedel, Stig

    2008-01-01

    The direct sulfation of limestone (Iceland Spar) was studied at 973 K in a fixed-bed reactor. Scanning electron microscopy examinations of the sulfated limestone particles show that the sulfation process involves oriented nucleation and growth of the solid product, anhydrite. The reason...

  3. Model for the sulfidation of calcined limestone and its use in reactor models.

    NARCIS (Netherlands)

    Heesink, Albertus B.M.; Brilman, Derk Willem Frederik; van Swaaij, Willibrordus Petrus Maria

    1998-01-01

    A mathematical model describing the sulfidation of a single calcined limestone particle was developed and experimentally verified. This model, which includes no fitting parameters, assumes a calcined limestone particle to consist of spherical grains of various sizes that react with H2S according to

  4. Development of engineered cementitious composites with limestone powder and blast furnace slag

    NARCIS (Netherlands)

    Zhou, J.; Qian, S.; Sierra Beltran, M.G.; Ye, G.; Van Breugel, K.; Li, V.C.

    2009-01-01

    Nowadays limestone powder and blast furnace slag (BFS) are widely used in concrete as blended materials in cement. The replacement of Portland cement by limestone powder and BFS can lower the cost and enhance the greenness of concrete, since the production of these two materials needs less energy

  5. LATEST TOURNAISIAN (EARLY CARBONIFEROUS CONODONTS FROM THE TABAI LIMESTONE, TIRAH, NORTHWESTERN PAKISTAN

    Directory of Open Access Journals (Sweden)

    FAZL-I-RABBI KHAN

    2004-11-01

    Full Text Available A new stratigraphic unit, the Tabai Limestone of the poorly known Tirah area of northwest Pakistan, is one of several Early Carboniferous carbonate units distributed along the North Gondwana margin, some connected with transgressive interludes. The Tabai Limestone has produced latest Tournaisian (Early Carboniferous conodonts indicative of the middle of the anchoralis-latus Zone.

  6. High Resolution Hydraulic Profiling and Groundwater Sampling using FLUTe™ System in a Fractured Limestone Setting

    DEFF Research Database (Denmark)

    Janniche, Gry Sander; Christensen, Anders G.; Grosen, Bernt

    challeng-ing in deposit types as fractured limestone. The activities of a bulk distribution facility for perchloroe-thene (PCE) and trichloroethene (TCE) at the Naverland site near Copenhagen, Denmark, has resulted in PCE and TCE DNAPL impacts to a fractured clay till and an underlying fractured limestone...

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

    Science.gov (United States)

    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...

  8. Holocene limestones of part of the western continental shelf of India

    Digital Repository Service at National Institute of Oceanography (India)

    Nair, R.R.; Hashimi, N.H.; Guptha, M.V.S.

    , while those on te upper continental slope (130-180 m) are algal bryozoan limestones. The limestones have a radiocarbon age ranging between 9,000 and 11,000 years. Depositional environmental on the continental shelf during the Holocene appears...

  9. Evaluation of the Efficiency of Limestone Powder in Concrete and the Effects on the Environment

    Directory of Open Access Journals (Sweden)

    Yoo-Jae Kim

    2018-02-01

    Full Text Available The major environmental impact of concrete comes from the CO2 emissions, produced during the cement manufacturing process. The main goal of this research project is to evaluate the efficiency of limestone powder as a partial cement replacement, in order to reduce energy consumption and CO2 emissions. This study utilizes limestone powders, with different particle sizes, to replace a portion of Portland cement using various ratios. Due to the dilution effect when partially replacing cement, there is a reduction in the concrete’s physical properties. To assess the dilution effect, a modification to Féret’s equation is used to calculate an efficiency factor for the limestone powder when compared to cement. To measure the environmental impact, a life cycle assessment is conducted on concrete made with limestone powder combined with cement. This allows for an evaluation of the various cement/limestone powder ratios that will maximize the environmental benefit, with minimal reduction in concrete strength. Additional microstructural analysis using petrographic examination was completed to provide a visual understanding of the distribution of the limestone particles within the cement paste. The results indicate that the efficiency of limestone powder in partially replacing cement can be achieved by particle packing and particle distribution in the concrete and the benefits of emission reductions exceed the loss in compressive strength when higher levels of limestone powder is used to replace cement.

  10. Semiplanus (Productida, Brachiopoda) from the Carboniferous limestone of Kotaki, Niigata Prefecture, central Japan

    OpenAIRE

    Ibaraki, Yousuke; Sato, Kiichi

    2013-01-01

    An Early Carboniferous large–sized productid brachiopod species, Semiplanus semiplanus (Schwetzow, 1922), is described from the Tsuchikurazawa Limestone (upper Visean–Serpukhovian), a limestone block within a Permian accretionary complex, distributed in the Kotaki area, Itoigawa City, Niigata Prefecture, central Japan. This is the first record of Semipanus species from Japan.

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

    Science.gov (United States)

    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...

  12. Effect of limestone particle size and calcium to non-phytate phosphorus ratio on true ileal calcium digestibility of limestone for broiler chickens.

    Science.gov (United States)

    Anwar, M N; Ravindran, V; Morel, P C H; Ravindran, G; Cowieson, A J

    2016-10-01

    The purpose of this study was to determine the effect of limestone particle size and calcium (Ca) to non-phytate phosphorus (P) ratio on the true ileal Ca digestibility of limestone for broiler chickens. A limestone sample was passed through a set of sieves and separated into fine (digestibility of Ca was calculated using the indicator method and corrected for basal endogenous losses to determine the true Ca digestibility. The basal ileal endogenous Ca losses were determined to be 127 mg/kg of dry matter intake. Increasing Ca:non-phytate P ratios reduced the true Ca digestibility of limestone. The true Ca digestibility coefficients of limestone with Ca:non-phytate P ratios of 1.5, 2.0 and 2.5 were 0.65, 0.57 and 0.49, respectively. Particle size of limestone had a marked effect on the Ca digestibility, with the digestibility being higher in coarse particles (0.71 vs. 0.43).

  13. Stochastic porous media equations

    CERN Document Server

    Barbu, Viorel; Röckner, Michael

    2016-01-01

    Focusing on stochastic porous media equations, this book places an emphasis on existence theorems, asymptotic behavior and ergodic properties of the associated transition semigroup. Stochastic perturbations of the porous media equation have reviously been considered by physicists, but rigorous mathematical existence results have only recently been found. The porous media equation models a number of different physical phenomena, including the flow of an ideal gas and the diffusion of a compressible fluid through porous media, and also thermal propagation in plasma and plasma radiation. Another important application is to a model of the standard self-organized criticality process, called the "sand-pile model" or the "Bak-Tang-Wiesenfeld model". The book will be of interest to PhD students and researchers in mathematics, physics and biology.

  14. Limestone fragmentation and attrition during fluidized bed oxyfiring

    Energy Technology Data Exchange (ETDEWEB)

    Fabrizio Scala; Piero Salatino [Istituto di Ricerche sulla Combustione - CNR, Napoli (Italy)

    2010-04-15

    Attrition/fragmentation of limestone under simulated fluidized bed oxyfiring conditions was investigated by means of an experimental protocol that had been previously developed for characterization of attrition/fragmentation of sorbents in air-blown atmospheric fluidized bed combustors. The protocol was based on the use of different and mutually complementary techniques. The extent and pattern of attrition by surface wear in the dense phase of a fluidized bed were assessed in experiments carried out with a bench scale fluidized bed combustor under simulated oxyfiring conditions. Sorbent samples generated during simulated oxyfiring tests were further characterized from the standpoint of fragmentation upon high velocity impact by means of a purposely designed particle impactor. Results showed that under calcination-hindered conditions attrition and fragmentation patterns are much different from those occurring under air-blown atmospheric combustion conditions. Noteworthy, attrition/fragmentation enhanced particle sulfation by continuously regenerating the exposed particle surface. 13 refs., 8 figs.

  15. Sierra Elvira limestone: petrophysical characteristics of an Andalusian heritage stone

    Directory of Open Access Journals (Sweden)

    Valverde, I.

    2008-06-01

    Full Text Available “Sierra Elvira stone” is one of the ornamental building stones most widely used in the historical monuments of eastern Andalusia. A Liassic age limestone, it appears in the central section of the Baetic Mountains and more specifically in the Middle Subbaetic domain. While the most common variety is a crinoid limestone, a micritic limestone of the same age has also been quarried, albeit in much smaller quantities. These stones form very thick beds, up to nearly 5 m deep, that run in consistently parallel lines and have a dip angle that facilitates quarrying.With petrographic, physical and mechanical properties that ensure stone strength and durability, it is a high quality building material suitable for both structural and ornamental purposes. These properties can be attributed to the minimal open porosity and concomitant excellent water resistance that characterize the stone, as well as to its high mechanical strength and low textural anisotropy, both elastic and mechanical. With such attributes, the stone can be successfully used for any number of purposes, including decorative stonework (portals, fountains, plinths, structural members (column shafts and bases or urban curbing and paving. Intervention on Sierra de Elvira limestone structures should be limited to cleaning or repair, for consolidating or protective materials are scantly effective.La “Piedra de Sierra Elvira” constituye una de las piedras ornamentales más significativas del Patrimonio Arquitectónico de Andalucía Oriental. Es una roca caliza del Lias que aflora en el Subbético Medio del sector central de las Cordilleras Béticas. El litotipo más explotado es una caliza con crinoides, en bastante menor importancia se ha extraído también otra caliza micrítica de la misma edad. Los bancos son muy potentes, en algunos casos de más de 5 m, con un paralelismo constante y un buzamiento que favorece su explotación en los frentes de cantera.Sus caracter

  16. Limestone-Concentrate-Pellet Roasting in wet Carbon Dioxide

    Institute of Scientific and Technical Information of China (English)

    1990-01-01

    A roast process for treating chalcopyrite concentrate was developed. The investigation of the reaction of limestone-concentrate-pellet in a wet carbon dioxide flow was carried out by means of a thermogravimetric analysis (TGA) to determine at which temperatures the roasting reaction would take place. The thermodynamic calculations on the roast reaction were made by the use of SOLGASMIX-PV program. The TGA curves and thermodynamic calculations indicated that the conversion of chalcopyrite into bornite took place at about 975K, and the conversion of bornite into chalcocite at 1065-1123K. The thermodynamic calculations also showed that the sulfur released was fixed as calcium sulfide within roasted pellets. X-ray diffraction examination identified these phases in products.

  17. Experienced materials in wet limestone-gypsum FGD system

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, S. [Mitsubishi Heavy Industry, Hiroshima (Japan). Hiroshima Research and Development Center; Iwashita, K.; Ochi, E.; Higuchi, T. [Mitsubishi heavy Industry, Yokohama (Japan)

    1998-12-31

    This study was made on the corrosion resistivity evaluation method used for material selection in the Wet Limestone-Gypsum FGD system with examples of various process configuration, their corrosion environment, and the materials used in them. The wet limestone-gypsum process FGD plant is broadly divided into two types-ash-separated (dual-loop) process, and ash-mixed (single-loop) process-depending on whether the flue gas is separated from ash before being led into the absorber or led as it is into the absorber mixed with ash. Presently, the single-loop process has become the mainstream process however. The dual -loop process comprises a dedusting tower (quencher) and an absorption tower (absorber). In the quencher ash is removed with sprayed water where most of the HCl, HF etc., and a part of SO{sub x} and NO{sub x} contained in the flue gas are also removed with absorption. On the contrary, in the single-loop process which is configured of only the absorber, the flue gas is introduced into it as it is contained with ash, SO{sub x}, NO{sub x}, HCl, HF etc. The corrosion environment in these plants largely differs depending on the process type and condition. The absorber recirculated liquid has various ion inclusions among which Cl{sup {minus}} promotes pitting corrosion and crevice corrosion while SO{sub 4}{sup 2{minus}} inhibits these corrosions. Both Cl{sup {minus}} and SO{sub 4}{sup 2{minus}} cover an extremely large range between 25 to 100,000 ppm and 564 to 73,600 ppm respectively, and their influence on the corrosion is related to their activity which is decided by Ca{sup 2+}, Mg{sup 2+}, Na{sup +}, NH{sub 4}{sup +}, H{sup +} and liquid temperature. The balance of these ions is decided by the gas composition, limestone composition, make-up water and wastewater mass balance etc., of individual plants. Accordingly, materials of FGD plant are selected on the basis of evaluated results of corrosion resistivity test made under such simulated process conditions of

  18. SLAM: a sodium-limestone concrete ablation model

    International Nuclear Information System (INIS)

    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

  19. Geochemistry, environmental and provenance study of the Middle Miocene Leitha limestones (Central Paratethys)

    Science.gov (United States)

    Ali, Ahmed; Wagreich, Michael

    2017-06-01

    Mineralogical, major, minor, REE and trace element analyses of rock samples were performed on Middle Miocene limestones (Leitha limestones, Badenian) collected from four localities from Austria (Mannersdorf, Wöllersdorf, Kummer and Rosenberg quarries) and the Fertőrákos quarry in Hungary. Impure to pure limestones (i.e. limited by Al2O3 contents above or below 0.43 wt. %) were tested to evaluate the applicability of various geochemical proxies and indices in regard to provenance and palaeoenvironmental interpretations. Pure and impure limestones from Mannersdorf and Wöllersdorf (southern Vienna Basin) show signs of detrital input (REEs = 27.6 ± 9.8 ppm, Ce anomaly = 0.95 ± 0.1 and the presence of quartz, muscovite and clay minerals in impure limestones) and diagenetic influence (low contents of, e.g., Sr = 221 ± 49 ppm, Na is not detected, Ba = 15.6 ± 8.8 ppm in pure limestones). Thus, in both limestones the reconstruction of original sedimentary palaeoenvironments by geochemistry is hampered. The Kummer and Fertőrákos (Eisenstadt-Sopron Basin) comprise pure limestones (e.g., averages Sr = 571 ± 139 ppm, Na = 213 ± 56 ppm, Ba = 21 ± 4 ppm, REEs = 16 ± 3 ppm and Ce anomaly = 0.62 ± 0.05 and composed predominantly of calcite) exhibiting negligible diagenesis. Deposition under a shallow-water, well oxygenated to intermittent dysoxic marine environment can be reconstructed. Pure to impure limestones at Rosenberg-Retznei (Styrian Basin) are affected to some extent by detrital input and volcano-siliciclastic admixture. The Leitha limestones at Rosenberg have the least diagenetic influence among the studied localities (i.e. averages Sr = 1271 ± 261 ppm, Na = 315 ± 195 ppm, Ba = 32 ± 15 ppm, REEs = 9.8 ± 4.2 ppm and Ce anomaly = 0.77 ± 0.1 and consist of calcite, minor dolomite and quartz). The siliciclastic sources are characterized by immobile elemental ratios (i.e. La/Sc and Th/Co) which apply not only for the siliciclastics, but also for marls and

  20. Geochemistry, environmental and provenance study of the Middle Miocene Leitha limestones (Central Paratethys

    Directory of Open Access Journals (Sweden)

    Ali Ahmed

    2017-06-01

    Full Text Available Mineralogical, major, minor, REE and trace element analyses of rock samples were performed on Middle Miocene limestones (Leitha limestones, Badenian collected from four localities from Austria (Mannersdorf, Wöllersdorf, Kummer and Rosenberg quarries and the Fertőrákos quarry in Hungary. Impure to pure limestones (i.e. limited by Al2O3 contents above or below 0.43 wt. % were tested to evaluate the applicability of various geochemical proxies and indices in regard to provenance and palaeoenvironmental interpretations. Pure and impure limestones from Mannersdorf and Wöllersdorf (southern Vienna Basin show signs of detrital input (REEs = 27.6 ± 9.8 ppm, Ce anomaly = 0.95 ± 0.1 and the presence of quartz, muscovite and clay minerals in impure limestones and diagenetic influence (low contents of, e.g., Sr = 221 ± 49 ppm, Na is not detected, Ba = 15.6 ± 8.8 ppm in pure limestones. Thus, in both limestones the reconstruction of original sedimentary palaeoenvironments by geochemistry is hampered. The Kummer and Fertőrákos (Eisenstadt–Sopron Basin comprise pure limestones (e.g., averages Sr = 571 ± 139 ppm, Na = 213 ± 56 ppm, Ba = 21 ± 4 ppm, REEs = 16 ± 3 ppm and Ce anomaly = 0.62 ± 0.05 and composed predominantly of calcite exhibiting negligible diagenesis. Deposition under a shallow-water, well oxygenated to intermittent dysoxic marine environment can be reconstructed. Pure to impure limestones at Rosenberg–Retznei (Styrian Basin are affected to some extent by detrital input and volcano-siliciclastic admixture. The Leitha limestones at Rosenberg have the least diagenetic influence among the studied localities (i.e. averages Sr = 1271 ± 261 ppm, Na = 315 ± 195 ppm, Ba = 32 ± 15 ppm, REEs = 9.8 ± 4.2 ppm and Ce anomaly = 0.77 ± 0.1 and consist of calcite, minor dolomite and quartz. The siliciclastic sources are characterized by immobile elemental ratios (i.e. La/Sc and Th/Co which apply not only for the siliciclastics, but also

  1. Electrokinetically Enhanced Delivery for ERD Remediation of Chlorinated Ethenes in a Fractured Limestone Aquifer

    DEFF Research Database (Denmark)

    Broholm, Mette Martina; Hyldegaard, Bente Højlund; With Nedergaard, Lærke

    causing very long remediation timeframes. Electrokinetics (EK) offers some unique transport processes, which can potentially overcome the diffusion limitations in the matrix. A novel technology combines ERD and EK for enhanced delivery. The combined technology (EK-BIO) has shown promising results in clay....... Experimental work on EK-BIO in limestone was conducted in a laboratory setup with limestone cores. EK was demonstrated to be promising in establishing enhanced contact between the donor lactate, bacteria, and cis-DCE within the limestone matrix. Complete dechlorination is expected to take place in the matrix......, since back diffusion limitations in the limestone matrix are overcome. This is essential for the overall time perspective of a remediation in limestone aquifers....

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

    Energy Technology Data Exchange (ETDEWEB)

    Neil, L.L.; McCullough, C.D.; Lund, M.A.; Evans, L.H.; Tsvetnenko, Y. [Edith Cowan University, Joondalup, WA (Australia)

    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.

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

    Science.gov (United States)

    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.

  4. Hydration mechanisms of ternary Portland cements containing limestone powder and fly ash

    International Nuclear Information System (INIS)

    De Weerdt, K.; Haha, M. Ben; Le Saout, G.; Kjellsen, K.O.; Justnes, H.; Lothenbach, B.

    2011-01-01

    The effect of minor additions of limestone powder on the properties of fly ash blended cements was investigated in this study using isothermal calorimetry, thermogravimetry (TGA), X-ray diffraction (XRD), scanning electron microscopy (SEM) techniques, and pore solution analysis. The presence of limestone powder led to the formation of hemi- and monocarbonate and to a stabilisation of ettringite compared to the limestone-free cements, where a part of the ettringite converted to monosulphate. Thus, the presence of 5% of limestone led to an increase of the volume of the hydrates, as visible in the increase in chemical shrinkage, and an increase in compressive strength. This effect was amplified for the fly ash/limestone blended cements due to the additional alumina provided by the fly ash reaction.

  5. Optimisation of a wet FGD pilot plant using fine limestone and organic acids

    DEFF Research Database (Denmark)

    Frandsen, Jan; Kiil, Søren; Johnsson, Jan Erik

    2001-01-01

    , but the residual limestone content in the gypsum increased to somewhere between 19 and 30 wt%, making this pH range unsuitable for use in a full-scale plant. The investigations have shown that both the addition of organic acids and the use of a limestone with a fine PSD can be used to optimise wet FGD plants. (C......The effects of adding an organic acid or using a limestone with a fine particle size distribution (PSD) have been examined in a wet flue gas desulphurisation (FGD) pilot plant. Optimisation of the plant with respect to the degree of desulphurisation and the residual limestone content of the gypsum...... has been the aim of the work. In contrast to earlier investigations with organic acids, all essential process parameters (i.e. gas phase concentration profiles of SO(2), slurry pH profiles. and residual limestone in the gypsum) were considered. Slurry concentrations of adipic acid in the range of 0...

  6. French public finances at risk?

    Directory of Open Access Journals (Sweden)

    Creel Jérôme

    2014-01-01

    Full Text Available Using descriptive evidence, this paper contributes to the debate on French public finances’ consolidation by examining the long-term sustainability of France’s fiscal position. We trace the historical trends of government’s tax receipts and expenditures. We illustrate that while the level of public expenditure in France is larger than in the Euro Area, its trend is comparable to its neighbours. French net debt is comparable to Eurozone’s while French net wealth remains positive. However, the French tax system is not progressive with only 6% of compulsory levies raised that way, and too complex. The paper then acknowledges the efficient debt management of French authorities. As a conclusion, we see no risk of future unsustainability linked to the nature or the level of current French public finances.

  7. Future of French refining

    International Nuclear Information System (INIS)

    Calvet, B.

    1993-01-01

    Over recent years, the refining industry has had to grapple with a growing burden of environmental and safety regulations concerning not only its plants and other facilities, but also its end products. At the same time, it has had to bear the effects of the reduction of the special status that used to apply to petroleum, and the consequences of economic freedom, to which we should add, as specifically concerns the French market, the impact of energy policy and the pro-nuclear option. The result is a drop in heavy fuel oil from 36 million tonnes per year in 1973 to 6.3 million in 1992, and in home-heating fuel from 37 to 18 million per year. This fast-moving market is highly competitive. The French market in particular is wide open to imports, but the refining companies are still heavy exporters for those products with high added-value, like lubricants, jet fuel, and lead-free gasolines. The competition has led the refining companies to commit themselves to quality, and to publicize their efforts in this direction. This is why the long-term perspectives for petroleum fuels are still wide open. This is supported by the probable expectation that the goal of economic efficiency is likely to soften the effects of the energy policy, which penalizes petroleum products, in that they have now become competitive again. In the European context, with the challenge of environmental protection and the decline in heavy fuel outlets, French refining has to keep on improving the quality of its products and plants, which means major investments. The industry absolutely must return to a more normal level of profitability, in order to sustain this financial effort, and generate the prosperity of its high-performance plants and equipment. 1 fig., 5 tabs

  8. [French immigration policy].

    Science.gov (United States)

    Weil, P

    1994-01-01

    From the late nineteenth century through 1974, France permitted immigration to furnish workers and to compensate for the low level of fertility. Intense immigration from North Africa, the economic crisis of the 1970s, and other factors led to policy changes in 1974. French immigration policy since 1974 has fluctuated between guaranteeing foreigners equal rights regardless of their religion, race, culture, or national origin, and attempting to differentiate among immigrants depending on their degree of assimilability to French culture. From 1974 to 1988, France had five different policies regarding whether to permit new immigration and what to do about illegal immigrants. In July 1984, the four major political parties unanimously supported a measure in Parliament that definitively guaranteed the stay in France of legal immigrants, whose assimilation thus assumed priority. Aid for return to the homeland was no longer to be widely offered, and immigration of unskilled workers was to be terminated except for those originating in European Community countries. Major changes of government in 1988 and 1993 affected only the modalities of applying these principles. The number of immigrants has fluctuated since 1974. Unskilled workers, the only category whose entrance was specifically controlled by the 1984 measures, have declined from 174,000 in 1970 to 25,000 in the early 1990s. The number of requests for political asylum declined from 60,000 in 1989 to 27,000 in 1993, and in 1991, 15,467 persons were granted refugee status. The number of immigrants of all types permitted to remain in France declined from 250,000 or 3000 per year in the early 1970s to around 110,000 at present. Although the decline is significant, it appears insufficient to the government in power since 1993. Although migratory flows are often explained as the product of imbalance in the labor market or in demographic growth, the French experience suggests that government policies, both in the sending and

  9. The French dosimetry protocol

    International Nuclear Information System (INIS)

    Dutreix, A.

    1985-01-01

    After a general introduction the protocol is divided in five sections dealing with: determination of the quality of X-ray, γ-ray and electron beams; the measuring instrument; calibration of the reference instrument; determination of the reference absorbed dose in the user's beams; determination of the absorbed dose in water at other points, in other conditions. The French protocol is not essentially different from the Nordic protocol and it is based on the experience gained in using both the American and the Nordic protocols. Therefore, only the main difference with the published protocols are discussed. (Auth.)

  10. 1001 easy French phrases

    CERN Document Server

    McCoy, Heather

    2010-01-01

    The perfect companion for tourists and business travelers in France and other places where the French language is spoken, this book offers fast, effective communication. More than 1,000 basic words, phrases, and sentences cover everything from asking directions and renting a car to ordering dinner and finding a bank.Designed as a quick reference tool and an easy study guide, this inexpensive and easy-to-use book offers completely up-to-date terms for modern telecommunications, idioms, and slang. The contents are arranged for quick access to phrases related to greetings, transportation, shoppin

  11. The french criticality handbook

    International Nuclear Information System (INIS)

    Maubert, L.; Puit, J.C.

    1987-01-01

    The french criticality handbook, published in 1978 by the ''Commissariat a l'Energie Atomique'', is presented with the main targets aimed by the writer and the main choices taken relating to fissile mediums, reflection conditions, dilution curves. The validation of the critical values is presented as one of the most important aspects of this handbook which is mainly intended, in the mind of the author, to specialists well advertised in the field of criticality. The complements which have been introduced since 1978 and those which are foreseen in a near future are also detailed. (author)

  12. French in Culinary World

    OpenAIRE

    Rila Hilma

    2011-01-01

    More than million foods have been made by people from all over the world in the latest years. People now try to create new cooks and make some creativity on it. Then, cooking which the field is culinary has become an art because it needs an artistic value to decorate the food, a good taste and proper technique in processing delicious food in order to make it a masterpiece. French culinary is as famous as the Eiffel tower in the heart of the country, Paris. Most of fine dining international re...

  13. FRENCH PROTOCOL CARDS

    CERN Multimedia

    Division du Personnel

    1999-01-01

    Senior officials, holders of FRENCH PROTOCOL cards (blue cards) due to expire on 31.12.1999, are requested to return these cards and those of family members, for extension to:Bureau des cartes, bâtiment 33.1-025Should the 3 spaces for authentication on the back of the card be full, please enclose 2 passport photographs for a new card.In the case of children aged 14 and over, an attestation of dependency and a school certificate should be returned with the card.Personnel DivisionTel. 79494/74683

  14. FRENCH PROTOCOL CARDS

    CERN Multimedia

    Human Resources Division

    2000-01-01

    Senior officials, holders of FRENCH PROTOCOL cards (blue cards) due to expire on 31.12.2000, are requested to return these cards and those of family members, for extension to: Bureau des cartes, Bât 33.1-009/1-015 Should the three spaces for authentication on the back of the card be full, please enclose two passport photographs for a new card. In the case of children aged 14 and over, an attestation of dependency and a school certificate should be returned with the card.

  15. CLEANING OF FRENCH SITES

    CERN Multimedia

    Mauro Nonis

    2002-01-01

    In the last two weeks some cleaning problems have been remarked in several CERN buildings on the French part of CERN sites. This is mainly due to the start up of the new cleaning contract from the 1st July. These problems are not related to a budgetary reduction of the activity. We excuse for the malfunctions that have been created to CERN community and we assure you that we have taken all the needed measures to solve the problem in the shortest delay. Mauro Nonis (ST/FM)

  16. French electricity results 2002

    International Nuclear Information System (INIS)

    2002-01-01

    RTE, the manager of the French power system, announces a high increase in electricity exports to the other countries of the European Union in 2002. In France, the year 2002 was marked by stable power consumption, but a noteworthy increase in generation due to the rise of exports. In 2002, the RTE network conveyed 512.3 billion kWh (TWh) versus 503.1 billion kWh (TWh) in 2001, an increase of 1.8%. Overall French exports made considerable strides forward from 72.9 TWh in 2001 to 80.6 TWh in 2002, i.e. 10.6% more than in 2001. On the other hand, overall French imports fell substantially, from 4.4 TWh in 2001 to 3.8 TWh in 2002, or a drop of about 14%. In all, the export balance came to 76.8 TWh in 2002, versus 68.5 TWh in 2001, i.e. a rise of 12%. On Sunday, 22 December 2002, the historical record of the capacity export balance with a value of 13,277 MW, up 2.2%, was bettered. The particularly mild weather conditions in 2002 led to a drop in heating-related consumption, evaluated at 7 billion kWh compared with the prior year. A slight upturn in industrial consumption was to be noted, from 92.7 TWh in 2001 to 93.2 TWh in 2002, i.e. a growth of 0.5%. Total French consumption thus rose in 2002 to 448.7 TWh. Total consumption, adjusted for climate contingencies, showed a rise of 1.6% in 2002. French power producers showed an increase of nearly 2% and the first wind farm was connected to the power transmission network. French electricity output came to 532.9 TWh in 2002, a growth of 1.9%. This increase is divided up between nuclear generation, up 4%, and conventional thermal generation, on the rise by 15.3%. The substantial share of thermal generation can be explained by a correlative drop in hydro generation (less 16.6% compared with 2001) mainly due to extremely low water availability observed during the first months of the year. With 415.5 TWh in output, nuclear power plants provided 78% of French generation, fossil-fired power plants 9.9% with an output of 52.9 TWh

  17. The French nuclear context

    International Nuclear Information System (INIS)

    Havard, J.; Israel, M.

    1977-01-01

    The mean- and longer-range energy needs, that can be now forecasted in France, are analyzed, together with the special character of the French energy market. A resort to nuclear power is first shown to be necessary to limit the increase in the demand for imported fossil fuels, then this resort is shown to offer some real possibilities. The energy balance proves that the industrial stage of power plant construction is reached. The conditions of realization of the program have been settled with a set of provisions that render the risk and environmental impact as negligible as possible [fr

  18. The Mississippian Leadville Limestone Exploration Play, Utah and Colorado-Exploration Techniques and Studies for Independents

    Energy Technology Data Exchange (ETDEWEB)

    Thomas Chidsey

    2008-09-30

    -marine facies constitute a significant reservoir potential, having both effective porosity and permeability when dissolution of skeletal grains, followed by dolomitization, has occurred. Two major types of diagenetic dolomite are observed in the Leadville Limestone at Lisbon field: (1) tight 'early' dolomite consisting of very fine grained (<5 {micro}m), interlocking crystals that faithfully preserve depositional fabrics; and (2) porous, coarser (>100-250 {micro}m), rhombic and saddle crystals that discordantly replace limestone and earlier very fine grained dolomite. Predating or concomitant with late dolomite formation are pervasive leaching episodes that produced vugs and extensive microporosity. Most reservoir rocks within Lisbon field appear to be associated with the second, late type of dolomitization and associated leaching events. Other diagenetic products include pyrobitumen, syntaxial cement, sulfide minerals, anhydrite cement and replacement, and late macrocalcite. Fracturing (solution enlarged) and brecciation (autobrecciation) caused by hydrofracturing are widespread within Lisbon field. Sediment-filled cavities, related to karstification of the exposed Leadville, are present in the upper third of the formation. Pyrobitumen and sulfide minerals appear to coat most crystal faces of the rhombic and saddle dolomites. The fluid inclusion and mineral relationships suggest the following sequence of events: (1) dolomite precipitation, (2) anhydrite deposition, (3) anhydrite dissolution and quartz precipitation, (4) dolomite dissolution and late calcite precipitation, (5) trapping of a mobile oil phase, and (6) formation of bitumen. Fluid inclusions in calcite and dolomite display variable liquid to vapor ratios suggesting reequilibration at elevated temperatures (50 C). Fluid salinities exceed 10 weight percent NaCl equivalent. Low ice melting temperatures of quartz- and calcite-hosted inclusions suggest chemically complex Ca-Mg-bearing brines associated with

  19. Invitation Refusals in Cameroon French and Hexagonal French

    Science.gov (United States)

    Farenkia, Bernard Mulo

    2015-01-01

    Descriptions of regional pragmatic variation in French are lacking to date the focus has been on a limited range of speech acts, including apologies, requests, compliments and responses to compliments. The present paper, a systematic analysis of invitation refusals across regional varieties of French, is designed to add to the research on…

  20. Language Training: French Training

    CERN Multimedia

    2004-01-01

    If you wish to participate in one of the following courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at: http://www.cern.ch/Training/ or fill in an "application for training" form available from your Divisional Secretariat or from your DTO (Divisional Training Officer). Applications will be accepted in the order of their receipt. LANGUAGE TRAINING Françoise Benz tel. 73127 language.training@cern.ch General and Professional French Courses The next session will take place from 26 April to 02 July 2004. These courses are open to all persons working on the Cern site, and to their spouses. For registration and further information on the courses, please consult our Web pages: http://cern.ch/Training or contact Mrs. Benz: Tel. 73127. Writing Professional Documents in French The next session will take place from 26 April to 02 July 2004. This course is designed for people with a good level of s...

  1. Language Training: French Training

    CERN Multimedia

    2004-01-01

    If you wish to participate in one of the following courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at: http://www.cern.ch/Training/ or fill in an "application for training" form available from your Divisional Secretariat or from your DTO (Divisional Training Officer). Applications will be accepted in the order of their receipt. LANGUAGE TRAINING Françoise Benz tel. 73127 language.training@cern.ch General and Professional French Courses The next session will take place from 26 April to 02 July 2004. These courses are open to all persons working on the Cern site, and to their spouses. For registration and further information on the courses, please consult our Web pages: http://cern.ch/Training or contact Mrs. Benz: Tel. 73127. Writing Professional Documents in French The next session will take place from 26 April to 02 July 2004. This course is designed for people with a good level...

  2. Spotlight: French Polynesia.

    Science.gov (United States)

    May, J F

    1988-01-01

    French Polynesia is a group of 4 archipelagos in the South Pacific with an estimated 1987 population of 176,600. Its people are mainly Tahitians, Polynesians, Chinese, Europeans, and persons of mixed heritage. More than half of the population live in the Society Islands. About half of the population is less than 20 years old and slightly more than 5% is older than 60. Due to a recent decline in fertility, the rate of natural increase is moderate--about 2.5% annually. In the early 1980s, about two thirds of women in Tahiti aged 15-49 used a modern method of contraception. It remains to be seen whether this pattern will spread to the entire area. Projections by the World Bank, assuming little decline in mortality, yield a total population of 400,000 by the year 2030. The major challenge for French Polynesia is to develop the many small islands spread across an ocean territory half the size of the contiguous 48 states of the U.S. Tourist-related activities have replaced traditional income-generating such as production of coconuts, mother-of-pearl, and vanilla. The value of exports from the area make up only 5% of the value of imports. To extract the potentially huge food and mineral resources from the ocean, enormous infusions of capital will be necessary.

  3. The French capacity mechanism

    International Nuclear Information System (INIS)

    2014-01-01

    The French capacity mechanism has been design to ensure security of supply in the context of the energy transition. This energy transition challenges the electricity market design with several features: peak load growth, the development of renewables, demand response,... To ensure security of supply in this context, a capacity mechanism is being implemented in France. It is a market wide capacity obligation on electricity suppliers, based on market principles. Suppliers are responsible for forecasting their obligation, which corresponds to their contribution to winter peak load, and must procure enough capacity certificates to meet their obligations. Capacity certificates are granted to capacities through a certification process, which assesses their contribution to security of supply on the basis of availability commitments. This certification process is technology neutral and performance based, associated with controls and penalties in case of non compliance. Demand Side is fully integrated in the market, either through the reduction of suppliers' capacity obligation or direct participation after certification. In addition to the expected benefits in terms of security of supply, the French capacity market will foster the development of demand response. The participation of foreign capacities will require adaptations which are scheduled in a road-map, and could pave the way for further European integration of energy policies. (authors)

  4. French intensive truck garden

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, T D

    1983-01-01

    The French Intensive approach to truck gardening has the potential to provide substantially higher yields and lower per acre costs than do conventional farming techniques. It was the intent of this grant to show that there is the potential to accomplish the gains that the French Intensive method has to offer. It is obvious that locally grown food can greatly reduce transportation energy costs but when there is the consideration of higher efficiencies there will also be energy cost reductions due to lower fertilizer and pesticide useage. As with any farming technique, there is a substantial time interval for complete soil recovery after there have been made substantial soil modifications. There were major crop improvements even though there was such a short time since the soil had been greatly disturbed. It was also the intent of this grant to accomplish two other major objectives: first, the garden was managed under organic techniques which meant that there were no chemical fertilizers or synthetic pesticides to be used. Second, the garden was constructed so that a handicapped person in a wheelchair could manage and have a higher degree of self sufficiency with the garden. As an overall result, I would say that the garden has taken the first step of success and each year should become better.

  5. Wind: French revolutions

    International Nuclear Information System (INIS)

    Jones, C.

    2006-01-01

    Despite having the second best wind resources in Europe after the UK, the wind industry in France lags behind its European counterparts with just 6 W of installed wind capacity per person. The electricity market in France is dominated by the state-owned Electricite de France (EdF) and its nuclear power stations. However, smaller renewable generators are now in theory allowed access to the market and France has transposed the EU renewables directive into national law. The French governement has set a target of generating 10,000 MW of renewable capacity by 2010. The announcement of an increased feed-in tariff and the introduction of 'development zones' (ZDEs) which could allow fast-tracking of planning for wind projects are also expected to boost wind projects. But grid access and adminstrative burdens remain major barriers. In addition, French politicians and local authorities remain committed to nuclear, though encouraged by the European Commission, wind is beginning to gain acceptance; some 325 wind farms (representing 1557 MW of capacity) were approved between February 2004 and January 2005. France is now regarded by the international wind energy sector as a target market. One of France's leading independent wind developers and its only listed wind company, Theolia, is expected to be one of the major beneficiaries of the acceleration of activity in France, though other companies are keen to maximise the opportunities for wind. France currently has only one indigenous manufacturer of wind turbines, but foreign suppliers are winning orders

  6. Smart grids - French Expertise

    International Nuclear Information System (INIS)

    2015-11-01

    The adaptation of electrical systems is the focus of major work worldwide. Bringing electricity to new territories, modernizing existing electricity grids, implementing energy efficiency policies and deploying renewable energies, developing new uses for electricity, introducing electric vehicles - these are the challenges facing a multitude of regions and countries. Smart Grids are the result of the convergence of electrical systems technologies with information and communications technologies. They play a key role in addressing the above challenges. Smart Grid development is a major priority for both public and private-sector actors in France. The experience of French companies has grown with the current French electricity system, a system that already shows extensive levels of 'intelligence', efficiency and competitiveness. French expertise also leverages substantial competence in terms of 'systems engineering', and can provide a tailored response to meet all sorts of needs. French products and services span all the technical and commercial building blocks that make up the Smart Grid value chain. They address the following issues: Improving the use and valuation of renewable energies and decentralized means of production, by optimizing the balance between generation and consumption. Strengthening the intelligence of the transmission and distribution grids: developing 'Supergrid', digitizing substations in transmission networks, and automating the distribution grids are the focus of a great many projects designed to reinforce the 'self-healing' capacity of the grid. Improving the valuation of decentralized flexibilities: this involves, among others, deploying smart meters, reinforcing active energy efficiency measures, and boosting consumers' contribution to grid balancing, via practices such as demand response which implies the aggregation of flexibility among residential, business, and/or industrial sites. Addressing current technological challenges, in

  7. Modeling of Hydration, Compressive Strength, and Carbonation of Portland-Limestone Cement (PLC Concrete

    Directory of Open Access Journals (Sweden)

    Xiao-Yong Wang

    2017-01-01

    Full Text Available Limestone is widely used in the construction industry to produce Portland limestone cement (PLC concrete. Systematic evaluations of hydration kinetics, compressive strength development, and carbonation resistance are crucial for the rational use of limestone. This study presents a hydration-based model for evaluating the influences of limestone on the strength and carbonation of concrete. First, the hydration model analyzes the dilution effect and the nucleation effect of limestone during the hydration of cement. The degree of cement hydration is calculated by considering concrete mixing proportions, binder properties, and curing conditions. Second, by using the gel–space ratio, the compressive strength of PLC concrete is evaluated. The interactions among water-to-binder ratio, limestone replacement ratio, and strength development are highlighted. Third, the carbonate material contents and porosity are calculated from the hydration model and are used as input parameters for the carbonation model. By considering concrete microstructures and environmental conditions, the carbon dioxide diffusivity and carbonation depth of PLC concrete are evaluated. The proposed model has been determined to be valid for concrete with various water-to-binder ratios, limestone contents, and curing periods.

  8. Biotin- and Glycoprotein-Coated Microspheres as Surrogates for Studying Filtration Removal of Cryptosporidium parvum in a Granular Limestone Aquifer Medium.

    Science.gov (United States)

    Stevenson, M E; Blaschke, A P; Toze, S; Sidhu, J P S; Ahmed, W; van Driezum, I H; Sommer, R; Kirschner, A K T; Cervero-Aragó, S; Farnleitner, A H; Pang, L

    2015-07-01

    Members of the genus Cryptosporidium are waterborne protozoa of great health concern. Many studies have attempted to find appropriate surrogates for assessing Cryptosporidium filtration removal in porous media. In this study, we evaluated the filtration of Cryptosporidium parvum in granular limestone medium by the use of biotin- and glycoprotein-coated carboxylated polystyrene microspheres (CPMs) as surrogates. Column experiments were carried out with core material taken from a managed aquifer recharge site in Adelaide, Australia. For the experiments with injection of a single type of particle, we observed the total removal of the oocysts and glycoprotein-coated CPMs, a 4.6- to 6.3-log10 reduction of biotin-coated CPMs, and a 2.6-log10 reduction of unmodified CPMs. When two different types of particles were simultaneously injected, glycoprotein-coated CPMs showed a 5.3-log10 reduction, while the uncoated CPMs displayed a 3.7-log10 reduction, probably due to particle-particle interactions. Our results confirm that glycoprotein-coated CPMs are the most accurate surrogates for C. parvum; biotin-coated CPMs are slightly more conservative, while unmodified CPMs are markedly overly conservative for predicting C. parvum removal in granular limestone medium. The total removal of C. parvum observed in our study suggests that granular limestone medium is very effective for the filtration removal of C. parvum and could potentially be used for the pretreatment of drinking water and aquifer storage recovery of recycled water. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  9. Diversity and biogeography of land snails (Mollusca, Gastropoda) in the limestone hills of Perak, Peninsular Malaysia

    Science.gov (United States)

    Foon, Junn Kitt; Clements, Gopalasamy Reuben; Liew, Thor-Seng

    2017-01-01

    Abstract Limestone hills are now gaining global conservation attention as hotspots for short-range endemic species. Levels of land snail endemism can be high at limestone hills, especially at hill clusters that are geographically isolated. In the State of Perak, Peninsular Malaysia, limestone hills have been opportunistically surveyed for land snails in the past, but the majority have yet to be surveyed. To address this knowledge gap, we systematically surveyed the terrestrial malacofauna of 12 limestone hills that, based on our opinion, are a representation of the limestone land snail assemblages within the State. Our inventory yielded high sampling completeness (>85%). We found 122 species of land snails, of which 34 species were unique to one of the surveyed hills. We identified 30 species that are potentially new to science. The number of land snail species recorded at each hill ranged between 39 and 63 species. Four of the sampled limestone hills namely, Prk 01 G. Tempurung, Prk 55 G. Pondok, Prk 47 Kanthan, and Prk 64 Bt Kepala Gajah, have high levels of species richness and unique species, representing 91% of the total species recorded in this study. We identified two clusters of limestone hills in central Perak with distinct differences in land snail species composition – a northern hill cluster on elevated granite bedrock and southern hill cluster in a low-lying valley surrounded by alluvial soils. As limestone hills continue to be quarried to meet the cement demand, the four identified limestone hills, along with other hills from the two clusters, warrant urgent conservation attention in order to maintain high species diversity within Perak’s terrestrial malacofauna. PMID:28769723

  10. Capture of SO2 by limestone in a 71 MWe pressurized fluidized bed boiler

    Directory of Open Access Journals (Sweden)

    Shimizu Tadaaki

    2003-01-01

    Full Text Available A 71 MWe pressurized fluidized bed coal combustor was operated. A wide variety of coals were burnt under fly ash recycle conditions. Limestone was fed to the combustor as bed material as well as sorbent. The emission of SO^ and limestone attrition rate were measured. A simple mathematical model of SO? capture by limestone with intermittent solid attrition was applied to the analysis of the present experimental results. Except for high sulfur fuel, the results of the present model agreed with the experimental results.

  11. CARBONIFEROUS CORALS AND CHAETETIDS FROM EXOTIC LIMESTONE BLOCK OF THE CRIMEA

    Directory of Open Access Journals (Sweden)

    VICTOR OGAR

    2015-11-01

    Full Text Available A chaetetid sponge and coral fauna from a Carboniferous exotic limestone block in the Lower Jurassic Esciorda olistostrome on the Bodrak River (Crimean Mountains are described for the first time. The Bodrak exotic block is composed of massive limestone. It contains the chaetetid Chaetetes (Boswellia sp., the tabulate coral Multithecopora sp., and poorly preserved rugose corals, including Dibunophyllum? sp., Cordibia? sp. and gen. et sp. indet. Only the fasciculate colonies of the rugose coral Lytvophyllum askynensis (Kossovaya, 2009 are confidently identified. The studied association of fossils is similar to that of the Donets Basin and the Urals and confirms the Lower Bashkirian age of the Bodrak limestone block. 

  12. Foams in porous media

    Energy Technology Data Exchange (ETDEWEB)

    Marsden, S.S.

    1986-07-01

    In 1978 a literature search on selective blocking of fluid flow in porous media was done by Professor S.S. Marsden and two of his graduate students, Tom Elson and Kern Huppy. This was presented as SUPRI Report No. TR-3 entitled ''Literature Preview of the Selected Blockage of Fluids in Thermal Recovery Projects.'' Since then a lot of research on foam in porous media has been done on the SUPRI project and a great deal of new information has appeared in the literature. Therefore we believed that a new, up-to-date search should be done on foam alone, one which would be helpful to our students and perhaps of interest to others. This is a chronological survey showing the development of foam flow, blockage and use in porous media, starting with laboratory studies and eventually getting into field tests and demonstrations. It is arbitrarily divided into five-year time periods. 81 refs.

  13. Porous material neutron detector

    Science.gov (United States)

    Diawara, Yacouba [Oak Ridge, TN; Kocsis, Menyhert [Venon, FR

    2012-04-10

    A neutron detector employs a porous material layer including pores between nanoparticles. The composition of the nanoparticles is selected to cause emission of electrons upon detection of a neutron. The nanoparticles have a maximum dimension that is in the range from 0.1 micron to 1 millimeter, and can be sintered with pores thereamongst. A passing radiation generates electrons at one or more nanoparticles, some of which are scattered into a pore and directed toward a direction opposite to the applied electrical field. These electrons travel through the pore and collide with additional nanoparticles, which generate more electrons. The electrons are amplified in a cascade reaction that occurs along the pores behind the initial detection point. An electron amplification device may be placed behind the porous material layer to further amplify the electrons exiting the porous material layer.

  14. Porous Silicon Nanowires

    Science.gov (United States)

    Qu, Yongquan; Zhou, Hailong; Duan, Xiangfeng

    2011-01-01

    In this minreview, we summarize recent progress in the synthesis, properties and applications of a new type of one-dimensional nanostructures — single crystalline porous silicon nanowires. The growth of porous silicon nanowires starting from both p- and n-type Si wafers with a variety of dopant concentrations can be achieved through either one-step or two-step reactions. The mechanistic studies indicate the dopant concentration of Si wafers, oxidizer concentration, etching time and temperature can affect the morphology of the as-etched silicon nanowires. The porous silicon nanowires are both optically and electronically active and have been explored for potential applications in diverse areas including photocatalysis, lithium ion battery, gas sensor and drug delivery. PMID:21869999

  15. Development of the French Photovoltaic Program

    Energy Technology Data Exchange (ETDEWEB)

    Brunet, M.

    1980-07-01

    The French photovoltaic research program is reviewed, listing companies involved. Projections of module and system costs are discussed. French industrial experience in photovoltaics is reviewed and several French systems operating in developing countries are mentioned. (MHR)

  16. General and Professional French Courses

    CERN Multimedia

    HR Department

    2010-01-01

    The next session will take place from 11 October to 17 December 2010. These courses are open to all persons working on the CERN site, and to their spouses. For registration and further information on the courses, please consult our Web pages: http://cern.ch/Training or contact Mrs. Nathalie Dumeaux, tel. 78144. NEW COURSES Specific French courses -Exam preparation/ We are now offering specific courses in English and French leading to a recognised external examination (e.g. DELF 1 and 2). If you are interested in following one of these courses and have at least an intermediate level of French, please enrol through the following link: French courses or contact: Lucette Fournier, tel.  73483 (French courses).

  17. Porous silicon gettering

    Energy Technology Data Exchange (ETDEWEB)

    Tsuo, Y.S.; Menna, P.; Pitts, J.R. [National Renewable Energy Lab., Golden, CO (United States)] [and others

    1996-05-01

    The authors have studied a novel extrinsic gettering method that uses the large surface areas produced by a porous-silicon etch as gettering sites. The annealing step of the gettering used a high-flux solar furnace. They found that a high density of photons during annealing enhanced the impurity diffusion to the gettering sites. The authors used metallurgical-grade Si (MG-Si) prepared by directional solidification casing as the starting material. They propose to use porous-silicon-gettered MG-Si as a low-cost epitaxial substrate for polycrystalline silicon thin-film growth.

  18. Radon in the Creswell Crags Permian limestone caves

    International Nuclear Information System (INIS)

    Gillmore, G.K.; Phillips, P.S.; Denman, A.R.; Gilbertson, D.D.

    2002-01-01

    An investigation of radon levels in the caves of Creswell Crags, Derbyshire, an important Site of Special Scientific Interest (SSSI) shows that the Lower Magnesian Limestone (Permian) caves have moderate to raised radon gas levels (27-7800 Bq m -3 ) which generally increase with increasing distance into the caves from the entrance regions. This feature is partly explained in terms of cave ventilation and topography. While these levels are generally below the Action Level in the workplace (400 Bq m -3 in the UK), they are above the Action Level for domestic properties (200 Bq m -3 ). Creswell Crags has approximately 40,000 visitors per year and therefore a quantification of effective dose is important for both visitors and guides to the Robin Hood show cave. Due to short exposure times the dose received by visitors is low (0.0016 mSv/visit) and regulations concerning exposure are not contravened. Similarly, the dose received by guides is fairly low (0.4 mSv/annum) due in part to current working practice. However, the risk to researchers entering the more inaccessible areas of the cave system is higher (0.06 mSv/visit). This survey also investigated the effect of seasonal variations on recorded radon concentration. From this work summer to winter ratios of between 1.1 and 9.51 were determined for different locations within the largest cave system

  19. Environmental impact management during construction of the limestone project

    International Nuclear Information System (INIS)

    Windsor, D.C.

    1988-01-01

    The Limestone Generating Station is being constructed on the Nelson River in Northern Manitoba, and will consist of a 10 unit powerhouse, 5 gate concrete spillway and earthfill dam spanning the 1.5 km width of the Nelson River. Environmental concerns associated with the project included insufficient pre- and post-construction monitoring documenting resources present or magnitude of impacts, impacts on brook trout and lake sturgeon resources, wildlife habitat loss due to construction activities, destruction or disturbance of historic or archaeological sites, degradation of nearby water courses and fish habitat by aggregate removal, in-migration of construction personnel, and various other socio-economic impacts. An overview is provided of monitoring activities and results in the above areas, which involved numerous consultants and government agencies. The project administration and workers did not find the environmental programs, including inspection and enforcement activities, to be onerous or an impediment to the project. On the contrary, the environmental requirements assisted in the general planning for certain activities, and in the general criteria for the conduct of the activities. The work permit process was particularly useful as it defined the requirements of both parties and provided the specific standards necessary determining the acceptability of the activities. 14 refs., 1 fig

  20. Transport studies of radon in limestone underlying houses

    International Nuclear Information System (INIS)

    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

  1. Interaction and penetration of heated UO2 with limestone concrete

    International Nuclear Information System (INIS)

    Farhadieh, R.; Pedersen, D.R.; Purviance, R.; Carlson, N.

    1982-01-01

    To safeguard the environment against radiological releases, the major question of concern in PAHR safety assessment, following an HCDA, involves confinement and dilution of the molten core-debris. Significant to the study is the directional growth of the core-debris in the concrete foundation of the reactor building or the concrete below the reactor cavity. The real material experiments were carried out in the test apparatus shown. Casts of CRBRP limestone concrete were prepared in graphite cylinders, each having an internal diameter of 8.9 cm and a depth of 30.5 cm. The 17.8-cm-deep concrete samples were allowed to cure for at least 28 days. Experiments were conducted within two months of curing time. The cavity above concrete was packed with 3 kg of pure UO 2 particles (1 to 3 mm). A uranothermic mixture was placed on the top of UO 2 powder. Heating and possible melting of UO 2 was achieved resistively after the ignition of the thermite. Total experimental time was about 60 minutes, during which time a maximum electrical power input of 1.8 watts/gr was applied to the UO 2 . Three gas samples were taken at temperatures of 100, 600, and 950 0 C, measured in the plane of the No. 2 thermocouple. Selection of three temperatures were to study the amount and the type of gases released from different phases of concrete

  2. Status of French reactors

    Energy Technology Data Exchange (ETDEWEB)

    Ballagny, A. [Commissariat a l`Energie Atomique, Saclay (France)

    1997-08-01

    The status of French reactors is reviewed. The ORPHEE and RHF reactors can not be operated with a LEU fuel which would be limited to 4.8 g U/cm{sup 3}. The OSIRIS reactor has already been converted to LEU. It will use U{sub 3}Si{sub 2} as soon as its present stock of UO{sub 2} fuel is used up, at the end of 1994. The decision to close down the SILOE reactor in the near future is not propitious for the start of a conversion process. The REX 2000 reactor, which is expected to be commissioned in 2005, will use LEU (except if the fast neutrons core option is selected). Concerning the end of the HEU fuel cycle, the best option is reprocessing followed by conversion of the reprocessed uranium to LEU.

  3. The French nuclear programme

    International Nuclear Information System (INIS)

    Bacher, Pierre

    1987-01-01

    France has a civil nuclear power generation programme second only to the USA with 49 nuclear units in operation and 13 under construction. The units in service are described. These include 33 PWR 900 MW and 9 PWR 1300 MW units. The electricity consumption and generation in France is illustrated. The absence of a powerful anti-nuclear lobby and two main technical options have contributed to the success of the French nuclear programme. These are the PWR design and the plant standardization policy which allows the setting up of an effective industrial complex (eg for analysis of operating conditions and of safety and reliability information). The programme and the reasons for its success are reviewed. Research programmes and future plans are also discussed. (UK)

  4. French courses for beginners

    CERN Multimedia

    Françoise Benz

    2006-01-01

    If you wish to participate in one of the following courses, please tell to your supervisor and apply electronically from the course description pages that can be found on the Web at: http://www.cern.ch/Training/ or fill in an 'application for training'form available from your Departmental Secretariat or from your DTO (Departmental Training Officer). Applications will be accepted in the order in which they are received. French courses for beginners (level 0) From 17 July to 31 August 2006. Mondays, Tuesdays, Wednesdays and Thursdays(8 hours a week / between 11.00 and 15.30) Duration: 56 hours Price: 728 CHF For registration and further information on the courses, please consult our Web pages: http://cern.ch/Training or contact Mrs. Benz: Tel. 73127.

  5. Status of French reactors

    International Nuclear Information System (INIS)

    Ballagny, A.

    1997-01-01

    The status of French reactors is reviewed. The ORPHEE and RHF reactors can not be operated with a LEU fuel which would be limited to 4.8 g U/cm 3 . The OSIRIS reactor has already been converted to LEU. It will use U 3 Si 2 as soon as its present stock of UO 2 fuel is used up, at the end of 1994. The decision to close down the SILOE reactor in the near future is not propitious for the start of a conversion process. The REX 2000 reactor, which is expected to be commissioned in 2005, will use LEU (except if the fast neutrons core option is selected). Concerning the end of the HEU fuel cycle, the best option is reprocessing followed by conversion of the reprocessed uranium to LEU

  6. Porous metal for orthopedics implants

    OpenAIRE

    Matassi, Fabrizio; Botti, Alessandra; Sirleo, Luigi; Carulli, Christian; Innocenti, Massimo

    2013-01-01

    Porous metal has been introduced to obtain biological fixation and improve longevity of orthopedic implants. The new generation of porous metal has intriguing characteristics that allows bone healing and high osteointegration of the metallic implants. This article gives an overview about biomaterials properties of the contemporary class of highly porous metals and about the clinical use in orthopaedic surgery.

  7. Hydration study of limestone blended cement in the presence of hazardous wastes containing Cr(VI)

    International Nuclear Information System (INIS)

    Trezza, M.A.; Ferraiuelo, M.F.

    2003-01-01

    Considering the increasing use of limestone cement manufacture, the present paper tends to characterize limestone behavior in the presence of Cr(VI). The research reported herein provides information regarding the effect of Cr(VI) from industrial wastes in the limestone cement hydration. The cementitious materials were ordinary Portland cement, as reference, and limestone blended cement. The hydration and physicomechanical properties of cementitious materials and the influence of chromium at an early age were studied with X-ray diffraction (XRD), infrared spectroscopy (FTIR), conductimetric and mechanical tests. Portland cement pastes with the addition of Cr(VI) were examined and leaching behavior with respect to water and acid solution were investigated. This study indicates that Cr(VI) modifies the rate and the components obtained during the cement hydration

  8. Limestones in Treinta y Tres district : Aerial photo of Jose P. Varela - Isla Patrulla

    International Nuclear Information System (INIS)

    Coronel, N.; Heinzen, W.

    1981-01-01

    This work brings information of fields and laboratory samples about the outcrop in Treinta y Tres district in the framework of limestones programme carried out jointly with I.G.U and BGR through the geological German mission

  9. Coated limestone as a filler for the production of PVC-products

    Directory of Open Access Journals (Sweden)

    Mihajlović Slavica

    2005-01-01

    Full Text Available The results of laboratory investigations of the possibility to obtain coated limestone for the production of PVC-products are presented in this paper. Limestone from the "Venčac" deposit (Aranđelovac, Serbia and Montenegro was used as the raw material. The investigations were carried out in two phases: obtaining the coated limestone and determination of the degree of coating. The results of the investigations showed that successful coating of the surface of the limestone particles with Ca-stearate (Ca-stearate content 3% was achieved in a vibro mill with rings and the obtained degree of coating was higher than 95%. The coating degree was determined in transmitted light by a polarization microscope applying the immersion method (water immersion.

  10. Systematic ichnology of microborings from the Cenozoic White Limestone Group, Jamaica, West Indies

    NARCIS (Netherlands)

    Blissett, D.J.; Pickerill, R.K.

    2007-01-01

    The Middle Eocene to Middle Miocene White Limestone Group of Jamaica contains a common and diverse, poorly to well-preserved microboring ichnofauna, namely Centrichnus eccentricus Bromley & Martinell, Curvichnus pediformis isp. nov., Dendrorete balani Tavernier, Campbell & Golubic, Dipatulichnus

  11. Improving DMS 9210 requirements for limestone rock asphalt : year one interim report.

    Science.gov (United States)

    2013-05-01

    Limestone Rock Asphalt (LRA) mixtures have been produced and placed for several decades using specification requirements currently listed under DMS 9210. Several Districts have had placement issues and premature failures at the beginning of 2010. The...

  12. Dolomitization in the diagenetic history of the Štramberg limestones

    Czech Academy of Sciences Publication Activity Database

    Lintnerová, O.; Knietl, M.; Reháková, D.; Skupien, P.; Vašíček, Zdeněk

    2008-01-01

    Roč. 34, 3/1 (2008), s. 191-192 ISSN 0138-0974 Institutional research plan: CEZ:AV0Z30860518 Keywords : Štramberk Limestone * dolomitization * dedolomitization Subject RIV: DB - Geology ; Mineralogy

  13. Electrokinetics in porous media

    NARCIS (Netherlands)

    Luong, D.T.

    2014-01-01

    This thesis presents the PhD research on electrokinetics in porous media. Electrokinetic phenomena are induced by the relative motion between a fluid and a solid surface and are directly related to the existence of an electric double layer between the fluid and the solid grain surface.

  14. Deterioration of limestone aggregate mortars by liquid sodium in fast breeder reactor environment

    Energy Technology Data Exchange (ETDEWEB)

    Mohammed Haneefa, K., E-mail: mhkolakkadan@gmail.com [Department of Civil Engineering, IIT Madras, Chennai (India); Santhanam, Manu [Department of Civil Engineering, IIT Madras, Chennai (India); Parida, F.C. [Radiological Safety Division, Indira Gandhi Centre for Atomic Research, Kalpakkam (India)

    2014-08-15

    Highlights: • Limestone mortars were exposed to liquid sodium exposure at 550 °C. • Micro-analytical techniques were used to characterize the exposed specimens. • The performance of limestone mortar was greatly influenced by w/c. • The fundamental degradation mechanisms of limestone mortars were identified. - Abstract: Hot liquid sodium at 550 °C can interact with concrete in the scenario of an accidental spillage of sodium in liquid metal cooled fast breeder reactors. To protect the structural concrete from thermo-chemical degradation, a sacrificial layer of limestone aggregate concrete is provided over it. This study investigates the fundamental mechanisms of thermo-chemical interaction between the hot liquid sodium and limestone mortars at 550 °C for a duration of 30 min in open air. The investigation involves four different types of cement with variation of water-to-cement ratios (w/c) from 0.4 to 0.6. Comprehensive analysis of experimental results reveals that the degree of damage experienced by limestone mortars displayed an upward trend with increase in w/c ratios for a given type of cement. Performance of fly ash based Portland pozzolana cement was superior to other types of cements for a w/c of 0.55. The fundamental degradation mechanisms of limestone mortars during hot liquid sodium interactions include alterations in cement paste phase, formation of sodium compounds from the interaction between solid phases of cement paste and aggregate, modifications of interfacial transition zone (ITZ), decomposition of CaCO{sub 3}, widening and etching of rhombohedral cleavages, and subsequent breaking through the weakest rhombohedral cleavage planes of calcite, staining, ferric oxidation in grain boundaries and disintegration of impurity minerals in limestone.

  15. Deterioration of limestone aggregate mortars by liquid sodium in fast breeder reactor environment

    International Nuclear Information System (INIS)

    Mohammed Haneefa, K.; Santhanam, Manu; Parida, F.C.

    2014-01-01

    Highlights: • Limestone mortars were exposed to liquid sodium exposure at 550 °C. • Micro-analytical techniques were used to characterize the exposed specimens. • The performance of limestone mortar was greatly influenced by w/c. • The fundamental degradation mechanisms of limestone mortars were identified. - Abstract: Hot liquid sodium at 550 °C can interact with concrete in the scenario of an accidental spillage of sodium in liquid metal cooled fast breeder reactors. To protect the structural concrete from thermo-chemical degradation, a sacrificial layer of limestone aggregate concrete is provided over it. This study investigates the fundamental mechanisms of thermo-chemical interaction between the hot liquid sodium and limestone mortars at 550 °C for a duration of 30 min in open air. The investigation involves four different types of cement with variation of water-to-cement ratios (w/c) from 0.4 to 0.6. Comprehensive analysis of experimental results reveals that the degree of damage experienced by limestone mortars displayed an upward trend with increase in w/c ratios for a given type of cement. Performance of fly ash based Portland pozzolana cement was superior to other types of cements for a w/c of 0.55. The fundamental degradation mechanisms of limestone mortars during hot liquid sodium interactions include alterations in cement paste phase, formation of sodium compounds from the interaction between solid phases of cement paste and aggregate, modifications of interfacial transition zone (ITZ), decomposition of CaCO 3 , widening and etching of rhombohedral cleavages, and subsequent breaking through the weakest rhombohedral cleavage planes of calcite, staining, ferric oxidation in grain boundaries and disintegration of impurity minerals in limestone

  16. Resedimented Limestones in Middle and Upper Jurassic Succession of the Slovenian Basin

    Directory of Open Access Journals (Sweden)

    Boštjan Rožič

    2006-12-01

    Full Text Available The Middle and Upper Jurassic succession of the Slovenian Basin is characterized by pelagic sedimentation of siliceous limestones and radiolarian cherts. In the southern and central part of the basin two packages of resedimented limestones are interbedded within pelagic sediments. The Lower resedimented limestones are lower-middle Bajocian to lower Callovian in age. In the southern part of the basin they form laterally discontinuous sequences composed of limestone breccias, calcarenites and micritic limestone and in the central part of the basin calcarenite intercalations within pelagic beds. They were transported by turbidity currents from highly productive ooidal shoals of the Dinaric Carbonate Platform. The Lower resedimented carbonates correlate with the lower three members of the Travnik Formation in the Bovec Trough and similarly developed but much thicker Vajont Formation in the Belluno Basin. The difference in thickness is interpreted as a consequence of shallow-water and longshore currents on the Dinaric Carbonate Platform that transported platform material towards southwest in the direction of the Belluno Basin. The Upper resedimented limestones are upper Kimmeridgian to lower Tithonian and occur within radiolarian cherts in the upper part of the succession as calcarenite beds that originated by turbidity currents. Onset of resedimentation coincides with the emersion-related demise of barrier reef and following deposition of micritic and rare oolitic limestones on the Dinaric Carbonate Platform. Approximatelly coeval resedimented limestones occur in the fourth member of the Travnik Formation in the Bovec Trough, but are not reported from the Ammonitico Rosso Superiore Formation in the Belluno Basin.

  17. Volume change of limestone and its effects on drying shrinkage of concrete

    OpenAIRE

    YAGI, Shogo; AQUINO, Carlos; INOUE, Masumi; OKAMOTO, Takahisa

    2010-01-01

    Recently, the cracks of concrete by drying shrinkage become one of the problems in the construction industry in Japan. The drying shrinkage decreases when the concrete is produced with limestone aggregate. However, it is not clear why the drying shrinkage is decreased. The purpose of this study is to clarify the relation between the drying shrinkage of concrete and the limestone aggregate. In this study, the experiments about the strength, elasticity and drying shrinkage of concrete and the p...

  18. CARBONIFEROUS CORALS AND CHAETETIDS FROM EXOTIC LIMESTONE BLOCK OF THE CRIMEA

    OpenAIRE

    OGAR, VICTOR; KLEVTSOVSKYI, ANDREY

    2015-01-01

    A chaetetid sponge and coral fauna from a Carboniferous exotic limestone block in the Lower Jurassic Esciorda olistostrome on the Bodrak River (Crimean Mountains) are described for the first time. The Bodrak exotic block is composed of massive limestone. It contains the chaetetid Chaetetes (Boswellia) sp., the tabulate coral Multithecopora sp., and poorly preserved rugose corals, including Dibunophyllum? sp., Cordibia? sp. and gen. et sp. indet. Only the fasciculate colonies of the rugose cor...

  19. Enhancement of direct sulfation of limestone by Na{sub 2}CO{sub 3} addition

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Chuanmin [School of Environmental Science and Engineering, North China Electric Power University, Baoding 071003, Hebei Province (China); Zhuang, Ye [Energy and Environmental Research Center, University of North Dakota, 15 North 23rd Street, Grand Forks, ND 58203 (United States); Wang, Chunbo [Department of Power engineering, North China Electric Power University, Baoding 071003, Hebei Province (China)

    2009-07-15

    For an oxy-fuel circulating fluidized bed combustion system, the limestone calcination is normally prevented due to excessive CO{sub 2} partial pressures and the limestone is subject to a direct sulfation reaction. The enhancement of the direct sulfation of limestone by Na{sub 2}CO{sub 3} was investigated under high CO{sub 2} partial pressure in a thermogravimetric apparatus (TGA) and scanning electron microscope (SEM) analysis method. A commercial limestone with a mean size of 18.8 {mu}m was used. Experimental results indicate that the incorporation of Na{sup +} ions in solid product CaSO{sub 4} lattice structures results in formation of more extrinsic point defects in the crystal lattices of CaSO{sub 4} and a significantly increased solid-state diffusivity/mobility in the solid product. So the direct sulfation of Na{sub 2}CO{sub 3}-doped limestone shows higher rate and higher degree of conversion in the later stage of sulfation, in comparison with the direct sulfation of original limestone. The reaction changes from diffusional control to chemical reaction control in the presence of Na{sub 2}CO{sub 3} because of the effect of foreign ions on accelerating the solid-state diffusion. (author)

  20. Enhancement of direct sulfation of limestone by Na{sub 2}CO{sub 3} addition

    Energy Technology Data Exchange (ETDEWEB)

    Chuanmin Chen; Ye Zhuang; Chunbo Wang [North China Electric Power University, Baoding (China). School of Environmental Science & Engineering

    2009-07-15

    For an oxy-fuel circulating fluidized bed combustion system, the limestone calcination is normally prevented due to excessive CO{sub 2} partial pressures and the limestone is subject to a direct sulfation reaction. The enhancement of the direct sulfation of limestone by Na{sub 2}CO{sub 3} was investigated under high CO{sub 2} partial pressure in a thermogravimetric apparatus (TGA) and scanning electron microscope (SEM) analysis method. A commercial limestone with a mean size of 18.8 {mu}m was used. Experimental results indicate that the incorporation of Na{sup +} ions in solid product CaSO{sub 4} lattice structures results in formation of more extrinsic point defects in the crystal lattices of CaSO{sub 4} and a significantly increased solid-state diffusivity/mobility in the solid product. So the direct sulfation of Na{sub 2}CO{sub 3}-doped limestone shows higher rate and higher degree of conversion in the later stage of sulfation, in comparison with the direct sulfation of original limestone. The reaction changes from diffusional control to chemical reaction control in the presence of Na{sub 2}CO{sub 3} because of the effect of foreign ions on accelerating the solid-state diffusion. 33 refs., 7 figs., 2 tabs.

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

    Energy Technology Data Exchange (ETDEWEB)

    Chen, C.M.; Zhao, C.S.; Liu, S.T.; Wang, C.B. [North China Electric Power University, Baoding (China)

    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.

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

    International Nuclear Information System (INIS)

    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

  3. Studies on limestone concrete as a low-activation structural material for nuclear power plants

    International Nuclear Information System (INIS)

    Uematsu, Mikio; Nagano, Hiroshi; Naito, Yasuhiro

    2000-01-01

    Because of low content of Li, Co and Eu, the target nuclides of activation reaction, limestone concrete is considered to be effective in reducing the decommissioning cost of nuclear plants. Induced activity calculation and structural strength test were performed for limestone concrete and the results were compared with the data obtained for sandstone concrete, which is generally used in nuclear plants. Minor elements, which are important from the viewpoint of activation, were measured with elementary analysis for limestone samples from three different quarries in Japan. Induced activity in biological shield walls (BSW) of Boiling Water Reactor (BWR) plants was calculated with the isotope generation code ORIGEN-79 using neutron flux data obtained with the one-dimensional Sn transport code ANISN and MGCL 137-group activation cross section library based on JENDL-3. Estimated total radioactivity accumulated in limestone concrete BSW was 5 times lower than that in the sandstone concrete BSW. Structural strength were compared between limestone concrete and sandstone concrete, and limestone concrete was found to have enough compressive strength and tensile strength. (author)

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

    Science.gov (United States)

    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.

  5. Influence of limestone waste as partial replacement material for sand and marble powder in concrete properties

    Directory of Open Access Journals (Sweden)

    Omar M. Omar

    2012-12-01

    Full Text Available Green concrete are generally composed of recycling materials as hundred or partial percent substitutes for aggregate, cement, and admixture in concrete. Limestone waste is obtained as a by-product during the production of aggregates through the crushing process of rocks in rubble crusher units. Using quarry waste as a substitute of sand in construction materials would resolve the environmental problems caused by the large-scale depletion of the natural sources of river and mining sands. This paper reports the experimental study undertaken to investigate the influence of partial replacement of sand with limestone waste (LSW, with marble powder (M.P as an additive on the concrete properties. The replacement proportion of sand with limestone waste, 25%, 50%, and 75% were practiced in the concrete mixes except in the concrete mix. Besides, proportions of 5%, 10% and 15% marble powder were practiced in the concrete mixes. The effects of limestone waste as fine aggregate on several fresh and hardened properties of the concretes were investigated. The investigation included testing of compressive strength, indirect tensile strength, flexural strength, modulus of elasticity, and permeability. It was found that limestone waste as fine aggregate enhanced the slump test of the fresh concretes. But the unit weight concretes were not affected. However, the good performance was observed when limestone waste as fine aggregate was used in presence of marble powder.

  6. Environmentally acceptable effect of hydrogen peroxide on cave 'lamp-flora', calcite speleothems and limestones

    International Nuclear Information System (INIS)

    Faimon, Jiri; Stelcl, Jindrich; Kubesova, Svatava; Zimak, Jiri

    2003-01-01

    Hydrogen peroxide plus limestone fragments allows removal of organisms without corrosion of limestone and speleothem. - 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 Katerinska 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 3.77x10 -3 and 1.81x10 -3 mol m -2 h -1 , respectively. In the 15% peroxide solution, the limestone and speleothem dissolution rates were one order of magnitude higher, 2.00x10 -2 and 2.21x10 -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

  7. Practising French grammar a workbook

    CERN Document Server

    Dr Roger Hawkins; Towell, Richard

    2015-01-01

    This new edition of Practising French Grammar offers a set of varied and accessible exercises for developing a practical awareness of French as it is spoken and written today. The lively examples and authentic texts and cartoons have been updated to reflect current usage. A new companion website provides a wealth of additional interactive exercises to help consolidate challenging grammar points. Practising French Grammar provides concise summaries of key grammatical points at the beginning of each exercise, as well as model answers to the exercises and translations of difficult words, making i

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

    Science.gov (United States)

    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.

  9. French Literature Abroad: Towards an Alternative History of French Literature

    Directory of Open Access Journals (Sweden)

    Simon Gaunt

    2015-07-01

    Full Text Available What would a history of medieval literature in French that is not focused on France and Paris look like? Taking as its starting point the key role played in the development of textual culture in French by geographical regions that are either at the periphery of French-speaking areas, or alternatively completely outside them, this article offers three case studies: first of a text composed in mid-twelfth century England; then of one from early thirteenth-century Flanders; and finally from late thirteenth-century Italy. What difference does it make if we do not read these texts, and the language in which they are written, in relation to French norms, but rather look at their cultural significance both at their point of production, and then in transmission? A picture emerges of a literary culture in French that is mobile and cosmopolitan, one that cannot be tied to the teleology of an emerging national identity, and one that is a bricolage of a range of influences that are moving towards France as well as being exported from it. French itself functions as a supralocal written language (even when it has specific local features and therefore may function more like Latin than a local vernacular.

  10. French LMFBR's control rods experience and development

    International Nuclear Information System (INIS)

    Arnaud, G.; Guigon, A.; Verset, L.

    1983-06-01

    Since the last ten years, the French program has been, first of all, directed to the setting up, and then the development of, at once, the Phenix control rods, and next, the Super-Phenix ones. The vented pin design, with porous plug and sodium bonding, which allows the choices of large diameters, has been taken, since the Rapsodie experience was decisive. The absorber material is sintered, 10 B enriched, boron carbide. The can is made of 316 type stainless steel, stabilised, or not, with titanium. The experience gained in Phenix up to now is important, and deals with about six loads of control rods. Results confirm the validity of the design of the absorber pins. Some difficulties has been encountered for the guiding devices, due to the swelling of the steel. They have required design and material improvements. Such difficulties are discarded by a new design of the bearing, for the Super-Phenix control rods. The other parts of these rods, from the Primary Shut-Down System, are strictly derived from Phenix. The design of the rods from the Secondary Shut-Down System is rather different, but it's not the case for the design of the absorber pins: in many a way, they are derived from Phenix pins and from Rapsodie control rods. Both types of rods irradiation tests are in progress in Phenix [fr

  11. English and French courses

    CERN Multimedia

    2014-01-01

    If one of your New Year’s resolutions is to learn a language, there is no excuse anymore!   You can attend one of our English or French courses and you can practise the language with a tandem partner! Cours d’anglais général et professionnel La prochaine session se déroulera du 3 mars au 27 juin 2014. Ces cours s’adressent à toute personne travaillant au CERN ainsi qu’à leur conjoint. Pour vous inscrire et voir tout le détail des cours proposés, consultez nos pages web : http://cern.ch/Training. Oral Expression The next session will take place from 3 March to 27 June 2014. This course is intended for people with a good knowledge of English who want to enhance their speaking skills. There will be an average of 8 participants in a class. Speaking activities will include discussions, meeting simulations, role-plays etc. depending on the needs of the students. Writing Profe...

  12. General and professionnal French courses

    CERN Document Server

    2013-01-01

    The next session will take place from 27 January to 4 April 2014. These courses are open to everyone working on the CERN site and to their spouses.   Oral Expression This course is aimed at students with a good knowledge of French who want to enhance their oral communication skills. Activities will include discussions, meeting simulations, role-plays, etc. The next session will take place from 27 January to 4 April 2014. Writing professional documents in French These courses are designed for non-French speakers with a very good standard of spoken French. The next session will take place from 27 January to 4 April 2014. For registration and further information on the courses, please consult our web site or contact Kerstin Fuhrmeister (70896 - language.training@cern.ch).

  13. General and professionnal French courses

    CERN Multimedia

    2013-01-01

    The next session will take place from 27 January to 4 April 2014. These courses are open to everyone working on the CERN site and to their spouses.   Oral Expression This course is aimed at students with a good knowledge of French who want to enhance their speaking skills. Speaking activities will include discussions, meeting simulations, role-plays etc. The next session will take place from 27 January to 4 April 2014. Writing professional documents in French These courses are designed for non-French speakers with a very good standard of spoken French. The next session will take place from 27 January to 4 April 2014. For registration and further information on the courses, please consult our web site or contact Kerstin Fuhrmeister (70896 - language.training@cern.ch).

  14. French switch off in protest

    CERN Document Server

    McCabe, H

    1999-01-01

    French scientists have refused to restart two synchrotron machines after the summer vacation. They are protesting at the government decision to give money to the British synchrotron project Diamond, so ending hopes of the construction of the proposed

  15. Reshuffle lifts French synchrotron hopes

    CERN Multimedia

    McCabe, H

    2000-01-01

    The sacking of Claude Allegre as research minister has raised doubts over the level of France's promised participation in the construction of Diamond but reawakened French hopes that the synchrotron Soleil may now be built (1 page).

  16. 21 CFR 169.115 - French dressing.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false French dressing. 169.115 Section 169.115 Food and... § 169.115 French dressing. (a) Description. French dressing is the separable liquid food or the..., lecithin, or polyglycerol esters of fatty acids. (d) Nomenclature. The name of the food is “French dressing...

  17. Teaching for Content: Greek Mythology in French.

    Science.gov (United States)

    Giauque, Gerald S.

    An intermediate-level university French course in Greek mythology was developed to (1) improve student skills in reading, writing, speaking, and comprehending French, (2) familiarize students with Greek mythology, and (3) prepare students to deal better with allusions to Greek mythology in French literature. The texts used are a French translation…

  18. 7 CFR 993.7 - French prunes.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false French prunes. 993.7 Section 993.7 Agriculture... Order Regulating Handling Definitions § 993.7 French prunes. French prunes means: (a) Prunes produced from plums of the following varieties of plums: French (Prune d'Agen, Petite Prune d'Agen), Coates (Cox...

  19. English Grammar for Students of French.

    Science.gov (United States)

    Morton, Jacqueline

    This grammar is a self-study manual intended to aid native speakers of English who are beginning the study of French. It is designed to supplement the French textbook, not to replace it. The common grammatical terms that are necessary for learning to speak and write French are explained in English and illustrated by examples in both French and…

  20. Experimental study and mechanism analysis of modified limestone by red mud for improving desulfurization

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Hongtao; Han, Kuihua; Niu, Shengli; Lu, Chunmei; Liu, Mengqi; Li, Hui [Shandong Univ., Jinan (China). School of Energy and Power Engineering

    2013-07-01

    Red mud is a type of solid waste generated during alumina production from bauxite, and how to dispose and utilize red mud in a large scale is yet a question with no satisfied answer. This paper attempts to use red mud as a kind of additive to modify the limestone. The enhancement of the sulfation reaction of limestone by red mud (two kinds of Bayer process red mud and one kind of sintering process red mud) are studied by a tube furnace reactor. The calcination and sulfation process and kinetics are investigated in a thermogravimetric (TG) analyzer. The results show that red mud can effectively improve the desulfurization performance of limestone in the whole temperature range (1,073-1,373K). Sulfur capacity of limestone (means quality of SO{sub 2} which can be retained by 100mg of limestone) can be increased by 25.73, 7.17 and 15.31% while the utilization of calcium can be increased from 39.68 to 64.13%, 60.61 and 61.16% after modified by three kinds of red mud under calcium/metallic element (metallic element described here means all metallic elements which can play a catalytic effect on the sulfation process, including the Na, K, Fe, Ti) ratio being 15, at the temperature of 1,173K. The structure of limestone modified by red mud is interlaced and tridimensional which is conducive to the sulfation reaction. The phase composition analysis measured by XRD of modified limestone sulfated at high temperature shows that there are correspondingly more sulphates for silicate and aluminate complexes of calcium existing in the products. Temperature, calcium/metallic element ratio and particle diameter are important factors as for the sulfation reaction. The optimum results can be obtained as calcium/metallic element ratio being 15. Calcination characteristic of limestone modified by red mud shows a migration to lower temperature direction. The enhancement of sulfation by doping red mud is more pronounced once the product layer has been formed and consequently the promoting

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

    Science.gov (United States)

    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

  2. French days on stable isotopes

    International Nuclear Information System (INIS)

    2000-01-01

    These first French days on stable isotopes took place in parallel with the 1. French days of environmental chemistry. Both conferences had common plenary sessions. The conference covers all aspects of the use of stable isotopes in the following domains: medicine, biology, environment, tracer techniques, agronomy, food industry, geology, petroleum geochemistry, cosmo-geochemistry, archaeology, bio-geochemistry, hydrology, climatology, nuclear and particle physics, astrophysics, isotope separations etc.. Abstracts available on CD-Rom only. (J.S.)

  3. French lessons in nuclear power

    International Nuclear Information System (INIS)

    Valenti, M.

    1991-01-01

    In stark contrast to the American atomic power experience is that of the French. Even the disaster at Chernobyl in 1986, which chilled nuclear programs throughout Western Europe, did not slow the pace of the nuclear program of the state-owned Electricite de France (EDF), based in Paris. Another five units are under construction and are scheduled to be connected to the French national power grid before the end of 1993. In 1989, the EDF's 58 nuclear reactors supplied 73 percent of French electrical needs, a higher percentage than any other country. In the United States, for example, only about 18 percent of electrical power is derived from the atom. Underpinning the success of nuclear energy in France is its use of standardized plant design and technology. This has been an imperative for the French nuclear power industry since 1974, when an intensive program of nuclear power plant construction began. It was then, in the aftermath of the first oil embargo, that the French government decided to reduce its dependence on imported oil by substituting atomic power sources for hydrocarbons. Other pillars supporting French nuclear success include retrofitting older plants with technological or design advances, intensive training of personnel, using robotic and computer aids to reduce downtime, controlling the entire nuclear fuel cycle, and maintaining a comprehensive public information effort about the nuclear program

  4. Anglicism in the French language

    Directory of Open Access Journals (Sweden)

    Firoozeh Asghari

    2014-09-01

    Full Text Available There is no question nowadays as to the international and powerful status of English at a global scale and, consequently, as to its presence in non-English speaking countries at different levels.  It is the languages which have mostly influenced French after the Two World War. So that now Anglicism exists in all levels of French. In this paper, besides the phenomenon of Anglicism, we will mainly focus on the reasons of increasing French interest in using of this phenomenon and also on the reactions taken against it in France. The method used in this research is descriptive – analytical.   The Result of this study shows that there is no purely linguistic reason for “Anglicism” in a country like France. In fact this paper remarks that the strong impact of English on French rather than being influenced by linguistic reasons is influenced by the cultural & social reasons. Additionally, the finding shows that the French especially the youth like using English for several reasons which include “prestige”, “snobbery” and “superiority”. Amongst the mentioned reasons in this paper, what caused the French to worry about the spread of Anglicism is due to fear of the American cultural influence, what is changing in the American cultural hegemony.

  5. Graded/Gradient Porous Biomaterials

    Directory of Open Access Journals (Sweden)

    Xigeng Miao

    2009-12-01

    Full Text Available Biomaterials include bioceramics, biometals, biopolymers and biocomposites and they play important roles in the replacement and regeneration of human tissues. However, dense bioceramics and dense biometals pose the problem of stress shielding due to their high Young’s moduli compared to those of bones. On the other hand, porous biomaterials exhibit the potential of bone ingrowth, which will depend on porous parameters such as pore size, pore interconnectivity, and porosity. Unfortunately, a highly porous biomaterial results in poor mechanical properties. To optimise the mechanical and the biological properties, porous biomaterials with graded/gradient porosity, pores size, and/or composition have been developed. Graded/gradient porous biomaterials have many advantages over graded/gradient dense biomaterials and uniform or homogenous porous biomaterials. The internal pore surfaces of graded/gradient porous biomaterials can be modified with organic, inorganic, or biological coatings and the internal pores themselves can also be filled with biocompatible and biodegradable materials or living cells. However, graded/gradient porous biomaterials are generally more difficult to fabricate than uniform or homogenous porous biomaterials. With the development of cost-effective processing techniques, graded/gradient porous biomaterials can find wide applications in bone defect filling, implant fixation, bone replacement, drug delivery, and tissue engineering.

  6. Convection in Porous Media

    CERN Document Server

    Nield, Donald A

    2013-01-01

    Convection in Porous Media, 4th Edition, provides a user-friendly introduction to the subject, covering a wide range of topics, such as fibrous insulation, geological strata, and catalytic reactors. The presentation is self-contained, requiring only routine mathematics and the basic elements of fluid mechanics and heat transfer. The book will be of use not only to researchers and practicing engineers as a review and reference, but also to graduate students and others entering the field. The new edition features approximately 1,750 new references and covers current research in nanofluids, cellular porous materials, strong heterogeneity, pulsating flow, and more. Recognized as the standard reference in the field Includes a comprehensive, 250-page reference list Cited over 2300 times to date in its various editions Serves as an introduction for those entering the field and as a comprehensive reference for experienced researchers Features new sections on nanofluids, carbon dioxide sequestration, and applications...

  7. Porous electrode preparation method

    Science.gov (United States)

    Arons, R.M.; Dusek, J.T.

    1983-10-18

    A porous sintered plaque is provided with a bimodal porosity that is especially well suited for use as an electrode within a molten carbonate fuel cell. The coarse porosity is sufficient for admitting gases into contact with the reaction surfaces while the fine porosity is wetted with and retains molten electrolyte on the reaction sites. The electrode structure is prepared by providing a very fine powder of such as nickel oxide and blending the powder with a suitable decomposable binder to form a solid mass. The mass is comminuted into agglomerate size particles substantially larger than the fine oxide particles and formed into a cohesive compact for subsequent sintering. Sintering is carried out at sufficient conditions to bind the agglomerates together into a porous structure having both coarse and fine porosity. Where lithiated nickel oxide cathodes are prepared, the sintering conditions can be moderate enough to retain substantial quantities of lithium within the electrode for adequate conductivity. 2 figs.

  8. Studies on the preparation of value-added products for limestone

    Energy Technology Data Exchange (ETDEWEB)

    Chae, Young Bae; Jeong, Soo Bok; Ko, Won Sik; Park, Je Shin; Oh, Jung Whan [Korea Institute of Geology Mining and Materials, Taejon (Korea, Republic of)

    1997-12-01

    Most of limestone in our country was consumed by the cement and iron/steel making industries and the amount of that was up to 72 million ton in 1996. Recently, importation of high grade limestone that have properties of high whiteness and grade are increased with diversification of chemical products and powder as various qualified filler, because high grade limestone are limited and of few deposit in our country. Therefore, the purpose of this study has investigated to raise to high grade by economical processes with low grade of domestic limestone. In this year, first of all, we investigated the status of application utilize and related industries with the domestic limestone, and then being consideration with condition selected the adequate sample from Andong, Jungsun and Kumsan area. Magnetic materials were involved in impurities of sample, so magnetic separation method was applied in elimination of the ferro-magnetic materials and para-magnetic materials, such as chlorite, muscovite, quartz, dolomite, magnetite, feldspar and so on. The limestone sample has many kinds of impurity. Investigation of flotation was undertaken to eliminate impurities from limestone crude ore and the tests were performed to get a optimum condition adding oleic acid as a promoter, sodium silicate and sodium carbonate as a conditioning agents and MIBC as a frother, while to float the sulfide minerals added amyl xanthate as a promoter, and sulfuric acid as a pH regulator. And most of the impurities involving in flotation sink contained such as quartz, chlorite, muscovite, feldspar, dolomite and so on. Selective crushing and classification methods were performed to eliminate impurities depends on the mineral properties and should be the selective crushing methods are very useful at the manufacturing factory of heavy calcium carbonate with the dry milling system. (author). 36 refs., 46 tabs., 33 figs.

  9. Porous germanium multilayers

    Energy Technology Data Exchange (ETDEWEB)

    Garralaga Rojas, Enrique; Hensen, Jan; Brendel, Rolf [Institut fuer Solarenergieforschung Hameln (ISFH), Emmerthal (Germany); Carstensen, Juergen; Foell, Helmut [Chair for General Materials Science, Faculty of Engineering, Christian-Albrechts-University of Kiel (Germany)

    2011-06-15

    We present the reproducible fabrication of porous germanium (PGe) single- and multilayers. Mesoporous layers form on heavily doped 4'' p-type Ge wafers by electrochemical etching in highly concentrated HF-based electrolytes with concentrations in a range of 30-50 wt.%. Direct PGe formation is accompanied by a constant dissolution of the already-formed porous layer at the electrolyte/PGe interface, hence yielding a thinner substrate after etching. This effect inhibits multilayer formation as the starting layer is etched while forming the second layer. We avoid dissolution of the porous layer by alternating the etching bias from anodic to cathodic. PGe formation occurs during anodic etching whereas the cathodic step passivates pore walls with H-atoms and avoids electropolishing. The passivation lasts a limited time depending on the etching current density and electrolyte concentration, necessitating a repetition of the cathodic step at suitable intervals. With optimized alternating bias mesoporous multilayer production is possible. We control the porosity of each single layer by varying the etching current density and the electrolyte (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  10. Pollutant transport in clayey sands: reactive flows in saturated porous media and unsaturated flows

    International Nuclear Information System (INIS)

    Cadalen, Sebastien

    2008-01-01

    In the context of nuclear risk control associated to nuclear waste storage, the french nuclear agency plays an increasing role in terms of research and development in the area of subsurface contamination. This study focuses on an homogeneous porous media constituted of Fontainebleau sand and clay grains (illite) presenting sorption capacities. The modeling of the complex geometry and physical phenomena at different scales enables us to describe the average transport at Darcy's scale. The two main axes developed are the impact of an heterogeneous sorption on transport phenomena and the dispersivity of an unsaturated porous media. (author) [fr

  11. Ecological Study in Two Quarried Limestone Karst Hills in Bogor West Java: Vegetation Structure and Floristic Composition

    OpenAIRE

    SATYANTI, ANNISA; CANDRA KUSUMA, YAYAN WAHYU

    2010-01-01

    Many species extinctions have probably gone unnoticed on limestone that was destroyed before they could be sampled. Unless biodiversity surveys are intensified, the true magnitude of extinctions will never be ascertained. The objectives of this study were to determine tree species composition of limestone hills in Nyungcung and Ciampea; to determine quantitatively the dominant and less dominant species and to quantify floristic structure of the two limestone hills. Value of richness (Menhinic...

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

    Science.gov (United States)

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

    2016-04-01

    The limestone known as Drenov Grič black limestone is considered one of the most beautiful Slovenian natural stones due to its homogenous black colour interwoven with white veins. Over the centuries it has been exploited from three major quarries west of Ljubljana, with the main quarry at Drenov Grič playing the primary role in supplying building material for the central parts of Slovenia. All the quarries are currently not active. In the area of Drenov grič, one locality of black limestone is protected - Kuclerjev kamnolom quarry. It has the status of 'valuable natural feature of national importance' and is protected as a natural monument. This well-stratified micritic limestone of Triassic (Carnian) age occurs in 10-80 cm thick beds, with thin marl interlayers. The stone contains abundant fossil bivalves and ostracods. Apart from calcite as the main component, dolomite, quartz, illite/muscovite and pyrite are also present. The limestone is relatively rich in carbonaceous and bituminous organic matter, which is responsible for the black colour of the stone. This component does not have any adverse effect on mechanical and physical characteristics. As the lime¬stone is dense, thus facilitating a good polish, it has been commercially considered as marble. The stone has been widely used in Slovenian monuments, not only in Ljubljana but also in other regions of Slovenia. Many inner and outdoor architectural elements were made of this limestone, particularly in the baroque period, which was known for the extensive use of black limestones also in other European countries. The most significant use of this limestone has been recorded in sculptured portals and altars. Some of the important buildings decorated utilising this stone, are the Ljubljana Cathedral, the St. James's Parish Church, and the Franciscan Church of the Annunciation, all of which are located in Ljubljana, some of them having been declared as cultural monuments of local or national importance. When

  13. Steam Cured Self-Consolidating Concrete and the Effects of Limestone Filler

    Science.gov (United States)

    Aqel, Mohammad A.

    The purpose of this thesis is to determine the effect and the mechanisms associated with replacing 15% of the cement by limestone filler on the mechanical properties and durability performance of self-consolidating concrete designed and cured for precast/prestressed applications. This study investigates the role of limestone filler on the hydration kinetics, mechanical properties (12 hours to 300 days), microstructural and durability performance (rapid chloride permeability, linear shrinkage, sulfate resistance, freeze-thaw resistance and salt scaling resistance) of various self-consolidating concrete mix designs containing 5% silica fume and steam cured at a maximum holding temperature of 55°C. This research also examines the resistance to delayed ettringite formation when the concrete is steam cured at 70°C and 82°C and its secondary consequences on the freeze-thaw resistance. The effect of several experimental variables related to the concrete mix design and also the curing conditions are examined, namely: limestone filler fineness, limestone filler content, cement type, steam curing duration and steam curing temperature. In general, the results reveal that self-consolidating concrete containing 15% limestone filler, steam cured at 55°C, 70°C and 82°C, exhibited similar or superior mechanical and transport properties as well as long term durability performance compared to similar concrete without limestone filler. When the concrete is steam cured at 55°C, the chemical reactivity of limestone filler has an important role in enhancing the mechanical properties at 16 hours (compared to the concrete without limestone filler) and compensating for the dilution effect at 28 days. Although, at 300 days, the expansion of all concrete mixes are below 0.05%, the corresponding freeze-thaw durability factors vary widely and are controlled by the steam curing temperature and the chemical composition of the cement. Overall, the material properties indicate that the use

  14. Factors involved in the selection of limestone reagents for use in wet FGD systems

    International Nuclear Information System (INIS)

    Jarvis, J.B.; Roothaan, E.S.; Meserole, F.B.; Owens, D.R.

    1992-01-01

    With recent activity in the design and construction of retrofit flue gas desulfurization (FGD) systems, many utilities are faced with the task of selecting limestones which will allow FGD systems to function as designed, and at the same time, provide cost-effective operation. The Electric Power Research Institute (EPRI) has sponsored research to identify factors which should be considered in the reagent selection process. A set of capabilities has been developed which is currently being employed to assist six utilities in selecting cost-effective reagent sources. The major elements in the selection package consist of an analytical characterization of candidate limestones; grindability, reactivity, and magnesium availability testing; and performance modeling utilizing EPRI's FGD PRocess Integration and Simulation Model (FGDPRISM). The results from these measurements are used to perform a site-specific economic analysis which can be used to rank the candidate limestones and quantify the impact of various limestone properties on plant operating costs. This paper includes a description of each element in the selection package along with a review of current research activities aimed at improving predictions of limestone reactivity and magnesium availability. An example is presented which illustrates how reactivity and magnesium availability affect both the performance of an FGD system and plant operating costs

  15. Ruminal degradation of dry matter and neutral detergent fiber of banana peel treated with limestone

    Directory of Open Access Journals (Sweden)

    Flávio Pinto Monção

    2016-02-01

    Full Text Available This study aimed to evaluate the kinetics of dry matter degradation and neutral detergent fiber of banana peel treated with limestone. The banana peel has been acquired from a candy manufacturer that after washing with chlorinated water to 1% and pulp removal was discarded. The banana peel in nature was treated with 1, 2, 3 and 4% of limestone in the natural matter, homogenized and pre-dried in the sun for 120 hours. The experiment was conducted in a completely randomized experimental design, with five treatments (0 (control, 1, 2, 3 and 4% inclusion of limestone with 3 repetitions. The dry matter potential degradability, showed no difference (P>0.05 in the levels compared to the control with an average of 67.58%. The insoluble degradation fraction rate of dry matter and the fiber fraction did not differ (P> 0.05 between levels and control. In relation to effective degradability of neutral detergent fiber, there was an increase of 3.47% for each percentage unit increased limestone. In relation to the ruminal degradation parameters of dry matter and neutral detergent fiber is not recommended the utilization of limestone as an additive in the treatment of banana peel.

  16. Gamma radiation influence on Cladonia substellata (lichen) and its effects on limestone rocks

    International Nuclear Information System (INIS)

    Silva, Helena P. de B.; Colaco, Waldeciro; Pereira, Eugenia C.; Silva, Nicacio H. da

    2009-01-01

    The lichens play an important role in decomposition of the rocky substrate, through the chemical weathering of their substances. This work aimed to determine the influence of gamma Ray on usnic acid production of Cladonia substellata and the influence of chelates formation in limestone rocks. Samples with 2.5 g of C. substellata were packed on paper envelopes for irradiation submission to gamma on a Co-60 source. They received 10 different doses: 5, 7, 10, 15, 20, 30, 40, 50, 60 and 80 Gy. Lichen irradiation was conducted on the gamma irradiator (Co-60), and packed over powdered limestone. Lichen samples were analyzed by High Performance Liquid Chromatography (HPLC) and rocky samples by X-Ray Diffractometry. The X-ray diffractogram obtained from the analysis of limestone not subjected to the action of lichen - control sample was compared with limestone subjected to C. substellata irradiated at doses 10, 30 and 80Gy. Increased production of the usnic acid and changes on the rocky samples were noted. We realized that C. substellata increments the usnic acid biosynthesis as the gamma radiation dose is increased, but there is a limit to it. The chelating effect of the usnic acid on limestone was proportional to the produced amount of the substance, which could be extrapolated to natural conditions, where excessive radiation may influence pedogenesis and ecological succession. (author)

  17. Microfacies and Diagenetic Fabric of the Lockhart Limestone, Kotal Pass Section, Northeast of Kohat, Pakistan

    Directory of Open Access Journals (Sweden)

    Muhammad Waseem Khan

    2016-06-01

    Full Text Available The present study is intended to describe the carbonate microfacies of the Paleocene Lockhart Limestone in area northeast of the Kohat City. The analyzed limestone in the area is 65m thick and predominantly medium to thick bedded, nodular to brecciated and richly fossiliferous. Thin interbeds of marl are observed in the main lithological unit. The lower contact of the Lockhart Limestone is faulted with the Samana Suk Formation of the Jurassic age while conformably overlain by the Patala Formation of Paleocene to Eocene age. The major lithological unit is comprised of predominant assemblage of larger benthic and smaller planktonic foraminifers with accretion of ostracods, dasycladacean algae, echinoderms, gastropods and corals. On the basis of field and laboratory observations, two distinct types of microfacies have been identified as i Dasyclad-Miliolid Foram Wacke-Packstone microfacies of the inner shelf, sub tidal lagoon, ii Larger Foram Packstone microfacies of the middle shelf. The Limestone represents a carbonate cyclic sequence marked by three, transgressive, deepening up cycles representing a gradual sea level rise compensated by vertical accumulation of microfacies. The commencement of each cycle is clearly marked by the input of land-derived siliciclastic sediments and near shore restricted marine faunal/floral assemblage in the inner shelf microfacies gradually thinning up section where the microfacies become deeper offshore. The diagenetic modifications are observed in the shape of compactional framework, dolomitization, aragonite to calcite alteration and spar filled fractures in the main lithological unit of the Lockhart Limestone.

  18. Reclamation of acidic colliery spoil. III. Problems associated with the use of high rates of limestone

    Energy Technology Data Exchange (ETDEWEB)

    Costigan, P A [Univ. of Liverpool, England; Bradshaw, A D; Gemmell, R P

    1982-04-01

    Growth of Trifolium repens in acidic colliery spoil was suppressed by more than 90% when agricultural ground calcitic limestone was applied at above 5 t ha/sup -1/ whereas Lolium perenne was unaffected at rates up to 100 t ha/sup -1/. The inhibitory effect of ground limestone on T. repens was reduced by high phosphorus fertilization and disappeared within 34 weeks of treatment.There was some evidence that high liming caused an imbalance of the Ca/Mg ratio in freshly limed spoil, contribution to growth inhibition. Growth of L. perene was improved and the inhibitory effect on T. repens was alleviated by substituting magnesian limestone (dolomite) for calcitic limestone. Phosphate adsorption of spoil was similar after low and very high limestone applications but increased by 100% after liming at 25 t ha/sup -1/ to pH 5.1.It is suggested that phosphate adsorption at pH 5.1 is caused by freshly precipitated amorphous aluminium hydroxide. The practical implications of the results are discussed.

  19. Actinobacterial diversity in limestone deposit sites in Hundung, Manipur (India and their antimicrobial activities

    Directory of Open Access Journals (Sweden)

    Salam eNimaichand

    2015-05-01

    Full Text Available 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.

  20. Porous ceramics out of oxides

    International Nuclear Information System (INIS)

    Bakunov, V.S.; Balkevich, V.L.; Vlasov, A.S.; Guzman, I.Ya.; Lukin, E.S.; Poluboyarinov, D.N.; Poliskij, R.Ya.

    1977-01-01

    A review is made of manufacturing procedures and properties of oxide ceramics intended for high-temperature thermal insulation and thermal protection applications. Presented are structural characteristics of porous oxide refractories and their properties. Strength and thermal conductivity was shown to depend upon porosity. Described is a procedure for manufacturing porous ceramic materials from aluminium oxide, zirconium dioxide, magnesium oxide, beryllium oxide. The thermal resistance of porous ceramics from BeO is considerably greater than that of other high-refractoriness oxides. Listed are areas of application for porous materials based on oxides

  1. Selective formation of porous silicon

    Science.gov (United States)

    Fathauer, Robert W. (Inventor); Jones, Eric W. (Inventor)

    1993-01-01

    A pattern of porous silicon is produced in the surface of a silicon substrate by forming a pattern of crystal defects in said surface, preferably by applying an ion milling beam through openings in a photoresist layer to the surface, and then exposing said surface to a stain etchant, such as HF:HNO3:H2O. The defected crystal will preferentially etch to form a pattern of porous silicon. When the amorphous content of the porous silicon exceeds 70 percent, the porous silicon pattern emits visible light at room temperature.

  2. Impacts of Limestone Multi-particle Size on Production Performance, Egg Shell Quality, and Egg Quality in Laying Hens

    Directory of Open Access Journals (Sweden)

    X. Y. Guo

    2012-06-01

    Full Text Available This experiment was conducted to evaluate the effects of single or multi-particle size limestone on the egg shell quality, egg production, egg quality and feed intake in laying hens. A total of 280 laying hens (ISA brown were used in this 10-wk trial. Laying hens were randomly assigned to 4 treatments with 14 replications per treatment and 5 adjacent cages as a replication (hens were caged individually. The experimental treatments were: i L, basal diet+10% large particle limestone; ii LS1, basal diet+8% large particle limestone+2% small particle limestone; iii LS2, basal diet+6% large particle limestone+4% small particle limestone; iv S, basal diet+10% small particle limestone. The egg production was unaffected by dietary treatments. The egg weight in S treatment was lighter than other treatments (p<0.05. The egg specific gravity in S treatment was lower than other treatments (p<0.05. The eggshell strength and eggshell thickness in S treatment were decreased when compared with other dietary treatments (p<0.05. The laying hens in LS1 and LS2 treatment had a higher average feed intake than the other two treatments (p<0.05. Collectively, the dietary multi-particle size limestone supplementation could be as efficient as large particle size limestone.

  3. Porosity development in the Copper Ridge Dolomite and Maynardville Limestone, Bear Creek Valley and Chestnut Ridge, Tennessee

    International Nuclear Information System (INIS)

    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

  4. Neutron radiography for the characterization of porous structure in degraded building stones

    International Nuclear Information System (INIS)

    Barone, G; Mazzoleni, P; Raneri, S; Crupi, V; Longo, F; Majolino, D; Venuti, V; Teixeira, J

    2014-01-01

    As it is well known, the porous structure of stones can change due to different degradation processes that modify the characteristics of freshly quarried blocks. Their knowledge is fundamental for predicting the behavior of stones and the efficacy of conservative treatments. In this context, neutron radiography is a useful tool not only to visualize the structure of porous materials, but also to evaluate the degree of degradation and surface modifications resulting from weathering processes. Furthermore, since thermal neutrons suffer a strong attenuation by hydrogen, this technique is effective in order to investigate the amount of absorbed water in building materials. In the present work, we report a neutron radiography investigation of limestones cropping out in the South-Eastern Sicily and widely used as building stones in Baroque monuments of the Noto Valley. The analyzed samples have been submitted to cyclic salt crystallization that simulate degradation processes acting in exposed stones of buildings. The obtained results demonstrate the interest of neutron radiography to better understand deterioration processes in limestones and to acquire information useful for restoration projects

  5. Properies of binder systems containing cement, fly ash, and limestone powder

    Directory of Open Access Journals (Sweden)

    Krittiya Kaewmanee

    2014-10-01

    Full Text Available Fly ash and limestone powder are two major widely available cement replacing materials in Thailand. However, the current utilization of these materials is still not optimized due to limited information on properties of multi-binder systems. This paper reports on the mechanical and durability properties of mixtures containing cement, fly ash, and limestone powder as single, binary, and ternary binder systems. The results showed that a single binder system consisting of only cement gave the best carbonation resistance. A binary binder system with fly ash exhibited superior performances in long-term compressive strength and many durability properties except carbonation and magnesium sulfate resistances, while early compressive strength of a binary binder system with limestone powder was excellent. The ternary binder system, taking the most benefit of selective cement replacing materials, yielded, though not the best, satisfactory performances in almost all properties. Thus, the optimization of binders can be achieved through a multi-binder system.

  6. A correlation of Sr isotope stratigraphy and foraminiferal biostratigraphy in tertiary limestones of Papua New Guinea

    International Nuclear Information System (INIS)

    Allan, T.L.; Trotter, J.A.; Whitford, D.J.; Korsch, M.J.

    2000-01-01

    Strontium isotopic and stratigraphic data collected from the Darai Limestone of Papua New Guinea clearly demonstrate a systematic relationship between bulk 87 Sr/ 86 Sr ratio and index foraminiferal composition that closely reflects the relative stratigraphical range of the foraminifera in this region. A graphic correlation of stratigraphic, strontium isotopic and age ranges of the major index taxa permits direct evaluation of limestone age and isotopic composition in the Darai Limestone. The age of the Tf 1 /Tf 2 boundary (∼12.2 Ma) is significantly younger than the accepted estimate of ∼15.0 Ma (plankton Zone N9) and the Te/Tf boundary (∼20.3 Ma) is older than the generally accepted age of ∼l 8.5 Ma (plankton Zone N6)

  7. A NEW DAONELLA FROM THE LADINIAN PLATFORM OF THE ESINO LIMESTONE (SOUTHERN ALPS, ITALY

    Directory of Open Access Journals (Sweden)

    CRISTIANO LARGHI

    2006-03-01

    Full Text Available The bivalve Daonella Mojsisovics, 1874 is very common in the Middle Triassic pelagic facies, whereas the record of this genus from shallow water limestones is rare. In the present paper a new species of Daonella, named D. pseudograbensis, is described from the Esino Limestone, a Ladinian (Middle Triassic carbonate platform in the central Southern Alps. The species is described from Brembana Valley, where the Esino Limestone is rather rich in bioclastic lenses yielding faunas with bivalves, cephalopods, gastropods, brachiopods, corals and calcareous algae. Daonella pseudograbensis n. sp. is based on very well preserved specimens, which are often articulated and closed, all coming from the same locality. The new species shows a narrow range of intraspecific and ontogenetic morphologic variations. It is easy distinguishable from the other species of the genus for the outline and ornamentation; it therefore differs from D. grabensis Kittl, 1912, the most similar species, for the longer anterior dorsal margin.Pdf

  8. Successful experience with limestone and other sorbents for combustion of biomass in fluid bed power boilers

    Energy Technology Data Exchange (ETDEWEB)

    Coe, D.R. [LG& E Power Systems, Inc., Irvine, CA (United States)

    1993-12-31

    This paper presents the theoretical and practical advantages of utilizing limestone and other sorbents during the combustion of various biomass fuels for the reduction of corrosion and erosion of boiler fireside tubing and refractory. Successful experiences using a small amount of limestone, dolomite, kaolin, or custom blends of aluminum and magnesium compounds in fluid bed boilers fired with biomass fuels will be discussed. Electric power boiler firing experience includes bubbling bed boilers as well as circulating fluid bed boilers in commercial service on biomass fuels. Forest sources of biomass fuels fired include wood chips, brush chips, sawmill waste wood, bark, and hog fuel. Agricultural sources of biomass fuels fired include grape vine prunings, bean straw, almond tree chips, walnut tree chips, and a variety of other agricultural waste fuels. Additionally, some urban sources of wood fuels have been commercially burned with the addition of limestone. Data presented includes qualitative and quantitative analyses of fuel, sorbent, and ash.

  9. Modelling of catalytic oxidation of NH3 and reduction of NO on limestone during sulphur capture

    DEFF Research Database (Denmark)

    Kiil, Søren; Bhatia, Suresh K.; Dam-Johansen, Kim

    1996-01-01

    activity with respect to each species involved. An existing particle model, the Grain-Micrograin Model, which simulates sulphur capture on limestone under oxidizing conditions is considered in the modelling. Simulation results in good qualitative agreement with experimental data are obtained here......A theoretical study of the complex transient system of simultaneous sulphur capture and catalytic reactions of N-containing compounds taking place on a single limestone particle is conducted. The numerical technique developed previously by the authors (Kiil et al. 1994) based on collocation...... for the catalytic chemistry of NH3 during simultaneous sulphur capture on a Stevns Chalk particle. The reduction of NO by NH3 over CaSO4 (which is the product of the reaction between SO2, O2 and limestone) was found to be important because this reaction could explain the change in selectivity with increased solid...

  10. Thermochemical degradation of limestone aggregate concrete on exposure to sodium fire

    International Nuclear Information System (INIS)

    Premila, M.; Sivasubramanian, K.; Amarendra, G.; Sundar, C.S.

    2008-01-01

    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

  11. Elemental analysis of some West Malaysian limestones using neutron activation, delayed neutron and electron microprobe analysis

    International Nuclear Information System (INIS)

    Amin, Y.M.; Kamaluddin, B.; Mahat, R.H.

    1990-01-01

    Limestone stratigraphy in Malaysia has been and is dependent almost entirely in palaeontology. However fossil localities are sporadic and as such a new fossil discovery mean the necessity for a complete re-appraisal of the stratigraphy. The almost complete dependence upon palaeontology results from the difficulties of stratigraphy correlation of isolated outcrops, from the cover of tropical vegetation and from the often complex folding and faulting which has been imposed on the geosyn-clinical rocks by the Indonesian-Thai-Malayan orogeny. So by studying the elemental composition of limestones accurately, we would be able to correlate outcrops and other stratigraphic samples independent of fossil finds. The use of delayed neutron analysis would also determine the concentration of uranium and thorium accurately. This study, in conjunction with thermoluminescence and fission track studies, would able us to date the age of the limestones

  12. Industrial application of limestone deposits of kohat, NWFP: a research towards the sustainability of the deposits

    International Nuclear Information System (INIS)

    Bilqees, R.; Shah, T.

    2007-01-01

    Chemical analyses, petrographic studies and physical tests of limestone deposits in the vicinity of kohat along Bannu Road, Hangu Road and Rawalpindi Road were carried out to categorize these reserves, locality-wise, for their specified industrial uses. Limestone of kohat area was found to be generally good for construction purposes. The deposits on the Hangu Road were of good quality with more then 97% CaCO/sub 3/ and suitable for use in chemical, iron and steel industries, for glass making, soda ash manufacture etc. The deposit of Bannu Road with 96.5% CaCO/sub 3/ can be used for sugar refining, paint industry, flue gas desulphurization, animal feed etc. The limestone deposit of Rawalpindi Road is inferior in quality having 95.2% CaCO/sub 3/. It can be utilized in rubber industry, as ceramic whiting, building materials, rock wool etc. (author)

  13. The French electricity report 2009

    International Nuclear Information System (INIS)

    2010-01-01

    RTE is the company responsible for running the French electricity transmission system. It is a public service operator, tasked with operating, maintaining and developing the high and extra high voltage network. It guarantees the reliability and proper operation of the power network. These missions were entrusted to it by the Law of 10 February 2000. With 100,000 km of lines between 63,000 and 400,000 volts and 45 cross-border lines, the network operated by RTE is the biggest in Europe. In 2008, RTE posted turnover of euros 4,221 m and currently employs around 8,500 staff. RTE, by virtue of the missions entrusted to it by the Law of 10 February 2000, is the central player in the French power system. For the purpose of maintaining the real time balance between supply and demand, and managing contractual relations with customers connected to its network, RTE monitors all the electrical energy that enters and leaves the public transmission system. Through its management of the 45 interconnection lines linking France with its neighbours, RTE also tracks all import and export data, on behalf of players in the French and European electricity market. RTE constantly records and examines data provided by all market players. Using the data, monthly and annually, it publishes exhaustive figures for the French power system (demand, generation, imports and exports), which offer the only truly accurate reflection of the real state of the sector's economy. This report presents these figures for the year 2009. Contents: 1 - French electricity demand down by 1.6% on 2008; 2 - A drop in French electricity generation; 3 - The balance of cross-border exchanges falls, but remains positive; 4 - RTE continues to invest in a robust network capable of keeping up with developments in the electricity industry; 5 - Appendix 1: New infrastructures on the RTE network in 2009; 6 - Appendix 2: Electricity quality; 7 - Appendix 3: Mature market mechanisms

  14. Optical performance of hybrid porous silicon-porous alumina multilayers

    Science.gov (United States)

    Cencha, L. G.; Antonio Hernández, C.; Forzani, L.; Urteaga, R.; Koropecki, R. R.

    2018-05-01

    In this work, we study the optical response of structures involving porous silicon and porous alumina in a multi-layered hybrid structure. We performed a rational design of the optimal sequence necessary to produce a high transmission and selective filter, with potential applications in chemical and biosensors. The combination of these porous materials can be used to exploit its distinguishing features, i.e., high transparency of alumina and high refractive index of porous silicon. We assembled hybrid microcavities with a central porous alumina layer between two porous silicon Bragg reflectors. In this way, we constructed a Fabry-Perot resonator with high reflectivity and low absorption that improves the quality of the filter compared to a microcavity built only with porous silicon or porous alumina. We explored a simpler design in which one of the Bragg reflectors is replaced by the aluminium that remains bound to the alumina after its fabrication. We theoretically explored the potential of the proposal and its limitations when considering the roughness of the layers. We found that the quality of a microcavity made entirely with porous silicon shows a limit in the visible range due to light absorption. This limitation is overcome in the hybrid scheme, with the roughness of the layers determining the ultimate quality. Q-factors of 220 are experimentally obtained for microcavities supported on aluminium, while Q-factors around 600 are reached for microcavities with double Bragg reflectors, centred at 560 nm. This represents a four-fold increase with respect to the optimal porous silicon microcavity at this wavelength.

  15. General and Professional French Courses

    CERN Document Server

    2007-01-01

    These courses are open to all persons working on the CERN site, and to their spouses. For registration and further information on the courses, please consult our Web pages: http://cern.ch/Training or contact Nathalie Dumeaux, tel. 78144. Writing Professional Documents in French The next session will take place from 8 October to 14 December 2007. This course is designed for people with a good level of spoken French. Duration: 30 hours (3 hours a week) Price: 660 CHF (for a minimum of 8 students). For registration and further information, please consult our Web pages: http://cern.ch/Training or contact Nathalie Dumeaux, tel. 78144.

  16. French regulation and waste management

    International Nuclear Information System (INIS)

    1984-08-01

    The organization and the role played by French safety authorities for waste management are described. The French policy for storage and conditioning: basic objectives and waste management optimization are specified. Safety requirements are based on the barrier principle, they are mentioned for packaging and storage. The ''Institut de Protection et Surete Nucleaire'' deals not only with safety analysis but also help the ''autorites ministerielles'' for the development of fundamental safety rules. Examples for spent fuel storage and radioactive materials transport are treated in appendixes [fr

  17. Sedimentary and environmental history of the Late Permian Bonikowo Reef (Zechstein Limestone, Wuchiapingian, western Poland

    Directory of Open Access Journals (Sweden)

    Paweł Raczyński

    2017-07-01

    Full Text Available The Bonikowo Reef occurs in the central part of the Zechstein Limestone Basin in western Poland and was growing on the topmost edges of tilted blocks and/or on the top of uplifted horsts of the Brandenburg–Wolsztyn–Pogorzela High. Its size is ca. 1.6 km2. The Bonikowo Reef shows the thickest reef section (90.5 m recorded in the High. The Zechstein Limestone unit is represented mostly by limestones, often thoroughly recrystallized, although the macrotextures and biota of the boundstone are identifiable in most cases. The drillcore section is a mixture of boundstones (microbial and bryozoan, wackestones, packstones and grainstones, which often co-occur. The δ13C and δ18O values for both calcite (avg. 3.8 ± 0.8‰ and −3.4 ± 1.7‰, respectively and dolomite (avg. 3.5 ± 0.7‰ and −5.2 ± 1.3‰, respectively are transitional between the values previously reported for condensed sequences of the basinal facies and larger reef complexes. The biofacies of the Bonikowo Reef are very similar to those recognized in other reefs of the Brandenburg–Wolsztyn–Pogorzela High, which owe their origin to the destruction of bryozoan boundstones. The biota composition is typical and characteristic of other Zechstein Limestone reefs. However, the Bonikowo Reef demonstrates the importance of microbialites, laminar and nodose encrustations, in the growth and cohesion of the Zechstein Limestone reefs. Such encrustations abound within the Zechstein Limestone although, in many cases, the real nature of the encrustations is difficult to ascertain. These laminated encrustations show great similarity to Archaeolithoporella that is one of the most important Permian reef-building organisms. The encrustations considered to represent Archaeolithoporella were also previously recorded in the Zechstein Limestone of western Poland and in its stratigraphic equivalent, the Middle Magnesian Limestone of Northeast England. The lower part of the sequence shows

  18. Pliocene Te Aute limestones, New Zealand : expanding concepts for cool-water shelf carbonates

    International Nuclear Information System (INIS)

    Nelson, C.S.; Winefield, P.R.; Hood, S.D.; Caron, V.; Pallentin, A.; Kamp, P.J.J.

    2003-01-01

    Acceptance of a spectrum of warm- through cold-water shallow-marine carbonate facies has become of fundamental importance for correctly interpreting the origin and significance of all ancient platform limestones. Among other attributes, properties that have become a hallmark for characterising many Cenozoic non-tropical occurrences include: (1) the presence of common bryozoan and epifaunal bivalve skeletons; (2) a calcite-dominated mineralogy; (3) relatively thin deposits exhibiting low rates of sediment accumulation; (4) an overall destructive early diagenetic regime; and (5) that major porosity destruction and lithification occur mainly in response to chemical compaction of calcitic skeletons during moderate to deep burial. The Pliocene Te Aute limestones are non-tropical skeletal carbonates formed at paleolatitudes near 40-42 degrees S under the influence of commonly strong tidal flows along the margins of an actively deforming and differentially uplifting forearc basin seaway, immediately inboard of the convergent Pacific-Australian plate boundary off eastern North Island, New Zealand. This dynamic depositional and tectonic setting strongly influenced both the style and subsequent diagenetic evolution of the limestones. Some of the Te Aute limestones exhibit the above kinds of 'normal' non-tropical characteristics, but others do not. For example, many are barnacle and/or bivalve dominated, and several include attributes that at least superficially resemble properties of certain tropical carbonates. In this regard, a number of the limestones are infaunal bivalve rich and dominated by an aragonite over a calcite primary mineralogy, with consequently relatively high diagenetic potential. Individual limestone units are also often rather thick (e.g., up to 50-300 m), with accumulation rates from 0.2 to 0.5 m/ka, and locally as high as 1 m/ka. Moreover, there can be a remarkable array of diagenetic features in the limestones, involving grain alteration and

  19. Rapid method to determine actinides and 89/90Sr in limestone and marble samples

    International Nuclear Information System (INIS)

    Maxwell, S.L.; Culligan, Brian; Hutchison, J.B.; Utsey, R.C.; Sudowe, Ralf; McAlister, D.R.

    2016-01-01

    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 / 90 Sr are separated using extraction chromatographic resins and measured radiometrically. The advantages of sodium hydroxide fusion versus other fusion techniques will be discussed. This approach has a sample preparation time for limestone and marble samples of <4 h. (author)

  20. Improvement of operational properties of shell limestone building materials by polysulfide solution impregnation

    Directory of Open Access Journals (Sweden)

    MASSALIMOV Ismail Alexandrovich

    2017-06-01

    Full Text Available The data of studies on the effectiveness of impregnation with polysulfide solutions of shell limestone used as facing and wall material, as well as for the manufacture of road products are presented. Modification of the limestone with the impregnating composition «Akvastat» created by the authors which is sulfur-containing water-based solution of calcium polysulfide containing alcohols and surfactants, can significantly reduce water absorption and increase durability of limestone. Impregnating composition on the basis of calcium polysulfide possesses density of 1.22–1.24 g/cm3, the infiltrant penetrates into the pore structure of limestone to a depth of 4 cm or more, depending on the density and structure of the sample. While the material is drying, sulfur nanoparticles are crystallized from the polysulfide solution in its pores. They partially fill pore space and form protective durable insoluble hydrophobic coating that impedes the penetration of water into the pores of the limestone, but preserves its vapor permeability, which is important for wall and decoration materials. The evaluation of protective coatings was performed with laser particle size analyzer, scanning probe microscope and a diffractometer. It showed that the average size of the particles forming the protective coating is in the range of 20–25 nm, the particles shape is spherical, the particles are elemental sulfur with orthorhombic structure of the crystal lattice. The processing of shell limestone with calcium polysulphide solution provides formation of coating based on nanosized sulfur on the surface of stone pores. The coating partially fills the pore space and, as it is hydrophobic, reduces the water absorption of the samples by a factor of 5–8, increases their average density by 22–27%, strength in 1,2–1,3 times, the softening factor by 6–19%, that makes possible to predict the increase of the durability of building materials based on shell limestone to 1

  1. Performance of japanese quails fed feeds containing different corn and limestone particle sizes

    OpenAIRE

    Berto,DA; Garcia,EA; Móri,C; Faitarone,ABG; Pelícia,K; Molino,AB

    2007-01-01

    This study aimed at evaluating performance and egg quality of Japanese quails fed feeds containing different corn and limestone particle sizes. A total number of 648 birds in the peak of production was distributed in a random complete block experimental design, using a 2x3 factorial arrangement (2 corn particle sizes and 3 limestone particle sizes). Birds were designated to one of two blocks, with six replicates of 18 birds each. Mean geometric diameter (MGD) values used were 0.617mm and 0.72...

  2. Hydration of Blended Portland Cements Containing Calcium-Aluminosilicate Glass Powder and Limestone

    DEFF Research Database (Denmark)

    Moesgaard, M; Poulsen, Søren Lundsted; Herfort, D

    2012-01-01

    M. MOESGAARD, S.L. POULSEN, D. HERFORT, M. STEENBERG, L.F. KIRKEGAARD, J. SKIBSTED, Y. YUE, Hydration of Blended Portland Cements Containing Calcium-Aluminosilicate Glass Powder and Limestone, Journal of the American Ceramic Society 95, 403 – 409 (2012).......M. MOESGAARD, S.L. POULSEN, D. HERFORT, M. STEENBERG, L.F. KIRKEGAARD, J. SKIBSTED, Y. YUE, Hydration of Blended Portland Cements Containing Calcium-Aluminosilicate Glass Powder and Limestone, Journal of the American Ceramic Society 95, 403 – 409 (2012)....

  3. Differences between silica and limestone concretes that may affect their interaction with corium

    International Nuclear Information System (INIS)

    Journeau, C.; Haquet, J. F.; Piluso, P.; Bonnet, J. M.

    2008-01-01

    Recent Molten Core Concrete Interaction tests performed at Argonne National Laboratory and at CEA Cadarache have shown that, whereas the ablation of limestone-rich concretes is almost isotropic, the ablation of silica-rich concretes is much faster towards the sides than towards the bottom of the cavity. The following differences exists between limestone-rich and silica-rich concretes: limestone concretes liberate about twice as much gas, at a given ablation rate than siliceous concretes (more than 50% more at constant heat flux) and this can affect pool hydraulics and crust stability: limestone concrete has a higher liquidus temperature than siliceous concrete and molten limestone concrete has a larger diffusion coefficient and can more easily dissolve a corium crust than siliceous melt; limestone aggregates are destroyed by de-carbonation at around 1000 K while silica aggregates melt only above 2000 K, so that floating silica aggregates can form cold spots increasing corium solidification near the interface; de-carbonation of limestone leads to a significant shrinkage of concrete melt volume compared to the cold solid that hampers the mechanical stability of overlying crusts; the chemical composition of molten mortar (sand + cement) and concrete (sand + gravel + cement) is close for limestone-rich concretes while it is different for siliceous concretes, so that the melt composition may vary significantly in case of non-simultaneous melting of the siliceous concrete constituents; molten silicates have a large viscosity, so that transport properties are different for the two types of concretes. The small range of plant concrete compositions that have been considered for MCCI experiments has not yet been found sufficient to determine which of the above-mentioned differences is paramount to explain the observed difference in ablation patterns. Separate Effect Tests using specially-designed 'artificial concretes' and prototypic corium would provide the necessary

  4. Carbonate Minerals with Magnesium in Triassic Terebratula Limestone in the Term of Limestone with Magnesium Application as a Sorbent in Desulfurization of Flue Gases

    Science.gov (United States)

    Stanienda-Pilecki, Katarzyna

    2017-09-01

    This article presents the results of studies of Triassic (Muschelkalk) carbonate rock samples of the Terebratula Beds taken from the area of the Polish part of the Germanic Basin. It is the area of Opole Silesia. The rocks were studied in the term of possibility of limestone with magnesium application in desulfurization of flue gases executed in power plants. Characteristic features of especially carbonate phases including magnesium-low-Mg calcite, high-Mg calcite, dolomite and huntite were presented in the article. They were studied to show that the presence of carbonate phases with magnesium, especially high-Mg calcite makes the desulfurization process more effective. Selected rock samples were examined using a microscope with polarized, transmitted light, X-ray diffraction, microprobe measurements and FTIR spectroscopy. The results of studies show a domination of low magnesium calcite in the limestones of the Terebratula Beds. In some samples dolomite and lower amounts of high-Mg calcite occurred. Moreover, huntite was identified. The studies were very important, because carbonate phases like high-Mg calcite and huntite which occurred in rocks of the Triassic Terebratula Beds were not investigated in details by other scientists but they presence in limestone sorbent could influence the effectiveness of desulfurization process.

  5. Diagenetic evolution and stable isotopes of Lower Permian platform marginal carbonates (Trogkofel Limestone, Carnic Alps, Austria)

    Science.gov (United States)

    Schaffhauser, Maria; Krainer, Karl; Sanders, Diethard Gerald; Spötl, Christoph

    2010-05-01

    The Trogkofel massif in the Carnic Alps, Austria/Italy, consists of a succession up to 400 m thick of limestones deposited along a platform margin (Trogkofel Limestone; Artinskian). The top of the Trogkofel Limestone is erosively overlain by the Tarvis Breccia. Up-section, the Trogkofel Limestone consists of well-bedded shallow-water bioclastic limestones with intercalated mud mounds, overlain by thick-bedded to unbedded limestones (bioclastic grainstones, packstones, rudstones) and cementstone mounds rich in phylloid algae, Tubiphytes, bryozoans and Archaeolithoporella. In the cementstone mounds, bioclasts are coated by thick fringes and botryoids of fibrous calcite, and of calcite spar that probably represents calcitized aragonite. Primary and intrinsic pores are filled by microbialite, and/or by mudstone to bioclastic wackestone. Shallow-water bioclastic grainstones are cemented by isopachous fringes of fibrous calcite, or by sparry calcite. Throughout the succession, evidence for meteoric-vadose dissolution is present. The Trogkofel Limestone is riddled by palaeokarstic dykes and caverns filled by (a) isopachous cement fringes up to a few decimetres thick, and/or (b) by red, geopetally-laminated lime mudstone to bio-lithoclastic wackestone; geopetal laminasets locally display convolute bedding. Small dissolution cavities are filled by grey internal sediment, or by crystal silt. Brecciated internal sediments overlain by unbrecciated, geopetally-laminated infillings record deformation during or after deposition of the Trogkofel Limestone. Polyphase fractures cemented by calcite may cross-cut both internal sediments and host rock. In the Trogkofel Limestone, local dolomitization is common. Replacement dolomites show a wide range of shapes and fabrics, including: (a) fine-crystalline anhedral xenotopic fabric, (b) coarse-crystalline subhedral to euhedral, hypidiotopic to idiotopic fabric of turbid or optically zoned crystals, and (c) saddle dolomite as replacement

  6. The french electric power evaluation 2005

    International Nuclear Information System (INIS)

    2006-01-01

    This document takes stock on the french electric power situation for the year 2005. It provides information on the consumption the trade, the production, the french market and the RTE (Electric power transport network) infrastructure. (A.L.B.)

  7. French how to speak and write it

    CERN Document Server

    Lemaître, Joseph

    1978-01-01

    Probably the most delightful, useful, and comprehensive elementary book available for learning spoken and written French, either with or without a teacher. Includes colloquial French conversations as well as grammar, vocabulary, and idiom studies.

  8. Directory of the French nuclear industry

    International Nuclear Information System (INIS)

    2002-10-01

    This directory includes data sheets on the French companies operating in the nuclear industry. It begins with an introduction containing information on the French nuclear industry: 1 - nuclear power development in France (national energy plan, history, organization, economic advantages, reactors); 2 - French operator: Electricite de France (EdF); 3 - the industry (Areva, Cogema, mining activities, uranium chemistry and enrichment, processing, recycling, engineering, services, Framatome ANP); 4 - R and D and knowledge dissemination: French atomic energy commission (CEA); 5 - nuclear safety, security, control and regulation: nuclear safety authority (ASN), general direction of nuclear safety and radioprotection (DGSNR), institute of radioprotection and nuclear safety (IRSN), radioactive wastes, ANDRA's role; 6 - associations: French atomic forum (FAF), French nuclear industry trade association (GIIN), French nuclear energy society (SFEN), French radiation protection society (SFRP). Then, the data sheets of the directory follows. (J.S.)

  9. The French emirs of uranium

    International Nuclear Information System (INIS)

    Lucas, N.

    1978-01-01

    The French energy plan is described under the following heads: structure of supply/use; nuclear energy; oil consumption; coal consumption; gas consumption; energy conservation; renewable resources. The section on nuclear energy covers: nuclear programmes, uranium supplies (mining and enrichment), fuel fabrication and reprocessing, finance and economics, political and administrative aspects, nuclear trade, development of fast breeder reactor. (U.K.)

  10. Progress of French nuclear programme

    International Nuclear Information System (INIS)

    Pierrard, J.-H.

    1981-02-01

    The aims of the French nuclear programme launched in 1974 are briefly recalled to mind, as are the projects completed at the end of 1980. The operating results mentioned, particularly concern the new PWR units brought into commercial service in 1980 [fr

  11. Hopes doomed for French photovoltaic

    International Nuclear Information System (INIS)

    Piro, P.

    2013-01-01

    The photovoltaic industry has lost 15000 jobs in 2 years in France and the emergency measures taken by French authorities seem to be not sufficient to curb the trend. Some measures have led to delay or even cancel some projects while what is the most important today is to generate enough activity in small and intermediate enterprises to safeguard jobs

  12. Two new French quality labels

    Energy Technology Data Exchange (ETDEWEB)

    Bresler, Ines

    2012-07-01

    'Origine France Garantie' and 'AQPV' are the new product labels that were presented in France in 2011. While the first is aimed at the entire industry, the latter is an effort to strengthen the PV industry. By raising the enthusiasm for local products, the French government hopes to keep the flood of foreign imports at bay. (orig.)

  13. English-French Cognate Dictionary.

    Science.gov (United States)

    Hammer, Petra; Monod, Madeleine

    This dictionary contains a word list of 10,993 English-French cognates (words with the same or similar spelling and meaning in both languages), including some loan words from other languages. A systematic review of the Larousse "Dictionnaire Moderne Francais--Anglais" (1960) provided this list of cognates. Deceptive cognates, or words…

  14. Fair period in French solar

    International Nuclear Information System (INIS)

    Pradel, P.

    1997-01-01

    The French solar industry decreased from 1992, but five years later, the situation changes and this industry is increasing again. The energy policy takes in account the renewable energies in a greater part, secondly, the technical reliability and a prices decreasing allow to this market to gain some ground. (N.C.)

  15. Revis(iting French palatalization

    Directory of Open Access Journals (Sweden)

    Ali Tifrit

    2016-06-01

    Full Text Available This paper explores the diachrony of French and reconsiders the classical analysis of French palatalizations. It is widely admitted that the transition from Latin dorsal stops to French palatal fricatives is triggered by an external palatalizing object which affects the constitution of the targeted consonant. While this analysis can satisfyingly explain the palatalization of dorsals before /i/, it makes the palatalization before /a/, which occurred a few centuries later, completely opaque. Revising the internal structure and the melody used to describe segments (Government Phonology 2.0 – Pöchtrager 2006 allows us to give a unified analysis of both palatalizations: whether /i/ or /a/, the vocalic environment is indeed the trigger, as it interferes with the structure of dorsals and lead to internal changes. However, while /i/ adds palatality to the consonant, /a/, by its lack of melody (Pöchtrager & Živanović 2010, leads to an internal reconfiguration of the dorsal, which already contains . In other words, we face two kinds of palatalization: an external one and an internal one. Furthermore, our analysis takes the intermediate stages from Latin dorsals to French palatals into consideration and attested dialectal variations observed in Northern France.

  16. Accident management on french PWRS

    International Nuclear Information System (INIS)

    Queniart, D.

    1990-06-01

    After a brief recall of French safety rationale, the reactor operation and severe accident management is given. The research and development aimed at developing accident management procedures and emergency organization in France for the case of a NPP accident are also given

  17. The Kyoto conference: French perspective

    International Nuclear Information System (INIS)

    Orliange Philippe

    1998-02-01

    The present article approaches the problem of the climate change from a French perspective, describing the process that let the topic acquire importance in the national government level. Also, they stand out the difficulties generated in the negotiations of the Kyoto Protocol, because the opposing positions have United States and the European block

  18. General and Professional French Courses

    CERN Document Server

    HR Department

    2011-01-01

    The next session will take place from 10th of October to 16th of December 2011. These courses are open to all persons working on the CERN site, and to their spouses. For registration and further information on the courses, please consult our Web pages: http://hr-training.web.cern.ch/hr-training/ or contact Kerstin Fuhrmeister (kerstin.fuhrmeister@cern.ch) Oral Expression This course is aimed for students with a good knowledge of French who want to enhance their speaking skills. Speaking activities will include discussions, meeting simulations, role-plays etc. Suitable candidates should contact Kerstin Fuhrmeister (70896) or Martine Zuffi (73483) in order to arrange an appointment for a test. The next session will take place from 10th of October to 16th of December 2011. Writing professional documents in French These courses are designed for non-French speakers with a very good standard of spoken French. Suitable candidates should contact Kerstin Fuhrmeister (70896) or Martine Zuffi (73483) in order to arr...

  19. General and Professional French Courses

    CERN Multimedia

    HR Department

    2011-01-01

    The next session will take place from 30th of January to 5th of April 2012. These courses are open to all persons working on the CERN site, and to their spouses. For registration and further information on the courses, please consult our Web pages: http://hr-training.web.cern.ch/hr-training/ or contact Kerstin Fuhrmeister (kerstin.fuhrmeister@cern.ch) Oral Expression This course is aimed for students with a good knowledge of French who want to enhance their speaking skills. Speaking activities will include discussions, meeting simulations, role-plays etc. Suitable candidates should contact Kerstin Fuhrmeister (70896) or Martine Zuffi (73483) in order to arrange an appointment for a test. The next session will take place from 30th of January to 5th of April 2012. Writing professional documents in French These courses are designed for non-French speakers with a very good standard of spoken French. Suitable candidates should contact Kerstin Fuhrmeister (70896) or Martine Zuffi (73483) in order to arrange an ...

  20. Submarine terrace limestones from the continental slope off Saurashtra-Bombay: Evidence of Late Quaternary neotectonic activity

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, V.P.; Veerayya, M.

    cements occur as isopachous crusts. Dissolution and clotting of aragonite needles and drusy calcite in the interstices indicate cementation of the limestones at inter-tidal conditions. The age of the limestones is 11,900 years BP. These imply that the 130...

  1. Replacement of Eocene white sandy limestone in historical buildings : over 100 years of practice in the Netherlands

    NARCIS (Netherlands)

    Quist, W.J.; Nijland, T.G.; Hees, R.P.J. van

    2013-01-01

    This paper discusses the replacement of white sandy limestone (Gobertange and Lede or Balegem) in the Netherlands in (successive) restorations from the mid-19th century onwards. White sandy limestone, transported from the southern part of the Low Countries (now Belgium), was extensively used in the

  2. Lithofacies and petrophysical properties of Portland Base Bed and Portland Whit Bed limestone as related to durability

    NARCIS (Netherlands)

    Dubelaar, C.W.; Engering, S.; Hees, R.P.J. van; Koch, R.; Lorenz, H.G.

    2003-01-01

    This study focuses on the differences in lithofacies and petrophysical properties of Base Bed and Whit Bed Portland limestone and the presumed relationships between these characteristics and the durability of this building stone. As Portland limestone probably will be used as a stone for several

  3. Lithofacies and Petrophysical Properties of Portland Base Bed and Portland Whit Bed Limestone as Related to Durability

    NARCIS (Netherlands)

    Dubelaar, C.W.; Engering, S.; Van Hees, R.P.J.; Koch, R.; Lorenz, H.G.

    2003-01-01

    This study focuses on the differences in lithofacies and petrophysical properties of Base Bed and Whit Bed Portland limestone and the presumed relationships between these characteristics and the durability of this building stone. As Portland limestone probably will be used as a stone for several

  4. Radioactivity in French bottled waters

    Energy Technology Data Exchange (ETDEWEB)

    Loyen, J.; Brassac, A.; Augeray, C.; Fayolle, C.; Gleizes, M. [Institut de Radioprotection et de Surete Nucleaire - IRSN (France)

    2014-07-01

    As IRSN is considered as a reference laboratory for radioactivity measurements, French health ministry and French nuclear safety authority asked IRSN to carry out a study in order to get a fresh and complete status of radiological water quality of French bottled waters. The study was carried out during 12 months in 2012. A total of 142 bottled waters samples were analyzed (75 spring waters and 67 natural mineral waters). The laboratories of IRSN were in charge of: - systematic measurement of radioactivity following requirements of the French health ministry (Circulaire du 13/06/2007) regarding the monitoring and management of sanitary risk linked to the presence of radionuclides in drinking waters (natural mineral waters excepted). - systematic uranium mass concentration determination; - a few radon-222 gas measurements for waters in glass bottles. This study is a flash assessment of radiological characteristics of French bottled waters, at the analysis date for the sample received. It was done in informative way and was not done for regulatory control purposes.. This study has shown that: - all bottled waters analyzed have a tritium activity concentration lower than the quality reference value of 100 Bq/l of the French regulation; - More than 105 bottled waters analyzed (80% of the springs waters and 70% of natural mineral waters received) have a gross alpha activity concentration lower than the guideline value of 0,1 Bq/l of the French regulation; - All bottled waters analyzed have a residual gross beta activity concentration lower than the guideline value of 1 Bq/l of the French regulation; - All bottled waters analyzed have a uranium mass concentration lower than the provisory guideline value of 30 μg/l of the WHO for drinking waters; - radon-222 was only significantly measured once upon 6 glass bottled waters with a value far below the reference value of 100 Bq/l of the future European Directive on drinking waters. For 32 bottled waters with gross alpha

  5. High-temperature CO2 capture cycles of hydrated limestone prepared with aluminum (hydr)oxides derived from kaolin

    International Nuclear Information System (INIS)

    Wang, Ke; Zhao, Pengfei; Guo, Xin; Han, Dongtai; Chao, Yang

    2014-01-01

    Highlights: • Hydrated limestone exhibited a higher reactivity and stability. • Microstructure of hydrated limestone was significantly improved. • Hydrated limestone still suffered less loss-incapacity. • Hydrated limestone sorbents with kaolin-based binders were prepared and characterized. • Sorbents prepared from hydrated limestone and Al(OH) 3 binder are a promising sorbent. - Abstract: A simple and convenient process was used to improve the utilization of natural limestone and kaolin for calcium looping technology and environmental applications. The calcined natural limestone modified with the distilled water (denoted as Limestone-W), was systematically studied and compared with the other CaO sorbents (calcium acetate, calcium D-gluconate and calcined natural limestone). These CaO-based sorbents were tested for their CO 2 capture behavior through 20 carbonation/calcination cycles in a thermo-gravimetric analyzer (TGA). Their morphology, pore structure and phase composition before and after carbonation/calcination cycles were determined by scanning electron microscopy, nitrogen adsorption, and X-ray diffraction. The first-cycle and multicycle sorption results revealed that the Limestone-W sorbent exhibited a relatively faster reaction rate and higher cyclic CO 2 capture. The characterization data indicated that the Limestone-W was composed of a special calcium oxide structure with lower crystalline and higher porosity nanoparticles, which appeared to be the main reasons for its higher CO 2 capture capability. However, the Limestone-W still suffered loss of reactivity, even though it was less pronounced than the other CaO sorbent. To avoid this unfavorable effect, a thermally stable inert material (aluminum hydroxide derived from kaolin) was incorporated into the Limestone-W structure. This new sorbent revealed higher stability because the formation of a stable framework of Ca 12 Al 14 O 33 particles hindered densification and sintering of the CaO phase

  6. The acquisition of French in multilingual contexts

    CERN Document Server

    Guijarro-Fuentes, Pedro; Müller, Natascha

    2015-01-01

    This volume brings together new research from different theoretical paradigms addressing the acquisition of French as a second language. It focuses on the acquisition of French in combination with different languages and enriches our understanding of the particularities of French and the role of language combinations in the acquisition process.

  7. Slang Usage of French by Young Americans.

    Science.gov (United States)

    Ensz, Kathleen Y.

    1985-01-01

    Describes reactions of native French speakers to usage of French slang by young American students. French-speaking participants rated 30 tape-recorded slang expressions. Their reactions were evaluated in relation to the sex, profession, age, and residence of the respondents. Results show attitudes critical of the use of slang in general. (SED)

  8. TEACHING AND LEARNING OF FRENCH: IMPERATIVE FOR ...

    African Journals Online (AJOL)

    Prof

    It is important to note that, the teaching of French was introduced into the ... subjects like English to the detriment of French language is a proof of that .... To encourage teachers to lead the learners to use French language as a tool for .... professionals, thereby placing Nigeria at a disadvantage in terms of job creation.

  9. Commercial French in a Liberal Arts Setting.

    Science.gov (United States)

    Abrate, Jayne

    Drury College (Missouri) has developed a commercial French course that is practical, situation-oriented, and provides instruction in correspondence and translation. The course is considered part of the cultural segment of the French program. It enrolls majors in business, French, and a variety of other disciplines, and emphasizes contextual…

  10. Report: Immersion French at Meriden Junior School

    Science.gov (United States)

    Esposito, Marie-Josee

    2006-01-01

    In this article, the author describes the French immersion program at Meriden Junior School, an Anglican school for girls from pre-Kindergarten to Year 12 in Sydney. Four teachers (one of whom is the coordinator) and three assistants are involved in the program. They include six French native speakers and one non-French-born teacher who speaks…

  11. Lightweight concrete with Algerian limestone dust. Part II: study on 50% and 100% replacement to normal aggregate at timely age

    Directory of Open Access Journals (Sweden)

    S. Kitouni

    2015-12-01

    Full Text Available Abstract A control lightweight concrete (LWC mixture made with 50% and 100% of limestone as a replacement of coarse aggregates in weight was prepared. Limestone is used for economical and environmental concern. The concrete samples were cured at 65% relative humidity at 20 ºC. The compressive and flexural tensile strengths, elastic modulus and Poisson's ratio of hardened concrete were measured. Laboratory compressive and tensile strength tests results showed that LWC can be produced by the use of limestone. The aim of this study is twofold: one is to design a lightweight concrete with the use of limestone that will provide an advantage of reduction in dead weight of a structure; and second is to obtain a more economical LWC mixture with the use of limestone.

  12. Influence of limestone fillers on combustion characteristics of asphalt mortar for pavements

    DEFF Research Database (Denmark)

    Ke, Wu; Kai, Zhu; Wu, Hao

    2014-01-01

    Asphalt materials will be ignited and release significant toxic fumes within tunnel fires. Thus, combustion characteristics of asphalt materials used in road tunnel should be studied in order to limit such an adverse effect. In the present work we study the influence of limestone fillers on combu...

  13. Model of fragmentation of limestone particles during thermal shock and calcination in fluidised beds

    Energy Technology Data Exchange (ETDEWEB)

    Saastamoinen, J.; Pikkarainen, T.; Tourunen, A.; Rasanen, M.; Jantti, T. [VTT Technical Research Center, Jyvaskyla (Finland)

    2008-11-15

    Fragmentation of limestone due to thermal shock and calcination in a fluidised bed was studied through experiments and modelling. The time for heating was estimated by model calculations and the time for calcination by measurements. Fragmentation due to thermal shock was carried out by experiments in a CO{sub 2} atmosphere in order to prevent the effect of calcination. It was found to be much less than fragmentation due to calcination. Average particle sizes before and after fragmentation are presented for several types of limestone. The effects of particle size and gas composition on the primary fragmentation were studied through experiments. Increasing the fluidisation velocity increased the tendency to fragment. The evolution of the particle size distribution (PSD) of limestone particles due to thermal shock and during calcination (or simultaneous calcination and sulphation) were calculated using a population balance model. Fragmentation due to thermal shock is treated as an instantaneous process. The fragmentation frequency during calcination is presented as exponentially decaying over time. In addition to the final PSD, this model also predicts the PSD during the calcination process. The fragmentation was practically found to end after 10 min. Furthermore. a population balance method to calculate the particle size distribution and amount of limestone in fluidised beds in dynamic and steady state, when feeding history is known, is presented.

  14. Limestone particle attrition and size distribution in a small circulating fluidized bed

    Energy Technology Data Exchange (ETDEWEB)

    Zhongxiang Chen; John R. Grace; C. Jim Lim [University of British Columbia, Vancouver, BC (Canada). Department of Chemical and Biological Engineering

    2008-06-15

    Limestone particle attrition was investigated in a small circulating fluidized bed reactor at temperatures from 25 to 850{sup o}C, 1 atm pressure and superficial gas velocities from 4.8 to 6.2 m/s. The effects of operating time, superficial gas velocity and temperature were studied with fresh limestone. No calcination or sulfation occurred at temperatures {le} 580{sup o}C, whereas calcination and sulfation affected attrition at 850{sup o}C. Increasing the temperature (while maintaining the same superficial gas velocity) reduced attrition if there was negligible calcination. Attrition was high initially, but after about 24 h, the rate of mass change became constant. The ratio of initial mean particle diameter to that at later times increased linearly with time and with (U{sub g} - U{sub mf}){sup 2}, while decreasing exponentially with temperature, with an activation energy for fresh limestone of -4.3 kJ/mol. The attrition followed Rittinger's surface theory. The change of surface area of limestone particles was proportional to the total excess kinetic energy consumed and to the total attrition time, whereas the change of surface area decreased exponentially with increasing temperature. At 850{sup o}C, the attrition rate of calcined lime was highest, whereas the attrition rate was lowest for sulfated particles. When online impact attrition was introduced, the attrition rate was about an order of magnitude higher than without impacts. 25 refs., 14 figs., 4 tabs.

  15. Performance Monitoring: Evaluating an Organic Carbon-Limestone PRB for Treatment of Heavy Metals and Acidity

    Science.gov (United States)

    Since 2004, researchers from the U.S. EPA National Risk Management Research Laboratory (NRMRL) have annually evaluated performance of an organic carbon-limestone permeable reactive barrier (PRB) system installed in 2003 by EPA Region 6 at the Delatte Metals Superfund site in Ponc...

  16. Attrition of limestones by impact loading in fluidized beds: The influence of reaction conditions

    Energy Technology Data Exchange (ETDEWEB)

    Scala, Fabrizio [Istituto di Ricerche sulla Combustione, Consiglio Nazionale delle Ricerche, Napoli (Italy); Salatino, Piero [Istituto di Ricerche sulla Combustione, Consiglio Nazionale delle Ricerche, Napoli (Italy); Dipartimento di Ingegneria Chimica, Universita degli Studi di Napoli Federico II, Napoli (Italy)

    2010-09-15

    The extent of attrition associated with impact loading was studied for five different limestones pre-processed in fluidized bed under different reaction conditions. The experimental procedure was based on the measurement of the amount and the particle size distribution of the debris generated upon impact of sorbent samples against a target at velocities between 10 and 45 m/s. The effect of calcination, sulfation and calcination/re-carbonation on impact damage was assessed. Fragmentation by impact loading of the limestones was significant and increased with the impact velocity. Lime samples displayed the largest propensity to undergo impact damage, followed by sulfated, re-carbonated and raw limestones. Fragmentation of the sulfated samples followed a pattern typical of the failure of brittle materials. On the other hand, the behaviour of lime samples better conformed to a disintegration failure mode, with extensive generation of very fine fragments. Raw limestone and re-carbonated lime samples followed either of the two patterns depending on the sorbent nature. The extent of particle fragmentation increased after multiple impacts, but the incremental amount of fragments generated upon one impact decreased with the number of successive impacts. (author)

  17. Use of limestone obtained from waste of the mussel cannery industry for the production of mortars

    International Nuclear Information System (INIS)

    Ballester, Paloma; Marmol, Isabel; Morales, Julian; Sanchez, Luis

    2007-01-01

    Various types of cement-SiO 2 -CaCO 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 3 aggregate consists mainly of elongated prismatic particles less than 4 μm long rather than of the rounded particles of smaller size (2-6 μm) 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

  18. Conceptualization of flow and transport in a limestone aquifer by multiple dedicated hydraulic and tracer tests

    DEFF Research Database (Denmark)

    Mosthaf, Klaus; Brauns, Bentje; Fjordbøge, Annika Sidelmann

    2018-01-01

    Limestone aquifers are of great interest as a drinking water resource in many countries. They often have a complex crushed and fractured geology, which makes the analysis and description of flow and transport processes in such aquifers a challenging task. In this study, the solute transport behav...

  19. Lateral capacity of rock sockets in limestone under cyclic and repeated loading.

    Science.gov (United States)

    2010-08-01

    This report contains the results from full scale lateral load testing of two short rock socketed shafts in : limestone, and the development of recommendations for p-y analysis using those results. Two short shafts 42 : inches in diameter were constru...

  20. Effects of limestone petrography and calcite microstructure on OPC clinker raw meals burnability

    Science.gov (United States)

    Galimberti, Matteo; Marinoni, Nicoletta; Della Porta, Giovanna; Marchi, Maurizio; Dapiaggi, Monica

    2017-10-01

    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.

  1. An experimental study on the primary fragmentation and attrition of limestones in a fluidized bed

    International Nuclear Information System (INIS)

    Yao, Xuan; Zhang, Hai; Yang, Hairui; Liu, Qing; Wang, Jinwei; Yue, Guangxi

    2010-01-01

    In this paper, an experimental study on the primary fragmentation and attrition of 5 limestones in a fluidized bed was conducted. The intensity of fragmentation and attrition were measured in the same apparatus but at different fluidizing velocities. It was found that the averaged size of the particles decreased by about 10-20% during the fragmentation process. The important factors for particle comminution include limestone types, heating rate, calcination condition and ambient CO 2 concentration. Fragmentation mainly occurred in the first a few minutes in the fluidized bed and it was more intense than that in the muffle furnace at the same temperature. The original size effect was ambiguous, depending on the limestone type. The comminution caused by attrition mainly occurred during calcination process rather than sulphation process. The sulphation process was fragmentation and attrition resisted. The attrition rate of sulphate was similar to that of lime in trend, decaying exponentially with time, but was one-magnitude-order smaller than that of lime. Present experimental results indicate that fragmentation mechanism of the limestone is dominated by CO 2 release instead of thermal stress. (author)

  2. Piedramuelle Limestone in the building heritage of Oviedo, Spain, and adjacent towns.

    Science.gov (United States)

    Cardenes Van den Eynde, Victor; Mateos, Felix Javier; Valdeon, Luis; Rojo, Araceli

    2017-04-01

    The Piedramuelle limestone has a very important representation in the building heritage of Oviedo, historical capital of Asturias (Spain) and surrounding towns. This argillaceous limestone has been quarried since the High Middle Ages until the beginning of the XX century. The main mineralogical components are carbonates (mainly calcite and sometimes ankerite, 70-90%), quartz (5-15%), terrigenous minerals (6-15%) and iron oxides (blocks and ashlars of the buildings. Some of the buildings constructed with Piedramuelle limestone are the Cathedral, the Old University and the Palaces from the XVII and XVIII centuries. The ambiance and historical architecture of Oviedo and adjacent towns is closely linked with the textures and colors of this stone. Nowadays, the Piedramuelle limestone is not exploited anymore, being the quarries exhausted. This represents an issue from a conservation point of view, since there is not a suitable stone for replacement. In order to preserve and maintain the building heritage of these towns, it is very important to prospect and protect the remaining outcrops still able to supply this characteristic stone.

  3. Effects of phosphate limestone on structure and quality under sugarcane vertisoles

    Directory of Open Access Journals (Sweden)

    Pedro Cairo Cairo

    2017-10-01

    Full Text Available The work was developed in sugarcane areas of cuban vertisols of the north coast of the province of Villa Clara municipality of Sagua la Grande, with the aim of evaluating the effectiveness of phosphate limestone and their combinations with fertilizers and organic manure on the structure and quality of vertisols under sugarcane cultivation. An experiment with phosphate limestone levels and combinations with organic manure (compost, filter cake and fertilizers (NPK was carried out on a wasstrip-block design. A soil analysis was performedat the depth of 0-20 and 20 -40 cm 36 months after the application of treatments. Organic matter, stable aggregates, factor structure, permeability, T value, exchangeable cations, index soil quality and productivity of sugarcane were evaluated. Phosphate limestone and there combinations with organic manures manifested significant effects on soil structure both in the surface layer and subsurface with residual impact over time to 36 months. The results show the close relationship between phosphate limestone and there combinations with organic manures on soil quality index additive, yield of sugarcane and economic impact.

  4. Thermal effects induced by laser ablation in non-homogeneous limestone covered by an impurity layer

    Science.gov (United States)

    Cocean, Alexandru; Pelin, Vasile; Cazacu, Marius Mihai; Cocean, Iuliana; Sandu, Ion; Gurlui, Silviu; Iacomi, Felicia

    2017-12-01

    This paper reports preliminary results concerning thermal effects induced by urban/industrial air pollutants deposited on a limestone rock when heated by pulsed laser in the cleaning process. The process of laser cleaning treatment of the crust is simulated using COMSOL Multiphysics 4.4, finite element analysis software. Scanning Electron Microscopy coupled with Energy Dispersive X-ray Spectroscopy and Laser Induced Breakdown Spectroscopy techniques have been used to analyze the chemical composition of the samples. Two elements found as being present into the dust and in the crust, such as iron and magnesium particles are used for simulation in COMSOL. Therefore, the profiles heat evolutions on the crust surface and inside limestone are obtained as thermal interactions between the three components (iron, magnesium and limestone), simulating the non-homogeneous materials. It has been observed that iron impurities caused by the dust deposition may damage the limestone through a process of overheating, as a consequence of a high thermal conduction phenomenon, recorded for the region with iron impurities and sizes of micrometric order are localized. The thermal contact between the three components results in plots that reflect their thermal interactions.

  5. Radiological significance of Egyptian limestone and alabaster used for construction of dwellings

    International Nuclear Information System (INIS)

    El-Taher, A.; Makhluf, V.

    2011-01-01

    The natural radionuclides in limestone and alabaster found in Assuit Governorate in Upper Egypt have been investigated by passive gamma-ray spectrometry. From the measured γ-ray spectra, specific activities were determined. The measured activity concentrations for these natural radionuclides were compared with the reported data from other countries. The radiation hazard parameters related to the exposure of limestone and alabaster have also been calculated. The obtained results of radium equivalent Raeq, level index Iγr, the external hazard index H ex and absorbed dose rate in limestone (90.44, 0.63, 0.17, 39.94) and (70.86, 0.50, 0.13, 31.55) are lower than the acceptable level 370 Bqkg -1 for radium equivalent Ra eq , 1 for level index Iγr, the external hazard index H e≤ I and 59 (nGy.h -1 ) for absorbed dose rate. So limestone and alabaster can be used as building construction without exceeding the proposed radioactivity criterion level. (author)

  6. 230Th/234U dating of coral limestones and vertical uplift at Djibouti

    International Nuclear Information System (INIS)

    Faure, Hugues; Hoang, C.T.; Lalou, Claude

    1980-01-01

    Coral limestones sampled from marine terraces along the Afar coast have been dated by the 230 Th/ 234 U method. The ages confirm the stratigraphic unity of these formations and the existence of the paleo sea level dated 124 000 years ago in this region. These results permit to deduce the uplift rates of this littoral [fr

  7. Treatment Of Metal-Mine Effluents By Limestone Neutralization And Calcite Co-Precipitation

    Science.gov (United States)

    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...

  8. Treatment Of Metal-Mine Effluents By Limestone Neutralization And Calcite Co-Precipitation (Presentation)

    Science.gov (United States)

    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...

  9. Limestone amendments and the establishment of legumes on pyritic colliery spoil

    Energy Technology Data Exchange (ETDEWEB)

    Jefferies, R A

    1981-11-01

    This paper examines the effect of high liming, using two commercially available limestone grades of different particle size distributions, on the establishment of six contrasting legume species, in order to determine whether other legume species are more tolerant of the conditions imposed by high liming, and whether the effect can be avoided. 13 refs.

  10. Autogenous and drying shrinkage of sodium carbonate activated slag altered by limestone powder incorporation

    NARCIS (Netherlands)

    Yuan, B.; Yu, Q.L.; Dainese, E.; Brouwers, H.J.H.

    2017-01-01

    This paper aims to study the shrinkage mechanism of sodium carbonate activated slag containing limestone powder (LP). The workability, pore structure, reaction kinetics and strength development were characterized. The results show that the autogenous shrinkage increases when the dosage of LP is low

  11. Assessing the chemical involvement of limestone powder in sodium carbonate activated slag

    NARCIS (Netherlands)

    Yuan, B.; Yu, Q.; Brouwers, H.J.H.

    2017-01-01

    This study aims to investigate the effect of limestone powder (LP) on the reaction of sodium carbonate activated slag. The results show that the incorporated LP up to 30% improves the strength development, especially at advanced curing ages. A slightly accelerated reaction is observed for samples

  12. Influence of limestone powder on the reaction kinetics and mechanical properties of sodium carbonate activated slag

    NARCIS (Netherlands)

    Yuan, B.; Yu, Q.; Brouwers, H.J.H.

    2016-01-01

    The effects of limestone powder (LP) on the performance of Portland cement based composites have been extensively studied, considering that LP not only acts as nuclei sites, but that it is also chemically involved in the hydration process, which improves the reaction degree at the early age. In high

  13. Transient Catalytic Activity of Calcined Dolomitic Limestone in a Fluidized Bed during Gasification of Woody Biomass.

    Czech Academy of Sciences Publication Activity Database

    Pohořelý, Michael; Jeremiáš, Michal; Skoblia, S.; Beňo, Z.; Šyc, Michal; Svoboda, Karel

    2016-01-01

    Roč. 30, č. 5 (2016), s. 4065-4071 ISSN 0887-0624 R&D Projects: GA ČR GC14-09692J Institutional support: RVO:67985858 Keywords : fluidized- bed gasification * woody biomass * limestone Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 3.091, year: 2016

  14. Hydrobiogeochemical interactions in 'anoxic' limestone drains for neutralization of acidic mine drainage

    Science.gov (United States)

    Robbins, E.I.; Cravotta, C.A.; Savela, C.E.; Nord, G.L.

    1999-01-01

    Processes affecting neutralization of acidic coal mine drainage were evaluated within 'anoxic' limestone drains (ALDs). Influents had pH???3.5 and dissolved oxygen treatment step is indicated to promote Al removal before diverting acidic mine water into alkalinity-producing materials. ?? 1998 Elsevier Science Ltd.

  15. Extensive yellow crusts below limestone overhangs: a new taxon close to a minute epiphytic lichen

    Czech Academy of Sciences Publication Activity Database

    Vondrák, Jan; Moniri, M. H.; Malíček, Jiří; Košnar, J.

    2017-01-01

    Roč. 35, č. 3 (2017), s. 368-376 ISSN 0107-055X Institutional support: RVO:67985939 Keywords : Caloplaca substerilis * limestone rocks * Central Europe Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany Impact factor: 0.847, year: 2016

  16. Effect of Limestone Powder on Acid Attack Characteristics of Cement Pastes

    Directory of Open Access Journals (Sweden)

    Shuhua LIU

    2014-12-01

    Full Text Available The acid resistance of cement pastes containing limestone powder with two different water-binder (w/b ratios exposed to acetic (pH = 4 and sulfuric acid (pH = 2 solutions respectively were investigated in this paper. Limestone powder, fly ash and silica fume were also added to the cement paste mixture at different proportions. Static and flowing aqueous environments were set in this experiment. Strength and microstructure of the pastes after acid attack were investigated by using strength test, X-ray diffractometer (XRD and scanning electron microscopy (SEM. The experimental results show that the erosion degree depends not only on pH value of the solution and w/b ratio of the pastes, but also on the content of limestone powder. Acetic acid reacts with calcium hydroxide and carbonate thus dissolving the pastes, while sulfuric acid consumed calcium hydroxide, and generated gypsum and ettringite. The consumption of calcium hydroxide in the flowing solution group is higher than that in the static solution because the flowing sulfuric acid solution has negative effect upon the gypsum crystallization. Fly ash and silica fume are beneficial to limestone cement paste because of the less calcium hydroxide formation, which is among the hydrates vulnerable to acid erosion. DOI: http://dx.doi.org/10.5755/j01.ms.20.4.6231

  17. Limestone and Zeolite as Alternative Media in Horizontal Subsurface Flow Constructed Wetlands: Laboratory-Scale Studies

    Science.gov (United States)

    Lizama, K.; Jaque, I.; Ayala, J.

    2016-12-01

    Arsenic is well known for its chronic toxicity. Millions of people around the world are currently at risk, drinking water with As concentrations above 10 ppb, the WHO drinking water guideline. Although different treatment options exist, they are often limited by elevated costs and maintenance requirements. Constructed wetlands are a natural water treatment system, capable to remove metals and metalloids -including As- via different physical, chemical and biological processes. The use of alternative supporting media to enhance As removal in subsurface flow wetlands has been recommended, but not sufficiently studied. Limestone and zeolite have been identified as effective supporting media in subsurface flow wetlands aiming As removal. However, there are still key aspects to be addressed, such as the implications of using these media, the speciation in the solid phase, the role of vegetation, etc. This study investigated the performance of limestone and zeolite in three types of experiments: batch, column and as main supporting media in a bench scale horizontal subsurface flow wetland system. Synthetic water resembling a contaminated river in Chile (As concentration=3 mg/L, Fe concentration= 100 mg/L, pH=2) was used in all experiments. In the batch experiments, the As concentration, the mass of media and the contact time were varied. The column system consisted of three limestone columns and three zeolite columns, operated under a hydraulic loading of 20 mm/d. The wetland system consisted of twelve PVC cells: six filled with zeolite and six with limestone. Phragmites australis were planted in three cells of each media type, as control cells. From the batch experiments, maximum As sorption capacities as indicated by Langmuir model were 1.3 mg/g for limestone and 0.17 mg/g for zeolite, at 18 h contact time and 6.3 g/L medium concentration. EDS and XPS analyses revealed that As and Fe were retained in zeolite at the end of the batch experiments. Zeolite and limestone

  18. Convection in porous media

    CERN Document Server

    Nield, Donald A

    1992-01-01

    This book provides a user-friendly introduction to the topic of convection in porous media The authors as- sume that the reader is familiar with the basic elements of fluid mechanics and heat transfer, but otherwise the book is self-contained The book will be useful both as a review (for reference) and as a tutorial work, suitable as a textbook in a graduate course or seminar The book brings into perspective the voluminous research that has been performed during the last two decades The field has recently exploded because of worldwide concern with issues such as energy self-sufficiency and pollution of the environment Areas of application include the insulation of buildings and equipment, energy storage and recovery, geothermal reservoirs, nuclear waste disposal, chemical reactor engineering, and the storage of heat-generating materials such as grain and coal Geophysical applications range from the flow of groundwater around hot intrusions to the stability of snow against avalanches

  19. Optimized manufacturable porous materials

    DEFF Research Database (Denmark)

    Andreassen, Erik; Andreasen, Casper Schousboe; Jensen, Jakob Søndergaard

    Topology optimization has been used to design two-dimensional material structures with specific elastic properties, but optimized designs of three-dimensional material structures are more scarsely seen. Partly because it requires more computational power, and partly because it is a major challenge...... to include manufacturing constraints in the optimization. This work focuses on incorporating the manufacturability into the optimization procedure, allowing the resulting material structure to be manufactured directly using rapid manufacturing techniques, such as selective laser melting/sintering (SLM....../S). The available manufacturing methods are best suited for porous materials (one constituent and void), but the optimization procedure can easily include more constituents. The elasticity tensor is found from one unit cell using the homogenization method together with a standard finite element (FE) discretization...

  20. Filtration in Porous Media

    DEFF Research Database (Denmark)

    Yuan, Hao; Shapiro, Alexander

    There is a considerable and ongoing effort aimed at understanding the transport and the deposition of suspended particles in porous media, especially non-Fickian transport and non-exponential deposition of particles. In this work, the influential parameters in filtration models are studied...... to understand their effects on the non-Fickian transport and the non-exponential deposition. The filtration models are validated by the comparisons between the modelling results and the experimental data.The elliptic equation with distributed filtration coefficients may be applied to model non-Fickian transport...... and hyperexponential deposition. The filtration model accounting for the migration of surface associated particles may be applied for non-monotonic deposition....

  1. Biogenic Cracks in Porous Rock

    Science.gov (United States)

    Hemmerle, A.; Hartung, J.; Hallatschek, O.; Goehring, L.; Herminghaus, S.

    2014-12-01

    Microorganisms growing on and inside porous rock may fracture it by various processes. Some of the mechanisms of biofouling and bioweathering are today identified and partially understood but most emphasis is on chemical weathering, while mechanical contributions have been neglected. However, as demonstrated by the perseverance of a seed germinating and cracking up a concrete block, the turgor pressure of living organisms can be very significant. Here, we present results of a systematic study of the effects of the mechanical forces of growing microbial populations on the weathering of porous media. We designed a model porous medium made of glass beads held together by polydimethylsiloxane (PDMS), a curable polymer. The rheological properties of the porous medium, whose shape and size are tunable, can be controlled by the ratio of crosslinker to base used in the PDMS (see Fig. 1). Glass and PDMS being inert to most chemicals, we are able to focus on the mechanical processes of biodeterioration, excluding any chemical weathering. Inspired by recent measurements of the high pressure (~0.5 Mpa) exerted by a growing population of yeasts trapped in a microfluidic device, we show that yeast cells can be cultured homogeneously within porous medium until saturation of the porous space. We investigate then the effects of such an inner pressure on the mechanical properties of the sample. Using the same model system, we study also the complex interplay between biofilms and porous media. We focus in particular on the effects of pore size on the penetration of the biofilm within the porous sample, and on the resulting deformations of the matrix, opening new perspectives into the understanding of life in complex geometry. Figure 1. Left : cell culture growing in a model porous medium. The white spheres represent the grains, bonds are displayed in grey, and microbes in green. Right: microscopy picture of glass beads linked by PDMS bridges, scale bar: 100 μm.

  2. The Öland limestone - A Swedish stone used for more than one thousand years

    Science.gov (United States)

    Schouenborg, Björn; Wickström, Linda; Mikaelsson, Jan

    2016-04-01

    The second largest island in Sweden is the home of the "Öland limestone", a condensed and bedded limestone whose origin dates back to Lower Ordovician, i.e. about 480 M years ago. Öland is a part of the palaeocontinent Baltica that, at the time, was situated at low latitudes with deposition of the calcareous sediments in a cool water environment. The limestone on Öland represents a proximal ramp tectonic setting, with the oldest sediments deposited in the west and younger sediments deposited towards east and southeast. Fluctuating sea-levels have created erosional hard grounds such as the Flowery sheet. These hardgrounds are recognised by their vivid colours and trace fossils, and can be traced all over Baltica, but is maybe best represented on Öland. Ordovician limestones are present in many places in Sweden, but it is the occurrence on Öland that is the most renowned in a building stone perspective. One reason for this is the favourable trading location, an island off the Swedish East coast in middle of the trading routes between the Baltic countries and the continent. Other reasons are the pleasant aesthetical values with numerous orthoceratites and other fossils. The limestones on Öland differ in colour. From the red varieties (with oxidized iron) to brownish and grey. The bedding is mostly in the cm-scale which easily enables very exploitable thickness of slabs. Every mm limestone represents about 1000 years of deposition. The limestone has most likely been used in a very crude way for many thousand years, but archaeological evidence of a more industrialized usage is just a little more than 1000 years. It is known from the literature that the first official Swedish king, Gustav Vasa (16th century), desired this stone. At the time it was called "Öland marble", and the king "imported" specialists to process it further at the Royal Stone workshop on northern Öland. Remnants of tools and working sites still remain in an outdoor museum. Export of the

  3. Luminescence of porous silicon doped by erbium

    International Nuclear Information System (INIS)

    Bondarenko, V.P.; Vorozov, N.N.; Dolgij, L.N.; Dorofeev, A.M.; Kazyuchits, N.M.; Leshok, A.A.; Troyanova, G.N.

    1996-01-01

    The possibility of the 1.54 μm intensive luminescence in the silicon dense porous layers, doped by erbium, with various structures is shown. Low-porous materials of both porous type on the p-type silicon and porous silicon with wood-like structure on the n + type silicon may be used for formation of light-emitting structures

  4. Morphological Changes of Limestone Sorbent Particles during Carbonation/Calcination Looping Cycles in a Thermogravimetric Analyzer (TGA) and Reactivation with Steam

    KAUST Repository

    Wu, Y.; Blamey, J.; Anthony, E. J.; Fennell, P. S.

    2010-01-01

    Carbonation and calcination looping cycles were carried out on four limestones in a thermogravimetric analyzer (TGA). The CO2 carrying capacity of a limestone particle decays very quickly in the first 10 cycles, reducing to about 20% of its original

  5. Porous media geometry and transports

    CERN Document Server

    Adler, Pierre

    1992-01-01

    The goal of ""Porous Media: Geometry and Transports"" is to provide the basis of a rational and modern approach to porous media. This book emphasizes several geometrical structures (spatially periodic, fractal, and random to reconstructed) and the three major single-phase transports (diffusion, convection, and Taylor dispersion).""Porous Media"" serves various purposes. For students it introduces basic information on structure and transports. Engineers will find this book useful as a readily accessible assemblage of al the major experimental results pertaining to single-phase tr

  6. Comparison of Limestone and Ground Fish for Treatment of Nutritional Rickets in Children in Nigeria.

    Science.gov (United States)

    Thacher, Tom D; Bommersbach, Tanner J; Pettifor, John M; Isichei, Christian O; Fischer, Philip R

    2015-07-01

    To determine whether children with calcium-deficiency rickets respond better to treatment with calcium as limestone or as ground fish. Nigerian children with active rickets (n = 96) were randomized to receive calcium as powdered limestone (920 mg of elemental calcium) or ground fish (952 mg of elemental calcium) daily for 24 weeks. Radiographic healing was defined as achieving a score of 1.5 or less on a 10-point scale. The median (range) age of enrolled children was 35 (6-151) months. Of the 88 children who completed the study, 29 (66%) in the ground fish group and 24 (55%) in the limestone group achieved the primary outcome of a radiographic score of 1.5 or less within 6 months (P = .39). The mean radiographic score improved from 6.2 ± 2.4 to 1.8 ± 2.2 in the ground fish group and from 6.3 ± 2.2 to 2.1 ± 2.4 in the limestone group (P = .68 for group comparison). In an intention to treat analysis adjusted for baseline radiographic score, age, milk calcium intake, and serum 25-hydroxyvitamin D concentration, the response to treatment did not differ between the 2 groups (P = .39). Younger age was associated with more complete radiographic healing in the adjusted model (aOR 0.74 [95% CI 0.57-0.92]). After 24 weeks of treatment, serum alkaline phosphatase had decreased, calcium and 25-hydroxyvitamin D increased, and bone mineral density increased in both groups, without significant differences between treatment groups. In children with calcium-deficiency rickets, treatment with calcium as either ground fish or limestone for 6 months healed rickets in the majority of children. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  7. Contemporary French Fiction In and Out of Screens

    Directory of Open Access Journals (Sweden)

    Eliane DalMolin

    2012-01-01

    Full Text Available This essay explores the ways in which the widespread craze for reality TV has now extended its contamination to the comparatively more traditional discipline of literature. Today, there is no use denying that, acknowledging, and internalizing, the American domination in the creation of reality shows, French television has followed suit and, as a result of the cultural flooding of such a model, recent French literature has also been swayed by the empire of television in general, and the power of reality TV in particular. The author delineates the increasingly porous frontier separating and conjoining reality TV and literary representation, questions the adoption and consecration of banality as the basic principle of this porosity, and examines the consequences of such a sustained exposure to images of a trite reality on the quality of traditional cultural artifacts such as books. Among other aspects of this transfer, the essay focuses on the effect of the strange and voyeuristic interdependence of cameras, men and their plain reality. Ultimately, the essay wonders why, in all forms of cultural representation, high or low, a spectacle of great banality has now been elevated to the rank of acclaimed cultural production.

  8. The relationship of French people with energy

    International Nuclear Information System (INIS)

    Levy, Jean-Daniel; Potereau, Julien; Gautier, Antoine

    2017-12-01

    This Power Point document presents graphs and tables containing results of a survey performed on the relationship French people have with energy. After a presentation of the survey methodology, it addresses how France commitment in the struggle against climate change is perceived (French people think that their country could do better), which perceptions French people have of stakes and of the French energy policy (the management of the energy issue is perceived as perfectible, and French people have a positive view on energy transition and on the development of renewable energies), and which investments French people stand for (French people are in favour of a more important role of Europe and of citizen cooperatives in the field of energy)

  9. French Prime Minister tours CERN

    CERN Multimedia

    Anaïs Schaeffer

    2012-01-01

    On 30 July, Jean-Marc Ayrault, the Prime Minister of the French Republic, and Geneviève Fioraso, the Minister of Higher Education and Research, visited the Laboratory.   After being met by the Director-General at LHC Point 5, they visited the CMS control centre and experiment cavern, and got a glimpse of the LHC tunnel at Point 5. The visit ended with a round-table discussion with French and other international members of CERN’s scientific community. During the discussion, the Prime Minister reaffirmed that “support for fundamental research has to be maintained, and France must continue to invest in education, research and innovation.” He also paid tribute to CERN's role in international cooperation, which he qualified as “a fine example of science without borders.”

  10. French people and energy issues

    International Nuclear Information System (INIS)

    Chesnais, L.

    2006-01-01

    An opinion poll made in France in 2006 shows that: - French people backs nuclear energy with a slight margin (45% versus 42%), - French people agrees with the electricity production policy led by the government, - about 4 people out of 10 expect a sharp increase in prices concerning car fuels, natural gas and heating fuels in a near future, on the other hand fewer people than in previous years are expecting a price rise for electricity. In this article some figures concerning the consumption of energy in France are given: - 230.000 jobs are directly or indirectly involved in the energy sector, this sector represents 5% of all investment, - a total bill of 24 milliard euros for the energy imports, and - energy spending represents 7.6% of the household budget. (A.C.)

  11. Venus transits - A French view

    Science.gov (United States)

    Débarbat, Suzanne

    2005-04-01

    After a careful study of Mars observations obtained by Tycho Brahé (1546-1601), Kepler (1571-1630) discovered the now-called Kepler's third law. In 1627 he published his famous Tabulae Rudolphinae, a homage to his protector Rudolph II (1552-1612), tables (Kepler 1609, 1627) from which he predicted Mercury and Venus transits over the Sun. In 1629 Kepler published his Admonitio ad Astronomos Advertisement to Astronomers (Kepler 1630), Avertissement aux Astronomes in French Au sujet de phénomènes rares et étonnants de l'an 1631: l'incursion de Vénus et de Mercure sur le Soleil. This was the beginning of the interest of French astronomers, among many others, in such transits, mostly for Venus, the subject of this paper in which dates are given in the Gregorian calendar.

  12. French people and nuclear wastes

    International Nuclear Information System (INIS)

    D'Iribarne, Ph.

    2005-01-01

    On March 21, 2005, the French minister of industry gave to the author of this document, the mission to shade a sociological light on the radioactive wastes perception by French people. The objective of this study was to supply an additional information before the laying down in 2006 of the decisions about the management of high-level and long-lived radioactive wastes. This inquiry, carried out between April 2004 and March 2005, stresses on the knowledge and doubts of the questioned people, on the vision they have of radioactive wastes and of their hazards, and on their opinion about the actors in concern (experts, nuclear companies, government, anti-nuclear groups, public). The last two parts of the report consider the different ways of waste management under study today, and the differences between the opinion of people living close to the Bure site and the opinion of people living in other regions. (J.S.)

  13. New french uranium mineral species

    International Nuclear Information System (INIS)

    Branche, G.; Chervet, J.; Guillemin, C.

    1952-01-01

    In this work, the authors study the french new uranium minerals: parsonsite and renardite, hydrated phosphates of lead and uranium; kasolite: silicate hydrated of uranium and lead uranopilite: sulphate of uranium hydrated; bayleyite: carbonate of uranium and of hydrated magnesium; β uranolite: silicate of uranium and of calcium hydrated. For all these minerals, the authors give the crystallographic, optic characters, and the quantitative chemical analyses. On the other hand, the following species, very rare in the french lodgings, didn't permit to do quantitative analyses. These are: the lanthinite: hydrated uranate oxide; the α uranotile: silicate of uranium and of calcium hydrated; the bassetite: uranium phosphate and of hydrated iron; the hosphuranylite: hydrated uranium phosphate; the becquerelite: hydrated uranium oxide; the curite: oxide of uranium and lead hydrated. Finally, the authors present at the end of this survey a primary mineral: the brannerite, complex of uranium titanate. (author) [fr

  14. French concepts of ''passive safety''

    International Nuclear Information System (INIS)

    Dennielou, Y.; Serret, M.

    1990-01-01

    N 4 model, the French 1400 MW PWR of the 90's, exhibits many advanced features. As far as safety is concerned, the fully computerized control room design takes advantage of the operating experience feedback and largely improves the man machine interface. New post-accident procedures have been developed (the so-called ''physical states oriented procedures''). A complete consistent set of ''Fundamental Safety Rules'' have been issued. This however doesn't imply any significant modification of standard PWR with regard to the passive aspects of safety systems or functions. Nevertheless, traditional PWR safety systems largely use passive aspects: natural circulation, reactivity coefficients, gravity driven control rods, injection accumulators, so on. Moreover, probability calculations allow for comparison between the respective contributions of passive and of active failures. In the near future, eventual options of future French PWRs to be commissioned after 2000 will be evaluated; simplification, passive and forgiving aspects of safety systems will be thoroughly considered. (author)

  15. Reminder: Swiss and French cards

    CERN Multimedia

    2012-01-01

    Communication from the HR Department to members of personnel holding an employment or association contract, above 50% and for more than 3 months, with the Organization. The HR Department would like to remind all members of personnel concerned that they are obliged to: • hold a valid Swiss  Légitimation card AND a valid French card (“Titre de séjour spécial” or “attestation de fonctions”) at all times during the exercise of their functions in the Organization; • return these documents as soon as their functions in the Organization cease. Not following these rules could be prejudicial to the Organization and appropriate measures may be taken towards the member of personnel concerned. Information and procedures concerning Swiss and French cards (first application, renewal, theft/loss, etc.) are available in the Admin e-guide. Users and Unpaid Associates must contact the Users Office HR Department Tel.: 729...

  16. Swiss and French cards - Reminder

    CERN Multimedia

    HR Department

    2011-01-01

    Communication from the HR Department to members of personnel holding an employment or association contract, above 50% and for more than 3 months, with the Organization. The HR Department would like to remind all members of the personnel concerned that they are obliged to: hold a valid Swiss Légitimation card AND a valid French card (“Titre de séjour spécial” or “attestation de fonctions”) at all times during the exercise of their functions in the Organization; return these documents as soon as their functions in the Organization cease. Not following these rules could be prejudicial to the Organization and appropriate measures may be taken with respect to the member of the personnel concerned. Information and procedures concerning Swiss and French cards (first application, renewal, theft/loss, etc.) are available in the Admin e-guide: https://cern.ch/admin-eguide/cartes/proc_cartes_home.asp Users and Unpaid Associates must ...

  17. PWR standardization: The French experience

    International Nuclear Information System (INIS)

    Bacher, P.E.

    1987-01-01

    After a short historical review of the French PWR programme with 45000 MWe in operation and 15000 MWe under construction, the paper first develops the objectives and limits of the standardizatoin policy. Implementation of standardization is described through successive reactor series and feedback of experience, together with its impact on safety and on codes and standards. Present benefits of standardization range from low engineering costs to low backfitting costs, via higher quality, reduction in construction times and start-up schedules and improved training of operators. The future of the French programme into the 1990's is again with an advanced standardized series, the N4-1400 MW plant. There is no doubt that the very positive experience with standardization is relevant to any country trying to achieve self-reliance in the nuclear power field. (author)

  18. Hydrodynamic dispersion within porous biofilms

    KAUST Repository

    Davit, Y.; Byrne, H.; Osborne, J.; Pitt-Francis, J.; Gavaghan, D.; Quintard, M.

    2013-01-01

    Many microorganisms live within surface-associated consortia, termed biofilms, that can form intricate porous structures interspersed with a network of fluid channels. In such systems, transport phenomena, including flow and advection, regulate

  19. Vibrational modes of porous silicon

    International Nuclear Information System (INIS)

    Sabra, M.; Naddaf, M.

    2012-01-01

    On the basis of theoretical and experimental investigations, the origin of room temperature photoluminescence (PL) from porous silicon is found to related to chemical complexes constituted the surface, in particular, SiHx, SiOx and SiOH groups. Ab initio atomic and molecular electronic structure calculations on select siloxane compounds were used for imitation of infrared (IR) spectra of porous silicon. These are compared to the IR spectra of porous silicon recorded by using Fourier Transform Infrared Spectroscopy (FTIR). In contrast to linear siloxane, the suggested circular siloxane terminated with linear siloxane structure is found to well-imitate the experimental spectra. These results are augmented with EDX (energy dispersive x-ray spectroscopy) measurements, which showed that the increase of SiOx content in porous silicon due to rapid oxidation process results in considerable decrease in PL peak intensity and a blue shift in the peak position. (author)

  20. Transport phenomena in porous media

    CERN Document Server

    Ingham, Derek B

    1998-01-01

    Research into thermal convection in porous media has substantially increased during recent years due to its numerous practical applications. These problems have attracted the attention of industrialists, engineers and scientists from many very diversified disciplines, such as applied mathematics, chemical, civil, environmental, mechanical and nuclear engineering, geothermal physics and food science. Thus, there is a wealth of information now available on convective processes in porous media and it is therefore appropriate and timely to undertake a new critical evaluation of this contemporary information. Transport Phenomena in Porous Media contains 17 chapters and represents the collective work of 27 of the world's leading experts, from 12 countries, in heat transfer in porous media. The recent intensive research in this area has substantially raised the expectations for numerous new practical applications and this makes the book a most timely addition to the existing literature. It includes recent major deve...

  1. Positronium chemistry in porous materials

    International Nuclear Information System (INIS)

    Kobayashi, Y.; Ito, K.; Oka, T.; Hirata, K.

    2007-01-01

    Porous materials have fascinated positron and positronium chemists for over decades. In the early 1970s it was already known that ortho-positronium (o-Ps) exhibits characteristic long lifetimes in silica gels, porous glass and zeolites. Since then, our understanding of Ps formation, diffusion and annihilation has been drastically deepened. Ps is now well recognized as a powerful porosimetric and chemical probe to study the average pore size, pore size distribution, pore connectivity and surface properties of various porous materials including thin films. In this paper, developments of Ps chemistry in porous materials undertaken in the past some 40 yr are surveyed and problems to be addressed in future are briefly discussed

  2. Porous substrates filled with nanomaterials

    Science.gov (United States)

    Worsley, Marcus A.; Baumann, Theodore F.; Satcher, Jr., Joe H.; Stadermann, Michael

    2018-04-03

    A composition comprising: at least one porous carbon monolith, such as a carbon aerogel, comprising internal pores, and at least one nanomaterial, such as carbon nanotubes, disposed uniformly throughout the internal pores. The nanomaterial can be disposed in the middle of the monolith. In addition, a method for making a monolithic solid with both high surface area and good bulk electrical conductivity is provided. A porous substrate having a thickness of 100 microns or more and comprising macropores throughout its thickness is prepared. At least one catalyst is deposited inside the porous substrate. Subsequently, chemical vapor deposition is used to uniformly deposit a nanomaterial in the macropores throughout the thickness of the porous substrate. Applications include electrical energy storage, such as batteries and capacitors, and hydrogen storage.

  3. New Abbreviations in Colloquial French

    Directory of Open Access Journals (Sweden)

    Vladimir Pogačnik

    2015-12-01

    Full Text Available The author of the article treats the process of abbreviations, which he explored forty years ago in his master thesis. The article is based on the corpus created on the basis of Télématin broadcast on French television network TV5. According to the author, clipping is a widespread process that occurs primarily in various forms of oral communication.

  4. The French natural gas industry

    International Nuclear Information System (INIS)

    1999-01-01

    This little folder summarizes in few pages the main economical data of the French natural gas industry: supplies according to the country of origin, length of transport and distribution networks, LNG tanker ship fleet, underground storage capacity, population of LNG-fueled vehicles, cogeneration installations, consumption by sectors and by industrial activities, LPG consumption, supplies, distribution and sales, LPG-fuel for vehicles, CO 2 and NO x releases, equipment of households. (J.S.)

  5. Food studies in French History

    DEFF Research Database (Denmark)

    Hedegaard, Liselotte

    The overarching question of this paper is whether it is possible to identify concepts that define a specifically French tradition regarding food. Two themes seem central. The first theme is the relationship between food and place as it emerges in concepts such as authenticity and terroir....... The second theme is the "how" food is eaten and can be studied through concepts such as commensality, synchronisation and structure...

  6. The French deterrence from 1945

    International Nuclear Information System (INIS)

    Bouchard, J.

    1997-01-01

    Here is presented a particular lighting of deterrence history, by sciences and technologies which have allowed their creation and development. Accompanying the historical evolution of the French deterrence forces during the first phase of these sciences constitution, these sciences and technologies are at the base of the nuclear weapons conception, but they also contributed to the realization of the industrial building and to a doctrine constitution. (N.C.)

  7. Rare earth element and strontium isotopic study of seamount-type limestones in Mesozoic accretionary complex of Southern Chichibu Terrane, central Japan. Implication for incorporation process of seawater REE into limestones

    International Nuclear Information System (INIS)

    Tanaka, Kazuya; Miura, Noriko; Asahara, Yoshihiro; Kawabe, Iwao

    2003-01-01

    Ishimaki and Tahara limestones occur as exotic blocks juxtaposed in the Mesozoic (Jurassic) accretionary complex of Southern Chichibu Terrane in eastern Aichi Prefecture, central Japan. They are supposed to be of the seamount-type limestone, since they have no terrigenous materials and are intimately associated with greenstones. REE (rare earth elements) and Sr isotopic studies for the limestones have been made in order to know their geochemical characteristics, ages and origins. Their 87 Sr/ 86 Sr ratios, when referred to the seawater 87 Sr/ 86 Sr curve and relevant geological data, suggest that Ishimaki and Tahara limestones are the late Permian and the Carboniferous to the Early Permian, respectively. Two greenstone fragments found inside the Ishimaki limestone block and one greenstone sample associated with Tahara limestone block, resemble the Hawaiian alkali basalt in the their REE and Y patterns. This is supporting the idea that the limestone blocks may be parts of reef limestones on ancient volcanic seamounts. All the limestone samples, except three unusual Tahara ones, show seawater REE and Y signatures in their chondrite-normalized patterns. Their REE/Ca ratios, however, are 10 2 -10 4 times as high as those ratios of modern biogenic carbonates like corals and the seawater. Accordingly, seawater REE and Y were incorporated into the limestones, when originally biogenic carbonates transformed into inorganic calcite and its secondary growths occurred in diagenesis in contact with sufficient seawater. This view is favored by the reported REE partition experiment between calcite overgrowths and seawater solution. The seawater Ce anomaly as a function of water depth in the modern ocean is a key to infer the water depth of the REE and Y incorporation. The Ce anomalies given by log (Ce/Ce*) for about a half of Ishimaki samples and most of Tahara ones are between -0.5 and -0.2, which are compatible with the shallow water origin. Another half of Ishimaki samples

  8. French opinion on Nuclear Energy

    International Nuclear Information System (INIS)

    Bucaille, A.

    2003-01-01

    Contrary to what many think or say, most French people do not have a clear-cut opinion about nuclear power. And until public opinion can be accurately assessed, we should be worried of speaking on its behalf. More than half the population of France believes that nuclear power is the cheapest option, but 40% of them have no idea what the situation really is. The French are keenly aware of the what is at stake at the international level, and the fact that energy is becoming a worldwide issue. What they are most concerned about is nuclear waste and the possibility of a catastrophe of the Chernobyl type occurring. Disquiet about the first is now dissipating, after having increased. But attitudes about the second are ambivalent. A quarter of the French are very ignorant about radioactivity. 20% of the population complain that not enough information is forthcoming, particularly as concerns advances in technology. As can be anticipated, awareness of the question of climate change is growing year by year, with increased reporting of storms, floods and heat waves

  9. Groundwater monitoring of an open-pit limestone quarry: groundwater characteristics, evolution and their connections to rock slopes.

    Science.gov (United States)

    Eang, Khy Eam; Igarashi, Toshifumi; Fujinaga, Ryota; Kondo, Megumi; Tabelin, Carlito Baltazar

    2018-03-06

    Groundwater flow and its geochemical evolution in mines are important not only in the study of contaminant migration but also in the effective planning of excavation. The effects of groundwater on the stability of rock slopes and other mine constructions especially in limestone quarries are crucial because calcite, the major mineral component of limestone, is moderately soluble in water. In this study, evolution of groundwater in a limestone quarry located in Chichibu city was monitored to understand the geochemical processes occurring within the rock strata of the quarry and changes in the chemistry of groundwater, which suggests zones of deformations that may affect the stability of rock slopes. There are three distinct geological formations in the quarry: limestone layer, interbedded layer of limestone and slaty greenstone, and slaty greenstone layer as basement rock. Although the hydrochemical facies of all groundwater samples were Ca-HCO 3 type water, changes in the geochemical properties of groundwater from the three geological formations were observed. In particular, significant changes in the chemical properties of several groundwater samples along the interbedded layer were observed, which could be attributed to the mixing of groundwater from the limestone and slaty greenstone layers. On the rainy day, the concentrations of Ca 2+ and HCO 3 - in the groundwater fluctuated notably, and the groundwater flowing along the interbedded layer was dominated by groundwater from the limestone layer. These suggest that groundwater along the interbedded layer may affect the stability of rock slopes.

  10. Dynamic responses of photosystem II in the Namib Desert shrub, Zygophyllum prismatocarpum, during and after foliar deposition of limestone dust

    International Nuclear Information System (INIS)

    Heerden, P.D.R. van; Krueger, G.H.J.; Kilbourn Louw, M.

    2007-01-01

    The effects of limestone dust deposition on vegetation in desert ecosystems have not yet been reported. We investigated these effects in a succulent shrub from the Namib Desert at a limestone quarry near Skorpion Zinc mine (Namibia). Effects of limestone dust were determined in Zygophyllum prismatocarpum (dollar bush) plants with heavy, moderate and no visible foliar dust cover by means of chlorophyll a fluorescence measurements. Limestone dust deposition decreased overall plant performance through loss of chlorophyll content, inhibition of CO 2 assimilation, uncoupling of the oxygen-evolving complex and decreased electron transport. Importantly, dynamic recovery occurred after termination of limestone extraction at the quarry. Recovery was accelerated by rainfall, mainly because of dust removal from leaves and stimulation of new growth. These results indicate that limestone dust has severe effects on photosynthesis in desert shrubs, but that recovery is possible and that, in arid environments, this process is modulated by rainfall. - Limestone dust deposition reduced photosynthetic capacity in the Namib Desert shrub, Zygophyllum prismatocarpum

  11. Effects of dietary calcium levels and limestone particicle size on the performance, tibia and blood of laying hens

    Directory of Open Access Journals (Sweden)

    K Pelicia

    2011-03-01

    Full Text Available A total of 405 23-week-old ISA® Brown layers were distributed in a completely randomized experimental design in a factorial arrangement with nine treatments consisting of three dietary calcium levels (3.5, 3.75, and 4.5% and three limestone particle sizes (100% fine limestone (FL, 70% FL + 30% coarse limestone (CL and 50% (FL + 50% (CL, with nine replicates of five birds per cage. The following parameters were evaluated: percentage of lay, defective eggs, egg weight, egg mass, feed intake, feed conversion ratio (per kg eggs and per dozen eggs, and mortality. Dietary Ca levels significantly affected lay, with birds fed diets containing 4.5% calcium producing less eggs as compared to those fed 3.0 and 3.75% Ca. Egg production linearly decreased as dietary Ca levels increased, but blood Ca levels (mg/L increased in 28-week-old birds. The interaction of dietary Ca levels and limestone particle sizes resulted in a reduction in tibial ash Ca content as dietary Ca levels increased and as fine limestone was replaced by coarse limestone. It is concluded that a dietary Ca level of 3.75% and 100% fine particle limestone are required to maintain adequate egg production and available Ca blood level.

  12. Cretaceous planktic foraminiferal biostratigraphy of the Calera Limestone, Northern California, USA

    Science.gov (United States)

    Sliter, W.V.

    1999-01-01

    The Calera Limestone is the largest, most stratigraphically extensive limestone unit of oceanic character included in the Franciscan Complex of northern California. The aim of this paper is to place the Calera Limestone at its type locality (Rockaway Beach, Pacifica) in a high-resolution biostratigraphy utilizing planktic foraminifers studied in thin section. A section, about 110 m-thick, was measured from the middle thrust slice exposed by quarrying on the southwest side of Calera Hill at Pacifica Quarry. Lithologically, the section is divided in two units; a lower unit with 73 m of black to dark-grey limestone, black chert and tuff, and an upper unit with 36.8 m of light-grey limestone and medium-grey chert. Two prominent black-shale layers rich in organic carbon occur 11 m below the top of the lower black unit and at the boundary with overlying light-grey unit, yielding a total organic content (TOC) of 4.7% and 1.8% t.w., respectively. The fossiliferous Calera Limestone section measured at Pacifica Quarry, from the lower black shale, contains eleven zones and three subzones that span approximately 26 m.y. from the early Aptian to the late Cenomanian. The zones indentified range from the Globigerinelloides blowi Zone to the Dicarinella algeriana Subzone of the Rotalipora cushmani Zone. Within this biostratigraphic interval, the Ticinella bejaouaensis and Hedbergella planispira Zones at the Aptian/Albian boundary are missing as are the Rotalipora subticinensis Subzone of the Biticinella breggiensis Zone and the overlying Rotalipora ticinensis Zone in the late Albian owing both to low-angle thrust faulting and to unconformities. The abundance and preservation of planktic foraminifers are poor in the lower part and improve only within the upper G. algerianus Zone. The faunal relationship indicate that the lower black shale occurs in the upper part of the G. blowi Zone and correlates with the Selli Event recognized at global scale in the early Aptian. The upper black

  13. Lithofacies palaeogeography and biostratigraphy of the lowermost horizons of the Middle Triassic Hallstatt Limestones (Argolis Peninsula, Greece

    Directory of Open Access Journals (Sweden)

    Fotini A. Pomoni

    2013-07-01

    Taking into consideration the present location of the Hallstatt Formation, in the context of the Hellenides, an area suitable for the deposition of the Hallstatt Limestones, should be located between the sub-Pelagonian (western part of the Pelagonian zone and Pindos geotectonic zones, which during the Triassic corresponded to a platform slope and a deep ocean, respectively. The widespread Middle Triassic Han Bulog Limestones (ammonoid-bearing pelagic limestones from Triassic successions of the Eastern Alps (Dinarides, Hellenides may have formed partly in similar slope environments.

  14. Holothurian sclerites and conodonts in the Upper Carnian (Tuvalian and Norian Limestones in the Central Kanmik Alps

    Directory of Open Access Journals (Sweden)

    Anton Ramovš

    1992-12-01

    Full Text Available Near Bivouac under the Skuta Mountain (locality 1 in the central Kamnik Alps Upper Carnian Limestones were determined with conodont Epigondolella nodosa Hayashi, holothurian sclerites Calclamnella consona Mostler and C. regularis Stefanov, ammonites and other fossils similar to deeper marine Hallstatt facies of Northern Limestone Alps.Conodonts Epigondolella abneptis (Huckriede and very rich holothurian fauna proved the Norian age for bedded limestones with very frequent large chert nodules on the south slope of the Skuta and on Sleme (loc. 2 and 3. They representdeeper marine facies and a distinct development of the Lower Norian

  15. A POROUS, LAYERED HELIOPAUSE

    Energy Technology Data Exchange (ETDEWEB)

    Swisdak, M.; Drake, J. F. [Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, MD 20742 (United States); Opher, M., E-mail: swisdak@umd.edu, E-mail: drake@umd.edu, E-mail: mopher@bu.edu [Department of Astronomy, Boston University, 725 Commonwealth Avenue, Boston, MA 02215 (United States)

    2013-09-01

    The picture of the heliopause (HP)-the boundary between the domains of the Sun and the local interstellar medium (LISM)-as a pristine interface with a large rotation in the magnetic field fails to describe recent Voyager 1 (V1) data. Magnetohydrodynamic (MHD) simulations of the global heliosphere reveal that the rotation angle of the magnetic field across the HP at V1 is small. Particle-in-cell simulations, based on cuts through the MHD model at V1's location, suggest that the sectored region of the heliosheath (HS) produces large-scale magnetic islands that reconnect with the interstellar magnetic field while mixing LISM and HS plasma. Cuts across the simulation reveal multiple, anti-correlated jumps in the number densities of LISM and HS particles, similar to those observed, at the magnetic separatrices. A model is presented, based on both the observations and simulations, of the HP as a porous, multi-layered structure threaded by magnetic fields. This model further suggests that contrary to the conclusions of recent papers, V1 has already crossed the HP.

  16. Fault architecture and growth in clay-limestone alternations: insights from field observations in the SE Basin, France

    International Nuclear Information System (INIS)

    Rocher, M.; Roche, V.; Homberg, C.

    2012-01-01

    Document available in extended abstract form only. The Callovo-Oxfordian (COX) clayey formation is currently studied by Andra in 'Meuse/Haute- Marne' (MHM), eastern Paris basin (France), for hosting a disposal of high level and intermediate, long-lived radioactive waste. As an independent organisation performing safety reviews for the Nuclear Safety Authority, IRSN conducts studies in support of the review of this disposal project. This nearly 130 m-thick clayey formation is surrounded by two 250 m-thick limestone formations. In such limestone/clay alternations, tectonic fracturing is often observed within limestones and propagates in some cases to clay layers. Such a propagation through the COX within or close to the disposal area could diminish its containment ability by creating preferential pathways of radioactive solute towards limestones. Nevertheless, minor to moderate fracturing is difficult to investigate in hectometre scale multilayer systems such as COX: seismic reflexion surveys only provide data on major faults, drilling data are too localised and clays have a 'bad-land' aspect at surface. The aim of this study is to provide a model of fracturing across clay-limestone alternations so as to strengthen the assessment of their possible development. We thus investigated fracturing within decametre-sized clay-limestone alternations, located in the South-Eastern Basin (France), to determine the evolution of fault architecture during its growth. After analysis of the possible scale effects using data from other analogous fields, an application to the COX in MHM is presented. We studied minor normal faults that reflect various stages of development, from simple fault planes restricted to limestones to complex fault zones propagated across several clay-limestone layers. The analysis of the fault characteristics, the construction of displacement profiles and the results obtained using numerical models enlighten fault growth processes, i.e. nucleation

  17. A composite sphere assemblage model for porous oolitic rocks: Application to thermal conductivity

    Directory of Open Access Journals (Sweden)

    F. Chen

    2017-02-01

    Full Text Available The present work is devoted to the determination of linear effective thermal conductivity of porous rocks characterized by an assemblage of grains (oolites coated by a matrix. Two distinct classes of pores, i.e. micropores or intra oolitic pores (oolite porosity and mesopores or inter oolitic pores (inter oolite porosity, are taken into account. The overall porosity is supposed to be connected and decomposed into oolite porosity and matrix porosity. Within the framework of Hashin composite sphere assemblage (CSA models, a two-step homogenization method is developed. At the first homogenization step, pores are assembled into two layers by using self-consistent scheme (SCS. At the second step, the two porous layers constituting the oolites and the matrix are assembled by using generalized self-consistent scheme (GSCS and referred to as three-phase model. Numerical results are presented for data representative of a porous oolitic limestone. It is shown that the influence of porosity on the overall thermal conductivity of such materials may be significant.

  18. Evaluation of steel slag and crushed limestone mixtures as subbase material in flexible pavement

    Directory of Open Access Journals (Sweden)

    Ahmed Ebrahim Abu El-Maaty Behiry

    2013-03-01

    Full Text Available Steel slag is produced as a by-product during the oxidation of steel pellets in an electric arc furnace. This by-product that mainly consists of calcium carbonate is broken down to smaller sizes to be used as aggregates in pavement layers. They are particularly useful in areas where a good-quality aggregate is scarce. This research study was conducted to evaluate the effect of quantity of steel slag on the mechanical properties of blended mixes with crushed limestone aggregates, which used as subbase material in Egypt. Moreover, a theoretical analysis was employed to estimate the resistance for failure factors such as vertical deformations, vertical and radial stresses and vertical strains of subbase under overweight trucks loads. These loads cause severe deterioration to the pavement and thus reduce its life. The results indicated that the mechanical characteristics, and the resistance factors were improved by adding steel slag to the crushed limestone.

  19. Intermediate-scale sodium-concrete reaction tests with basalt and limestone concrete

    International Nuclear Information System (INIS)

    Hassberger, J.A.; Muhlestein, L.D.

    1981-01-01

    Ten tests were performed to investigate the chemical reactions and rate and extent of attack between sodium and basalt and limestone concretes. Test temperatures ranged from 510 to 870 0 C (950 to 1600 0 F) and test times from 2 to 24 hours. Sodium hydroxide was added to some of the tests to assess the impact of a sodium hydroxide-aided reaction on the overall penetration characteristics. Data suggest that the sodium penetration of concrete surfaces is limited. Penetration of basalt concrete in the presence of sodium hydroxide is shown to be less severe than attack by the metallic sodium alone. Presence of sodium hydroxide changes the characteristics of sodium penetration of limestone concrete, but no major differences in bulk penetration were observed as compared to penetration by metallic sodium

  20. Biological effects of long term fine limestone tailings discharge in a fjord ecosystem.

    Science.gov (United States)

    Brooks, Lucy; Melsom, Fredrik; Glette, Tormod

    2015-07-15

    Benthic infaunal data collected from 1993 to 2010 were analysed to examine the effect of long term discharge of fine limestone tailings on macrofaunal species assemblages in a fjord. Relative distance from the outfall and proportion of fine tailings in the sediment were correlated with benthic community structure. Diversity decreased with increasing proportion of fine tailings. Biological Traits Analysis (BTA) was used to explore the temporal and spatial effects of the tailings gradient on macrofaunal functional attributes. BTA revealed that all stations along a pressure gradient of fine limestone tailings were dominated by free-living species. As the proportion of fine tailings in the sediment increased, there was an increase in fauna that were smaller, highly mobile, living on or nearer the surface sediment, with shorter lifespans. There was a decrease in permanent tube dwellers, those fauna with low or no mobility, that live deeper in the sediment and have longer lifespans (>5 yrs). Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Physiological and behavioral response of stonefly nymphs to enhanced limestone treatment of acid mine drainage

    Energy Technology Data Exchange (ETDEWEB)

    Cole, M.B.; Arnold, D.E.; Watten, B.J. [ABR Inc., PO Box 249, OR (USA). Environmental Research and Services

    2001-07-01

    A new acid mine drainage (AMD) treatment system uses pulsed, fluidized beds of limestone, and carbon dioxide pretreatment of influent AMD to enhance limestone neutralization of AMD. Laboratory studies were carried out to evaluate the behavior and physiology of larval stoneflies (Pteronarcys proteus, Plecoptera) exposed to effluents produced by the treatment system. Survival, sodium balance, drift, and feeding responses by P. proteus to treated and untreated AMD were examined. P. proteus nymphs exhibited significant losses of whole body sodium in exposures to untreated AMD. Nymphs exposed to treated effluents experienced no loss of whole-body sodium. No significant differences in feeding or drift behavior occurred between nymphs exposed to treated effluents and those exposed to AMD-free controls. The treatment system, with and without CO{sub 2} pretreatment, provided water that was not toxic to the test animals, and that allowed normal behavioral and physiological function.

  2. Hydrobiogeochemical interactions in 'anoxic' limestone drains for neutralization of acidic mine drainage

    Science.gov (United States)

    Robbins, E.I.; Cravotta, C.A.; Savela, C.E.; Nord, G.L.

    1999-01-01

    Processes affecting neutralization of acidic coal mine drainage were evaluated within 'anoxic' limestone drains (ALDs). Influents had pH???3.5 and dissolved oxygen Al3+ and Fe3+ compounds. Cleavage mounts of calcite and gypsum that were suspended within the ALDs and later examined microscopically showed dissolution features despite coatings by numerous bacteria, biofilms, and Fe-Al-Si precipitates. In the drain exhibiting the greatest flow reduction, Al-hydroxysulfates had accumulated on limestone surfaces and calcite etch points, thus causing the decline in transmissivity and dissolution. Therefore, where Al loadings are high and flow rates are low, a pre-treatment step is indicated to promote Al removal before diverting acidic mine water into alkalinity-producing materials. ?? 1998 Elsevier Science Ltd.

  3. Evaluation of modeling approaches to simulate contaminant transport in a fractured limestone aquifer

    DEFF Research Database (Denmark)

    Mosthaf, Klaus; Fjordbøge, Annika Sidelmann; Broholm, Mette Martina

    in fractured limestone aquifers. The model comparison is conducted for a contaminated site in Denmark, where a plume of dissolved PCE has migrated through a fractured limestone aquifer. Field data includes information on spill history, distribution of the contaminant (multilevel sampling), geology...... and hydrogeology. To describe the geology and fracture system, data from borehole logs and cores was combined with an analysis of heterogeneities and fractures from a nearby excavation and pump test data. We present how field data is integrated into the different model concepts. A challenge in the use of field...... and remediation strategies. Each model is compared with field data, considering both model fit and model suitability. Results show a considerable difference between the approaches, and that it is important to select the right one for the actual modeling purpose. The comparison with data showed how much...

  4. Comparison of different modeling approaches to simulate contaminant transport in a fractured limestone aquifer

    DEFF Research Database (Denmark)

    Mosthaf, Klaus; Rosenberg, L.; Balbarini, Nicola

    . Given available field data and model purpose, this paper therefore aims to develop, examine and compare modeling approaches for transport of contaminants in fractured limestone aquifers. The model comparison was conducted for a contaminated site in Denmark, where a plume of a dissolved contaminant (PCE...... was combined with an analysis of heterogeneities and fractures from a nearby excavation (analog site). Methods for translating the geological information and fracture mapping into each of the model concepts were examined. Each model was compared with available field data, considering both model fit...... of field data is the determination of relevant hydraulic properties and interpretation of aqueous and solid phase contaminant concentration sampling data. Traditional water sampling has a bias towards fracture sampling, however concentrations in the limestone matrix are needed for assessing contaminant...

  5. Mechanical and chemical compaction in fine-grained shallow-water limestones.

    Science.gov (United States)

    Shinn, E.A.; Robbin, D.M.

    1983-01-01

    Significant mechanical compaction resulted from pressures simulating less than 305 m of burial. Increasing loads to an equivalent of more than 3400 m did not significantly increase compaction or reduce sediment core length. Chemical compaction (pressure dissolution) was detected only in sediment cores compacted to pressures greater than 3400 m of burial. These short-term experiments suggest that chemical compaction would begin at much shallower depths given geologic time. Compaction experiments that caused chemical compaction lend support to the well-established hypothesis; that cement required to produce a low-porosity/low-permeability fine-grained limestone is derived internally. Dissolution, ion diffusion, and reprecipitation are considered the most likely processes for creating significant thicknesses of dense limestone in the geologic record. Continuation of chemical compaction after significant porosity reduction necessitates expulsion of connate fluids, possibly including hydrocarbons. -from Authors

  6. Soil-gas diffusivity fingerprints of the dual porosity system in fractured limestone

    DEFF Research Database (Denmark)

    Claes, Niels; Chamindu, D.T.K.K.; Jensen, Jacob Birk

    2010-01-01

    processes are mostly limited to hydrogeological (water and solute) transport studies with very poor attention to the gaseous phase transport studies (Kristensen et al. 2010). This study characterizes fractured limestone soils for gas diffusion based on three different gas diffusivity fingerprints. The first...... fingerprint is a two-parameter exponential model, which mainly describes the gas diffusivity in the limestone matrix while taking both fracture connectivity and matrix pore connectivity into account. With the second fingerprint, we make a close observation of the tortuous matrix pore network by means...... of a modified Buckingham (1904) pore connectivity factor (X*). The third fingerprint of the fracture network involves the average angle of diffusion α (Moldrup et al. 2010), a parameter which characterizes the average angle at which the fractures are penetrating the sample....

  7. Arbuscular mycorrhizal fungi in a semi-arid, limestone mining-impacted area of Brazil

    Directory of Open Access Journals (Sweden)

    Thaís Teixeira-Rios

    2013-12-01

    Full Text Available The main goal of this study was to determine the diversity and activity of arbuscular mycorrhizal fungi (AMF in an area degraded by limestone mining within the semi-arid region of Brazil known as the caatinga (shrublands. Near a limestone quarry, we selected two areas of caatinga (preserved and degraded for study. The number of glomerospores did not differ significantly between the two areas. There was a trend toward the most probable number of infective propagules being higher in the degraded area. Twenty AMF taxa were identified in the two sampled areas, species richness, diversity and evenness being higher in the preserved area. Two species of Racocetra represent new records for the semi-arid region of Brazil. Glomerospore production and AMF species richness were unaffected by mining activity in the study area.

  8. Investigations of a Cretaceous limestone with spectral induced polarization and scanning electron microscopy

    DEFF Research Database (Denmark)

    Johansson, Sara; Sparrembom, Charlotte; Fiandaca, Gianluca

    2017-01-01

    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...... in early time ranges for bedrock characterization. The inverted sections showed variations within the limestone that could be 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......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...

  9. Physico-chemical investigations of limestones from different localities in the Republic of Macedonia

    International Nuclear Information System (INIS)

    Arabadzhiev, Dimitrios M.; Stefov, Viktor; Boev, Blazho

    2001-01-01

    Physico-chemical investigations were carried out for limestone samples at different localities in the Republic of Macedonia: mine for nonmetals O graiden , Strumica (sample-granulation below: 4, 10, 20, 32, 40, 63 and 90 gm), A.D. M ikrogranulat , Gostivar, mine 'Banjani' - Skopje, mine 'Toplica' near Demir Hisar and from the separation of GP Mavrovo, Skopje, located near Pletvar. Investigation of samples from the previously mentioned localities were carried out using different methods: volumetry, gravimetry, UV-VIS and infrared spectroscopy, as well as atomic absorption and X-ray fluorescence spectrometry, X-ray diffraction and flame photometry. The obtained results lead to the conclusion that all granulometric classes of the limestone samples from 'Ograzhden', Strumica, are of the best quality. (Original)

  10. Paleokarst processes in the Eocene limestones of the Pyramids Plateau, Giza, Egypt

    Science.gov (United States)

    El Aref, M. M.; Refai, E.

    The Eocene limestones of the Pyramids plateau are characterized by landforms of stepped terraced escarpment and karst ridges with isolated hills. The carbonate country rocks are also dominated by minor surface, surface to subsurface and subsurface solution features associated with karst products. The systematic field observations eludicate the denudation trend of the minor solution features and suggest the origin of the regional landscapes. The lithologic and structural characters of the limestone country rocks comprise the main factors controlling the surface and subsurface karst evolution. The development of the karst features and the associated sediments in the study area provides information on the paleohydrolic, chemical and climatic environments involved in the origin of the karstification.

  11. Limestone: some observations on luminescence in the region of 360 nm

    International Nuclear Information System (INIS)

    Galloway, R.B.

    2003-01-01

    An empirical study of luminescence around 360 nm from limestone is presented. Thermoluminescence glow curves from natural limestone show broad peaks at 440 deg. C, 350 deg. C, 530 deg. C and 286 deg. C in order of decreasing amplitude in contrast to the usual observation, for luminescence around 535 nm, of a sharp peak at 286 deg. C with a broader less intense peak at 350 deg. C. Recuperation occurs around 350 deg. C and 525 deg. C, which has a time dependence consistent with quantum tunnelling. Dependent on the history of heating and light exposure of the sample, sharp peaks at about 325 deg. C and 425 deg. C can be observed. Laboratory irradiated limestone shows a peak at 140 deg. C. The stimulation of luminescence by light of 470 nm with preheating at 145 deg. C for 300 s, shows an increasing signal for successive cycles of measurement associated with the heating, light exposure having little influence. Beta irradiation of a sample, with the same measurement conditions, gives a signal which increases in proportion to radiation dose but which does not survive storage for 17 h. Time resolved luminescence spectra, with no preheating, show a luminescence lifetime between stimulation and emission of less than a few μs for natural limestone, and an exponential increase in signal with increase in temperature (over the rang 20-167 deg. C) during stimulation. A signal proportional to laboratory applied beta dose is measurable at room temperature, with lifetime between stimulation and emission of this signal of 35 μs, but it does not survive heating to 100 deg. C

  12. [Effects of variable temperature on organic carbon mineralization in typical limestone soils].

    Science.gov (United States)

    Wang, Lian-Ge; Gao, Yan-Hong; Ding, Chang-Huan; Ci, En; Xie, De-Ti

    2014-11-01

    Soil sampling in the field and incubation experiment in the laboratory were conducted to investigate the responses of soil organic carbon (SOC) mineralization to variable temperature regimes in the topsoil of limestone soils from forest land and dry land. Two incubated limestone soils were sampled from the 0-10 cm layers of typical forest land and dry land respectively, which were distributed in Tianlong Mountain area of Puding county, Guizhou province. The soils were incubated for 56 d under two different temperature regimes including variable temperature (range: 15-25 degrees C, interval: 12 h) and constant temperature (20 degrees C), and the cumulative temperature was the same in the two temperature treatments. In the entire incubation period (56 d), the SOC cumulative mineralization (63.32 mg x kg(-1)) in the limestone soil from dry land (SH) under the variable temperature was lower than that (63.96 mg x kg(-1)) at constant 20 degrees C, and there was no significant difference in the SOC cumulative mineralization between the variable and constant temperature treatments (P variable temperature was significantly lower than that (209.52 mg x kg(-1)) at constant 20 degrees C. The results indicated that the responses of SOC mineralization to the variable temperature were obviously different between SL and SH soils. The SOC content and composition were significantly different between SL and SH soils affected by vegetation and land use type, which suggested that SOC content and composition were important factors causing the different responses of SOC mineralization to variable temperature between SL and SH soils. In addition, the dissolved organic carbon (DOC) content of two limestone soils were highly (P variable temperature mainly influenced SOC mineralization by changing microbial community activity rather than by changing microbial quantity.

  13. Towards Early Age Characterisation of Eco-Concrete Containing Blast-Furnace Slag and Limestone Filler

    OpenAIRE

    Carette, Jerome

    2015-01-01

    It is estimated that concrete represents 5% of the anthropogenic CO2 emissions, mainly originating from the production of cement, the most essential component of concrete. The recent awareness to the environmental challenges facing our civilization has led the cement industry to consider substituting cement by mineral additions, by-products of existing industries. In this work, a combination of limestone filler and blast furnace slag is used to design an “eco-concrete”, defined as a concrete ...

  14. Estimation of deep infiltration in unsaturated limestone environments using cave lidar and drip count data

    OpenAIRE

    Mahmud, K.; Mariethoz, G.; Baker, A.; Treble, P. C.; Markowska, M.; McGuire, E.

    2016-01-01

    Limestone aeolianites constitute karstic aquifers covering much of the western and southern Australian coastal fringe. They are a key groundwater resource for a range of industries such as winery and tourism, and provide important ecosystem services such as habitat for stygofauna. Moreover, recharge estimation is important for understanding the water cycle, for contaminant transport, for water management, and for stalagmite-based paleoclimate reconstructions. Caves offer a n...

  15. Block Volume Estimation from the Discontinuity Spacing Measurements of Mesozoic Limestone Quarries, Karaburun Peninsula, Turkey

    OpenAIRE

    Elci, Hakan; Turk, Necdet

    2014-01-01

    Block volumes are generally estimated by analyzing the discontinuity spacing measurements obtained either from the scan lines placed over the rock exposures or the borehole cores. Discontinuity spacing measurements made at the Mesozoic limestone quarries in Karaburun Peninsula were used to estimate the average block volumes that could be produced from them using the suggested methods in the literature. The Block Quality Designation (BQD) ratio method proposed by the authors has been found to ...

  16. Mississippian reef development in the Cracoe Limestone Formation of the southern Askrigg Block, North Yorkshire, UK

    OpenAIRE

    Waters, C.N.; Haslam, R.B.; Cózar, P.; Somerville, I.D.; Millward, D.; Woods, M.

    2017-01-01

    The southern margin of the Askrigg Block around Cracoe, North Yorkshire, shows a transition from carbonate ramp to reef-rimmed shelf margin, which, based on new foraminiferal/algal data, is now constrained to have initiated during the late Asbian. A late Holkerian to early Asbian ramp facies that included small mudmounds developed in comparatively deeper waters, in a transition zone between the proximal ramp, mudmound-free carbonates of the Scaleber Quarry Limestone Member (Kilnsey Formation)...

  17. Limestone and oyster shell for brown layers in their second egg production cycle

    Directory of Open Access Journals (Sweden)

    CC Pizzolante

    2011-06-01

    Full Text Available This study aimed at evaluating the effect of dietary calcium levels and the replacement of calcium sources with different particle size compositions on the performance and egg quality of brown layers in their second egg production cycle. A randomized block experimental design was applied with 12 treatments in a 3x4 factorial arrangement: three calcium levels (2.6, 3.2, 3.8 % and four combinations of calcium sources (1- 100% fine limestone (FL, 2- 50% FL + 50% coarse limestone (CL, 3- 50% FL and 50% oyster shell (OS, 4- 50% FL and 25% CL+ 25 %OS, with six replicates of eight birds each. Calcium sources were analyzed for geometric mean diameter (GMD and in-vitro solubility. The following performance and egg quality parameters were evaluated: egg weight (EW, g, egg production (% Eggs, egg mass (EM %, feed intake (FI g, feed conversion ratio (FCR kg/dz and FCR kg/kg, mortality (% Mort., specific egg gravity (SG, percentages of yolk (Y%, albumen (Alb% and eggshell (ES%, eggshell thickness (EST, eggshell breaking strength (BS, eggshell weight per surface area (EWSA, Haugh unit (HU, yolk index (YI and yolk color. Performance and internal egg quality were not affected by the treatments (p>0.05. Blocks had a significant effect on (p<0.05 FI and FCR (kg/dz and kg/kg. Treatments significantly influenced external egg quality, which improved as dietary calcium levels increases and when up to 50% fine limestone was replaced by combinations of coarse limestone with oyster shell.

  18. Stability of an anaerobic single reactor filled with dolomitic limestone with increased organic load of sugarcane

    Directory of Open Access Journals (Sweden)

    Maria Magdalena Ribas Döll

    2017-12-01

    Full Text Available The anaerobic single-stage reactor was evaluated to treat vinasse and to evaluate its stability. This bench reactor was filled with dolomitic limestone with a horizontal plug flow to simulate a drainage channel. The experiment lasted 129 days while the reactor was submitted to different applied organic concentrations (chronologically applied: 3.0; 5.0; 12.0; 9.0 and 7.5 g L-1 as COD, chemical oxygen demand. COD removals were 50% and 9% with 3.0 and 7.5 g L-1, respectively. With 12.0 g L-1, reactor efficiency increased to 33%, with an abrupt drop to 3% on the 84th day. Therefore, in order to avoid reactor collapse, a remedial measure was necessary. The system remained in batch without feeding for 19 days (from the 85th to the 104th day with 9.0 g L-1. Afterwards, it was observed that the performance of the system tended to stabilize, reaching 47% with 7.5 g L-1 in the 118th day. At the end of the experiment, the potassium content of the wastewater decreased from 800 mg L-1 to 594 mg L-1 (on an average 25% and calcium and magnesium increased within the reactor liquor. The dissolution of the limestone inside the liquor reactor probably caused this result. After the treatment with limestone, the average pH value of the effluent increased from 4.9 to over 6.0 in all organic concentrations. It could be concluded that the reactor filled with dolomitic limestone in these operational conditions assured a low efficiency in COD removal, potassium reduction, increasing values of pH, alkalinity, calcium and magnesium. The instability was observed when there was increase in organic load to 12 g L-1 with subsequent recovery.

  19. Properties, sustainability and elevated temperature behavior of concrete containing Portland limestone cement

    Science.gov (United States)

    El-Hawary, Moetaz; Ahmed, Mahmoud

    2017-09-01

    The utilization of some type of cheap filler as partial cement replacement is an effective way of improving concrete sustainability. With the recent trends to reduce water to cement ratio and improve compaction, there is no enough space or water for complete hydration of cement. This means that actually, a portion of mixed cement acts as expensive filler. Replacing this portion with cheaper filler that requires less energy to produce is, therefore, beneficial. Crushed limestone is the most promising filler. This work is to investigate the effect of the amount of limestone fillers on the sustainability and the fresh and mechanical properties of the resulting concrete. A rich mix is designed with a low water/cement ratio of 0.4. Lime is introduced as a replacement percentage of cement. Ratios of 0, 10, 20 and 30% were used. Slump, compressive strength, specific gravity and water absorption are evaluated for every mix. In addition, the effect of the amount of lime on the residual strength of concrete subjected to elevated temperatures is also investigated. Samples are subjected to six different temperature stations of 20, 100, 200, 300, 500 and 700°C for six hours before being cooled and subsequently tested for compressive strength and specific gravity. Sustainability of the tested mixes is evaluated through reductions in the emitted carbon dioxide, energy and reduction in cost. Based on the annual use of concrete in Kuwait, the sustainability benefits resulting from the use of limestone filler in Kuwait are evaluated and assessed. The paper is concluded with the recommendation of the use of 15% limestone filler as partial cement replacement where the properties and the behavior under high temperature of the resulting concrete are almost the same as those of conventional concrete with considerable cost and sustainability benefits.

  20. Determination of calcium and iron in limestone by X-ray fluorescence method

    International Nuclear Information System (INIS)

    Sovtsova, M.K.

    1977-01-01

    The results of determining calcium and iron content in limestone by X-ray fluorescence method are described. The 109 Cd isotape was chosen as a source for excitation, as it permited to reduce the concentration degeneration in the range of large Ca contents due to the larger energy of the primary radiation. The root-mean-square deviation from the data of chemical analysis was +-0.02%FeO and +-0.22%CaO

  1. Dinosaur footprints in the Upper Turonian-Coniacian limestone in the Krnica Bay (NE Istria, Croatia

    Directory of Open Access Journals (Sweden)

    Alenka Mauko

    2003-06-01

    Full Text Available Three isolated footprints and one trackway that can be attributed to bipedal dinosaur, from a limestone bed in vicinity of Požara promontory, Krnica Bay, are described. According to the stratigraphic position the footprints are late Turonian to Coniacian in age.This is the first record of dinosaur remains in the Turonian-Coniacian and the youngest footprint site on the Adriatic-Dinaric Carbonate Platform described thus far.

  2. French electric power balance sheet 2009

    International Nuclear Information System (INIS)

    Lartigau, Thierry; Riere, Alexia

    2010-01-01

    The mission of RTE, the French electricity Transportation grid, a public service assignment, is to balance the electricity supply and demand in real time. This report presents RTE's technical results for the year 2009: key figures of the French electricity consumption, lowering of the French power generation, decrease of trade balance at borders but still positive, continuation of RTE's investments for the improvement of the grid performance. New RTE's infrastructures, electricity quality data, and the evolution of market mechanisms are presented in appendixes

  3. Foreign direct investments into French real estate

    OpenAIRE

    BRIZARD, Arthur

    2013-01-01

    The purpose of this thesis is to draw the global trend of Foreign Direct Investments (FDI) in the French real estate market since 2008 and to understand foreign investors’ behavior and the incentives which urge them to invest in French property market. This study relies on the numerous yearly reports released by consulting and real estate companies and gives an overview of FDI since 2008. From a legal point of view, the French property market is extremely organized. Acquiring, holding and sel...

  4. Decomposition and reduction of N2O over Limestone under FBC Conditions

    DEFF Research Database (Denmark)

    Johnsson, Jan Erik; Jensen, Anker; Vaaben, Rikke

    1997-01-01

    The addition of limestone for sulfur retention in FBC has in many cases been observed to influence the emission of N2O. The catalytic activity of N2O over calcined Stevns Chalk for decomposition of N2O in a laboratory fixed bed quartz reactor was measured. It was found that calcined Stevns Chalk...... is a very active catalyst for N2O decomposition in an inert atmosphere, and the presence of 3 vol% CO increased the rate of N2O destruction by a factor of 5 due to the catalytic reduction of N2O by CO. The activity decreased with increasing CO2 concentration, and uncalcined or recarbonated limestone had...... negligible activity. Sulfation of the calcined limestone under oxidizing conditions lowered the activity, however sulfidation under reducing conditions showed that CaS is an active catalyst for the reduction of N2O by CO. Without CO present a gas solid reaction between N2O and CaS takes place and SO2...

  5. Experimental study of the effect of limestone grading on some mechanical properties of concrete

    Directory of Open Access Journals (Sweden)

    Ammari Madiha Z. J.

    2017-01-01

    Full Text Available This study reports the experimental work undertaken to investigate the optimum grading of limestone to be used in concrete mixes. 36 concrete cubes were prepared for testing. Four different Fineness Moduli and grading were tested 2.4, 2.6, 2.92 and 3. For all tests, the cubes were left in curing until testing at the age of 3, 7 and 28 days respectively. Samples were loaded to failure and the average compressive strength was used for comparison purposes. Flow table test has been performed on the fresh concrete directly after mixing to measure workability and the average of the maximum concrete spread parallel to the two edges of the table was recorded. Results revealed that the optimum Fineness Modulus for the limestone to be used as fine aggregate in the concrete mix to get maximum compressive strength is 2.78. The flow table tests revealed an increment in the workability of fresh concrete with higher Fineness Modulus of limestone used in the concrete mix as fine aggregate. The workability of the optimum Fineness Modulus, 2.78, was found to be 412 mm which is a mix with considerable workability. An ideal grading has been recommended in this research study and checked to match the ASTM grading requirements for fine aggregate.

  6. TL glow curve analysis of UV, beta and gamma induced limestone collected from Amarnath holy cave

    Directory of Open Access Journals (Sweden)

    Vikas Dubey

    2015-01-01

    Full Text Available The paper reports themoluminescence glow curve analysis of UV (ultraviolet, β (beta and γ (gamma induced limestone collected from Amarnath holy cave. The collected natural sample was characterized by X-ray diffraction (XRD technique and crystallite size calculated by Scherer's formula. Surface morphology and particle size was calculated by transmission electron microscopy (TEM study. Effect of annealing temperature on collected lime stone examined by TL glow curve study. The limestone was irradiated by UV radiation (254 nm source and the TL glow curve recorded for different UV exposure time. For beta irradiation Sr90 source was used and is shows intense peak at 256 °C with a shoulder peak at higher temperature range. For gamma radiation Co60 source and TL glow curve recorded for different doses of gamma. The kinetic parameters calculation was performed for different glow curve by computerized glow curve deconvolution (CGCD technique. The chemical composition of natural limestone was analyzed by energy dispersive X-ray spectroscopy (EDXS.

  7. The influence of temperature on limestone sulfation and attrition under fluidized bed combustion conditions

    Energy Technology Data Exchange (ETDEWEB)

    Montagnaro, Fabio [Dipartimento di Chimica - Universita degli Studi di Napoli Federico II, Complesso Universitario del Monte di Sant' Angelo, 80126 Napoli (Italy); Salatino, Piero [Istituto di Ricerche sulla Combustione - CNR, Piazzale Vincenzo Tecchio 80, 80125 Napoli (Italy); Dipartimento di Ingegneria Chimica - Universita degli Studi di Napoli Federico II, Piazzale Vincenzo Tecchio 80, 80125 Napoli (Italy); Scala, Fabrizio [Istituto di Ricerche sulla Combustione - CNR, Piazzale Vincenzo Tecchio 80, 80125 Napoli (Italy)

    2010-04-15

    The influence of temperature on attrition of two limestones during desulfurization in a fluidized bed reactor was investigated. Differences in the microstructure of the two limestones were reflected by a different thickness of the sulfate shell formed upon sulfation and by a different value of the ultimate calcium conversion degree. Particle attrition and fragmentation were fairly small under moderately bubbling fluidization conditions for both limestones. An increase of temperature from 850 C to 900 C led to an increase of the attrition rate, most likely because of a particle weakening effect caused by a faster CO{sub 2} evolution during calcination. This weakening effect, however, was not sufficiently strong to enhance particle fragmentation in the bed. The progress of sulfation, associated to the build-up of a hard sulfate shell around the particles, led in any case to a decrease of the extent of attrition. Sulfation at 900 C was less effective than at 850 C, and this was shown to be related to the porosimetric features of the different samples. (author)

  8. Treatment of iron(II)-rich acid mine water with limestone and oxygen.

    Science.gov (United States)

    Mohajane, G B; Maree, J P; Panichev, N

    2014-01-01

    The main components of acid mine water are free acid, sulphate, and Fe²⁺. Limestone is the most cost-effective alkali that can be used for neutralization. The purpose of this investigation was to identify conditions where Fe²⁺ is removed with limestone and simultaneously oxidized with oxygen to Fe³⁺, in a polyvinyl chloride pipe under pressure. Gypsum scaling is prevented by passing rubber balls through the pipe of the so-called Oxygen-Pipe-Neutralization (OPeN) process pilot plant. Two synthetic waters were treated: (A) acid mine water containing 123 mg L⁻¹ Fe²⁺ representing gold mine water, and (B) acid mine water containing 6,032 mg L⁻¹ Fe²⁺ representing coal mine water. Batch studies were carried out in a pipe reactor and showed that the rate of Fe²⁺ oxidation depended on the Fe²⁺ concentration, oxygen pressure, amount of recycled sludge, limestone dosage and the mixing rate. Continuous studies in an OPeN process pilot plant resulted in 100% removal of total acidity from synthetic coal mine water and a 98% removal from synthetic gold mine water. Fe²⁺ was removed completely as precipitated Fe(OH)₃ from both synthetic coal and gold mine water at around pH 7 at 200 and 100 kPa oxygen pressure, respectively.

  9. Report of investigation on underground limestone mines in the Ohio region

    International Nuclear Information System (INIS)

    Byerly, D.W.

    1976-06-01

    The following is a report of investigation on the geologic setting of several underground limestone mines in Ohio other than the PPG mine at Barberton, Ohio. Due to the element of available time, the writer is only able to deliver a brief synopsis of the geology of three sites visited. These three sites and the Barberton, Ohio site are the only underground limestone mines in Ohio to the best of the writer's knowledge. The sites visited include: (1) the Jonathan Mine located near Zanesville, Ohio, and currently operated by the Columbia Cement Corporation; (2) the abandoned Alpha Portland Cement Mine located near Ironton, Ohio; and (3) the Lewisburg Mine located at Lewisburg, Ohio, and currently being utilized as an underground storage facility. Other remaining possibilities where limestone is being mined underground are located in middle Ordovician strata near Carntown and Maysville, Kentucky. These are drift mines into a thick sequence of carbonates. The writer predicts, however, that these mines would have some problems with water due to the preponderance of carbonate rocks and the proximity of the mines to the Ohio River. None of the sites visited nor the sites in Kentucky have conditions comparable to the deep mine at Barberton, Ohio

  10. Hydraulic retention time on vinasse stabilisation with limestone in the acidogenic phase of anaerobic digestion

    Directory of Open Access Journals (Sweden)

    Ismael Plácido Tomielis

    Full Text Available ABSTRACT: The main problem in anaerobic digestion of low-protein residues is the instability caused acidity. The use of limestone at the same time as a neutralizing agent and support material is innovative because stones wear allows the slow release of the calcium carbonate thereby eliminating dispersers. Free calcium content in the system was measured in two plug flow reactors filled with vinasse at initial pH of 4.50. The proportion of 1.8 tonnes of limestone per m³ of vinasse was evaluated at the Hydraulic Retention Times (HRT of 24, 48, 72, 96 and 120 hours, allowing stabilisation at 96 hours. The ratio of Volatile Acids/Total Alkalinity (VA/TA ranged from 0.2 to 0.4 and the pH reached 7.0, at the HRT of 120 hours. Increasing the HRT also increased the volatile total solids (VTS and fixed total solids (TFS in a similar profile to the measured free calcium content, but calcium remained at the appropriate level of 100 to 250mg l-1. The proportion of limestone/vinasse was adequate to ensure stabilisation, but it is not recommended to reduce the HRT below 96 hours due to the risk of compromising the stability of the anaerobic system.

  11. Economical assessment of competitive enhanced limestones for CO2 capture cycles in power plants

    International Nuclear Information System (INIS)

    Romeo, Luis M.; Lara, Yolanda; Lisbona, Pilar; Martinez, Ana

    2009-01-01

    CO 2 capture systems based on the carbonation/calcination loop have gained rapid interest due to promising carbonator CO 2 capture efficiency, low sorbent cost and no flue gases treatment is required before entering the system. These features together result in a competitively low cost CO 2 capture system. Among the key variables that influence the performance of these systems and their integration with power plants, the carbonation conversion of the sorbent and the heat requirement at calciner are the most relevant. Both variables are mainly influenced by CaO/CO 2 ratio and make-up flow of solids. New sorbents are under development to reduce the decay of their carbonation conversion with cycles. The aim of this study is to assess the competitiveness of new limestones with enhanced sorption behaviour applied to carbonation/calcination cycle integrated with a power plant, compared to raw limestone. The existence of an upper limit for the maximum average capture capacity of CaO has been considered. Above this limit, improving sorbent capture capacity does not lead to the corresponding increase in capture efficiency and, thus, reduction of CO 2 avoided cost is not observed. Simulations calculate the maximum price for enhanced sorbents to achieve a reduction in CO 2 removal cost under different process conditions (solid circulation and make-up flow). The present study may be used as an assessment tool of new sorbents to understand what prices would be competitive compare with raw limestone in the CO 2 looping capture systems. (author)

  12. Stable isotope stratigraphy and larger benthic foraminiferal extinctions in the Melinau Limestone, Sarawak

    Science.gov (United States)

    Cotton, Laura J.; Pearson, Paul N.; Renema, Willem

    2014-01-01

    Important long-ranging groups of larger benthic foraminifera (LBF) are known to have become extinct during a period of global cooling and climate disruption at the Eocene-Oligocene transition (EOT) but the precise timing and mechanisms are uncertain. Recent study showed unexpectedly that the LBF extinction in Tanzania occurs very close to the Eocene/Oligocene boundary, as recognised by the extinction of the planktonic foraminiferal Family Hantkeninidae, rather than at the later period of maximum global ice growth and sea-level fall, as previously thought. Here we investigate the same phase of extinction in the Melinau Limestone of Sarawak, on the island of Borneo, Malaysia one of the most complete carbonate successions spanning the Eocene to Lower Miocene. Assemblages of LBF from the Melinau Limestone were studied extensively by Geoffrey Adams during the 1960s-80s, confirming a major extinction during the EOT, but the section lacked independent means of correlation. By analysing rock samples originally studied by Adams and now in the Natural History Museum, London, we provide new bulk stable isotope (δ13C and δ18O) records. This enables us to identify, albeit tentatively, the level of maximum stable isotope excursion and show that the LBF extinction event in the Melinau Limestone occurs below this isotope excursion, supporting the results from Tanzania and indicating that the extinction of LBF close to the Eocene/Oligocene boundary may be a global phenomenon.

  13. A Stranger in the Midst: Searching for Relict Grains from Rare Meteorite Types in Mid-Ordovician Limestone Strata

    Science.gov (United States)

    Martin, E.; Schmitz, B.

    2016-08-01

    A layer of Mid-Ordovician limestone harbors exceptional amounts of L-chondritic chromite grains. The layer also contains grains from potentially rarer types of meteorites, following the discovery of the fossil meteorite Österplana 065.

  14. Reduction of SO sub 2 emission from a fluidized-bed under staged combustion by coarse limestone

    International Nuclear Information System (INIS)

    Khan, W.Z.; Gibbbs, B.M.

    1998-01-01

    A study was performed to investigate the effect of course limestone on the reduction of SO sub 2 emission from a fluidized-bed under staged combustion. The limestone of 1.2-2.5 mm size was premixed with fine coal of 1-3 mm size and fed under bed. The staging levels, bed height, and Ca/S ratio was fixed at 70:30, 30 cm and 3:1, respectively. A maximum of around 50% reduction in SO sub 2 emissions was achieved at both excess air of 20 and 40% and at 830 deg. C. bed temperature. The SO sub 2 emissions were very sensitive to bed temperature. The course limestone was found better in desulfurization efficiency at lower temperature than fine limestone. (author)

  15. Discontinuity surfaces and event stratigraphy of Okha Shell Limestone Member: Implications for Holocene sea level changes, western India

    Science.gov (United States)

    Bhonde, Uday; Desai, Bhawanisingh G.

    2011-08-01

    The Okha Shell Limestone Member of Chaya Formation is the coarse grained, shell rich deposit commonly recognized as the beach rocks. It has been age bracketed between Late Pleistocene and Holocene. Late Quaternary sea level changes have been studied with beach rocks along the Saurashtra coastal region. The present study has been carried out in the Okhamandal area of the Saurashtra peninsula especially on the Okha Shell Limestone Member as exposed at various locations along the coast from north to south. Temporal and spatial correlations of the observations have revealed three events in the Okha Shell Limestone Member of Chaya Formation that are correlated laterally. The events show depositional breaks represented by discontinuity surfaces, the taphofacies varieties and ichnological variations. The present study in the context of available geochrnological data of the region suggests a prominent depositional break representing low sea level stand (regression) during an Early Holocene during the deposition of Okha Shell Limestone Member.

  16. Radio cobalt in French rivers

    International Nuclear Information System (INIS)

    Lambrechts, A.; Baudin-Jaulent, Y.

    1996-01-01

    The isotopes 58 and 60 of cobalt present in liquid wastes from nuclear plants or from fuel reprocessing plant of Marcoule are fixed in the different compartments of French rivers. The activity levels of radio-cobalt vary according to the sampled compartments nature (bryophyta > immersed plants > sediment > fish). Elsewhere, laboratory experimentations show that the contamination of fish occurs essentially from the water way rather than from food. Cobalt is mainly fixed by kidneys; muscles is no more than 30 % of the total fish activity. (author)

  17. French programme for HTR fuel

    International Nuclear Information System (INIS)

    Gillet, R.M.

    1991-01-01

    It is reported that in the frameworks of the French HTR research program, stopped in 1979 the HTR coated particle fuel, fuel rod and prismatic fuel element design have been successfully developed and irradiation tested in France and specific examination methods for irradiated fuel particles, rods and graphite blocks have been developed. Currently CEA is involved in fission product transport experiments sponsored by the US Department of Energy and performed in the COMEDIE loop. Finally the CEA follows progress and developments in HTR fuel research and development throughout the world. 1 tab

  18. Future perspectives of French dissuasion

    International Nuclear Information System (INIS)

    Duval M.

    1996-01-01

    If the French deterrence must disappear in aid of an European deterrence, it will be necessary to take in account the development of nuclear weapon in Asia and then our deterrence system should maintain its credibility by getting the appropriate length. If policy problems are as important for civil nuclear than for military nuclear, it will be necessary to show concern about them because the Asian economy is in full development and Asia is not so frightened by nuclear power than Europe. (N.C.)

  19. French regulations and waste management

    International Nuclear Information System (INIS)

    Sousselier, Y.

    1985-01-01

    The authors describe the organization and the role of safety authorities in France in matter of waste management. They precise the French policy in waste storage and treatment: basic objectives, optimization of waste management. The safety requirements are based upon the barrier principle. Safety requirements about waste conditioning and waste disposal are mentioned. In addition to the safety analysis and studies described above, the Protection and Nuclear Safety Institute assists the ministerial authorities in the drafting of ''basic safety rules (RFS)'', laying down safety objectives. Appendix 1 and Appendix 2 deal with safety aspects in spent fuel storage and in transportation of radioactive materials [fr

  20. French uranium mining sites remediation

    International Nuclear Information System (INIS)

    Roche, M.

    2002-01-01

    Following a presentation of the COGEMA's general policy for the remediation of uranium mining sites and the regulatory requirements, the current phases of site remediation operations are described. Specific operations for underground mines, open pits, milling facilities and confining the milled residues to meet long term public health concerns are detailed and discussed in relation to the communication strategies to show and explain the actions of COGEMA. A brief review of the current remediation situation at the various French facilities is finally presented. (author)

  1. Porous (Swiss-Cheese Graphite

    Directory of Open Access Journals (Sweden)

    Joseph P. Abrahamson

    2018-05-01

    Full Text Available Porous graphite was prepared without the use of template by rapidly heating the carbonization products from mixtures of anthracene, fluorene, and pyrene with a CO2 laser. Rapid CO2 laser heating at a rate of 1.8 × 106 °C/s vaporizes out the fluorene-pyrene derived pitch while annealing the anthracene coke. The resulting structure is that of graphite with 100 nm spherical pores. The graphitizablity of the porous material is the same as pure anthracene coke. Transmission electron microscopy revealed that the interfaces between graphitic layers and the pore walls are unimpeded. Traditional furnace annealing does not result in the porous structure as the heating rates are too slow to vaporize out the pitch, thereby illustrating the advantage of fast thermal processing. The resultant porous graphite was prelithiated and used as an anode in lithium ion capacitors. The porous graphite when lithiated had a specific capacity of 200 mAh/g at 100 mA/g. The assembled lithium ion capacitor demonstrated an energy density as high as 75 Wh/kg when cycled between 2.2 V and 4.2 V.

  2. The Hidden Lincoln in French Opinion

    Directory of Open Access Journals (Sweden)

    Jacques Portes

    2016-05-01

    Full Text Available Abraham Lincoln has never served as a model for French politicians. He was indeed compared to Carnot, the organizer of the French Revolutionary wars. But when Clemenceau led France in WWI, when De Gaulle stood for France’s independence in WWII, nobody thought of comparing them to Lincoln. This essay analyzes French public opinion during the American Civil War with a focus on Lincoln, based on a study of the few French books published between 1860 and 1865 on the US, diaries, a sample of conservative and republican daily papers, weekly reviews and illustrated newspapers.

  3. Colloquial French the complete course for beginners

    CERN Document Server

    Demouy, Valérie

    2015-01-01

    Colloquial French: The Complete Course for Beginners has been carefully developed by an experienced teacher to provide a step-by-step course to French as it is written and spoken today. Combining a clear, practical and accessible style with a methodical and thorough treatment of the language, it equips learners with the essential skills needed to communicate confidently and effectively in French in a broad range of situations. No prior knowledge of the language is required. Colloquial French is exceptional; each unit presents a wealth of grammatical points that are reinforced with a wide range

  4. Crisis in the French nuclear industry

    International Nuclear Information System (INIS)

    Nectoux, F.

    1991-02-01

    This report discusses the economics of the French nuclear power industry. It considers the dominant position of nuclear power in the French energy system, stresses the scale and causes of the current (1990) economic crisis and dispels the popular misconceptions on the cost efficiency of the French programme. The evidence is based on widely available French documents and articles. The report begins by looking at the background of nuclear power in France then discusses the problem of overcapacity, the technical problems and fall in load factors, generating costs and electricity prices and finally, strategic issues are considered. (UK)

  5. Nitrogen utilization and digestibility of amino acids by lambs fed a high-concentrate diet with limestone or magnesium oxide.

    Science.gov (United States)

    Christiansen, M L; Webb, K E

    1990-07-01

    Effects were evaluated of high dietary levels of magnesium oxide (MgO) or limestone on DM, OM and CP digestibility, N balance and intestinal absorption of amino acids by lambs fed a high concentrate diet. Twelve wether lambs equipped with abomasal and ileal cannulas were blocked by weight and breeding and allotted to treatments in a randomized block design in two consecutive trials. Diets were control (800 g), control plus 1.5% MgO (812 g), control plus 1.5% limestone (812 g) and control plus 3.0% limestone (824 g) fed in two equal portions at 12-h intervals. Ruminal fluid pH differences were small. The pH of ileal digesta was greater (P less than .05) with MgO than with limestone (8.23 vs 7.73). Fecal pH was higher (P less than .01) for lambs fed all mineral treatments (avg 8.75) than for lambs fed the control (7.61) and was higher (P less than .01) when MgO (9.53) rather than limestone (8.36) was fed. Ruminal NH3N was lower (P less than .01) when lambs were fed MgO (11.9 mg/dl) compared with limestone (avg 31.2 mg/dl). Preintestinal DM digestibility was greatest (P less than .10) with limestone (avg 49.5%) feeding compared with feeding MgO (31.2%) or the control (35.4%). About 41.5% more essential (P less than .05) and 48% more nonessential (P less than .03) amino acids reached the small intestine when MgO was fed than when limestone was fed. Partial digestibility of amino acids in the small intestine was reduced (P less than .03) an average of 5 percentage units when MgO or limestone was fed. Feeding high levels of MgO or limestone to lambs did not improve the overall digestibility of DM, OM or CP. In fact, feeding high levels of MgO or limestone appeared to be detrimental, reducing intestinal absorption of amino acids.

  6. Geologic framework and hydrogeologic characteristics of the Glen Rose limestone, Camp Stanley Storage Activity, Bexar County, Texas

    Science.gov (United States)

    Clark, Allan K.

    2004-01-01

    The Trinity aquifer is a regional water source in the Hill Country of south-central Texas that supplies water for agriculture, commercial, domestic, and stock purposes. Rocks of the Glen Rose Limestone, which compose the upper zone and upper part of the middle zone of the Trinity aquifer, crop out at the Camp Stanley Storage Activity (CSSA), a U.S. Army weapons and munitions supply, maintenance, and storage facility in northern Bexar County (San Antonio area) (fig. 1). On its northeastern, eastern, and southern boundaries, the CSSA abuts the Camp Bullis Training Site, a U.S. Army field training site for military and Federal government agencies. During 2003, the U.S. Geological Survey (USGS), in cooperation with the U.S. Army, studied the outcropping Glen Rose Limestone at the CSSA and immediately adjacent area (Camp Stanley study area, fig. 1) to identify and map the hydrogeologic subdivisions and faults of the Glen Rose Limestone at the facility. The results of the study are intended to help resource managers improve their understanding of the distribution of porosity and permeability of the outcropping rocks, and thus the conditions for recharge and the potential for contaminants to enter the Glen Rose Limestone. This study followed a similar study done by the USGS at Camp Bullis (Clark, 2003). The purpose of this report is to present the geologic framework and hydrogeologic characteristics of the Glen Rose Limestone in the study area. The hydrogeologic nomenclature follows that introduced by Clark (2003) for the outcropping Glen Rose Limestone at Camp Bullis in which the upper member of the Glen Rose Limestone (hereinafter, upper Glen Rose Limestone), which is coincident with the upper zone of the Trinity aquifer, is divided into five intervals on the basis of observed lithologic and hydrogeologic properties. An outcrop map, two generalized sections, related illustrations, and a table summarize the description of the framework and distribution of characteristics.

  7. Appropriating Written French: Literacy Practices in a Parisian Elementary Classroom

    Science.gov (United States)

    Rockwell, Elsie

    2012-01-01

    In this article, I examine French language instruction in an elementary classroom serving primarily children of Afro-French immigrants in Paris. I show that a prevalent French language ideology privileges written over oral expression and associates full mastery of written French with rational thought and full inclusion in the French polity. This…

  8. Liquid carbon dioxide/pulverized limestone globulsion delivery system for deep ocean storage

    Energy Technology Data Exchange (ETDEWEB)

    Swett, P.; Golomb, D.; Barry, E.; Ryan, D.; Lawton, C. [Massachusetts Univ., Lowell, MA (United States)

    2005-07-01

    Ocean storage of carbon dioxide (CO{sub 2}) raises serious environmental, technical and economic problems because a massive point injection of pure liquid CO{sub 2} at depth would create a plume of carbonic acid with a pH lower than 7. Acidified seawater is considered to be harmful to aquatic organisms. Laboratory studies have shown that injecting a globulsion consisting of CO{sub 2}, water (H{sub 2}O) and calcium carbonate (CaCO{sub 3}) instead of pure liquid CO{sub 2} results in an alkaline reaction rather than an acidic reaction. Because calcium carbonate and bicarbonate are natural ingredients of seawater, there is no expected harm due to the additive limestone. This paper presented a practical delivery system for the underwater creation of globulsion. When liquid or supercritical CO{sub 2} is mixed with a slurry of finely pulverized limestone (CaCO{sub 3}) in pure or seawater, a macro-emulsion is formed consisting of CO{sub 2} droplets coated with CaCO{sub 3} particles dispersed in water. In this study, liquid CO{sub 2} was piped to approximately 500 m depth, which is below the flash point of liquid CO{sub 2} into vapor. A slurry of pulverized limestone in seawater was also separately piped to this depth. A static mixer was mounted at the end of the pipes. Liquid CO{sub 2}, along with a slurry of pulverized limestone and ambient seawater were pumped into the mixer by a turbine. The globulsion exited from the other end of the mixer and sank like a dense plume to greater depths while entraining ambient seawater. The CaCO{sub 3}-coated globules precipitated from the neutrally buoyant plume toward the ocean bottom following equilibration. As such, the ocean was not be acidified with this method of CO{sub 2} discharging. It was concluded that even inland seas, such as the Mediterranean and Black Seas, could be considered for sequestration of a CO{sub 2}/H{sub 2}O/CaCO{sub 3} globulsion. Although adding pulverized limestone to liquid CO{sub 2} and the mixing

  9. Micromechanical analysis of porous SMA

    International Nuclear Information System (INIS)

    Sepe, V; Marfia, S; Sacco, E; Auricchio, F

    2015-01-01

    The present paper deals with computational micromechanical analyses of porous shape memory alloy (SMA). Porous SMAs are considered composite materials made of a dense SMA matrix including voids. A three-dimensional constitutive law is presented for the dense SMA able to reproduce the pseudo-elastic as well as the shape memory effects and, moreover, to account for the different elastic properties of the austenite and martensite phases. Furthermore, a numerical procedure is developed and the overall behavior of the porous SMA is recovered studying a representative volume element. Comparisons between the numerical results, recovered using the proposed modeling, and experimental data available in the literature are presented. The case of closed and open porosity is investigated. Parametric studies have been conducted in order to investigate the influence of the porosity, the shape and orientation of the pores on the overall mechanical response and, mainly, on the energy absorption dissipation capability. (paper)

  10. French high level wastes management

    International Nuclear Information System (INIS)

    Gauvenet, A.J.; Sombret, C.G.

    1980-06-01

    The first French spent fuel reprocessing plant went on stream in 1956 at Marcoule. Since then, all French irradiated fuels and some foreign spent fuels have been reprocessed either in this plant or in a subsequent plant built at La Hague. Marcoule is primarily devoted to metallic fuels, and La Hague to oxide fuels. The fission products solutions generated by reprocessing are acid liquids. They are stored on site in double walled stainless steel tanks fitted with a cooling device to deal with thermal release due to radioactive decay. Although these liquids are retrievable and can be transfered from one tank to another, and in spite of the fact that no disturbance such as overheating or leakage has ever occurred, a decision was made to solidify these solutions in order to make interim storage and, later on, ultimate disposal, safer and easier to control. Glass was chosen, because it is a flexible medium to deal with and it answers the quality requirements of ultimate disposal as well as the manufacturing constraints, such as equipment corrosion, volatilization during fabrication, and suitability to casting into canisters

  11. Murder in French criminal law

    Directory of Open Access Journals (Sweden)

    Jovašević Dragan

    2015-01-01

    Full Text Available The most dangerous forms and aspects of violent crime are criminal offences against life and bodily integrity of others, which are generally designated as acts of homicide. The most prominent among these criminal offences is the crime of murder. Due to the significance, legal nature, characteristics and consequences of this criminal act, all contemporary legislations prescribe the most severe measures and types of punishment for the commission of this crime. There are three types of murder: 1 ordinary (common murder, 2 murder committed under mitigating circumstances, and 3 murder committed under aggravating circumstances, which is as a rule punishable by the most severe punishment. All contemporary criminal legislations, including French legislation, recognize various types and forms of murder, depending on the classification criteria. The most prominent forms of murder are those involving various motives that induce the perpetrators to cause death to another person. In this paper, the author examines the concept, contents, characteristics, forms and elements of the crime of murder in French criminal law, discussing the theoretical and practical aspects of this issue.

  12. Effects of Water and Low-Medium Temperature on Limestone from Mt Etna basement

    Science.gov (United States)

    Castagna, Angela; Ougier-Simonin, Audrey; Benson, Philip; Browning, John; Fazio, Marco; Walker, Richard; Vinciguerra, Sergio

    2017-04-01

    Mount Etna volcano, Sicily, sits atop a structurally complex sedimentary basement continuously subjected to tectonic deformation. The flyschoid formations belonging to the Appenninic-Maghrebian Chain (AMC) and making up the accretionary wedge of a regional fold-and-thrust belt lie above carbonate Hyblean Plateau (HP) sequences, belonging to the African plate. Carbonate rocks represent a major component of the sedimentary basement: they are spread throughout the AMC as continuous strata and discontinuous lenses, and are the main constituent (e.g., Comiso Limestone) of the HP foreland. Etna is an active volcanic environment, characterized by complex stress field distributions, magmatic and non-magmatic fluid circulation, and elevated temperature gradients; the edifice has been constructed at various rates and with variable distribution of effusive products. These intrinsic and extrinsic parameters are known to impact the rheological behaviour of rocks. Previous triaxial deformation studies on carbonates (Tavel Limestone, Solnhofen Limestone and Comiso Limestone) have shown the importance of temperature, and the presence of water as pore fluid, on the mechanical strength and failure mode of the rocks. However, to our knowledge, no previous studies have considered the distal heating effect of intrusions on the carbonate mechanical strength from the basement. Here we investigate the behaviour under varying P-T conditions at constant strain rate (10-5 s-1) on both dry and water saturated samples of Comiso Limestone, a low-porosity (10.2% average) carbonate rock belonging to the HP. We ran separate conventional triaxial experiments at various confining effective pressure from 0 up to 50 MPa at room temperature (20°C), in both dry and drained water-saturated conditions, using natural samples, and thermally-treated samples (150°C, 300°C, and 450°C). Acoustic Emissions and P-wave velocities were recorded during the experiments. Sample failure covers the brittle and

  13. Metrology of nanosize biopowders using porous silicon surface

    International Nuclear Information System (INIS)

    Zhuravel', L.V.; Latukhina, N.V.; Pisareva, E.V.; Vlasov, M.Yu.; Volkov, A.V.; Volodkin, B.O.

    2008-01-01

    Powders of hydroxyapatite deposited on porous silicon surface were investigated by TEM and STM methods. Thickness of porous lay was 1-100 micrometers; porous diameter was 0.01-10 micrometers. Images of porous silicon surface with deposited particles give possibility to estimate particles size and induce that only proportionate porous diameter particles have good adhesion to porous silicon surface.

  14. Characteristics of porous zirconia coated with hydroxyapatite

    Indian Academy of Sciences (India)

    However, porous hydroxyapatite bodies are mechanically weak and brittle, which makes shaping and implantation difficult. One way to solve this problem is to introduce a strong porous network onto which hydroxyapatite coating is applied. In this study, porous zirconia and alumina-added zirconia ceramics were prepared ...

  15. Process of preparing tritiated porous silicon

    Science.gov (United States)

    Tam, Shiu-Wing

    1997-01-01

    A process of preparing tritiated porous silicon in which porous silicon is equilibrated with a gaseous vapor containing HT/T.sub.2 gas in a diluent for a time sufficient for tritium in the gas phase to replace hydrogen present in the pore surfaces of the porous silicon.

  16. Porous silicon: X-rays sensitivity

    International Nuclear Information System (INIS)

    Gerstenmayer, J.L.; Vibert, Patrick; Mercier, Patrick; Rayer, Claude; Hyvernage, Michel; Herino, Roland; Bsiesy, Ahmad

    1994-01-01

    We demonstrate that high porosity anodically porous silicon is radioluminescent. Interests of this study are double. Firstly: is the construction of porous silicon X-rays detectors (imagers) possible? Secondly: is it necessary to protect silicon porous based optoelectronic systems from ionising radiations effects (spatial environment)? ((orig.))

  17. The absent father of Sino-French cinema: Contemporary Taiwanese cinema and 1950s French auteurs

    OpenAIRE

    Bloom, ME

    2014-01-01

    © 2014 Taylor & Francis. In contemporary Sino-French cinema, father characters who are dead, long lost or geographically distant leave gaping holes in the lives of the offspring left behind. The absent fathers in Sino-French films by Taiwanese auteurs Cheng Yu-chieh, Hou Hsiao-hsien and Tsai Ming-liang serve as metaphors for French auteurs. French New Wave films constitute the majority of the intertexts; however, early 1950s French cinema and even late nineteenth-century painting reflect th...

  18. Reading Speed of Contracted French Braille

    Science.gov (United States)

    Laroche, Louise; Boule, Jacinthe; Wittich, Walter

    2012-01-01

    This study was designed to address three hypotheses: (1) The reading speed of both readers of French braille and readers of French print will be faster in the silent condition; however, this gain in speed will be larger for print readers; (2) Individuals who acquired braille before age 10 will display faster reading speeds at lower error rates…

  19. Gabonese French Dictionaries: Survey and Perspectives*

    African Journals Online (AJOL)

    Gabonese French Dictionaries: Survey and Perspectives. 257 ... be regarded, according to Gouws (2007: 314), as externally motivated products. .... Fair attention is given to different style or normative levels, i.e. .... differs enough from standard French to be regarded as a new emerging lan- ..... Tous les leaders des par-.

  20. French Romanticism and Napoleon's "Geometric Men."

    Science.gov (United States)

    Cole, Robert A.

    1982-01-01

    French intellectual thought changed during the Napoleonic Era. The effects of the Enlightenment philosophers, the French Revolution, the Industrial Revolution, and Romanticism on the development of Napoleon's philosophical outlook are used to illustrate the changes occurring in France as a whole in the early nineteenth century. (AM)

  1. French Phonology for Teachers: A Programmed Introduction.

    Science.gov (United States)

    Green, Jerald R.; Poulin, Norman A.

    This programed, self-instructional course has the following terminal objectives: (1) to present some notions of the science of linguistics and the major branches of linguistics, (2) to teach the segmental and suprasegmental phonemes of French, (3) to identify the major articulatory problems of French for the native speaker of English, (4) to…

  2. The French Regions and Their Social Health

    Science.gov (United States)

    Jany-Catrice, Florence

    2009-01-01

    In this article, a new indicator designed to capture the multidimensionality of the social health of the French regions is put to the test. Drawing on regional data for 2004, this indicator of social health (ISH) sheds new light on the social performance of the French regions. The worst performers are the highly urbanised regions, whereas others,…

  3. French for Specific Purposes: The Hawaiian Experience.

    Science.gov (United States)

    Benouis, Mustapha

    1986-01-01

    Describes the development of and the reaction to a course in Business French at the University of Hawaii. Its success, coupled with its recognition by state and academic officials, brought about the initiation of similar courses in other languages and the development of French for travel industry management majors. (SED)

  4. French Higher Education: A Cartoon Essay

    Science.gov (United States)

    Hall, Matthew Henry

    2012-01-01

    In this cartoon essay, the author shares his experience from a travel to Paris to see the French higher education system. From his travel, he learned that in France, "degree" inflation may be an issue, but not grade inflation. On the flight home, the author reflects how French and American academics answer one question about the state of…

  5. The French Language in the Americas.

    Science.gov (United States)

    Valdman, Albert, Ed.

    The annual bulletin of the French 8 section of the Annual Meeting of the Modern Language Association of America is presented with the texts of papers read at both the 1969 and 1970 sessions. The 1970 papers, in French, include Jean Louis Darbelnet's "Etude Sociolinguistique des contacts entre 1'Anglais et le Francais au Canada et en…

  6. French Military Adaptation in the Afghan War

    DEFF Research Database (Denmark)

    Schmitt, Olivier

    2017-01-01

    as any to borrow from other countries’ experiences. In order to do so, this article introduces the concept of ‘selective emulation’, and compares the French and German military adaptation processes in Afghanistan. The article argues that there is indeed something distinctive about French military...

  7. French petroleum demand stable since thirteen years

    International Nuclear Information System (INIS)

    Chauvot, M.

    2005-01-01

    The French union of petroleum industries (Ufip) has presented a globally satisfactory status of the French petroleum situation. However, the refining capacities are not always well adapted to the evolution of the demand and the production of diesel fuels remains insufficient while France exports gasoline. Short paper. (J.S.)

  8. Health Information in French (français)

    Science.gov (United States)

    ... Biopsy - français (French) Bilingual PDF Health Information Translations Breast Biopsy - français (French) Bilingual PDF Health Information Translations Colposcopy - français (French) Bilingual PDF ...

  9. Crispy in the french breakfast

    Directory of Open Access Journals (Sweden)

    Alain Drouard

    2003-09-01

    Full Text Available Bien qu’il y ait eu du croquant et du croustillant dans l’alimentation des Français avant l’époque contemporaine (pain, gâteaux, fruits frais ou secs sa place a augmenté récemment à la suite des changements intervenus dans le petit déjeuner. Le but de cet article est d’analyser historiquement la pénétration et la diffusion du croquant et du croustillant dans le petit déjeuner français. Celle ci s’est faite d’abord dans les villes sous l’influence de modèles étrangers et principalement Anglo-Saxons qui font une place importante au croustillant. Les partisans des nouveaux petits déjeuners à base de lait, de céréales et de fruits ne cherchaient pas seulement à promouvoir le végétarisme mais aussi à lutter contre la « dégénérescence » qui menaçait à leurs yeux la société moderne. Après avoir rappelé la naissance du petit déjeuner français, on étudiera le rôle des modèles étrangers dans l’évolution de la consommation d’aliments croustillants.Though crispy items were present in French food before the contemporary period (what with bread, cakes, fresh or dried fruits, they have recently played a more important part as breakfast underwent a series of changes. The aim of this article is to make an historical analysis of the emergence and spread of crispy food in the French breakfast. The influence of foreign and more especially Anglo-Saxon models contributed to increasing its importance. Those who advocated these new breakfasts at the beginning of the XXth century were convinced to fight also against “degeneracy” which they thought was a threat to modern society. I shall first briefly explain how the French breakfast was born, then I shall focus on the influence and impact of foreign models.

  10. Development of Gender Typicality and Felt Pressure in European French and North African French Adolescents.

    Science.gov (United States)

    Hoffman, Adam J; Dumas, Florence; Loose, Florence; Smeding, Annique; Kurtz-Costes, Beth; Régner, Isabelle

    2017-11-14

    Trajectories of gender identity were examined from Grade 6 (M age  = 11.9 years) to Grade 9 in European French (n = 570) and North African French (n = 534) adolescents, and gender and ethnic group differences were assessed in these trajectories. In Grade 6, boys of both ethnic groups reported higher levels of gender typicality and felt pressure for gender conformity than girls. European French girls and boys and North African French girls reported decreasing gender typicality from Grade 6 to Grade 9, whereas North African French boys did not change. Felt pressure decreased among girls, did not change in European French boys, and increased in North African French boys. Ethnic and gender differences in gender identity development are discussed. © 2017 The Authors. Child Development © 2017 Society for Research in Child Development, Inc.

  11. Porous squeeze-film flow

    KAUST Repository

    Knox, D. J.; Wilson, S. K.; Duffy, B. R.; McKee, S.

    2013-01-01

    surface moving under a prescribed constant load and a flat thin porous bed coating a stationary flat impermeable surface is considered. Unlike in the classical case of an impermeable bed, in which an infinite time is required for the two surfaces to touch

  12. On strength of porous material

    DEFF Research Database (Denmark)

    Nielsen, Lauge Fuglsang

    1999-01-01

    The question of non-destructive testing of porous materials has always been of interest for the engineering profession. A number of empirically based MOE-MOR relations between stiffness (Modulus Of Elasticity) and strength (Modulus OF Rupture) of materials have been established in order to control...

  13. Porous Materials - Structure and Properties

    DEFF Research Database (Denmark)

    Nielsen, Anders

    1997-01-01

    The paper presents some viewpoints on the description of the pore structure and the modelling of the properties of the porous building materials. Two examples are given , where it has been possible to connect the pore structure to the properties: Shrinkage of autoclaved aerated concrete...

  14. Porous Concrete and Its Application

    Directory of Open Access Journals (Sweden)

    V. V. Opekunov

    2005-01-01

    Full Text Available Some aspects of resource saving problem in the process of mass construction and operation of heated construction installations are considered in the paper. A special attention is paid to necessary application of porous concrete products in the process of the housing construction. The preference is given to the products made of autoclave cellular concrete and cement hydrophobisized cement perlite concrete.

  15. Constitutive model for porous materials

    International Nuclear Information System (INIS)

    Weston, A.M.; Lee, E.L.

    1982-01-01

    A simple pressure versus porosity compaction model is developed to calculate the response of granular porous bed materials to shock impact. The model provides a scheme for calculating compaction behavior when relatively limited material data are available. While the model was developed to study porous explosives and propellants, it has been applied to a much wider range of materials. The early development of porous material models, such as that of Hermann, required empirical dynamic compaction data. Erkman and Edwards successfully applied the early theory to unreacted porous high explosives using a Gruneisen equation of state without yield behavior and without trapped gas in the pores. Butcher included viscoelastic rate dependance in pore collapse. The theoretical treatment of Carroll and Holt is centered on the collapse of a circular pore and includes radial inertia terms and a complex set of stress, strain and strain rate constitutive parameters. Unfortunately data required for these parameters are generally not available. The model described here is also centered on the collapse of a circular pore, but utilizes a simpler elastic-plastic static equilibrium pore collapse mechanism without strain rate dependence, or radial inertia terms. It does include trapped gas inside the pore, a solid material flow stress that creates both a yield point and a variation in solid material pressure with radius. The solid is described by a Mie-Gruneisen type EOS. Comparisons show that this model will accurately estimate major mechanical features which have been observed in compaction experiments

  16. Additively manufactured porous tantalum implants

    NARCIS (Netherlands)

    Wauthle, Ruben; Van Der Stok, Johan; Yavari, Saber Amin; Van Humbeeck, Jan; Kruth, Jean Pierre; Zadpoor, Amir Abbas; Weinans, Harrie; Mulier, Michiel; Schrooten, Jan

    2015-01-01

    The medical device industry's interest in open porous, metallic biomaterials has increased in response to additive manufacturing techniques enabling the production of complex shapes that cannot be produced with conventional techniques. Tantalum is an important metal for medical devices because of

  17. Stars War in French Gastronomy

    DEFF Research Database (Denmark)

    Gergaud, Olivier; Smeets, Valérie; Warzynski, Frederic

    In this paper, we analyze the careers from a sample of more than 1,000 top French chefs over more than twenty years and link it to the success or reputation of the restaurants where they have worked. This allows us to test what are the determinants of success but also to investigate the dynamics...... of performance and reputation, stressing the importance of the quality of apprenticeships, mentoring and entrepreneurship spirit. We find that the prestige of the restaurant where individuals work is on average declining along the career, and that the quality of apprenticeship is strongly related to the future...... success as chef. We also find that prices of restaurants with higher reputation are more sensitive to bad signals....

  18. Disputing Rossellini: Three French perspectives

    Directory of Open Access Journals (Sweden)

    James Harvey-Davitt

    2014-12-01

    Full Text Available In his burgeoning body of film theoretical work the French philosopher Jacques Rancière repeatedly turns to some canonical films by Neorealist pioneer Roberto Rossellini. Not simply retreading tired motifs of Neorealism, Rancière’s comments offer some profound new insights, revolutionising prior perspectives on Rossellini. In this article I shall put Rancière’s perspective into dialogue with two of the most significant of these perspectives: André Bazin’s and Gilles Deleuze’s. In doing so I shall claim that Rancière’s approach departs radically from the canonised, standardised Neorealist conception of Rossellini. Instead, I wish to claim that he describes a modernist artist primarily concerned with aesthetic clashes. In doing so I shall contemplate how the meaning of these films has evolved since the era of their contemporary reception, demonstrating the congruence and disparity between these three disparate approaches.

  19. Impact of French advertising campaign

    International Nuclear Information System (INIS)

    Chaussade, Jean-Pierre; Ansel, Philippe

    1993-01-01

    'Today, some 75 % of France's electricity is generated by nuclear plants'. This was the theme of the advertising campaign launched for the second time in May 1992 by Electricite de France in national daily newspapers and magazines, in regional publications, on cinema and on TV. Compared to 1991 the second campaign was a new step in communication: first, was the wish to inform better the public. A Minitel program '3614 EDF' was created and connected by general public including a lot of information about nuclear energy and the way to visit a nuclear plant; secondly, was the use of TV media to target a larger population. The TV spot, 'the nuclear drill', uses humor to get more impact on the public. The campaign received an encouraging reception from the press, which admired its boldness and originality. As far as the general public is concerned, the campaign achieved its goals, as illustrated by the results of post-campaign surveys carried out to measure its effect. The segment of population targeted by campaign was mainly the so called 'pragmatics'. 'Pragmatics', who account for 25 % of the French population, are young, have a good education and are well informed. This category was selected as it shows a subtle attitude towards nuclear power, with more doubts than certainties. Moreover, this segment of the population has proven to be open to information issued by EDF and also plays a key role in influencing social trends. 63% of the segment targeted by the campaign (pragmatics) and 56% of the whole french population saw the ads

  20. Reconstruction of three-dimensional porous media using generative adversarial neural networks

    Science.gov (United States)

    Mosser, Lukas; Dubrule, Olivier; Blunt, Martin J.

    2017-10-01

    To evaluate the variability of multiphase flow properties of porous media at the pore scale, it is necessary to acquire a number of representative samples of the void-solid structure. While modern x-ray computer tomography has made it possible to extract three-dimensional images of the pore space, assessment of the variability in the inherent material properties is often experimentally not feasible. We present a method to reconstruct the solid-void structure of porous media by applying a generative neural network that allows an implicit description of the probability distribution represented by three-dimensional image data sets. We show, by using an adversarial learning approach for neural networks, that this method of unsupervised learning is able to generate representative samples of porous media that honor their statistics. We successfully compare measures of pore morphology, such as the Euler characteristic, two-point statistics, and directional single-phase permeability of synthetic realizations with the calculated properties of a bead pack, Berea sandstone, and Ketton limestone. Results show that generative adversarial networks can be used to reconstruct high-resolution three-dimensional images of porous media at different scales that are representative of the morphology of the images used to train the neural network. The fully convolutional nature of the trained neural network allows the generation of large samples while maintaining computational efficiency. Compared to classical stochastic methods of image reconstruction, the implicit representation of the learned data distribution can be stored and reused to generate multiple realizations of the pore structure very rapidly.