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Sample records for crushed rock salt

  1. Crushed Salt Constitutive Model

    Energy Technology Data Exchange (ETDEWEB)

    Callahan, G.D.

    1999-02-01

    The constitutive model used to describe the deformation of crushed salt is presented in this report. Two mechanisms -- dislocation creep and grain boundary diffusional pressure solution -- are combined to form the basis for the constitutive model governing the deformation of crushed salt. The constitutive model is generalized to represent three-dimensional states of stress. Upon complete consolidation, the crushed-salt model reproduces the Multimechanism Deformation (M-D) model typically used for the Waste Isolation Pilot Plant (WIPP) host geological formation salt. New shear consolidation tests are combined with an existing database that includes hydrostatic consolidation and shear consolidation tests conducted on WIPP and southeastern New Mexico salt. Nonlinear least-squares model fitting to the database produced two sets of material parameter values for the model -- one for the shear consolidation tests and one for a combination of the shear and hydrostatic consolidation tests. Using the parameter values determined from the fitted database, the constitutive model is validated against constant strain-rate tests. Shaft seal problems are analyzed to demonstrate model-predicted consolidation of the shaft seal crushed-salt component. Based on the fitting statistics, the ability of the model to predict the test data, and the ability of the model to predict load paths and test data outside of the fitted database, the model appears to capture the creep consolidation behavior of crushed salt reasonably well.

  2. Thermophysical properties of reconsolidating crushed salt.

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    Bauer, Stephen J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Urquhart, Alexander [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-03-01

    Reconsolidated crushed salt is being considered as a backfilling material placed upon nuclear waste within a salt repository environment. In-depth knowledge of thermal and mechanical properties of the crushed salt as it reconsolidates is critical to thermal/mechanical modeling of the reconsolidation process. An experimental study was completed to quantitatively evaluate the thermal conductivity of reconsolidated crushed salt as a function of porosity and temperature. The crushed salt for this study came from the Waste Isolation Pilot Plant (WIPP). In this work the thermal conductivity of crushed salt with porosity ranging from 1% to 40% was determined from room temperature up to 300°C, using two different experimental methods. Thermal properties (including thermal conductivity, thermal diffusivity and specific heat) of single-crystal salt were determined for the same temperature range. The salt was observed to dewater during heating; weight loss from the dewatering was quantified. The thermal conductivity of reconsolidated crushed salt decreases with increasing porosity; conversely, thermal conductivity increases as the salt consolidates. The thermal conductivity of reconsolidated crushed salt for a given porosity decreases with increasing temperature. A simple mixture theory model is presented to predict and compare to the data developed in this study.

  3. Crushed-salt constitutive model update

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    Callahan, G.D.; Loken, M.C.; Mellegard, K.D. [RE/SPEC Inc., Rapid City, SD (United States); Hansen, F.D. [Sandia National Labs., Albuquerque, NM (United States)

    1998-01-01

    Modifications to the constitutive model used to describe the deformation of crushed salt are presented in this report. Two mechanisms--dislocation creep and grain boundary diffusional pressure solutioning--defined previously but used separately are combined to form the basis for the constitutive model governing the deformation of crushed salt. The constitutive model is generalized to represent three-dimensional states of stress. New creep consolidation tests are combined with an existing database that includes hydrostatic consolidation and shear consolidation tests conducted on Waste Isolation Pilot Plant and southeastern New Mexico salt to determine material parameters for the constitutive model. Nonlinear least-squares model fitting to data from the shear consolidation tests and a combination of the shear and hydrostatic consolidation tests produced two sets of material parameter values for the model. The change in material parameter values from test group to test group indicates the empirical nature of the model but demonstrates improvement over earlier work with the previous models. Key improvements are the ability to capture lateral strain reversal and better resolve parameter values. To demonstrate the predictive capability of the model, each parameter value set was used to predict each of the tests in the database. Based on the fitting statistics and the ability of the model to predict the test data, the model appears to capture the creep consolidation behavior of crushed salt quite well.

  4. Transient convergence and compaction of crushed salt as incorporated in the computer code EMOS

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    Heijdra, J.J.; Hamilton, L.F.M.; Prij, J.; Slagter, W.

    1995-11-01

    An improved model for description of the transient convergence of cavities in rock salt, together with an improved model for the compaction of crushed salt is introduced. The covergence model is based on solutions of the analytical expressions based on secondary creep for a cylindrical and spherical cavity in rock salt. For the model for compaction of crushed salt the relations based on theoretical micro mechanisms have been fitted to laboratory results. A description is given of how the improved models are incorporated into the program EMOS. (orig.).

  5. Rock Crushing Using Microwave Pre-Treatment

    KAUST Repository

    Kim, Seunghee

    2016-08-11

    Crushing and grinding are primary contributors to a high energy demand in the mining industry, yet, both are surprisingly inefficient processes, often with efficiencies as low as 1%. We analyze size reductions during crushing and grinding operations and explore the potential of multiplying internal weaknesses in rock materials by non-mechanical means. In particular, when rock blocks (wet or even dry if polycrystalline) are exposed to microwaves, internal cracks can develop along grain boundaries via differential thermal expansion between grains and volumetric thermal expansion of water in pores. Brazilian tests conducted on granite and cement mortar specimens show that the tensile strength decreases proportional to the duration of microwave treatment. Thermal changes, excessive fluid pressure buildup and induced stresses are analyzed in the context of hydro-Thermo-mechanically coupled processes. Results confirm that both differential thermal expansion of mineral grains and volumetric thermal expansion of water can generate cracks upon microwave exposure. Optimal conditions are suggested to lower the combined consumption of electric and mechanical energy.

  6. A dynamic ball compression test for understanding rock crushing.

    Science.gov (United States)

    Huang, S; Liu, H; Xia, K

    2014-12-01

    During crushing, rock particles are subjected to complicated loading. It is desired to establish the relation between the loading and the fragmentation parameters for better understanding rock crushing mechanism. In this work, a split Hopkinson pressure bar system in combination with high speed cameras is utilized in the dynamic ball compression test, in which the spherical rock sample is adopted to avoid the shape effect. Using elasticity theory, the loading rate and the dynamic indirect tensile strength are first calculated. With the aid of the moment-trap technique and high speed cameras, the surface energy is determined for each sample. The relations between the loading rate and the fragmentation parameters, i.e., the number of fragments and the surface energy are established. The application of this method to a granitic rock shows that it is flexible and can be applied to the crushing study of generic brittle solids.

  7. Numerical modeling of macroscale brittle rock crushing during impacts

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    Badr, Salah A.; Abdelhaffez, Gamal S. [King Abdulaziz Univ., Jeddah (Saudi Arabia)

    2014-02-01

    Several machines, such as crushers use the physical effect of compression to cause fragmentation 'crushing' of brittle rocks. As a consequence of the complex fragmentation process, crushers are still sized by empirical approaches. This paper present the results of a numerical study to understand some aspects of rock crushing phenomenon in terms of energy consumption. The study uses the discrete element approach of PFC2D code to simulate a stamp mill. The stamp mill has a simple crushing mechanism of a fixed kinetic energy delivered by a rigid ram impact. A single rock fragment crushing process dependent on the number of stamp mill ram blows is numerically examined. Both amount and type of energy generated by a ram blow are monitored besides the type of fractures generated. The model results indicate that the ram impact energy is mainly consumed in form of friction energy (up to 61 %) while strain energy stays at about 5 % of delivered energy. The energy consumed by crushing the rock represents only 32 % to 45 % of stamp mill energy and tends to decrease as the number of impacts increases. The rock fragmented matrix tends to convert into more friction energy with reduced number of new fractures as number of blows increase. The fragmentation caused by tensile is more often compared to those caused by shear, this behaviour increased with increasing number of ram blows. (orig.)

  8. Diffusion in the pore water of compacted crushed salt

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    Fluegge, Judith; Herr, Sebastian; Lauke, Thomas; Meleshyn, Artur; Miehe, Ruediger; Ruebel, Andre

    2016-07-15

    Diffusion of dissolved radionuclides in the pore water of compacted crushed salt in the long-term is the most relevant process for the release of radionuclides from a dedicated repository for high-level waste in a salt formation as has been shown in latest safety assessments and research projects /BUH 16/. So far, diffusion coefficients for free water have been applied for the diffusion in pore water in models for long-term safety assessments. This conservative assumption was used, because data on the diffusion coefficient of dissolved substances in crushed salt have been missing. Furthermore, the diffusion coefficient in the pore water was assumed to be constant and independent from the degree of compaction of the crushed salt. The work presented in this report was intended to contribute to fill this gap of knowledge about how the diffusion of radionuclides takes place in the compacted backfill of a repository in salt. For the first time, the pore diffusion coefficient as well as its dependence on the porosity of the crushed salt was determined experimentally by means of through-diffusion experiments using caesium as tracer. The results achieved in this project suggest that the diffusion in compacted crushed salt is not fully comparable to that in a homogeneous, temporally stable porous medium like sand or clay. The results obtained from four diffusion experiments show a remarkably different behaviour and all yield unique concentration versus time plots which includes highly temporal variable tracer fluxes with even full interruptions of the flux for longer periods of time. This effect cannot be explained by assuming a tracer transport by diffusion in a temporarily invariant pore space and / or under temporally invariant experimental conditions. From our point of view, a restructuring of the pore space seems to lead to closed areas of pore water in the sample which may open up again after some time, leading to a variable pore space and hence variable diffusive

  9. Evaluation of potential crushed-salt constitutive models

    Energy Technology Data Exchange (ETDEWEB)

    Callahan, G.D.; Loken, M.C.; Sambeek, L.L. Van; Chen, R.; Pfeifle, T.W.; Nieland, J.D. [RE/SPEC Inc., Rapid City, SD (United States); Hansen, F.D. [Sandia National Labs., Albuquerque, NM (United States). Repository Isolation Systems Dept.

    1995-12-01

    Constitutive models describing the deformation of crushed salt are presented in this report. Ten constitutive models with potential to describe the phenomenological and micromechanical processes for crushed salt were selected from a literature search. Three of these ten constitutive models, termed Sjaardema-Krieg, Zeuch, and Spiers models, were adopted as candidate constitutive models. The candidate constitutive models were generalized in a consistent manner to three-dimensional states of stress and modified to include the effects of temperature, grain size, and moisture content. A database including hydrostatic consolidation and shear consolidation tests conducted on Waste Isolation Pilot Plant and southeastern New Mexico salt was used to determine material parameters for the candidate constitutive models. Nonlinear least-squares model fitting to data from the hydrostatic consolidation tests, the shear consolidation tests, and a combination of the shear and hydrostatic tests produces three sets of material parameter values for the candidate models. The change in material parameter values from test group to test group indicates the empirical nature of the models. To evaluate the predictive capability of the candidate models, each parameter value set was used to predict each of the tests in the database. Based on the fitting statistics and the ability of the models to predict the test data, the Spiers model appeared to perform slightly better than the other two candidate models. The work reported here is a first-of-its kind evaluation of constitutive models for reconsolidation of crushed salt. Questions remain to be answered. Deficiencies in models and databases are identified and recommendations for future work are made. 85 refs.

  10. Rock salt constitutive modeling

    Energy Technology Data Exchange (ETDEWEB)

    Nickell, R.E.

    1980-03-18

    The Serata model is the best operational model available today because it incorporates: (1) a yield function to demarcate between viscoelastic and viscoplastic behavior of rock salt; (2) a pressure and temperature dependence for yield stresses; and (3) a standard linear solid, which can be readily extended into the non-linear regime, to represent creep behavior. Its only deficiencies appear to be the lack of secondary creep behavior (a free dashpot) and some unsettling arbitrariness about the Poisson's ratio (..nu.. ..-->.. 0.5) argument for viscoplasticity. The Sandia/WIPP model will have good primary and secondary creep capability, but lacks the viscoplastic behavior. In some cases, estimated inelastic strains may be underpredicted. If a creep acceleration mechanism associated with brine inclusions is observed, this model may require extensive revision. Most of the other models available (SAI, RE-SPEC, etc.) are only useful for short-term calculations, because they employ temporal power law (t/sup n/) primary creep representations. These models are unsatisfactory because they cannot represent dual mechanisms with differing characteristic times. An approach based upon combined creep and plasticity is recommended in order to remove the remaining deficiency in the Serata model. DOE/Sandia/WIPP should be encouraged to move aggressively in this regard.

  11. Cooling Effect of Crushed Rock-Based Embankment along the Chaidaer-Muli Railway

    Directory of Open Access Journals (Sweden)

    Ji Chen

    2015-01-01

    Full Text Available This paper presents an experimental study of the cooling effect of crushed rock-based embankment on slope wetlands along the Chaidaer-Muli Railway. The result shows that only the embankment shady side can be effectively cooled down in a warm permafrost region and the crushed rock-based embankment can cool the entire embankment in a cold permafrost region. The crushed rock-based embankment cannot eliminate the problems from the south-north slope. Slope wetland can influence the temperature field of the crushed rock-based embankment. On the uphill side, it will lead to degradation in some cases and development of permafrost in other cases, which depends on the topsoil water content and ground surface runoff. On the downhill side, it always leads to the warming of permafrost. For crushed rock-based embankment constructed on slope wetlands, it is necessary to adopt other stronger measures to eliminate the sunny-shady slope problems.

  12. Crystal plasticity and grain crushing in high-porosity rocks

    Science.gov (United States)

    Rahmani, H.; Tjioe, M.; Borja, R. I.

    2012-12-01

    Previous studies show the significance of considering microstructure of individual crystals in modeling the inelastic behavior of high-porosity rocks. Plastic deformation of high-porosity crystalline rocks, exemplified by limestone, is mainly attributed to crystal plasticity and cataclastic flow. Crystal plasticity is defined as the plastic deformation along potential slip systems within the crystal lattice. In the context of continuum mechanics this micro-mechanism is modeled by a nonlinear relationship between stresses and strains. Two types of nonlinearity characterize the inelastic behavior of the crystal grains: material nonlinearity and geometric nonlinearity. Material nonlinearity defines the changes in stiffness matrix due to plastic slip along slip systems. Geometric nonlinearity contributes to the changes in stiffness matrix due to changes in the geometry of the crystal grains. Geometric nonlinearity is modeled using theory of finite deformation, which assumes the geometry of slip systems to be a function of crystal deformation. This type of nonlinearity is very important in modeling crystal deformation mainly because of plastic spin induced by anisotropy in the crystal structure. However, considering the geometry of slip systems as a function of crystal slip makes the equations highly nonlinear. As a result, many studies either ignore geometric nonlinearity or make other assumptions to simplify the equations. Cataclastic flow, on the other hand, is characterized by pervasive grain crushing in which larger grains are converted into smaller ones. We model cataclastic flow as strong discontinuity in the grain scale via an assumed enhanced strain method formulated within the context of nonlinear finite elements. The method allows the individual finite elements, identified to be in critical condition, to break into two pieces along a plane identified by theory of bifurcation. We show that modeling cataclastic flow combined with finite deformation crystal

  13. The cooling effect of crushed rock structures on permafrost under an embankment

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Based on the analysis and comparison of soil temperature, thermal regime and permafrost table under the experimental embankment of crushed rock structures in Beiluhe, results show that crushed rock structures provide an extensive cooling effect, which produces a rising permafrost table and decreasing soil temperatures. The rise of the permafrost table under the embankment ranges from an increase of 1.08 m to 1.67 m, with an average of 1.27 m from 2004 to 2007. Mean annual soil temperatures under the crushed rock layer embankment decreased significantly from 2005 to 2007, with average decreases of ?1.03 °C at the depth of 0.5 m, ?1.14 °C at the depth of 1.5 m, and ?0.5 °C at the depth of 5 m. During this period, mean annual soil temperatures under the crushed rock cover embankment showed a slight decrease at shallow depths, with an average decrease of ?0.2 °C at the depth of 0.5 m and 1.5 m, but a slight rise at the depth of 5 m. After the crushed rock structures were closed or crammed with sand, the cooling effect of the crushed rock layer embankment was greatly reduced and that of the crushed rock cover embankment was just slightly reduced.

  14. Permeability to brine of crushed salt rock for waste isolation, considering long-term pressure variation of overlying strata and dissolution processes. Final report; Durchlaessigkeitsverhalten von Steinsalzversatz gegenueber Laugen unter Beruecksichtigung von zeitlich veraenderlichen Ueberlagerungsdruecken und Loesungsvorgaengen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Froehlich, H. [Battelle Ingenieurtechnik GmbH, Eschborn (Germany); Conen, O. [Technische Univ. Darmstadt (Germany); Haefner, F.; Bruck, J. v. der [Technische Univ. Bergakademie Freiberg (Germany)

    1999-07-01

    It cannot be excluded that there will be ingress of brines to underground isolation plants for nuclear and chemical toxic wastes. The transport mechanisms in the waste repository are much determined by the perviousness of the backfilling and the sealing material used after waste emplacement in salt rock mine shafts. The critical quantity is the permeability, both for inflow of brine into the bedded waste areas, and for contaminated brine squeeze-out mechanisms. The project research work was to establish the mass transfer parameters for calculating the transport mechanisms in backfilled and sealed shafts. Using near-reality simulation of conditions, the time-dependent influence of pressure variations of overlying strata, humidity and salt/brine interactions on the permeability was examined and quantified. (orig./CB) [German] In Endlagern fuer nukleare und chemotoxische Abfaelle im Salinar kann der Zutritt von Laugen nicht prinzipiell ausgeschlossen werden. Die Transportvorgaenge innerhalb des Endlagers werden wesentlich von der Durchlaessigkeit der Versatzmaterialien und der Verschluesse bestimmt. Die bestimmende Groesse, sowohl fuer den Laugenzufluss in die Einlagerungsbereiche als auch fuer das Auspressen kontaminierter Lauge aus dem Endlager, ist dabei die Permeabilitaet. Ziel der hier vorgestellten Arbeiten war es, Stofftransportparameter fuer die Berechnung von Ausbreitungsvorgaengen in den verfuellten Bereichen eines salinaren Endlagers bereitzustellen. Unter Simulation realitaetsnaher Bedingungen wurde der Einfluss von zeitabhaengigem Ueberlagerungsdruck (Gebirgsdruck), Feuchte und die Wechselwirkung von Salz/Lauge auf das Durchlaessigkeitsverhalten untersucht und quantifiziert. (orig.)

  15. IMPACT OF ROCK HARDNESS ON FRAGMENTATION BY HYDRAULIC HAMMER AND CRUSHING IN JAW CRUSHER

    Directory of Open Access Journals (Sweden)

    Trpimir Kujundžić

    2008-12-01

    Full Text Available The physical and mechanical characteristics of intact rocks depend on the way of their formation, sustained deformations and the process of wearing a specific rock has been exposed to. These characteristics have a rather high influence on the technological process of extraction and dressing of mineral raw materials. However, the mechanical characteristics of rocks due to use of explosives for their extraction in the open pit have a more significant impact. The rock blocks extracted by blasting which are larger than the opening of the primary crusher are usually fragmented by hydraulic hammer. The paper presents the results of the testing of impact of rock hardness on fragmentation of rocks by means of hydraulic hammer and during crushing in jaw crusher. The testing was carried out on the rock samples from five quarries. According to the obtained results the hardness has a considerably larger impact on the fragmentation energy by hydraulic hammer than on the crushing energy in jaw crusher.

  16. Behavior of crushed rock aggregates used in road construction exposed to cold climate conditions

    Science.gov (United States)

    Kuznetsova, Elena; Pérez Fortes, Ana Patricia; Anastasio, Sara; Willy Danielsen, Svein

    2016-04-01

    carried out in both countries. The use of crushed aggregates in both the frost protection layer and asphalt layers is the main topic for our investigations. In existing standards there is large focus on mechanical properties of aggregates and their grain size distribution, but little focus on mineralogy and and its behaviour at low temperatures. With the purpose to study the effect of winter climatic conditions and the use of salts during winter maintenance, different samples of aggregates and asphalt mixtures used in Norwegian and Spanish roads were subjected to freeze-thaw cycles in the laboratory. To evaluate the impact of these cycles to the mechanical properties of the selected materials, Los Angeles test on aggregates and Cantabro test on asphalt have been done and compared with results from the same aggregates and asphalt mixtures but untreated in the laboratory. The results obtained were related to the petrographical analysis of the rocks that compose the aggregates in order to estimate the influence of the rock properties (mineralogy, texture and structure) in road materials behavior, especially when they are exposed to winter conditions.

  17. Study of the fracture behavior of mortar and concretes with crushed rock or pebble aggregates

    Directory of Open Access Journals (Sweden)

    Sebastião Ribeiro

    2011-03-01

    Full Text Available The objective of this work was to compare the fracture energy of mortar and concretes produced with crushed rock and pebble aggregates using zero, 10, 20, 30 and 40% of aggregates mixed with standard mortar and applying the wedge splitting method to achieve stable crack propagation. The samples were cast in a special mold and cured for 28 days, after which they were subjected to crack propagation tests by the wedge splitting method to determine the fracture energies of the mortar and concrete. The concretes showed higher fracture energy than the mortar, and the concretes containing crushed rock showed higher resistance to crack propagation than all the compositions containing pebbles. The fracture energy varied from 38 to 55 J.m-2. A comparison of the number of aggregates that separated from the two concrete matrices with the highest fracture energies indicated that the concrete containing pebbles crumbled more easily and was therefore less resistant to crack propagation.

  18. Research on the mechanisms of EME and charge accumulation during the rock crush

    Institute of Scientific and Technical Information of China (English)

    SU Wei-jia; LI Yan-ming

    2008-01-01

    The phenomenon of EME and charge accumulation were included during the load-bearing failure processing of the rock. The mechanism and signal law of the two kinds of phenomenon through the experiment, as well as the mutual relation of the two kinds of phenomenon, were contribute to monitor the regulation of the mine rock and prevent the dynamic disasters of the mine. There were two charge sensors, one electromagnetic radiated sensors and one pressure sensor in the experiment to detect the EME signal and the charge intensity signal during the load-bearing failure processing of the rock.The results show that the charge intensity signal is prior to the EME signal through the date processing and numerical analysis. The two signals change obviously before the rock crush. The two kinds of phenomenon are homogenous and have obvious master-slave characteristic. With the appeared of the EME signal, the charge intensity signal decreased,the power is released.

  19. Nonlinear Analysis of Cavities in Rock Salt

    DEFF Research Database (Denmark)

    Ottosen, N. S.; Krenk, Steen

    1979-01-01

    The paper covers some material and computational aspects of the rock mechanics of leached cavities in salt. A material model is presented in which the instantaneous stiffness of the salt is obtained by interpolation between the unloaded state and a relevant failure state. The model enables predic...

  20. Rheology of rock salt for salt tectonics modeling

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    Shi-Yuan Li

    2016-10-01

    Full Text Available Abstract Numerical modeling of salt tectonics is a rapidly evolving field; however, the constitutive equations to model long-term rock salt rheology in nature still remain controversial. Firstly, we built a database about the strain rate versus the differential stress through collecting the data from salt creep experiments at a range of temperatures (20–200 °C in laboratories. The aim is to collect data about salt deformation in nature, and the flow properties can be extracted from the data in laboratory experiments. Moreover, as an important preparation for salt tectonics modeling, a numerical model based on creep experiments of rock salt was developed in order to verify the specific model using the Abaqus package. Finally, under the condition of low differential stresses, the deformation mechanism would be extrapolated and discussed according to microstructure research. Since the studies of salt deformation in nature are the reliable extrapolation of laboratory data, we simplified the rock salt rheology to dislocation creep corresponding to power law creep (n = 5 with the appropriate material parameters in the salt tectonic modeling.

  1. Sealing performance of bentonite and bentonite/crushed rock borehole plugs

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    Ouyang, S.; Daemen, J.J.K. [Arizona Univ., Tucson, AZ (United States). Dept. of Mining and Geological Engineering

    1992-07-01

    This study includes a systematic investigation of the sealing performance of bentonite and bentonite/crushed rock plugs. American Colloid C/S granular bentonite and crushed Apache Leap tuff have been mixed to prepare samples for laboratory flow testing. Bentonite weight percent and crushed tuff gradation are the major variables studied. The sealing performance assessments include high injection pressure flow tests, polyaxial flow tests, high temperature flow tests, and piping tests. The results indicate that a composition to yield a permeability lower than 5 {times} 10{sup {minus}8} cm/s would have at least 25% bentonite by weight mixed with well-graded crushed rock. Hydraulic properties of the mixture plugs may be highly anisotropic if significant particle segregation occurs during sample installation and compaction. Temperature has no significant effect on the sealing performance within the test range from room temperature to 600{degree}C. Piping damage to the sealing performance is small if the maximum hydraulic gradient does not exceed 120 and 280 for samples with a bentonite content of 25 and 35%, respectively. The hydraulic gradients above which flow of bentonite may take place are deemed critical. Analytical work includes the introduction of bentonite occupancy percentage and water content at saturation as two major parameters for plug design. A permeability model is developed for the prediction of permeability in clays, especially in view of the difficulties in obtaining this property experimentally. A piping model is derived based on plastic flow theory. This piping model permits the estimation of critical hydraulic gradients at which flow of bentonite takes place. The model can also be used to define the maximum allowable pore diameter of a protective filter layer.

  2. Percolation and Physical Properties of Rock Salt

    Science.gov (United States)

    Ghanbarzadeh, S.; Hesse, M. A.; Prodanovic, M.

    2015-12-01

    Textural equilibrium controls the distribution of the liquid phase in many naturally occurring porous materials such as partially molten rocks and alloys, salt-brine and ice-water systems. In these materials, pore geometry evolves to minimize the solid-liquid interfacial energy while maintaining a constant dihedral angle, θ, at solid-liquid contact lines. A characteristic of texturally equilibrated porous media, in the absence of deformation, is that the pore network percolates at any porosity for θ60°. However, in ductile polycrystalline materials including rock salt, the balance between surface tension and ductile deformation controls the percolation of fluid pockets along grain corners and edges. Here we show sufficiently rapid deformation can overcome this threshold by elongating and connecting isolated pores by examining a large number of accessible salt samples from deep water Gulf of Mexico. We first confirm the percolation threshold in static laboratory experiments on synthetic salt samples with X-ray microtomography. We then provide field evidence on existence of interconnected pore space in rock salt in extremely low porosities, significantly below the static percolation threshold. Scaling arguments suggest that strain rates in salt are sufficient to overcome surface tension and may allow percolation. We also present the first level-set computations of three-dimensional texturally equilibrated melt networks in realistic rock fabrics. The resulting pore space is used to obtain the effective physical properties of rock, effective electrical conductivity and mechanical properties, with a novel numerical model.

  3. Influence of variables on the consolidation and unconfined compressive strength of crushed salt: Technical report

    Energy Technology Data Exchange (ETDEWEB)

    Pfeifle, T.W.; Senseny, P.E.; Mellegard, K.D.

    1987-01-01

    Eight hydrostatic compression creep tests were performed on crushed salt specimens fabricated from Avery Island dome salt. Following the creep test, each specimen was tested in unconfined compression. The experiments were performed to assess the influence of the following four variables on the consolidation and unconfined strength of crushed salt: grain size distribution, temperature, time, and moisture content. The experiment design comprised a half-fraction factorial matrix at two levels. The levels of each variable investigated were grain size distribution, uniform-graded and well-graded (coefficient of uniformity of 1 and 8); temperature 25/sup 0/C and 100/sup 0/C; time, 3.5 x 10/sup 3/s and 950 x 10/sup 3/s (approximately 60 minutes and 11 days, respectively); and moisture content, dry and wet (85% relative humidity for 24 hours). The hydrostatic creep stress was 10 MPa. The unconfined compression tests were performed at an axial strain rate of 1 x 10/sup -5/s/sup -1/. Results show that the variables time and moisture content have the greatest influence on creep consolidation, while grain size distribution and, to a somewhat lesser degree, temperature have the greatest influence on total consolidation. Time and moisture content and the confounded two-factor interactions between either grain size distribution and time or temperature and moisture content have the greatest influence on unconfined strength. 7 refs., 7 figs., 11 tabs.

  4. Optimum crushing level of blasted rock at the Prokop'evsk surface coal mine

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    Gemba, V.I.; Starkov, V.L.; Ustyuzhanin, V.S.

    1987-06-01

    Explains that improving the quality of rock crushing using blasting energy increases the efficiency of excavators and other mining equipment, reduces the energy required for scooping and loading tasks and hence reduces the cost of excavating and transporting rock. Investigations performed in surface mines in the Southern Urals and the Kuzbass coal sections showed that changing the mean linear dimensions of the lumps of blasted rock from 0.2 to 0.8 m increased the power consumption of a EhKG-4,6 excavator from 0.12 to 0.3 kWh/m/sup 3/ and that of loading from 0.1 to 1.56 kWh/m/sup 3/. Uses actual values for the efficiency and costs of blasting, excavation and transporting operations (presented in tabular form) as the basis for a comparative evaluation with the aim of determining how to achieve maximum cost-efficiency and, taking all factors into account, calculates that for the Prokop'evsk surface mine the optimum lump size is 0.4 m.

  5. Concepts and Technologies for Radioactive Waste Disposal in Rock Salt

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    Wernt Brewitz

    2007-01-01

    Full Text Available In Germany, rock salt was selected to host a repository for radioactive waste because of its excellent mechanical properties. During 12 years of practical disposal operation in the Asse mine and 25 years of disposal in the disused former salt mine Morsleben, it was demonstrated that low-level wastes (LLW and intermediate-level wastes (ILW can be safely handled and economically disposed of in salt repositories without a great technical effort. LLW drums were stacked in old mining chambers by loading vehicles or emplaced by means of the dumping technique. Generally, the remaining voids were backfilled by crushed salt or brown coal filter ash. ILW were lowered into inaccessible chambers through a borehole from a loading station above using a remote control.Additionally, an in-situ solidification of liquid LLW was applied in the Morsleben mine. Concepts and techniques for the disposal of heat generating high-level waste (HLW are advanced as well. The feasibility of both borehole and drift disposal concepts have been proved by about 30 years of testing in the Asse mine. Since 1980s, several full-scale in-situ tests were conducted for simulating the borehole emplacement of vitrified HLW canisters and the drift emplacement of spent fuel in Pollux casks. Since 1979, the Gorleben salt dome has been investigated to prove its suitability to host the national final repository for all types of radioactive waste. The “Concept Repository Gorleben” disposal concepts and techniques for LLW and ILW are widely based on the successful test operations performed at Asse. Full-scale experiments including the development and testing of adequate transport and emplacement systems for HLW, however, are still pending. General discussions on the retrievability and the reversibility are going on.

  6. Experimental investigation of two-phase flow in rock salt

    Energy Technology Data Exchange (ETDEWEB)

    Malama, Bwalya [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Howard, Clifford L. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

    2014-07-01

    This Test Plan describes procedures for conducting laboratory scale flow tests on intact, damaged, crushed, and consolidated crushed salt to measure the capillary pressure and relative permeability functions. The primary focus of the tests will be on samples of bedded geologic salt from the WIPP underground. However, the tests described herein are directly applicable to domal salt. Samples being tested will be confined by a range of triaxial stress states ranging from atmospheric pressure up to those approximating lithostatic. Initially these tests will be conducted at room temperature, but testing procedures and equipment will be evaluated to determine adaptability to conducting similar tests under elevated temperatures.

  7. Experimental Investigation of Two-Phase Flow in Rock Salt

    Energy Technology Data Exchange (ETDEWEB)

    Malama, Bwalya; Howard, Clifford L.

    2014-07-01

    This Test Plan describes procedures for conducting laboratory scale flow tests on intact, damaged, crushed, and consolidated crushed salt to measure the capillary pressure and relative permeability functions. The primary focus of the tests will be on samples of bedded geologic salt from the WIPP underground. However, the tests described herein are directly applicable to domal salt. Samples being tested will be confined by a range of triaxial stress states ranging from atmospheric pressure up to those approximating lithostatic. Initially these tests will be conducted at room temperature, but testing procedures and equipment will be evaluated to determine adaptability to conducting similar tests under elevated temperatures.

  8. A numerical test method of California bearing ratio on graded crushed rocks using particle flow modeling

    Directory of Open Access Journals (Sweden)

    Yingjun Jiang

    2015-04-01

    Full Text Available In order to better understand the mechanical properties of graded crushed rocks (GCRs and to optimize the relevant design, a numerical test method based on the particle flow modeling technique PFC2D is developed for the California bearing ratio (CBR test on GCRs. The effects of different testing conditions and micro-mechanical parameters used in the model on the CBR numerical results have been systematically studied. The reliability of the numerical technique is verified. The numerical results suggest that the influences of the loading rate and Poisson's ratio on the CBR numerical test results are not significant. As such, a loading rate of 1.0–3.0 mm/min, a piston diameter of 5 cm, a specimen height of 15 cm and a specimen diameter of 15 cm are adopted for the CBR numerical test. The numerical results reveal that the CBR values increase with the friction coefficient at the contact and shear modulus of the rocks, while the influence of Poisson's ratio on the CBR values is insignificant. The close agreement between the CBR numerical results and experimental results suggests that the numerical simulation of the CBR values is promising to help assess the mechanical properties of GCRs and to optimize the grading design. Besides, the numerical study can provide useful insights on the mesoscopic mechanism.

  9. Fracture and Healing of Rock Salt Related to Salt Caverns

    Energy Technology Data Exchange (ETDEWEB)

    Chan, K.S.; Fossum, A.F.; Munson, D.E.

    1999-03-01

    In recent years, serious investigations of potential extension of the useful life of older caverns or of the use of abandoned caverns for waste disposal have been of interest to the technical community. All of the potential applications depend upon understanding the reamer in which older caverns and sealing systems can fail. Such an understanding will require a more detailed knowledge of the fracture of salt than has been necessary to date. Fortunately, the knowledge of the fracture and healing of salt has made significant advances in the last decade, and is in a position to yield meaningful insights to older cavern behavior. In particular, micromechanical mechanisms of fracture and the concept of a fracture mechanism map have been essential guides, as has the utilization of continuum damage mechanics. The Multimechanism Deformation Coupled Fracture (MDCF) model, which is summarized extensively in this work was developed specifically to treat both the creep and fracture of salt, and was later extended to incorporate the fracture healing process known to occur in rock salt. Fracture in salt is based on the formation and evolution of microfractures, which may take the form of wing tip cracks, either in the body or the boundary of the grain. This type of crack deforms under shear to produce a strain, and furthermore, the opening of the wing cracks produce volume strain or dilatancy. In the presence of a confining pressure, microcrack formation may be suppressed, as is often the case for triaxial compression tests or natural underground stress situations. However, if the confining pressure is insufficient to suppress fracture, then the fractures will evolve with time to give the characteristic tertiary creep response. Two first order kinetics processes, closure of cracks and healing of cracks, control the healing process. Significantly, volume strain produced by microfractures may lead to changes in the permeability of the salt, which can become a major concern in

  10. Chemical analysis of the Assale (Ethiopia) rock salt deposit | Binega ...

    African Journals Online (AJOL)

    Chemical analysis of the Assale (Ethiopia) rock salt deposit. ... Log in or Register to get access to full text downloads. ... in common and table salt set by the Ethiopian Quality and Standards Authority. However, during excavation together with the rock salt some soil, mud and other contaminants are found that require further ...

  11. Diagnosis of the rock crushing modes to increase the efficiency of one-roll crusher operation

    Science.gov (United States)

    Nikitin, A. G.; Laktionov, S. A.; Medvedeva, K. S.

    2017-09-01

    In the paper the hypotheses of destruction of brittle materials are given, as well as the analysis of energy costs for crushing. The methods of crushing are considered and a comparative analysis of their energy capacity and quality of the product is carried out. The parameters of the crushing process are determined from the point of view of their productivity and, accordingly, their energy efficiency. It is shown that the process of crushing in the one-roll crushers is due to the frictional forces acting between the surfaces of the roll and a piece of the crushed material, and also between the piece and the immovable jaw. The comparison of initial sizes of the crushed pieces in the crushes with the vertical and inclined surfaces of immovable jaw, which shows that with the increase in the bend angle of the immovable jaw the degree of crushing increases. Based on the analysis of forces acting on the crushed material in the one-roll crusher with the inclined surface of the jaw, the calculation of maximal possible value of the bend angle of the immovable jaw is performed.

  12. Erythropoietin promotes axonal regeneration after optic nerve crush in vivo by inhibition of RhoA/ROCK signaling pathway.

    Science.gov (United States)

    Tan, Haibo; Zhong, Yisheng; Shen, Xi; Cheng, Yu; Jiao, Qin; Deng, Lianfu

    2012-11-01

    We investigated whether the RhoA/ROCK pathway was involved in the effect of erythropoietin (EPO) to promote retinal ganglion cells (RGCs) axonal regeneration in a rat optic nerve crush (ONC) model. We demonstrated that both EPO and ROCK inhibitor Y-27632 significantly enhanced RGCs survival and axon regeneration in vivo, and the effects of these agents were additive. Expression of active-RhoA was decreased after EPO or Y-27632 per pull down assay and affinity precipitation. Administration of EPO and Y-27632 cocktail resulted in even more RhoA inactivation, decreased expression of ROCK-1 and ROCK-2, and increased expression of growth associated protein-43 (GAP-43) protein per immunohistochemistry and western blot analysis. Down-regulation of active-RhoA, ROCK-1, and ROCK-2 expression by EPO coincided with the appearance of larger numbers of regenerating axons. In conclusion, the RhoA/ROCK signaling pathway was involved in the EPO effect to promote RGCs axon regeneration after ONC.

  13. Internally Pressurized Spherical and Cylindrical Cavities in Rock Salt

    DEFF Research Database (Denmark)

    Krenk, Steen

    1978-01-01

    -linear zone and the volume reduction. Results are given for cavities in rock salt, and a comparison with measured stress concentrations is used to support the assumption of a hydrostatic stress state in undisturbed salt formations. Finally a method to estimate convergence due to creep is outlined....

  14. In-situ testing study on convection and temperature characteristics of a new crushed-rock slope embankment design in a permafrost region

    Institute of Scientific and Technical Information of China (English)

    MingHao Liu; FuJun Niu; JianHong Fang; ZhanJu Lin; Jing Luo; GuoAn Yin

    2014-01-01

    For-the-purpose-of-enhancing-air-convection-and-controlling-solar-radiation,-a-new-crushed-rock-slope-embankment-design-combined-with-a-sun-shade-measure-is-proposed.-A-newly-designed-embankment-was-constructed-in-the-Tuotuohe-section-of-the-Qinghai-Tibet-Railway-and-a-field-testing-experiment-was-carried-out-to-determine-its-convection-and-temperature-char-acteristics.-The-results-show-that-distinct-air-convection-occurred-in-the-crushed-rock-layer-of-the-new-embankment,-especially-in-cold-seasons,-which-was-enhanced-when-it-flowed-upwards-along-the-slope.-This-preliminarily-indicated-that-the-new-design-of-the-embankment-slope-was-good-for-reinforcing-air-convection-in-the-crushed-rock-layer.-The-frequent-fluctuations-of-the-convection-speed-and-the-environmental-wind-speed-were-in-good-agreement,-suggesting-that-the-convection-in-the-crushed-rock-primarily-came-from-the-ambient-wind.-It-was-also-preliminarily-determined-that-the-new-embankment-had-a-better-cooling-effect-and-sun-shade-effect-for-decreasing-the-temperature-of-the-embankment-slope-compared-with-a-traditional-crushed-rock-slope-embankment,-and-the-mean-temperature-difference-between-them-was-up-to-1.7-°C.-The-mean-annual-temperature-at-the-bottom-boundary-of-the-crushed-rock-layer-was-obviously-lower-than-that-at-the-top-boundary,-and-heat-flux-calculation-showed-that-the-shallow-soil-beneath-the-embankment-slope-was-weakly-releasing-heat,-all-of-which-indicated-that-the-new-embankment-slope-design-was-beneficial-to-the-thermal-stability-of-the-embankment.-This-study-is-helpful-in-providing-some-references-for-improved-engineering-design-and-maintenance-of-roadbeds-in-permafrost-regions.

  15. Geo-engineering evaluation of Termaber basalt rock mass for crushed stone aggregate and building stone from Central Ethiopia

    Science.gov (United States)

    Engidasew, Tesfaye Asresahagne; Barbieri, Giulio

    2014-11-01

    The geology of the central part of Ethiopia exhibits a variety of rock types that can potentially be developed for construction stone production, of which the most wide spread and important one is the Termaber basalt. Even though some preliminary work is done on these rocks towards construction material application, it remains largely that this resource is untouched and needs further scientific characterization for the use in large scale industrial application. Basaltic rocks have been widely used in many parts of the world as concrete aggregate and dimension stone for various civil structures. The present research study was carried out for Geo-engineering evaluation of Termaber basalt rock mass for crushed stone aggregate and building stone from Central Ethiopia (around Debre Birhan). The main objective of the present research study was to assess the general suitability of the Termaber basalt to be used as coarse aggregate for concrete mix and/or to utilize it as cut stone at industrial level. Only choice made with full knowledge of the basic characteristics of the material, of its performance and durability against the foreseen solicitations will ensure the necessary quality of the stone work and thereby a possibility to reach its intended service life. In order to meet out the objective of the present study, data from both field and laboratory were collected and analyzed. The field data included geological investigations based on different methods and sample collection while the laboratory work included, uniaxial compressive strength, ultrasonic pulse velocity, dynamic elasticity modulus, bulk density, water absorption, specific gravity, open porosity, aggregate impact value, petrographic examination and XRF, aggregate crushing value, Los Angeles abrasion value, sodium sulfate soundness, X-ray diffraction and alkali silica reactivity tests. The field and laboratory data were compiled and compared together to reveal the engineering performance of the rock mass in

  16. Microbial biodiversity in Alpine Permo-Triassic rock salt

    Science.gov (United States)

    Radax, C.; Wieland, H.; Pfaffenhuemer, M.; Leuko, S.; Rittmann, S.; Weidler, G.; Gruber, C.; Stan-Lotter, H.

    2003-04-01

    Alpine Permo-Triassic rock salt (age 200-250 million years) was shown several times to contain living extremely halophilic Archaea. These organisms might stem from ancient populations that became entrapped and persisted in the rock salt since then. For this reason, rock salt is considered a promising model system for the search for bacterial extraterrestrial life. In our studies on biodiversity in Alpine rock salt, we employed both culture-dependent and culture-independent, PCR-based methods. The latter approach indicated the presence of at least 12 distinct sequence types (phylotypes) in our samples, all of which belonged to the extremely halophilic Archaea. None of the recovered sequences was identical to sequences from databases, suggesting the avoidance of contaminants during experimental procedures. Two phylotypes could be assigned to taxonomically described members of this family; the remaining ten phylotypes appeared only remotely related to known genera of the extremely halophilic Archaea. In contrast, attempts to isolate organisms from the same sample on 15 different growth media so far yielded only two groups of isolates that could be differentiated based on their 16S rRNA genes. One group was very similar to Halococcus strains that we frequently isolated from Alpine rock salt; the other group was closely correlated to one of our novel phylotypes. Analyses of whole cell protein patterns allowed to further differentiate the latter group into two different subgroups that could not be distinguished at the molecular level. These results show that both culture-dependent and culture-independent strategies have to be applied in order to obtain a more complete view of microbial biodiversity in Permo-Triassic rock salt: culture-independent methods yield information on the gross microbial diversity in rock salt, whereas subtle differences can currently only be registered between cultivated strains.

  17. Magnetic coupling at perovskite and rock-salt structured interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Matvejeff, M., E-mail: mikko.matvejeff@picosun.com [Institute for Solid State Physics, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, 277-8581 Chiba (Japan); Department of Chemistry, Aalto University, Kemistintie 1, 02150 Espoo (Finland); Ahvenniemi, E. [Department of Chemistry, Aalto University, Kemistintie 1, 02150 Espoo (Finland); Takahashi, R.; Lippmaa, M. [Institute for Solid State Physics, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, 277-8581 Chiba (Japan)

    2015-10-05

    We study magnetic coupling between hole-doped manganite layers separated by either a perovskite or a rock-salt barrier of variable thickness. Both the type and the quality of the interface have a strong impact on the minimum critical barrier thickness where the manganite layers become magnetically decoupled. A rock-salt barrier layer only 1 unit cell (0.5 nm) thick remains insulating and is able to magnetically de-couple the electrode layers. The technique can therefore be used for developing high-performance planar oxide electronic devices such as magnetic tunnel junctions and quantum well structures that depend on magnetically and electronically sharp heterointerfaces.

  18. Study of TL response in heavily irradiated rock salt

    Energy Technology Data Exchange (ETDEWEB)

    Ortega, X.; Dies, X. (Univ. Politecnica de Catalunya, Barcelona (Spain). Inst. de Tecniques Energetiques); Cuevas, C. de las (Barcelona Univ. (Spain))

    1993-01-01

    Within the framework of the CEC R and D Programme ''Management and Storage of Radioactive Waste'', the study of the generation of radiation damage in heavily irradiated rock salt is being carried out. This work describes the experiments carried out for the validation of the TL techniques, in the assessment of the phenomena related to the energy absorbed by the rock salt, due to the high levels of irradiation. The samples analysed are natural rock salt coming from the Sallent mine (Spain). The chemical composition of the rocks is, in all cases, higher than 90% NaCl, having small amounts of SO[sub 4], Mg, K, Br and Sr as major impurities. A first set of irradiations was performed at the laboratory with a source of [sup 137]Cs. The doses reached were lower than 20Gy. A second set of irradiations was performed at an industrial facility with a source of [sup 60]Co, achieving doses up to 2.5 MGy. Afterwards the irradiated samples were analysed with TL and optical absorption techniques. The results have facilitated a study of the glow curves, their evolution in time and the influence of the chemical composition, the absorbed dose, and the absorbed dose rate. These experiments have increased knowledge of the behaviour of heavily irradiated rock salt. (Author).

  19. Specific Investigations Related to Salt Rock Behaviour

    DEFF Research Database (Denmark)

    Vons, L. H.; Zelikson, A.; Charo, L.

    1986-01-01

    In this paper results are given of work in various countries in rather unrelated areas of research. Nevertheless, since the studies have been undertaken to better understand salt behaviour, both from mechanical and chemical points of view, some connection between the studies can be found. Studies...

  20. Specific Investigations Related to Salt Rock Behaviour

    DEFF Research Database (Denmark)

    Vons, L. H.; Zelikson, A.; Charo, L.

    1986-01-01

    In this paper results are given of work in various countries in rather unrelated areas of research. Nevertheless, since the studies have been undertaken to better understand salt behaviour, both from mechanical and chemical points of view, some connection between the studies can be found. Studies...

  1. Physical Properties Data for Rock Salt

    Science.gov (United States)

    1981-01-01

    In certain other deposits, brines may probable extension of the Louann Salt of Jurassic age have originated as magmatic or artesian ground waters...1978). (1211 Clynne, M.A. and Potter, R.W., United States Geological (871 Reference (271, p. 108. Survey, Menlo Park , CA, unpublished data (1978...Properties of Park , Calif., 79 pp. (1965). [AD 625 568] Some Organic Liquids and of Fifteen of the Alkali Halides," [601 Laboratory for Insulation

  2. Behavior of Cs in Grimsel granodiorite. Sorption on main minerals and crushed rock

    Energy Technology Data Exchange (ETDEWEB)

    Muuri, Eveliina; Ikonen, Jussi; Matara-aho, Minja; Voutilainen, Mikko; Siitari-Kauppi, Marja [Helsinki Univ. (Finland). Dept. of Chemistry; Lindberg, Antero [Geological Survey of Finland, Espoo (Finland); Holgersson, Stellan [Chalmers University of Technology, Goeteborg (Sweden). Dept. of Chemical and Biological Engineering, Nuclear Chemistry; Martin, Andrew [Nagra (National Cooperative for the Disposal of Radioactive Waste), Wettingen (Switzerland)

    2016-11-01

    In this study the sorption of cesium was investigated on four different minerals; quartz, plagioclase, potassium feldspar and biotite as well as granodiorite obtained from the Grimsel test site in Switzerland. The experiments were conducted in the presence of the weakly saline Grimsel groundwater simulant by determining the distribution coefficients using batch sorption experiments and PHREEQC-modelling across a large concentration range. In addition, the purity of the minerals was measured by XRD and the specific surface areas by BET method using krypton. The distribution coefficients of cesium were largest on biotite (0.304±0.005 m{sup 3}/kg in 10{sup -8} M). Furthermore, the sorption of cesium on quartz was found to be negligibly small in all investigated concentrations and the sorption of cesium on potassium feldspar and plagioclase showed similar behavior against a concentration isotherm with distribution coefficients of 0.0368±0.0004 m{sup 3}/kg and 0.18±0.04 m{sup 3}/kg in 10{sup -8} M. Finally, cesium sorption behavior on crushed granodiorite followed the trend of one of its most abundant mineral, plagioclase with distribution coefficient values of 0.107±0.003 m{sup 3}/kg in 10{sup -8} M. At low concentrations (<1.0.10{sup -6} M) cesium was sorbed on the frayed edge sites of biotite and once these sites are fully occupied cesium sorbs additionally to the Type II and Planar sites. As a consequence, the sorption of cesium on biotite is decreased at concentrations >1.0.10{sup -6} M. Secondly cesium sorption on potassium feldspar and plagioclase showed similar non-linear behavior with varying concentration. The results were used to assist the interpretation of cesium diffusion process in the 2.5 year in-situ experiment carried out in the underground laboratory at Grimsel test site in Switzerland (2007-2009).

  3. The Characterization of the Crush Zones in the Dike of Ultramafic Rock and Associated Gabbro with a Help of Magnetic Survey

    Science.gov (United States)

    Kudo, S.; Iwamori, A.; Tanaka, Y.; Makino, M.; Okuma, S.; Miyakawa, A.; Nakatsuka, T.; Sasaki, T.; Yanagida, M.; Sugimori, T.; Kitao, H.; Asahi, N.; Shiomi, T.; Higashida, Y.

    2016-12-01

    The composite dike of the ultramafic rock and associated gabbro intruded in the shale and diabase in the upper of the Yakuno Ophiolite of the Paleozoic in the site of the Ohi nuclear power station of the KEPCO (the Kansai Electric Power Co., Inc.). The KEPCO has conducted several surveys such as tectonic landform interpretation, trench and drilling surveys, and crush zones in the dike were found by the trench survey. Detail observations with the X-ray CT images, thin sections and polished sections were conducted to study whether the crush zones were caused by fault activity or landslide along serpentinite metamorphosed from the ultramafic rock. The continuity of the crush zones was studied by an interpretation of the detail DEM and dense drillings which were conducted around the trench (25 drillings in about 25,000 square meters).As results of the study, we clarified that: The crush zones are classified into an inactive fault estimated to be sheared at the time of the intrusion of the dike and a slip surface of a shallow landslide. The fault is limited in the dike and does not extend into the shale or diabase. The shallow landslide resides along the distribution of the ultramafic rock remarkably metamorphosed to the serpentinite, which becomes unclear in deep underground. The distribution of the fault and landslide is enclosed in ultramafic rock of the dike which shows a high magnetic susceptibility. Therefore, a magnetic survey was conducted to clarify the distribution of the ultramafic rock within dozens of meters in depth. As the results of the survey, the areas of strong positive and negative magnetic anomalies corresponded to the distribution of the ultramafic rock confirmed by the trench and drilling surveys. The magnetic survey also revealed the shallow subsurface structures in such areas as shallow sea where the drilling was a few. The details about the magnetic survey and results of analyses are shown in Okuma et al. (2016, this meeting).

  4. Comprehensive approach to the assessment of nanosized fractions of polydisperse systems of crushed rocks

    Directory of Open Access Journals (Sweden)

    DANILOV Victor Evgenyevich

    2016-06-01

    Full Text Available The results of size determination for mechanically dispersed rock (polymineral sand, basalt based on methods of dynamic light scattering, gas (nitrogen sorption and electron microscopy were comparatively analyzed. The experimental samples are obtained by mechanical dispersion of raw materials on the planetary and colloidal grinding mills. There is a high correlation in the obtained experimental results. Method of dynamic light scattering makes it possible to analyze dimensional characteristics of polydispersed systems with high amount of nano- and submicron particles with sufficient sedimentation stability in the dispersion medium. Characteristics of particles size calculated by the specific surface area of the studied systems’ consider the content of the micro-size fraction. The effective diameter of the particles was proposed as the characteristics of their morphological structure. The calculation of the effective diameter is based on the particle mass.

  5. DSC modelling for predicting resilient modulus of crushed rock base as a road base material for Western Australia roads

    Institute of Scientific and Technical Information of China (English)

    KHOBKLANG Pakdee; VIMONSATIT Vanissorn; JITSANGIAM Peerapong; NIKRAZ Hamid

    2013-01-01

    In order to increase the applied efficiency of crushed rock base (CRB) in pavement structure design for Western Australia roads,the material modelling based on the experimental results was investigated,and the disturbed state concept (DSC) was used to predict the resilient modulus of CRB because of its simplicity and strong ability in capturing the elastic and inelastic responses of materials to loads.The actual deformation of DSC,at any loading state,was determined from its assumed relative intact (RI) state.The DSC equation of CRB was constructed by using a set of experimental results of resilient modulus tests,and an idealized material model,namely the linear elastic model,of relative intact (RI) part was considered.Analysis results reveal that the resilient modulus-applied stress relationships back-predicted by using the DSC modelling are consistent with the experimental results,so,the DSC equation is suited for predicting the resilient modulus of CRB specimen.However,the model and the equation coming from the test results are conducted in accordance with the Austroads standard,so further investigation and validation with respect to the field behaviours of pavement structure should be performed.7 figs,11 refs.

  6. Shielding factors of ions in rock-salt crystals

    Science.gov (United States)

    Michihiro, Y.; Mahan, G. D.

    1997-11-01

    The calculation of the quadrupole shielding factor of closed-shell ions in crystalline solids with rock-salt structure is done based on the self-consistent-field local-density approximation, modified Sternheimer equation, and spherical solid model. A significant reduction of the values of the quadrupole shielding factor is found for the anions, and the amount of the reduction is different in different crystals.

  7. Constitutive Modeling of the Thermomechanical Behavior of Rock Salt

    Science.gov (United States)

    Hampel, A.

    2016-12-01

    For the safe disposal of heat-generating high-level radioactive waste in rock salt formations, highly reliable numerical simulations of the thermomechanical and hydraulic behavior of the host rock have to be performed. Today, the huge progress in computer technology has enabled experts to calculate large and detailed computer models of underground repositories. However, the big ad­van­ces in computer technology are only beneficial when the applied material models and modeling procedures also meet very high demands. They result from the fact that the evaluation of the long-term integrity of the geological barrier requires an extra­polation of a highly nonlinear deforma­tion behavior to up to 1 million years, while the underlying experimental investigations in the laboratory or in situ have a duration of only days, weeks or at most some years. Several advanced constitutive models were developed and continuously improved to describe the dependences of various deformation phenomena in rock salt on in-situ relevant boundary conditions: transient and steady-state creep, evolution of damage and dilatancy in the DRZ, failure, post-failure behavior, residual strength, damage and dilatancy reduction, and healing. In a joint project series between 2004 and 2016, fundamental features of the advanced models were investigated and compared in detail with benchmark calculations. The study included procedures for the determination of characteristic salt-type-specific model parameter values and for the performance of numerical calculations of underground structures. Based on the results of this work and on specific laboratory investigations, the rock mechanical modeling is currently developed further in a common research project of experts from Germany and the United States. In this presentation, an overview about the work and results of the project series is given and the current joint research project WEIMOS is introduced.

  8. Technical support for GEIS: radioactive waste isolation in geologic formations. Volume 4. Baseline rock properties: salt

    Energy Technology Data Exchange (ETDEWEB)

    1978-04-01

    Salt has long been considered a possible repository medium for nuclear waste disposal. This report is a result of a literature survey to determine rock mass properties of a generic salt. The properties of bedded salt deposits from three different areas are considered, namely, the Salina basin, the Permia basin and the Paradox basin. Dome salts are also considered. Because of the special characteristics of salt, especially, its self-healing properties, the rock-mass properties are similar to the intact properties.

  9. Device for crushing rocks

    Energy Technology Data Exchange (ETDEWEB)

    Kanygin, A.S.; Bulavtsev, V.A.; Zhidkov, A.V.

    1984-01-01

    The purpose of the invention is to simplify the design. The device includes a hydrocylinder with main piston and rod, additional piston with rod placed in the cavity of the main piston rod, wedge attached to the additional piston rod, extension jaws attached to the hydrocylinder housing, and attachment for supply of the working fluid into the above-piston cavity of the rod in the main piston. The latter is made in the form of a channel with reverse valve which connects the rod cavity of the hydrocylinder to the above-piston cavity of the main piston rod. The reverse valve is in the main piston and is made with push rod which goes beyond the limits of the piston on the side of the hydrocylinder rod cavity. The device is designed to separate blocks from the massif on the borehole line.

  10. Mathematical Modelling for Micropiles Embedded in Salt Rock

    Directory of Open Access Journals (Sweden)

    Rădan (Toader Georgiana

    2016-03-01

    Full Text Available This study presents the results of the mathematical modelling for the micropiles foundation of an investement objective located in Slanic, Prahova county. Three computing models were created and analyzed with software, based on Finite Element Method. With Plaxis 2D model was analyzed the isolated micropile and the three-dimensional analysis was made with Plaxis 3D model, for group of micropiles. For the micropiles foundation was used Midas GTS-NX model. The mathematical models were calibrated based with the in-situ tests results for axially loaded micropiles, embedded in salt rock. The paper presents the results obtained with the three software, the calibration and validation models.

  11. Numerical model of halite precipitation in porous sedimentary rocks adjacent to salt diapirs

    Science.gov (United States)

    Li, Shiyuan; Wang, Yan; Zhao, Pengyun

    2017-10-01

    Salt diapirs are commonly seen in the North Sea. Below the Zechstein Group exist possibly overpressured salt-anhydrite formations. One explanation as to the salt precipitation in areas with salt diapirs is that salt cementation is thermally driven and occurs strongly in places adjacent to salt diapirs. This paper assumes that the sealing effect of the cap rock above the salt formations is compromised and overpressured fluids, carrying dissolved minerals such as anhydrite (CaSO4) and salt mineral components (NaCl of halite), flow into the porous sedimentary layers above the salt formations. Additionally, a salt-diapir-like structure is assumed to be at one side of the model. The numerical flow and heat transport simulator SHEMAT-Suite was developed and applied to calculating the concentrations of species, and dissolution and precipitation amounts. Results show that the overpressured salt-anhydrite formations have higher pressure heads and the species elements sodium and chlorite are transported into porous sediment rocks through water influx (saturated brine). Halite can precipitate as brine with sodium and chlorite ions flows to the cooler environment. Salt cementation of reservoir rocks leads to decreasing porosity and permeability near salt domes, and cementation of reservoir formations decreases with growing distance to the salt diapir. The proposed approach in this paper can also be used to evaluate precipitation relevant to scaling problems in geothermal engineering.

  12. Magnetic and mineralogical properties of salt rocks from the Zechstein of the Northern German Basin

    Science.gov (United States)

    Heinrich, Frances C.; Schmidt, Volkmar; Schramm, Michael; Mertineit, Michael

    2017-01-01

    Magnetic properties of rocks are often studied to characterize composition and fabric of rocks. For salt rocks, the basic relationships between their magnetic properties and composition, which are necessary to interpret rock magnetic data, are not yet established. Therefore, we studied different types of natural salt rock and pure salt minerals. We measured their magnetic properties (magnetic susceptibility, IRM acquisition curves, FORC diagrams, temperature-dependent magnetic susceptibility) and used analytical methods such as microscopy, XRD and ICP-OES to understand the relationship between magnetic properties and mineralogy. Salt rocks mainly consist of the diamagnetic minerals halite, carnallite, sylvine and anhydrite with negative magnetic susceptibilities. The magnetic susceptibilities of pure synthetic NaCl and KCl single crystals, show values of -14.5 × 10-6 SI and -13.5 × 10-6 SI, respectively. In contrast, in natural salt rocks higher magnetic susceptibility values were measured. The magnetic susceptibility of the samples investigated in this study shows a general increase from light rock salt (max. -10 × 10-6 SI) over carnallitite (max. 134 × 10-6 SI) to red sylvinite (max. 270 × 10-6 SI). Whole rock analyses suggests that increased magnetic susceptibility can be attributed to paramagnetic and ferromagnetic minerals that are contained within the insoluble residue. The magnetic susceptibility is mainly controlled by magnetite and phyllosilicates. Its measurement can therefore be used to detect subtle changes in the content of these minerals.

  13. The Thermal Damage Properties of Mudstone, Gypsum and Rock Salt from Yingcheng, Hubei, China

    Directory of Open Access Journals (Sweden)

    Jie Chen

    2015-03-01

    Full Text Available The impacts of temperature on the surface thermal damage of rock salt, gypsum and mudstone from the Yingcheng salt mine, China were investigated by the surface crack growth and propagation tests at different temperatures. We found that: (a high temperature could strengthen the rock salt molecular thermal motion and weaken the cohesion among the rock salt grains, so that the grain boundaries were more prone to slip and thus develop into cracks; (b high temperature could make the water molecules evaporate from rock specimens, which should change the physical properties of gypsum and mudstone; and (c high temperature had a significant effect on the interface between rock salt and gypsum and mudstone, therefore it should be easy to produce cracks with white or light yellow cumulate powder here. The surface crack growth and propagation of the rock salt, gypsum and mudstone have a positive correlation with the temperature by stereo microscope and the method of binary images, which could observe the surface thermal damage properties. Finally, the fractal dimension of the rock salt surface cracks was calculated based on fractal theory, and the evolution of the surface thermal damage was found from 50 to 260 °C.

  14. Evaluation of Five Sedimentary Rocks Other Than Salt for Geologic Repository Siting Purposes

    Energy Technology Data Exchange (ETDEWEB)

    Croff, A.G.; Lomenick, T.F.; Lowrie, R.S.; Stow, S.H.

    2003-11-15

    The US Department of Energy (DOE), in order to increase the diversity of rock types under consideration by the geologic disposal program, initiated the Sedimary ROck Program (SERP), whose immediate objectiv eis to evaluate five types of secimdnary rock - sandstone, chalk, carbonate rocks (limestone and dolostone), anhydrock, and shale - to determine the potential for siting a geologic repository. The evaluation of these five rock types, together with the ongoing salt studies, effectively results in the consideration of all types of relatively impermeable sedimentary rock for repository purposes. The results of this evaluation are expressed in terms of a ranking of the five rock types with respect to their potential to serve as a geologic repository host rock. This comparative evaluation was conducted on a non-site-specific basis, by use of generic information together with rock evaluation criteria (RECs) derived from the DOE siting guidelines for geologic repositories (CFR 1984). An information base relevant to rock evaluation using these RECs was developed in hydrology, geochemistry, rock characteristics (rock occurrences, thermal response, rock mechanics), natural resources, and rock dissolution. Evaluation against postclosure and preclosure RECs yielded a ranking of the five subject rocks with respect to their potential as repository host rocks. Shale was determined to be the most preferred of the five rock types, with sandstone a distant second, the carbonate rocks and anhydrock a more distant third, and chalk a relatively close fourth.

  15. Crush syndrome

    Directory of Open Access Journals (Sweden)

    Emily Lovallo

    2012-09-01

    Full Text Available The first detailed cases of crush syndrome were described in 1941 in London after victims trapped beneath bombed buildings presented with swollen limbs, hypovolemic shock, dark urine, renal failure, and ultimately perished. The majority of the data and studies on this topic still draw from large databases of earthquake victims. However, in Africa, a continent with little seismic activity, the majority of crush syndrome cases are instead victims of severe beatings rather than earthquake casualties, and clinical suspicion by emergency personnel must be high in this patient group presenting with oliguria or pigmenturia. Damaged skeletal muscle fibres and cell membranes lead to an inflammatory cascade resulting in fluid sequestration in the injured extremity, hypotension, hyperkalemia and hypocalcemia and their complications, and renal injury from multiple sources. Elevations in the serum creatinine, creatine kinase (CK, and potassium levels are frequent findings in these patients, and can help guide critical steps in management. Fluid resuscitation should begin prior to extrication of trapped victims or as early as possible, as this basic intervention has been shown to in large part prevent progression of renal injury to requiring haemodialysis. Alkalinization of the urine and use of mannitol for forced diuresis are recommended therapies under specific circumstances and are supported by studies done in animal models, but have not been shown to change clinical outcomes in human crush victims. In the past 70 years the crush syndrome and its management have been studied more thoroughly, however clinical practice guidelines continue to evolve.

  16. Granular Salt Summary: Reconsolidation Principles and Applications

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Frank; Popp, Till; Wieczorek, Klaus; Stuehrenberg, Dieter

    2014-07-01

    The purposes of this paper are to review the vast amount of knowledge concerning crushed salt reconsolidation and its attendant hydraulic properties (i.e., its capability for fluid or gas transport) and to provide a sufficient basis to understand reconsolidation and healing rates under repository conditions. Topics covered include: deformation mechanisms and hydro-mechanical interactions during reconsolidation; the experimental data base pertaining to crushed salt reconsolidation; transport properties of consolidating granulated salt and provides quantitative substantiation of its evolution to characteristics emulating undisturbed rock salt; and extension of microscopic and laboratory observations and data to the applicable field scale.

  17. Numerical Simulation on Open Wellbore Shrinkage and Casing Equivalent Stress in Bedded Salt Rock Stratum

    Directory of Open Access Journals (Sweden)

    Jianjun Liu

    2013-01-01

    Full Text Available Most salt rock has interbed of mudstone in China. Owing to the enormous difference of mechanical properties between the mudstone interbed and salt rock, the stress-strain and creep behaviors of salt rock are significantly influenced by neighboring mudstone interbed. In order to identify the rules of wellbore shrinkage and casings equivalent stress in bedded salt rock stratum, three-dimensional finite difference models were established. The effects of thickness and elasticity modulus of mudstone interbed on the open wellbore shrinkage and equivalent stress of casing after cementing operation were studied, respectively. The results indicate that the shrinkage of open wellbore and equivalent stress of casings decreases with the increase of mudstone interbed thickness. The increasing of elasticity modulus will reduce the shrinkage of open wellbore and casing equivalent stress. Research results can provide the scientific basis for the design of mud density and casing strength.

  18. Numerical simulation on open wellbore shrinkage and casing equivalent stress in bedded salt rock stratum.

    Science.gov (United States)

    Liu, Jianjun; Zhang, Linzhi; Zhao, Jinzhou

    2013-01-01

    Most salt rock has interbed of mudstone in China. Owing to the enormous difference of mechanical properties between the mudstone interbed and salt rock, the stress-strain and creep behaviors of salt rock are significantly influenced by neighboring mudstone interbed. In order to identify the rules of wellbore shrinkage and casings equivalent stress in bedded salt rock stratum, three-dimensional finite difference models were established. The effects of thickness and elasticity modulus of mudstone interbed on the open wellbore shrinkage and equivalent stress of casing after cementing operation were studied, respectively. The results indicate that the shrinkage of open wellbore and equivalent stress of casings decreases with the increase of mudstone interbed thickness. The increasing of elasticity modulus will reduce the shrinkage of open wellbore and casing equivalent stress. Research results can provide the scientific basis for the design of mud density and casing strength.

  19. Study on Mechanical Features of Brazilian Splitting Fatigue Tests of Salt Rock

    OpenAIRE

    Weichao Wang; Mengmeng Wang; Xiliang Liu

    2016-01-01

    The microtest, SEM, was carried out to study the fracture surface of salt rock after the Brazilian splitting test and splitting fatigue test were carried out with a servo-controlled test machine RMT-150B. The results indicate that the deviation of using the tablet splitting method is larger than that of using steel wire splitting method, in Brazilian splitting test of salt rock, when the conventional data processing method is adopted. There are similar deformation features in both the convent...

  20. Abundance of lanthanoids in rock salts determined by neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Honda, Teruyuki; Nozaki, Tetsuya [Musashi Inst. of Tech., Kawasaki, Kanagawa (Japan). Atomic Energy Research Lab.; Yui, Mitsuaki; Kikawada, Yoshikazu; Oi, Takao

    1998-06-01

    Contents of lanthanoids (Ln`s) of rock salts have been measured by the neutron activation analysis. Original salt samples were treated in advance of neutron irradiation so that Ln`s were enriched and amounts of interfering nuclides were reduced. The contents of Ln`s were at ppt-sub ppb levels and were comparable with or slightly lower than those of solar salts. The Ln abundance patterns of the salts were those with relative depletion in the heavy Ln`s, thus having negative slopes. It was indicated that, when salt deposit was formed, Ln`s were taken up by anhydrite more preferentially than by halite. (author)

  1. Influence of deformation on the fluid transport properties of salt rocks

    NARCIS (Netherlands)

    Peach, C.J.

    1991-01-01

    While the fluid transport properties of rocks are well understood under hydrostatic conditions, little is known regarding these properties in rocks undergoing crystal plastic deformation. However, such data are needed as input in the field of radioactive waste disposal in salt formations. They are a

  2. Influence of deformation on the fluid transport properties of salt rocks

    NARCIS (Netherlands)

    Peach, C.J.

    1991-01-01

    While the fluid transport properties of rocks are well understood under hydrostatic conditions, little is known regarding these properties in rocks undergoing crystal plastic deformation. However, such data are needed as input in the field of radioactive waste disposal in salt formations. They are a

  3. Geo Mechanical Analysis of Casing Failure in Bedded Rock Salt Formation

    Directory of Open Access Journals (Sweden)

    Tongtao Wang

    2012-08-01

    Full Text Available There are many bedded rock salt resources in China which are serviced as the hosts of underground natural gas storages. For the relatively thin nature of bedded rock salt and the local presence of other sedimentary rock formations, the design and safety evaluation of well completion casing take greater challenges to the engineers than that of casing in other type formations, i.e., limestone and carbonatite. The 2D and 3D geomechanical models of casing-cement sheath-rock salt are established in the paper based on the field data to obtain the creep loads in casing and find the main reasons causing casing failure. In addition, the effects of non-salt layer dip angle, friction factor between salt and non-salt layers and non-salt layer thickness, etc., on the stresses and deformations of casing are studied. The comprehensive results show hoop creep loads are the main reasons causing casing failure rather than radial creep loads. The cement sheath can improve the safety and optimize force state of casing even in perfect wellbore, which disagrees with Willson’s view that the cement sheath can be neglected in a salt formation wellbore with high quality. The non-uniform factor of radial creep loads in cement sheath is slightly smaller than that of original in-situ stresses, while that of radial creep loads in casing is greatly smaller than it. The stresses and deformations of casing increase with increasing thickness of non-salt layer and decrease with the increase of friction factor. When the non-salt layer dip angle is with a value of 50 deg, the stresses and deformations achieve the max and subsequently decrease.

  4. Rollerjaw Rock Crusher

    Science.gov (United States)

    Peters, Gregory; Brown, Kyle; Fuerstenau, Stephen

    2009-01-01

    The rollerjaw rock crusher melds the concepts of jaw crushing and roll crushing long employed in the mining and rock-crushing industries. Rollerjaw rock crushers have been proposed for inclusion in geological exploration missions on Mars, where they would be used to pulverize rock samples into powders in the tens of micrometer particle size range required for analysis by scientific instruments.

  5. Vacancy Structures and Melting Behavior in Rock-Salt GeSbTe

    Science.gov (United States)

    Zhang, Bin; Wang, Xue-Peng; Shen, Zhen-Ju; Li, Xian-Bin; Wang, Chuan-Shou; Chen, Yong-Jin; Li, Ji-Xue; Zhang, Jin-Xing; Zhang, Ze; Zhang, Sheng-Bai; Han, Xiao-Dong

    2016-05-01

    Ge-Sb-Te alloys have been widely used in optical/electrical memory storage. Because of the extremely fast crystalline-amorphous transition, they are also expected to play a vital role in next generation nonvolatile microelectronic memory devices. However, the distribution and structural properties of vacancies have been one of the key issues in determining the speed of melting (or amorphization), phase-stability, and heat-dissipation of rock-salt GeSbTe, which is crucial for its technological breakthrough in memory devices. Using spherical aberration-aberration corrected scanning transmission electron microscopy and atomic scale energy-dispersive X-ray mapping, we observe a new rock-salt structure with high-degree vacancy ordering (or layered-like ordering) at an elevated temperature, which is a result of phase transition from the rock-salt phase with randomly distributed vacancies. First-principles calculations reveal that the phase transition is an energetically favored process. Moreover, molecular dynamics studies suggest that the melting of the cubic rock-salt phases is initiated at the vacancies, which propagate to nearby regions. The observation of multi-rock-salt phases suggests another route for multi-level data storage using GeSbTe.

  6. The effects of naturally occurring impurities in rock salt

    Indian Academy of Sciences (India)

    Alina-Mihaela Badescu; Alexandra Saftoiu

    2014-09-01

    In this paper we investigate the effect that naturally occurring impurities in salt mines have both on effective permittivity of the medium and on radio wave propagation at ∼200 MHz. The effective permittivity is determined based on the dielectric properties of salt and the characteristics of the main impurities. We conclude that at such frequencies the scattering is negligible compared to absorptions. The effect of trapped water in different forms is also evaluated.

  7. Halophilic archaea cultivated from surface sterilized middle-late eocene rock salt are polyploid.

    Directory of Open Access Journals (Sweden)

    Salla T Jaakkola

    Full Text Available Live bacteria and archaea have been isolated from several rock salt deposits of up to hundreds of millions of years of age from all around the world. A key factor affecting their longevity is the ability to keep their genomic DNA intact, for which efficient repair mechanisms are needed. Polyploid microbes are known to have an increased resistance towards mutations and DNA damage, and it has been suggested that microbes from deeply buried rock salt would carry several copies of their genomes. Here, cultivable halophilic microbes were isolated from a surface sterilized middle-late Eocene (38-41 million years ago rock salt sample, drilled from the depth of 800 m at Yunying salt mine, China. Eight unique isolates were obtained, which represented two haloarchaeal genera, Halobacterium and Halolamina. We used real-time PCR to show that our isolates are polyploid, with genome copy numbers of 11-14 genomes per cell in exponential growth phase. The ploidy level was slightly downregulated in stationary growth phase, but the cells still had an average genome copy number of 6-8. The polyploidy of halophilic archaea living in ancient rock salt might be a factor explaining how these organisms are able to overcome the challenge of prolonged survival during their entombment.

  8. Radiation defects and energy storage in natural polycrystalline rock salt. Results of an in-situ test in the Permian rock salt of the Asse

    Energy Technology Data Exchange (ETDEWEB)

    Gies, H.; Rothfuchs, T. [Institut fuer Tieflagerung, Braunschweig (Germany); Celma, A.G.; Haas, J.B.M. de [Netherlands Energy Research Foundation, Petten (Netherlands); Pederson, L. [Pacific Northwest Lab., Richland, WA (United States)

    1994-12-31

    Radiation damage development and the corresponding energy storage in pure undeformed single crystals have frequently been studied in laboratory experiments, however little is known of irradiation experiments on natural rock salt (polycrystalline, deformed and impure) under geological conditions. The relevance of these parameters to the defect formation was revealed by a joint United States/Federal Republic of Germany in-situ test in the Asse Mine. Natural rock salt was heated and irradiated using Co-60 sources. Calculations of the amount of halite expected to be decomposed by radiolysis during the experiment were performed using the 1985 version of the Jain-Lidiard model. Qualitative agreement between theory and analyses was found for all the performed analyses. Quantitative and qualitative deviations of the natural samples behaviour from that of single undeformed crystals were observed and attributed to the influence of sulfatic admixtures, polycrystallinity and strain on radiation damage development and anneal. Special chemical methods, such as iodometric titration and uv-visible spectroscopy were applied in order to measure the hypochlorite ion, which forms in irradiated salt. Composite samples located closet to the Co-60 source averaged 0,4 micromoles neutral chlorine atoms per gram salt, a factor of two more than from other positions. Uv-vis analyses revealed more than a factor of ten greater neutral chlorine concentrations in coloured halite. Similarly, optical absorption measurements indicated a factor of ten difference in sodium metal colloid concentrations.

  9. Spanish participation in the Haw Project: Laboratory investigations on Gamma irradiation effects in rock salt

    Energy Technology Data Exchange (ETDEWEB)

    Cuevas, C. de las; Miralles, L.; Teixidor, P.; Garcia Veigas, J.; Dies, X.; Ortega, X.; Pueyo, J.J.

    1993-12-31

    In order to prove the safe disposal of high-level radioactive waste (HAW) in salt rock, a five years test disposal of thirty highly radioactive radiation sources is planned in the Asse salt mine, in the Federal Republic of Germany. The thirty radiation sources consist of steel canisters containing the vitrified radionuclides Caesium 137 and Strontium 90 in quantities sufficient to cover the bandwidth of heat generation and gamma radiation of real HAW. The radiation sources will be emplaced in six boreholes located in two galleries at the 800 m level. Two electrical heater tests were already started in November 1988 and are continuosly surveyed in respect of the rock mass. Also the handling system necessary for the emplacement of the radioactive canisters was developed and succesfully tested. A laboratory investigation programme on radiation effects in salt is being performed in advance to the radioactive canister emplacement. This programme includes the investigation of thermally and radiolytically induced water and gas release from the rock salt and the radiolytical decomposition of salt minerals. Part of this programme has been carried out since 1988 at the University of Barcelona, basically what refers to colloidal sodium determinations by light absorption measurements and microstructural studies on irradiated salt samples. For gamma dose and dose rate measurements in the test field, measuring systems consisting of ionisation chambers as well as solid state dosemeters were developed and tested. Thermomechanical computer code validation is performed by calculational predictions and parallel investigation of the stress and displacement fields in the underground test field.

  10. Dynamic subsidence prediction of ground surface above salt cavern gas storage considering the creep of rock salt

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A new model is proposed to predict the dynamic subsidence of ground surface above salt cavern gas storage during the leaching and storage, which takes into account the creep of rock salt. In the model, the extended form of Gaussian curve is adopted to figure out the shape of subsidence areas. The corresponding theoretical formulas are derived. In addition, parameters are studied to investigate the surface subsidence as a function of the salt ejection rate, internal pressure, buried depth, diameter, height, running time, etc. Through an example, the subsidence of the salt cavern gas storage located at Jiangsu of China obtained by the new model was compared with those by Peter A F formula, Schober & Sroka formula and FLAC3D through simulation. The results showed the proposed model is precise and correct, and can meet the actual engineering demands. The surface subsidence is equidirectional with the increase of salt ejection rate, depth, diameter, height, and running time, but reverse to the increase of internal pressure. The depth, diameter, running time and internal pressure have great effects on the subsidence, whereas the salt ejection rate and height have little influences on it.

  11. Geohydromechanical Processes in the Excavation Damaged Zone in Crystalline Rock, Rock Salt, and Indurated and Plastic Clays

    Energy Technology Data Exchange (ETDEWEB)

    Tsang, Chin-Fu; Bernier, Frederic; Davies, Christophe

    2004-06-20

    The creation of an excavation disturbed zone or excavation damaged zone is expected around all man-made openings in geologic formations. Macro- and micro-fracturing, and in general a redistribution of in situ stresses and rearrangement of rock structures, will occur in this zone, resulting in drastic changes of permeability to flow, mainly through the fractures and cracks induced by excavation. Such an EDZ may have significant implications for the operation and long-term performance of an underground nuclear waste repository. Various issues of concern need to be evaluated, such as processes creating fractures in the excavation damaged zone, the degree of permeability increase, and the potential for sealing or healing (with permeability reduction) in the zone. In recent years, efforts along these lines have been made for a potential repository in four rock types-crystalline rock, salt, indurated clay, and plastic clay-and these efforts have involved field, laboratory, and theoretical studies. The present work involves a synthesis of the ideas and issues that emerged from presentations and discussions on EDZ in these four rock types at a CLUSTER Conference and Workshop held in Luxembourg in November, 2003. First, definitions of excavation disturbed and excavation damaged zones are proposed. Then, an approach is suggested for the synthesis and intercomparison of geohydromechanical processes in the EDZ for the four rock types (crystalline rock, salt, indurated clay, and plastic clay). Comparison tables of relevant processes, associated factors, and modeling and testing techniques are developed. A discussion of the general state-of-the-art and outstanding issues are also presented. A substantial bibliography of relevant papers on the subject is supplied at the end of the paper.

  12. Probabilistic Analysis of a Rock Salt Cavern with Application to Energy Storage Systems

    Science.gov (United States)

    Mahmoudi, Elham; Khaledi, Kavan; Miro, Shorash; König, Diethard; Schanz, Tom

    2017-01-01

    This study focuses on the failure probability of storing renewable energy in the form of hydrogen or compressed air in rock salt caverns. The validation of the short- and long-term integrity and stability of rock salt cavern is a prerequisite in their design process. The present paper provides a reliability-based analysis of a typical renewable energy storage cavern in rock salt. An elasto-viscoplastic creep constitutive model is implemented into a numerical model of rock salt cavern to assess its behavior under different operation conditions. Sensitivity measures of different variables involved in the mechanical response of cavern are computed by elementary effect global sensitivity method. Subset simulation methodology is conducted to measure the failure probability of the system with a low computational cost. This methodology is further validated by a comparison with a Monte Carlo-based probabilistic analysis. The propagation of parameter uncertainties and the failure probability against different failure criteria are evaluated by utilizing a Monte Carlo-based analysis. In this stage, the original finite element model is substituted by a surrogate model to further reduce the computational effort. Finally, a reliability analysis approach is employed to obtain the minimum admissible internal pressure in a cavern.

  13. Study on Mechanical Features of Brazilian Splitting Fatigue Tests of Salt Rock

    Directory of Open Access Journals (Sweden)

    Weichao Wang

    2016-01-01

    Full Text Available The microtest, SEM, was carried out to study the fracture surface of salt rock after the Brazilian splitting test and splitting fatigue test were carried out with a servo-controlled test machine RMT-150B. The results indicate that the deviation of using the tablet splitting method is larger than that of using steel wire splitting method, in Brazilian splitting test of salt rock, when the conventional data processing method is adopted. There are similar deformation features in both the conventional splitting tests and uniaxial compression tests. The stress-strain curves include compaction, elasticity, yielding, and failure stage. Both the vertical deformation and horizontal deformation of splitting fatigue tests under constant average loading can be divided into three stages of “loosening-tightness-loosening.” The failure modes of splitting fatigue tests under the variational average loading are not controlled by the fracturing process curve of the conventional splitting tests. The deformation extent of fatigue tests under variational average loading is even greater than that of conventional splitting test. The tensile strength of salt rock has a relationship with crystallization conditions. Tensile strength of thick crystal salt rock is lower than the bonded strength of fine-grain crystals.

  14. New scenario for the accumulation and release of radiation damage in rock salt and related materials

    NARCIS (Netherlands)

    Hartog, H.W. den; Vainshtein, D.I.; Dubinko, V.I.; Turkin, A.A.

    2002-01-01

    Rock salt might be a promising geological medium for a radioactive waste repository. However, we have observed that even a basically stable compound such as NaCl may become unstable after heavy irradiation. As a result of the irradiation, dislocations, Na and Cl2 precipitates and large voids are pro

  15. Impact of rock salt creep law choice on subsidence calculations for hydrocarbon reservoirs overlain by evaporite caprocks

    Science.gov (United States)

    Marketos, G.; Spiers, C. J.; Govers, R.

    2016-06-01

    Accurate forward modeling of surface subsidence above producing hydrocarbons reservoirs requires an understanding of the mechanisms determining how ground deformation and subsidence evolve. Here we focus entirely on rock salt, which overlies a large number of reservoirs worldwide, and specifically on the role of creep of rock salt caprocks in response to production-induced differential stresses. We start by discussing available rock salt creep flow laws. We then present the subsidence evolution above an axisymmetric finite element representation of a generic reservoir that extends over a few kilometers and explore the effects of rock salt flow law choice on the subsidence response. We find that if rock salt creep is linear, as appropriate for steady state flow by pressure solution, the subsidence response to any pressure reduction history contains two distinct components, one that leads to the subsidence bowl becoming narrower and deeper and one that leads to subsidence rebound and becomes dominant at later stages. This subsidence rebound becomes inhibited if rock salt deforms purely through steady state power law creep at low stresses. We also show that an approximate representation of transient creep leads to relatively small differences in subsidence predictions. Most importantly, the results confirm that rock salt flow must be modeled accurately if good subsidence predictions are required. However, in practice, large uncertainties exist in the creep behavior of rock salt, especially at low stresses. These are a consequence of the spatial variability of rock salt physical properties, which is practically impossible to constrain. A conclusion therefore is that modelers can only resort to calculating bounds for the subsidence evolution above producing rock salt-capped reservoirs.

  16. A fractional derivative approach to full creep regions in salt rock

    DEFF Research Database (Denmark)

    Zhou, H. W.; Wang, C. P.; Mishnaevsky, Leon

    2013-01-01

    Based on the definition of the constant-viscosity Abel dashpot, a new creep element, referred to as the variable-viscosity Abel dashpot, is proposed to characterize damage growth in salt rock samples during creep tests. Ultrasonic testing is employed to determine a formula of the variable viscosity...... coefficient, indicating that the change of the variable viscosity coefficient with the time meets a negative exponent law. In addition, by replacing the Newtonian dashpot in the classical Nishihara model with the variable-viscosity Abel dashpot, a damage-mechanism-based creep constitutive model is proposed...... rock. Furthermore, a sensitivity study is carried out, showing the effects of stress level, fractional derivative order and viscosity coefficient exponent on creep strain of salt rock. It is indicated that the fractional derivative creep model proposed in the paper provides a precise description...

  17. Investigating the sealing capacity of a seal system in rock salt (DOPAS project)

    Energy Technology Data Exchange (ETDEWEB)

    Jantschik, Kyra; Moog, Helge C.; Czaikowski, Oliver; Wieczorek, Klaus [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) gGmbH, Braunschweig (Germany)

    2016-11-15

    This paper describes research and development work on plugging and sealing repositories, an issue of fundamental importance for the rock salt option which represents one of the three European repository options, besides the clay rock and the crystalline rock options. The programme aims at providing experimental data needed for the theoretical analysis of the long-term sealing capacity of concrete- based sealing materials. In order to demonstrate hydro-mechanical material stability under representative load scenarios, a comprehensive laboratory testing programme is carried out. This comprises investigation of the sealing capacity of the combined seal system and impact of the so-called excavation-damaged zones (EDZ) as well as investigation of the hydro-chemical long-term stability of the seal in contact with different brines under diffusive and advective conditions. This paper presents experimental approaches and preliminary results from laboratory investigations on salt concrete and combined systems as obtained to date.

  18. Uniaxial creep as a control on mercury intrusion capillary pressure in consolidating rock salt

    Energy Technology Data Exchange (ETDEWEB)

    Dewers, Thomas [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Heath, Jason E. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Leigh, Christi D. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

    2015-09-01

    The nature of geologic disposal of nuclear waste in salt formations requires validated and verified two - phase flow models of transport of brine and gas through intact, damaged, and consolidating crushed salt. Such models exist in oth er realms of subsurface engineering for other lithologic classes (oil and gas, carbon sequestration etc. for clastics and carbonates) but have never been experimentally validated and parameterized for salt repository scenarios or performance assessment. Mo dels for waste release scenarios in salt back - fill require phenomenological expressions for capillary pressure and relative permeability that are expected to change with degree of consolidation, and require experimental measurement to parameterize and vali date. This report describes a preliminary assessment of the influence of consolidation (i.e. volume strain or porosity) on capillary entry pressure in two phase systems using mercury injection capillary pressure (MICP). This is to both determine the potent ial usefulness of the mercury intrusion porosimetry method, but also to enable a better experimental design for these tests. Salt consolidation experiments are performed using novel titanium oedometers, or uniaxial compression cells often used in soil mech anics, using sieved run - of - mine salt from the Waste Isolation Pilot Plant (WIPP) as starting material. Twelve tests are performed with various starting amounts of brine pore saturation, with axial stresses up to 6.2 MPa (%7E900 psi) and temperatures to 90 o C. This corresponds to UFD Work Package 15SN08180211 milestone "FY:15 Transport Properties of Run - of - Mine Salt Backfill - Unconsolidated to Consolidated". Samples exposed to uniaxial compression undergo time - dependent consolidation, or creep, to various deg rees. Creep volume strain - time relations obey simple log - time behavior through the range of porosities (%7E50 to 2% as measured); creep strain rate increases with temperature and applied stress as

  19. Mineralogical and microstructural investigations of fractures in Permian z2 potash seam and surrounding salt rocks

    Science.gov (United States)

    Mertineit, Michael; Grewe, Wiebke; Schramm, Michael; Hammer, Jörg; Blanke, Hartmut; Patzschke, Mario

    2017-04-01

    Fractures occur locally in the z2 potash seam (Kaliflöz Staßfurt). Most of them extend several centimeter to meter into the surrounding salt rocks. The fractures are distributed on all levels in an extremely deformed area of the Morsleben salt mine, Northern Germany. The sampling site is located within a NW-SE trending synclinal structure, which was reverse folded (Behlau & Mingerzahn 2001). The samples were taken between the -195 m and - 305 m level at the field of Marie shaft. In this area, more than 200 healed fractures were mapped. Most of them show opening widths of only a few millimeters to rarely 10 cm. The fractures in rock salt are filled with basically polyhalite, halite and carnallite. In the potash seam, the fractures are filled with kainite, halite and minor amounts of carnallite and polyhalite. In some cases the fracture infill changes depending on the type of surrounding rocks. There are two dominant orientations of the fractures, which can be interpreted as a conjugated system. The main orientation is NE-SW trending, the dip angles are steep (ca. 70°, dip direction NW and SE, respectively). Subsequent deformation of the filled fractures is documented by a strong grain shape fabric of kainite, undulatory extinction and subgrain formation in kainite, and several mineral transformations. Subgrain formation in halite occurred in both, the fracture infill and the surrounding salt rocks. The results correlate in parts with investigations which were carried out at the close-by rock salt mine Braunschweig-Lüneburg (Horn et al. 2016). The development of the fractures occurred during compression of clayey salt rocks. However, the results are only partly comparable due to different properties (composition, impurities) of the investigated stratigraphic units. Further investigations will focus on detailed microstructural and geochemical analyses of the fracture infill and surrounding salt rocks. Age dating of suitable minerals, e.g. polyhalite (Leitner et al

  20. Preliminary state-of-the-art survey: mining techniques for salt and other rock types

    Energy Technology Data Exchange (ETDEWEB)

    1976-12-01

    This is a systematic review of the state-of-the-art of underground mining and excavation technology in the U.S. as applied to salt, limestone, shale, and granite. Chapter 2 covers the basic characteristics of these rock types, the most frequently used underground mining methods, shaft and slope entry construction, equipment, and safety and productivity data. Chapters 3 and 4 summarize underground salt and limestone mining in the U.S. Chapter 5 shows that large amounts of thick shale exist in the U.S., but little is mined. Chapter 6 discusses underground excavations into granite-type rocks. Suggestions are given in the last chapter for further study. (DLC)

  1. Measurements of the Suitability of Large Rock Salt Formations for Radio Detection of High Energy Neutrinos

    CERN Document Server

    Gorham, P W; Odian, A; Williams, D; Besson, D; Frichter, G; Tantawi, S G; Gorham, Peter; Saltzberg, David; Odian, Allen; Williams, Dawn; Besson, David; Frichter, George; Tantawi, Sami

    2002-01-01

    We have investigated the possibility that large rock salt formations might be suitable as target masses for detection of neutrinos of energies about 10 PeV and above. In neutrino interactions at these energies, the secondary electromagnetic cascade produces a coherent radio pulse well above ambient thermal noise via the Askaryan effect. We describe measurements of radio-frequency attenuation lengths and ambient thermal noise in two salt formations. Measurements in the Waste Isolation Pilot Plant (WIPP), located in an evaporite salt bed in Carlsbad, NM yielded short attenuation lengths, 3-7 m over 150-300 MHz. However, measurements at United Salt's Hockley mine, located in a salt dome near Houston, Texas yielded attenuation lengths in excess of 250 m at similar frequencies. We have also analyzed early ground-penetrating radar data at Hockley mine and have found additional evidence for attenuation lengths in excess of several hundred meters at 440 MHz. We conclude that salt domes, which may individually contain...

  2. Mechanical behavior of New Mexico rock salt in triaxial compression up to 200/sup 0/C

    Energy Technology Data Exchange (ETDEWEB)

    Wawersik, W. R.; Hannum, D. W.

    1978-01-01

    An extensive experimental program is being conducted to determine the mechanical behavior of New Mexico rock salt in support of the structural design of a Radioactive Waste Isolation Pilot Plant (WIPP). In this initial report, three groups of tests are discussed to identify the relative and site-specific importance of deviator stress, confining pressure (mean stress), temperature, time (loading rate), and stress path. The three groups of experiments consist of (1) hydrostatic loading, (2) conventional triaxial compression tests (sigma/sub 1/ > sigma/sub 2/ = sigma/sub 3/ = const.), and (3) variable stress path tests including experiments at approximately constant sigma/sub 1/ and at constant mean stress. All data were generated on 100 mm diameter specimens. The rock salt exhibited nonlinear response under all loading conditions, practically zero initial elastic limit and an apparent inseparability of permanent deformations into time-independent and time-dependent components. Pressure and temperature did not alter the elastic constants but affected the principal strain ratio, the ratio volumetric strain/shear strain, rock salt ductility, and the ultimate stress. In particular, low pressure and temperature permitted pronounced dilatancy and loss in load bearing ability. Under such conditions the volumetric strains reach sizable fractions of the shear strains. Pressure remained important even at high temperature because it influenced the rate of shearing. Load path and stress history may be significant under deviatoric loading conditions and for large variations in pressure.

  3. Effect of Dihedral Angle and Porosity on Percolating-Sealing Capacity of Texturally Equilibrated Rock Salt

    Science.gov (United States)

    Ghanbarzadeh, S.; Hesse, M. A.; Prodanovic, M.; Gardner, J. E.

    2013-12-01

    Salt deposits in sedimentary basins have long been considered to be a seal against fluid penetration. However, experimental, theoretical and field evidence suggests brine (and oil) can wet salt crystal surfaces at higher pressures and temperatures, which can form a percolating network. This network may act as flow conduits even at low porosities. The aim of this work is to investigate the effects of dihedral angle and porosity on the formation of percolating paths in different salt network lattices. However, previous studies considered only simple homogeneous and isotropic geometries. This work extends the analysis to realistic salt textures by presenting a novel numerical method to describe the texturally equilibrated pore shapes in polycrystalline rock salt and brine systems. First, a theoretical interfacial topology was formulated to minimize the interfacial surface between brine and salt. Then, the resulting nonlinear system of ordinary differential equations was solved using the Newton-Raphson method. Results show that the formation of connected fluid channels is more probable in lower dihedral angles and at higher porosities. The connectivity of the pore network is hysteretic, because the connection and disconnection at the pore throats for processes with increasing or decreasing porosities occur at different porosities. In porous media with anisotropic solids, pores initially connect in the direction of the shorter crystal axis and only at much higher porosities in the other directions. Consequently, even an infinitesimal elongation of the crystal shape can give rise to very strong anisotropy in permeability of the pore network. Also, fluid flow was simulated in the resulting pore network to calculate permeability, capillary entry pressure and velocity field. This work enabled us to investigate the opening of pore space and sealing capacity of rock salts. The obtained pore geometries determine a wide range of petrophysical properties such as permeability and

  4. Impact of rock salt creep law choice on subsidence calculations for hydrocarbon reservoirs overlain by evaporite caprocks

    NARCIS (Netherlands)

    Marketos, G.; Spiers, C.J.; Govers, R.

    2016-01-01

    Accurate forward modeling of surface subsidence above producing hydrocarbons reservoirs requires an understanding of the mechanisms determining how ground deformation and subsidence evolve. Here we focus entirely on rock salt, which overlies a large number of reservoirs worldwide, and specifically

  5. Heart transaminase in the rock crab, Cancer irroratus, exposed to cadmium salts

    Energy Technology Data Exchange (ETDEWEB)

    Gould, E.; Collier, R.S.; Karolus, J.J.; Givens, S.

    1976-01-01

    When rock crabs, Cancer irroratus, were exposed for 4 days to 1 ppM cadmium as the chloride salt, aspartate aminotransferase activity in heart muscle preparations increased significantly over heart AAT in the control crabs. When crabs were exposed to 1 ppM cadmium as the nitrate salt in analogous experiments, however, the heart AAT was slightly depressed, but not to a significant degree. That the nitrate salt of cadmium did not produce the same effect as the chloride salt underscores the importance of the form in which a metal occurs in the environment. Metal ions bind to various ligands, metabolic and otherwise, to an extent largely dependent upon the nature of their immediate chemical association. The results reported here clearly indicate that cadmium is more toxic as the chloride salt than as the nitrate. Data indicate that some enzymes in metal exposed animals may develop a degree of tolerance to higher-than-normal concentrations of cations, a tolerance that may lessen the necessary sensitivity to biochemical modulators, such as magnesium.

  6. Deformation and transport processes in salt rocks : An experimental study exploring effects of pressure and stress relaxation

    NARCIS (Netherlands)

    Muhammad, Nawaz

    2015-01-01

    The presence of evaporitic formations in sedimentary basins, often dominated by the salt mineral halite, is of great influence on the structural style developed during tectonic events. On a somewhat smaller scale, salt rocks often host a variety of deep solution mined caverns, which are increasingly

  7. Accelerator Measurments of the Askaryan Effect in Rock Salt: A Roadmap Toward Teraton Underground Neutrino Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Gorham, P.

    2004-12-15

    We report on further SLAC measurements of the Askaryan effect: coherent radio emission from charge asymmetry in electromagnetic cascades. We used synthetic rock salt as the dielectric medium, with cascades produced by GeV bremsstrahlung photons at the Final Focus Test Beam. We extend our prior discovery measurements to a wider range of parameter space and explore the effect in a dielectric medium of great potential interest to large scale ultra-high energy neutrino detectors: rock salt (halite), which occurs naturally in high purity formations containing in many cases hundreds of cubic km of water-equivalent mass. We observed strong coherent pulsed radio emission over a frequency band from 0.2-15 GHz. A grid of embedded dual-polarization antennas was used to confirm the high degree of linear polarization and track the change of direction of the electric-field vector with azimuth around the shower. Coherence was observed over 4 orders of magnitude of shower energy. The frequency dependence of the radiation was tested over two orders of magnitude of UHF and microwave frequencies. We have also made the first observations of coherent transition radiation from the Askaryan charge excess, and the result agrees well with theoretical predictions. Based on these results we have performed detailed and conservative simulation of a realistic GZK neutrino telescope array within a salt-dome, and we find it capable of detecting 10 or more contained events per year from even the most conservative GZK neutrino models.

  8. Steady-State Creep of Rock Salt: Improved Approaches for Lab Determination and Modelling

    Science.gov (United States)

    Günther, R.-M.; Salzer, K.; Popp, T.; Lüdeling, C.

    2015-11-01

    Actual problems in geotechnical design, e.g., of underground openings for radioactive waste repositories or high-pressure gas storages, require sophisticated constitutive models and consistent parameters for rock salt that facilitate reliable prognosis of stress-dependent deformation and associated damage. Predictions have to comprise the active mining phase with open excavations as well as the long-term development of the backfilled mine or repository. While convergence-induced damage occurs mostly in the vicinity of openings, the long-term behaviour of the backfilled system is dominated by the damage-free steady-state creep. However, because in experiments the time necessary to reach truly stationary creep rates can range from few days to years, depending mainly on temperature and stress, an innovative but simple creep testing approach is suggested to obtain more reliable results: A series of multi-step tests with loading and unloading cycles allows a more reliable estimate of stationary creep rate in a reasonable time. For modelling, we use the advanced strain-hardening approach of Günther-Salzer, which comprehensively describes all relevant deformation properties of rock salt such as creep and damage-induced rock failure within the scope of an unified creep ansatz. The capability of the combination of improved creep testing procedures and accompanied modelling is demonstrated by recalculating multi-step creep tests at different loading and temperature conditions. Thus reliable extrapolations relevant to in-situ creep rates (10^{-9} to 10^{-13} s^{-1}) become possible.

  9. Bonding preference of carbon, nitrogen, and oxygen in niobium-based rock-salt structures.

    Science.gov (United States)

    Miura, Akira; Takei, Takahiro; Kumada, Nobuhiro; Wada, Satoshi; Magome, Eisuke; Moriyoshi, Chikako; Kuroiwa, Yoshihiro

    2013-09-03

    Carbon, nitrogen, and oxygen are essential components in solid-state materials. However, understanding their preference on the bonding to metals has not been straightforward. Here, niobium carbide, nitride, and oxide with simple rock-salt-based structures were analyzed by first-principles calculations and synchrotron X-ray diffraction. We found that an increase in the atomic number from carbon to oxygen formed fewer and shorter bonds to metals with better hybridization of atomic orbitals. This can provide a simple guiding principle for understanding the bonding and designing carbides, nitrides, oxides, and mixed-anion compounds.

  10. Vacancy Structures and Melting Behavior in Rock-Salt GeSbTe

    OpenAIRE

    Bin Zhang; Xue-Peng Wang; Zhen-Ju Shen; Xian-Bin Li; Chuan-Shou Wang; Yong-Jin Chen; Ji-Xue Li; Jin-Xing Zhang; Ze Zhang; Sheng-Bai Zhang; Xiao-Dong Han

    2016-01-01

    Ge-Sb-Te alloys have been widely used in optical/electrical memory storage. Because of the extremely fast crystalline-amorphous transition, they are also expected to play a vital role in next generation nonvolatile microelectronic memory devices. However, the distribution and structural properties of vacancies have been one of the key issues in determining the speed of melting (or amorphization), phase-stability, and heat-dissipation of rock-salt GeSbTe, which is crucial for its technological...

  11. Forensic Analysis of the May 2014 West Salt Creek Rock Avalanche in Western Colorado

    Science.gov (United States)

    Coe, J. A.; Baum, R. L.; Allstadt, K.; Kochevar, B. F.; Schmitt, R. G.; Morgan, M. L.; White, J. L.; Stratton, B. T.; Hayashi, T. A.; Kean, J. W.

    2015-12-01

    The rain-on-snow induced West Salt Creek rock avalanche occurred on May 25, 2014 on the northern flank of Grand Mesa. The avalanche was rare for the contiguous U.S. because of its large size (59 M m3) and high mobility (Length/Height=7.2). To understand the avalanche failure sequence, mechanisms, and mobility, we conducted a forensic analysis using large-scale (1:1000) structural mapping and seismic data. We used high-resolution, Unmanned Aircraft System (UAS) imagery as a base for our field mapping and analyzed seismic data from 22 broadband stations (distances avalanche exerted on the earth and tracked these forces using curves in the avalanche path. Our results revealed that the rock avalanche was a cascade of landslide events, rather than a single massive failure. The sequence began with a landslide/debris flow that started about 10 hours before the main avalanche. The main avalanche lasted just over 3 minutes and traveled at average velocities ranging from 15 to 36 m/s. For at least two hours after the avalanche ceased movement, a central, hummock-rich, strike-slip bound core continued to move slowly. Following movement of the core, numerous shallow landslides, rock slides, and rock falls created new structures and modified topography. Mobility of the main avalanche and central core were likely enhanced by valley floor material that liquefied from undrained loading by the overriding avalanche. Although the base was likely at least partially liquefied, our mapping indicates that the overriding avalanche internally deformed predominantly by sliding along discrete shear surfaces in material that was nearly dry and had substantial frictional strength. These results indicate that the West Salt Creek avalanche, and probably other long-traveled avalanches, could be modeled as two layers: a liquefied basal layer; and a thicker and stronger overriding layer.

  12. Radioactive waste isolation in salt: geochemistry of brine in rock salt in temperature gradients and gamma-radiation fields - a selective annotated bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Hull, A.B.; Williams, L.B.

    1985-07-01

    Evaluation of the extensive research concerning brine geochemistry and transport is critically important to successful exploitation of a salt formation for isolating high-level radioactive waste. This annotated bibliography has been compiled from documents considered to provide classic background material on the interactions between brine and rock salt, as well as the most important results from more recent research. Each summary elucidates the information or data most pertinent to situations encountered in siting, constructing, and operating a mined repository in salt for high-level radioactive waste. The research topics covered include the basic geology, depositional environment, mineralogy, and structure of evaporite and domal salts, as well as fluid inclusions, brine chemistry, thermal and gamma-radiation effects, radionuclide migration, and thermodynamic properties of salts and brines. 4 figs., 6 tabs.

  13. Accelerator Measurements of the Askaryan effect in Rock Salt: A Roadmap Toward Teraton Underground Neutrino Detectors

    CERN Document Server

    Gorham, P W; Field, R C; Guillian, E; Milincic, R; Walz, D; Williams, D

    2004-01-01

    We report on further SLAC measurements of the Askaryan effect: coherent radio emission from charge asymmetry in electromagnetic cascades. We used synthetic rock salt as the dielectric medium, with cascades produced by GeV bremsstrahlung photons at the Final Focus Test Beam. We extend our prior discovery measurements to a wider range of parameter space and explore the effect in a dielectric medium of great potential interest to large scale ultra-high energy neutrino detectors: rock salt (halite), which occurs naturally in high purity formations containing in many cases hundreds of cubic km of water-equivalent mass. We observed strong coherent pulsed radio emission over a frequency band from 0.2-15 GHz. A grid of embedded dual-polarization antennas was used to confirm the high degree of linear polarization and track the change of direction of the electric-field vector with azimuth around the shower. Coherence was observed over 4 orders of magnitude of shower energy. The frequency dependence of the radiation was...

  14. Measurements of Coherent Cherenkov Radiation in Rock Salt: Implications for GZK Neutrino Underground Detector

    CERN Document Server

    Milincic, R; Saltzberg, D; Field, R C; Guillian, G; Walz, D; Williams, D

    2005-01-01

    We report on further SLAC measurements of the Askaryan effect: coherent radio emission from charge asymmetry in electromagnetic cascades. We used synthetic rock salt as the dielectric medium, with cascades produced by GeV bremsstrahlung photons at the Final Focus Test Beam. We extend our prior discovery measurements to a wider range of parameter space and explore the effect in a dielectric medium of great potential interest to large scale ultra-high energy neutrino detectors: rock salt. We observed strong coherent pulsed radio emission over a frequency band from 0.2-15 GHz. A grid of embedded dual-polarization antennas was used to confirm the linear polarization and track the change of direction of the electric-field vector around the shower. Coherence was observed over 4 orders of magnitude of shower energy. The frequency dependence of the radiation was tested over two orders of magnitude of UHF and microwave frequencies. Based on these results we have performed a simulation of a realistic GZK neutrino teles...

  15. Microstructures in naturally deformed Upper Rotliegend salt rocks from Northern Germany

    Science.gov (United States)

    Henneberg, Mareike; Hammer, Jörg; Mertineit, Michael

    2017-04-01

    Permian and Meso-/Cenozoic salt formations are represented in wide parts of the German geologic underground (Reinhold & Hammer 2016). They are of interest for cavern storage of oil and gas as well as of renewable energies (in form of compressed air or hydrogen). For industrial exploration purposes, more detailed data about the composition, barrier properties, as well as the genesis and deformation of the rocks is needed. In central Northern Germany, salt rocks from the Upper Rotliegend are implemented in diapir structures together with salt formations from the Zechstein. Rotliegend salt rocks are characterized by halite that contains patches of detrital material which account for 5 to 60 vol.% of the rock. They show a characteristic red to purple color. Drill cores containing Rotliegend halite rocks from different locations were investigated in this study by using petrographical and microstructural methods. The halite shows different fabric types: (i) euhedral to hypidiomorphic grains with grain sizes up to several millimeters, (ii) polygonal grains with smaller grain sizes between 0.1 and 3 mm, and (iii) fibrous halite. Halite grain boundaries are decorated with fluid inclusions, especially around the contact to detrital material. Subgrains in halite are abundant in all investigated samples and show average sizes between 140 µm and 217 µm. These correspond to average differential stresses of 1 MPa to 1.45 MPa (Carter et al. 1993, Schléder & Urai 2005). The detrital material consists of clasts of quartz, feldspar, mica, carbonates and metal oxides with grain sizes of clay to silt fraction. In some samples, the detrital components show internal deformation by folding and fracturing. Depending on the location, different quantities of authigenic evaporite minerals, like carbonate and anhydrite, formed. Fractures are filled with halite, anhydrite and celestine. The different types of halite fabric are an indication of locally different deformational behavior of the

  16. Gas adsorption on crushed quartz and basalt. [in vacuum

    Science.gov (United States)

    Barker, C.; Torkelson, B. E.

    1975-01-01

    The new surfaces generated by crushing rocks and minerals adsorb gases. Different gases are adsorbed to different extents so that both the total amount and composition of the released gases are changed. This affects the interpretation of the composition of the gases obtained by vacuum crushing lunar basalts, meteorites and minerals with fluid inclusions.

  17. Electronic and Optical Properties of Rock-Salt A1N under High Pressure via First-Principles Analysis

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wei; CHEN Xiang-Rong; CAI Ling-Cang; GOU Qing-Quan

    2008-01-01

    Electronic and optical properties of rock-salt A1N under high pressure are investigated by first -principles method based on the plane-wave basis set. Analysis of band structures suggests that the rock-salt AIN has an indirect gap of 4.53 eV, which is in good agreement with other results. By investigating the effects of pressure on the energy gap, the different movement of conduction band at X point below and above 22.5 GPa is predicted. The optical properties including dielectric function, absorption, reflectivity, and refractive index are also calculated and analyzed. It is found that the rock-salt AIN is transparent from the partially ultra-violet to the visible light area and hardly does the transparence affected by the pressure. Furthermore, the curve of optical spectrum will shift to high energy area (blue shift) with increasing pressure.

  18. Rock salt mass in the Paleoproterozoic sequence of the Onega trough in Karelia (from the Onega parametric well data)

    Science.gov (United States)

    Morozov, A. F.; Khakhaev, B. N.; Petrov, O. V.; Gorbachev, V. I.; Tarkhanov, G. V.; Tsvetkov, L. D.; Erinchek, Yu. M.; Akhmedov, A. M.; Krupenik, V. A.; Sveshnikova, K. Yu.

    2010-11-01

    A thick (200 m) rock salt mass covering Late Archean granitoids was exposed for the first time in the Early Proterozoic volcanogenic-sedimentary formations in the Onega trough of the east Baltic Shield by the Onega parametric well. The mineral composition of salts, their geochemical features, and the isotopic composition of carbonate carbon and oxygen have been studied. After fluid inclusions present in salts, their metamorphism temperature and isotopic composition of helium and argon were determined. The obtained results give evidence of the fact that rock salts and magnesites associated with them were formed in an evaporate basin with participation of deep crustal processes. The age of the underlying granitoids (2.716 ± 9 Ma) is determined using the Pb—Pb method.

  19. Authigenic K-feldspar in salt rock (Haselgebirge Formation, Eastern Alps)

    Science.gov (United States)

    Leitner, Christoph

    2015-04-01

    The crystallisation of authigenic quartz under low temperature, saline conditions is well known (Grimm, 1962). Also the growth of low temperature authigenic feldspar in sediments is a long known phenomenon (Kastner & Siever, 1979; Sandler et al., 2004). In this study we intend to show that halite (NaCl) is a major catalyser for authigenic mineral growth. During late Permian (c. 255-250 Ma), when the later Eastern Alps were located around north of the equator, the evaporites of the Haselgebirge Formation were deposited (Piller et al., 2004). The Haselgebirge Fm. consists in salt mines of a two-component tectonite of c. 50 % halite and 50 % sedimentary clastic and other evaporite rocks (Spötl 1998). Most of the clastic rocks are mud- to siltstones ("mudrock"). During this study, we investigated rare sandstones embedded in salt rock form four Alpine salt mines. Around 40 polished thin sections were prepared by dry grinding for thin section analysis and scanning electron microscopy. The sandstones consist mainly of quartz, K-feldspar, rock fragments, micas, accessory minerals and halite in the pore space. They are fine grained and well sorted. Mudrock clasts in sandstone were observed locally, and also coal was observed repeatedly. Asymmetric ripples were found only in the dimension of millimeters to centimeters. Euhedral halite crystals in pores indicate an early presence of halite. During early diagenesis, authigenic minerals crystallized in the following chronological order. (1) Where carbonate (mainly magnesite) occurred, it first filled the pore space. Plant remains were impregnated with carbonate. (2) Halite precipitated between the detritic sandstone grains. Carbonate grains can be completely embedded in halite. (3) K-feldspar and quartz grains usually expose a detritic core and a later grown euhedral inclusion free rim. Euhedral rims of K-feldspar often also enclose a halite core. K-feldspar replaced the pre-existing halite along former grain boundaries of

  20. Thermal properties of rock salt and quartz monzonite to 573{sup 0}K and 50-MPa confining pressure

    Energy Technology Data Exchange (ETDEWEB)

    Durham, W.B.; Abey, A.E.

    1981-03-18

    Measurements of thermal conductivity, thermal diffusivity, and thermal linear expansion have been made on two rock types, a rock salt and a quartz monzonite, at temperatures from 300 to 573{sup 0}K and confining pressures from 10 to 50 MPa. The samples were taken from deep rock formations under consideration as possible sites for a nuclear waste repository - the rock salt from a domal salt formation at Avery Island, Louisiana, and the quartz monzonite from the Climax Stock, Nevada Test Site, Nevada. The testing temperature and pressures are meant to bracket conditions expected in the repository. In both rock types, the thermal properties show a strong dependence upon temperature and a weak or non-dependence upon confining pressure. Thermal conductivity and diffusivity both decrease with increasing temperature in approximately linear fashion for samples which have not been previously heated. At 50 MPa in both rocks this decrease closely matches the measured or expected intrinsic (crack-free) behavior of the material. Preliminary indications from the quartz monzonite suggest that conductivity and diffusivity at low pressure and temperature may decrease as a result of heat treatment above 400{sup 0}K.

  1. Experimental deformation of coarse-grained rock salt to high strain

    Science.gov (United States)

    Linckens, J.; Zulauf, G.; Hammer, J.

    2016-08-01

    The processes and deformation mechanisms (e.g., dislocation creep, pressure solution, grain boundary sliding, and recrystallization) of rock salt are still a matter of debate. In order to fill this gap, high strain constriction experiments at 345°C, atmospheric pressure and a strain rate of 10-7 s-1 have been conducted on natural halite cuboids (60 × 60 × 45 mm) from the Morsleben mine of Northern Germany. Most samples were almost single crystals and contain a small amount of smaller grains (10-26%). The grain boundaries are decorated with fluid inclusions. The experiments were stopped at different final strains (ɛy = z of 10, 20, 30, and 40%) corresponding to a maximum strain (ɛx) range of 20-170%. The halite is deformed by dislocation creep, and the size of developed subgrains corresponds to the applied stress. The combined Schmid factor and subgrain boundary analysis indicate that slip was largely accommodated by the {110} slip systems, with possible minor contribution by slip on the {100} slip systems. Some of the deformed samples show evidence of grain boundary migration. In addition, subgrains with small misorientations form that result in large cumulative misorientations within a single grain (>40°). However, no subgrain rotation recrystallization is observed (i.e., misorientation angles are <10°). All the experiments show strain hardening, suggesting that recrystallization by grain boundary migration was not extensive and did not reset the microstructure. The experiments show that high finite strain in coarse-grained relatively dry rock salt can be accommodated by dislocation creep, without extensive dynamic recrystallization.

  2. Stabilization of rock salt ZnO nanocrystals by low-energy surfaces and Mg additions : A first-principles study

    NARCIS (Netherlands)

    Koster, Rik S.; Fang, Changming M.; Dijkstra, Marjolein; Van Blaaderen, Alfons; Van Huis, Marijn A.

    2015-01-01

    Whereas bulk zinc oxide (ZnO) exhibits the wurtzite crystal structure, nanoscale ZnO was recently synthesized in the rock salt structure by addition of Mg. Using first-principles methods, we investigated two stabilization routes for accessing rock salt ZnO. The first route is stabilization by Mg add

  3. Crushed Stone Operations

    Data.gov (United States)

    Department of Homeland Security — This map layer includes crushed stone operations in the United States. These data were obtained from information reported voluntarily to the USGS by the aggregate...

  4. Gas Permeation Models for Dilatant Deformation of Rock Salt under Deviatoric Stress Conditions

    Directory of Open Access Journals (Sweden)

    Guenter Pusch

    2007-01-01

    Full Text Available Permeability of 30 rock salt cores were measured under various deviatoric stress conditions. A triaxial cell was designed and built to measure the hydraulic properties such as the pore volume and permeability during the compression experiments. To determine variations in the pore volume, a high precision pump was used and the pore volume changes as well as the gas permeabilities were recorded continuously as a function of time and stresses. A permeability reduction in the compression stage is not obvious although the decrease of pore volume appears to be a controlling phenomenon of the compression. Similarly to previous studies, a spontaneous increase in the permeability was observed shortly after the dilatancy boundary was exceeded, separating the compression from the dilatant deformation phase. At the end of the dilatant deformation, the permeability reaches a plateau value which afterward remains approximately a constant for low stress rates up to the fracture pressure. This allows the percolation of gas along the extended grain boundaries of the salt crystals and through the inter-crystalline flow paths and yields an increase of the permeability of 3 to 6 tens of order. Combined acoustic emission measurements performed with 8 sensors showed that the percolation begins equally throughout the core at the same time. The dilatancy and permeability are found to be controlled by many factors,most importantly by the minimal principal stresses. The end porosities of the stressed cores were correlated with the permeability in the form of a Kozeny-Carman type relationship. Semi-empirical and percolation flow models were applied to match the observed flow characteristics of cores with corresponding properties of the excavation damaged zone in the Asse salt mine.

  5. Building the 3D Geological Model of Wall Rock of Salt Caverns Based on Integration Method of Multi-source data

    Science.gov (United States)

    Yongzhi, WANG; hui, WANG; Lixia, LIAO; Dongsen, LI

    2017-02-01

    In order to analyse the geological characteristics of salt rock and stability of salt caverns, rough three-dimensional (3D) models of salt rock stratum and the 3D models of salt caverns on study areas are built by 3D GIS spatial modeling technique. During implementing, multi-source data, such as basic geographic data, DEM, geological plane map, geological section map, engineering geological data, and sonar data are used. In this study, the 3D spatial analyzing and calculation methods, such as 3D GIS intersection detection method in three-dimensional space, Boolean operations between three-dimensional space entities, three-dimensional space grid discretization, are used to build 3D models on wall rock of salt caverns. Our methods can provide effective calculation models for numerical simulation and analysis of the creep characteristics of wall rock in salt caverns.

  6. Clinopyroxene application in petrogenesis identification of volcanic rocks associated with salt domes from Shurab (Southeast Qom

    Directory of Open Access Journals (Sweden)

    Somayeh Falahaty

    2016-07-01

    Full Text Available Introduction The study area is located in the Shurab area that is about 50 Km Southeast of Qom. Volcanic rocks of the Shurab area have basaltic composition that is associated with salt and marl units. Igneous rocks of the Shurab area have not been comprehensively studied thus far. Clinopyroxene composition of volcanic rocks, and especially the phenocrysts show Magma chemistry and can help to identify magma series (Lebas, 1962; Verhooge, 1962; Kushiro, 1960, Leterrier et al., 1982, tectonic setting (Leterrier et al., 1982; Nisbet and Pearce, 1977 as well as temperature formation and pressure of rock formation. Some geologists have estimated temperature of clinopyroxene formation by clinopyroxene composition (Adams and Bishop, 1986 and clinopyroxene-olivine couple. So, clinopyroxene is used in this study in order to identify magma series, tectonic setting, plus the temperature and pressure of volcanic rocks of the Shurab. Material and method Clinopyroxene analyses were conducted by wavelength-dispersive EPMA (JEOL JXA-8800R at the Cooperative Centre of Kanazawa University (Japan. The analyses were performed under an accelerating voltage of 15 kV and a beam current of 20 nA. The ZAF program was used for data corrections. Natural and synthetic minerals of known composition were used as standards. The Fe3+ content in minerals was estimated by Droop method (Droop, 1987. Discussion In the Shurab area, the volcanic rocks area with basaltic composition are located 50 km Southeast of Qom. Their age is the early Oligocene and they are associated with the salty marl units of the Lower Red Formation (LRF. The hand specimens of the studied rocks look green. These rocks are intergranular, microlitic, porphyric, vitrophyric and amygdaloidal and they consist of olivine, pyroxene and plagioclase. Accessory minerals contain sphene, apatite and opaque. According to Wo-En-Fs diagram (Morimoto, 1988, clinopyroxenes indicate diopside composition. Clinopyroxenes are

  7. Crush Test Abuse Stand

    Science.gov (United States)

    Collins, Jacob; Jeevarajan, Judith; Salinas, Mike

    2011-01-01

    The purpose of this system is to simulate an internal short on battery cells by causing deformation (a crushing force) in a cell without penetration. This is performed by activating a hydraulic cylinder on one side of a blast wall with a hydraulic pump located on the other. The operator can control the rate of the crush by monitoring a local pressure gauge connected to the hydraulic cylinder or a load cell digital display located at the hydraulic pump control area. The internal short simulated would be considered a worst-case scenario of a manufacturer fs defect. This is a catastrophic failure of a cell and could be a very destructive event. Fully charged cells are to have an internal short simulated at the center of the length of the cell (away from terminals). The crush can be performed with a .- to 1-in. (.0.6- to 2.5-cm) rod placed crossways to the cell axis, causing deformation of the cell without penetration. The OCV (open-circuit voltage) and temperature of the cells, as well as the pressure and crushing force, are recorded during the operation. Occurrence of an internal short accompanied by any visible physical changes such as venting, fires, or explosions is reported. Typical analytical data examined after the test would be plots of voltage, temperature, and pressure or force versus time. The rate of crushing force can be increased or decreased based on how fast the operator pumps the hydraulic pump. The size of cylinder used to compress the battery cell can be easily changed by adding larger or smaller fittings onto the end of the hydraulic cylinder based on the battery/cell size being tested. The cell is crushed remotely and videotaped, allowing the operator to closely monitor the situation from a safe distance.

  8. Energy Saving and Pollution Alleviation by Replacement of Crushed Rock with Municipal Solid Waste Incineration%焚烧炉渣集料用于道路铺筑的节能减排定量

    Institute of Scientific and Technical Information of China (English)

    陈德珍; 耿翠洁; 孙文州; 施惠生

    2011-01-01

    The construction project of section No. 17th K11 + 203 ~ K11 + 413, north highway to Shanghai Pudong international airport, where municipal solid waste incineration (MSWI) bottom ash was used as aggregate to replace part of crushed natural rock, was taken as an example for energy saving and pollution alleviation analysis. Life cycle assessment(LCA) was performed for this replacement to evaluate the differences in energy consumption and emissions. The results show that 53.9% of natural rock resource can be saved by using MSWI bottom ash as part of aggregate in road base construction; the energy consumption can be reduced by around 47% compared with road construction with all aggregate materials coming from graded crushed rock. Also the emissions to air and discharge of COD, N-total,oil,and phenol to ground water that are related to energy production & consumption are reduced by 42% to 50%. However,recycling MSWI bottom ash as part of aggregate in road construction could lead to an increase in leaching heavy metals of Cd,Cr,Cu,Ni,Pb and Zn, while the leaching of arsenic is reduced.%以上海浦东国际机场北通道工程的17标K11+203~K11+413试验段为例,在资源、能源消耗以及环境排放方面,从生命周期分析的角度对用垃圾焚烧(MSWI)炉渣替代部分碎石集料铺路和用纯碎石铺路这两种工艺进行了分析比较.结果表明,利用垃圾焚烧炉渣替代碎石铺路可以节约53.9%的石料资源,同时降低约47%的能耗;与能源和资源节约相对应,上述工艺的各种大气污染物以及有机污染物如化学需氧量(COD)、总氮、苯酚类物质等的生命周期排放都较纯碎石集料工艺低42%~50%.但在没有控制措施的条件下以焚烧炉渣替代碎石集料铺路会导致Cd,Cr,Cu,Ni,Pb,Zn等重金属浸出量有一定增加,砷的浸出量降低.

  9. The Triple Salt Sr14[Ta4N13][TaN4]O-A Nitridotantalate Oxide with 19-fold Rock Salt Superstructure.

    Science.gov (United States)

    Wörsching, Matthias; Daiger, Martin; Hoch, Constantin

    2017-02-21

    A new structure motif in nitridometalate chemistry is the tetracatena-nitridotantalate anion [Ta4N13](19-). It occurs in the crystal structure of the triple salt Sr14[Ta4N13][TaN4]O (monoclinic, space group P21/c with a = 15.062(2) Å, b = 7.2484(6) Å, c = 24.266(3) Å, and β = 97.280(10)(o)) together with ortho-tantalate and isolated oxide anions. Synthesis followed a new approach with employment of Sr surplus and reductive conditions aimed at the preparation of subvalent compounds. The new structure type was established on the basis of single-crystal X-ray diffraction data and also Rietveld refinement. It is a complex superstructure of the rock salt structure type with Ta and Sr atoms forming the face-centered cubic packing and N and O atoms occupying 18/19 of the octahedral voids. We discuss structure and stability of the triple salt with respect to other known nitridometalates and the use of this triple salt for preparative access toward new metal-rich compounds in this field.

  10. Heavy Metal Contamination and Salt Efflorescence Associated With Decorative Landscaping Rocks, Las Vegas, Nevada: The Need for Regulations

    Science.gov (United States)

    Mrozek, S. A.; Buck, B. J.; Brock, A. L.

    2004-12-01

    Las Vegas, Nevada is one of the fastest growing cities in the United States. Faced with water restrictions, decorative rock xeroscaping has become a very popular form of landscaping. Currently, there are no regulations controlling the geochemistry of the decorative rocks that can be used for these purposes. In this study, we examined three sites containing two different decorative rock products. The landscaping rocks, underlying soil, and surface salt crusts were analyzed to determine their mineralogy and chemistry. Methods of analysis include scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDS), X-ray diffraction (XRD), inductively coupled plasma atomic emission spectroscopy (ICP), thin section analysis, and laser particle size analysis (LPSA). Preliminary results indicate the presence of halite (NaCl), bloedite (Na2Mg(SO4)2 4H2O), a hydrated magnesium sulfate, and possibly copper sulfate and copper chloride mineral phases in the surface salt crusts. Both copper minerals are regarded as hazardous substances by the Occupational Safety and Health Administration (OSHA) and the Environmental Protection Agency (EPA); these agencies have established minimum exposure limits for human contact with these substances. Copper sulfate and copper chloride are not naturally occurring minerals in the soils of the Las Vegas Valley, and analyses indicate that their formation may be attributed to the mineralogy of the decorative landscaping rocks. Further testing is needed to characterize this potential health hazard; however the preliminary results of this study demonstrate the need for regulations controlling the geochemistry of decorative rocks used for urban landscaping.

  11. Computer Simulation Methods for Crushing Process in an Jaw Crusher

    Science.gov (United States)

    Il'ich Beloglazov, Ilia; Andreevich Ikonnikov, Dmitrii

    2016-08-01

    One of the trends at modern mining enterprises is the application of combined systems for extraction and transportation of the rock mass. Given technology involves the use the conveyor lines as a continuous link of combined technology. The application of a conveyor transport provides significant reduction of costs for energy resources, increase in labor productivity and process automation. However, the use of a conveyor transport provides for certain requirements for the quality of transported material. The maximum size of the rock mass pieces is one of the basic parameters for it. The crushing plants applies as a coarse crushing followed by crushing the material to the maximum size of piece which possible to use for conveyor transport. It is often represented by jaw crushers. Modelling of crushing process in jaw crushers allows to maximally optimize workflow and increase efficiency of the equipment at the further transportation and processing of rocks. We studied the interaction between walls of the jaw crusher and bulk material by using discrete element method (DEM) in this paper. The article examines the process of modeling by stages. It includes design of the crusher construction in solid and surface modeling system. Modelling of the crushing process based on the experimental data received via the crushing unit BOYD. The process of destruction and particle size distribution in the study was done. Analysis of research results shows a comparability of actual experiment and modeling process.

  12. Development of mechanical-hydraulic models for the prediction of the long-term sealing capacity of concrete based sealing materials in rock salt. Project Titel LASA

    Energy Technology Data Exchange (ETDEWEB)

    Czaikowski, Oliver; Dittrich, Juergen; Hertes, Uwe; Jantschik, Kyra; Wieczorek, Klaus; Zehle, Bernd

    2016-08-15

    The research work leading to these results has received funding from the German Federal Ministry of Economic Affairs and Energy (BMWi) under contract no. 02E11132. This report presents the current state of laboratory investigations and modelling activities related to the LASA project. The work is related to the research and development of plugging and sealing for repositories in salt rock and is of fundamental importance for the salt option which represents one of the three European repository options in addition to the clay rock and the crystalline rock options.

  13. 岩盐的蠕变变形规律及参数试验研究%Experimental Study on Creep Deformation Properties and Parameters of Rock Salt

    Institute of Scientific and Technical Information of China (English)

    林斌

    2013-01-01

    以娄庄盐矿第16层岩盐为研究对象,采用单试件多级加载方式,试验研究了该岩盐的单轴蠕变变形特征。结果表明,岩盐的蠕变变形可以采用形如y=a(1-e-bx )的指数函数描述,蠕变参数a和b可以用蠕变应力σ的幂函数来描述。岩盐的长期强度约为瞬时单轴强度的68%。%The 16th layer of rock salt in Louzhuang salt mine is an object of study.The properties of uniaxial creep deformation of the rock salt are studied by the method of exerting multistage loads in single sample of rock salt.The results show that the creep properties of rock salt can be described by the function as y=a(1-e-bx ),at the same time,the creep parameters of a and b are also described by power function of σ.The long-term strength of rock salt is just about 68% to the instantaneous strength.

  14. Crushing effects on TL and OSL on quartz: relevance to fault dating

    Energy Technology Data Exchange (ETDEWEB)

    Toyoda, S. E-mail: toyoda@dap.ous.ac.jp; Rink, W.J.; Schwarcz, H.P.; Rees-Jones, J

    2000-12-15

    The effect of crushing on the TL and OSL signals in quartz was investigated to examine the feasibility of using OSL and TL for dating of faulted rocks. 275 deg. C TL signals were not reduced by crushing by hand (mortar and pestle), in a pellet die press, or using an automatic mortar and pestle, but the sensitivity of the 100 deg. C TL signal to a test dose decreased in crushed samples. Green light-stimulated OSL signal intensities were not decreased after crushing, but showed strongly increased inter-aliquot variability after crushing. We concluded that OSL and TL in quartz might be useful to characterize the crushing history of quartz in fault rocks, but their usefulness in dating fault events was not evident because we did not find evidence of signal zeroing under the conditions used in this study.

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

    Science.gov (United States)

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

    2014-03-01

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

  16. 层状盐岩力学特性与蠕变机理研究%Research on Mechanics Properties and Creep Mechanism of Layered Salt Rock

    Institute of Scientific and Technical Information of China (English)

    徐月生; 陈建忠; 王永志

    2012-01-01

    对层状盐岩力学特性进行实验与分析,获取相应的力学特征参数,是盐岩地下溶腔蠕变特性数值模拟的必要步骤,是数值计算中力学模型的组成要素。本文通过单轴压缩、三轴压缩和压缩蠕变等实验,获取层状盐岩短期强度特性和长期蠕变特性的力学特征参数,为盐岩蠕变模拟提供必要的参数支持。在此基础上,本文对层状盐岩蠕变机理进行分析,并将对盐岩蠕变率方程进行解析,为构建盐岩蠕变本构模型作铺垫。%the mechanics properties of layered rock is tested and analyzed to obtain the corresponding mechanics characteristic parameters.This is the necessary step of numerical simulation of the creep properties of salt rock in underground cavity and the composing element of the mechanics model in numerical calculation.This essay,via the tests such as single-axis compression,three-axis compression,compression creep,etc.,obtains the mechanics characteristic parameters of the short-term intensity characteristics and long-term creep characteristics of layered salt rock to provide necessary parameter support to salt rock creep simulation.On the basis of this,this essay analyzes the creep mechanism of layered salt rock and parses the equation of salt rock creep rate to lay foundation for the construction of salt rock creep constitutive?model.

  17. Measurements of radio propagation in rock salt for the detection of high-energy neutrinos

    Science.gov (United States)

    Connolly, Amy; Goodhue, Abigail; Miki, Christian; Nichol, Ryan; Saltzberg, David

    2009-02-01

    We present measurements of the transmission of radio/microwave pulses through salt in the Cote Blanche salt mine operated by the North American Salt Company in St. Mary Parish, Louisiana. These results are from data taken in the southwestern region of the 1500 ft (457 m) deep level of the mine on our third and most recent visit to the mine. We transmitted and received a fast, high-power, broadband pulse from within three vertical boreholes that were drilled to depths of 100 ft (30 m) and 200 ft below the 1500 ft level using three different pairs of dipole antennas whose bandwidths span 125-900 MHz. By measuring the relative strength of the received pulses between boreholes with separations of 50 and 169 m, we deduce the attenuation of the signal attributed to the salt medium. We fit the frequency dependence of the attenuation to a power law and find the best fit field attenuation lengths to be 93±7m at 150 MHz, 63±3m at 300 MHz, and 36±2m at 800 MHz. This is the most precise measurement of radio attenuation in a natural salt formation to date. We assess the implications of this measurement for a future neutrino detector in salt.

  18. Se EXAFS study of the elevated wurtzite to rock salt structural phase transition in CdSe nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Tolbert, S.H.; Alivisatos, A.P. [Lawrence Berkeley Lab., CA (United States)]|[California Univ., Berkeley, CA (United States). Dept. of Chemistry

    1993-09-01

    High pressure Se EXAFS data has been obtained on 2.7 nm radius CdSe semiconductor nanocrystals. This system is observed to undergo a solid-solid phase transition at 6.5 GPa which is approximately twice the reported value for bulk CdSe. In combination with high pressure optical absorption experiments, EXAFS data can be used to identify the high-pressure phase structure as rock salt. EXAFS data can be fit with equations of state to yield pressure volume curves. Resultant values of bulk modulus and its derivative with respect to pressure are B{sub o} = 37 {plus_minus} 5 GPa and B{sub o}{prime} = 11 {plus_minus} 3. A thermodynamic model for the data is presented in which the internal energy in each phase is modified by a surface energy term. Differences in surface energy are used to explain the elevation in phase transition pressure. The model can be used to estimate a value for the surface energy in the rock salt phase; 1.9 {plus_minus} 0.3 N/m is obtained in comparison to 0.9 {plus_minus} 0. 1 N/m for the wurtzite phase.

  19. Map data and Unmanned Aircraft System imagery from the May 25, 2014 West Salt Creek rock avalanche in western Colorado

    Science.gov (United States)

    Coe, Jeffrey A.; Baum, Rex L.; Allstadt, Kate; Kochevar, Bernard; Schmitt, Robert G.; Morgan, Matthew L.; White, Jonathan L.; Stratton, Benjamin T.; Hayashi, Timothy A.; Kean, Jason W.

    2016-01-01

    On May 25, 2014, a rain-on-snow induced rock avalanche occurred in the West Salt Creek Valley on the northern flank of Grand Mesa in western Colorado. The avalanche traveled 4.6 km down the confined valley, killing 3 people. The avalanche was rare for the contiguous U.S. because of its large size (54.5 Mm3) and long travel distance. To understand the avalanche failure sequence, mechanisms, and mobility, we mapped landslide structures, geology, and ponds at 1:1000-scale. We used high-resolution, Unmanned Aircraft System (UAS) imagery from July 2014 as a base for our field mapping. Here we present the map data and UAS imagery. The data accompany an interpretive paper published in the journal Geosphere. The full citation for this interpretive journal paper is: Coe, J.A., Baum, R.L., Allstadt, K.E., Kochevar, B.F., Schmitt, R.G., Morgan, M.L., White, J.L., Stratton, B.T., Hayashi, T.A., and Kean, J.W., 2016, Rock avalanche dynamics revealed by large-scale field mapping and seismic signals at a highly mobile avalanche in the West Salt Creek Valley, western Colorado: Geosphere, v. 12, no. 2, p. 607-631,  doi:10.1130/GES01265.1. 

  20. 井矿盐生产节能减排浅析%Analysis of energy saving and emission reduction in well and rock salt production

    Institute of Scientific and Technical Information of China (English)

    朱旭初

    2014-01-01

    文章依据井矿盐生产的实际情况,从工艺、设备、操作、管理4个方面分析了井矿盐生产节能减排的具体措施和办法。%The management of specific measures and methods of energy saving and emission reduction in well and rock salt production was studied from the four aspects of process such as emission, equipment, operation,management based on the actual situations of well and rock salt industry production.

  1. Measurements of radio propagation in rock salt for the detection of high-energy neutrinos

    CERN Document Server

    Connolly, Amy; Miki, Christian; Nichol, Ryan; Saltzberg, David

    2008-01-01

    We present measurements of the transmission of radio/microwave pulses through salt in the Cote Blanche salt mine operated by the North American Salt Company in St. Mary Parish, Louisiana. These results are from data taken in the southwestern region of the 1500 ft. (457 m) deep level of the mine on our third and most recent visit to the mine. We transmitted and received a fast, high-power, broadband pulse from within three vertical boreholes that were drilled to depths of 100 ft. (30 m) and 200 ft. below the 1500 ft. level using three different pairs of dipole antennas whose bandwidths span 125 to 900 MHz. By measuring the relative strength of the received pulses between boreholes with separations of 50 m and 169 m, we deduce the attenuation of the signal attributed to the salt medium. We fit the frequency dependence of the attenuation to a power law and find the best fit field attenuation lengths to be 93 \\pm 7 m at 150 MHz, 63 \\pm 3 m at 300 MHz, and 36 \\pm 2 m at 800 MHz. This is the most precise measuremen...

  2. Concerning the gas presence in salt rocks of the second potassium stratum of the mine field of the IV RU of the Starobinsk deposit

    Energy Technology Data Exchange (ETDEWEB)

    Bylino, L.V.; Nesterova, T.Y.; Yevtushenko, Y.A.

    1981-01-01

    Because of the operational entry of the fourth mine field of the Starobinsk deposit, the necessity arose of studying the composition and volume of microincluded gases in order to determine the total gas presence in the potassium strata and to predict its explosive danger. The microinclusions of gases were studied in samples selected from the salt rocks of a normal section and the zones of the positioning of sylvinite layers through a method of solution of the samples and analysis of the liberated gas in chromatographs. It is established that salt rocks of the placement zones are different in the content of the microinclusions of the gases from the rocks of the normal section. A specific feature of the microinclusions of gases in the presence of helium and hydrogen, whose increased volumes are characteristic for sylvinites of the upper and lower sylvinite layers. Noted is a regularity in the relation between the helium and hydrogen in the normal section of the second potassium layer from the increased contents of these gases in the upper sylvinite layer with a subsequent reduction in their volumes to the traces in the basement rock salt. In the rock salt of the sylvinite layer, placement zones methane is detected in the very same volumes as in the sylvinites, while in the intermediate and basement rock salt, traces of it are only sometimes noted. The obtained materials will be used in the development of prerequisites for the deduction and study of the explosive zones within the mine field of the IV RU of the Starobinsk deposit.

  3. Simulation of rock salt dissolution and its impact on land subsidence

    Directory of Open Access Journals (Sweden)

    A. Zidane

    2013-10-01

    Full Text Available Extensive land subsidence can occur due to subsurface dissolution of evaporites such as halite and gypsum. This paper explores techniques to simulate the salt dissolution forming an intrastratal karst, which is embedded in a sequence of carbonates, marls, anhydrite and gypsum. A numerical model is developed to simulate laminar flow in reactive fractures. The numerical model is based on the laminar steady state Stokes flow equation, and the advection dispersion transport equation coupled with the dissolution equation. The flow equation is solved using the nonconforming Crouzeix–Raviart (CR finite element approximation for the Stokes equation. For the transport equation, a combination between Discontinuous Galerkin Method and Multipoint Flux Approximation Method is proposed. The numerical effect of the dissolution is considered by using a dynamic mesh variation that increases the size of the mesh based on the amount of dissolved salt. The numerical method is applied to a 2-D geological cross section representing a Horst and Graben structure in the Tabular Jura of north-western Switzerland. It simulates salt dissolution within the geological section and predicts the amount of vertical dissolution as an indicator of subsidence that could occur. Simulation results showed that the highest dissolution amount is observed near the normal fault zones, and therefore the highest subsidence rates are expected above fault zones.

  4. Probabilistic methods as a tool aiding dimensioning drift and shaft seals for a repository in rock salt

    Energy Technology Data Exchange (ETDEWEB)

    Roehlig, Klaus-Juergen; Plischke, Elmar; Li, Xiaoshuo [TU Clausthal, Clausthal-Zellerfeld (Germany). Inst. of Disposal Research (IELF)

    2015-07-01

    For repositories in rock salt, demonstrating the integrity of drift and shaft seals is an indispensable part of the long-term safety case. In this study, probabilistic methods are applied to assess the fictitious abutment length for a shaft seal and the effective permeability of a drift seal (dam), i.e. the integral entity for the whole structure including contact zone and damaged salt zone. For the seal permeability, the question arises how to derive it based on permeability measurements with a limited number of samples due to cost restrictions. Furthermore, it is of interest which conclusions can be derived regarding the minimum length of drift seals if the failure probability should be smaller than e.g. 10{sup -4}. Based on numerical experiments it was demonstrated that small-scale measurements can be upscale using known averaging methods. This suggests that dimensioning can be carried out based on cautions average estimates and the required reliability statement (e.g. about a failure probability smaller than e.g. 10{sup -4}) can be derived for realistic dam lengths. However, due to the limited amount of data available there are remaining uncertainties concerning the underlying model assumptions.

  5. Measurement of a Phase of a Radio Wave Reflected from Rock Salt and Ice Irradiated by an Electron Beam for Detection of Ultra-High-Energy Neutrinos

    CERN Document Server

    Chiba, Masami; Tanikawa, Takahiro; Yano, Hiroyuki; Yabuki, Fumiaki; Yasuda, Osamu; Chikashige, Yuichi; Kon, Tadashi; Shimizu, Yutaka; Watanabe, Souichirou; Utsumi, Michiaki; Fujii, Masatoshi

    2013-01-01

    We have found a radio-wave-reflection effect in rock salt for the detection of ultra-high energy neutrinos which are expected to be generated in Greisen, Zatsepin, and Kuzmin (GZK) processes in the universe. When an UHE neutrino interacts with rock salt or ice as a detection medium, a shower is generated. That shower is formed by hadronic and electromagnetic avalanche processes. The energy of the UHE neutrino shower converts to thermal energy through ionization processes. Consequently, the temperature rises along the shower produced by the UHE neutrino. The refractive index of the medium rises with temperature. The irregularity of the refractive index in the medium leads to a reflection of radio waves. This reflection effect combined with the long attenuation length of radio waves in rock salt and ice would yield a new method to detect UHE neutrinos. We measured the phase of the reflected radio wave under irradiation with an electron beam on ice and rock salt powder. The measured phase showed excellent consis...

  6. A Variable-Parameter Creep Damage Model Incorporating the Effects of Loading Frequency for Rock Salt and Its Application in a Bedded Storage Cavern

    Science.gov (United States)

    Ma, Linjian; Wang, Mingyang; Zhang, Ning; Fan, Pengxian; Li, Jie

    2017-09-01

    Laboratory tests were conducted to assess the effects of the loading frequency on the time-dependent behavior and damage properties of rock salt under confining stress states. Axial two-stage irreversible deformation based on the loci of the minimum load of each cycle was observed, and this observation was similar to the result of conventional creep tests under static loads. The unloading modulus decreased exponentially with respect to time, and the damage variable was represented in terms of the decay of the material stiffness. To account for the effects of the loading frequency on the time-dependent degradation of rock salt, a unified damage evolution equation was formulated based on the experimental results. A creep damage model of rock salt was proposed by introducing non-stationary modular components into the Burgers viscoelastic model. Numerical simulation was performed using the newly developed model to evaluate the stability and serviceability of a storage cavern in a bedded salt formation under various loading scenarios. The simulated results indicate that a lower injection-withdrawal frequency results in a greater volume convergence rate and a wider dilatancy region of the storage cavern. Additionally, the stress concentration and dilatancy of the surrounding rock mass extend much deeper into the mudstone interbeds than into other regions of the cavern.

  7. Preparation of Al-Si Master Alloy by Electrochemical Reduction of Volcanic Rock in Cryolite Molten Salt

    Science.gov (United States)

    Liu, Aimin; Shi, Zhongning; Xu, Junli; Hu, Xianwei; Gao, Bingliang; Wang, Zhaowen

    2016-06-01

    Volcanic rock found in the Longgang Volcano Group in Jilin Province of China has properties essentially similar to Apollo lunar soils and previously prepared lunar soil simulants, such as Johnson Space Center Lunar simulant and Minnesota Lunar simulant. In this study, an electrochemical method of preparation of Al-Si master alloy was investigated in 52.7 wt.%NaF-47.3 wt.%AlF3 melt adding 5 wt.% volcanic rock at 1233 K. The cathodic electrochemical process was studied by cyclic voltammetry, and the results showed that the cathodic reduction of Si(IV) is a two-step reversible diffusion-controlled reaction. Si(IV) is reduced to Si(II) by two electron transfers at -1.05 V versus platinum quasi-reference electrode in 52.7 wt.%NaF-47.3 wt.%AlF3 molten salt adding 5 wt.% volcanic rock, while the reduction peak at -1.18 V was the co-deposition of aluminum and silicon. In addition, the cathodic product obtained by galvanostatic electrolysis for 4 h was analyzed by means of x-ray diffraction, x-ray fluorescence, scanning electron microscopy and energy dispersive spectrometry. The results showed that the phase compositions of the products are Al, Si, Al5FeSi, and Al3.21Si0.47, while the components are 90.5 wt.% aluminum, 4.4 wt.% silicon, 1.9 wt.% iron, and 0.2 wt.% titanium.

  8. 21 CFR 137.195 - Crushed wheat.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Crushed wheat. 137.195 Section 137.195 Food and... Related Products § 137.195 Crushed wheat. Crushed wheat, coarse ground wheat, is the food prepared by so crushing cleaned wheat other than durum wheat and red durum wheat that, when tested by the method...

  9. 岩盐弹塑性损伤耦合模型研究%Coupled elastoplastic-damage model for salt rock

    Institute of Scientific and Technical Information of China (English)

    房敬年; 周辉; 胡大伟; 邵建富; 梁玉雷

    2011-01-01

    岩盐力学模型是进行能源岩盐储存工程稳定性分析的基础,而损伤和塑性机制并存且相瓦耦合是岩盐力学行为的基本特点.采用云应岩盐,进行了多组围压条件下的三轴压缩试验,分析了不同围压下岩盐的变形特征.在试验分析的基础上,提出了一种能够描述岩盐特性的弹塑性损伤耦合的模型,该模型描述了岩盐损伤的演化和塑性变形的耦合关系,并引入了一种非关联的塑性流动法则来描述岩盐从塑性体积压缩到膨胀的转化.采用该模型对在三轴压缩下的岩盐应力-应变关系进行了模拟分析,并与试验数据进行了对比,结果表明该模型能够较好地描述岩盐的主要力学和变形特性.%Mechanical model is the basis for analysis of energy deposit engineering stability in salt seam; and the coupled damage and plasticity mechanism is the basic mechanical behavior of rock salt.Using rock salt from Yun-Ying, triaxial compression tests are performed under different confining pressures; and the deformation characteristics of salt rock are analyzed.Based on a brief account of experimental investigation, a coupled elastoplastic-damage model for salt rock is proposed.The model can describe the coupled relations between plastic deformation and damage evolution; and also a non-associated rule is preferred in order to describe a transition of plastic volumetric strain from compressibility to dilatancy.A simulation case is conducted to investigate the deformation processes of salt rock under triaxial compression; and the results show that the numerical simulations perfectly agree with the experimental data; so it is shown that the proposed coupled elastoplastic damage model is able to describe the main mechanical and deformation properties of salt rock.

  10. The Analysis of the Mechanical Properties of Typical Salt Rock%典型盐岩力学特性分析

    Institute of Scientific and Technical Information of China (English)

    完颜祺琪; 沈雪明; 垢艳侠; 冉莉娜

    2016-01-01

    通过单轴、三轴压缩实验及劈裂等实验研究了湖北云应、江苏淮安和河南平顶山3个地区层状盐矿岩样的短期力学特性,并对不同地区及不同深度地层的纯盐岩力学特性进行比较分析。结果表明:(1)3地区中单轴抗压强度和弹性模量最大的岩样为泥岩和含泥岩的盐岩,而其泊松比却是最小的,证明了泥岩变形性能差的特性。含有不同杂质的盐岩其抗压强度和弹性模量有所增加,其泊松比对杂质的变化不是太敏感。纯盐岩抗压强度、弹性模量和泊松比随地层深度的增加而增大,取自较浅地层的岩样单轴实验有明显的压密阶段。(2)不同地区的岩样都有随围压的增大峰值强度相应增大的规律。纯盐岩的内摩擦角基本都大于其他岩样的值,而黏聚力则都小于其他岩样的值。反映了纯盐岩晶体颗粒大,含杂质少的特点。(3)不同地区的纯盐岩相对于其他岩样的抗拉强度最小。%It is studied the short term mechanical properties of samples of bedded salt in Yunying Hubei,Huaian Jiangsu and Pingdingshan Henan by doing experiments of monopodium and triaxial compression and splitting. It also compares stratums in different district and different depth of the pure salt rock mechanical properties. The results showed that(1)the rocks in different area which have the biggest uniaxial compressive strength and modulus of elasticity and the smallest Poisson ratio belong to mudstone and mud salt rock. It indicated that mudstone has bad deformation properties. The salt rock which has different impurity will increase its compressive strength and modulus of elasticity,and its Poisson ratio is not sensitive to the change of impurity. The compressive strength,modulus of elasticity and Poisson ratio of the pure salt rock increases with increase of the depth of stratum,the rocks from the shallow layer in uniaxial tests have obvious compression

  11. The Distribution of Rock Salt and Gypsum in Sequence Stratigraphic Framework—A Case in Jialingjiang Formation in Chongqing

    Science.gov (United States)

    Caixa, Gao; Jun, Yi; Junjiang, Su; Yongqin, Zhang; Bo, Li

    2017-05-01

    The Jialingjiang Formation of the Lower Triassic in the eastern Sichuan Basin is subdivided into four members. The first and third members are featured with limestone, while the second and forth members which are clipped with gypsum and halite are characterized by dolomite and limy dolomite. At the same time, the second and forth members are the main geothermal reservoir in Chongqing area. Two sequence boundaries represented by regional unconformities and the lithology-lithofacies transition surface are recognized in the Jialingjiang formation based on outcrop and borehole data analysis. A total of two third-order sequences are subdivided in the Jialingjiang formation, and they are subcorrelated to the intervals of Member 1 to Member 2, Member 3 to Member 4, respectively. Each sequence is further subdivided into lacustrine transgresive system tract (TST) and highstand system tract (HST) according to variation in lithology and lithofacies. The sea level change is the main factor to control the sequence development. With the sea level change, the middle and late periods of HST in sequence are the favorable periods of the development of rock salt and gypsum.

  12. Attainable high capacity in Li-excess Li-Ni-Ru-O rock-salt cathode for lithium ion battery

    Science.gov (United States)

    Wang, Xingbo; Huang, Weifeng; Tao, Shi; Xie, Hui; Wu, Chuanqiang; Yu, Zhen; Su, Xiaozhi; Qi, Jiaxin; Rehman, Zia ur; Song, Li; Zhang, Guobin; Chu, Wangsheng; Wei, Shiqiang

    2017-08-01

    Peroxide structure O2n- has proven to appear after electrochemical process in many lithium-excess precious metal oxides, representing extra reversible capacity. We hereby report construction of a Li-excess rock-salt oxide Li1+xNi1/2-3x/2Ru1/2+x/2O2 electrode, with cost effective and eco-friendly 3d transition metal Ni partially substituting precious 4d transition metal Ru. It can be seen that O2n- is formed in pristine Li1.23Ni0.155Ru0.615O2, and stably exists in subsequent cycles, enabling discharge capacities to 295.3 and 198 mAh g-1 at the 1st/50th cycle, respectively. Combing ex-situ X-ray absorption near edge spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, high resolution transmission electron microscopy and electrochemical characterization, we demonstrate that the excellent electrochemical performance comes from both percolation network with disordered structure and cation/anion redox couples occurring in charge-discharge process. Li-excess and substitution of common element have been demonstrated to be a breakthrough for designing novel high performance commercial cathodes in rechargeable lithium ion battery field.

  13. Reflection of microwave from energy deposit by X-ray irradiation in rock salt: Implication of an ultra high energy salt neutrino detector to act like a radio bubble chamber

    CERN Document Server

    Chiba, Masami; Kamijo, Toshio; Nakamura, Shunsuke; Shibasaki, Yuji; Takayama, Yasuhiro; Watanabe, Yusuke; Yabuki, Fumiaki; Yasuda, Osamu; Amano, Akio; Chikashige, Yuichi; Ibe, Keisuke; Kon, Tadashi; Ninomiya, Sosuke; Shimizu, Yutaka; Takeoka, Yoshito; Taniuchi, Yasuyuki; Utsumi, Michiaki; Fujii, Masatoshi

    2007-01-01

    Existence of GZK neutrinos (ultra high energy neutrinos) have been justified although the flux is very low. A new method is desired to use a huge mass of a detector medium to detect them. A fundamental study of radar method was carried out to measure microwave reflection from electromagnetic energy deposit by X-ray irradiation in a small rock salt sample. The reflection rate of 1x10^-6 was found at the energy deposit of 1x10^19 eV which was proportional to square of the X-ray intensity suggesting the effect to be coherent scattering. The decay time of the reflection was several seconds. This effect implies a large scale natural rock salt formation could be utilized like a bubble chamber irradiated by radio wave instead of visible light to detect GZK neutrinos.

  14. Crushing leads to waste disposal savings for FUSRAP

    Energy Technology Data Exchange (ETDEWEB)

    Darby, J. [Department of Energy, Oak Ridge, TN (United States)

    1997-02-01

    In this article the author discusses the application of a rock crusher as a means of implementing cost savings in the remediation of FUSRAP sites. Transportation and offsite disposal costs are at present the biggest cost items in the remediation of FUSRAP sites. If these debris disposal problems can be handled in different manners, then remediation savings are available. Crushing can result in the ability to handle some wastes as soil disposal problems, which have different disposal regulations, thereby permitting cost savings.

  15. A new method for controlling of floor heave of deep tunnels in soft rocks by mini-tube grouting piles of crushed stones%微型碎石管注桩治理深部软岩巷道底鼓新方法

    Institute of Scientific and Technical Information of China (English)

    谢芳; 王金安

    2013-01-01

    针对造成巷道底鼓的物理和力学两种重要机制,研究并提出微型碎石管注桩治理深部软岩巷道底鼓的新方法.在物理机制方面,微型碎石桩具有渗透性极好的特点,在巷道施工和使用期间可汲取岩体中的渗水并透过碎石桩中的插管排出,从而降低软岩层因遇水膨胀导致的变形;在力学机制方面,微型碎石桩一方面通过钻孔置换出少部分底板软岩,从体量上减少变形岩体,另一方面能利用碎石桩体的侧向可压缩性耗散岩体水平变形,底板岩层中的水平地应力得以释放,极大减缓了促使底鼓变形的力学作用;通过微型碎石桩中的插管注浆加固底板岩体,提高了底板复合地基整体承载力.通过数值分析,阐明该方法在治理软岩巷道底鼓机制上的有效性.%Focusing on two important mechanisms of physics and mechanics that give rise to the floor heave of tunnels , a new method of controlling the floor heave of deep tunnels in soft rocks was proposed by means of mini-tube grouting piles of crushed stones. In physical aspect, the method utilizes the characteristics of good permeability of crushed stone pile to absorb the water in rockmass and drainage out through the tubes in the pile during the construction and application of the tunnels, resulting in the decrease in expansion deformation of soft rock due to water saturation. In mechanical aspect, partial volume in floor stratum has been replaced, on one hand, by the installed mini piles which reduce the volume of the deforming rock body, and on the other hand, amount of horizontal deformation are dissipated through the lateral compressive deformation of the crushed stone pile, and the horizontal stress is released. As a result, the mechanical affect that induces the heave deformation in floor stratum is considerably reduced. By means of grouting the crushed stones through the tube inserted in the pile, the floor stratum is reinforced and the

  16. Crushing Strength of Ship Structures

    DEFF Research Database (Denmark)

    Cerup-Simonsen, Bo; Abramowicz, W.; Høstgaard-Brene, C.N.S.

    1999-01-01

    The crushing response of ship structures is of primary importance to the designers and practicing engineers concerned with accidental loading and accident reconstruction of marine vehicles. Ship to-ship collisions, ship-harbor infrastructure interaction or ship-offshore structure interaction are ...

  17. Crushing Strength of Ship Structures

    DEFF Research Database (Denmark)

    Cerup-Simonsen, Bo; Abramowicz, W.; Høstgaard-Brene, C.N.S.

    1999-01-01

    The crushing response of ship structures is of primary importance to the designers and practicing engineers concerned with accidental loading and accident reconstruction of marine vehicles. Ship to-ship collisions, ship-harbor infrastructure interaction or ship-offshore structure interaction are ...

  18. Draft genome sequence of the extremely halophilic Halorubrum sp. SAH-A6 isolated from rock salts of the Danakil depression, Ethiopia

    OpenAIRE

    2016-01-01

    The draft genome sequence of Halorubrum sp. SAH-A6, isolated from commercial rock salts of the Danakil depression, Ethiopia. The genome comprised 3,325,770 bp, with the G + C content of 68.0%. The strain has many genes which are responsible for secondary metabolites biosynthesis, transport and catabolism as compared to other Halorubrum archaea members. Abundant genes responsible for numerous transport systems, solute accumulation, and aromatic/sulfur decomposition were detected. The first gen...

  19. Radiation damage measurements on rock salt and other minerals for waste disposal applications. Quarterly report, January 1, 1980-March 31, 1980

    Energy Technology Data Exchange (ETDEWEB)

    Swyler, K J; Loman, J M; Teutonico, L J; Elgort, G E; Levy, P W

    1980-04-10

    Different aspects of radiation damage in both synthetic NaCl crystals and various natural rock salt samples as well as granite, basalt and other minerals which will be important for radioactive waste disposal applications are being investigated. The principal means of measuring radiation damage is the determination of F-center concentrations, and the concentration and size of sodium metal colloid particles. Formation of these and other defects during irradiation and the annealing of defects and characterization of other processes occurring after irradiation are being studied as a function of dose rate, total dose, sample temperature during irradiation, strain applied prior to and during irradiation, etc. Measurements are being made on synthetic NaCl and natural rock salt samples from different geological locations, including some potential repository sites. It will be necessary to determine if radiation damage in the minerals from different localities is similar. If non-negligible differences are observed a detailed study must be made for each locality under consideration. Almost all current studies are being made on rock salt but other minerals particularly granite and basalt are being phased into the program. It is now established that radiation damage formation in both natural and synthetic rock salt is strongly dependent on strain. The strain related effects strongly indicate that the damage formation processes and in particular the colloid nucleation processes are related to the strain induced disolcations. A temporary theoretical effort has been started to determine which dislocation related effects are important for radiation damage processes and, most importantly, what dislocation interactions are most likely to create nucleation sites for colloid particles. If these preliminary studies indicate that additional theoretical studies will be useful an effort will be made to have them extended.

  20. Range sections as rock models for intensity rock scene segmentation

    CSIR Research Space (South Africa)

    Mkwelo, S

    2007-11-01

    Full Text Available This paper presents another approach to segmenting a scene of rocks on a conveyor belt for the purposes of measuring rock size. Rock size estimation instruments are used to monitor, optimize and control milling and crushing in the mining industry...

  1. Exploration and Practice of Rock Salt Brine Well Associated with Gas%卤井盐岩伴生气治理探索与实践

    Institute of Scientific and Technical Information of China (English)

    高莉霞; 刘川

    2014-01-01

    根据我公司不同时期对卤井盐岩伴生气治理的探索实践,从卤井盐岩伴生气治理的必要性出发,浅析废气处理装置在伴生有尚且不具备综合利用价值的硫化氢、天然气等可燃气体的盐岩矿山应用的可行性、运行原理及成效分析。%Based on the practice and exploration on the management of rock salt birne well associated gas by our company and starting from the necessity of the treatment of rock salt brine well associated gas, thsi paper analyzes the feasibility, operating principal and effectiveness of using waste gas treatment plant in the rock salt mine associated with hydrogen sulfide ,natural gas and other combustible gases which have no comprehensive utilization value.

  2. Experimental investigation of rock salt by uniaxial pressure test after hydrostatic preloading; Experimentelle Untersuchung des Steinsalzes mittels einaxialem Drucktest mit hydrostatischer Vorbelastung

    Energy Technology Data Exchange (ETDEWEB)

    Filimonov, Yu.L.; Shafarenko, Y.M. [Podsemgasprom GmbH, Moskau (Russian Federation). Festigkeitslab.; Lavrov, A.V.; Shkuratnik, V.L. [Moskauer Staatsbergbauuniv., Moskau (Russian Federation). Lehrstuhl fuer Physikalisch-technische Kontrolle von Bergbauprozessen

    2000-06-01

    In situ stress measurements are an important rock mechanical task in the working of rock salt deposits, in gas and mineral oil storage and in the dumping of waste in salt mines. Estimation of the stresses and the stability of the rock is necessary both for correct dimensioning of the underground cavities and also in their construction or operation. Predominantly the Hydro Frac and overdrilling methods are currently used for stress measurement. Objective restrictions, which are characteristic of these two methods, cause scientists to seek new stress measuring methods, some of which are based on other physical principles. One of the possibilities is to utilise the memory capacity of the rock and corresponding memory effects. (orig.) [German] Eine wichtige gebirgsmechanische Aufgabe beim Abbau von Steinsalzlagerstaetten, bei Gas- und Mineraloelspeicherung sowie beim Deponieren von Abfaellen im Salzgebirge stellen In-Situ-Spannungsmessungen dar. Die Einschaetzung der Spannungen und der Stabilitaet des Gebirges ist sowohl fuer richtige Dimensionierung der untertaegigen Hohlraeume als auch bei deren Bau beziehungsweise Betrieb notwendig. Zur Zeit werden fuer Spannungsmessung vorwiegend das Hydro-Frac- und das Ueberbohrverfahren verwendet. Objektive Einschraenkungen, die diesen beiden Methoden eigen sind, lassen Wissenschaftler staendig nach neuen Spannungsmessverfahren suchen, die zum Teil auf anderen physikalischen Prinzipien basieren. Eine der Moeglichkeiten besteht darin, die Gedaechtnis-Effekte auszunutzen. (orig.)

  3. Investigation on the permeability characteristics of bedded salt rocks and the tightness of natural gas caverns in such formations

    NARCIS (Netherlands)

    Liu, Wei; Muhammad, N.; Chen, Jie; Spiers, C.J.; Peach, C.J.; Deyi, Jiang; Li, Yinping

    In China, the salt formations close to the lower reaches of the large natural gas routes and the main gas consuming regions are all bedded structures. The presences of non-halite or low-halite mudstone interlayers and interfaces (salt-interlayer) in these bedded salt formations increase the concern

  4. 中国东部岩盐矿区建造盐穴储气库地质条件分析%GEOLOGICAL CONDITION ANALYSIS ON GAS STORAGE FOR BUILDING SALT CAVERN OF ROCK SALT AREA IN EASTERN CHINA

    Institute of Scientific and Technical Information of China (English)

    王少华; 杨树杰

    2015-01-01

    The halite bed of eastern China is frequentlyinterbedded with the other rocks. According to the different rock salt bed interlayer of salt bearing zone, the section structure is separated into three types including the first interlayer which is easy to build salt cavern and dominated by dissolubility salinastone-glauberite and mudstone, the second interlayer which is common to build it and dominated by clastic rock(mudstone, siltstone) with a little readily soluble salt as well as the third interlayer which is hard to build it and dominated by gypsum and anhydrite with mud and sandstone. It is easy to build salt cavern at Jintan area of Jiangsu province but hard to build it at some basins such as Wuyang city of Henan province. Some sections with thick salt bed., thin interlayer and fewwater insoluble substance are also good for build salt cavern.%中国东部岩盐层与其它岩石频繁互层.从建造储气盐穴是否有利出发,根据含盐段岩盐层夹层的不同将剖面结构类型分为三类:第1类夹层以可溶性盐类——钙芒硝及泥岩为主,该类较易建造盐穴;第2类型夹层以碎屑岩(泥岩、粉砂岩)为主,含少量易溶盐类,该类建造盐穴条件一般;第3类型夹层以石膏、硬石膏为主,含泥、砂岩,该类难以建造盐穴.在中国东部诸多盐矿区中,江苏金坛建造盐穴条件较好,易于建造盐穴.而江苏淮安、湖南衡阳、湖北潜江、河南舞阳等盆地条件较差,但在这些矿区中,选择盐层厚度相对较大,夹层较薄、水不溶物质含量较低的地段,亦可建造储气盐穴.

  5. Resarch on Unloading Modulus for Salt Rock Damage Testing%盐岩损伤测试中卸载模量研究

    Institute of Scientific and Technical Information of China (English)

    刘建锋; 徐进; 裴建良; 张茹

    2011-01-01

    利用MTS815 Flex Test GT岩石力学试验系统,对盐岩和大理岩进行了单轴压缩下的7级加卸载试验和低周循环加卸载试验测试,对盐岩和大理岩的卸载模量进行了探讨。低周循环试验加载波形采用正弦波,频率1Hz,循环应力幅值小于其平均抗压强度,单级应力幅值为30个振动循环。通过试验,得到了盐岩应力应变滞回环均为条带状,大理岩则均为尖叶状;盐岩在加卸载部位具有较大不可逆变形,对应弹性响应较慢,大理岩则反之;盐岩卸载模量变化趋势受加载测试方法影响较大,而大理岩在2种试验条件下得到的卸载模量变化趋势相似;加载应%The uniaxial seven stress levels cyclic loading and unloading test for salt rock and marble were carried out on MTS815 Flex Test GT rock mechanics test system,and the damage unloading modulus were discussed.The loading test wave for low cyclic loading test was sine wave,and its frequency was 1.0 Hz.The maximum of cyclic stress was less than the value of the average intensity of compression,and the cyclic number of every level cyclic stress was 30 cycles.The test showed that the hysteresis loop of the curve of strain and stress was the ribbon for salt rock and tine lobation for marble stone.The salt rock had larger irreversible deformation at reloading and unloading position where corresponding elastic deformation response was slow,but the results for the marble stone were contrary.Because the unloading modulus for salt rock was influenced by test method,the changing tendency of unloading modulus for salt rock during the two test methods was reverse,while the results for marble stone were consistent during the two test methods.The effect on the increment of irreversible deformation for salt rock was more prominent for the condition of the loading stress amplitude than that of the cyclic numbers.The damage variable test results revealed that it was more authentic to describe the damage

  6. Phase diagram of crushed powders

    Science.gov (United States)

    Bodard, Sébastien; Jalbaud, Olivier; Saurel, Richard; Burtschell, Yves; Lapebie, Emmanuel

    2016-12-01

    Compression of monodisperse powder samples in quasistatic conditions is addressed in a pressure range such that particles fragmentation occurs while the solid remains incompressible (typical pressure range of 1-300 MPa for glass powders). For a granular bed made of particles of given size, the existence of three stages is observed during compression and crush up. First, classical compression occurs and the pressure of the granular bed increases along a characteristic curve as the volume decreases. Then, a critical pressure is reached for which fragmentation begins. During the fragmentation process, the granular pressure stays constant in a given volume range. At the end of this second stage, 20%-50% of initial grains are reduced to finer particles, depending on the initial size. Then the compression undergoes the third stage and the pressure increases along another characteristic curve, in the absence of extra fragmentation. The present paper analyses the analogies between the phase transition in liquid-vapour systems and powder compression with crush-up. Fragmentation diagram for a soda lime glass is determined by experimental means. The analogues of the saturation pressure and latent heat of phase change are determined. Two thermodynamic models are then examined to represent the crush-up diagram. The first one uses piecewise functions while the second one is of van der Waals type. Both equations of state relate granular pressure, solid volume fraction, and initial particle diameter. The piecewise functions approach provides reasonable representations of the phase diagram while the van der Waals one fails.

  7. Failure probability analysis of coal crushing induced by uncertainty of influential parameters under condition of in-situ reservoir

    Institute of Scientific and Technical Information of China (English)

    张立松; 闫相祯; 杨秀娟; 田中兰; 杨恒林

    2014-01-01

    The uncertainties of some key influence factors on coal crushing, such as rock strength, pore pressure and magnitude and orientation of three principal stresses, can lead to the uncertainty of coal crushing and make it very difficult to predict coal crushing under the condition of in-situ reservoir. To account for the uncertainty involved in coal crushing, a deterministic prediction model of coal crushing under the condition of in-situ reservoir was established based on Hoek-Brown criterion. Through this model, key influence factors on coal crushing were selected as random variables and the corresponding probability density functions were determined by combining experiment data and Latin Hypercube method. Then, to analyze the uncertainty of coal crushing, the first- order second-moment method and the presented model were combined to address the failure probability involved in coal crushing analysis. Using the presented method, the failure probabilities of coal crushing were analyzed for WS5-5 well in Ningwu basin, China, and the relations between failure probability and the influence factors were furthermore discussed. The results show that the failure probabilities of WS5-5 CBM well vary from 0.6 to 1.0; moreover, for the coal seam section at depth of 784.3-785 m, the failure probabilities are equal to 1, which fit well with experiment results; the failure probability of coal crushing presents nonlinear growth relationships with the increase of principal stress difference and the decrease of uniaxial compressive strength.

  8. An Experimental Research of Biomass Crushing System

    Science.gov (United States)

    Xia, Yue

    2017-05-01

    Biomass crushing is precondition for utilization and transformation of biomass energy. Compressive strength of biomass raw materials is generally small with long fiber, and multiple crushing methods like shocking, shearing and grinding should be used to realize high-efficiency crushing. Based on this, this paper researched and developed a set of biomass fine crushing system, and conducted an optimized study of main parameters influencing crushing process—revolving speed, between blade and cutter head and material moisture content. Results indicated that this set of crushing system could complete fine crushing of biomass, particle size of crushed products was controlled below 250µm, crushing energy consumption was between 70—120kwh/t, both of which were mainly decided by material moisture content and operating parameters of crusher. Revolving speed of crusher was elevated, proportion of particles (d<106µm) with fine particle size in crushed products increased, and unit energy consumption of crushing increased; narrowing space between blade and cutter head could improve crushing effect of biomass, but unit energy consumption increased; the higher the moisture content was, the less the content of fine particles in crushed products would be, and the greater unit energy consumption would be. By comprehensive comparison, the optimal operating conditions for crushing were: revolving speed was 3600r/min, space between impulse blade and cutter head was 8mm, moisture content was 10.6%, energy consumption was 98kwh/t, product particle size distribution was: those with particle size below 106µm occupied 71.5% and those between 106µm—250µm occupied 28.5%.

  9. 含杂质盐岩力学特性对比试验研究%Experimental study on mechanical property of rock salt with impurity

    Institute of Scientific and Technical Information of China (English)

    郑雅丽; 张华宾; 王芝银; 丁双龙; 王芝银

    2012-01-01

    Mechanical experiments were carried out on the different kinds of rock samples which are salt,mudstone,glauberite,anhydrite and salt-mudstone.The experiment results indicate that different impurities have obvious effect on the deformability and the compressive strength;The modulus of elasticity and the uniaxial strength have a large range with the kind and content of the impurities and the glauberite's are higher;In triaxial compression tests,pure rock salts have a higher internal friction angle and a lower cohesion than the rocks with impurities.Besides the rock salt,the internal friction angle and cohesion of anhydrite are lower than others'.The test results provide certain reference to the design of salt cavern under complex stratum.%从某地拟建地下盐穴储库库区取芯,对含不同杂质盐岩(纯盐岩、钙芒硝质盐岩、硬石膏质盐岩及泥质混合盐岩)进行了力学试验,并对所获得的力学特性进行了对比分析。结果表明:①在单轴和三轴压缩试验过程中,不同杂质成分对抑制盐岩的变形能力、提高盐岩抗压强度的作用有所不同;②含不同杂质盐岩的弹性模量、单轴抗压及抗拉强度有较大变化区间,钙芒硝质盐岩的弹性模量和抗拉强度较大;③通过三轴压缩试验获得含不同杂质盐岩内摩擦角的量值明显低于纯盐岩,而黏聚力均大于纯盐岩。除纯盐岩外,硬石膏质盐岩的内摩擦角和黏聚力相对较小。

  10. Modelling of the reactive transport for rock salt-brine in geological repository systems based on improved thermodynamic database (Invited)

    Science.gov (United States)

    Müller, W.; Alkan, H.; Xie, M.; Moog, H.; Sonnenthal, E. L.

    2009-12-01

    for both Pitzer ion-interaction parameters and thermodynamic equilibrium constants. The reliability of the parameters is as important as the accuracy of the modelling tool. For this purpose the project THEREDA (www.thereda.de)was set up. The project aims at a comprehensive and internally consistent thermodynamic reference database for geochemical modelling of near and far-field processes occurring in repositories for radioactive wastes in various host rock formations. In the framework of the project all data necessary to perform thermodynamic equilibrium calculations for elevated temperature in the system of oceanic salts are under revision, and it is expected that related data will be available for download by 2010-03. In this paper the geochemical issues that can play an essential role for the transport of radioactive contaminants within and around waste repositories are discussed. Some generic calculations are given to illustrate the geochemical interactions and their probable effects on the transport properties around HLW emplacements and on CO2 generating and/or containing repository systems.

  11. EXPERIMENTAL INVESTIGATION ON MESO-PORE STRUCTURE PROPERTIES OF BEDDED SALT ROCK%层状盐岩细观孔隙特性试验研究

    Institute of Scientific and Technical Information of China (English)

    纪文栋; 杨春和; 刘伟; 李铭铭

    2013-01-01

    孔隙特性是决定盐岩储库密闭性的关键因素。对层状盐岩中不同岩性的试样开展压汞法测试和电镜扫描试验,分析层状盐岩孔隙率与渗透率的关系,并对层状盐岩的孔隙结构、分布特性及其密封性能进行研究。压汞测试表明:盐岩、泥岩和泥质钙芒硝的孔隙率平均值分别为2.7%,6.0%和2.5%,与常规岩石对比发现层状盐岩的孔隙率处在非常低的水平。孔隙率与渗透率之间存在明显的关系:低孔隙率是低渗透率的充分非必要条件,而高渗透率是高孔隙率的充分非必要条件,高孔隙率的试样有时也会出现低渗透率的情况。对岩体渗透率影响最大的是相互连通的部分孔隙,一旦存在连通的孔隙,渗透率就会显著增加。电镜扫描结果显示,盐岩是典型的晶体构造,内部结构密实,无明显的孔隙存在。泥岩中黏土和有机质颗粒的差异会显著影响其孔隙性质,颗粒粒径大小不一且呈块状或卵石状的区域孔隙大量发育,颗粒均质、呈块状的区域结构密实,孔隙较不发育。泥岩和盐岩的交界面处并不是孔隙发育的区域,泥岩和盐岩相互咬合、嵌入及泥岩细小颗粒的填充使孔隙率降低。含泥盐岩(含盐泥岩)中局部孔隙较为发育,并且连通度较高,是渗流可能发生的区域,建议储气库设计建造时避免将关键部位设置在孔隙发育区域,以保障密闭性。本文的研究成果可为储气库的建造及密闭性分析提供指导。%The property of pore structure is the key issue for the tightness of storage caverns. Mercury injection porosimetry tests and scanning electron microscopy(SEM) tests are conducted for different lithological rocks in bedded salt rock. The relationship between porosity and permeability,pore structure,distribution characteristics, as well as the corresponding tightness properties,are analyzed. The mercury injection

  12. Half-metallicity, magnetism and electrical resistivity of Sn{sub 1−x}Mn{sub x}Te alloys in rock salt and zinc blende structures

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yong [State Key Laboratory of Metastable Materials Science and Technology and College of Science, Yanshan University, Qinhuangdao 066004 (China); Physics Department, Brock University, St. Catharines, Ontario, Canada L2S 3A1 (Canada); Bose, S.K., E-mail: sbose@brocku.ca [Physics Department, Brock University, St. Catharines, Ontario, Canada L2S 3A1 (Canada); Kudrnovský, J. [Institute of Physics, Academy of the Sciences of the Czech Republic, Na Slovance 2, 182 21 Prague 8 (Czech Republic)

    2015-02-01

    This work presents the results for the magnetic properties of the compound SnTe doped with 3d transition metal Mn from the viewpoint of potential application in spintronics. We report a systematic density-functional study of the electronic structure and magnetic properties of these ternary compounds in both rock salt and zinc blende structures. In both cases, it is the Sn-sublattice that is doped with Mn. Among the various compounds studied, we identify one as a possible half-metallic candidate: 25% Mn-doping of the Sn-sublattice in the rock salt structure. Others are either magnetic semiconductors or metals. Exchange interaction between the Mn atoms is discussed and results for resistivities for various compositions in the two structures are compared. For low Mn concentration, the zero temperature ground state of the compound is found to be semiconducting and the Mn–Mn exchange interactions are dominantly antiferromagnetic. The weakly ferromagnetic interaction and ordering found in experiments is shown to be ‘carrier induced’. It is shown that ferromagnetic interactions between the Mn atoms are caused by the presence of ‘holes’. Another likely cause is the presence of extra Te atoms in interstitial locations, which seems to suppress Mn–Mn antiferromagnetic interactions. This is supported by the earlier experimental observation that a weak ferromagnetism occurs in these alloys for low Mn concentration only if the samples are subjected to additional Te-flux. - Highlights: • We study electronic structure and magnetic properties of Mn-doped semiconductor SnTe. • We find one antiferromagnetic half-metallic case: Sn{sub 3}Mn{sub 1}Te{sub 4} in rock salt structure. • We show that the presence of ‘holes’ may turn antiferromagnetic Mn–Mn interactions to ferromagnetic. • Results are compared with available experimental data.

  13. Comment on "Thermodynamic properties of rock-salt ZnO" by Leitner et al. [Thermochimica Acta 572 (2013) 1-5

    OpenAIRE

    2013-01-01

    Very recently Leitner et al. [Thermochimica Acta 572 (2013) 1-5] have tried to extract the thermodynamic data of rock-salt ZnO from ab initio and experimental data available in the literature. In this Comment we show that neglecting (i) the strongly pronounced kinetic features of the pressure-induced phase transition in ZnO at room temperature and (ii) results of calorimetric measurements available in the literature [Russ. Chem. Bull. 59 (2010) 325-328] makes the proposed set of thermodynamic...

  14. Preliminary Analysis of Engineering Effect of Crushed Rocks Mat Embankment in Heimahe Section of Qinghai-Tibet Highway%青藏公路黑马河试验段碎石垫层路基工程效果初步分析

    Institute of Scientific and Technical Information of China (English)

    李东庆; 常法; 张坤; 房建宏; 徐安花

    2011-01-01

    基于青藏公路黑马河试验段碎石垫层路基近1 a的温度、水分监测资料,初步分析了碎石垫层路基温度,水分的发展与分布特征以及造成这些差异的原因,并与传统的砂砾垫层比较.结果表明:碎石垫层加隔水土工布能够更好的削弱毛细水自下而上的迁移,起到了一定的隔水排水效果,对于防治季节性冻土路基冻胀病害具有积极作用.%Based on the monitoring data of moisture and temperature along the National Road 109 in Qinghai Province,the changes and induced causes of temperatures and moistures at different positions of an embankment under the action of external climate conditions were systematically analyzed.The change rates and induced causes of moistures for the traditional gravel embankment and the crushed rock mat embankment with waterproof geotextile were discussed.Further more,the effects of these differences on the frost heaving of embankment were also analyzed.It is found that the rushed rock mat embankment with waterproof geotextile is better than the traditional gravel embankment for preventing frost heaving and boiling of embankment in seasonally frozen soil regions,even that there are top-down migration of ground surface water,and soil moisture migration under winter negative temperature gradient and capillary action from the bottom to promote the migration of the soil water.

  15. Quality control chart for crushed granite concrete

    Directory of Open Access Journals (Sweden)

    Ewa E. DESMOND

    2016-07-01

    Full Text Available A chart for assessing in-situ grade (strength of concrete, has been developed in this study. Four grades of concrete after the Nigerian General Specification for Roads and bridges (NGSRB-C20, C25, C30 and C35, is studied at different water-cement ratios for medium and high slump range. The concrete mixes are made from crushed granite rock as coarse aggregate with river sand as fine aggregate. Compression test on specimens are conducted at curing age of 1, 3, 7, 14, 21, 28 and 56 days. Results on concrete workability from slump values, and water-cement ratios revealed that specimens with lower water-cement ratio were less workable but had higher strength, compared to mixes with higher water cement ratio. A simple algorithm using nonlinear regression analysis performed on each experimental data set produced Strength-Age (S-A curves which were used to establish a quality control chart. The accuracy of these curves were evaluated by computing average absolute error (AAS, the error of estimate (EoE and the average absolute error of estimate (Abs EoE for each concrete mix. These were done based on the actual average experimental strengths to measure how close the predicted values are to the experimental data set. The absolute average error of estimate (Abs. EoE recorded was less than ±10% tolerance zone for concrete works.

  16. Rock-avalanche dynamics revealed by large-scale field mapping and seismic signals at a highly mobile avalanche in the West Salt Creek valley, western Colorado

    Science.gov (United States)

    Coe, Jeffrey A.; Baum, Rex L.; Allstadt, Kate; Kochevar, Bernard; Schmitt, Robert G.; Morgan, Matthew L.; White, Jonathan L.; Stratton, Benjamin T.; Hayashi, Timothy A.; Kean, Jason W.

    2016-01-01

    On 25 May 2014, a rain-on-snow–induced rock avalanche occurred in the West Salt Creek valley on the northern flank of Grand Mesa in western Colorado (United States). The avalanche mobilized from a preexisting rock slide in the Green River Formation and traveled 4.6 km down the confined valley, killing three people. The avalanche was rare for the contiguous United States because of its large size (54.5 Mm3) and high mobility (height/length = 0.14). To understand the avalanche failure sequence, mechanisms, and mobility, we conducted a forensic analysis using large-scale (1:1000) structural mapping and seismic data. We used high-resolution, unmanned aircraft system imagery as a base for field mapping, and analyzed seismic data from 22 broadband stations (distances avalanche exerted on the earth and tracked these forces using curves in the avalanche path. Our results revealed that the rock avalanche was a cascade of landslide events, rather than a single massive failure. The sequence began with an early morning landslide/debris flow that started ∼10 h before the main avalanche. The main avalanche lasted ∼3.5 min and traveled at average velocities ranging from 15 to 36 m/s. For at least two hours after the avalanche ceased movement, a central, hummock-rich core continued to move slowly. Since 25 May 2014, numerous shallow landslides, rock slides, and rock falls have created new structures and modified avalanche topography. Mobility of the main avalanche and central core was likely enhanced by valley floor material that liquefied from undrained loading by the overriding avalanche. Although the base was likely at least partially liquefied, our mapping indicates that the overriding avalanche internally deformed predominantly by sliding along discrete shear surfaces in material that was nearly dry and had substantial frictional strength. These results indicate that the West Salt Creek avalanche, and probably other long-traveled avalanches, could be modeled as two

  17. 多年冻土区宽幅公路路基降温效果研究——一种L型热管-块碎石护坡复合路基%Cooling effect of combined L-shaped thermosyphon, crushed-rock revetment and insulation for high-grade highways in permafrost regions

    Institute of Scientific and Technical Information of China (English)

    董元宏; 赖远明; 陈武

    2012-01-01

    In order to keep the thermal stability of large-width highway embankment in permafrost regions, a new type of cooling measure of combined L-shaped thermosyphon, crushed-rock revetment and insulation is presented. To examine its cooling effect, laboratory tests are carried out. The test results have preliminarily proved the effectiveness of the new cooling measure. To further validate its effectiveness in the service life of the highways in permafrost regions, based on relative theories and the laboratory test results, a numerical model for the highway embankment is established, and the temperature characteristics of the embankment in its service life are analyzed. The numerical results show that the combination of the L-shaped thermosyphon, crushed-rock revetment and insulation is effective to keep the thermal stability of the large-width embankment in its service life under the condition that the air temperature is warmed up by 2.6℃. Based on this, the new combined cooling measure is suggested to be used in the construction of large-width embankment in permafrost regions.%为维护多年冻土区宽幅高等级公路的热稳定性及保护下伏冻土,提出了一种L型热管一块碎石护坡保温板复合路基。为研究这种新型路基的降温效果,进行了室内模型试验,试验结果初步证明了这种路基的有效降温能力。为研究这种新型路基的长期效果,采用相关理论,结合室内模型试验的结果,依据青藏高原多年冻土区宽幅高等级公路的气温和地质条件,利用数值方法对有无L型热管的块碎石护坡保温板复合路基的温度特征进行了分析和比较。结果表明:在年平均气温为-4.0℃的青藏高原多年冻土区,考虑未来50a气温上升2.6℃的条件下,新的复合路基能够从整体上有效降低路基下土体的温度,确保高温多年冻土区宽幅高等级公路路基的热稳定性。

  18. Aluminum Honeycomb Characteristics in Dynamic Crush Environments

    Energy Technology Data Exchange (ETDEWEB)

    Bateman, Vesta I.; Swanson, Lloyd H.

    1999-07-01

    Fifteen aluminum honeycomb cubes (3 in.) have been crushed in the Mechanical Shock Laboratory's drop table testing machines. This report summarizes shock experiments with honeycomb densities of 22.1 pcf and 38.0 pcf and with crush weights of 45 lb, 168 lb, and 268 lb. The honeycomb samples were crushed in all three orientations, W, L, and T. Most of the experiments were conducted at an impact velocity of {approx}40 fps, but higher velocities of up to 90 fps were used for selected experiments. Where possible, multiple experiments were conducted for a specific orientation and density of the honeycomb samples. All results are for Hexcel honeycomb except for one experiment with Alcore honeycomb and have been evaluated for validity. This report contains the raw acceleration data measured on the top of the drop table carriage, pictures of the crushed samples, and normalized force-displacement curves for all fifteen experiments. These data are not strictly valid for material characteristics in L and T orientations because the cross-sectional area of the honeycomb changed (split) during the crush. However, these are the best data available at this time. These dynamic crush data do suggest a significant increase in crush strength to 8000 psi ({approximately} 25-30% increase) over quasi-static values of {approximately}6000 psi for the 38.0 pcf Hexcel Honeycomb in the T-orientation. An uncertainty analysis is included and estimates the error in these data.

  19. Density functional study of the optical response of FeN and CoN nitrides with zinc-blend and rock-salt structures

    Science.gov (United States)

    Cheballah, Y.; Ziane, A.; Bouarab, S.; Vega, A.

    2017-01-01

    We investigated the optical properties of iron and cobalt mono-nitrides in rock-salt and zinc-blende crystal structures. Density functional theoretic calculations were performed using the linear muffin tin orbital method in the generalized gradient approximation for exchange and correlation. The optical response was characterized by means of the dielectric function, calculated for each structural phase in the different magnetic arrangements found experimentally and theoretically. The origin of the main absorption peaks was traced back to particular interband transitions after a careful analysis of the band structures and orbital- and atom- projected electronic densities of states. The optical response of both nitrides with this structure in the nomagnetic state is very similar at photon frequencies below 2 eV, but differ at high frequencies. In zinc-blende structure, both compounds are nomagnetic and present an optical gap of about 0.5 eV for interband transitions in their optical response.

  20. Draft genome sequence of the extremely halophilic Halorubrum sp. SAH-A6 isolated from rock salts of the Danakil depression, Ethiopia

    Directory of Open Access Journals (Sweden)

    Ashagrie Gibtan

    2016-12-01

    Full Text Available The draft genome sequence of Halorubrum sp. SAH-A6, isolated from commercial rock salts of the Danakil depression, Ethiopia. The genome comprised 3,325,770 bp, with the G + C content of 68.0%. The strain has many genes which are responsible for secondary metabolites biosynthesis, transport and catabolism as compared to other Halorubrum archaea members. Abundant genes responsible for numerous transport systems, solute accumulation, and aromatic/sulfur decomposition were detected. The first genomic analysis encourages further research on comparative genomics, and biotechnological applications. The NCBI accession number for this genome is SAMN04278861 and ID: 4278861 and strain deposited with accession number KCTC 43215.

  1. Draft genome sequence of the extremely halophilic Halorubrum sp. SAH-A6 isolated from rock salts of the Danakil depression, Ethiopia.

    Science.gov (United States)

    Gibtan, Ashagrie; Woo, Mingyeong; Oh, Dokyung; Park, Kyounghee; Lee, Han-Seung; Sohn, Jae Hak; Lee, Dong-Woo; Shin, Jung-Kue; Lee, Sang-Jae

    2016-12-01

    The draft genome sequence of Halorubrum sp. SAH-A6, isolated from commercial rock salts of the Danakil depression, Ethiopia. The genome comprised 3,325,770 bp, with the G + C content of 68.0%. The strain has many genes which are responsible for secondary metabolites biosynthesis, transport and catabolism as compared to other Halorubrum archaea members. Abundant genes responsible for numerous transport systems, solute accumulation, and aromatic/sulfur decomposition were detected. The first genomic analysis encourages further research on comparative genomics, and biotechnological applications. The NCBI accession number for this genome is SAMN04278861 and ID: 4278861 and strain deposited with accession number KCTC 43215.

  2. Creep acoustic emission of rock salt under triaxial compression%岩盐三轴蠕变声发射特征研究

    Institute of Scientific and Technical Information of China (English)

    吴池; 刘建锋; 周志威; 卓越

    2016-01-01

    To study and analyze the acoustic emission activity characteristics in the first and stable phases of salt creep, a series of triaxial creep compression tests are carried out using MTS815 flex test GT rock mechanics test system and PCI-2 acoustic emission (AE) monitoring system. The results show: under the triaxial condition, the characteristic parameters of AE such as ringing count rate and energy are proportional to the creep rate. The curve tendency of AE characteristic parameters and creep rate are basically the same. Under the constant confining pressure, the higher axial stress can accelerate the creep rate, and the AE activities also increase, which are characterized by the increase of AE incident points, ringing count rate, energy, cumulative ringing count and cumulative energy. At the same time, through the reduction of points of AE events point, it provides a basis for the study on the long-term time strength and creep damage evolution of salt rock. The creep fractal dimension values of AE of rock salt in various periods are calculated using the G–P algorithm. The laws of rise-fall-fluctuation are summarized. It may that provide the basis for studying the stability of the internal damage of rock salt.%利用四川大学 MTS815电液伺服岩石试验系统和 PCI–2声发射监测仪对岩盐进行蠕变加载试验,根据试验数据分析了岩盐蠕变前两个阶段的声发射活动特征。试验结果表明,三轴条件下,声发射特征参数,振铃计数率、能量均与蠕变速率成正比;声发射特征参数累积变化曲线与蠕变曲线走势基本相同。围压不变的情况下,较高的轴向应力能够加快试样的蠕变速率,声发射活动也有所增强,表现为 AE 定位点增多、振铃计数率和能量增大,以及累积振铃计数和累积能量的增加。通过对声发射事件点进行还原,为研究岩盐蠕变长期强度以及损伤演化提供了依据。利用 G–P算法,计算

  3. Shaft sealing concepts for high-level radioactive waste repositories based on the host-rock options rock salt and clay stone; Schachtverschlusskonzepte fuer zukuenftige Endlager fuer hochradioaktive Abfaelle fuer die Wirtsgesteinsoptionen Steinsalz und Ton

    Energy Technology Data Exchange (ETDEWEB)

    Kudla, Wolfram; Gruner, Matthias [TU Bergakademie Freiberg (Germany). Inst. fuer Erdbau und Spezialtiefbau; Herold, Philipp; Jobmann, Michael [DBE Technology GmbH, Peine (Germany)

    2015-07-01

    Unlike the shaft barriers used for the dry preservation of former mine workings and underground storage sites, shaft seals designed for radioactive-waste repositories must also fulfil additional requirements associated with the design diversity of the sealing system. This diversity makes use of the simple redundancy principle in order to prevent the proliferation of defects. In practice this means combining several sealing elements made from different materials or from materials with different properties. The R and D project, Shaft sealing systems for final repositories for high-level radioactive waste (ELSA) - phase 2: concept design for shaft seals and testing of the functional elements of shaft seals', which was funded by the Federal Ministry for Economic Affairs and Energy (BMWi), set out to investigate potential sealing elements for the two host-rock options rock salt and mudstone. This paper combines the text that the authors presented at the First International Freiberg Shaft Colloquium held at the Freiberg University of Mining and Technology on 01.10.2014 with a presentation on the sealing elements that were investigated as part of the R and D project.

  4. Spin-polarized investigation of ferromagnetism on magnetic semiconductors Mn{sub x}Ca{sub 1−x}S in the rock-salt phase

    Energy Technology Data Exchange (ETDEWEB)

    Choutri, H.; Ghebouli, M.A. [LMSE Laboratory, University of Bachir Ibrahimi, 34265 Bordj-Bou-Arréridj (Algeria); Ghebouli, B. [Laboratory of Surface and Interface Studies of Solid Materials, Department of Physics, Faculty of Science, Setif University 1, Setif 19000 (Algeria); Bouarissa, N., E-mail: n_bouarissa@yahoo.fr [Department of Physics, Faculty of Science, University of M' sila, 28000 M' sila (Algeria); Uçgun, E.; Ocak, H.Y. [Department of Physics, Faculty of Arts and Sciences, Dumlupinar University, Kutahya (Turkey)

    2014-12-15

    The structural, elastic, electronic and magnetic properties of the diluted magnetic semiconductors Mn{sub x}Ca{sub 1−x}S in the rock-salt phase have been investigated using first-principles calculations with both LDA and LDA + U functional. Features such as lattice constant, bulk modulus, elastic constants, spin-polarized band structure, total and local densities of states have been computed. We predict the values of the exchange constants and the band edge spin splitting of the valence and conduction bands. The hybridization between S-3p and Mn-3d produces small local magnetic moment on the nonmagnetic Ca and S sites. The ferromagnetism is induced due to the exchange splitting of S-3p and Mn-3d hybridized bands. The total magnetic moment per Mn of Mn{sub x}Ca{sub 1−x}S is 4.4μ{sub B} and 4.5μ{sub B} for LDA and LDA + U functional and is independent of the Mn concentration. The unfilled Mn-3d levels reduce the local magnetic moment of Mn from its free space charge value of 5μ{sub B}–4.4μ{sub B} and4.5μ{sub B} for LDA and LDA + U functional due to 3p–3d hybridization. - Highlights: • Fundamental properties of magnetic semiconductors Mn{sub x}Ca{sub 1−x}S. • Rock-salt phase of Mn{sub x}Ca{sub 1−x}S. • Magnetic properties of the diluted magnetic semiconductors Mn{sub x}Ca{sub 1−x}S. • The use of LDA + U functionals.

  5. On the progressive nature of grain crushing

    Directory of Open Access Journals (Sweden)

    Ciantia Matteo O.

    2017-01-01

    Full Text Available In this work acoustic emission (AE is used as experimental evidence of the progressive nature of grain crushing. Stress controlled high pressure oedometric compression test are carried out on 1.2 mm monodisperse samples of glass beads. It was observed that the granular assembly starts to experience particle breakage at a vertical stress of about 25MPa. When this yield pressure is exceeded the glass beads start to break emitting loud impulsive sound and the vertical displacement increases rapidly. The load was increased beyond the yield stress and at each increment while the vertical stress remained constant the sample continued to emit sound. The emission of sound at a constant vertical stress indicates that crushing is a progressive failure mechanism; once the first crushing event occurs, the structure starts to rearrange causing other crushing events to occur and additional settlement. In particular, two signal processing algorithms are used on the samples of the acoustic signal to obtain two additional metrics of the crushing evolution. The first is the cumulative energy versus time. The second is the number of crushing events versus time, which is based on the automatic detection of the peaks of the sound signal envelope. There is a clear correlation between the cumulative acoustic energy emitted and the observed sample displacement. Using laser scanning, the evolution of the particle size distribution and particle shape are measured in detail so that a link between the acoustic data and the crushing intensity is established. The crushing intensity was controlled using materials with different strengths.

  6. environmental impact of aggregate mining by crush rock industries ...

    African Journals Online (AJOL)

    2012-07-02

    Jul 2, 2012 ... method concerned with the extraction of non-fuel and non-metal minerals from .... pacity, problems in human relations, and a number of ... sons [19], sleep disturbance on the other hand is con- ..... season. This is expected as the dominant wind system .... Chrysanthus, C. Evaluating Baseline Data for Trace.

  7. Geochemical characterization of fluoride in water, table salt, active sediment, rock and soil samples, and its possible relationship with the prevalence of enamel fluorosis in children in four municipalities of the department of Huila (Colombia).

    Science.gov (United States)

    Martignon, Stefania; Opazo-Gutiérrez, Mario Omar; Velásquez-Riaño, Möritz; Orjuela-Osorio, Iván Rodrigo; Avila, Viviana; Martinez-Mier, Esperanza Angeles; González-Carrera, María Clara; Ruiz-Carrizosa, Jaime Alberto; Silva-Hermida, Blanca Cecilia

    2017-06-01

    Fluoride is an element that affects teeth and bone formation in animals and humans. Though the use of systemic fluoride is an evidence-based caries preventive measure, excessive ingestion can impair tooth development, mainly the mineralization of tooth enamel, leading to a condition known as enamel fluorosis. In this study, we investigated the geochemical characterization of fluoride in water, table salt, active sediment, rock and soil samples in four endemic enamel fluorosis sentinel municipalities of the department of Huila, Colombia (Pitalito, Altamira, El Agrado and Rivera), and its possible relationship with the prevalence of enamel fluorosis in children. The concentration of fluoride in drinking water, table salt, active sediment, rock, and soil was evaluated by means of an ion selective electrode and the geochemical analyses were performed using X-ray fluorescence. Geochemical analysis revealed fluoride concentrations under 15 mg/kg in active sediment, rock and soil samples, not indicative of a significant delivery to the watersheds studied. The concentration of fluoride in table salt was found to be under the inferior limit (less than 180 μg/g) established by the Colombian regulations. Likewise, exposure doses for fluoride water intake did not exceed the recommended total dose for all ages from 6 months. Although the evidence does not point out at rocks, soils, fluoride-bearing minerals, fluoridated salt and water, the hypothesis of these elements as responsible of the current prevalence of enamel fluorosis cannot be discarded since, aqueducts might have undergone significant changes overtime.

  8. Development of the loosening zone around ultimate storage cavities in rock salt and its treatment in safety analyses; Entwicklung der Auflockerungszone um Endlagerhohlraeume im Steinsalz und ihre Behandlung in Sicherheitsanalysen. Neuere Ergebnisse eines EU-Projekts

    Energy Technology Data Exchange (ETDEWEB)

    Wieczorek, Klaus [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) mbH, Braunschweig (Germany). Abt. Prozessanalyse; Foerster, Bernd [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) mbH, Braunschweig (Germany). Abt. Sicherheitsanalysen; Rothfuchs, Tilmann [Gesellschaft fuer Anlagen- und Reaktorsicherheit mbH (GRS), Braunschweig (Germany). Bereich Endlagersicherheitsforschung

    2011-05-15

    Excavation Damaged Zones (EDZ) in rock salt evolve as a result of the mechanical response of the rock to the excavation of underground openings. In the region close to the opening the dilatancy boundary will be exceeded, leading to microfracturing and an associated increase of porosity and permeability of the salt rock. EDZ evolution is especially relevant when considering the effectiveness of sealing structures in a nuclear waste repository. The focus of the salt group in the European Community project THERESA has been on modeling of rock salt dilatancy and on recompaction or healing effects. Laboratory experiments with different objectives were performed to produce data for model calibration. A benchmark simulation of a laboratory test case was defined and performed using the calibrated models. Finally, one of the models was used to predict EDZ evolution and recompaction around a sealed drift and the results were used as input for the analysis with the Total System Performance Analysis (TSPA) code module LOPOS. In the frame of this study, a time-dependent EDZ permeability was implemented in a TSPA code for the first time. (orig.)

  9. 盐岩蠕变模型的建立及其在地下天然气储气库中的应用%Rock Salt Creep Model Of Underground Gas Storage And Its Application

    Institute of Scientific and Technical Information of China (English)

    迟明

    2011-01-01

    Based on uniaxial creep test of the underground gas storage surrounding rock salt,the creep characteristics of rock salt was analyzed,and builds rock salt creep model.Through the least-square principle regression obtained each parameter of the creep model.By using the model the stability of underground natural gas storage was simulated,results indicate that the model can well reflect the creep regularity and gypsum can be used to predict the long-term stability of the rock salt natural gas storage.%本文以地下储气库盐岩单轴蠕变试验为例,对盐岩的蠕变特性进行了分析,建立了盐岩的蠕变模型;通过最小二乘法原理回归得出了盐岩蠕变模型中的各个参数。利用该模型对地下天然气储气库进行了数值计算分析,结果表明模型可以很好的反映盐岩的蠕变规律且可用来预测盐岩天然气储气库的长期稳定性。

  10. Characterizing large strain crush response of redwood

    Energy Technology Data Exchange (ETDEWEB)

    Cramer, S.M.; Hermanson, J.C. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Civil and Environmental Engineering; McMurtry, W.M. [Sandia National Labs., Albuquerque, NM (United States)

    1996-12-01

    Containers for the transportation of hazardous and radioactive materials incorporate redwood in impact limiters. Redwood is an excellent energy absorber, but only the most rudimentary information exists on its crush properties. The objectives of the study were to fill the information gap by collecting triaxial load-deformation data for redwood; to use these data to characterize redwood crush, assess current wood failure theories, provide developments toward a complete stress-strain theory for redwood; and to review the literature on strain-rate effects on redwood crush performance. The load-deformation responses of redwood at temperature conditions corresponding to ambient (70{degrees}F), 150{degrees}F, and {minus}20{degrees}F conditions were measured in approximately 100 confined compression tests for crush levels leading to material densification. Data analysis provided a more complete description of redwood crush performance and a basis for assessing proposed general orthotropic stress-strain relationships for redwood. A review of existing literature indicated that strain-rate effects cause at most a 20 percent increase in crush stress parallel to grain.

  11. Crushed aggregates for roads and their properties for frost protection

    Science.gov (United States)

    Kuznetsova, Elena; Willy Danielsen, Svein

    2015-04-01

    Crushed aggregates for roads and their properties for frost protection Elena Kuznetsova, NTNU and Svein Willy Danielsen, SINTEF With natural (fluvial, glaciofluvial) sand/gravel resources being rapidly depleted in many countries, the last decade has seen a significant trend towards using more alternative materials for construction purpose. In Norway the development and implementation of crushed aggregate technology has been the most important way to get around the problem with increased resource scarcity. Today Norway is one the European countries with the highest percentage of crushed/manufactured aggregates. A crushed product will reveal a different particle size distribution, a sharper, more angular particle shape, and not least - a significantly different mineral composition. The latter may often be characterised by more polymineral composition, and it will also much more depend on the local bedrock. When handled with care and knowledge, these differences can give the user a lot of new opportunities relating to materials design. Norwegian road construction practice has changed significantly during the last 40 years due to the replacement of gravel by crushed rock materials in the granular layers of the pavements. The use of non-processed rock materials from blasting was allowed in the subbase layer until 2012. This was a reason for a lot of problems with frost heaving due to inhomogeneity of this material, and in practice it was difficult to control the size of large stones. Since 2012 there is a requirement that rock materials for use in the subbase layer shall be crushed (Handbook N200, 2014). During the spring 2014 The Norwegian Public Roads Administration introduced a new handbook with requirements for roads construction in Norway, including new specifications for the frost protection layer. When pavements are constructed over moist and/or frost susceptible soils in cold and humid environments, the frost protection layer also becomes a very important part

  12. Asbestos in crushed stone: an overlooked aspect with potential of broader international research

    Science.gov (United States)

    Miskovsky, Karel; Prikryl, Richard

    2016-04-01

    Asbestos and related health effects became widely discussed issue during past decades, leading to serious decline in the use of this industrial mineral. Asbestos-like minerals are, however, quite common in several rock types that were and are still used as crushed stone. Unfortunately, there is still missing any broader concern on the detection of these fibrous minerals in aggregate source rocks, and consequently there is lack of knowledge on the potential impacts of the use of asbestos-bearing rocks on the environment and the society. This paper aims to present an introduction to this serious problem and to open a call for wider co-operation on the international level.

  13. Crush-2: Communicating research through a science-art collaboration

    Science.gov (United States)

    Mair, K.; Barrett, N.; Schubnel, A. J.; Abe, S.

    2011-12-01

    Historically, the Earth's environment and dynamics have influenced and inspired the arts. Art in turn is a powerful vehicle for expression of the natural world. It lends itself to public presentation in many forms and appeals to a diverse audience. Science-art collaborations provide a unique opportunity to connect with the public by taking science out of the classroom and into museums, galleries and public spaces. Here we investigate the use of contemporary digital sound-art in communicating geoscience research to the general public through the installation Crush-2. Crush-2, is an interactive sound-art installation exploring the microscopic forces released during the crushing of rock. Such processes have a strong influence on the sliding behaviour and hence earthquake potential of active faults. This work is a collaboration between sound artist and composer Natasha Barrett (Oslo) and geoscientists Karen Mair (University of Oslo), Alexandre Schubnel (Ecole Normale Superieure, Paris) and Steffen Abe (RWTH Aachen). Using a sonification technique, Barrett has assigned sound recorded from rocks, of different pitches, timbres and durations, to individual fracturing events produced in our 3D fault fragmentation models and laboratory rock breaking experiments. In addition, ultrasonic acoustic emissions recorded directly in the laboratory are made audible for our hearing and feature in the work. The installation space comprises a loudspeaker array and sensor enabled helmet with wireless headphones. By wearing the helmet, moving and listening, the audience explores an artistic interpretation of the scientific data in physical space. On entering the space, one is immediately immersed in a 3D cacophony of sound. Sustained or intermittent pings, burrs, plops and tingles jostle for position in our heads whilst high pitched delicate cascades juxtapose with deep thunder like rumbles. Depending on the user's precise path through the soundscape, the experience changes accordingly

  14. A new zebrafish bone crush injury model

    Directory of Open Access Journals (Sweden)

    Sara Sousa

    2012-07-01

    While mammals have a limited capacity to repair bone fractures, zebrafish can completely regenerate amputated bony fin rays. Fin regeneration in teleosts has been studied after partial amputation of the caudal fin, which is not ideal to model human bone fractures because it involves substantial tissue removal, rather than local tissue injury. In this work, we have established a bone crush injury model in zebrafish adult caudal fin, which consists of the precise crush of bony rays with no tissue amputation. Comparing these two injury models, we show that the initial stages of injury response are the same regarding the activation of wound healing molecular markers. However, in the crush assay the expression of the blastema marker msxb appears later than during regeneration after amputation. Following the same trend, bone cells deposition and expression of genes involved in skeletogenesis are also delayed. We further show that bone and blood vessel patterning is also affected. Moreover, analysis of osteopontin and Tenascin-C reveals that they are expressed at later stages in crushed tissue, suggesting that in this case bone repair is prolonged for longer than in the case of regeneration after amputation. Due to the nature of the trauma inflicted, the crush injury model seems more similar to fracture bone repair in mammals than bony ray amputation. Therefore, the new model that we present here may help to identify the key processes that regulate bone fracture and contribute to improve bone repair in humans.

  15. New rock salt-related oxides Li{sub 3}M{sub 2}RuO{sub 6} (M=Co, Ni): Synthesis, structure, magnetism and electrochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Laha, S. [Departamento de Químicas Inorganica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid (Spain); Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560 012 (India); Morán, E., E-mail: emoran@quim.ucm.es [Departamento de Químicas Inorganica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid (Spain); Sáez-Puche, R.; Alario-Franco, M.Á.; Dos santos-Garcia, A.J. [Departamento de Químicas Inorganica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid (Spain); Gonzalo, E.; Kuhn, A.; García-Alvarado, F. [Universidad CEU San Pablo, Facultad de Farmacia, Departamento de Química, 28668 Boadilla del Monte, Madrid (Spain); Sivakumar, T.; Tamilarasan, S.; Natarajan, S.; Gopalakrishnan, J. [Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560 012 (India)

    2013-07-15

    We describe the synthesis, crystal structure, magnetic and electrochemical characterization of new rock salt-related oxides of formula, Li{sub 3}M{sub 2}RuO{sub 6} (M=Co, Ni). The M=Co oxide adopts the LiCoO{sub 2} (R-3m) structure, where sheets of LiO{sub 6} and (Co{sub 2}/Ru)O{sub 6} octahedra are alternately stacked along the c-direction. The M=Ni oxide also adopts a similar layered structure related to Li{sub 2}TiO{sub 3}, where partial mixing of Li and Ni/Ru atoms lowers the symmetry to monoclinic (C2/c). Magnetic susceptibility measurements reveal that in Li{sub 3}Co{sub 2}RuO{sub 6}, the oxidation states of transition metal ions are Co{sup 3+} (S=0), Co{sup 2+} (S=1/2) and Ru{sup 4+} (S=1), all of them in low-spin configuration and at 10 K, the material orders antiferromagnetically. Analogous Li{sub 3}Ni{sub 2}RuO{sub 6} presents a ferrimagnetic behavior with a Curie temperature of 100 K. The differences in the magnetic behavior have been explained in terms of differences in the crystal structure. Electrochemical studies correlate well with both magnetic properties and crystal structure. Li-transition metal intermixing may be at the origin of the more impeded oxidation of Li{sub 3}Ni{sub 2}RuO{sub 6} when compared to Li{sub 3}Co{sub 2}RuO{sub 6}. Interestingly high first charge capacities (between ca. 160 and 180 mAh g{sup −1}) corresponding to ca. 2/3 of theoretical capacity are reached albeit, in both cases, capacity retention and cyclability are not satisfactory enough to consider these materials as alternatives to LiCoO{sub 2}. - Graphical abstract: Two new rock salt related oxides of formula, Li{sub 3}M{sub 2}RuO{sub 6}, (M=Co, Ni) have been prepared. The M=Co oxide adopts the LiCoO{sub 2} (R-3m) structure and the M=Ni oxide adopts a similar layered structure related to Li{sub 2}TiO{sub 3,} monoclinic (C2/c), with partial mixing of Li and Ni/Ru atoms. For Li{sub 3}Co{sub 2}RuO{sub 6}, oxidation state for Ru is 4+ and antiferromagnetic (AFM) order is

  16. Natural analogs in the host rock salt. Pt. 1. General study (2011). Pt. 2. Detail studies (2012-2013); Natuerliche Analoga im Wirtsgestein Salz. T. 1. Generelle Studie (2011). T. 2. Detailstudien (2012-2013)

    Energy Technology Data Exchange (ETDEWEB)

    Brasser, Thomas; Fahrenholz, Christine; Kull, Herbert; Meleshyn, Artur; Moenig, Heike; Noseck, Ulrich; Schoenwiese, Dagmar; Wolf, Jens

    2014-12-15

    The first part of the project ISIBELII on natural analogs in the host rock salt included a summary of available studies on the topic to be used in a safety analysis for a final repository for heat generating radioactive waste. In 2012 the results of the preliminary safety analysis Gorleben was available, including results on the fracturing of anhydrite, the formation of cryogenic gaps and the influence of earthquakes. The requirements for the barrier system have been modified due to the safety requirements for the final disposal of heat-generating radioactive wastes valid since 2010. For containers the functionality gas to be demonstrated for 500 years. The following issues are covered: natural analogs for the integrity demonstration of the geological barrier, natural analogs for the integrity demonstration of geotechnical barriers, natural analogs for the evaluation of release scenarios. The detail studies include anhydrite fracturing, salt grit compaction, chemical composition of fluid inclusions, thermal stability of salt rock, mechanical stability of salt rock, influence of earthquakes, qualified closures, iron corrosion, and microbial processes.

  17. Research to lessen the amounts of curing agents in processed meat through use of rock salt and carbon monoxide

    Science.gov (United States)

    Sakata, R.; Takeda, S.; Kinoshita, Y.; Waga, M.

    2017-09-01

    This study was carried out to examine the reddening of meat products due to the addition of natural yellow salt (YS) and carbon monoxide (CO). Following YS or NaCl addition at 2% to pork subsequent to nitrite (0∼100 ppm) treatment, color development due to this addition was analyzed visually. Heme pigment content in the meat was also determined spectrophotometrically. YS was found to bring about greater reddening than NaCl, indicating residual nitrite and nitrate content to be significantly higher in meat containing YS, through the amount of either was quite small. The amount of nitrite required for a red color to develop was noted to vary significantly from one meat product to another. CO treatment of pork caused the formation of carboxy myoglobin (COMb) with consequent reddening of the meat. COMb was shown to be heat-stable and form stably at pH 5.0 to ∼8.0 and to be extractable with water, but was barely extractable at all with acetone. Nitric oxide was found to have greater affinity toward myoglobin (Mb) than CO. Nitrosyl Mb was noted to be stable in all meat products examined. CO was seen to be capable of controlling the extent of lipid oxidation.

  18. Assessing the disturbed rock zone (DRZ) around a 655 meter vertical shaft in salt using ultrasonic waves: An update

    Energy Technology Data Exchange (ETDEWEB)

    HARDY,ROBERT D.; HOLCOMB,DAVID J.

    2000-03-14

    An array of ultrasonic transducers was constructed consisting of three identical arrays at various depths in an air intake shaft at the Waste Isolation Pilot Plant (WIPP). Each array consists of transducers permanently installed in three holes arranged in an L shape. An active array, created by appropriate arrangement of the transducers and selection of transmitter-receiver pairs, allows the measurement of transmitted signal velocities and amplitudes (for attenuation studies) along 216 paths parallel, perpendicular and tangential to the shaft walls. Transducer positions were carefully surveyed, allowing absolute velocity measurements. Installation occurred over a period of about two years beginning in early 1989, with nearly continuous operation since that time, resulting in a rare, if not unique, record of the spatial and temporal variability of damage development around an underground opening. This paper reports results from the last two years of operation, updating the results reported by Holcomb, 1999. Results will be related to the damage, due to microcracking, required to produce the observed changes. It is expected that the results will be useful to other studies of the long-term deformation characteristics of salt.

  19. Crushing or splitting medications: unrecognized hazards.

    Science.gov (United States)

    Gill, Donna; Spain, Margaret; Edlund, Barbara J

    2012-01-01

    Given the high use and the cost of medications in the current economy, one way older adults may save money on prescription costs is to split some of their medications in half. However, not all oral medications can be split. Splitting inappropriate medications such as extended-release tablets can be harmful and in some instances very dangerous. In addition to splitting medications, older adults who have difficulty swallowing pills may resort to crushing the medication for ease of administration. This option is also problematic and potentially harmful if the medication is not intended to be crushed. Clinicians managing the care of older adults need to discuss medication administration, clarify the dosing schedule, and clearly indicate the route of administration. Patients should be cautioned not to split or crush a medication without checking with the health care provider or pharmacist.

  20. An early warning method for crush

    CERN Document Server

    Harding, Peter J; Amos, Martyn

    2010-01-01

    Fatal crush conditions occur in crowds with tragic frequency. Event organisers and architects are often criticised for failing to consider the causes and implications of crush, but the reality is that the prediction and mitigation of such conditions offers a significant technical challenge. Full treatment of physical force within crowd simulations is precise but computationally expensive; the more common method of human interpretation of results is computationally "cheap" but subjective and time-consuming. In this paper we propose an alternative method for the analysis of crowd behaviour, which uses information theory to measure crowd disorder. We show how this technique may be easily incorporated into an existing simulation framework, and validate it against an historical event. Our results show that this method offers an effective and efficient route towards automatic detection of crush.

  1. Organic-rich shales from internal Betic basins (SE Spain): potential source rocks analogs for the pre-Messinian Salt play in the western Mediterranean

    Energy Technology Data Exchange (ETDEWEB)

    Permanyer, A.; Jorge, R.; Baudino, R.; Gilbert, L.

    2016-07-01

    Southeastern Spain has a large number of Late Neogene basins with substantial evaporitic deposits that developed under an overall NNW-SSE compressional regime related to the African-European tectonic plates collision. Located in the Betic Cordillera, they can be considered as marginal Mediterranean basins that became gradually isolated during the Tortonian and Early Messinian due to tectonic uplift. Different evaporitic units accumulated in these basins during isolation and, in several cases, evaporitic conditions were associated to episodes of important organic matter accumulation. Results obtained from Late Tortonian to Early Messinian shales collected from boreholes, mines and outcrops in the internal Betic basins of Las Minas de Hellín, Cenajo and Socovos are presented. The organic matter was studied under fluorescence and scanning electron microscopy (SEM), and the main geochemical characteristics defined. They show a relation between organic-rich intervals with high potential of hydrocarbon generation, native sulfur, bio-induced dolomite and evaporitic deposits. These organicrich shales can be found before, during and after the evaporitic episodes. Results from the present study are compared with those previously obtained in the pre-evaporitic deposits of the Lorca Basin that showed high oil generation potential, a restricted-marine origin of the organic matter and a low degree of maturity. The occurrence of such potential source rocks in several basins points to a broad regional distribution. At a larger scale, in the Mediterranean Basin, organic-rich sediments were deposited before and during the Messinian Salinity Crisis. The studied examples could represent analogs for potential source rocks of the pre-Messinian salt play in the Western Mediterranean. (Author)

  2. Crushing and Fracture of Lightweight Structures

    DEFF Research Database (Denmark)

    Urban, Jesper

    2003-01-01

    . Crushing experiments conducted on full-scale aluminum plate intersections reveal that the crushing behaviour is highly affected by material fracture during the deformation. Several fracture criteria from the literature have been reviewed and three fracture models have been compared with material...... criteria for first-ply failure of unidirectional composites (UD), from the literature, are compared with experiments conducted on composite specimens. It is found that a failure criterion by Chang and Chang (1987) agrees well with the experiments on UD. A progressive failure procedure by Chang and Chang...

  3. Distribution of crushing strength of tablets

    DEFF Research Database (Denmark)

    Sonnergaard, Jørn

    2002-01-01

    as a material constant. However, the estimation of this parameter is laborious and subject to estimation problems. It is shown that the Weibull modulus is inherently connected to the coefficient of variation and that the information obtained from the modulus is unclear. The distribution of crushing strength...... data from nine model tablet formulations and four commercial tablets are shown to follow the normal distribution. The importance of proper cleaning of the crushing strength apparatus is demonstrated. Copyright © 2002 Elsevier Science B.V....

  4. 钙芒硝盐岩溶蚀的角度效应%Experiment to Angle Effect of Glauberite Salt Rock Corrosion

    Institute of Scientific and Technical Information of China (English)

    刘欢; 徐素国

    2015-01-01

    In order to understand deeply dissolution characteristic of glauberite salt rock, and promote glauberite ore mining by water-solution and research to corrosion of glauberite interlayer in building salt cavern gas storage, dissolution rate and velocity of glauberite were studied by different angels in 35 degrees thermostatic water.The re-sults show that dissolution rate and velocity of glauberite are related to angles, and their values become bigger and bigger along with angles change from 90 to -90 degrees, therefore glauberite solution mining should adopt mining technique from bottom to top in favor of the upper and side solution.The expressions describing dissolution rate and velocity of glauberite along with angels and time change are obtained by using MATLAB to fit data, which have a certain guidance and reference value to solution mining glauberite ore and corrosion of glauberite interlayer in build-ing salt cavern gas storage.%为更深入的了解钙芒硝盐岩的溶解特性,促进水溶开采钙芒硝矿和盐穴储气库建造中钙芒硝夹层溶蚀的研究,对钙芒硝盐样以不同倾角在35℃恒温水中进行溶解速率和速度的实验。结果表明:钙芒硝在35℃恒温水中溶解速率和速度具有角度效应;倾角从90°~-90°变化时,溶解速率和速度越来越大,水溶采矿技术开采钙芒硝时应采用有利于上溶和侧溶,自下而上的开采技术;运用MATLAB对数据进行拟合,得出不同溶解角度下钙芒硝溶解速率和速度随时间变化规律的表达式,对水溶开采钙芒硝的相关研究和盐穴储气库夹层的溶蚀具有一定的指导和参考价值。

  5. Effects of the Indirect Ionic Interaction on the Diffusion of the Cation in the Silver Halide Crystals with the Rock-Salt Structure

    Science.gov (United States)

    Michihiro, Yoshitaka; Itsuki, Kazuya; Endou, Shigeki; Isono, Masaya; Nakamura, Koichi; Ohno, Takashi

    2013-07-01

    The contributions from the indirect ionic interaction to the activation energy for the diffusion of the cation by the vacancy mechanism are evaluated for the silver and sodium halide crystals with the rock-salt structure. The coupling constants of the indirect ionic interaction for the cations are calculated by the self-consistent field treatment of the local density approximation and the spherical solid model. The coupling constant of the indirect ionic interaction for Ag+ in AgBr is almost one order of magnitude larger than that for Na+ in NaBr. The strong indirect ionic interaction caused by the induced polarization of Ag+ in AgBr leads to the drastic decrease in the activation energy for the diffusion of Ag+. The difference between the strength of the indirect ionic interaction by Ag+ in AgBr and that by Na+ in NaBr reasonably explains the difference between the experimental activation energy for the diffusion of Ag+ in AgBr and that of Na+ in NaBr. The similar trend is also seen in AgCl and NaCl. These facts indicate that the strong non-central forces due to the indirect ionic interaction play an important role in the diffusion of Ag+.

  6. Storm Water General Permit 3 for Rock and Asphalt

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — General permit #3 for storm water discharges associated with industrial activity for Asphalt Plants, Concrete Batch Plants, Rock Crushing Plants and Construction...

  7. Study on the deterioration mechanism of layered rock-salt electrodes using epitaxial thin films - Li(Ni, Co, Mn)O2 and their Zr-O surface modified electrodes

    Science.gov (United States)

    Abe, Machiko; Iba, Hideaki; Suzuki, Kota; Minamishima, Hiroaki; Hirayama, Masaaki; Tamura, Kazuhisa; Mizuki, Jun'ichiro; Saito, Tomohiro; Ikuhara, Yuichi; Kanno, Ryoji

    2017-03-01

    Deterioration mechanism of Li(Ni, Co, Mn)O2 and Zr-O surface modified electrodes has been elucidated using epitaxial thin films synthesized by pulsed laser deposition. The electrodes comprise a mixture of layered rock-salt and spinel phases. The deterioration mechanism is analyzed using cyclic voltammetry, in situ X-ray diffraction measurements, and in situ neutron reflectometry. The spinel phase in the electrodes has low electrochemical activity and is not involved in Li insertion/extraction. The amount of Li participating in the charge-discharge reactions in the layered rock-salt phase increases with cycling, inducing a phase change at the electrode surface, lowering the reversibility. In contrast, in the Zr-O surface modified electrode, the spinel phase does not increase on charging/discharging. Thus, the Zr-O modification stabilizes the surface of layered rock-salt structure, thereby improving the cycling characteristics. Also, after the Zr-O modification, the Li concentration in the liquid electrolyte near the electrode/electrolyte interface increases during charging/discharging. The Zr-O surface modification not only stabilizes the electrode surface but also causes changes on the electrolyte side. Using the mixed model electrodes, we elucidate the mechanism of electrode deterioration and the origin of the improvement in cycling characteristics occurring on surface modification.

  8. Leaf Physiological and Proteomic Analysis to Elucidate Silicon Induced Adaptive Response under Salt Stress in Rosa hybrida ‘Rock Fire’

    Directory of Open Access Journals (Sweden)

    Prabhakaran Soundararajan

    2017-08-01

    Full Text Available Beneficial effects of silicon (Si on growth and development have been witnessed in several plants. Nevertheless, studies on roses are merely reported. Therefore, the present investigation was carried out to illustrate the impact of Si on photosynthesis, antioxidant defense and leaf proteome of rose under salinity stress. In vitro-grown, acclimatized Rosa hybrida ‘Rock Fire’ were hydroponically treated with four treatments, such as control, Si (1.8 mM, NaCl (50 mM, and Si+NaCl. After 15 days, the consequences of salinity stress and the response of Si addition were analyzed. Scorching of leaf edges and stomatal damages occurred due to salt stress was ameliorated under Si supplementation. Similarly, reduction of gas exchange, photosynthetic pigments, higher lipid peroxidation rate, and accumulation of reactive oxygen species under salinity stress were mitigated in Si treatment. Lesser oxidative stress observed was correlated with the enhanced activity and expression of antioxidant enzymes, such as superoxide dismutase, catalase, and ascorbate peroxidase in Si+NaCl treatment. Importantly, sodium transportation was synergistically restricted with the stimulated counter-uptake of potassium in Si+NaCl treatment. Furthermore, two-dimensional electrophoresis (2-DE and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS results showed that out of 40 identified proteins, on comparison with control 34 proteins were down-accumulated and six proteins were up-accumulated due to salinity stress. Meanwhile, addition of Si with NaCl treatment enhanced the abundance of 30 proteins and downregulated five proteins. Differentially-expressed proteins were functionally classified into six groups, such as photosynthesis (22%, carbohydrate/energy metabolism (20%, transcription/translation (20%, stress/redox homeostasis (12%, ion binding (13%, and ubiquitination (8%. Hence, the findings reported in this work could facilitate a

  9. Long-term cement corrosion in chloride-rich solutions relevant to radioactive waste disposal in rock salt - Leaching experiments and thermodynamic simulations

    Science.gov (United States)

    Bube, C.; Metz, V.; Bohnert, E.; Garbev, K.; Schild, D.; Kienzler, B.

    Low- and intermediate-level radioactive wastes are frequently solidified in a cement matrix. In a potential repository for nuclear wastes, the cementitious matrix is altered upon contact with solution and the resulting secondary phases may provide for significant retention of the radionuclides incorporated in the wastes. In order to assess the secondary phases formed upon corrosion in chloride-rich solutions, which are relevant for nuclear waste disposal in rock salt, leaching experiments were performed. Conventional laboratory batch experiments using powdered hardened cement paste in MgCl2-rich solutions were left to equilibrate for up to three years and full-scale cemented waste products were exposed to NaCl-rich and MgCl2-rich solutions for more than twenty years, respectively. Solid phase analyses revealed that corrosion of hardened cement in MgCl2-rich solutions advanced faster than in NaCl-rich solutions due to the extensive exchange of Mg from solution against Ca from the cementitious solid. Thermodynamic equilibrium simulations compared well to results at the final stages of the respective experiments indicating that close to equilibrium conditions were reached. At high cement product to brine ratios (>0.65 g mL-1), the solution composition in the laboratory-scale experiments was close to that of the full-scale experiments (cement to brine ratio of 2.5 g mL-1) in the MgCl2 systems. The present study demonstrates the applicability of thermodynamic methods used in this approach to adequately describe full-scale long-term experiments with cemented waste simulates.

  10. Modelling the crush behaviour of thermoplastic composites

    OpenAIRE

    Tan, Wei; Falzon, Brian G.

    2016-01-01

    Thermoplastic composites are likely to emerge as the preferred solution for meeting the high-volume production demands of passenger road vehicles. Substantial effort is currently being directed towards the development of new modelling techniques to reduce the extent of costly and time consuming physical testing. Developing a high-fidelity numerical model to predict the crush behaviour of composite laminates is dependent on the accurate measurement of material properties as well as a thorough ...

  11. An economic system that crushes the poor

    Directory of Open Access Journals (Sweden)

    Maake J. Masango

    2014-02-01

    Full Text Available The article focuses on economic structures that crush the poor, especially global economic structures that trap and keep people in poverty. The concept of poverty occupies centre stage in South Africa and many other developing countries. There is no longer a middle class. One is either rich or poor. Globalisation has created a system or program that continues to crush the poor, while also breeding greed and selfishness. The rich always accumulate resources while the poor struggle to make ends meet. These problems are created by the World Bank, the International Monetary Fund, and Structural Adjustment Programs, to name a few. These structures have introduced a system of inequality that widens the gap between the rich and the poor because of self-interest, which continues to crush the latter. The end result is that the concept of Ubuntu or Botho among African communities is destroyed. Injustice becomes the order of the day.

  12. Crush testing, characterizing, and modeling the crashworthiness of composite laminates

    Science.gov (United States)

    Garner, David Michael, Jr.

    Research in the field of crashworthiness of composite materials is presented. A new crush test method was produced to characterize the crush behavior of composite laminates. In addition, a model of the crush behavior and a method for rank ordering the energy absorption capability of various laminates were developed. The new crush test method was used for evaluating the crush behavior of flat carbon/epoxy composite specimens at quasi-static and dynamic rates. The University of Utah crush test fixture was designed to support the flat specimen against catastrophic buckling. A gap, where the specimen is unsupported, allowed unhindered crushing of the specimen. In addition, the specimen's failure modes could be clearly observed during crush testing. Extensive crush testing was conducted wherein the crush force and displacement data were collected to calculate the energy absorption, and high speed video was captured during dynamic testing. Crush tests were also performed over a range of fixture gap heights. The basic failure modes were buckling, crack growth, and fracture. Gap height variations resulted in poorly, properly, and overly constrained specimens. In addition, guidelines for designing a composite laminate for crashworthiness were developed. Modeling of the crush behavior consisted of the delamination and fracture of a single ply or group of like plies during crushing. Delamination crack extension was modeled using the mode I energy release rate, G lc, where an elastica approach was used to obtain the strain energy. Variations in Glc were briefly explored with double cantilever beam tests wherein crack extension occurred along a multidirectional ply interface. The model correctly predicted the failure modes for most of the test cases, and offered insight into how the input parameters affect the model. The ranking method related coefficients of the laminate and sublaminate stiffness matrices, the ply locations within the laminate, and the laminate thickness. The

  13. Bioaerosol formation during grape stemming and crushing.

    Science.gov (United States)

    Zollinger, Marc; Krebs, Walter; Brandl, Helmut

    2006-06-15

    Indoor formation of airborne particles during pre-fermentation grape processing was assessed by particle counting using laser particle sizers. Particle numbers of four different aerodynamic size classes (0.3 to 0.5 microm, 0.5 to 1 microm, 1 to 5 microm, and >5 microm) were determined during unloading of harvest containers and subsequent grape stemming and crushing. Regarding these size classes, composition before grape handling was determined as 87.9%, 10.4%, 1.7%, and 0.1%, respectively, whereas the composition changed during grape handling to 50.4%, 15.2%, 33.0%, and 1.5%, respectively. Airborne bacteria and fungi originating from grape processing were collected by impactor and liquid impinger samplers. Grape handling resulted in a sixfold increase in total (biological and non-biological) airborne particles. The generation of bacterial and fungal aerosols was associated mostly with particles of aerodynamic diameters>5 microm (mainly 7 to 11 microm) as determined by flow cytometry. This fraction was increased 150fold in relation to background levels before grape crushing. Maximum concentrations of culturable bacteria reached 485,000 colony forming units (cfu/m3), whereas 146,000 cfu of fungi and yeasts were detected per cubic meter of air. Culturable Gram-negative bacteria occurred only in small numbers (180 cfu/m3). In relation to the total number of airborne particles emitted, culturable microorganisms comprised 0.1% to 0.2%. As soon as grape crushing was stopped, particle concentrations decreased rapidly either due to passive settling or due to air currents in the occupational indoor environment reaching background levels.

  14. Radial crushing strength, microhardness and microstructure of molybdenum alloyed sintered steels

    Energy Technology Data Exchange (ETDEWEB)

    Candela, N.; Plaza, R.; Gordo, E.; Torralba, J.M. [Dept. de Ciencia de Materiales e Ing. Metalurgica, Univ. Carlos III de Madrid, Leganes (Spain); Rosso, M. [Materials Science and Chemical Eng. Dept., Politecnico di Torino (Italy)

    2001-07-01

    Prealloyed iron based powders with different Mo - Cu - Ni - C contents were uniaxially compacted at 700 MPa and sintered at 1120 C in nitrogen - hydrogen atmosphere. After sintering, all materials were thermochemically treated by plasma, gas and salt bath nitriding. The treatment's conditions were: plasma carbonitriding treatment at T=580 C in 76% N{sub 2}-19%H{sub 2}-5%CH{sub 4} atmosphere, gas nitriding treatment at T=750 C in 50% ENDO-50% NH{sub 3} atmosphere, salt bath nitriding treatment at T= 570 C during 2 h. with salt type Ternifer. Materials were evaluated through the study of radial crushing strength and a complete microstructural study was carried out using optical and scanning electron microscopy (SEM). Finally the fracture surface was analysed through SEM. (orig.)

  15. Self-assembly of ordered wurtzite/rock salt heterostructures—A new view on phase separation in Mg{sub x}Zn{sub 1−x}O

    Energy Technology Data Exchange (ETDEWEB)

    Gries, K. I.; Vogel, S.; Straubinger, R.; Beyer, A.; Chernikov, A.; Chatterjee, S.; Volz, K. [Faculty of Physics and Materials Sciences Center, Philipps-Universität Marburg, Hans-Meerwein-Straße 6 and Renthof 5, 35032 Marburg (Germany); Wassner, T. A.; Bruckbauer, J. [Walter Schottky Institut, Technische Universität München, Am Coulombwall 4, 85748 Garching (Germany); Häusler, I. [Institut für Physik, Humboldt-Universität zu Berlin, Newtonstraße 15, 12489 Berlin (Germany); Laumer, B. [Walter Schottky Institut, Technische Universität München, Am Coulombwall 4, 85748 Garching (Germany); I. Physikalisches Institut and Laboratorium für Materialforschung (LaMa), Justus-Liebig-Universität Gießen, Heinrich-Buff-Ring 16, 35392 Gießen (Germany); Kracht, M.; Heiliger, C.; Eickhoff, M. [I. Physikalisches Institut and Laboratorium für Materialforschung (LaMa), Justus-Liebig-Universität Gießen, Heinrich-Buff-Ring 16, 35392 Gießen (Germany); Janek, J. [Institute for Physical Chemistry and Laboratorium für Materialforschung (LaMa), Justus-Liebig-Universität Gießen, Heinrich-Buff-Ring 58, 35392 Gießen (Germany)

    2015-07-28

    The self-assembled formation of ordered, vertically stacked rocksalt/wurtzite Mg{sub x}Zn{sub 1−x}O heterostructures by planar phase separation is shown. These heterostructures form quasi “natural” two-dimensional hetero-interfaces between the different phases upon annealing of MgO-oversaturated wurtzite Mg{sub x}Zn{sub 1−x}O layers grown by plasma-assisted molecular beam epitaxy on c-plane sapphire substrates. The optical absorption spectra show a red shift simultaneous with the appearance of a cubic phase upon annealing at temperatures between 900 °C and 1000 °C. Transmission electron microscopy reveals that these effects are caused by phase separation leading to the formation of a vertically ordered rock salt/wurtzite heterostructures. To explain these observations, we suggest a phase separation epitaxy model that considers this process being initiated by the formation of a cubic (Mg,Zn)Al{sub 2}O{sub 4} spinel layer at the interface to the sapphire substrate, acting as a planar seed for the epitaxial precipitation of rock salt Mg{sub x}Zn{sub 1−x}O. The equilibrium fraction x of magnesium in the resulting wurtzite (rock salt) layers is approximately 0.15 (0.85), independent of the MgO content of the as-grown layer and determined by the annealing temperature. This model is confirmed by photoluminescence analysis of the resulting layer systems after different annealing temperatures. In addition, we show that the thermal annealing process results in a significant reduction in the density of edge- and screw-type dislocations, providing the possibility to fabricate high quality templates for quasi-homoepitaxial growth.

  16. Use Of Crushed Bricks As Coarse Aggregate In Concrete

    Directory of Open Access Journals (Sweden)

    Fadia S. Kalak

    2013-05-01

    Full Text Available The investigation reported in this paper is carried out to study the feasibility of using crushed bricks to substitute the coarse aggregate (gravel in concrete. Two types of concrete mixing are prepared. The first one is a mixture of  1:2:4 without crushed bricks and is used as a reference mixture .The second one is made of different weight of crushed bricks (as a percentage from the weight of the coarse aggregate. A total of 30 numbers of concrete specimens are casted with and without crushed bricks and  tested under compression and split tension as per relevant to British standard specifications.Test results indicated that using crushed bricks reduces the strength of concrete. Also, the percentage of water to cement ratio increases for constant slump when the percentage of crushed bricks increased.

  17. Numerical modelling of steel tubes under oblique crushing forces

    Science.gov (United States)

    Ismail, A. E.; Rahman, M. Q. Abdul; Nezere, N.; Jamian, S.; Kamarudin, K. A.; Awang, M. K.; Nor, M. K. Mohd; Ibrahim, M. N.; Rasidi Ibrahim, M.; Zulafif Rahim, M.; Fahrul Hassan, Mohd; Nor, Nik Hisyamudin Muhd; Arifin, A. M. T.; Zaini Yunos, Muhamad

    2017-08-01

    This paper presents the numerical assessment of crushing responses of elliptical tubes under crushing forces. Based on the literature survey, tremendous amount of works on the axial crushing behaviour can be found. However, the studies on the oblique crushing responses are rarely found. Therefore, this work investigates numerically the elliptical tubes under compressions. The numerical model of the tubes are developed using ANSYS finite element program. Two important parameters are used such as elliptical ratios and oblique angles. The tubes are compressed quasi-statically and the force-displacement curves are extracted. Then, the area under the curves are calculated and it is represented the performances of energy absorptions. It is found numerically that the introductions of oblique angles during the crushing processes decrease the crushing performances. However, the elliptical-shaped tubes capable to enhance the energy absorption capabilities. On the other hand, the elliptical-shaped tubes produced the enhancement on the energy absorption capabilities.

  18. Effect of Fracture on Crushing of Ship Structures

    DEFF Research Database (Denmark)

    Simonsen, Bo Cerup; Abramowicz, W.

    2003-01-01

    This paper is concerned with loads and energy absorption during crushing of ship structures. Particular focus is on the effect of fracture of welds or parent material on the energy absorption of typical structural subassemblies of ships during deep collapse. The paper presents experiments...... absorption in axial crushing of typical ship structural components. This effect of fracture has been neglected in previously published studies of bow crushing mechanics....

  19. Crushing of ship bows in head-on collision

    DEFF Research Database (Denmark)

    Ocakli, H.; Zhang, S.; Pedersen, Preben Terndrup

    2004-01-01

    Semi-analytical methods for analysis of plate crushing and ship bow damage in head-on collisions are developed in this paper. Existing experimental and theoretical studies for crushing analysis of plated structures are summarized and compared. Simple formulae for determining the crushing force....... The approach developed can be used easily to determine the crushing resistance and damage extent of the ship bow when ship length and collision speed are known. The method can be used in probabilistic analysis of damage extents in ship collisions where a large number of calculations are generally required....

  20. Optical and electron transport properties of rock-salt Sc{sub 1−x}Al{sub x}N

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Ruopeng; Zheng, P. Y.; Gall, D. [Department of Materials Science and Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)

    2015-07-07

    Epitaxial single-crystal Sc{sub 1−x}Al{sub x}N ternary alloy layers deposited by magnetron co-sputtering on MgO(001) substrates at 950 °C exhibit a solid solution rock-salt phase for x = 0–0.2 without decomposition. Optical absorption indicates a linear increase in the optical gap from 2.51 eV for ScN to 3.05 eV for Sc{sub 0.8}Al{sub 0.2}N and, after correction due to the Moss-Burstein shift, a direct X point interband transition energy E{sub g}(X) = 2.15 + 2.75 x (eV). Correspondingly, the direct transition at the zone center increases with Al concentration according to E{sub g}(Γ) = 3.80 + 1.45 x (eV), as determined from a feature in the reflection spectra. All layers are degenerate n-type semiconductors with a room temperature mobility that decreases from 22 to 6.7 to 0.83 cm{sup 2}/V s as x increases from 0 to 0.11 to 0.20. The corresponding carrier densities are 9.2 × 10{sup 20}, 7.9 × 10{sup 20}, and 0.95 × 10{sup 20 }cm{sup −3} as determined from Hall measurements and consistent with optical free carrier absorption below photon energies of 1 eV. Temperature dependent transport measurements indicate metallic conduction for ScN, but weak localization that leads to a resistivity minimum at 85 and 210 K for x = 0.051 and 0.15, respectively, and a negative temperature coefficient over the entire measured 4–300 K range for Sc{sub 0.8}Al{sub 0.2}N. The decreasing mobility is attributed to alloy scattering at randomly distributed Al atoms on cation sites, which also cause the weak localization. The carrier density is primarily due to unintentional F doping from the Sc target and decreases strongly for x > 0.15, which is attributed to trapping in defect states due to the deterioration of the crystalline quality, as evidenced by the x-ray diffraction peak width that exhibits a minimum of 0.14° for x = 0.11 but increases to 0.49° for x = 0.20. This is consistent with asymmetric x

  1. Mineral sources of water in evaporite sequences (salado salt and adjacent beds at the proposed waste disposal facility near Carlsbad in Lea and Eddy Counties, New Mexico)

    Energy Technology Data Exchange (ETDEWEB)

    Kopp, O.C.; Combs, D.W.

    1975-09-01

    Results of this study indicates that the Salado Salt is composed primarily of fine to coarse-grained halite with polyhalite, anhydrite, and clay minerals. Other minerals detected in small amounts include gypsum, magnesite, quartz, feldspar, sylvite, carnallite, celestite(question), glauconite, and kainite(question). Petrographic evidence (hopper crystals, and intergrowth of halite with other minerals) indicate that the Salado Salt was deposited in rather shallow water and may have been exposed subaerially at times. There must have been a major change in environmental conditions between the deposition of the Castile Formation and that of the Salado. The evidence also suggests that fluids have been able to move through the Salado Salt along beds and seams of clay and silt and somewhat along fractures. Water loss upon heating to 102 +- 5/sup 0/C ranges from 0.0 to 3.5 percent, considerably lower than those for Lyons, Kansas samples. Most of the dehydration water at 100/sup 0/C comes from clay minerals, while at higher temperatures, polyhalite contributes. The rock units in Salado Salt seem to release much less water when dehydrated than the Hutchinson Salt rocks at Lyons. During preparation of some of the samples, H/sub 2/S and possibly some natural gas were released when the samples were crushed. (DLC)

  2. Primary Analysis on Rock Salt Sedimentary Facies Area of Dawenkou Basin in Tai'an City%泰安市大汶口盆地岩盐沉积相区探析

    Institute of Scientific and Technical Information of China (English)

    张树淇; 郝瑞娥; 王浩

    2015-01-01

    Dongxiang depression Is a structural depression located in the west of Dawenkou basin.Favoura-ble structural conditions,ancient climate,geographical conditions,and the surrounding rich source formed rock salt deposit in the basin.Regional tectonic evolution caused sedimentary range and the concentration differences of brine.Thus,rock salt sedimentary facies have a certain evolution.The main tendency is a-long the direction of SWW from the northwest to the midwest of Dongxiang depression.The sedimentary thickness changes as well.%东向洼地是位于大汶口凹陷西部的构造洼地,有利的构造条件、古气候古地理条件、周边丰富的物源,形成了盆地内的岩盐矿床。区域构造演化,造成洼地内构造沉积幅度、卤水浓度差异,从而岩盐沉积相也有了一定的演化,主要趋势为沉积中心自沉积中心自东向洼地西北部沿走向 SWW 向向洼地中西部转移,沉积厚度也随之变化。

  3. 27 CFR 24.176 - Crushing and fermentation.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Crushing and fermentation..., DEPARTMENT OF THE TREASURY LIQUORS WINE Production of Wine § 24.176 Crushing and fermentation. (a) Natural... fermentation but the density of the juice may not be reduced below 22 degrees Brix. However, if the juice...

  4. [The prevention of crush syndrome related medical problems after earthquake].

    Science.gov (United States)

    Wang, Li; He, Qiang; Li, Gui-Sen

    2008-09-01

    Crush syndrome in patients rescued from earthquake is a complex clinical syndrome with many medical conditions. The most common complications are hyperkalemia, acute kidney injury, shock, infection, ARDS, malnutrition and multiorgan dysfunction. Managing these critical issues appropriately is essential for effective treatment of the crush syndrome.

  5. Reconsolidated Salt as a Geotechnical Barrier

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Francis D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gadbury, Casey [USDOE Carlsbad Field Office, NM (United States)

    2015-11-01

    Salt as a geologic medium has several attributes favorable to long-term isolation of waste placed in mined openings. Salt formations are largely impermeable and induced fractures heal as stress returns to equilibrium. Permanent isolation also depends upon the ability to construct geotechnical barriers that achieve nearly the same high-performance characteristics attributed to the native salt formation. Salt repository seal concepts often include elements of reconstituted granular salt. As a specific case in point, the Waste Isolation Pilot Plant recently received regulatory approval to change the disposal panel closure design from an engineered barrier constructed of a salt-based concrete to one that employs simple run-of-mine salt and temporary bulkheads for isolation from ventilation. The Waste Isolation Pilot Plant is a radioactive waste disposal repository for defense-related transuranic elements mined from the Permian evaporite salt beds in southeast New Mexico. Its approved shaft seal design incorporates barrier components comprising salt-based concrete, bentonite, and substantial depths of crushed salt compacted to enhance reconsolidation. This paper will focus on crushed salt behavior when applied as drift closures to isolate disposal rooms during operations. Scientific aspects of salt reconsolidation have been studied extensively. The technical basis for geotechnical barrier performance has been strengthened by recent experimental findings and analogue comparisons. The panel closure change was accompanied by recognition that granular salt will return to a physical state similar to the halite surrounding it. Use of run-of-mine salt ensures physical and chemical compatibility with the repository environment and simplifies ongoing disposal operations. Our current knowledge and expected outcome of research can be assimilated with lessons learned to put forward designs and operational concepts for the next generation of salt repositories. Mined salt

  6. Submarine Salt Karst Terrains

    Directory of Open Access Journals (Sweden)

    Nico Augustin

    2016-06-01

    Full Text Available Karst terrains that develop in bodies of rock salt (taken as mainly of halite, NaCl are special not only for developing in one of the most soluble of all rocks, but also for developing in one of the weakest rocks. Salt is so weak that many surface-piercing salt diapirs extrude slow fountains of salt that that gravity spread downslope over deserts on land and over sea floors. Salt fountains in the deserts of Iran are usually so dry that they flow at only a few cm/yr but the few rain storms a decade so soak and weaken them that they surge at dm/day for a few days. We illustrate the only case where the rates at which different parts of one of the many tens of subaerial salt karst terrains in Iran flows downslope constrains the rates at which its subaerial salt karst terrains form. Normal seawater is only 10% saturated in NaCl. It should therefore be sufficiently aggressive to erode karst terrains into exposures of salt on the thousands of known submarine salt extrusions that have flowed or are still flowing over the floors of hundreds of submarine basins worldwide. However, we know of no attempt to constrain the processes that form submarine salt karst terrains on any of these of submarine salt extrusions. As on land, many potential submarine karst terrains are cloaked by clastic and pelagic sediments that are often hundreds of m thick. Nevertheless, detailed geophysical and bathymetric surveys have already mapped likely submarine salt karst terrains in at least the Gulf of Mexico, and the Red Sea. New images of these two areas are offered as clear evidence of submarine salt dissolution due to sinking or rising aggressive fluids. We suggest that repeated 3D surveys of distinctive features (± fixed seismic reflectors of such terrains could measure any downslope salt flow and thus offer an exceptional opportunity to constrain the rates at which submarine salt karst terrains develop. Such rates are of interest to all salt tectonicians and the many

  7. IMPROVEMENT EFFECT OF PLAYGROUND SURFACE BY WASTE CRUSHED SHELL MIXING

    Science.gov (United States)

    Shigematsu, Hiroaki; Oda, Kenichi; Higuchi, Emiko; Takano, Morihiro; Tasaki, Hiroshi

    If sandy soil with appropriate gradation is compacted, hard and dense ground will be generated. Even if the soil material is hard enough against shock load, the permeability of the soil decreases significantly. This paper examines the improvement effect of playground surface by waste crushed shell mixing technique. The following conclusions are obtained from the present study: 1. The maximum dry density of the sandy soil increases gradually by mixing the crushed shell. However, if the crushed shell is put into the soil too much, the density decreases conversely. 2. Although the density of the soil sample becomes high by mixing the crushed shell, the coefficient of permeability increases. 3. The soil particles once attached to the shell is not washed away easily. 4. The crushed shell doesn't change the quality of groundwater so much. 5. This repair method is applicable to improvement of playground surface.

  8. Aespoe hard rock laboratory. Annual report 2000

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-06-01

    the repository system, which are of importance for long-term safety. The Prototype Repository experiment is focused on testing and demonstrating repository system function in full scale, and consists of six deposition holes with canisters and electric heaters surrounded by highly compacted bentonite. The work during 2000 has focused on geoscientific characterisation and specially hydraulic properties and conditions of the rock. Preparatory work with design, purchase and manufacturing as well as rock work (slots for the two plugs) have been going on with the aim of preparing for start of installation during the second quarter of 2001. Equipment for installation of bentonite blocks and canisters were tested before start of installation in the Canister Retrieval Test. This test was completed in October and the heaters as well as the artificial saturation system was turned on immediately thereafter. The objectives of the Demonstration of Repository Technology are to develop, test, and demonstrate methodology and equipment for encapsulation and deposition of spent nuclear fuel. The demonstration of handling and deposition is made with the specially designed full scale prototype to a deposition machine at 420 m level. The Backfill and Plug Test includes tests of backfill materials and emplacement methods and a test of a full-scale plug. Half the test part is filled with a mixture of 30% bentonite and crushed granite rock. The other half is filled with crushed rock without addition of bentonite, except for the upper 100-200 mm, where a slot was filled with blocks of highly compacted bentonite/crushed rock mixture and bentonite pellets. The backfill and rock has been instrumented with about 230 transducers for measuring the thermo- hydro-mechanical processes. Water saturation has been going on the whole year and the saturation speed has been slower than expected due to a lower salt content in the water than expected. In order to increase the speed a water with a higher salt

  9. Influences of petrographic parameters on technological properties of greywackes used for crushed stone production

    Science.gov (United States)

    Prikryl, Richard; Cermak, Martin; Krutilova, Katerina

    2014-05-01

    This study focuses on the influence of petrographic parameters on technological properties of greywackes. These sedimentary rocks make about 27 % of crushed stone market in the Czech Republic. Mainly in Moravia (eastern part of the Czech Republic), greywackes represent almost exclusive high quality aggregate. The behaviour of greywackes varies, however, from quarry to quarry. In this study, we have selected the most important deposits that cover major lithological variation of local greywackes. Studied greywackes were analysed for their petrographic parameters quantitatively (using image analysis of thin sections). The pore space characteristics were determined by using fluorescent dye - epoxy resin impregnated specimens. The studied rocks are composed of subangular and angular quartz grains, lithoclasts (stable rocks: quartzites, and unstable rocks: phylites, metaphylites, siltstones, slates, greywackes, and less frequently acid eruptive rocks), feldspars (orthoclas, microcline, plagioclase), and detrital micas. Detrital and authigenic chlorite has been found as well. The matrix which represents the largest volume of rock-forming components contains a mixture of sericite, chlorite, clay minerals, cements, and clasts in aleuropelitic size. Based on the microscopic examination, all studied rock types were classified as greywacke with fine- to medium-grained massive rock fabric. Only specimen from Bělkovice has shown partly layered structure. Alteration of feldspars and unstable rock fragments represents common feature. Diagenetic features included pressure dissolution of quartz clasts and formation of siliceous and/or calcite cements. Based on the experimental study of technological performance of studied greywackes and its correlation to petrographic features, the average size of clasts and volume of matrix make the driving factors affecting the LA values. The LA values decrease with the increasing of volume of matrix (R = 0.61) and with decreasing average grain

  10. Porosity and Permeability of Round Top Mountain Rhyolite (Texas, USA Favor Coarse Crush Size for Rare Earth Element Heap Leach

    Directory of Open Access Journals (Sweden)

    Lorraine Negron

    2016-02-01

    Full Text Available Water-saturation porosity and dye-penetration permeability measurements of Round Top Mountain rhyolite confirm that a ½-inch (13-mm crush size would permit efficient acid heap leaching of yttrium and heavy rare earth elements (YHREEs hosted in yttrofluorite, a YHREE-substituted variety of fluorite. Laboratory acid leaching has extracted up to 90% of the YHREEs. The bulk insoluble gangue mineralogy of the rhyolite, 90% to 95% quartz and feldspars, assures low acid consumption. Different crush sizes were weighed, soaked in water, and reweighed over time to determine water-penetration estimated porosity. Typical porosities were 1% to 2% for gray and 3% to 8% for pink varieties of Round Top rhyolite. The same samples were re-tested after soaking in dilute sulfuric to simulate heap leaching effects. Post-leach porosity favorably increased 15% in pink and 50% in gray varieties, due to internal mineral dissolution. Next, drops of water-based writing ink were placed on rhyolite slabs up to ~10 mm thick, and monitored over time for visual dye breakthrough to the lower side. Ink penetration through 0.5 to 2.5-mm-thick slabs was rapid, with breakthrough in minutes to a few hours. Pink rhyolite breakthrough was faster than gray. Thicker slabs, 4 to 10 mm, took hours to three days for breakthrough. Porosity and permeability of the Round Top rhyolite and acid solubility of the yttrofluorite host should permit liberation of YHREEs from the bulk rock by inexpensive heap leaching at a coarse and inexpensive nominal ½-inch (13-mm crush size. The rate-limiting step in heap leach extraction would be diffusion of acid into, and back-diffusion of dissolution products out of, the crushed particles. The exceptional porosity and permeability that we document at Round Top suggest that there may be other crystalline rock deposits that economically can be exploited by a coarse-crush bulk heap leach approach.

  11. Fluid distribution in grain boundaries of natural fine-grained rock salt deformed at low differential stress (Qom Kuh salt fountain, central Iran): Implications for rheology and transport properties

    NARCIS (Netherlands)

    Desbois, G.; Urai, J.L.; Bresser, J.H.P. de

    2012-01-01

    We used a combination of broad ion beam cross-sectioning and cryogenic SEM to image polished surfaces and corresponding pairs of fractured grain boundaries in an investigation of grain boundary microstructures and fluid distribution in naturally deformed halite from the Qom Kuh salt glacier (central

  12. 盐岩球腔储库弹性应力分布的理论解析%THEORETICAL ANALYTICAL SOLUTION OF STRESS DISTRIBUTION IN ELASTICITY STAGE OF SPHERICAL CAVITY STORAGE CAVERN IN SALT ROCK

    Institute of Scientific and Technical Information of China (English)

    王武; 许宏发; 江淼; 方秦

    2012-01-01

    假定地下储气库为球形腔体,利用在弹性阶段应力可叠加的基本原理,将球形储气库的受力方式简化分解为静水压力和垂直方向受力.对这2种受力方式下围岩应力分布解析结果进行叠加,获得在远场三轴压应力和储库内部压力共同作用下球腔储气库围岩弹性应力分布的完整解析解.在相同条件下,对盐岩球腔储气库进行数值分析,并将解析解与数值分析结果进行比较,结果表明,应力分布解析解与数值解吻合较好,验证所提出的分析方法是合理可行的.结合Hoek-Brown破坏准则,计算得出储气库不出现塑性破坏时的极限内压值范围.%Based on the assumption that the storage cavern is sphere, and using a basic principle that the stress could be superimposed in the elastic stage, the force modes of spherical gas storage cavern is disintegrated into hydrostatic pressure and vertical stress. Through the superposition of analytic results of surrounding rock stress distribution under the two kinds of force modes, the elastic stress distribution functions in surrounding rock of the spherical gas storage cavern in salt rock under remote field triaxial compressive stresses and internal pressure are derived. The numerical analysis of spherical gas storage cavern of salt rock is conducted under the same condition. Comparison shows that numerical simulation results are in good agreements with theoretical calculation results; and the presented analysis method is verified to be feasible. Then Hoek-Brown criterion is used to estimate the stability of spherical cavity storage cavern, and the limit of internal pressure is obtained when the plastic failure of gas storage cavern doesn't appear.

  13. Effects of in-plane magnetization orientation on magnetic and electronic properties in a Bcc Co (001)/rock salt MgO (001)/Bcc Co (001) magnetic tunnel junction system: ab initio calculations.

    Science.gov (United States)

    Yoo, Dong Su; Chae, Kisung; Chung, Yong-Chae

    2012-04-01

    Ab initio calculations were performed on a fully epitaxial bcc Co (001)/rock salt MgO (001)/bcc Co (001) magnetic tunnel junction system for two cases where the magnetization is parallel to bcc Co [100] and to bcc Co [110]. Structural optimization reveals that the two cases are equivalent systems and that the Co electrodes contract in the z-direction whereas the MgO insulating barrier expands. The magnetic moments of each monolayer vary slightly in each case; furthermore, only the magnetic moment at the surface of the Co atom shows any enhancement (12%). The layer decomposed density of states profiles reveals that the bonding character of the junction interface is derived mainly from the 2p-3d hybridization of the MgO and Co interfacial atoms.

  14. Crushed Stone Operations in the United States - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer includes crushed stone operations in the United States. These data were obtained from information reported voluntarily to the USGS by the aggregate...

  15. Prediction and Mitigation of Crush Conditions in Emergency Evacuations

    CERN Document Server

    Harding, Peter J; Gwynne, Steve

    2008-01-01

    Several simulation environments exist for the simulation of large-scale evacuations of buildings, ships, or other enclosed spaces. These offer sophisticated tools for the study of human behaviour, the recreation of environmental factors such as fire or smoke, and the inclusion of architectural or structural features, such as elevators, pillars and exits. Although such simulation environments can provide insights into crowd behaviour, they lack the ability to examine potentially dangerous forces building up within a crowd. These are commonly referred to as crush conditions, and are a common cause of death in emergency evacuations. In this paper, we describe a methodology for the prediction and mitigation of crush conditions. The paper is organised as follows. We first establish the need for such a model, defining the main factors that lead to crush conditions, and describing several exemplar case studies. We then examine current methods for studying crush, and describe their limitations. From this, we develop ...

  16. Salt ingestion caves.

    Directory of Open Access Journals (Sweden)

    Lundquist Charles A.

    2006-01-01

    Full Text Available Large vertebrate herbivores, when they find a salt-bearing layer of rock, say in a cliff face, can produce sizable voids where, overgenerations, they have removed and consumed salty rock. The cavities formed by this natural animal process constitute a uniqueclass of caves that can be called salt ingestion caves. Several examples of such caves are described in various publications. Anexample in Mississippi U.S.A., Rock House Cave, was visited by the authors in 2000. It seems to have been formed by deer orbison. Perhaps the most spectacular example is Kitum Cave in Kenya. This cave has been excavated to a length over 100 metersby elephants. An ancient example is La Cueva del Milodon in Chile, which is reported to have been excavated by the now extinctmilodon, a giant ground sloth. Still other possible examples can be cited. This class of caves deserves a careful definition. First, thecavity in rock should meet the size and other conventions of the locally accepted definition of a cave. Of course this requirement differsin detail from country to country, particularly in the matter of size. The intent is to respect the local conventions. The characteristicthat human entry is possible is judged to be a crucial property of any recognized cave definition. Second, the cavity should besignificantly the result of vertebrate animal consumption of salt-bearing rock. The defining process is that rock removed to form thecave is carried away in the digestive track of an animal. While sodium salts are expected to be the norm, other salts for which thereis animal hunger are acceptable. Also some other speleogenesis process, such as solution, should not be excluded as long as it issecondary in formation of a cave in question.

  17. Utilization of crushed clay brick in cellular concrete production

    OpenAIRE

    Ali A. Aliabdo; Abd-Elmoaty M. Abd-Elmoaty; Hani H. Hassan

    2014-01-01

    The main objective of this research program is to study the effect of using crushed clay brick as an alternative aggregate in aerated concrete. Two series of mixtures were designed to investigate the physico-mechanical properties and micro-structural analysis of autoclave aerated concrete and foamed concrete, respectively. In each series, natural sand was replaced with crushed clay brick aggregate. In both series results showed a significant reduction in unit weight, thermal conductivity and ...

  18. Laboratory evaluation of cement treated aggregate containing crushed clay brick

    Directory of Open Access Journals (Sweden)

    Liqun Hu

    2014-10-01

    Full Text Available The waste clay bricks from debris of buildings were evaluated through lab tests as environmental friendly materials for pavement sub-base in the research. Five sets of coarse aggregates which contained 0, 25%, 50%, 75% and 100% crushed bricks, respectively, were blended with sand and treated by 5% cement. The test results indicated that cement treated aggregate which contains crushed clay brick aggregate had a lower maximum dry density (MDD and a higher optimum moisture content (OMC. Moreover, the unconfined compressive strength (UCS, resilience modulus, splitting strength, and frost resistance performance of the specimens decreased with increase of the amount of crushed clay brick aggregate. On the other hand, it can be observed that the use of crushed clay brick in the mixture decreased the dry shrinkage strain of the specimens. Compared with the asphalt pavement design specifications of China, the results imply that the substitution rate of natural aggregate with crushed clay brick aggregate in the cement treated aggregate sub-base material should be less than 50% (5% cement content in the mixture. Furthermore, it needs to be noted that the cement treated aggregate which contains crushed clay bricks should be cautiously used in the cold region due to its insufficient frost resistance performance.

  19. THEORIES OF ROCK BREAKAGE WITH EXPLOSIVES

    Directory of Open Access Journals (Sweden)

    Vinko Škrlec

    2014-12-01

    Full Text Available The prediction and observation of the nature and dimensions of damaged zones in the surrounding rock mass and understanding the mechanisms of fracturing and crushing of the rock mass with explosives is one of the most important parameters in blasting design in order to obtain preferred granulation and reduce damaging effects of blasting on the environment. An overview of existing rock breakage theories with the energy released by the detonation of explosives is given in this paper (the paper is published in Croatian.

  20. Allelic Variants in Arhgef11 via the Rho-Rock Pathway Are Linked to Epithelial-Mesenchymal Transition and Contributes to Kidney Injury in the Dahl Salt-Sensitive Rat.

    Directory of Open Access Journals (Sweden)

    Zhen Jia

    Full Text Available Previously, genetic analyses identified that variants in Arhgef11 may influence kidney injury in the Dahl salt-sensitive (S rat, a model of hypertensive chronic kidney disease. To understand the potential mechanism by which altered expression and/or protein differences in Arhgef11 could play a role in kidney injury, stably transduced Arhgef11 knockdown cell lines as well as primary cultures of proximal tubule cells were studied. Genetic knockdown of Arhgef11 in HEK293 and NRK resulted in reduced RhoA activity, decreased activation of Rho-ROCK pathway, and less stress fiber formation versus control, similar to what was observed by pharmacological inhibition (fasudil. Primary proximal tubule cells (PTC cultured from the S exhibited increased expression of Arhgef11, increased RhoA activity, and up regulation of Rho-ROCK signaling compared to control (small congenic. The cells were also more prone (versus control to TGFβ-1 induced epithelial-mesenchymal transition (EMT, a hallmark feature of the development of renal interstitial fibrosis, and characterized by development of spindle shape morphology, gene expression changes in EMT markers (Col1a3, Mmp9, Bmp7, and Ocln and increased expression of N-Cadherin and Vimentin. S derived PTC demonstrated a decreased ability to uptake FITC-albumin compared to the small congenic in vitro, which was confirmed by assessment of albumin re-uptake in vivo by infusion of FITC-albumin and immunofluorescence imaging. In summary, these studies suggest that genetic variants in the S form of Arhgef11 via increased expression and/or protein activity play a role in promoting kidney injury in the S rat through changes in cell morphology (Rho-Rock and/or EMT that impact the function of tubule cells.

  1. Gas dispersion in untouched rock salt. Hydro-mechanically coupled model calculations using the simulation tool TFC; Gasausbreitung in unverritztes Steinsalz. Hydro-mechanisch gekoppelte Modellrechnungen mit dem Simulationstool TFC

    Energy Technology Data Exchange (ETDEWEB)

    Hotzel, Stephan

    2014-08-15

    Geological disposal of radioactive waste may give rise to gas injection into the host rock. The processes involved are subject of current research. In this study, the recently developed modelling tool TFC of GRS is used to model a number of coupled hydromechanical processes which may play a role in this scenario by means of a stylised gas injection experiment in rock salt. The simulation includes the gas emission phase, starting at the time of drilling the borehole, and the actual gas injection phase of the experiment. Rock salt is modelled as porous medium. Dependencies of hydrodynamic (H) parameters on mechanical (M) state changes (M→H-coupling) and of mechanical parameters on hydrodynamic state changes (H→M-coupling) are modelled by a number coupling functions. As to M→H-coupling, direct dependency of permeability on minimum effective stress is assumed as well as, alternatively, a poroelastic stress-porosity relationship with subsequent porosity-permeability relationship. As to H→M-coupling, independency between total stress and pore pressure is assumed as well as, alternatively, a poroelastic pore pressure vs. total stress relationship. Assuming direct dependency of permeability on effective stress, the simulations show that near the contour a permeability minimum develops in the emission phase, which does not vanish in the injection phase and which yields a very low gas flow. Assuming a mere poroelastic HM-coupling, gas emission is exceptionally low and also during the injection phase no enhanced gas injection can be achieved with this type of coupling. Apparently, pore volume changes in the framework of Biot's theory of poroelasticity are too small to result in such an effect. None of the various modelling assumptions results in a sudden injection of an actually large amount of gas. However, some simulations reveal an unexpected range of the injection front. Furthermore, a simulation with reduced bore hole diameter proves a scale dependency of

  2. Design and proof of function of a closure system for an HLW-repository in rock salt. Results of the preliminary safety analysis for the Gorleben site (VSG)

    Energy Technology Data Exchange (ETDEWEB)

    Mueller-Hoeppe, Nina; Breustedt, Michael; Engelhardt, Hans-Joachim; Wolf, Johanna [DBE Technology GmbH, Peine (Germany); Buhmann, Dieter; Czaikowski, Oliver; Herbert, Horst-Juergen; Wieczorek, Klaus; Xie, Mingliang [Gesellschaft fuer Anlagen- und Reaktorsicherheit mbH, Braunschweig (Germany)

    2015-07-01

    Within the preliminary safety analysis for the Gorleben site (VSG), a closure system was designed in order to complement the containment providing rock zone (CRZ) by sealing and backfilling measures. The design procedure as well as the technical proof of function was mainly performed according to standard procedures in civil engineering. In the context of VSG, rough individual technical proofs of several measures were carried out. Meanwhile, this gap has been closed by subsequent investigations. Altogether the results of all the individual technical proofs of function indicate that safe containment of radioactive waste is a realistic possibility at the Gorleben site.

  3. Long-Term Modeling of Coupled Processes in a Generic Salt Repository for Heat-Generating Nuclear Waste: Analysis of the Impacts of Halite Solubility Constraints

    Science.gov (United States)

    Blanco Martin, L.; Rutqvist, J.; Battistelli, A.; Birkholzer, J. T.

    2015-12-01

    Rock salt is a potential medium for the underground disposal of nuclear waste because it has several assets, such as its ability to creep and heal fractures and its water and gas tightness in the undisturbed state. In this research, we focus on disposal of heat-generating nuclear waste and we consider a generic salt repository with in-drift emplacement of waste packages and crushed salt backfill. As the natural salt creeps, the crushed salt backfill gets progressively compacted and an engineered barrier system is subsequently created [1]. The safety requirements for such a repository impose that long time scales be considered, during which the integrity of the natural and engineered barriers have to be demonstrated. In order to evaluate this long-term integrity, we perform numerical modeling based on state-of-the-art knowledge. Here, we analyze the impacts of halite dissolution and precipitation within the backfill and the host rock. For this purpose, we use an enhanced equation-of-state module of TOUGH2 that properly includes temperature-dependent solubility constraints [2]. We perform coupled thermal-hydraulic-mechanical modeling and we investigate the influence of the mentioned impacts. The TOUGH-FLAC simulator, adapted for large strains and creep, is used [3]. In order to quantify the importance of salt dissolution and precipitation on the effective porosity, permeability, pore pressure, temperature and stress field, we compare numerical results that include or disregard fluids of variable salinity. The sensitivity of the results to some parameters, such as the initial saturation within the backfill, is also addressed. References: [1] Bechthold, W. et al. Backfilling and Sealing of Underground Repositories for Radioactive Waste in Salt (BAMBUS II Project). Report EUR20621 EN: European Atomic Energy Community, 2004. [2] Battistelli A. Improving the treatment of saline brines in EWASG for the simulation of hydrothermal systems. Proceedings, TOUGH Symposium 2012

  4. Analysis of deformation & destruction mechanism and stability of F0 fault crush zone in Fangezhuang Coal Mine

    Institute of Scientific and Technical Information of China (English)

    LIU Wei-tao; WU Qiang; JI Bao-jing; ZHOU Rui-guang

    2007-01-01

    Under the mining influence, carried on the electron microscope, the thin section analysis and creep tests to the fault matter's original sample and five groups of duplication samples, which have three kinds of moisture. The results of those tests indicate that confining pressure effect, structure effect and moisture effect all have influence to fault matter's nature. Meanwhile, the distortion destruction and stability variation of fault crush zone are the main reason which causes water-inrush lag-effect. Simultaneously, the stimulation computation we made by the numerical simulation software FLAC 3D also describes the mining influence to floor strata, fault crush zone's range and size, the influence of confined water on overburden and the fault zones, also it describes the time effect of bearing influenced by confined water and the rock dank height of confined water along the fault zones influenced by the specific water head.

  5. Experimental study of a new multifunctional device for rock fragmentation

    Institute of Scientific and Technical Information of China (English)

    ZHAO Fu-jun(赵伏军); LI Xi-bing(李夕兵); FENG Tao(冯涛)

    2004-01-01

    A new multifunctional testing device for rock fragmentation was introduced, which can conduct many experiments such as single cutting under static load, crushing under impact load, thrusting under static load and cutting-impact test under the dynamic and static load. The results of granite and concrete's experiments with polycrystalline diamond compact (PDC) flat cutters and carbide alloy cutters under different loadings show that the device has good performance, and the characteristics of broken rock under the combined loads are similar to that under the single static pressure or impact crushing the rock, and the combined loads can increase the effect of rock fragmentation obviously. The experimental methods and effects have the important meaning for studying new drilling tool on hard rock fragmentation.

  6. 东濮凹陷下第三系沙河街组层序地层划分及盐岩成因探讨%Partition of Sequence Strata and Discussion aboutSalt- rock Resource in Shahejie Formation of Eogene, Dongpu Depression

    Institute of Scientific and Technical Information of China (English)

    陈发亮; 李绪涛; 朱晖; 苗翠芝

    2000-01-01

    Dongpu depression is located in the southwest of Bohai Bay basin. The area is about 5300 square kilometers.The south is wide and the north is narrow. Lanliao fault controls its development and evolvement. On the basis of sequence stratigraphic theory, the author analyzed of the geologic, seimic, geochemical, pale-obiological, drilling and logging data. There are two sequences (Sequence I and Sequence Ⅱ) and eight systemstracts(one sequence includes LST, TST, HST and FSST) has been identified in Shahejie and Dongying formation.They are all have clear characteristics in seimic, geologic, core and logging dada. In continental basin, the influ-ence of the three factors of tectonization, weather and sediments on sequence is different from that in marine basin,the weather is more important than that in marine sequence. After the synthetical analysis of sedimentary facies markers, the author has made the sedimentary lithofaciespaleogeographic reconstruction of Shahejie formation of Eogene in Dongpu depres-sion. In this paper the author also re- discussed the resource and the formation of salt - rock, which distributedwidely and has a large thickness. The characteristics of chemical components, paleobiota, lithology and distributionof the salt - rock are different from the normal evaporite. It is not come from the evaporation of sea water. Com-bined the paleotectogenesis and the paleoclimate, the result of the study indicates that the salt- rock is originatefrom the hot bittern in deep earth and formed under a deep - water environment with a moist climate in Dongpudepression. The formed model is due to an event abruptly. Development of salt - rock is related to tectonization of Lanliao fault but not the climate. The salt - rock is lo-cated in TST or HST and developed with source rock. It is advantageous to source rock by preventing it from oxy-gen. It can also provide heat and pressure for source rock to change into oil or gas. The salt - rock is tighter thanmudstone as

  7. 墨西哥湾深水岩膏地层钻井实践%Drilling practices of deepwater salt rock stratum in Gulf of Mexico

    Institute of Scientific and Technical Information of China (English)

    张星星; 黄小龙; 严德; 冷雪霜; 田瑞瑞

    2015-01-01

    在墨西哥湾大陆架外深水区域的水下存在大量的油气资源,在钻探过程中遇到了完全不同于以往的技术障碍,产层被分布广泛的巨厚盐层所覆盖,对通常采用的钻井和完井技术是一个巨大的挑战。对如何利用先进的钻井工具、工艺和钻井液管理方法解决巨厚盐层带来的钻井难点进行了论述,探讨了如何在满足深水开发的特殊经济和技术需求的同时实现上述目标。墨西哥湾地区已经完成了盐下远景区的勘探工作,目前已进入开发和生产阶段。%There are abundant oil and gas resources underwater in the deepwater areas outside the continental shelf in the Gulf of Mexico. During the drilling and exploration, the technical obstacles encountered were completely different from those previously met. These production layers are covered by the widely distributed and tremendously thick salt beds, posing a great challenge to the common drilling and completion technologies. How to make use of advanced drilling tools, processes and drilling lfuid management methods to settle the drilling dififculties due to the tremendously thick salt beds has been expounded, and how to meet the special economic and technical requirements of deepwater development while realizing the abovementioned goals has been discussed. The perspective explo-ration below the under-salt has been ifnished in the Gulf of Mexico. Currently, it has entered the development and production stages.

  8. Crushing performance and resource characteristic of printed circuit board scrap

    Institute of Scientific and Technical Information of China (English)

    WANG Hui; GU Guo-hua; QI Yun-feng

    2005-01-01

    The crushing performance of printed circuit board (PCB) was studied on several crushers. The results show that PCB is a material which is difficult to crush. The crushing performance of PCB with disk crusher, especially vibration grinding, which has cut or impact action, excels that of jaw crusher or roller crusher. The PCB scrap is worthwhile to recycle using variety of modern characterization methods. When compared with natural resources, this material stream remains a rich precious metal and nonferrous metals. In PCB scrap, metals account for 47% of the total material composition, in which there exists 19.66% copper, 11.47% iron, 3.93% lead, 300 g/t gold and 5-10 kg/t silver, etc. In addition, the PCB scrap contains 27% of plastics and 26% of refractory oxides.

  9. Size distribution of wet crushed waste printed circuit boards

    Institute of Scientific and Technical Information of China (English)

    Tan Zhihai; He Yaqun; Xie Weining; Duan Chenlong; Zhou Enhui; Yu Zheng

    2011-01-01

    A wet impact crusher was used to breakdown waste printed circuit boards (PCB's) in a water medium.The relationship between the yield of crushed product and the operating parameters was established.The crushing mechanism was analyzed and the effects of hammerhead style,rotation speed,and inlet water volume on particle size distribution were investigated.The results show that the highest yield of -1 + 0.75 mm sized product was obtained with an inlet water volume flow rate of 5.97 m3/h and a smooth hammerhead turning at 1246.15 r/min.Cumulative undersize-product yield curves were fitted to a nonlinear function:the fitting correlation coefficient was greater than 0.998.These research results provide a theoretical basis for the highly effective wet crushing of PCB's.

  10. Utilization of crushed clay brick in cellular concrete production

    Directory of Open Access Journals (Sweden)

    Ali A. Aliabdo

    2014-03-01

    Full Text Available The main objective of this research program is to study the effect of using crushed clay brick as an alternative aggregate in aerated concrete. Two series of mixtures were designed to investigate the physico-mechanical properties and micro-structural analysis of autoclave aerated concrete and foamed concrete, respectively. In each series, natural sand was replaced with crushed clay brick aggregate. In both series results showed a significant reduction in unit weight, thermal conductivity and sound attenuation coefficient while porosity has increased. Improvement on compressive strength of autoclave aerated concrete was observed at a percentage of 25% and 50% replacement, while in foamed concrete compressive strength gradually decreased by increasing crushed clay brick aggregate content. A comparatively uniform distribution of pore in case of foamed concrete with natural sand was observed by scanning electron microscope, while the pores were connected mostly and irregularly for mixes containing a percentage higher than 25% clay brick aggregate.

  11. Crushing damage estimation for pavement with lightly cementitious bases

    CSIR Research Space (South Africa)

    De Beer, Morris

    2014-07-01

    Full Text Available , Pretoria, South Africa. De Beer, M. 2013. Revision of the South African Pavement Design Method. Project Focus Area: Bound Materials: Damage Laws. Cementitious Materials: Expanded/Revised Damage Laws for Crushing Failure. Contract Report SANRAL/SAPDM-D3... stream_source_info De Beer_2014.pdf.txt stream_content_type text/plain stream_size 25820 Content-Encoding UTF-8 stream_name De Beer_2014.pdf.txt Content-Type text/plain; charset=UTF-8 CRUSHING DAMAGE ESTIMATION...

  12. Collecting Rocks

    Institute of Scientific and Technical Information of China (English)

    孙铮

    2007-01-01

    My hobby is collecting rocks.It is very special,isn’t it?I began to collect rocks about four years ago.I usually go hiking in the mountains,or near the river to look for rocks.When I find a rock,I pick it up and clean it with the brush and water.Then I put it into my bag.Most of the rocks I have collected are quartzite~*.They are really

  13. Stability of Crushed Tedizolid Phosphate Tablets for Nasogastric Tube Administration.

    Science.gov (United States)

    Kennedy, Gerard; Osborn, Jim; Flanagan, Shawn; Alsayed, Najy; Bertolami, Shellie

    2015-12-01

    Tedizolid phosphate is approved for the treatment of acute bacterial skin and skin structure infections. To determine whether the expected dose of tedizolid phosphate can be delivered via nasogastric tube in patients who have difficulty swallowing and in whom venous access is not suitable, this in vitro study evaluated the recovery of tedizolid phosphate 200-mg tablets after crushing, dispersion in water, and passage through a nasogastric tube. To analyze the chemical stability of the crushed tablet dispersed in water, the aqueous preparation was assayed initially after dispersion and again after 4 h at room temperature. Recovery of tedizolid phosphate after the crushed tablets were dispersed in water and passed through nasogastric tubes ranged from 92.5 to 97.1 %, which is within the specified acceptance criteria of 90 to 110 %. There was no significant change in recovery values after 4 h of storage at room temperature (93.9 % initially and 94.7 % after 4 h). The stability and recovery findings support the feasibility of administering an aqueous dispersion of crushed tedizolid phosphate tablets through a nasogastric tube in patients who have difficulty swallowing and in whom intravenous administration is not possible.

  14. A comparison of crushed ice and continuous flow cold therapy.

    Science.gov (United States)

    Barber, F A

    2000-01-01

    Crushed ice was compared to continuous flow cold therapy for control of postoperative pain after arthroscopic patellar tendon autograft anterior cruciate ligament (ACL) reconstruction. With all other variables held constant, cold was administered by either continuous flow (group 1) or crushed ice (group 2). The cold therapy was constant for 3 days, then as needed in days 4 through 7. Data were collected by investigator evaluations and patient diaries. Pain was assessed by visual analog scale (VAS) and categorical pain scale (Likert). Eighty-seven patients were included (52 continuous flow and 35 crushed ice). Continuous passive motion averaged 54 hours for group 1 and 43 hours for group 2 (Pcold therapy lowered VAS and Likert pain scores more, reduced hydrocodone bitartrate with acetaminophen use, was used more often, increased continuous passive motion, increased 1-week knee flexion, and was given significantly higher performance ratings by patients. Continuous flow cold is superior to crushed ice for outpatient ACL reconstruction pain and should not be considered an equivalent modality.

  15. FORMALIZATION OF MINIMUM POWER CONSUMPTION CRITERION FOR CRUSHING UNIT

    Directory of Open Access Journals (Sweden)

    M. Y. Shpurgalova

    2014-01-01

    Full Text Available Analytical expressions describing dependence between basic parameters of potash ore crushing process have been constructed in the paper. While taking in account the generality of the Kirpichev formula some corrections have been made for direct applicability of the given hypothesis in calculation of energy which is required for crushing of potash ore specimen. Such approach makes it possible to consider not only general averaged size of specimens but percentage content of every concrete specimen of the specified dimensions. While investigating potash ore composition of the prescribed volume it has been established that every component contained in the specimen composition has its tensile strength and elastic modulus. In addition to this it has been demonstrated the percentage content of components in potash ore composition (sylvinite, halite and insoluble residue is different.It has been experimentally determined that the selected volume of the material (2 м3 supplied for benefication and the final product have normal distribution of ore pieces, it means that number of averaged size pieces is higher than pieces of minimum and maximum sizes. An expression has been obtained on the basis of the executed investigations and formula that corresponds to the Kirpichev hypothesis. The expression makes it possible to calculate energy required for crushing of the specified volume of potash ore. In this case chemical composition and percentage content of components included in the potash ore have been taken into account. The energy required for crushing of the potash ore volume consists of total sum of energy used for crushing of separate components included in chemical composition of potash ore and this sum is multiplied by percentage content of corresponding substance.

  16. Comparison of current constitutive models and modeling procedures on the basis of calculations of the thermomechanical and healing behavior of rock salt. Report on the partial project 3; Modellrechnungen zum thermomechanischen Verhalten und zur Verheilung von Steinsalz. Ergebnisbericht zum Teilprojekt 3

    Energy Technology Data Exchange (ETDEWEB)

    Pudewills, Alexandra

    2016-07-01

    Between October 2010 and July 2016, the German Federal Ministry for Economic Affairs and Energy (German abbreviation BMWi) has funded a joint project within its research program ''Improvement of tools for the safety assessment of underground repositories''. The aim of benchmark calculations was to check the ability of the involved models to describe the temperature influence on deformation, the damage and dilatancy reduction and healing of rock salt.

  17. Evaluation of crushed ticagrelor tablet doses: recovery following crushing and naso-gastric tube passage ex vivo.

    Science.gov (United States)

    Crean, Barry; Finnie, Cindy; Crosby, Anna

    2013-06-01

    Orally available ticagrelor in combination with low-dose aspirin (75-100 mg/day) is indicated for adult patients with acute coronary syndromes. However, patients with swallowing difficulties may be unable to consume the currently available 90-mg tablet. It is hypothesized that ticagrelor could be given to this patient cohort as a crushed dose administered either orally or via a naso-gastric (NG) tube. To investigate the potential use of crushed ticagrelor tablets (90- and 180-mg doses) for oral dose or NG tube administration. Ticagrelor tablets (90 or 180 mg [two 90-mg tablets]) were prepared to emulate oral and NG tube administration by similar methods. For the oral dose, ticagrelor tablets were crushed using a mortar and pestle and transferred to a dosing cup. 100 mL of water was added to the mortar, stirred, and the contents were transferred to the dosing cup and stirred to form a suspension. At this stage, where the suspension would normally be administered to a patient, it was collected for high performance liquid chromatography (HPLC) analysis. The mortar was then flushed with 100 mL of water, and the contents were again transferred to the dosing cup, stirred, and collected for HPLC analysis. For the NG dose, polyvinylchloride, polyurethane, and silicone size CH10 NG tubes were used. The tablets were crushed using a mortar and pestle, diluted with 50 mL of water, and stirred. At this stage, where the suspension would normally be administered to a patient through an NG tube using a syringe, it was collected for HPLC analysis. The mortar was then flushed with two additional 50 mL aliquots of water and the contents were passed through the NG tube. HPLC analysis examined the recoverability of ticagrelor in each of the dose suspensions and flushes and the stability of the suspension when held in a syringe for up to 2 h. One or two crushed 90-mg ticagrelor tablets, prepared for either oral or NG tube administration, delivers a mean dose of ≥97% of the original

  18. Coronary bifurcation lesions treated with double kissing crush technique compared to classical crush technique: serial intravascular ultrasound analysis.

    Science.gov (United States)

    Shan, Shou-Jie; Ye, Fei; Liu, Zhi-Zhong; Tian, Nai-Liang; Zhang, Jun-Jie; Chen, Shao-Liang

    2013-04-01

    The double kissing (DK) crush technique is a modified version of the crush technique. It is specifically designed to increase the success rate of the final kissing balloon post-dilatation, but its efficacy and safety remain unclear. Data were obtained from the DKCRUSH-I trial, a prospective, randomized, multi-center study to evaluate safety and efficacy. Post-procedural and eight-month follow-up intravascular ultrasound (IVUS) analysis was available in 61 cases. Volumetric analysis using Simpson's method within the Taxus stent, and cross-sectional analysis at the five sites of the main vessel (MV) and three sites of the side branch (SB) were performed. Impact of the bifurcation angle on stent expansion at the carina was also evaluated. Stent expansion in the SB ostium was significantly less in the classical crush group ((53.81 ± 13.51)%) than in the DK crush group ((72.27 ± 11.46)%) (P = 0.04). For the MV, the incidence of incomplete crush was 41.9% in the DK group and 70.0% in the classical group (P = 0.03). The percentage of neointimal area at the ostium had a tendency to be smaller in the DK group compared with the classical group ((16.4 ± 19.2)% vs. (22.8 ± 27.1)%, P = 0.06). The optimal threshold of post-procedural minimum stent area (MSA) to predict follow-up minimum lumen area (MLA) kissing balloon inflation (FKBI) and had smaller optimal cutoff value of post-procedural MSA at the SB ostium.

  19. Functional and Molecular Changes of the Bladder in Rats with Crushing Injury of Nerve Bundles from Major Pelvic Ganglion to the Bladder: Role of RhoA/Rho Kinase Pathway

    Directory of Open Access Journals (Sweden)

    Tae-Kon Hwang

    2013-08-01

    Full Text Available Voiding dysfunction is a common complication after radical pelvic surgery. To reduce this complication, nerve-sparing radical pelvic surgery was introduced. However, several patients experienced voiding difficulty despite nerve-sparing radical pelvic surgery. Thus, we investigated the functional and molecular changes of the bladder in rats, which demonstrated voiding dysfunction induced by nerve damage during nerve-sparing radical pelvic surgery. Male rats were used and assigned to normal, sham-operated, and bilateral crushing nerve bundles from major pelvic ganglion (MPG to bladder group. After one, two, and four-week crushing injury, significantly decreased contractile response and increased connective tissue of the detrusor were observed and these results were reliable findings with voiding difficulty following nerve-sparing radical pelvic surgery. After crushing injury, significantly increased M2 muscarinic receptor expression was observed and this might be regarded as the compensatory response. However, M3 muscarinic receptor expression was not significantly changed. The expression of RhoA, ROCK-α, and ROCK-β was significantly increased after one, two, and four-week crushing injury. From these results, the down-regulation of RhoA/Rho kinase pathway might lead to the decreased bladder contractility after crushing injury of nerve bundles from MPG to the bladder despite of the compensated up-regulation of M2 muscarinic receptor.

  20. 49 CFR 587.15 - Verification of aluminum honeycomb crush strength.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Verification of aluminum honeycomb crush strength... Deformable Barrier § 587.15 Verification of aluminum honeycomb crush strength. The following procedure is used to ascertain the crush strength of the main honeycomb block and the bumper element honeycomb,...

  1. Rock Stars

    Institute of Scientific and Technical Information of China (English)

    张国平

    2000-01-01

    Around the world young people are spending unbelievable sums of money to listen to rock music. Forbes Magazine reports that at least fifty rock stars have incomes between two million and six million dollars per year.

  2. KREEP Rocks

    Institute of Scientific and Technical Information of China (English)

    邹永廖; 徐琳; 欧阳自远

    2004-01-01

    KREEP rocks with high contents of K, REE and P were first recognized in Apollo-12 samples, and it was confirmed later that there were KREEP rock fragments in all of the Apollo samples, particularly in Apollo-12 and-14 samples. The KREEP rocks distributed on the lunar surface are the very important objects of study on the evolution of the moon, as well as to evaluate the utilization prospect of REE in KREEP rocks. Based on previous studies and lunar exploration data, the authors analyzed the chemical and mineral characteristics of KREEP rocks, the abundance of Th on the lunar surface materials, the correlation between Th and REE of KREEP rocks in abundance, studied the distribution regions of KREEP rocks on the lunar surface, and further evaluated the utilization prospect of REE in KREEP rocks.

  3. Rock Art

    Science.gov (United States)

    Henn, Cynthia A.

    2004-01-01

    There are many interpretations for the symbols that are seen in rock art, but no decoding key has ever been discovered. This article describes one classroom's experiences with a lesson on rock art--making their rock art and developing their own personal symbols. This lesson allowed for creativity, while giving an opportunity for integration…

  4. Rock Art

    Science.gov (United States)

    Henn, Cynthia A.

    2004-01-01

    There are many interpretations for the symbols that are seen in rock art, but no decoding key has ever been discovered. This article describes one classroom's experiences with a lesson on rock art--making their rock art and developing their own personal symbols. This lesson allowed for creativity, while giving an opportunity for integration…

  5. Rock Finding

    Science.gov (United States)

    Rommel-Esham, Katie; Constable, Susan D.

    2006-01-01

    In this article, the authors discuss a literature-based activity that helps students discover the importance of making detailed observations. In an inspiring children's classic book, "Everybody Needs a Rock" by Byrd Baylor (1974), the author invites readers to go "rock finding," laying out 10 rules for finding a "perfect" rock. In this way, the…

  6. 岩盐椭球储气库应力解析及其稳定性分析%Stress Solutions and Stability Analysis of Ellipsoidal Gas Storage Cavern in Salt Rock

    Institute of Scientific and Technical Information of China (English)

    许宏发; 王武; 方秦; 赵佩胜

    2012-01-01

    岩盐地下储气库根据成腔方式不同,储气库形状也有较大变化,但简化为细长旋转椭球体(短长轴比s)是合理的.假定岩盐体为无限大各向同性线弹性体,将旋转椭球岩盐储气库受力分解为两种受力状态:有内压的静水压力状态和无内压的非静水压力状态.利用弹性理论应力叠加原理,求得了在地应力场(垂直p,水平Po)和内压(pi)作用下储气库腔壁上关键点(顶点和赤道线上任意点)的应力精确解析解.对某岩盐储气库进行了数值模拟计算,数值计算结果与解析解较接近.分析了关键点应力随椭球腔形状、地应力和内压的变化规律,认为径向应力随内压比(pi/p)的增加而增加,几乎与轴比(s)无关;水平环向应力随内压比和轴比的增加而减小.结合已有试验资料,确定了盐岩广义Hoek-Brown破坏模型参数,并据此计算得到了储气库不出现破坏时的极限内压值范围,当s=0.9时极限内压较小.%The shapes of the gas storage caverns vary with building ways, but simplified as an elongated rotational ellipsoid ( minor to major axis ratio, s ) is reasonable. Assumed that the ellipsoidal cavity is in linear elasticity and isotropy infinite body, the mechanical status of the caverns can be resolved into: hydrostatic pressure with internal pressure and non-hydrostatic pressure without internal pressure. Using principle of superposition on stress in elastic theory, the exact stress solutions for the key points,which are the peak and an arbitrary point on the equator line of the ellipsoidal cavity, were solved under geostress field ( vertical stress, p; horizontal stress ,p0 ) and internal pressure(pi). The numerical simulation analysis on rotational ellipsoidal gas storage cavern in salt rock was conducted, and the results of numerical simulation coincided with analytic solutions. Analyzed the laws of the stresses of the key points varying with shape of cavity, geostresses and internal

  7. Some influences of rock strength and strain rate on propagation of rock avalanches

    Science.gov (United States)

    Bowman, Elisabeth; Rait, Kim

    2016-04-01

    Rock avalanches are extreme and destructive mass movements in which large volumes of rock (typically >1 million cubic metres) travel at high speeds, covering large distances, and the occurrence of which is highly unpredictable. The "size effect" in rock avalanches, whereby those with larger volumes produce greater spreading efficiency (as defined by an increase in normalised runout) or lower farboschung angle (defined as the tangent of the ratio of fall height to runout length), is well known. Studies have shown that rock strength is a controlling factor in the mobility of rock avalanches - that is, mass movements involving lower strength rock are generally found to produce greater mobility as evidenced by the spread of deposits or low farboschung angle. However, there are conflicting ideas as to how and why this influence is manifested. This paper discusses different theories of rock comminution in light of numerical simulations of rock clasts undergoing normal and shear induced loading, experimental work on rock avalanche behaviour, and dynamic fracture mechanics. In doing so, we introduce the idea of thresholds of strain rate for the production of dynamic fragmentation (as opposed to pseudo-static clast crushing) that are based, inter alia, on static rock strength. To do this, we refer to data from physical models using rock analogue materials, field data on chalk cliff collapses, and field statistics from documented rock avalanches. The roles of normal and shear loading and loading rate within a rock avalanche are examined numerically using 3D Discrete Element Method models of rock clasts loaded to failure. Results may help to reconcile the observations that large rock avalanches in stronger materials tend not to fragment as much as those in weaker materials and also possess lower mobility, while small cliff collapses (typically > 1000 cubic metres) in weak chalk can exhibit rock avalanche-like behaviour at much smaller volumes.

  8. Control system of roll crushes in emergency situations

    Science.gov (United States)

    Nikitin, A. G.; Tagiltsev-Galeta, K. V.; Chaynikov, K. A.

    2017-09-01

    The system of emergency control of a roll crusher is developed, which allows the hardness of the crushed material to be evaluated indirectly estimating the current strength of the unit, or directly by swing of the deflecting the crusher jaw, and the pieces with the increased hardness to be recrushed, increasing compression, reducing the motor rotation frequency. This system reduces the number of emergencies and provides less downtime for equipment in the event of an accident than crushers using conventional safety elements: toggle plates and restraining spring or hydraulic fuses. Besides, this system is extensible, i.e. it does not interfere with the inclusion of additional devices (for example, mechanical breakers such as toggle plates), sensors (for example, angle protractor to improve the accuracy of measurements). With the combined use of direct and indirect evaluation of the crusher condition the accuracy and efficiency of the crusher control increases improving the reliability of a crushing unit as a whole.

  9. Coronary bifurcation lesions treated with double kissing crush technique compared to classical crush technique: serial intravascular ultrasound analysis

    Institute of Scientific and Technical Information of China (English)

    SHAN Shou-jie; YE Fei; LIU Zhi-zhong; TIAN Nai-liang; ZHANG Jun-jie; HEN Shao-liang

    2013-01-01

    Background The double kissing (DK) crush technique is a modified version of the crush technique.It is specifically designed to increase the success rate of the final kissing balloon post-dilatation,but its efficacy and safety remain unclear.Methods Data were obtained from the DKCRUSH-I trial,a prospective,randomized,multi-center study to evaluate safety and efficacy.Post-procedural and eight-month follow-up intravascular ultrasound (IVUS) analysis was available in 61 cases.Volumetric analysis using Simpson's method within the Taxus stent,and cross-sectional analysis at the five sites of the main vessel (MV) and three sites of the side branch (SB) were performed.Impact of the bifurcation angle on stent expansion at the carina was also evaluated.Results Stent expansion in the SB ostium was significantly less in the classical crush group ((53.81±13.51)%) than in the DK crush group ((72.27±11.46)%) (P=-0.04).For the MV,the incidence of incomplete crush was 41.9% in the DK group and 70.0% in the classical group (P=-0.03).The percentage of neointimal area at the ostium had a tendency to be smaller in the DK group compared with the classical group ((16.4±19.2)% vs.(22.8±27.1)%,P=-0.06).The optimal threshold of post-procedural minimum stent area (MSA) to predict follow-up minimum lumen area (MLA) <4.0 mm2 at the SB ostium was 4.55 mm2,yielding an area under the curve of 0.80 (95% confidence interval:0.61 to 0.92).Conclusion Our data suggest that the DK crush technique is associated with improved quality of the final kissing balloon inflation (FKBI) and had smaller optimal cutoff value of post-procedural MSA at the SB ostium.

  10. Mechanical and hydrological characterization of the near-field surrounding excavations in a geologic salt formation

    Energy Technology Data Exchange (ETDEWEB)

    Howard, Clifford L. [Sandia National Laboratories, Albuquerque, NM (United States)

    2014-09-01

    The technical basis for salt disposal of nuclear waste resides in salt’s favorable physical, mechanical and hydrological characteristics. Undisturbed salt formations are impermeable. Upon mining, the salt formation experiences damage in the near-field rock proximal to the mined opening and salt permeability increases dramatically. The volume of rock that has been altered by such damage is called the disturbed rock zone (DRZ).

  11. Review of evaluations of crushing results for the seedbed preparation

    Directory of Open Access Journals (Sweden)

    Siegfried Anisch

    2016-06-01

    Full Text Available For evaluating the work results of tillage operations today only inaccurate parameters are available which cannot be readily measured. Thus, evaluating and comparing the work results of machines and developing suitable sensors are difficult. At the Technical University of Dresden, till 1990, research projects for determining aggregate size composition of soil have been done. Based on this work, this study will show suggestions for measuring, displaying and evaluation of soil crushing results depending on tillage work conditions.

  12. Distribution of Infections and Bacteriological Spectrum in Crush Syndrome

    Directory of Open Access Journals (Sweden)

    Fadime ERSOY DURSUN

    2015-09-01

    Full Text Available OBJECTIVE: This research was designed as a therapeutic and prognostic study to assess the clinical and bacteriological examination findings of crush syndrome patients admitted to our hospital after the Bingol earthquake. MATERIAL and METHODS: A retrospective assessment was carried out on the medical records of the patients with Crush syndrome. Sixteen patients were admitted to the nephrology department after the earthquake. The patients had a mean age of 23 ± 13 years and a mean time spent under rubble of 10.3 ± 7 hours. A total of 16 fasciotomy procedures were carried out in 16 of 11 cases (68%, while 9 of these cases had surgical wounds complicated by infection. RESULTS: Microbiology tests detected bacteriological agents in 88 of 43 (49% specimens collected from 16 of 13 (81% patients. The major bacterial isolates from wound infections included Acinetobacter (46%, Escherichia coli (23% and coagulase negative Staphylococci (14%. Increased length of hospitalization resulted in supervening of secondary bacterial infections. No patients who received treatment died, however a patient surviving a cardiac arrest later developed ischemic encephalopathy. CONCLUSION: Infections are a major problem in crush syndrome, but we suggest that early and vigorous care and appropriate prophylactic antibiotic treatment play a key role in decreased mortality.

  13. The cattle crush strategy: trading opportunities for cattle producers The cattle crush strategy: trading opportunities for cattle producers

    Directory of Open Access Journals (Sweden)

    Nicolás Acevedo Vélez

    2007-04-01

    Full Text Available This research shows that it is possible for U.S. cattle feeders to obtain additional profits if a consistent technical strategy for trading is applied to the cattle crush spread. However, when trading costs are introduced, the likelihood of obtaining profit from trading the crush reduces considerably. It also shows that the level of gains from the cattle crush is related to the month the cattle are marketed. When the crush is used as a hedging strategy it decreases the profit from the feeding operation and reduces the volatility of those returns, helping producers to transfer part of the price risk associated with their production. To provide evidence of these findings, this study utilizes daily prices for 1995 to 2006 of the futures contracts of corn, feeder and live cattle to construct the daily cattle crush spread for two different combinations of futures contracts traded in the Chicago Board of Trade and Chicago Mercantile Exchange. These contract combinations suppose that cattle are fed in feedlots for 170 days before being marketed in April and in October. Two different scenarios are also evaluated using the cattle crush spread: one in which the crush is employed as a pre-placement hedging tool and another in which the crush is used as a post-placement hedging method.En este estudio se muestra que es posible para un productor de ganado de carne en EE.UU obtener utilidades adicionales cuando estrategias de operación en el mercado financiero de futuros de Chicago son utilizadas (i.e. la estrategia “cattle crush”. No obstante, los costos de transacción presentes reduce la probabilidad de obtener utilidades mediante la estrategia de análisis técnico. También se muestra que el nivel de ganancia derivado del uso del “cattle crush” está relacionado con el ciclo ganadero en el cual se realice la operación. Cuando el “cattle crush” se utiliza como alternativa para cubrir riesgo, se reduce considerablemente la volatilidad de los

  14. 'Escher' Rock

    Science.gov (United States)

    2004-01-01

    [figure removed for brevity, see original site] Chemical Changes in 'Endurance' Rocks [figure removed for brevity, see original site] Figure 1 This false-color image taken by NASA's Mars Exploration Rover Opportunity shows a rock dubbed 'Escher' on the southwestern slopes of 'Endurance Crater.' Scientists believe the rock's fractures, which divide the surface into polygons, may have been formed by one of several processes. They may have been caused by the impact that created Endurance Crater, or they might have arisen when water leftover from the rock's formation dried up. A third possibility is that much later, after the rock was formed, and after the crater was created, the rock became wet once again, then dried up and developed cracks. Opportunity has spent the last 14 sols investigating Escher, specifically the target dubbed 'Kirchner,' and other similar rocks with its scientific instruments. This image was taken on sol 208 (Aug. 24, 2004) by the rover's panoramic camera, using the 750-, 530- and 430-nanometer filters. The graph above shows that rocks located deeper into 'Endurance Crater' are chemically altered to a greater degree than rocks located higher up. This chemical alteration is believed to result from exposure to water. Specifically, the graph compares ratios of chemicals between the deep rock dubbed 'Escher,' and the more shallow rock called 'Virginia,' before (red and blue lines) and after (green line) the Mars Exploration Rover Opportunity drilled into the rocks. As the red and blue lines indicate, Escher's levels of chlorine relative to Virginia's went up, and sulfur down, before the rover dug a hole into the rocks. This implies that the surface of Escher has been chemically altered to a greater extent than the surface of Virginia. Scientists are still investigating the role water played in influencing this trend. These data were taken by the rover's alpha particle X-ray spectrometer.

  15. 'Escher' Rock

    Science.gov (United States)

    2004-01-01

    [figure removed for brevity, see original site] Chemical Changes in 'Endurance' Rocks [figure removed for brevity, see original site] Figure 1 This false-color image taken by NASA's Mars Exploration Rover Opportunity shows a rock dubbed 'Escher' on the southwestern slopes of 'Endurance Crater.' Scientists believe the rock's fractures, which divide the surface into polygons, may have been formed by one of several processes. They may have been caused by the impact that created Endurance Crater, or they might have arisen when water leftover from the rock's formation dried up. A third possibility is that much later, after the rock was formed, and after the crater was created, the rock became wet once again, then dried up and developed cracks. Opportunity has spent the last 14 sols investigating Escher, specifically the target dubbed 'Kirchner,' and other similar rocks with its scientific instruments. This image was taken on sol 208 (Aug. 24, 2004) by the rover's panoramic camera, using the 750-, 530- and 430-nanometer filters. The graph above shows that rocks located deeper into 'Endurance Crater' are chemically altered to a greater degree than rocks located higher up. This chemical alteration is believed to result from exposure to water. Specifically, the graph compares ratios of chemicals between the deep rock dubbed 'Escher,' and the more shallow rock called 'Virginia,' before (red and blue lines) and after (green line) the Mars Exploration Rover Opportunity drilled into the rocks. As the red and blue lines indicate, Escher's levels of chlorine relative to Virginia's went up, and sulfur down, before the rover dug a hole into the rocks. This implies that the surface of Escher has been chemically altered to a greater extent than the surface of Virginia. Scientists are still investigating the role water played in influencing this trend. These data were taken by the rover's alpha particle X-ray spectrometer.

  16. 'Earhart' Rock

    Science.gov (United States)

    2004-01-01

    This false-color image taken by NASA's Mars Exploration Rover Opportunity shows a rock informally named 'Earhart' on the lower slopes of 'Endurance Crater.' The rock was named after the pilot Amelia Earhart. Like 'Escher' and other rocks dotting the bottom of Endurance, scientists believe fractures in Earhart could have been formed by one of several processes. They may have been caused by the impact that created Endurance Crater, or they might have arisen when water leftover from the rock's formation dried up. A third possibility is that much later, after the rock was formed, and after the crater was created, the rock became wet once again, then dried up and developed cracks. Rover team members do not have plans to investigate Earhart in detail because it is located across potentially hazardous sandy terrain. This image was taken on sol 219 (Sept. 4) by the rover's panoramic camera, using its 750-, 530- and 430-nanometer filters.

  17. Genesis of Tuzla salt basin

    Science.gov (United States)

    Sušić, Amir; Baraković, Amir; Komatina, Snezana

    2017-04-01

    Salt is condition for the survival of the human race, and holds a special place in the exploitation of mineral resources. It is the only mineral raw material used in direct feeding, and therefore has its own specialty. Salt is a crystalline mineral that is found in seawater, as well as in underground areas where it is formed by deposition of salt sediments. Occurrences of salt water near Tuzla and Gornja Tuzla have been known since the time of the Romans as "ad salinas". The name itself connects Bosnia with its richness in salt, because the word barefoot, which is preserved in a north-Albanian dialect, means a place where boiling salted water are obtained. At the time of the Bosnian kings, these regions are named Soli, which is in connection with occurences of saline sources. Geological studies of rock salt in the area of Tuzla basin are practically began after the annexation of Bosnia and Herzegovina by the Austro-Hungarian Empire, in the period from 1878 to 1918. Geological field work was conducted K. Paul, H. Hefer, E. Tietze and F. Katzer. Monomineral deposit of rock salt Tetima is made of halite and anhydrite mixed with marl belt, while the bay of salt in Tuzla is polymineral and contains a considerable amount of thenardite (Na2SO4) and rare minerals: nortupit, nahkolit, bradleit, probertit, glauberite and others. Both salt deposits were created as a product of chemical sedimentation in the lower Miocene Badenian sediments. The main objective of this paper is to show the genesis of the deposits and the spatial and genetic connection. In addition, genesis of geological research in the areas of Tuzla basin will be presented.

  18. Rock Art

    OpenAIRE

    Huyge, Dirk

    2009-01-01

    Rock art, basically being non-utilitarian, non-textual anthropic markings on natural rock surfaces, was an extremely widespread graphical practice in ancient Egypt. While the apogee of the tradition was definitely the Predynastic Period (mainly fourth millennium BCE), examples date from the late Palaeolithic (c. 15,000 BCE) until the Islamic era. Geographically speaking, “Egyptian” rock art is known from many hundreds of sites along the margins of the Upper Egyptian and Nubian Nile Valley and...

  19. Rock blocks

    OpenAIRE

    Turner, W.

    2007-01-01

    Consider representation theory associated to symmetric groups, or to Hecke algebras in type A, or to q-Schur algebras, or to finite general linear groups in non-describing characteristic. Rock blocks are certain combinatorially defined blocks appearing in such a representation theory, first observed by R. Rouquier. Rock blocks are much more symmetric than general blocks, and every block is derived equivalent to a Rock block. Motivated by a theorem of J. Chuang and R. Kessar in the case of sym...

  20. Numerical Simulation of Blast Vibration and Crack Forming Effect of Rock-Anchored Beam Excavation in Deep Underground Caverns

    Directory of Open Access Journals (Sweden)

    XinPing Li

    2017-01-01

    Full Text Available Aiming at surrounding rock damage induced by dynamic disturbance from blasting excavation of rock-anchored beam in rock mass at moderate or far distance in underground cavern, numerical model of different linear charging density and crustal stress in underground cavern is established by adopting dynamic finite element software based on borehole layout, charging, and rock parameter of the actual situation of a certain hydropower station. Through comparison in vibration velocity, contour surface of rock mass excavation, and the crushing extent of excavated rock mass between calculation result and field monitoring, optimum linear charging density of blast hole is determined. Studies are also conducted on rock mass vibration in moderate or far distance to blasting source, the damage of surrounding rock in near-field to blasting source, and crushing degree of excavated rock mass under various in situ stress conditions. Results indicate that, within certain range of in situ stress, the blasting vibration is independent of in situ stress, while when in situ stress is increasing above certain value, the blasting vibration velocity will be increasing and the damage of surrounding rock and the crushing degree of excavated rock mass will be decreasing.

  1. Common complication of crush injury, but a rare compartment syndrome

    Directory of Open Access Journals (Sweden)

    Shaikh Nissar

    2010-01-01

    Full Text Available Compartment syndrome (CS is a common complication of crush injury but it is rare to find bilateral gluteal compartment syndrome (BGCS. Only six cases of BGCS have been reported in the literature. This syndrome has been reported after crush injury, drug overdose, surgical positioning, and vascular surgery. Apart from CS, crush injury is associated with multi-system adverse effects and these patients are at high risk for renal failure and sepsis. CS patients may present with dehydration; coagulation disorders; elevated creatine phosphokinase and myoglobin levels; hyperkalemia and hypocalcaemia, which may cause life-threatening arrhythmias and therefore need urgent and aggressive therapy. The early goal in these patients is prevention of acute renal failure with aggressive fluid therapy, alkalinization of urine, and forced diuresis. Early treatment of hyperkalemia, antibiotic therapy, immunoprophylaxis, and wound care will minimize the risk of arrhythmias and sepsis. CS must be considered when any patient is diagnosed with crush injury syndrome. CS is defined as elevation of interstitial/intracompartmental pressure, leading to microvascular and myoneural dysfunction and secondary hypoxia; it may cause functional loss or even death if not detected early and treated properly. The increase in pressure in one or all compartments of the gluteal region causes CS with devastating effects on muscle and neurovascular bundles. CS is traditionally diagnosed on the basis of five ′p′s: pain, pallor, paraesthesia, pulselessness and paralysis. Diagnosis of gluteal CS is difficult as the peripheral pulses are preserved and the condition is usually only diagnosed when neurological abnormality is noticed. Diagnosis of CS can be made by direct measurement of the compartment pressure and magnetic resonance imaging or computerized tomography. Gluteal CS is managed by fasciotomy and debridement of necrosed tissue, with secondary closure of fascia. A high index of

  2. Frost resistance of concrete with crushed brick as aggregate

    Directory of Open Access Journals (Sweden)

    Janković Ksenija

    2010-01-01

    Full Text Available The investigation included concrete made by using recycled brick as aggregate. Experimental work included several types of concrete made with the same cement content (385 kg/m3, and same consistency (slump about 1 cm. Recycled brick and combination of natural river aggregate and recycled brick were used as aggregates. The influence of percentage and grain size of crushed brick aggregate on concrete compressive strength, water absorption and frost resistance were observed. On the basis of the results obtained during experimental research, a general conclusion can be drawn that the application of recycled concrete as aggregate can lead to new composites with satisfactory physical-mechanical properties.

  3. 溶浸作用下难溶盐岩力学特性弱化及细观机制研究%MECHANICAL PROPERTY WEAKENING AND THE MESO-MECHANISM OF HARD DISSOLVED SALT ROCK SOAKED IN BRINE

    Institute of Scientific and Technical Information of China (English)

    杨晓琴; 梁卫国; 于艳梅; 张传达; 于伟东; 赵阳升

    2014-01-01

    The internal meso-structure development of rock material contributes a lot to its macroscopic mechanical properties. The mechanical properties weakening mechanism and internal meso-structure development of typical glauberite soaked in brine are studied;and the mechanism of mechanical properties weakening is revealed. It is found that under the actions of swelling and disintegration of hydrophilic mineral in the cement of the rock,the dissolution of sulfate,the ion exchange and the chloride ion erosion damage,etc.,the porosity of glauberite soaked in brine is changed nonlinearly with the solution concentration and soaking time. So,the mechanical properties weakens. The strength weakening coefficient decreases to 0.1-0.2 after the glauberite being soaked in brine for 20 d. Because of the water effect and hydration,the argillaceous content contained in the glauberite would swell or disintegrate. So the deformation of glauberite shows the characteristics of strain softening and ductile from the original brittle behavior. The meso-structure development results also show that the pores in glauberite soaked in brine develop more slowly than that in pure water. The pores development rate in fresh water is several to hundreds of times as that in brine. The porosity of glauberite soaked in water for 48h increases to 16.62%,which is 9 times of that of natural state. And the porosity of glauberite soaked in half saturated solution for 48 h is 3 times of its natural state. However,the porosity of glauberite soaked in saturated solution for the same time has an increase of only 2.8%. The change of porosity is mainly due to dissolution and hydration of sulfate in the glaubetire,the water effect and cement of hydrophilic minerals(mainly glimmerton and smectite contents) swelling. These are definite reasons for the mechanical property weakening of the glauberite. The research results are significant either for study of physico-mechanical properties of the glauberite or for in situ

  4. Art Rocks with Rock Art!

    Science.gov (United States)

    Bickett, Marianne

    2011-01-01

    This article discusses rock art which was the very first "art." Rock art, such as the images created on the stone surfaces of the caves of Lascaux and Altimira, is the true origin of the canvas, paintbrush, and painting media. For there, within caverns deep in the earth, the first artists mixed animal fat, urine, and saliva with powdered minerals…

  5. Art Rocks with Rock Art!

    Science.gov (United States)

    Bickett, Marianne

    2011-01-01

    This article discusses rock art which was the very first "art." Rock art, such as the images created on the stone surfaces of the caves of Lascaux and Altimira, is the true origin of the canvas, paintbrush, and painting media. For there, within caverns deep in the earth, the first artists mixed animal fat, urine, and saliva with powdered minerals…

  6. Expected environments in high-level nuclear waste and spent fuel repositories in salt

    Energy Technology Data Exchange (ETDEWEB)

    Claiborne, H.C.; Rickertsen, L.D., Graham, R.F.

    1980-08-01

    The purpose of this report is to describe the expected environments associated with high-level waste (HLW) and spent fuel (SF) repositories in salt formations. These environments include the thermal, fluid, pressure, brine chemistry, and radiation fields predicted for the repository conceptual designs. In this study, it is assumed that the repository will be a room and pillar mine in a rock-salt formation, with the disposal horizon located approx. 2000 ft (610 m) below the surface of the earth. Canistered waste packages containing HLW in a solid matrix or SF elements are emplaced in vertical holes in the floor of the rooms. The emplacement holes are backfilled with crushed salt or other material and sealed at some later time. Sensitivity studies are presented to show the effect of changing the areal heat load, the canister heat load, the barrier material and thickness, ventilation of the storage room, and adding a second row to the emplacement configuration. The calculated thermal environment is used as input for brine migration calculations. The vapor and gas pressure will gradually attain the lithostatic pressure in a sealed repository. In the unlikely event that an emplacement hole will become sealed in relatively early years, the vapor space pressure was calculated for three scenarios (i.e., no hole closure - no backfill, no hole closure - backfill, and hole closure - no backfill). It was assumed that the gas in the system consisted of air and water vapor in equilibrium with brine. A computer code (REPRESS) was developed assuming that these changes occur slowly (equilibrium conditions). The brine chemical environment is outlined in terms of brine chemistry, corrosion, and compositions. The nuclear radiation environment emphasized in this report is the stored energy that can be released as a result of radiation damage or crystal dislocations within crystal lattices.

  7. Crushed and River-Origin Sands Used as Aggregates in Repair Mortars

    Directory of Open Access Journals (Sweden)

    Maria Stefanidou

    2016-04-01

    Full Text Available The systematic analysis of mortars from monuments or historic buildings and the simultaneous study of the construction environment show that it was common practice to use naturally occurring sand from local rivers or streams for the production of the mortars. There are cases though, mainly on islands, where sands of natural origin were limited, and marine or crushed sands were used possibly after elaboration. In all cases the particle size analysis of old mortar confirms the presence of even distribution of the granules. As regards the design of the repair mortars, there are criteria that should be taken into consideration in order to produce materials with compatible properties. The main properties concerning sands are the grain distribution and maximum size, the color, the content of fines, and soluble salts. The objective of this research is the study of the physical characteristics of the sands such as the sand equivalent, the gradation, the apparent density, the morphology of the grains, their mineralogical composition and the influence of these properties on the behavior of lime mortars, notably the mechanical and physical properties acquired.

  8. Mathematical modeling on multi-stage series crushing ratio distribution based on fuzzy physical programming

    Institute of Scientific and Technical Information of China (English)

    Yu-Long QI; Chen-Chen CAI; Ping-Zhen LANG

    2013-01-01

    Double-layer,multi-roller plate crusher is a new device,that uses a multi-stage series crushing style to break particles,with the crushing ratio distribution directly influencing the machine's performance.Three crushing ratios of 2.25,2.15 and 2.0 1,used for fuzzy physical programming,were determined.The comparison of the optimized result between the double-layer multi-roller plate crusher and a high pressure roll grinder showed that the double-layer multi-roller plate crusher had a better performance,reducing crushing force and wear.

  9. Reconstructions of fingertip and polydigital crush injuries with island and random flaps:a case report

    Institute of Scientific and Technical Information of China (English)

    Krishnakumar Subbaraman; SUN Bing-wei; TAI Ning-zheng; SHEN Jun

    2010-01-01

    @@ A 42-year-old male labourer working in a harbor injured both his hands in a steel rolling device. In the left non-dominant hand the index finger, middle finger and ring finger had crush injury. The right dominant hand had a crush amputation of the tip of the middle finger. In the left hand the ring finger was severely crushed and was not amenable to salvage. The index finger and middle finger was also crushed and had comminuted fractures up to the middle phalanx which was diagnosed by a plain X-ray. The little finger sustained minor soft tissue loss in the fingertip.

  10. Preparation-induced errors in EPR dosimetry of enamel: pre- and post-crushing sensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Haskell, E.H.; Hayes, R.B.; Kenner, G.H. [Utah Univ., Salt Lake City, UT (United States). Radiobiology Div.

    1996-01-01

    Errors in dose estimation as a function of grain size for tooth enamel has been previously shown for beta irradiation after crushing. We tested the effect of gamma radiation applied to specimens before and after crushing. We extend the previous work in that we found that post-crushing irradiation altered the slope of the dose-response curve of the hydroxyapatite signal and produced a grain-size dependent offset. No changes in the slope of the dose-response curve were seen in enamel caps irradiated before crushing.

  11. ROCK ON

    National Research Council Canada - National Science Library

    Thomas Grose

    2014-01-01

    ..., however, was music - especially the high-pitched sounds of pop and rock, which boosted energy output by up to 40 percent. By contrast, classical music's lower pitches barely raised effectiveness. O...

  12. Performance Evaluation Test of the Orbit Screen Model 68A and the Komplet Model 48-25 Rock Crusher

    Science.gov (United States)

    2008-08-01

    screen and on a Komplet Italia , s.r.l., Model 48-25 rock crusher. The test was conducted during August 2008 at a U.S. Army test site in central... Italia , s.r.l., Model 48-25 Rock Crusher.......................................................... 2 2.3 ASV SR-80 Rubber-Tracked Skid-Steer Loader... Italia , s.r.l., Rock Crusher Testing ......................................................................... 16 5.1 Crushing Performance Test

  13. Determination of potassium iodide in table salt

    Directory of Open Access Journals (Sweden)

    Rajković Miloš B.

    2009-01-01

    Full Text Available The samples of table salt bought in Belgrade supermarkets are analysed in this paper. The method of indirect iodometry was used in the process of the analysis, and received results were converted into the content of KI in mg/kg of salt. Beside the content of KI, the content of NaCl was also determined, counted to dry meter and water content, and received results were compared with the requests determined by Regulations of Table Salt Quality Meant for Human Diet and by manufacturers' declaration. Received results show that the volumetric method of indirect iodometry, applied in this analysis, is very reliable for determination of potassium iodine in table salt, because of its high precision and reproducibility of the analysis results. All received results show that the samples of table salt which can be bought in supermarkets are according to the demands given by Regulations. Only one sample (evaporated salt has significantly less mass of KI than it is determined by Regulations, but also by manufacturer's declaration. Measured humidity in the samples of table salt received from sea salt (sample 1 is higher than humidity in the samples received from rock salt as the result of magnesium presence in sea salt, which is hygroscopic material. Although samples 5 and 6 also originate from sea salt, their smaller humidity is the result of additional heating and salt processing. .

  14. Diffusive transport in compacted mixtures of clay and crushed granite

    Energy Technology Data Exchange (ETDEWEB)

    Oscarson, D.W. (AECL Research, Whiteshell Labs., Pinawa, MB (Canada)); Hume, H.B. (AECL Research, Whiteshell Labs., Pinawa, MB (Canada)); Choi, J.W. (Korea Atomic Energy Research Inst., Daejeon (Korea, Republic of))

    1994-01-01

    Diffusion coefficients are important parameters for predicting migration rates of contaminants through earthen barrier materials used in many waste containment strategies. Apparent diffusion coefficients, D, were measured for Tc and I in compacted 1:3 mixtures of Lake Agassiz clay and crushed granite. Technetium-99 and [sup 129]I are two of the most important radioisotopes present in nuclear fuel waste. Lake Agassiz clay is a glacial lake clay composed principally of smectite, illite, quartz and kaolinite. Before being mixed with clay, crushed granite was separated into the following particle size fractions: <150, 150 to 300, 300 to 850, 850 to 2000, and 2000 to 4750 [mu]m. The dry density of the mixes was about 2 Mg/m[sup 3] and they were saturated with a Na-Ca-Cl-dominated synthetic groundwater solution having an effective ionic strength of 220 mol/m[sup 3]. The mean D values (n = 4) for Tc in the mixes ranged from 20 [mu]m[sup 2]/s when the granite particle size was 2000 to 4750 [mu]m to 0.19 [mu]m[sup 2]/s when it was <150 [mu]m. In clay alone, the mean D value was 59 [mu]m[sup 2]/s. The decrease in D with decreasing granite particle size is largely attributed to an increase in the extent of reduction of Tc(VII) to Tc(IV) and its subsequent sorption on Fe(III) oxyhydroxides present in granite. The reductants are probably Fe(II)-bearing minerals, such as magnetite, in granite. The finer the granite particle size, the greater the reactive surface area. For I, clay controls the diffusion process and granite is essentially inert filler. The mean D values for I are about 3 [mu]m[sup 2]/s in all cases. The results show that, depending on the environmental conditions and the nature of the diffusant, crushed granite in compacted clay-based barriers can markedly slow mass transport. (orig.)

  15. Carboxylic and dicarboxylic acids extracted from crushed magnesium oxide single crystals

    Science.gov (United States)

    Freund, F.; Gupta, A. D.; Kumar, D.

    1999-01-01

    Carboxylic and dicarboxylic acids (glycolic, oxalic, malonic and succinic) have been extracted with tetrahydrofuran (THF) and H2O from large synthetic MgO crystals, crushed to a medium fine powder. The extracts were characterized by infrared spectroscopy and 1H-NMR. The THF extracts were derivatized with tert-butyldimethylsilyl (t-BDMS) for GC-MS analysis. A single crystal separated from the extract was used for an x-ray structure analysis, giving the monoclinic unit cell, space group P21/c with ao = 5.543 A, bo = 8.845 A, co = 5.086 A, and beta = 91.9 degrees, consistent with beta-succinic acid, HOOC(CH2)COOH. The amount of extracted acids is estimated to be of the order of 0.1 to 0.5 mg g-1 MgO. The MgO crystals from which these organic acids were extracted grew from the 2860 degrees C hot melt, saturated with CO/CO2 and H2O, thereby incorporating small amounts of the gaseous components to form a solid solution (ss) with MgO. Upon cooling, the ss becomes supersaturated, causing solute carbon and other solute species to segregate not only to the surface but also internally, to dislocations and subgrain boundaries. The organic acids extracted from the MgO crystals after crushing appear to derive from these segregated solutes that formed C-C, C-H and C-O bonds along dislocations and other defects in the MgO structure, leading to entities that can generically be described as (HxCyOz)n-. The processes underlying the formation of these precursors are fundamental in nature and expected to be operational in any minerals, preferentially those with dense structures, that crystallized in H2O-CO2-laden environments. This opens the possibility that common magmatic and metamorphic rocks when weathering at the surface of a tectonically active planet like Earth may be an important source of abiogenically formed complex organic compounds.

  16. Recommendation for the management of crush victims in mass disasters.

    Science.gov (United States)

    Sever, Mehmet Sukru; Vanholder, Raymond

    2012-04-01

    "Recommendations for the management of crush victims in mass disasters" aims to assist medics, paramedics and rescue team members who provide care during disasters. Development of the recommendations followed an explicit process of literature review and, also internet and face-to-face discussions. The chapters cover medical and logistic measures, to be taken both at the disaster field and in the hospitals, to cope with the problems created by a catastrophe. Recommendations were based on retrospective analyses and case reports on past disasters, and also expert judgment or opinion. Since there are no randomized controlled trials, no GRADE approach was used to develop the recommendations, and no strengths of recommendations or levels of evidence are provided.

  17. Phosphate salts

    Science.gov (United States)

    ... levels that are too high, and for preventing kidney stones. They are also taken for treating osteomalacia (often ... But intravenous phosphate salts should not be used. Kidney stones (nephrolithiasis). Taking potassium phosphate by mouth might help ...

  18. Salt cookbook

    CERN Document Server

    Saha, Anirban

    2015-01-01

    If you are a professional associated with system and infrastructure management, looking at automated infrastructure and deployments, then this book is for you. No prior experience of Salt is required.

  19. Effect of crushed sand on mortar and concrete rheology

    Directory of Open Access Journals (Sweden)

    Cabrera, O. A.

    2011-09-01

    Full Text Available This article describes an experimental study conducted on fresh mortars and concretes made with crushed sand. The aim of this research was to assess the effect of aggregate particle shape and surface texture as well as dust content on mortar and concrete rheology. The experimental programme also addressed the impact of angular grains on chemical admixture performance and concrete bleeding. The findings showed that the use of crushed sand induces rheological behaviour that differs from the behaviour observed in natural sand and that superplasticisers can improve this behaviour considerably.

    En el presente trabajo se plantea un estudio experimental del estado fresco de morteros y hormigones con arenas de machaqueo, orientado a la evaluación de la incidencia de la forma y textura superficial de los granos del árido fino y del contenido de polvo sobre la reología de las mezclas. El programa experimental comprendió el estudio del estado fresco de hormigones con arenas con partículas angulares, la influencia de este tipo de partículas sobre la efectividad de los aditivos químicos y la evaluación de la influencia de las características físicas del árido fino sobre la exudación. Los resultados muestran que el empleo de arenas de machaqueo provoca un comportamiento reológico diferente al de hormigones con arenas naturales, y que el efecto de los aditivos superfluidificantes mejora notablemente este comportamiento.

  20. Effect of crush lesion on radiolabelling of ganglioside in rat peripheral nerve

    Energy Technology Data Exchange (ETDEWEB)

    Guzman-Harty, M.; Warner, J.K.; Mancini, M.E.; Pearl, D.K.; Yates, A.J.

    1988-01-01

    Left sciatic nerves of adult male Sprague-Dawley rats were crushed and allowed to recover for 0, 1, 2, 4, 7, or 14 days. At each of these times both L-5 dorsal root ganglia were injected with 100 microCi of (/sup 3/H)glucosamine. Two days later, dorsal root ganglia, lumbosacral trunks, and sciatic nerves were removed bilaterally. The amounts of radiolabelled ganglioside in crushed lumbosacral trunks were consistently higher than in the controls, with the largest difference occurring within 2 days from simultaneous crush and injection to killing (specimens labelled day 0). The largest difference in the amount of radiolabelled ganglioside between crushed and control sciatic nerve (4-9 days from crush to killing) occurred later than that of lumbosacral trunk, but no significant difference occurred within the first 3 days following crush. There was only a slightly higher radioactivity in gangliosides totalled from all three anatomical specimens of crushed than in control nerves. The neutral nonganglioside lipid and acid-precipitable fraction followed patterns of synthesis and accumulation similar to those of the gangliosides. These findings indicate that after nerve crush gangliosides, glucosamine-labelled neutral nonganglioside lipids, and glycoproteins accumulate close to the proximal end of the regenerating axon. This accumulation could serve as a reservoir to increase the ganglioside concentration in the growth cone membrane.

  1. Joining and reinforcing a composite bumper beam and a composite crush can for a vehicle

    Energy Technology Data Exchange (ETDEWEB)

    Berger, Elisabeth; Decker, Leland; Armstrong, Dale; Truskin, James; Pasupuleti, Praveen; Dwarmpudi, Ramesh; Doroudian, Mark

    2017-03-21

    A front bumper beam and crush can (FBCC) system is provided for a vehicle. A bumper beam has an interior surface with a plurality of ribs extending therefrom. The ribs and the interior surface are made of a chopped fiber composite and cooperate to engage a crush can. The chopped fiber composite reinforces the engaging surfaces of the crush can and the interior surface of the bumper beam. The crush can has a tubular body made of a continuous fiber composite. The crush can has outwardly-extending flanges at an end spaced away from the bumper beam. The flanges are at least partially provided with a layer of chopped fiber composite to reinforce a joint between the outwardly-extending flange and the vehicle frame.

  2. Joining and reinforcing a composite bumper beam and a composite crush can for a vehicle

    Science.gov (United States)

    Berger, Elisabeth; Decker, Leland; Armstrong, Dale; Truskin, James; Pasupuleti, Praveen; Dwarmpudi, Ramesh; Doroudian, Mark

    2017-03-21

    A front bumper beam and crush can (FBCC) system is provided for a vehicle. A bumper beam has an interior surface with a plurality of ribs extending therefrom. The ribs and the interior surface are made of a chopped fiber composite and cooperate to engage a crush can. The chopped fiber composite reinforces the engaging surfaces of the crush can and the interior surface of the bumper beam. The crush can has a tubular body made of a continuous fiber composite. The crush can has outwardly-extending flanges at an end spaced away from the bumper beam. The flanges are at least partially provided with a layer of chopped fiber composite to reinforce a joint between the outwardly-extending flange and the vehicle frame.

  3. 'Wopmay' Rock

    Science.gov (United States)

    2004-01-01

    This approximate true-color image taken by NASA's Mars Exploration Rover Opportunity shows an unusual, lumpy rock informally named 'Wopmay' on the lower slopes of 'Endurance Crater.' The rock was named after the Canadian bush pilot Wilfrid Reid 'Wop' May. Like 'Escher' and other rocks dotting the bottom of Endurance, scientists believe the lumps in Wopmay may be related to cracking and alteration processes, possibly caused by exposure to water. The area between intersecting sets of cracks eroded in a way that created the lumpy appearance. Rover team members plan to drive Opportunity over to Wopmay for a closer look in coming sols. This image was taken by the rover's panoramic camera on sol 248 (Oct. 4, 2004), using its 750-, 530- and 480-nanometer filters.

  4. The effect of motorcycle helmet fit on estimating head impact kinematics from residual liner crush.

    Science.gov (United States)

    Bonin, Stephanie J; Gardiner, John C; Onar-Thomas, Arzu; Asfour, Shihab S; Siegmund, Gunter P

    2017-09-01

    Proper helmet fit is important for optimizing head protection during an impact, yet many motorcyclists wear helmets that do not properly fit their heads. The goals of this study are i) to quantify how a mismatch in headform size and motorcycle helmet size affects headform peak acceleration and head injury criteria (HIC), and ii) to determine if peak acceleration, HIC, and impact speed can be estimated from the foam liner's maximum residual crush depth or residual crush volume. Shorty-style helmets (4 sizes of a single model) were tested on instrumented headforms (4 sizes) during linear impacts between 2.0 and 10.5m/s to the forehead region. Helmets were CT scanned to quantify residual crush depth and volume. Separate linear regression models were used to quantify how the response variables (peak acceleration (g), HIC, and impact speed (m/s)) were related to the predictor variables (maximum crush depth (mm), crush volume (cm(3)), and the difference in circumference between the helmet and headform (cm)). Overall, we found that increasingly oversized helmets reduced peak headform acceleration and HIC for a given impact speed for maximum residual crush depths less than 7.9mm and residual crush volume less than 40cm(3). Below these levels of residual crush, we found that peak headform acceleration, HIC, and impact speed can be estimated from a helmet's residual crush. Above these crush thresholds, large variations in headform kinematics are present, possibly related to densification of the foam liner during the impact. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Multi-wire plaque crushing as a novel technique in treating chronic total occlusions

    Institute of Scientific and Technical Information of China (English)

    HAN Ya-ling; WANG Dong-mei; LI Yi; WANG Shou-li; JING Quan-min; MA Ying-yan; WANG Geng; LUAN Bo; WANG Bin; WANG Zhu-lu

    2008-01-01

    Background Failure of balloon catheter passing through the occluded segment accounts for 10%-15% of all procedures during percutaneous coronary intervention(PCI)for chronic total occlusion(CTO).We sought to investigate an original technique for facilitating balloon catheter passing by multi-wire plaque crushing.Methods Between July 2000 and October 2007,152 patients with 164 CTO lesions who had failed balloon passing were treated by multi-wire plaque crushing technique.The main process of this technique was to insert 1 or 2 wires along with the original wire located in the true lumen of CTO lesions after balloon failure for plaque crushing and then to withdraw the crushing wires to get an enlarged lumen inside of the occlusion segment,thus facilitating the balloon passing.Results Both overall lesion and technique success rates were 91.5%(150/164).A total of 211 crushing wires were used during PCI,including 1 crushing wire for 117(71.3%)lesions and 2 crushing wires for 47(28.7%)lesions.Approximately 57.3%(121/211)of all crushing wires were those already used in the same procedure.Technique failure occurred in 14 lesions(8.5%).Technique failure was due to crushing wires entering false lumen(92.9%,13/14)and coronary perforation(7.1%,1/14).Major procedural complications included coronary perforation(1 case)and severe coronary dissection(2 cases),all of which were successfully treated.Conclusions Multi-wire plaque crushing technique is effective in facilitating balloon catheter passing during CTO PCI.It is feasible,economical and relatively safe with a low rate of procedural complications.

  6. Source rock

    OpenAIRE

    Abubakr F. Makky; Mohamed I. El Sayed; Ahmed S. Abu El-Ata; Ibrahim M. Abd El-Gaied; Mohamed I. Abdel-Fattah; Zakaria M. Abd-Allah

    2014-01-01

    West Beni Suef Concession is located at the western part of Beni Suef Basin which is a relatively under-explored basin and lies about 150 km south of Cairo. The major goal of this study is to evaluate the source rock by using different techniques as Rock-Eval pyrolysis, Vitrinite reflectance (%Ro), and well log data of some Cretaceous sequences including Abu Roash (E, F and G members), Kharita and Betty formations. The BasinMod 1D program is used in this study to construct the burial history ...

  7. Rock Paintings.

    Science.gov (United States)

    Jones, Julienne Edwards

    1998-01-01

    Discusses the integration of art and academics in a fifth-grade instructional unit on Native American culture. Describes how students studied Native American pictographs, designed their own pictographs, made their own tools, and created rock paintings of their pictographs using these tools. Provides a list of references on Native American…

  8. Ayers Rock

    Institute of Scientific and Technical Information of China (English)

    王慧茹

    2002-01-01

    Ayers Rock is right in the centre of Australia.It's nearly two thousand kilometres______Sydney.So we flew most of the way.h was rather cloudy______But after we left the mountains behind us, there was hardly a cloud in thesky.

  9. Intellektuaalne rock

    Index Scriptorium Estoniae

    2007-01-01

    Briti laulja-helilooja ja näitleja Toyah Willcox ning Bill Rieflin ansamblist R.E.M. ja Pat Mastelotto King Krimsonist esinevad koos ansamblitega The Humans ja Tuner 25. okt. Tallinnas Rock Cafés ja 27. okt Tartu Jaani kirikus

  10. Intellektuaalne rock

    Index Scriptorium Estoniae

    2007-01-01

    Briti laulja-helilooja ja näitleja Toyah Willcox ning Bill Rieflin ansamblist R.E.M. ja Pat Mastelotto King Krimsonist esinevad koos ansamblitega The Humans ja Tuner 25. okt. Tallinnas Rock Cafés ja 27. okt Tartu Jaani kirikus

  11. Preliminary rock mechanics laboratory: Investigation plan

    Energy Technology Data Exchange (ETDEWEB)

    Oschman, K.P.; Hummeldorf, R.G.; Hume, H.R.; Karakouzian, M.; Vakili, J.E.

    1987-01-01

    This document presents the rationale for rock mechanics laboratory testing (including the supporting analysis and numerical modeling) planned for the site characterization of a nuclear waste repository in salt. This plan first identifies what information is required for regulatory and design purposes, and then presents the rationale for the testing that satisfies the required information needs. A preliminary estimate of the minimum sampling requirements for rock laboratory testing during site characterization is also presented. Periodic revision of this document is planned.

  12. Characteristics of ornamental rocks waste: application of mechanochemical concepts; Caracterizacao de residuos de rochas ornamentais: aplicacao de conceitos mecanoquimicos

    Energy Technology Data Exchange (ETDEWEB)

    Santos, J. dos; Galembeck, F., E-mail: jsquimica@gmail.com [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Instituto de Quimica

    2016-07-01

    Processing of ornamental rocks produces up to 80% weight residues which become an environmental problem. In this work, we analyzed residual powders from cutting and crushing granite Cinza Corumba, to study the influence of mechanical processes in the properties of the residues. The powders were characterized by X-ray diffraction and fluorescence, infrared spectroscopy, scanning electron microscopy, surface area determination and adsorption of methylene blue. The same elements and minerals are found in both powders but the powders formed during crushing contain lubricating oil residues, from the crusher. Particle shapes of the crushed powder (surface area 2.85 m2/g) are more irregular than cut powder (surface area 1.98 m2/g). Adsorption of methylene blue is lighter in the crushed powder than in the cutting powder. Thus, the powders analyzed have different surface properties. (author)

  13. Grain Crush and Its Evolution in Granular Material:a Two-Dimensional Distinct Element Model Approach

    Institute of Scientific and Technical Information of China (English)

    WANG Bao-Shan; SHI Xing-Jue; CHEN Yong; GE Hong-Kui; WONG Teng-Fong

    2004-01-01

    @@ A crush criterion and a simplified post-crush process for spherical grains are introduced into the traditional distinct dement modd (DEM). The crush criterion is based on Hertzian contact, and it indicates a negative rdation between critical force Fcr and radius R via Fcr ∝ R-3/2.

  14. Muscle crush injury of extremity: quantitative elastography with supersonic shear imaging.

    Science.gov (United States)

    Lv, Faqin; Tang, Jie; Luo, Yukun; Ban, Yu; Wu, Rong; Tian, Jiangke; Yu, Tengfei; Xie, Xia; Li, Tanshi

    2012-05-01

    The aim of this study was to determine the characteristic of muscle crush injury at quantitative ultrasonographic elastography using supersonic shear imaging (SSI). Twenty-three New Zealand rabbits underwent crush injury to left hind leg caused by a special balloon cuff device. Conventional ultrasonography and SSI quantitative elastography were performed at both crushed and uncrushed regions of the left hind legs. Quantitative lesion elasticity was measured using the Young's modulus (in kilopascals) at 0.5 h, 2 h, 6 h, 24 h and 72 h after the release of the crushing pressure. Compared with those from the uncrushed regions, both the maximum and mean elasticity values at these time points from the crushed regions were significantly higher (p < 0.001). A receiver operating characteristic (ROC) analysis was employed to assess diagnostic performance. ROC curves showed that extremity crush injury was diagnosed using elasticity value and the greater the elasticity value, the greater the diagnostic value. SSI provides quantitative elasticity measurements, thus, adding complementary information that potentially could help in crush injury characterization with conventional ultrasonography. Crown Copyright © 2012. Published by Elsevier Inc. All rights reserved.

  15. Preconditioning crush increases the survival rate of motor neurons after spinal root avulsion

    Institute of Scientific and Technical Information of China (English)

    Lin Li; Yizhi Zuo; Jianwen He

    2014-01-01

    In a previous study, heat shock protein 27 was persistently upregulated in ventral motor neurons following nerve root avulsion or crush. Here, we examined whether the upregulation of heat shock protein 27 would increase the survival rate of motor neurons. Rats were divided into two groups:an avulsion-only group (avulsion of the L4 lumbar nerve root only) and a crush-avulsion group (the L4 lumbar nerve root was crushed 1 week prior to the avulsion). Immunofluores-cent staining revealed that the survival rate of motor neurons was significantly greater in the crush-avulsion group than in the avulsion-only group, and this difference remained for at least 5 weeks after avulsion. The higher neuronal survival rate may be explained by the upregulation of heat shock protein 27 expression in motor neurons in the crush-avulsion group. Further-more, preconditioning crush greatly attenuated the expression of nitric oxide synthase in the motor neurons. Our ifndings indicate that the neuroprotective action of preconditioning crush is mediated through the upregulation of heat shock protein 27 expression and the attenuation of neuronal nitric oxide synthase upregulation following avulsion.

  16. Segmented Aluminum Honeycomb Characteristics in T-Direction, Dynamic Crush Environments

    Energy Technology Data Exchange (ETDEWEB)

    BATEMAN,VESTA I.; BROWN,FREDERICK A.; NUSSER,MICHAEL A.; SWANSON,LLOYD H.

    2000-08-23

    Thirteen segmented aluminum honeycomb samples (5 in. diameter and 1.5 in. height) have been crushed in an experimental configuration that uses a drop table impact machine. The 38.0 pcf bulk density samples are a unique segmented geometry that allows the samples to be crushed while maintaining a constant cross-sectional area. A crush weight of 175 lb was used to determine the rate sensitivity of the honeycomb's highest strength orientation, T-direction, in a dynamic environment of {approx}50 fps impact velocity. Experiments were conducted for two honeycomb manufacturers and at two temperatures, ambient and +165 F. Independent measurements of the crush force were made with a custom load cell and a force derived from acceleration measurements on the drop table using the Sum of Weighted Accelerations Technique with a Calibrated Force (SWAT-CAL). Normalized stress-strain curves for all thirteen experiments are included and have excellent repeatability. These data are strictly valid for material characteristics in the T orientation because the cross-sectional area of the honeycomb did not change during the crush. The dynamic crush data have a consistent increase in crush strength of {approximately}7--19% as compared to quasi-static data and suggest that dynamic performance may be inferred from static tests. An uncertainty analysis estimates the error in these data is {+-} 11%.

  17. Salt deposits in Los Medanos area, Eddy and Lea counties, New Mexico

    Science.gov (United States)

    Jones, C.L.; with sections on Ground water hydrology, Cooley; and Surficial Geology, Bachman

    1973-01-01

    The salt deposits of Los Medanos area, in Eddy and Lea Counties, southeastern New Mexico, are being considered for possible use as a receptacle for radioactive wastes in a pilot-plant repository. The salt deposits of the area. are in three evaporite formations: the Castile, Salado, and Rustler Formations, in ascending order. The three formations are dominantly anhydrite and rock salt, but some gypsum, potassium ores, carbonate rock, and fine-grained clastic rocks are present. They have combined thicknesses of slightly more than 4,000 feet, of which roughly one-half belongs to the Salado. Both the Castile and the Rustler are-richer in anhydrite-and poorer in rock salt-than the Salado, and they provide this salt-rich formation with considerable Protection from any fluids which might be present in underlying or overlying rocks. The Salado Formation contains many thick seams of rock salt at moderate depths below the surface. The rock salt has a substantial cover of well-consolidated rocks, and it is very little deformed structurally. Certain geological details essential for Waste-storage purposes are unknown or poorly known, and additional study involving drilling is required to identify seams of rock salt suitable for storage purposes and to establish critical details of their chemistry, stratigraphy, and structure.

  18. Pharmacokinetics of lopinavir/ritonavir crushed versus whole tablets in children.

    Science.gov (United States)

    Best, Brookie M; Capparelli, Edmund V; Diep, Huy; Rossi, Steven S; Farrell, Michael J; Williams, Elaine; Lee, Grace; van den Anker, John N; Rakhmanina, Natella

    2011-12-01

    Lopinavir/ritonavir (Kaletra) is first-line therapy for pediatric HIV infection. In clinical practice, Kaletra tablets are occasionally crushed for pediatric administration. This study compared lopinavir/ritonavir exposure between whole and crushed tablets in HIV-infected children. This was a randomized, open-label, cross-over study of pediatric patients taking lopinavir/ritonavir as part of their antiretroviral regimen. Each subject had 2 separate (within 30 days) steady-state 12-hour pharmacokinetic (PK) studies with crushed and whole 200/50 mg lopinavir/ritonavir tablets. PK blood samples were drawn at 0 (predose), 1, 2, 4, 6, 8, and 12 hours postdose. Lopinavir and ritonavir plasma concentrations measured by high-performance liquid chromatography were used to calculate non-compartmental area under the concentration versus time curve (AUC) and clearance. Wilcoxon signed-rank tests compared PK values between crushed and whole tablets. Twelve children, median age of 13 years (10-16 years), took 550/138 mg·m(-2) per day lopinavir/ritonavir divided every 12 hours. The median lopinavir AUC after crushed and whole tablets were 92 mg·hr·L(-1) and 144 mg·hr·L(-1), respectively, with an AUC ratio of 0.55 (P = 0.003). Median ritonavir AUC of crushed and whole tablets were 7 mg·hr·L(-1) and 13.3 mg·hr·L(-1), respectively, with an AUC ratio of 0.53 (P = 0.006). Administration of crushed 200/50 mg lopinavir/ritonavir tablets to children significantly reduced lopinavir and ritonavir exposure with a decrease in AUC by 45% and 47%, respectively. The administration of crushed tablets would require higher doses and therapeutic drug monitoring to ensure adequate lopinavir exposure in patients requiring this practice. The use of crushed lopinavir/ritonavir tablets should be avoided, if possible.

  19. Utilization of crushed clay brick in concrete industry

    Directory of Open Access Journals (Sweden)

    Ali A. Aliabdo

    2014-03-01

    Full Text Available A comprehensive experimental program regarding the use of recycled aggregates produced from demolition of brick buildings is presented. The brick wastes were crushed, sorted and classified into coarse and fine aggregates as well as powder (CBP. The first phase of the research focuses on the effect of incorporating recycled aggregates on physico-mechanical properties of paste, mortar and concrete. Non-traditional tests including X-ray diffraction (XRD, thermo-gravimetric analysis (TGA and micro-structural analysis (MSA were performed. The second phase of the program explores the effect of using recycled aggregates on properties of concrete masonry units. A total of 44 mixtures were utilized throughout the program. Results show cement paste when modified with 25% CBP achieves smaller pore size and lower weight loss under high temperature than reference paste. Furthermore, the use of recycled aggregates reduces the overall unit weight of concrete masonry units. Actually, modified concrete masonry units incorporating recycled aggregates achieve lower unit weight, higher thermal resistance and absorption rate than reference units. Although considerable strength reduction is noticeable by substitution, compressive strength levels meet the Egyptian specifications limitations. Critical replacement ratios are suggested to produce load bearing-concrete masonry units. Based on experimental evidences, it can be stated that the use of recycled aggregate and dust made of clay bricks is promising in many applications where the thermal resistance, cost and environmental aspects are imperative.

  20. Contaminated open fracture and crush injury:a murine model

    Institute of Scientific and Technical Information of China (English)

    Shawn R Gilbert; Justin Camara; Richard Camara; Lynn Duffy; Ken Waites; Hyunki Kim; Kurt Zinn

    2015-01-01

    Modern warfare has caused a large number of severe extremity injuries, many of which become infected. In more recent conflicts, a pattern of co-infection with Acinetobacter baumannii and methicillin-resistant Staphylococcus aureus has emerged. We attempted to recreate this pattern in an animal model to evaluate the role of vascularity in contaminated open fractures. Historically, it has been observed that infected bones frequently appear hypovascular, but vascularity in association with bone infection has not been examined in animal models. Adult rats underwent femur fracture and muscle crush injury followed by stabilization and bacterial contamination with A. baumannii complex and methicillin-resistant Staphylococcus aureus. Vascularity and perfusion were assessed by microCT angiography and SPECT scanning, respectively, at 1, 2 and 4 weeks after injury. Quantitative bacterial cultures were also obtained. Multi-bacterial infections were successfully created, with methicillin-resistant S. aureus predominating. There was overall increase in blood flow to injured limbs that was markedly greater in bacteria-inoculated limbs. Vessel volume was greater in the infected group. Quadriceps atrophy was seen in both groups, but was greater in the infected group. In this animal model, infected open fractures had greater perfusion and vascularity than non-infected limbs.

  1. Failure analysis of crush hammers based on damage fracture energy

    Institute of Scientific and Technical Information of China (English)

    HUANG Jun-ping; ZHOU Hong-yi; BAI Zhan-wei; YIN Yi-zhong

    2009-01-01

    To prolong the life-span of crush hammers in the pyrite concentrate workplace of Ganbazi Coal Preparation Plant of Chongqing Nantong Mining Ltd., we used a progressive damage constitutive model based on the ductile and shear damage fracture energy to analyze the hammer wear failure caused by the impact and abrasion on the hammer surface by pyrite, and carried out simulation analysis with the explicit algorithm on hammer leftovers from the plant during the process of coarser pyrite comminution. The simulation results are consistent with hammer wear failure caused by pyrite impact. Then we proposed corrective measures to prolong hammer life-span. Results of the production test in the Ganbazi Coal Preparation Plant showed that non-clearance hammers can avoid wear erosion, and adding steel bonded tungsten carbides F3002 prolonged the hammer life-span. The effect of austenitic manganese steel work-hardening was not prominent. Therefore, the hammer failure was mainly caused by superficial abrasion instead of fatigue cracks appearing when grains acted on the hardening layer.

  2. Rat Sciatic Nerve Crush Injury and Recovery Tracked by Plantar Test and Immunohistochemistry Analysis

    OpenAIRE

    Pavić, Roman; Pavić, Michele L.; Tvrdeić, Ante; Tot, Ozana K.; Heffer, Marija

    2011-01-01

    An experimental crush injury to the sciatic nerve, with a crush force of 49.2 N (pressure p=1.98x108 Pa), was inflicted in 30 male rats (Wistar). A control group (sham), with the same number of rats, was also operated upon exactly as the experimental group but without the crush injury. We tested the sensory and motor recovery of the sciatic nerve with Hargreaves method, using an apparatus from Ugo Basile, Italy. Testing was continued for both legs of each rat, injured and uninjured, starting ...

  3. A benchmark study of procedures for analysis of axial crushing of bulbous bows

    DEFF Research Database (Denmark)

    Yamada, Yasuhira; Pedersen, Preben Terndrup

    2008-01-01

    Simplified methods to estimate mean axial crushing forces of plated structures are reviewed and applied to a series of experimental results for axial crushing of large-scale bulbous bow models. Methods based on intersection unit elements such as L-, T- and X-type elements as well as methods based...... on plate unit elements are employed in the analyses. The crushing forces and the total absorbed energy obtained by the simplified analyses are compared with those obtained from large-scale bulbous bow experiments. The accuracy and the applicability of these methods are discussed in detail....

  4. Discrete modelling of rock-fill: Application to dams; Modelisation discrete des enrochements: Application aux barrages

    Energy Technology Data Exchange (ETDEWEB)

    Deluzarche, R.

    2004-12-15

    In this study, a discrete numerical model for rock-fill is built up and validated. This model is based upon the definition of bidimensional clusters that can break in different ways. The resistance of the inner bonds of the clusters are calibrated by reproducing the size-dependant resistance of rock blocks submitted to crushing tests. Numerical simulations of laboratory tests are performed on samples made of the different clusters. Tests on crushable clusters emphasize the utmost importance of particle crushing on the behaviour. A dam is modelled. The role of the placed-rock face on the stabilisation is underlined. The deformation of the dam during reservoir filling, as well as its good seismic behaviour is well reproduced by the model. The model makes it possible to show the influence of particle breakage on the settlements. (author)

  5. The Use of Steel Works Crushed Slag (Lidonit in the Preparation of Asphalt Mixtures

    Directory of Open Access Journals (Sweden)

    Gh. Gugiuman

    2004-01-01

    Full Text Available The high costs of the quarry crushed aggregates (producer costs to which additional railroad transport costs are taken into account result in the fact that at large distance away from quarry lesser amounts of chippings and crushing sands are provided only. The initiation of the crushed aggregates production manufactured out of steelworks crushed slag. Lidonit, at a competitive delivering price, has led to the first series of laboratory tests. In the first stage two asphalt concrete mixtures were made in cube-shaped and cylinder-shaped (Marshall test-tubes on which physical and mechanical characteristic values are determined. The results of these first tests outlined the real opportunity of using these products in supplying the roads and streets with asphalt mix for pavements.

  6. The Tree-Crushing Program on the Kenai National Moose Range

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report outlines the tree-crushing program at Kenai National Wildlife Refuge. Efforts to control vegetation on Kenai National Wildlife Refuge for the benefit of...

  7. Comparison of nerve graft integration after segmentar resection versus epineural burying in crushed rat sciatic nerves

    Directory of Open Access Journals (Sweden)

    Cunha Marco Túlio Rodrigues da

    1997-01-01

    Full Text Available The aim of the present paper is to compare and correlate the take of nerve segments in a severely crushed nerve. Forty adult Wistar rats had their right sciatic nerve by a "Péan-Murphy" forceps for 40 minutes. In Group 1 (n=20, a segmentar serection in the crushed sciatic nerve was made. A sural nerve segment from the opposite hindpaw was placed in the gap. In Group 2 (n=20, a lontudinal insision in the epineurium of the lesioned sciatic nerve was made. A sural nerve segment was buried underneath the epineurium. The crushed sciatic nerves undergone Wallerian degeneration and endoneurial fibrosis. Sciatic nerves from Group 2 had significant better histological aspects than those from Group 1. Sural nerve grafts presented better degrees of regeneration than crushed sciatic nerves. Sural nerve grafts from Group 2 (burying method integrated as well as those from Group 1 (segmentar resection.

  8. Schematic designs for penetration seals for a reference repository in bedded salt

    Energy Technology Data Exchange (ETDEWEB)

    Kelsall, P.C.; Case, J.B.; Meyer, D.; Coons, W.E.

    1982-11-01

    The isolation of radioactive wastes in geologic repositories requires that man-made penetrations such as shafts, tunnels, or boreholes are adequately sealed. This report describes schematic seal designs for a repository in bedded salt referenced to the straitigraphy of southeastern New Mexico. The designs are presented for extensive peer review and will be updated as site-specific conceptual designs when a site for a repository in salt has been selected. The principal material used in the seal system is crushed salt obtained from excavating the repository. It is anticipated that crushed salt will consolidate as the repository rooms creep close to the degree that mechanical and hydrologic properties will eventually match those of undisturbed, intact salt. For southeastern New Mexico salt, analyses indicate that this process will require approximately 1000 years for a seal located at the base of one of the repository shafts (where there is little increase in temperature due to waste emplacement) and approximately 400 years for a seal located in an access tunnel within the repository. Bulkheads composed of contrete or salt bricks are also included in the seal system as components which will have low permeability during the period required for salt consolidation.

  9. Freshly Crushed Garlic is a Superior Cardioprotective Agent than Processed Garlic

    OpenAIRE

    2009-01-01

    In this study, we compared the cardioprotective effects of freshly crushed garlic vis-à-vis that of processed garlic. Two groups of rats were gavaged with respective garlic preparations while the control group received vehicle only. After 30 days, all the rats were sacrificed and isolated hearts were subjected to 30 min ischemia followed by 2 h of reperfusion. Both the garlic preparations provided cardioprotection, but superior cardiac performance was noticed for those fed with freshly crushe...

  10. Severe crush syndrome complicated with acute pancreatitis: a case report and review of the literatures

    Institute of Scientific and Technical Information of China (English)

    LIU Fang; ZHANG Ling; FU Ping; SU Bai-hai; CHEN Xiao-lei; LIU Ling; CHEN Wei-xia; TAO Ye; HUANG Song-min

    2009-01-01

    @@ Earthquake is one of the most catastrophic natural disasters. As we know, crush syndrome is the second most frequent cause of mortality after the direct impact of trauma.~(1-3) It is a serious clinical case that develops among casualties of earthquakes or other catastrophic events that may also result in a variety of ensuing uncommon complications. Cases of crush syndrome complicated with acute pancreatitis (AP) following the earthquakes are seldom reported.

  11. Freshly Crushed Garlic is a Superior Cardioprotective Agent than Processed Garlic

    OpenAIRE

    Mukherjee, Subhendu; Lekli, Istvan; Goswami, Shyamal; Das, Dipak K.

    2009-01-01

    In this study, we compared the cardioprotective effects of freshly crushed garlic vis-à-vis that of processed garlic. Two groups of rats were gavaged with respective garlic preparations while the control group received vehicle only. After 30 days, all the rats were sacrificed and isolated hearts were subjected to 30 min ischemia followed by 2 h of reperfusion. Both the garlic preparations provided cardioprotection, but superior cardiac performance was noticed for those fed with freshly crushe...

  12. Estrogen Effects after a Crush Muscle Injury and Acute Exposure to Hypobaric Hypoxia

    Science.gov (United States)

    2015-03-01

    et al. Intermittent hypobaric hypoxia increases the ability of neutrophils to generate superoxide anion in humans. Clin Exp Pharmacol Physiol. 2003...AFRL-SA-WP-TR-2015-0007 Estrogen Effects after a Crush Muscle Injury and Acute Exposure to Hypobaric Hypoxia Dr. Barbara St...after a Crush Muscle Injury and Acute Exposure to Hypobaric Hypoxia 5a. CONTRACT NUMBER FA7014-10-2-0001 5b. GRANT NUMBER 5c. PROGRAM

  13. Investigation of Usability as Aggregate of Different Originated Rocks

    Science.gov (United States)

    Başpinar Tuncay, Ebru; Kilinçarslan, Şemsettin; Yağmurlu, Fuzuli

    2016-10-01

    The general properties of aggregate can determine the performance and durability of the concrete. In this study, mineralogical, petrographic, mechanical, physical and chemical properties of the rock samples of different origin (limestone, recrystallized limestone, dolomite, sand and gravel, tephra-phonolite, trachybasalt) were determined. Samples were obtained from different origin rocks units and they have been classified in three different sizes of aggregate with crushing and screening method. Grading, classification of particle, loose bulk density, water absorption ratio, flakiness index, coefficient of Los Angeles, resistance to freeze-loosening and alkali-silica reaction of aggregates and organic matter determination has been determined. The rocks have been investigated in compliance with the relevant standards. Trachybasalt and dolomite have higher particle density than other rocks. In addition, strength and flexural strength of these rocks are higher than other rocks. Tephra-phonolite has the lowest water absorption rate. At the same time resistance to freeze loosening of Tephra- phonolite is lower than the other rocks. Resistance to fragmentation and the resistance to wear of all of rocks are quite high. Sand and gravel, tephra-phonolite and trachybasalt are evaluated in terms of alkali-silica reaction. Sand and gravel are more reactive than the other aggregates. Organic matter content of the aggregates is low for the quality of aggregate. Also high correlation between some properties of aggregates was observed. For example, high correlation between compressive strength and flexural strength, water absorption and porosity, resistance to fragmentation and the resistance to ware (Micro-Deval).

  14. THE ROLE OF SATELLITE CELLS IN CRUSH INJURY OF RAT SKELETON MUSCLE

    Directory of Open Access Journals (Sweden)

    DilekBURUKOĞLU

    2013-02-01

    Full Text Available The crush type of injury in rat skeletal muscle is often used in tissue degeneration and regeneration. After crush injury muscle tissue begins to regenerate. In this process, it is accepted that satellite cells play an important role which are very sensitive to muscle injury. The aim of this microscopic study was to examine role of satellite cells in muscle regeneration in crush injury. This research was done the department of Histology&Embryology in Eskişehir Osmangazi University in 2008. Ethic approval of this study has been received. During the study, the whole essential and ethics conditionshave been done. In the study 36 Spraque-Dawley rats were used. The rats were separated into 5 groups as test and control groups. Crush type of injury has been applied on muscles of right hind extremitiesof testing group rats by applying 3.5 kg of weight for 6 hours. In according to testing periods rats were anaesthetized intraperitoneally with ketamine 30mg/kg + xylazine 10mg/kg and sacrificied 3, 7, 14 and 21-day intervals. After crush injury, increased satellite cells were particularly observed on day 7. Alsosignificant increased of satellite cells and regenerated myofibrils were detected on day 14. However, satellite cells were seen on day-21 were similar to control group. In crush injuries, number of satellitecells were markedly increased and actively involved into regeneration process of the skeleton muscle.

  15. Freshly crushed garlic is a superior cardioprotective agent than processed garlic.

    Science.gov (United States)

    Mukherjee, Subhendu; Lekli, Istvan; Goswami, Shyamal; Das, Dipak K

    2009-08-12

    In this study, we compared the cardioprotective effects of freshly crushed garlic vis-a-vis that of processed garlic. Two groups of rats were gavaged with respective garlic preparations while the control group received vehicle only. After 30 days, all of the rats were sacrificed and isolated the hearts were subjected to 30 min ischemia followed by 2 h of reperfusion. Both of the garlic preparations provided cardioprotection, but superior cardiac performance was noticed for those fed with freshly crushed garlic. Consistent with these results, the freshly crushed garlic group displayed significantly greater phosphorylation of antiapoptotic ERK1/2 proteins, reduced Bax/Bcl-2 ratio, and reduced phosphorylation of proapoptotic p-38MAPK and JNK. Moreover, the survival signaling network consisting of Akt-FoxO1 was increased in the freshly crushed garlic treated hearts. Freshly crushed garlic, but not the processed garlic, showed enhanced redox signaling as evident by increased level of p65 subunit of NFkappaB, Nrf2, and enhanced GLUT 4, PPARalpha, and PPARdelta. The results thus show that although both freshly crushed garlic and processed garlic provide cardioprotection, the former has additional cardioprotective properties presumably due to the presence of H2S.

  16. Morphology does not predict performance: jaw curvature and prey crushing in durophagous stingrays.

    Science.gov (United States)

    Kolmann, Matthew A; Crofts, Stephanie B; Dean, Mason N; Summers, Adam P; Lovejoy, Nathan R

    2015-12-01

    All stingrays in the family Myliobatidae are durophagous, consuming bivalves and gastropods, as well as decapod crustaceans. Durophagous rays have rigid jaws, flat teeth that interlock to form pavement-like tooth plates, and large muscles that generate bite forces capable of fracturing stiff biological composites (e.g. mollusk shell). The relative proportion of different prey types in the diet of durophagous rays varies between genera, with some stingray species specializing on particular mollusk taxa, while others are generalists. The tooth plate module provides a curved occlusal surface on which prey is crushed, and this curvature differs significantly among myliobatids. We measured the effect of jaw curvature on prey-crushing success in durophagous stingrays. We milled aluminum replica jaws rendered from computed tomography scans, and crushed live mollusks, three-dimensionally printed gastropod shells, and ceramic tubes with these fabricated jaws. Our analysis of prey items indicate that gastropods were consistently more difficult to crush than bivalves (i.e. were stiffer), but that mussels require the greatest work-to-fracture. We found that replica shells can provide an important proxy for investigations of failure mechanics. We also found little difference in crushing performance between jaw shapes, suggesting that disparate jaws are equally suited for processing different types of shelled prey. Thus, durophagous stingrays exhibit a many-to-one mapping of jaw morphology to mollusk crushing performance. © 2015. Published by The Company of Biologists Ltd.

  17. Significant geological engineering assessment salt massif, using them as a medium for the construction of underground objects for different purposes

    Directory of Open Access Journals (Sweden)

    Bosevskaja L,P.

    2010-06-01

    Full Text Available At present time rock salt bodies are considered to be not only an object for mining operations (rock salt but also a favorable geological environment for allocating different under-ground objects. Yet to this day there is no generally accepted synergetic system of engineering-geological estimation of rock salt bodies. In the paper given they propose underlying principles of system approach to solving issues of keeping equilibrium system under creating man-caused cavities of different purposes in rock salt bodies.

  18. Controlling the processes of impact interaction of a tool with rocks in the region of spasmodic destruction frequencies

    Energy Technology Data Exchange (ETDEWEB)

    Dzidziguri, A.A.; Sepiashvili, A.D.; Yamanidze, T.Sh.

    1983-01-01

    A working hypothesis is described which made it possible to take into consideration the wave processes occurring in the drilling tool, and the discrete nature of crushing of rocks in limits of a single impact. A mathematical model is given for the process of impact interaction of the drilling tool with the rock. It is indicated that the nonlinear elastic link with assigned rigid characteristics under conditions of single-frequency harmonic effect result in excitation of the highest odd harmonics. It follows from this that the contact region which is a nonlinear fluctuating contour in the same way as the wave reflector can create with definite conditions polyresonance modes of oscillations of the working end of the drilling tool, and promote intensification of the processes of spasmodic crushing of rocks in systems of direct impact or impact through the drilling machine. Practical realization of the optimal nonlinear elastic bond in the region of contact of crushing tool with the rock is possible by optimizing form, dimensions and elastic properties of the crushing tool.

  19. Magnetic resonance imaging evaluation of acute crush injury of rabbit sciatic nerve: correlation with histology

    Energy Technology Data Exchange (ETDEWEB)

    Li, X. [Dept. of Radiology, The First Affiliated Hospital of Guangzhou Medical College, Guangzhou (China)], E-mail: xinchunli@163.com; Shen, J.; Chen, J.; Wang, X.; Liu, Q.; Liang, B. [Dept. of Radiology, The Second Affiliated Hospital of Sun Yat-Sen Univ., Guangzhou (China)

    2008-06-15

    To investigate the relation between the quantitative assessment of magnetic resonance imaging (MRI) features and the correlation with histology and functional recovery by using the rabbit sciatic nerve crush model. In New Zealand, 32 rabbits were randomly divided into 2 groups (group A and B); all rabbits underwent crushing injury of their left sciatic nerve. In group A (n = 16), the sciatic nerves were crushed by using microvessel clamps with a strength of 3.61 kg. In group B (n = 16), the sciatic nerves were crushed with a strength of 10.50 kg. Right sciatic nerves were served as controls. Serial MRI of both hind limbs in each rabbit was performed before and at the time point of 1, 2, 4, and 8 weeks after crushed injury. The MRI protocol included T1-weighted spin-echo (T1WI), 3 dimension turbo spin-echo T2-weighted (3DT2WI), T2-weighted turbo spin-echo images with spectral presaturation with inversion recovery (T2WI/SPIR), balanced fast-field echo (B-FFE) and short-time inversion recovery (STIR) sequences. The coronal image of the sciatic nerve was obtained. The nerve and muscle signal ratio (SIR) on each sequence was measured. The function recovery was observed and pathological examination was performed at each time point. A signal intensity increase of the distal segment of crushed sciatic nerves was found on 3DT2WI, T2WI/SP1R, B-FFE, and STIR, but not on T,WI images. Of 32 crushed nerves, 30 nerves showed high signal intensity. The correct diagnostic rate was 93.75% with false negative-positive of 6.25%. The SIR of the crushed sciatic nerve at distal portion was higher than those of the control nerves; there was a statistically significant difference (P < 0.001). The SIR of the distal portion of crushed nerves was higher than that of the proximal nerve portion; there was a statistically significant difference (P < 0.001). Whereas, the SIR at proximal nerve portions of crushed nerve was similar to control nerves (P > 0.05). The SIR between group A and group B

  20. The Protective Role of Mecobalamin Following Optic Nerve Crush in Adult Rats

    Institute of Scientific and Technical Information of China (English)

    Xiangmei Kong; Xinghuai Sun; Jinjun Zhang

    2004-01-01

    Purpose: To evaluate the potential for Mecobalamin as a neuroprotective agent in optic nerve crush injury.Methods: Twenty-four adult Sprague-Dawley rats were randomly divided into four groups.One group acted as normal controls, while in the other three groups the right eye was subjected to optic nerve crush injury. Of the three crush injury groups one group received no treatment, while the other two groups received intramuscular injections of VitaminB12 or Mecobalamin (10μg) immediately after crush injury and then every two days. All the rats were sacrificed one month post-treatment, and the eyes attached with optic nerves were removed for histology. The morphological changes of optic nerve axons and retinal ganglion cells (RGCs) were assessed under light microscope (LM) and transmission electromicroscope (TEM). The numbers of axons and RGCs were counted.Results: In this study we demonstrate the potential for Mecobalamin as a neuroprotective agent following optic nerve crush injury. We show here that the axons of optic nerves were loose in structure or destroyed. The mitochondria of the RGCs was swollen, and the Nissel body was less evident after the crush injury. Moreover, the number of axons and RGCs was significantly reduced (P < 0.001). However, these changes were less dramatic after the Mecobalamin-treatment. More axons and RGCs were remained in the group than those in the untreated injury group (P = 0.010 and 0.003 respectively), and those in the VitaminB12-treated group (P=0.037 and 0.035 respectively). More significantly, there were newly formed axons found in the Mecobalamin-treated group.Conclusions: Optic nerve crush injury in rats causes the loss of the axons and RGCs but this may be ameliorated by treatment with Mecobalamin.

  1. Reduced Renshaw Recurrent Inhibition after Neonatal Sciatic Nerve Crush in Rats

    Directory of Open Access Journals (Sweden)

    Liang Shu

    2014-01-01

    Full Text Available Renshaw recurrent inhibition (RI plays an important gated role in spinal motion circuit. Peripheral nerve injury is a common disease in clinic. Our current research was designed to investigate the change of the recurrent inhibitory function in the spinal cord after the peripheral nerve crush injury in neonatal rat. Sciatic nerve crush was performed on 5-day-old rat puppies and the recurrent inhibition between lateral gastrocnemius-soleus (LG-S and medial gastrocnemius (MG motor pools was assessed by conditioning monosynaptic reflexes (MSR elicited from the sectioned dorsal roots and recorded either from the LG-S and MG nerves by antidromic stimulation of the synergist muscle nerve. Our results demonstrated that the MSR recorded from both LG-S or MG nerves had larger amplitude and longer latency after neonatal sciatic nerve crush. The RI in both LG-S and MG motoneuron pools was significantly reduced to virtual loss (15–20% of the normal RI size even after a long recovery period upto 30 weeks after nerve crush. Further, the degree of the RI reduction after tibial nerve crush was much less than that after sciatic nerve crush indicatig that the neuron-muscle disconnection time is vital to the recovery of the spinal neuronal circuit function during reinnervation. In addition, sciatic nerve crush injury did not cause any spinal motor neuron loss but severally damaged peripheral muscle structure and function. In conclusion, our results suggest that peripheral nerve injury during neonatal early development period would cause a more sever spinal cord inhibitory circuit damage, particularly to the Renshaw recurrent inhibition pathway, which might be the target of neuroregeneration therapy.

  2. Crushed Limestone Dust Valorization for Eco Friendly non Fired Wall Tiles

    Directory of Open Access Journals (Sweden)

    Wangrakdiskul Ubolrat

    2016-01-01

    Full Text Available Utilizing crushed limestone dust; the by-product of crushing limestone plant for producing non-fired wall tiles is the objective of this research. The main raw materials of non-fired wall tiles consist of laterite soil, fluvial sand and Portland cement. The crushed limestone dust has been used as the substitute material of non-fired wall tiles for enhancing their bending strength. In this experiment, four groups of formulas have been constructed. Firstly, crushed limestone dust has been mixed into the basic formula for substitution of laterite soil. Secondly, crushed limestone dust has been used for substitution to river soil of the basic formula. Thirdly, it has been substituted to Portland cement in the basic formula. Finally, the best formulas of the first three groups has been selected and mixed up to make the new formulas. After mixing the raw materials of selected formula, forming specimens by uni-axial pressing at 100 bar has been performed. Then, they have been aged for 1 week at the room temperature. After that, testing the specimens’ properties has been carried out. They are bending strength and water absorption which comparing with Thailand Industrial Standard (TIS 614-2529. The experimental results show that adding the crushed limestone dust to the basic composition has an effect on the bending strength and water absorption. The compositions of the best formula are laterite soil 55%, fluvial sand 7.5%, Portland cement 22.5%, and crushed limestone dust 15%. It gives the bending strength by 2.32 MPa, water absorption 3.20%. The water absorption property can pass the TIS standard, but bending strength could not pass. The estimated cost of raw materials is 0.09065 THB/100 g.

  3. Sensitivity of storage field performance to geologic and cavern design parameters in salt domes.

    Energy Technology Data Exchange (ETDEWEB)

    Ehgartner, Brian L. (Sandia National Laboratories, Albuquerque, NM); Park, Byoung Yoon

    2009-03-01

    A sensitivity study was performed utilizing a three dimensional finite element model to assess allowable cavern field sizes for strategic petroleum reserve salt domes. A potential exists for tensile fracturing and dilatancy damage to salt that can compromise the integrity of a cavern field in situations where high extraction ratios exist. The effects of salt creep rate, depth of salt dome top, dome size, caprock thickness, elastic moduli of caprock and surrounding rock, lateral stress ratio of surrounding rock, cavern size, depth of cavern, and number of caverns are examined numerically. As a result, a correlation table between the parameters and the impact on the performance of storage field was established. In general, slower salt creep rates, deeper depth of salt dome top, larger elastic moduli of caprock and surrounding rock, and a smaller radius of cavern are better for structural performance of the salt dome.

  4. Multiphase CFD modelling of water evaporation and salt precipitation in micro-pores

    NARCIS (Netherlands)

    Twerda, A.; O’Mahoney, T.S.D.; Velthuis, J.F.M.

    2014-01-01

    The precipitation of salt in porous reservoir rocks is an impairment to gas production, particularly in mature fields. Mitigation is typically achieved with regular water washes which dissolve the deposited salt and transport it in the water phase. However, since the process of salt precipitation is

  5. The origin of groundwater salinity in granitic rocks: identification and characterisation of chloride sources; Origine de la salinite des eaux souterraines en milieu granitique: identification et caracterisation des sources de chlorure

    Energy Technology Data Exchange (ETDEWEB)

    Savoye, S.

    1998-04-29

    Hydrogeological research in crystalline rocks, developed either in geothermics or in feasibility studies for geological disposal of radioactive waste, points out a wide range of chloride contents in associated groundwaters. The aim of this dissertation is to identify the possible origins of chloride in groundwaters within different geological conditions. The three possible chloride reservoirs (chloride-bearing minerals, fluid inclusions, micro-porosity) located in rock have been characterised by studying samples from eight granitic sites with different technical approaches (electronic microbeam, alkaline fusion, micro-thermometry, crush-leaching, diffusion experiment). Firstly, this allows the definition of a new typology of the sites, by considering not only hydrogeological features but also occurrence of salt-rich fluid inclusions with sedimentary origin. Secondly, the use of tracers (such as Cl/Br ratio, {delta}{sup 37}Cl) and mass balance calculations shows that the contribution of fluid inclusions trapped in quartz and chloride-bearing minerals cannot account for the high salinity of groundwater. In this case, the chloride origin could be of sedimentary type. Chloride would be stored in micro-porosity and in fluid inclusions trapped in carbonates. Thirdly, we have pointed out the importance of micro-porosity, acting more as a sieve and a buffer than as a source. Finally, we have shown that the low salinity of groundwaters has not always an internal origin. (author) 187 refs.

  6. The spatiotemporal localization of JAM-C following sciatic nerve crush in adult rats.

    Science.gov (United States)

    Avari, Parizad; Huang, Wenlong; Averill, Sharon; Colom, Bartomeu; Imhof, Beat A; Nourshargh, Sussan; Priestley, John V

    2012-07-01

    JAM-C is a junctional adhesion molecule, enriched at tight junctions on endothelial and epithelial cells, and also localized to Schwann cells at junctions between adjoining myelin end loops. The role of JAM-C following peripheral nerve injury (PNI) is currently unknown. We examined the localization of JAM-C after sciatic nerve crush injury in adult rats. JAM-C immunoreactivity was present in paranodes and incisures in sham surgery control nerve, but distal to the crush injury significantly decreased at three and 14 days. JAM-C was re-expressed at 28 days and, by 56 days, was significantly increased in the distal nerve compared to controls. In a 7-mm length of sciatic nerve sampled distal to the crush site, the densities of JAM-C immunoreactive paranodes increased in the distal direction. Conversely, the densities of JAM-C immunoreactive incisures were highest immediately distal to the crush site and decreased in the more distal direction. Further analysis revealed a strong correlation between JAM-C localization and remyelination. Fifty-six days after crush injury, greater densities of JAM-C paranodes were seen compared to the nodal marker jacalin, suggesting that paranodal JAM-C precedes node formation. Our data are the first to demonstrate a potential role of JAM-C in remyelination after PNI.

  7. Lectures on ceramics experimenting technologies. Crushing; Ceramics jikken gijutsu koza. Funsai

    Energy Technology Data Exchange (ETDEWEB)

    Masaki, H. [Toyota Central Research and Development Labs., Inc., Aichi (Japan)

    1997-04-01

    This paper explains a laboratory process for ceramics crushing. Crushing is performed to obtain powder particles having desired size, shape and grain size distribution for the purpose of improving their formability and sinterability. Crushing devices and methods may vary according to these requirements. A ball mill is suitable for obtaining wide grain size distribution, and a vibration mill and a media stirring mill for obtaining narrow grain size distribution. However, an easily cleanable and inexpensive device suits better in a study stage because what is require for a study is mainly property experiments. Calcinated BaTiO3, for example, is first crushed to several mm or smaller with the dry method by using a mortar and a pestle. Then, it is pulverized to sub-microns with the wet method by using a ball mill, a vibration mill or a media stirring mill. Particle size and its distribution may be measured to evaluate particles before and after the crushing. A sieve can classify particles relatively easily if their size is 50 {mu} m or larger. A particle size distribution measuring device can measure sizes ranging from sub-microns to several hundred {mu}m continuously in a short time. Specific surface area is measured generally by using the nitrogen gas adsorption BET method. 8 refs., 4 figs., 3 tabs.

  8. Study on characteristics of printed circuit board liberation and its crushed products.

    Science.gov (United States)

    Quan, Cui; Li, Aimin; Gao, Ningbo

    2012-11-01

    Recycling printed circuit board waste (PCBW) waste is a hot issue of environmental protection and resource recycling. Mechanical and thermo-chemical methods are two traditional recycling processes for PCBW. In the present research, a two-step crushing process combined with a coarse-crushing step and a fine-pulverizing step was adopted, and then the crushed products were classified into seven different fractions with a standard sieve. The liberation situation and particle shape in different size fractions were observed. Properties of different size fractions, such as heating value, thermogravimetric, proximate, ultimate and chemical analysis were determined. The Rosin-Rammler model was applied to analyze the particle size distribution of crushed material. The results indicated that complete liberation of metals from the PCBW was achieved at a size less than 0.59 mm, but the nonmetal particle in the smaller-than-0.15 mm fraction is liable to aggregate. Copper was the most prominent metal in PCBW and mainly enriched in the 0.42-0.25 mm particle size. The Rosin-Rammler equation adequately fit particle size distribution data of crushed PCBW with a correlation coefficient of 0.9810. The results of heating value and proximate analysis revealed that the PCBW had a low heating value and high ash content. The combustion and pyrolysis process of PCBW was different and there was an obvious oxidation peak of Cu in combustion runs.

  9. Adaptation of oral medication in people institutionalized in nursing homes for whom medication is crushed: The ADECUA Study

    OpenAIRE

    2016-01-01

    Purpose: To evaluate the effect of pharmacist interventions in the adaptation of pharmaceutical forms in elders institutionalized in nursing homes whose medicines are crushed, which may have a clinical relevance. Methods: Quasi-experimental, multicenter, transversal and prospective study carried out in 10 nursing homes. Subjects for whom drugs were being crushed were identified. Their treatments were reviewed in order to identify drugs that should not be crushed. In these cases,...

  10. CERN Rocks

    CERN Document Server

    2004-01-01

    The 15th CERN Hardronic Festival took place on 17 July on the terrace of Rest 3 (Prévessin). Over 1000 people, from CERN and other International Organizations, came to enjoy the warm summer night, and to watch the best of the World's High Energy music. Jazz, rock, pop, country, metal, blues, funk and punk blasted out from 9 bands from the CERN Musiclub and Jazz club, alternating on two stages in a non-stop show.  The night reached its hottest point when The Canettes Blues Band got everybody dancing to sixties R&B tunes (pictured). Meanwhile, the bars and food vans were working at full capacity, under the expert management of the CERN Softball club, who were at the same time running a Softball tournament in the adjacent "Higgs Field". The Hardronic Festival is the main yearly CERN music event, and it is organized with the support of the Staff Association and the CERN Administration.

  11. First salt making in Europe: an overview from Neolithic times

    Directory of Open Access Journals (Sweden)

    Olivier Weller

    2015-12-01

    Full Text Available This paper deals with the origin of salt production and discusses different approaches ranging from technology, ethnoarchaeology and paleoenvironmental studies to chemical analyses. Starting from the current research on the Neolithic exploitation of salt in Europe, we examine the types and nature of the salt resources (sea water, salt springs, soil or rock, the diversity of archaeological evidence of forms of salt working. We also scrutinize the types of production for these early forms of salt exploitation, with or without the use of crudely fired clay vessels (briquetage. Finally, we contextualise the socio-economic dimensions and highlight both the diversity of salt products and their characteristics, which go well beyond dietary roles.

  12. Study on Strength and Durability of Concrete by Partial Replacement of Fine Affregate Using Crushed Spent Fire Bricks

    Directory of Open Access Journals (Sweden)

    S. Keerthinarayana

    2010-01-01

    Full Text Available Concrete is the most undisputable and indispensable material being used in infrastructure development throughout the world. Umpteen varieties of concretes (FAC, HVFAC, FRC, HPC, HSC, and others were researched in several laboratories and brought to the field to suit the specific needs. Although natural fine aggregates (i.e., river sand are so far and/or will be superior to any other material in making concrete, their availability is continuously being depleted due to the intentional overexploitation through out the Globe. Hence, partial or full replacement of fine aggregates by the other compatible materials like sintered fly ash, crushed rock dust, quarry dust, glass powder, recycled concrete dust, and others are being researched from past two decades, in view of conserving the ecological balance. In this direction, an experimental investigation of strength and durability was undertaken to use “Spent Fire Bricks” (SFB (i.e. waste material from foundry bed and walls; and lining of chimney which is adopted in many industries for partial replacement of fine aggregate in concrete.

  13. Design of two crushing devices for release of the fluid inclusion volatiles

    Science.gov (United States)

    Dublyansky, Yuri

    2012-06-01

    Two crushing cells have been described for the release of volatiles from fluid inclusions in minerals in vacuum, static gas, and gas-flow applications. To minimize the adsorption of released volatiles on the freshly created mineral surfaces, both devices employed heated crushing. In the MTSN (Museo Tridentine di Scienze Naturali) crusher, samples were disintegrated by a piston driven by an induction coil. For efficient crushing, the electromagnet operated in dynamic impulse mode. In the LFU (Leopold-Franzens-Universität) crusher, the sample was disintegrated through the combined action of compression (manually operated hydraulic ram) and attrition. Crushers are able to be used in off-line and on-line modes, in gas chromatographic and mass spectrometric analyses.

  14. Simulation of Cobalt-Rich Crust's Crushing Process Based on ANSYS

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    It is a great concern in international oceanology to mine cobalt-rich crust. At present, spiral mining head is regarded as the best crushing scheme. Based on the dynamic model of spiral mining head, the of cobalt crust's crushing process was simulated with the ANSYS software. The material model of Johnson and Cook Plasticity, maximal principal stress failure criterion, and eroding contact arithmetic were selected. At the same time, the influence of cutting depth, feed speed, rotational speed of mining head on torque and force subjected by mining head was taken into account. At last a computer simulation model of crushing process of cobalt crust was established. By analyzing simulation results, the relationships among these controllable process parameters, torque and force can be obtained, which will provide a technical reference for practical mining system.

  15. Effect of hyperbaric oxygen on the regeneration of experimental crush injuries of nerves

    Directory of Open Access Journals (Sweden)

    Tuma Jr. Paulo

    1999-01-01

    Full Text Available Hyperbaric oxygen has been successfully used on treatment of acute ischemic injuries involving soft tissues and chronic injuries. In nerve crush injuries, the mechanisms involved are very similar to those found in ischemic injuries. Consequently, it is logical to hypothesize that hyperbaric oxygen should improve nerve repair, which is a critical step on functional recovery. In the present study, we created standard nerve crush injuries on sciatic nerves of rats, which underwent treatment with hyperbaric oxygen. Results were assessed by functional evaluation using walking-track analysis. The functional recovery indexes observed did not differ from control group. We concluded that hyperbaric oxygen therapy, in the schedule used, had no influence on functional recovery after nerve crush injuries.

  16. Greenhouse Gases and Energy Intensity of Granite Rock Mining Operations in Thailand: A Case of Industrial Rock-Construction

    Directory of Open Access Journals (Sweden)

    Kittipongvises Suthirat

    2016-12-01

    Full Text Available This paper is aimed to systematically assess greenhouse gases (GHGs and energy intensity of the granite rock mining operations in Thailand and also identify a range of feasible options to minimize their GHG emissions. Mining factories A, B and C, located in the Eastern region of Thailand, were selected as research case studies. The results indicated that the 3-year average of GHGs emissions from factories A to C was 3387 718 kgCO2e per year with approximately 2.92 kgCO2e per ton of granite rock produced over 2012 to 2014. Of this, the carbon intensity of grid-electricity consumption for the crushed rock production was 1.84 kgCO2/kWh. Diesel fuel combustion for transport activities in the mining factories was the greatest contributor to GHGs emissions (68 % compared to the purchased electricity and explosion process, with 31 % and 1 %, respectively. In-Pit Crushing and Conveying (IPCC installation, haul truck payload optimization and management, and reduction in tire rolling resistance have shown potential to reduce carbon emissions accounted for 20 % to 70 %.

  17. Greenhouse Gases and Energy Intensity of Granite Rock Mining Operations in Thailand: A Case of Industrial Rock-Construction

    Science.gov (United States)

    Kittipongvises, Suthirat; Chavalparit, Orathai; Sutthirat, Chakkaphan

    2016-12-01

    This paper is aimed to systematically assess greenhouse gases (GHGs) and energy intensity of the granite rock mining operations in Thailand and also identify a range of feasible options to minimize their GHG emissions. Mining factories A, B and C, located in the Eastern region of Thailand, were selected as research case studies. The results indicated that the 3-year average of GHGs emissions from factories A to C was 3387 718 kgCO2e per year with approximately 2.92 kgCO2e per ton of granite rock produced over 2012 to 2014. Of this, the carbon intensity of grid-electricity consumption for the crushed rock production was 1.84 kgCO2/kWh. Diesel fuel combustion for transport activities in the mining factories was the greatest contributor to GHGs emissions (68 %) compared to the purchased electricity and explosion process, with 31 % and 1 %, respectively. In-Pit Crushing and Conveying (IPCC) installation, haul truck payload optimization and management, and reduction in tire rolling resistance have shown potential to reduce carbon emissions accounted for 20 % to 70 %.

  18. Randomized Comparison of the Crush Versus the Culotte Stenting for Coronary Artery Bifurcation Lesions

    Institute of Scientific and Technical Information of China (English)

    Xu-Wei Zheng; Dong-Hui Zhao; Hong-Yu Peng; Qian Fan; Qin Ma; Zhen-Ye Xu; Chao Fan

    2016-01-01

    Background:The crush and the culotte stenting were both reported to be effective for complex bifurcation lesion treatment.However,their comparative performance remains elusive.Methods:A total of 300 patients with coronary bifurcation lesions were randomly assigned to crush (n =150) and culotte (n =150) treatment.The primary endpoint was the occurrence of major adverse cardiac events (MACEs) at 12 months including cardiac death,myocardial infarction,stent thrombosis,and target vessel revascularization.Index lesion restenosis at 12 months was a secondary endpoint.The surface integrals of time-averaged wall shear stress at bifurcation sites were also be quantified.Results:There were no significant differences in MACE rates between the two groups at 12-month follow-up:Crush 6.7%,culotte 5.3% (P =0.48).The rates of index lesion restenosis were 12.7% versus 6.0% (P =0.047) in the crush and the culotte groups,respectively.At 12-month follow-up,the surface integrals of time-averaged wall shear stress at bifurcation sites in the crush group were significantly lower than the culotte group ([5.01 ± 0.95] × 10-4 Newton and [6.08 ± 1.16] × 10 4 Newton,respectively;P =0.003).Conclusions:Both the crush and the culotte bifurcation stenting techniques showed satisfying clinical and angiographic results at 12-month follow-up.Bifurcation lesions treated with the culotte technique tended to have lower restenosis rates and more favorable flow patterns.

  19. VGLUT1 synapses and P-boutons on regenerating motoneurons after nerve crush.

    Science.gov (United States)

    Schultz, Adam J; Rotterman, Travis M; Dwarakanath, Anirudh; Alvarez, Francisco J

    2017-09-01

    Stretch-sensitive Ia afferent monosynaptic connections with motoneurons form the stretch reflex circuit. After nerve transection, Ia afferent synapses and stretch reflexes are permanently lost, even after regeneration and reinnervation of muscle by motor and sensory afferents is completed in the periphery. This loss greatly affects full recovery of motor function. However, after nerve crush, reflex muscle forces during stretch do recover after muscle reinnervation and reportedly exceed 140% baseline values. This difference might be explained by structural preservation after crush of Ia afferent synapses on regenerating motoneurons and decreased presynaptic inhibitory control. We tested these possibilities in rats after crushing the tibial nerve (TN), and using Vesicular GLUtamate Transporter 1 (VGLUT1) and the 65 kDa isoform of glutamic acid-decarboxylase (GAD65) as markers of, respectively, Ia afferent synapses and presynaptic inhibition (P-boutons) on retrogradely labeled motoneurons. We analyzed motoneurons during regeneration (21 days post crush) and after they reinnervate muscle (3 months). The results demonstrate a significant loss of VGLUT1 terminals on dendrites and cell bodies at both 21 days and 3 months post-crush. However, in both cellular compartments, the reductions were small compared to those observed after TN full transection. In addition, we found a significant decrease in the number of GAD65 P-boutons per VGLUT1 terminal and their coverage of VGLUT1 boutons. The results support the hypothesis that better preservation of Ia afferent synapses and a change in presynaptic inhibition could contribute to maintain or even increase the stretch reflex after nerve crush and by difference to nerve transection. © 2017 Wiley Periodicals, Inc.

  20. Compact, Non-Pneumatic Rock-Powder Samplers

    Science.gov (United States)

    Sherrit, Stewart; Bar-Cohen, Yoseph; Badescu, Mircea; Bao, Xiaoqi; Chang, Zensheu; Jones, Christopher; Aldrich, Jack

    2008-01-01

    Tool bits that automatically collect powdered rock, permafrost, or other hard material generated in repeated hammering action have been invented. The present invention pertains to the special case in which it is desired to collect samples in powder form for analysis by x-ray diffraction and possibly other techniques. The present invention eliminates the need for both the mechanical collection equipment and the crushing chamber and the pneumatic collection equipment of prior approaches, so that it becomes possible to make the overall sample-acquisition apparatus more compact.

  1. Characteristics of the development of pore stucture during carbonization of crushed and gradulated lean coal

    Energy Technology Data Exchange (ETDEWEB)

    Romanov, Yu.A.; Limonov, N.V.; Ivakhnyuk, G.K.

    1992-06-20

    The development of the pore structure of crushed and granulated lean coal during carbonization was investigated from the results of a study of the change of weight and volume of the coal pieces. It was shown that the macropore structure of the coal is formed in the low-temperature stage of carbonization and is due to the process of the removal of binder from the granules (620 K) and to destruction and elimination of volatile products from the crushed material (770 K). 9 refs., 2 figs., 3 tabs.

  2. Microstructure and Properties of Silty Siliceous Crushed Stone-lime Aerated Concrete

    Institute of Scientific and Technical Information of China (English)

    WANG Qiankun; CHEN Youzhi; LI Fangxian; SUN Tao; XU Bingbo

    2006-01-01

    The clayish crushed stone was used for making aerated concrete. Through studying hydro-thermal synthesis reaction, mix ratio, gas-forming and performance analysis, Grade-B05 and Grade-B06 aerated concrete were prepared successfully. The proper mix ratio and key processing parameters were achieved. The microstructure of aerated concrete with crush stone was analyzed by means of XRD and SEM. The experimental results indicate that the hydration products are poorly crystalline C-S-H (B), tobermorite and hydrogarnet. No component of clay was found. Unreacted SiO2 can be in existence, and the structure system of aerated concrete is homogeneous and dense.

  3. Efficacy of crushed lanthanum carbonate for hyperphosphatemia in hemodialysis patients undergoing tube feeding.

    Science.gov (United States)

    Kitajima, Yukie; Takahashi, Taeko; Sato, Yuzuru; Nakaya, Yutaka

    2011-08-01

    Lanthanum carbonate (LaC) is a non-calcium-based phosphate binder used to treat hyperphosphatemia in patients with chronic kidney disease. Oral administration of LaC is difficult in patients undergoing tube feeding or those who are of advanced age because it is essential to chew the LaC tablet sufficiently before swallowing it. We report two cases in whom crushed LaC was used in hemodialysis patients undergoing tube feeding. In both cases, previously crushed LaC was mixed into enteral nutrients. We found that LaC administered this way was effective for decreasing serum phosphorus levels.

  4. 3D Design and Analysis of Crushing Roller of High-pressure Grinding Roller

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Crushing roller is one of the main parts of High-p re ssure Grinding Roller, which is a kind of high efficient ore crushing equipment. A kind of assembled roller, which is more convenient to renovate worn surface b y simply replacing segmented surface of the roller, was developed. The structura l models of assembled roller's components were designed with SolidWorks softwar e based on feature modeling, these solid models of the roller were virtually ass embled. Through this work, not only was the assemble i...

  5. Fractal Characteristic of Rock Cutting Load Time Series

    Directory of Open Access Journals (Sweden)

    Hongxiang Jiang

    2014-01-01

    Full Text Available A test-bed was developed to perform the rock cutting experiments under different cutting conditions. The fractal theory was adopted to investigate the fractal characteristic of cutting load time series and fragment size distribution in rock cutting. The box-counting dimension for the cutting load time series was consistent with the fractal dimension of the corresponding fragment size distribution, which indicated that there were inherent relations between the rock fragmentation and the cutting load. Furthermore, the box-counting dimension was used to describe the fractal characteristic of cutting load time series under different conditions. The results show that the rock compressive strength, cutting depth, cutting angle, and assisted water-jet types all have no significant effect on the fractal characteristic of cutting load. The box-counting dimension can be an evaluation index to assess the extent of rock crushing or cutting. Rock fracture mechanism would not be changed due to water-jet in front of or behind the cutter, but it would be changed when the water-jet was in cutter.

  6. Energy analysis for damage and catastrophic failure of rocks

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The development history and current state of studies on the characteristics and mechanisms of deformation and failure of rock materials were briefly reviewed from the viewpoint of energy.The main scope and the achievable objectives of the energy-based research system were expatiated.It was validated by experiments that the damage process of rocks can be well described by the rock damage evolution equation established based on energy dissipation.It was found from the uniaxial compression and biaxial compression tests that only a small proportion of the total input energy in hard rocks is dissipated before peak load and a large proportion in soft rocks is dissipated before peak load.For both hard and soft rocks,the energy dissipated after peak load accounts for a greater proportion.More energy would be required for rock failure under equal biaxial compression than under unequal biaxial compression.The total absorbed energy is different for rock failure under high-rate loading and low-rate loading.More fragmented failure pattern usually corresponds to higher energy absorption.The mesoscopic analysis on the damage and failure of bedded salt rocks showed that the energy dissipation is prominent and the total absorbed energy for rock failure is low when cracks propagate in the weak mud interlayer while it is contrary when cracks propagate in the salt rock.The energy accumulation,transfer,dissipation and release during the failure process of tunnel with impending failure under disturbance were analyzed theoretically based on the elastoplastic mechanics theory.Furthermore,the spatial distribution of energy dissipation and energy release of fractured rocks under unloading was simulated numerically.It was demonstrated that energy is likely to be released from the weakest surface under compression,which triggers the global failure of rocks.

  7. Recovery of Salmonella serovar Enteritidis from inoculated broiler hatching eggs using shell rinse and shell crush sampling methods

    Science.gov (United States)

    This study compared the recovery of Salmonella from hatching eggs using three sampling methods (eggshell rinsing, eggshell crush following a previous rinse, and eggshell crush without previous rinse). Eggshells were drop-inoculated with approximately 10, 100, or 1,000 cfu/eggshell of S. Enteritidis...

  8. Sulphate rocks as an arena for karst development

    Directory of Open Access Journals (Sweden)

    Andrejchuk V.

    1996-01-01

    Full Text Available The rocks in which karst systems develop are most commonly composed of carbonate sulphate and chloride minerals. The sulphate minerals are quite numerous, but only gypsum and anhydrite form extensive masses in sedimentary sequences. Other minerals, which represent sulphates of K, Mg and Na, normally occur as minor beds (0.1-5.0 m, or as inclusions associated with chloride rocks. However some minerals precipitated in salt-generating basins, such as mirabilite and glauberite (typically formed in the Kara-Bogaz-Gol Gulf, salt lakes of Siberia and in China, form sequences up to 5-10 m thick where karst may develop. Due to the very high solubility of Na -sulphates, karst processes and features occurring in these rocks resemble salt karst. Thus, the term sulphate karst, although not strictly correct, is used mainly to indicate karst developed in gypsum and anhydrite.

  9. Effect of Hybridized Fiber Wrapped Around the Aluminum Tubes on the Crushing Performances

    Science.gov (United States)

    Ismail, A. E.; Noranai, Z.; Mohd Nor, N. H.; Mohd Tobi, A. L.; Ahmad, M. H.

    2016-11-01

    Nowadays, synthetic fibres for an example glass fibres is frequently used to wrap the metallic tubes in order to increase their load-bearing capacity. Due to environmental considerations and non-biodegradable behaviour, natural fibres or materials are increasingly used to replace synthetic fibres. The use of synthetic fibres can be minimized by combining them with natural fibres. Based on the literature survey, combining both fibres (synthetic and natural) for crushing applications are relatively new and therefore the main work of this paper is to present the crushing performances of hybridized fibres wrapped around the aluminium tubes when subjected to quasi-static crushing forces. Glass fibres are then combined with yarn kenaf fibres according to these volume fractions: 0, 25, 50, 75 and 100%. The hybridized fibres are wrapped around the tubes twice using different orientations [0o/0o], [15°/-15°], [30o/-30o] and [45o/-45o] included empty tubes before they are immersed into polyester resin bath. The composite tubes are then quasi-statically compressed using a constant cross-head displacement of 10mm/min. The force-displacement curves for each tube conditions are recorded automatically and analysed. The relation between hybridized fibbers and fibre orientations with crashworthiness parameters are investigated and discussed associating with their crushing mechanisms.

  10. Persistence of PAD and presynaptic inhibition of muscle spindle afferents after peripheral nerve crush.

    Science.gov (United States)

    Enríquez-Denton, M; Manjarrez, E; Rudomin, P

    2004-11-19

    Two to twelve weeks after crushing a muscle nerve, still before the damaged afferents reinnervate the muscle receptors, conditioning stimulation of group I fibers from flexor muscles depolarizes the damaged afferents [M. Enriquez, I. Jimenez, P. Rudomin, Changes in PAD patterns of group I muscle afferents after a peripheral nerve crush. Exp. Brain Res., 107 (1996), 405-420]. It is not known, however, if this primary afferent depolarization (PAD) is indeed related to presynaptic inhibition. We now show in the cat that 2-12 weeks after crushing the medial gastrocnemius nerve (MG), conditioning stimulation of group I fibers from flexors increases the excitability of the intraspinal terminals of both the intact lateral gastrocnemius plus soleus (LGS) and of the previously damaged MG fibers ending in the motor pool, because of PAD. The PAD is associated with the depression of the pre- and postsynaptic components of the extracellular field potentials (EFPs) evoked in the motor pool by stimulation of either the intact LGS or of the previously damaged MG nerves. These observations indicate, in contrast to what has been reported for crushed cutaneous afferents [K.W. Horch, J.W. Lisney, Changes in primary afferent depolarization of sensory neurones during peripheral nerve regeneration in the cat, J. Physiol., 313 (1981), 287-299], that shortly after damaging their peripheral axons, the synaptic efficacy of group I spindle afferents remains under central control. Presynaptic inhibitory mechanisms could be utilized to adjust the central actions of muscle afferents not fully recovered from peripheral lesions.

  11. Use of waste crushed glass for the production of hot-mix asphalt

    CSIR Research Space (South Africa)

    Anochie-Boateng, Joseph

    2016-08-01

    Full Text Available presents the development and evaluation of a new asphalt concrete mix that utilizes a sustainable crushed glass as a replacement material of a natural aggregate. The ultimate goal is to produce a cost-effective asphalt wearing course with comparative...

  12. Sea Dredged Gravel versus Crushed Granite as Coarse Aggregate for Self Compacting Concrete in Aggressive Environment

    DEFF Research Database (Denmark)

    Sørensen, Eigil V.; Kristensen, Lasse Frølich

    2007-01-01

    modulus of elasticity. Tensile and compressive strength were found to depend both on aggregate type and on the properties of the interfacial zone close to the aggregate surface. Freeze-thaw scaling resistance was good with crushed granite, whereas sea gravel led to more severe scaling caused by porphyry...

  13. Energy absorption of andwiched honeycombs with facesheets under in-plane crushing

    NARCIS (Netherlands)

    Atli-Veltin, B.; Gandhi, F.

    2013-01-01

    The in-plane crushing and energy absorption of sandwiched honeycomb cores with facesheets are examined through finite element simulations. Assuming no debonding between the facesheet and honeycomb core (which would be the case if manufacturing techniques such as brazing are used to produce very stro

  14. Expression of nerve growth factor in spinal dorsal horn following crushed spinal cord injury

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    AIM: The aim of this study was to explore the expression of nerve growth factor(NGF) in spinal dorsal horn following crushed spinal cord injury. METHODS: The adult Srague-Dawley rat model of crushed spinal cord injury was established by the method in our laboratory, and intact spinal cord was used as control. The rats were sacrificed respectively after 24 hours, 7 days, and 21 days of operation, and the L3 spinal segments were removed out and fixed in 4% polyformaldehyde. The segments were sectioned into sections of 20 μm in thickness. The sections were stained with anti-NGF antibody by ABC method of immunohistochemistry technique. The immunoreactive intensity of NGF and the number of positive neurons as well as glial cells in dorsal horn were observed and counted under light microscope. RESULTS: The number of positive cells and immunoreactive intensity of NGF increased gradually in the dorsal horn at 24 hours, 7 days and 21 days following crushed spinal cord injury compared with control group (P<0.01). CONCLUSION: These results indicated that NGF plays an important role in the postoperative reaction during the early period of the crushed spinal cord injury.

  15. Key factors of eddy current separation for recovering aluminum from crushed e-waste.

    Science.gov (United States)

    Ruan, Jujun; Dong, Lipeng; Zheng, Jie; Zhang, Tao; Huang, Mingzhi; Xu, Zhenming

    2017-02-01

    Recovery of e-waste in China had caused serious pollutions. Eddy current separation is an environment-friendly technology of separating nonferrous metallic particles from crushed e-waste. However, due to complex particle characters, separation efficiency of traditional eddy current separator was low. In production, controllable operation factors of eddy current separation are feeding speed, (ωR-v), and Sp. There is little special information about influencing mechanism and critical parameters of these factors in eddy current separation. This paper provided the special information of these key factors in eddy current separation of recovering aluminum particles from crushed waste refrigerator cabinets. Detachment angles increased as the increase of (ωR-v). Separation efficiency increased with the growing of detachment angles. Aluminum particles were completely separated from plastic particles in critical parameters of feeding speed 0.5m/s and detachment angles greater than 6.61deg. Sp/Sm of aluminum particles in crushed waste refrigerators ranged from 0.08 to 0.51. Separation efficiency increased as the increase of Sp/Sm. This enlightened us to develop new separator to separate smaller nonferrous metallic particles in e-waste recovery. High feeding speed destroyed separation efficiency. However, greater Sp of aluminum particles brought positive impact on separation efficiency. Greater Sp could increase critical feeding speed to offer greater throughput of eddy current separation. This paper will guide eddy current separation in production of recovering nonferrous metals from crushed e-waste.

  16. Synthesis of a Crushed Fullerene C60H24 through Sixfold Palladium-Catalyzed Arylation.

    Science.gov (United States)

    Dorel, Ruth; de Mendoza, Paula; Calleja, Pilar; Pascual, Sergio; González-Cantalapiedra, Esther; Cabello, Noemí; Echavarren, Antonio M

    2016-07-01

    The synthesis of a new C3v -symmetric crushed fullerene C60H24 (5) has been accomplished in three steps from truxene through sixfold palladium-catalyzed intramolecular arylation of a syn-trialkylated truxene precursor. Laser irradiation of 5 induces cyclodehydrogenation processes that result in the formation of C60, as detected by LDI-MS.

  17. Synthesis of a Crushed Fullerene C60H24 through Sixfold Palladium‐Catalyzed Arylation

    Science.gov (United States)

    Dorel, Ruth; de Mendoza, Paula; Calleja, Pilar; Pascual, Sergio; González‐Cantalapiedra, Esther; Cabello, Noemí

    2016-01-01

    The synthesis of a new C 3v‐symmetric crushed fullerene C60H24 (5) has been accomplished in three steps from truxene through sixfold palladium‐catalyzed intramolecular arylation of a syn‐trialkylated truxene precursor. Laser irradiation of 5 induces cyclodehydrogenation processes that result in the formation of C60, as detected by LDI‐MS. PMID:27774038

  18. An experimental study on the recovery of the hardened cement from crushed end of life concrete

    NARCIS (Netherlands)

    Lotfi, S.; Rem, P.C.

    2015-01-01

    In the C2CA concrete recycling process, autogenous milling of the crushed End of Life (EOL) concrete is a mechanical method to remove cement paste from the surface of aggregates. During autogenous milling, the combination of shearing and compression forces, promotes selective attrition and delivers

  19. 40 CFR 436.20 - Applicability; description of the crushed stone subcategory.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Applicability; description of the crushed stone subcategory. 436.20 Section 436.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS MINERAL MINING AND PROCESSING POINT SOURCE CATEGORY...

  20. Roof pre-blasting to prevent support crushing and water inrush accidents

    Institute of Scientific and Technical Information of China (English)

    Wang Xiaozhen; Xu Jialin; Zhu Weibing; Li Yingchun

    2012-01-01

    Support crushing and water inrush when mining under an unconsolidated confined aquifer in the Qidong Coal Mine was prevented by roof pre-blasting.The mechanism and applicable conditions for this method have been studied.The results show that when an overburden structure that may cause support crushing and a water inrush accident exists the weakening of the primary key stratum,which thereby reduces its weighting step,roof pre-blasting is both feasible and effective.If the position of the primary key stratum can be moved upward to exceed 10 times the mining height the possibility of support crushing and water inrush disaster caused by key stratum compound breakage will be lowered.The overburden structure of the number 7121 working face was considered during the design of a technical proposal involving roof pre-blasting.After comprehensively analyzing the applicability of roof pre-blasting the resulting design prevented support crushing and water inrush disasters from happening at the number 7121 working face and laid a solid foundation for mining safely.

  1. The effects of non-uniform environmental conditions on piglet crushing and maternal behavior of sows

    Science.gov (United States)

    Crushing is one of the main causes of piglet death in swine farrowing systems. Studies have shown a wide variability of piglet mortality rate among distinct litters, which has been associated with maternal ability of sows. In an effort to understand factors that affect sow maternal ability, this stu...

  2. Celecoxib accelerates functional recovery after sciatic nerve crush in the rat

    Directory of Open Access Journals (Sweden)

    Fernández-Garza Nancy E

    2008-11-01

    Full Text Available Abstract The inflammatory response appears to be essential in the modulation of the degeneration and regeneration process after peripheral nerve injury. In injured nerves, cyclooxygenase-2 (COX-2 is strongly upregulated around the injury site, possibly playing a role in the regulation of the inflammatory response. In this study we investigated the effect of celecoxib, a COX-2 inhibitor, on functional recovery after sciatic nerve crush in rats. Unilateral sciatic nerve crush injury was performed on 10 male Wistar rats. Animals on the experimental group (n = 5 received celecoxib (10 mg/kg ip immediately before the crush injury and daily for 7 days after the injury. Control group (n = 5 received normal saline at equal regimen. A sham group (n = 5, where sciatic nerve was exposed but not crushed, was also evaluated. Functional recovery was then assessed by calculating the sciatic functional index (SFI on days 0,1,7,14 and 21 in all groups, and registering the day of motor and walking onset. In comparison with control group, celecoxib treatment (experimental group had significant beneficial effects on SFI, with a significantly better score on day 7. Anti-inflammatory drug celecoxib should be considered in the treatment of peripheral nerve injuries, but further studies are needed to explain the mechanism of its neuroprotective effects.

  3. Rock fill in a KBS-3 repository. Rock material for filling of shafts and ramps in a KBS-3V repository in the closure phase

    Energy Technology Data Exchange (ETDEWEB)

    Pusch, Roland (Geodevelopment International AB/SWECO AB, Lund (Sweden))

    2008-09-15

    The content of large blocks in blasted rock makes it impossible to fill and compact the material effectively unless those larger than about 500 mm are removed. Tunnel Boring Machine (TBM) muck gives flat chips, that are usually not longer than a couple of decimeters, and serves better as backfill. The granulometrical composition of both types can be more suitable for effective compaction by crushing, which is hence a preferable process. Use of unsorted, unprocessed blasted rock can only be accepted if the density and physical properties, like self-compaction, are not important. Crushing of blasted rock and TBM muck for backfilling can be made in one or two steps depending on the required gradation. Placement of rock fill is best made by use of tractors with blades that push the material forwards over already placed and compacted material. The dry density of well graded rock fill effectively compacted by very heavy vibratory rollers can be as high as 2,400 kg/m3. For road compaction by ordinary vibratory rollers common dry density values are in the interval 2,050 to 2,200 kg m3. Blasted rock dumped and moved on site by tractors can get an average dry density of 1,600-1,800 kg/m3 without compaction. Crushed, blasted rock and TBM muck placed by tractors in horizontal layers and compacted by 5-10 t vibrating rollers in the lower part of the rooms, and moved by tractors to form inclined layers compacted by vibrating plates in the upper part, would get a dry density of 1,900-2,000 kg/m3. Flushing water over the rock fill in conjunction with the compaction work gives more effective densification than dry compaction. Based on recorded settlement of Norwegian rock fill dams constructed with water flushing it is estimated that the self-compaction of a 5 m high backfill of crushed rock or TBM muck causes a settlement of the top of the backfill of about 8 mm while a 200 m high shaft fill would undergo compression by more than half a meter. Repeated, strong earthquakes may

  4. 基于变形加固理论的盐岩库群时空演化分析%SPATIAL-TEMPORAL EVOLUTION ANALYSIS OF CAVERN GROUP IN SALT ROCK BASED ON DEFORMATION REINFORCEMENT THEORY

    Institute of Scientific and Technical Information of China (English)

    邓检强; 杨强; 刘耀儒

    2015-01-01

    In order to evaluate the long-term stability of underground cavern group for energy reserves,the elasto-viscoelastic-viscoplastic-viscodamage model is introduced into deformation reinforcement theory(DRT). The time-dependent deformation and damage evolution are considered. DRT considering the spatial-temporal evolution is developed. The criterion of long-term stability evaluation and failure spatial-temporal evolution of cavern group is established based on theT-∆E relationship curve,whereT is time and∆E is plastic complementary energy. The plastic complementary energy is the norm of over force,whose magnitude indicates the total evolution trend of long-term stability of cavern group;the over force is the internal effective driving force of non-equilibrium spatial-temporal evolution,which clearly exhibits the position and pattern of the damage evolution and failure. The long-term stability and the spatial-temporal evolution law of failure of double-cavern and Jintan oil and gas storage cavern group in salt deposit are studied. The results indicate that DRT considering spatial-temporal evolution provides a set of practical and effective theory and method for the long-term stability evaluation and failure analysis of spatial-temporal evolution of cavern group.%针对能源储备盐岩库群长期稳定性评价,将弹–黏弹–黏塑性损伤模型引入到变形加固理论,考虑时效变形和损伤演化,发展考虑时空演化的变形加固理论,建立基于T-∆E关系曲线的库群长期稳定性评价和破坏时空演化的关键判据,其中,T为时间,∆E为塑性余能。塑性余能是超屈服力的标量范数,其大小表征库群长期稳定的总体演化趋势;超屈服力是非平衡时空演化的内在有效驱动力,明确展现库群时效变形,损伤演化及破坏的部位和模式。研究双储库以及金坛盐矿油气储库群的长期稳定性和破坏时空演化规律。研究表明,考虑时空

  5. The effect of aquatic plant abundance on shell crushing resistance in a freshwater snail.

    Directory of Open Access Journals (Sweden)

    Johel Chaves-Campos

    Full Text Available Most of the shell material in snails is composed of calcium carbonate but the organic shell matrix determines the properties of calcium carbonate crystals. It has been shown that the deposition of calcium carbonate is affected by the ingestion of organic compounds. We hypothesize that organic compounds not synthesized by the snails are important for shell strength and must be obtained from the diet. We tested this idea indirectly by evaluating whether the abundance of the organic matter that snails eat is related to the strength of their shells. We measured shell crushing resistance in the snail Mexipyrgus churinceanus and the abundance of the most common aquatic macrophyte, the water lily Nymphaea ampla, in ten bodies of water in the valley of Cuatro Ciénegas, Mexico. We used stable isotopes to test the assumption that these snails feed on water lily organic matter. We also measured other factors that can affect crushing resistance, such as the density of crushing predators, snail density, water pH, and the concentration of calcium and phosphorus in the water. The isotope analysis suggested that snails assimilate water lily organic matter that is metabolized by sediment bacteria. The variable that best explained the variation in crushing resistance found among sites was the local abundance of water lilies. We propose that the local amount of water lily organic matter provides organic compounds important in shell biomineralization, thus determining crushing resistance. Hence, we propose that a third trophic level could be important in the coevolution of snail defensive traits and predatory structures.

  6. Thermal Analysis of Disposal of High-Level Nuclear Waste in a Generic Bedded Salt repository using the Semi-Analytical Method.

    Energy Technology Data Exchange (ETDEWEB)

    Hadgu, Teklu [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Matteo, Edward N. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-05-01

    An example case is presented for testing analytical thermal models. The example case represents thermal analysis of a generic repository in bedded salt at 500 m depth. The analysis is part of the study reported in Matteo et al. (2016). Ambient average ground surface temperature of 15°C, and a natural geothermal gradient of 25°C/km, were assumed to calculate temperature at the near field. For generic salt repository concept crushed salt backfill is assumed. For the semi-analytical analysis crushed salt thermal conductivity of 0.57 W/m-K was used. With time the crushed salt is expected to consolidate into intact salt. In this study a backfill thermal conductivity of 3.2 W/m-K (same as intact) is used for sensitivity analysis. Decay heat data for SRS glass is given in Table 1. The rest of the parameter values are shown below. Results of peak temperatures at the waste package surface are given in Table 2.

  7. A process for reducing rocks and concentrating heavy minerals

    Science.gov (United States)

    Strong, Thomas R.; Driscoll, Rhonda L.

    2016-03-30

    To obtain minerals suitable for age-dating and other analyses, it is necessary to first reduce the mineral-bearing rock to a fine, sand-like consistency. Reducing whole rock requires crushing, grinding, and sieving. Ideally, the reduced material should range in size from 80- to 270-mesh (an opening between wires in a sieve). The openings in an 80-mesh sieve are equal to 0.007 inches, 0.177 millimeters, or 177 micrometers. This size range ensures that compound grains are mostly disaggregated and that grains, in general, are dimensionally similar. This range also improves the segregation rate of conspicuous to extremely small individual heavy mineral grains.

  8. Modelling of excavation depth and fractures in rock caused by tool indentation

    Energy Technology Data Exchange (ETDEWEB)

    Kou Shaoquan; Tan Xiangchun; Lindqvist, P.A. [Luleaa Univ. of Technology (Sweden)

    1997-10-01

    The hydraulic regime after excavation in the near-field rock around deposition holes and deposition tunnels in a spent nuclear fuel repository is of concern for prediction of the saturation process of bentonite buffer and tunnel backfill. The hydraulic condition of main interest in this context is a result of the fracture network that is caused by the excavation. Modelling of the excavation disturbed zone in hard rocks caused by mechanical excavation has been carried out in the Division of Mining Engineering since 1993. This report contains an overview of the work conducted. The mechanical excavation is reasonably simplified as an indentation process of the interaction between rigid indenters and rocks. A large number of experiments have been carried out in the laboratory, and the results used for identifying crushed zones and fracture systems in rock under indentation are presented based on these experiments. The indentation causes crushing and damage of the rock and results in a crushed zone and a cracked zone. The indenter penetrates the rock with a certain depth when the force is over a threshold value relevant to the rock and tool. Outside the cracked zone there are basically three systems of cracks: median cracks, radial cracks, and side cracks. Fully developed radial cracks on each side of the indented area can connect with each other and join with median crack. This forms the so-called radial/median crack system. The influence of the mechanical properties of the rock is discussed based on our conceptual model, and the main factors governing the indentation event are summarised. The cracked zone is dealt with by an analytical fracture model. The side crack is simulated by applying the boundary element method coupled with fracture mechanics. Functional relationships are established relating either the indentation depth or the length of radial/median cracks to the various quantities characterising the physical event, namely the shape and the size of the

  9. Geotechnical Descriptions of Rock and Rock Masses.

    Science.gov (United States)

    1985-04-01

    weathering is presented by Dornbusch (1982). 39. Mechanical, or physical, weathering of rock occurs primarily by (a) freeze expansion (or frost wedging...34Engineering Classifica- tion of In-Situ Rock," Technical Report No. AFWL-TR-67-144, Air Force Weapons Laboratory, Kirtland Air Force Base, N. Mex. Dornbusch , W

  10. Consumption and diffusion of dissolved oxygen in sedimentary rocks.

    Science.gov (United States)

    Manaka, M; Takeda, M

    2016-10-01

    Fe(II)-bearing minerals (e.g., biotite, chlorite, and pyrite) are a promising reducing agent for the consumption of atmospheric oxygen in repositories for the geological disposal of high-level radioactive waste. To estimate effective diffusion coefficients (De, in m(2)s(-1)) for dissolved oxygen (DO) and the reaction rates for the oxidation of Fe(II)-bearing minerals in a repository environment, we conducted diffusion-chemical reaction experiments using intact rock samples of Mizunami sedimentary rock. In addition, we conducted batch experiments on the oxidation of crushed sedimentary rock by DO in a closed system. From the results of the diffusion-chemical reaction experiments, we estimated the values of De for DO to lie within the range 2.69×10(-11)concentration of reactive sites was about 10(-4)molm(-2) from batch experiments. In contrast, the value of reactive sites estimated from the physical surface area was about 10(-8)molm(-2), indicating that the reaction within intact rock is limited to the sites that originally existed with accessible porosity for O2(aq). This difference arises because the batch experiments used powdered samples, meaning that new sites which formed during milling were added to the original reaction sites. On the basis of these observations and interpretations, diffusion-chemical reaction experiments make it possible to determine the values of the kinetic parameter and diffusivity for an intact rock sample simultaneously. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Rock fragmentation control in opencast blasting

    Directory of Open Access Journals (Sweden)

    P.K. Singh

    2016-04-01

    Full Text Available The blasting operation plays a pivotal role in the overall economics of opencast mines. The blasting sub-system affects all the other associated sub-systems, i.e. loading, transport, crushing and milling operations. Fragmentation control through effective blast design and its effect on productivity are the challenging tasks for practicing blasting engineer due to inadequate knowledge of actual explosive energy released in the borehole, varying initiation practice in blast design and its effect on explosive energy release characteristic. This paper describes the result of a systematic study on the impact of blast design parameters on rock fragmentation at three mines in India. The mines use draglines and shovel–dumper combination for removal of overburden. Despite its pivotal role in controlling the overall economics of a mining operation, the expected blasting performance is often judged almost exclusively on the basis of poorly defined parameters such as powder factor and is often qualitative which results in very subjective assessment of blasting performance. Such an approach is very poor substitutes for accurate assessment of explosive and blasting performance. Ninety one blasts were conducted with varying blast designs and charging patterns, and their impacts on the rock fragmentation were documented. A high-speed camera was deployed to record the detonation sequences of the blasts. The efficiency of the loading machines was also correlated with the mean fragment size obtained from the fragmentation analyses.

  12. Can Low Water/Rock Hydrothermal Alteration of Impact Materials Explain the Rock Component of the Martian Soil?

    Science.gov (United States)

    Nelson, M. J.; Newsom, H. E.

    2003-01-01

    The martian regolith is a globally homogenized product of chemical and aeolian weathering processes. The soil is thought to consist of a rock component, with lesser amounts of mobile elements (Ca, Na, and K) than a presumed protolith, and a salt or mobile element component enriched in sulfur and chlorine. In this study we consider the contributions of hydrothermal processes to the origin of the rock component of the martian soil.

  13. The Rock Cycle

    Science.gov (United States)

    Singh, Raman J.; Bushee, Jonathan

    1977-01-01

    Presents a rock cycle diagram suitable for use at the secondary or introductory college levels which separates rocks formed on and below the surface, includes organic materials, and separates products from processes. (SL)

  14. Molten salt extraction of transuranic and reactive fission products from used uranium oxide fuel

    Science.gov (United States)

    Herrmann, Steven Douglas

    2014-05-27

    Used uranium oxide fuel is detoxified by extracting transuranic and reactive fission products into molten salt. By contacting declad and crushed used uranium oxide fuel with a molten halide salt containing a minor fraction of the respective uranium trihalide, transuranic and reactive fission products partition from the fuel to the molten salt phase, while uranium oxide and non-reactive, or noble metal, fission products remain in an insoluble solid phase. The salt is then separated from the fuel via draining and distillation. By this method, the bulk of the decay heat, fission poisoning capacity, and radiotoxicity are removed from the used fuel. The remaining radioactivity from the noble metal fission products in the detoxified fuel is primarily limited to soft beta emitters. The extracted transuranic and reactive fission products are amenable to existing technologies for group uranium/transuranic product recovery and fission product immobilization in engineered waste forms.

  15. Photo-Disintegration of the Iron Nucleus in Fractured Magnetite Rocks with Magnetostriction

    CERN Document Server

    Widom, A; Srivastava, Y N

    2013-01-01

    There has been considerable interest in recent experiments on iron nuclear disintegrations observed when rocks containing such nuclei are crushed and fractured. The resulting nuclear transmutations are particularly strong for the case of magnetite rocks, i.e. loadstones. We argue that the fission of the iron nucleus is a consequence of photo-disintegration. The electro-strong coupling between electromagnetic fields and nuclear giant dipole resonances are central for producing observed nuclear reactions. The large electron energies produced during the fracture of piezomagnetic rocks are closely analogous to the previously discussed case of the fracture of piezoelectric rocks. In both cases electro-weak interactions can produce neutrons and neutrinos from energetic protons and electrons thus inducing nuclear transmutations. The electro-strong condensed matter coupling discussed herein represents new many body collective nuclear photo-disintegration effects.

  16. The behaviour of salt and salt caverns

    NARCIS (Netherlands)

    Fokker, P.A.

    1995-01-01

    Salts are mined for both storage and extraction purposes, either via dry or solution mining techniques. For operational, environmental and geological purposes, it is important to understand and predict the in situ behaviour of salt, in particular the creep and strength characteristics. A micro-mecha

  17. My Pet Rock

    Science.gov (United States)

    Lark, Adam; Kramp, Robyne; Nurnberger-Haag, Julie

    2008-01-01

    Many teachers and students have experienced the classic pet rock experiment in conjunction with a geology unit. A teacher has students bring in a "pet" rock found outside of school, and the students run geologic tests on the rock. The tests include determining relative hardness using Mohs scale, checking for magnetization, and assessing luster.…

  18. My Pet Rock

    Science.gov (United States)

    Lark, Adam; Kramp, Robyne; Nurnberger-Haag, Julie

    2008-01-01

    Many teachers and students have experienced the classic pet rock experiment in conjunction with a geology unit. A teacher has students bring in a "pet" rock found outside of school, and the students run geologic tests on the rock. The tests include determining relative hardness using Mohs scale, checking for magnetization, and assessing luster.…

  19. Adaptation of oral medication in people institutionalized in nursing homes for whom medication is crushed: The ADECUA Study

    Directory of Open Access Journals (Sweden)

    Francisco Apolo Carvajal

    2016-12-01

    Full Text Available Purpose: To evaluate the effect of pharmacist interventions in the adaptation of pharmaceutical forms in elders institutionalized in nursing homes whose medicines are crushed, which may have a clinical relevance. Methods: Quasi-experimental, multicenter, transversal and prospective study carried out in 10 nursing homes. Subjects for whom drugs were being crushed were identified. Their treatments were reviewed in order to identify drugs that should not be crushed. In these cases, we proposed an alternative to the physician and we evaluated the degree of acceptance, its association to other variables and the pre-post adaptation index (tablets that can be crushed and capsules that can be opened/ total number of tablets and capsules before and after the intervention. Moreover, health professionals received a training course. Results: Medication was being crushed for 33% (618/1875 of residents (mean: 5 drugs susceptible of crushing. 220 pharmaceutical interventions were performed, mostly in extended release or gastro-resistant drugs (48% were accepted. Switch was the type of intervention more frequent (79%, mainly to Purpose: To evaluate the effect of pharmacist interventions in the adaptation of pharmaceutical forms in elders institutionalized in nursing homes whose medicines are crushed, which may have a clinical relevance. Methods: Quasi-experimental, multicenter, transversal and prospective study carried out in 10 nursing homes. Subjects for whom drugs were being crushed were identified. Their treatments were reviewed in order to identify drugs that should not be crushed. In these cases, we proposed an alternative to the physician and we evaluated the degree of acceptance, its association to other variables and the pre-post adaptation index (tablets that can be crushed and capsules that can be opened/ total number of tablets and capsules before and after the intervention. Moreover, health professionals received a training course. Results

  20. Salinization of the Upper Colorado River - Fingerprinting Geologic Salt Sources

    Science.gov (United States)

    Tuttle, Michele L.W.; Grauch, Richard I.

    2009-01-01

    Salt in the upper Colorado River is of concern for a number of political and socioeconomic reasons. Salinity limits in the 1974 U.S. agreement with Mexico require the United States to deliver Colorado River water of a particular quality to the border. Irrigation of crops, protection of wildlife habitat, and treatment for municipal water along the course of the river also place restrictions on the river's salt content. Most of the salt in the upper Colorado River at Cisco, Utah, comes from interactions of water with rock formations, their derived soil, and alluvium. Half of the salt comes from the Mancos Shale and the Eagle Valley Evaporite. Anthropogenic activities in the river basin (for example, mining, farming, petroleum exploration, and urban development) can greatly accelerate the release of constituents from these geologic materials, thus increasing the salt load of nearby streams and rivers. Evaporative concentration further concentrates these salts in several watersheds where agricultural land is extensively irrigated. Sulfur and oxygen isotopes of sulfate show the greatest promise for fingerprinting the geologic sources of salts to the upper Colorado River and its major tributaries and estimating the relative contribution from each geologic formation. Knowing the salt source, its contribution, and whether the salt is released during natural weathering or during anthropogenic activities, such as irrigation and urban development, will facilitate efforts to lower the salt content of the upper Colorado River.

  1. ROCKS & MINERALS DETERMINATION AND ANALYSIS

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    <正>20091570 Ge Yunjin(College of Geo-Resource and Information,China University of Petroleum,Dongying 257061,China);Chen Yong Advance in Low Temperature Phase Transition and Raman Spectrum Technique in Composition Determination of Fluid Inclusions(Rock and Mineral Analysis,ISSN0254-5357,CN11-2131/TD,27(3),2008,p.207-210,22 refs.)Key words:fluid inclusions,Raman spectraThe principle and development of low-temperature analytical techniques for fluid inclusions were expounded.The traditional low-temperature analytical technology mainly focused on the measurement of inorganic salt using congealed microthermometry,but now it is developed to semi-quantitative and quantitative analysis of fluid inclusions using in-situ cryogenic Raman spectrometry.

  2. Dilational and Compactional Shear Failure: Application to Siliciclastic Petroleum Reservoir rocks.

    Science.gov (United States)

    Casey, M.; Fisher, Q. J.; Knipe, R. J.

    2001-12-01

    Investigations related to the exploitation of oil reserves provide examples of brittle shear failure in rocks with well known burial, stress, temperature, compactional and diagenetic history. In addition, particular emphasis is placed on the dilational or compactional nature of the failure mode because of the influence this has on the permeability of the fault rocks. Microstructural investigations show that at shallow depths of less than 2.5 km failure during continued subsidence is by particulate flow and is usually compactional. At greater depths mechanical compaction may occur by particulate flow/ grain crushing or the rock may fail by dilational brittle failure. The main control on failure mode is the degree of cementation. At low cementation the rock fails by particulate flow (with or without fracture). Dilational shear failure occurs when the cementation has considerably reduced the porosity. We developed a model of cementation rate based on temperature controlled precipitation rate and used this to plot product of porosity and grain radius (a measure of susceptibility of the rock to crushing) against effective stress for some North Sea Reservoir rocks during their burial history. We found that the initially the low cementation rate held the crushing strength constant, causing the rocks to approach the empirical failure curve, but that at greater depths the increased cementation rate rapidly increased the strength, taking the rock mechanical state away from the failure line. Some deeply buried rocks were observed to have lower than expected amounts of cement and we ascribe this to the inhibition of precipitation by clay films. Deep, well cemented rocks, that failed by shear localised dilatant brittle shear were found to have higher permeabilities than expected on the basis of laboratory results. The natural specimens came from dilational jogs in a network of fault segments and we infer that the increased permeability is the result of deformation under

  3. Cooking without salt

    Science.gov (United States)

    DASH diet; High blood pressure - DASH; Hypertension - DASH; Low-salt diet - DASH ... Explore cooking with salt substitutes. Add a splash of lemon and other citrus fruits, or wine, to soups and other dishes. Or use them ...

  4. 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.

  5. Candy Crush : hábitos de consumo de una App de éxito

    OpenAIRE

    2014-01-01

    Amb l'aparició dels smartphones han nascut fenòmens com Candy Crush Saga, que en poc temps va aconseguir milions de descarregues i molts seguidors fidels. ¿Com pot ser que un joc gratuït hagi generat tants diners? ¿Per què un joc tan senzill, amb una mecànica tan explotada anteriorment ha enganxat, de cop a milions de persones d’arreu del mon? Amb una investigació dels hàbits de consum de Candy Crush s'han intentat resoldre qüestions com quan i on prefereixen jugar, quin es el seu vincle amb ...

  6. A study on the crushing behavior of basalt fiber reinforced composite structures

    Science.gov (United States)

    Pandian, A.; Veerasimman, A. P.; Vairavan, M.; Francisco, C.; Sultan, M. T. H.

    2016-10-01

    The crushing behavior and energy absorption capacity of basalt fiber reinforced hollow square structure composites are studied under axial compression. Using the hand layup technique, basalt fiber reinforced composites were fabricated using general purpose (GP) polyester resin with the help of wooden square shaped mould of varying height (100 mm, 150 mm and 200 mm). For comparison, similar specimens of glass fiber reinforced polymer composites were also fabricated and tested. Axial compression load is applied over the top end of the specimen with cross head speed as 2 mm/min using Universal Testing Machine (UTM). From the experimental results, the load-deformation characteristics of both glass fiber and basalt fiber composites were investigated. Crashworthiness and mode of collapse for the composites were determined from load-deformation curve, and they were then compared to each other in terms of their crushing behaviors.

  7. L-carnitine alleviates sciatic nerve crush injury in rats:functional and electron microscopy assessments

    Institute of Scientific and Technical Information of China (English)

    Ümmü Zeynep Avsar; Umit Avsar; Ali Aydin; Muhammed Yayla; Berna Ozturkkaragoz; Harun Un; Murat Saritemur; Tolga Mercantepe

    2014-01-01

    Several studies have demonstrated that L-carnitine exhibits neuroprotective effects on injured sciatic nerve of rats with diabetes mellitus. It is hypothesized that L-carnitine exhibits neuro-protective effects on injured sciatic nerve of rats. Rat sciatic nerve was crush injured by a forceps and exhibited degenerative changes. After intragastric administration of 50 and 100 mg/kg L-carnitine for 30 days, axon area, myelin sheath area, axon diameter, myelin sheath diameter, and numerical density of the myelinated axons of injured sciatic nerve were similar to normal, and the function of injured sciatic nerve also improved signiifcantly. These ifndings suggest that L-carnitine exhibits neuroprotective effects on sciatic nerve crush injury in rats.

  8. DEFORMATION CHARACTERISTICS OF CRUSHED-STONE LAYER UNDER CYCLIC IMPACT LOADING FROM MICRO-MECHANICAL VIEW

    Science.gov (United States)

    Kono, Akiko; Matsushima, Takashi

    'Hanging sleepers', which have gaps between sleepers and ballast layer are often found in the neighborhood of rail joints or rugged surface rails. This suggests that differential settlement of the ballast layer is due to impact loading generated by the contact between running wheel and rugged surface rail. Then cyclic loading tests were performed on crushed-stone layer with two loading patterns, the one is a cyclic impact loading and the other one is cyclic 'standard' loading controlled at 1/10 loading velocity of the impact loading. It was shown that the crashed-stone layer deforms with volumetric expansion during every off-loading processes under the cyclic impact loading. This phenomena prevents crushed stone layer from forming stable grain columns, then the residual settlement under the cyclic impact loading is larger than that under the cyclic 'standard' loading. A simple mass-spring model simulates that two masses move in the opposite direction with increased frequency of harmonic excitation.

  9. New regenerative treatment for tooth and periodontal bone defect associated with posttraumatic alveolar bone crush fracture.

    Science.gov (United States)

    Kiyokawa, Kensuke; Kiyokawa, Munekatsu; Takagi, Mikako; Rikimaru, Hideaki; Fukaya, Takuji

    2009-05-01

    We developed a new regenerative treatment of tooth and periodontal defect and tooth dislocation associated with posttraumatic alveolar bone crush fracture in the region of the maxillary anterior teeth. Using this method, dislocated teeth are first extracted and crushed alveolar bone is debrided. The dislocated teeth are then reimplanted, and cancellous iliac bone (bone marrow) is grafted to the area surrounding the teeth to regenerate periodontal bone. Tooth reimplantation was completely successful in 2 cases, and periodontal bone regenerated to a sufficient height with the iliac bone graft. Compared with the general method of treatment with a prosthesis (bridge), when using this method to treat cases such as these, there is no sacrifice of healthy teeth adjacent to the defect, and sufficient esthetic and functional recovery is possible. It is thought that this method could be applied as a new treatment of alveolar bone fracture in the future.

  10. Restorative effect and mechanism of mecobalamin on sciatic nerve crush injury in mice

    OpenAIRE

    Gan, Lin; Qian, Minquan; Shi, Keqin; Chen, Gang; GU, YANGLIN; Du, Wei; Zhu, Guoxing

    2014-01-01

    Mecobalamin, a form of vitamin B12 containing a central metal element (cobalt), is one of the most important mediators of nervous system function. In the clinic, it is often used to accelerate recovery of peripheral nerves, but its molecular mechanism remains unclear. In the present study, we performed sciatic nerve crush injury in mice, followed by daily intraperitoneal administration of mecobalamin (65 μg/kg or 130 μg/kg) or saline (negative control). Walking track analysis, histomorphologi...

  11. Protective effects of cerebrolysin in a rat model of optic nerve crush.

    Science.gov (United States)

    Huang, Tzu-Lun; Huang, Sun-Ping; Chang, Chung-Hsing; Lin, Kung-Hung; Sheu, Min-Muh; Tsai, Rong-Kung

    2014-07-01

    To investigate the effects of cerebrolysin (Cbl) on optic nerves (ON) and retinal ganglion cells (RGC) in a rat model of ON crush. Rats received intravitreal injection of Cbl (n = 20), intra-ON injection of Cbl (n = 20), intraperitoneal injection (IPI) of Cbl (n = 20), or phosphate buffered saline (PBS; n = 20) every day for 2 weeks after ON crush injury. At 3 weeks post-trauma, RGC density was counted by retrograde labeling with FluoroGold and visual function was assessed by flash visual-evoked potentials. Activities of microglia after insults were quantified by immunohistochemical analysis of the presence of ED1 in the optic nerve. At 3 weeks postcrush, the densities of RGCs in the Cbl-IVI group (1125 ± 166/mm(2)) and in the Cbl-IPI treatment group (1328 ± 119/mm(2)) were significantly higher than those in the PBS group (641 ± 214/mm(2)). The flash visual-evoked potential measurements showed that latency of the P1 wave was significantly shorter in the Cbl-IVI- and Cbl-IPI-treated groups (105 ± 4 ms and 118 ± 26 ms, respectively) than in the PBS-treated group (170 ± 20 ms). However, only Cbl IPI treatment resulted in a significant decrease in the number of ED1-positive cells at the lesion sites of the ON (5 ± 2 cells/vs. 30 ± 4 cells/high-power field in control eyes). Treatment with intra-ON injection of Cbl was harmful to the optic nerve in the crush model. Systemic administration of Cbl had neuroprotective effects on RGC survival and visual function in the optic nerve crush model.

  12. Study on Removal Distance of a Crushing Station in Buzhaoba Surface Mine

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A semi-continuous technology combines the merits of discontinuous and continuous technologies. Compared with the discontinuous technology, the semi-continuous technology can be used to decrease haulage costs in mines because of the use of a belt conveyor instead of trucks. The method may improve efficiency by using shovels instead of BWE. This paper discusses the removal distance of a crushing station based on the Buzhaoba surface mine.

  13. Entrapment of motor nerves in motor neuron disease: does double crush occur?

    OpenAIRE

    Chaudhry, V; Clawson, L L

    1997-01-01

    OBJECTIVE: To investigate whether "diseased nerves" are more prone to entrapment neuropathy than normal nerves. Nerve conduction studies of human neuropathies have shown that electrophysiological abnormalities are often most prominent at potential sites of nerve entrapment, and entrapments are more common in patients with radiculopathies--a concept designated as "double crush". As entrapment neuropathies commonly occur in otherwise healthy subjects, it is unclear whether this relation is coin...

  14. Neurturin enhances the recovery of erectile function following bilateral cavernous nerve crush injury in the rat

    Directory of Open Access Journals (Sweden)

    Klein Robert D

    2007-03-01

    Full Text Available Abstract Background The molecular mechanisms responsible for the survival and preservation of function for adult parasympathetic ganglion neurons following injury remain incompletely understood. However, advances in the neurobiology of growth factors, neural development, and prevention of cell death have led to a surge of clinical interest for protective and regenerative neuromodulatory strategies, as surgical therapies for prostate, bladder, and colorectal cancers often result in neuronal axotomy and debilitating loss of sexual function or continence. In vitro studies have identified neurturin, a glial cell line-derived neurotrophic factor, as a neuromodulator for pelvic cholinergic neurons. We present the first in vivo report of the effects of neurturin upon the recovery of erectile function following bilateral cavernous nerve crush injury in the rat. Methods In these experiments, groups (n = 8 each consisted of uninjured controls and animals treated with injection of albumin (blinded crush control group, extended release neurotrophin-4 or neurturin to the site of cavernous nerve crush injury (100 μg per animal. After 5 weeks, recovery of erectile function (treatment effect was assessed by cavernous nerve electrostimulation and peak aortic pressures were measured. Investigators were unblinded to specific treatments after statistical analyses were completed. Results Erectile dysfunction was not observed in the sham group (mean maximal intracavernous pressure [ICP] increase of 117.5 ± 7.3 cmH2O, whereas nerve injury and albumin treatment (control produced a significant reduction in ICP elevation of 40.0 ± 6.3 cmH2O. Neurturin facilitated the preservation of erectile function, with an ICP increase of 55% at 62.0 ± 9.2 cmH2O (p Conclusion Treatment with neurturin at the site of cavernous nerve crush injury facilitates recovery of erectile function. Results support further investigation of neurturin as a neuroprotective and/or neuroregenerative

  15. Malnutrition and inflammation in acute kidney injury due to earthquake-related crush syndrome

    OpenAIRE

    2010-01-01

    Abstract Background Malnutrition and inflammation are common and serious complications in patients with acute kidney injury (AKI). However, the profile of these complications in patients with AKI caused by crush syndrome (CS) remains unclear. This study describes the clinical characteristics of malnutrition and inflammation in patients with AKI and CS due to the Wenchuan earthquake. Methods One thousand and twelve victims and eighteen healthy adults were recruited to the study. They were divi...

  16. Neuropeptide expression and morphometric differences in crushed alveolar inferior nerve of rats: Effects of photobiomodulation.

    Science.gov (United States)

    Martins, Daniel Oliveira; Dos Santos, Fabio Martinez; Ciena, Adriano Polican; Watanabe, Ii-Sei; de Britto, Luiz Roberto G; Lemos, José Benedito Dias; Chacur, Marucia

    2017-05-01

    Inferior alveolar nerve (IAN) injuries may occur during various dental routine procedures, especially in the removal of impacted lower third molars, and nerve recovery in these cases is a great challenge in dentistry. Here, the IAN crush injury model was used to assess the efficacy of photobiomodulation (PBM) in the recovery of the IAN in rats following crushing injury (a partial lesion). Rats were divided into four experimental groups: without any procedure, IAN crush injury, and IAN crush injury with PBM and sham group with PBM. Treatment was started 2 days after surgery, above the site of injury, and was performed every other day, totaling 10 sessions. Rats were irradiated with GaAs Laser (Gallium Arsenide, Laserpulse, Ibramed Brazil) emitting a wavelength of 904 nm, an output power of 70 mWpk, beam spot size at target ∼0.1 cm(2), a frequency of 9500 Hz, a pulse time 60 ns, and an energy density of 6 J/cm(2). Nerve recovery was investigated by measuring the morphometric data of the IAN using TEM and by the expression of laminin, neurofilaments (NFs), and myelin protein zero (MPZ) using Western blot analysis. We found that IAN-injured rats which received PBM had a significant improvement of IAN morphometry when compared to IAN-injured rats without PBM. In parallel, all MPZ, laminin, and NFs exhibited a decrease after PBM. The results of this study indicate that the correlation between the peripheral nerve ultrastructure and the associated protein expression shows the beneficial effects of PBM.

  17. Bench-scale experimental determination of the thermal diffusivity of crushed tuff

    Energy Technology Data Exchange (ETDEWEB)

    Ryder, E.E.; Finley, R.E.; George, J.T.; Ho, C.K.; Longenbaugh, R.S. [Sandia National Labs., Albuquerque, NM (United States); Connolly, J.R. [New Mexico Univ., Albuquerque, NM (United States)

    1996-06-01

    A bench-scale experiment was designed and constructed to determine the effective thermal diffusivity of crushed tuff. Crushed tuff particles ranging from 12.5 mm to 37.5 mm (0.5 in. to 1.5 in.) were used to fill a cylindrical volume of 1.58 m{sup 3} at an effective porosity of 0.48. Two iterations of the experiment were completed; the first spanning approximately 502 hours and the second 237 hours. Temperatures near the axial heater reached 700 degrees C, with a significant volume of the test bed exceeding 100 degrees C. Three post-test analysis techniques were used to estimate the thermal diffusivity of the crushed tuff. The first approach used nonlinear parameter estimation linked to a one dimensional radial conduction model to estimate thermal diffusivity from the first 6 hours of test data. The second method used the multiphase TOUGH2 code in conjunction with the first 20 hours of test data not only to estimate the crushed tuffs thermal diffusivity, but also to explore convective behavior within the test bed. Finally, the nonlinear conduction code COYOTE-II was used to determine thermal properties based on 111 hours of cool-down data. The post-test thermal diffusivity estimates of 5.0 x 10-7 m{sup 2}/s to 6.6 x 10-7 m{sup 2}/s were converted to effective thermal conductivities and compared to estimates obtained from published porosity-based relationships. No obvious match between the experimental data and published relationships was found to exist; however, additional data for other particle sizes and porosities are needed.

  18. Protective effects of cerebrolysin in a rat model of optic nerve crush

    Directory of Open Access Journals (Sweden)

    Tzu-Lun Huang

    2014-07-01

    Full Text Available To investigate the effects of cerebrolysin (Cbl on optic nerves (ON and retinal ganglion cells (RGC in a rat model of ON crush. Rats received intravitreal injection of Cbl (n = 20, intra-ON injection of Cbl (n = 20, intraperitoneal injection (IPI of Cbl (n = 20, or phosphate buffered saline (PBS; n = 20 every day for 2 weeks after ON crush injury. At 3 weeks post-trauma, RGC density was counted by retrograde labeling with FluoroGold and visual function was assessed by flash visual-evoked potentials. Activities of microglia after insults were quantified by immunohistochemical analysis of the presence of ED1 in the optic nerve. At 3 weeks postcrush, the densities of RGCs in the Cbl-IVI group (1125 ± 166/mm2 and in the Cbl-IPI treatment group (1328 ± 119/mm2 were significantly higher than those in the PBS group (641 ± 214/mm2. The flash visual-evoked potential measurements showed that latency of the P1 wave was significantly shorter in the Cbl-IVI- and Cbl-IPI-treated groups (105 ± 4 ms and 118 ± 26 ms, respectively than in the PBS-treated group (170 ± 20 ms. However, only Cbl IPI treatment resulted in a significant decrease in the number of ED1-positive cells at the lesion sites of the ON (5 ± 2 cells/vs. 30 ± 4 cells/high-power field in control eyes. Treatment with intra-ON injection of Cbl was harmful to the optic nerve in the crush model. Systemic administration of Cbl had neuroprotective effects on RGC survival and visual function in the optic nerve crush model.

  19. Correlation of fat embolism severity and subcutaneous fatty tissue crushing and bone fractures.

    Science.gov (United States)

    Bolliger, Stephan Andreas; Muehlematter, Karin; Thali, Michael Josef; Ampanozi, Garyfalia

    2011-05-01

    Pulmonary fat embolism (PFE) is frequently encountered in blunt trauma. The clinical manifestation ranges from no impairment in light cases to death due to right-sided heart failure or hypoxaemia in severe cases. Occasionally, pulmonary fat embolism can give rise to a fat embolism syndrome (FES), which is marked by multiorgan failure, respiratory disorders, petechiae and often death. It is well known that fractures of long bones can lead to PFE. Several authors have argued that PFE can arise due to mere soft tissue injury in the absence of fractures, a claim other authors disagree upon. In this study, we retrospectively examined 50 victims of blunt trauma with regard to grade and extent of fractures and crushing of subcutaneous fatty tissue and presence and severity of PFE. Our results indicate that PFE can arise due to mere crushing of subcutaneous fat and that the fracture grade correlated well with PFE severity (p = 0.011). The correlation between PFE and the fracture severity (body regions affected by fractures and fracture grade) showed a lesser significant correlation (p = 0.170). The survival time (p = 0.567), the amount of body regions affected by fat crushing (p = 0.336) and the fat crush grade (p = 0.485) did not correlate with the PFE grade, nor did the amount of body regions affected by fractures. These results may have clinical implications for the assessment of a possible FES development, as, if the risk of a PFE is known, preventive steps can be taken.

  20. Regenerative Potential of D-δ-Tocotrienol Rich Fraction on Crushed Skeletal Muscle of Diabetic Rats

    Directory of Open Access Journals (Sweden)

    Bijo Elsy

    2017-06-01

    Full Text Available Background: Delayed muscle growth and regeneration of skeletal muscle in diabetics is believed to be due to diabetic myopathy because of alteration in the skeletal muscle homeostatis. Since vitamin E is a natural antioxidant and is also important for the integrity of sarcolemma, the present study was designed to explore the muscle regenerative potency of d-δ-tocotrienol-rich fraction (d-δ-TRF on crushed skeletal muscle in healthy and diabetic rats. Materials and Methods: Diabetes was induced through single subcutaneous injection of alloxan (100 mg/kg. Twenty-four albino rats were divided into four groups; healthy control, diabetic control, healthy treated, and diabetic treated. Treated groups received injections orally, daily (200 mg/kg for 3 weeks. A horizontal skin incision was made on the shaved right mid-thigh region, by splitting the fascia between gluteus maximus and tensor fascia lata, and gluteus maximus was crushed with Kocher’s forceps. Skin wound was closed with an absorbable suture. The crushed muscle changes were studied by assessing the histopathological features, histomorphological measurements, and biochemical analyses on 3rd week following induction of injury. One-way “ANOVA” followed by Tukey’s test and Student t-test were used for statistical analysis of data. Results: Results obtained through various methods indicate that the d-δ-TRF treated groups have controlled glycemic status, improved antioxidant capacity, faster revascularization, re-innervation, regeneration of myofibers, and connective tissue remodeling. Conclusion: It is, therefore, concluded that the d-δ-TRF is a beneficial nutritional adjuvant for skeletal muscles’ structural and functional recovery after crushed injury in both healthy and diabetics. [J Interdiscipl Histopathol 2017; 5(2.000: 36-42

  1. Rock History and Culture

    OpenAIRE

    Gonzalez, Éric

    2013-01-01

    Two ambitious works written by French-speaking scholars tackle rock music as a research object, from different but complementary perspectives. Both are a definite must-read for anyone interested in the contextualisation of rock music in western popular culture. In Une histoire musicale du rock (i.e. A Musical History of Rock), rock music is approached from the point of view of the people – musicians and industry – behind the music. Christophe Pirenne endeavours to examine that field from a m...

  2. Experimental and Modeling Studies of Crush, Puncture, and Perforation Scenarios in the Steven Impact Test

    Energy Technology Data Exchange (ETDEWEB)

    Vandersall, K S; Chidester, S K; Forbes, J W; Garcia, F; Greenwood, D W; Switzer, L L; Tarver, C M

    2002-06-28

    The Steven test and associated modeling has greatly increased the fundamental knowledge of practical predictions of impact safety hazards for confined and unconfined explosive charges. Building on a database of initial work, experimental and modeling studies of crush, puncture, and perforation scenarios were investigated using the Steven impact test. The descriptions of crush, puncture, and perforation arose from safety scenarios represented by projectile designs that ''crush'' the energetic material or either ''puncture'' with a pinpoint nose or ''perforate'' the front cover with a transportation hook. As desired, these scenarios offer different aspects of the known mechanisms that control ignition: friction, shear and strain. Studies of aged and previously damaged HMX-based high explosives included the use of embedded carbon foil and carbon resistor gauges, high-speed cameras, and blast wave gauges to determine the pressure histories, time required for an explosive reaction, and the relative violence of those reactions, respectively. Various ignition processes were modeled as the initial reaction rate expression in the Ignition and Growth reaction rate equations. Good agreement with measured threshold velocities, pressure histories, and times to reaction was calculated for LX-04 impacted by several projectile geometries using a compression dependent ignition term and an elastic-plastic model with a reasonable yield strength for impact strain rates.

  3. Effects of Palm Fiber on the Mechanical Properties of Lightweight Concrete Crushed Brick

    Directory of Open Access Journals (Sweden)

    Mahyuddin Ramli

    2010-01-01

    Full Text Available Problem statement: Researches has been conducted worldwide on a large number of natural or artificial lightweight aggregates. In spite of many of the researches of using natural fibers show considerable promise, the use of natural fibers to improve the properties of lightweight concrete still required to be a subject of further research and investigation. Approach: This experimental investigation was carried out to study the properties of lightweight crushed brick concrete containing palm fiber of different volume fractions. An experimental programme was planned in which the tests such as density, compressive strength and flexural strength were conducted to investigate the properties of lightweight crushed brick concrete reinforced by palm fiber. The specimen incorporated different volume fractions of palm fiber, i.e., 0, 0.2, 0.4, 0.6, 0.8 and 1.0%. Results: Tests results showed that the use of this fiber slightly increases the density of lightweight concrete. The use of 0.8% of palm fiber increases the compressive strength and flexural strength by about 13.4 and 16.1% respectively. Conclusion: The results indicated that the use of palm fiber with lightweight crushed brick concrete enhances the mechanical properties of the concrete and the optimization of the palm fiber fractions is required to get the best performance.

  4. Dynamic rupture and crushing of an extruded tube using artificial neural network (ANN) approximation method

    Institute of Scientific and Technical Information of China (English)

    Javad Marzbanrad; Behrooz Mashadi; Amir Afkar; Mostafa Pahlavani

    2016-01-01

    A numerical study of the crushing of thin-walled circular aluminum tubes has been carried out to investigate the crashworthiness behaviors under axial impact loading. These kinds of tubes are usually used in automobile and train structures to absorb the impact energy. Previous researches show that thin-walled circular tube has the highest energy absorption under axial impact amongst different structures. In this work, the crushing between two rigid flat plates and the tube rupture by 4 and 6 blades cutting tools is modeled with the help of ductile failure criterion using the numerical method. The tube material is aluminum EN AW-7108 T6 and its length and diameter are 300 mm and 50 mm, respectively. Using the artificial neural network (ANN), the most important surfaces of energy absorption parameters, including the maximum displacement of the striker, the maximum axial force, the specific energy absorption and the crushing force efficiency in terms of impact velocity and tube thickness are obtained and compared to each other. The analyses show that the tube rupture by the 6 blades cutting tool has more energy absorption in comparison with others. Furthermore, the results demonstrate that tube cutting with the help of multi-blades cutting tools is more stable, controllable and predictable than tube folding.

  5. Whole and crushed nutlets of chia (Salvia hispanica from Mexico as a source of functional gums

    Directory of Open Access Journals (Sweden)

    Maira Segura-Campos

    2014-12-01

    Full Text Available The objective of this study was to characterize the chemical and functional properties of Mexican chia (Salvia hispanica gums extracted from defatted whole and crushed nutlets using the Soxhlet and SFE-CO2 methods. Chia gums have interesting chemical and functional properties for the food industry. The oil and gum yields were in the range of 1.98-16.42% and 5.81-12.60%, respectively. The defatting procedure did not affect significantly the oil and gum extraction; the nutlet type (whole or crushed was the only parameter influencing the yield. The proximate composition and the protein and fiber contents of chia gum were evaluated. Low contents of protein and fiber and high NFE levels were found in whole nutlet gums. The functional properties of chia gum extracted from whole and crushed nutlets with the Soxhlet and SFE-COs methods showed the following ranges of water absorption capacity of 62.64 to 143.66 g/g, water adsorption capacity of 0.69 to 1.35 g/g, and water and oil holding capacity of 100 to 149.28 g/g and19.5 to 40.4 g/g, respectively. The rheological behavior exhibited by the gums was pseudoplastic or shear thinning. From a functional perspective, chia gum is an important food component due its emulsifier and stabilizer potentials.

  6. Early myelin breakdown following sural nerve crush: a freeze-fracture study

    Directory of Open Access Journals (Sweden)

    A.M.B. Martinez

    2000-12-01

    Full Text Available In this study we describe the early changes of the myelin sheath following surgical nerve crush. We used the freeze-fracture technique to better evaluate myelin alterations during an early stage of Wallerian degeneration. Rat sural nerves were experimentally crushed and animals were sacrificed by transcardiac perfusion 30 h after surgery. Segments of the nerves were processed for routine transmission electron microscopy and freeze-fracture techniques. Our results show that 30 h after the lesion there was asynchrony in the pattern of Wallerian degeneration, with different nerve fibers exhibiting variable degrees of axon disruption. This was observed by both techniques. Careful examination of several replicas revealed early changes in myelin membranes represented by vacuolization and splitting of consecutive lamellae, rearrangement of intramembranous particles and disappearance of paranodal transverse bands associated or not with retraction of paranodal myelin terminal loops from the axolemma. These alterations are compatible with a direct injury to the myelin sheath following nerve crush. The results are discussed in terms of a similar mechanism underlying both axon and myelin breakdown.

  7. Early myelin breakdown following sural nerve crush: a freeze-fracture study.

    Science.gov (United States)

    Martinez, A M; Canavarro, S

    2000-12-01

    In this study we describe the early changes of the myelin sheath following surgical nerve crush. We used the freeze-fracture technique to better evaluate myelin alterations during an early stage of Wallerian degeneration. Rat sural nerves were experimentally crushed and animals were sacrificed by transcardiac perfusion 30 h after surgery. Segments of the nerves were processed for routine transmission electron microscopy and freeze-fracture techniques. Our results show that 30 h after the lesion there was asynchrony in the pattern of Wallerian degeneration, with different nerve fibers exhibiting variable degrees of axon disruption. This was observed by both techniques. Careful examination of several replicas revealed early changes in myelin membranes represented by vacuolization and splitting of consecutive lamellae, rearrangement of intramembranous particles and disappearance of paranodal transverse bands associated or not with retraction of paranodal myelin terminal loops from the axolemma. These alterations are compatible with a direct injury to the myelin sheath following nerve crush. The results are discussed in terms of a similar mechanism underlying both axon and myelin breakdown.

  8. Crushing Candy: The Free-to-Play Game in Its Connective Commodity Form

    Directory of Open Access Journals (Sweden)

    David B. Nieborg

    2015-12-01

    Full Text Available The goal of this article is to add a complementary perspective to the study of social network sites by surveying how the political economy of social media platforms relates to the structure of free-to-play games in their commodity form. Drawing on the theory of multisided markets and critical political economy, this article surveys the political economy of game apps and investigates how it is symbiotically related to the technological and economic logic underlying connective platforms operated by Google, Apple, Facebook, and Amazon. These social media platforms operate app stores that sustain the transformation of games as fixed, physically distributed products that follow a transaction logic, into digitally distributed, freely accessible, or “free-to-play” apps. Through a case study of the popular casual game Candy Crush Saga it is contended that the connective properties of social media platforms affect the form and format of game apps as cultural commodities. Candy Crush Saga developer King Digital Entertainment has been able to attract hundreds of millions of players and build a business model that combines the commodification of virtual items, connectivity, user attention, user data, and play. It is argued that the free-to-play commodity form comprises three commodity types: the product commodity, the “prosumer commodity,” and the player commodity. Furthermore, Candy Crush Saga’s commodity form is structured by a platformed modality of cultural production and circulation and therefore embedded in the political economy of its host platform.

  9. Residual Mechanical Properties of Concrete Made with Crushed Clay Bricks and Roof Tiles Aggregate after Exposure to High Temperatures

    Directory of Open Access Journals (Sweden)

    Ivana Miličević

    2016-04-01

    Full Text Available This paper presents the residual mechanical properties of concrete made with crushed bricks and clay roof tile aggregates after exposure to high temperatures. One referent mixture and eight mixtures with different percentages of replacement of natural aggregate by crushed bricks and roof tiles are experimentally tested. The properties of the concrete were measured before and after exposure to 200, 400, 600 and 800 °C. In order to evaluate the basic residual mechanical properties of concrete with crushed bricks and roof tiles after exposure to high temperatures, ultrasonic pulse velocity is used as a non-destructive test method and the results are compared with those of a destructive method for validation. The mixture with the highest percentage of replacement of natural aggregate by crushed brick and roof tile aggregate has the best physical, mechanical, and thermal properties for application of such concrete in precast concrete elements exposed to high temperatures.

  10. The disturbed rock zone at the Waste Isolation Pilot Plant.

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Francis D.

    2003-12-01

    The Disturbed Rock Zone constitutes an important geomechanical element of the Waste Isolation Pilot Plant. The science and engineering underpinning the disturbed rock zone provide the basis for evaluating ongoing operational issues and their impact on performance assessment. Contemporary treatment of the disturbed rock zone applied to the evaluation of the panel closure system and to a new mining horizon improves the level of detail and quantitative elements associated with a damaged zone surrounding the repository openings. Technical advancement has been realized by virtue of ongoing experimental investigations and international collaboration. The initial portion of this document discusses the disturbed rock zone relative to operational issues pertaining to re-certification of the repository. The remaining sections summarize and document theoretical and experimental advances that quantify characteristics of the disturbed rock zone as applied to nuclear waste repositories in salt.

  11. The salts of Mars

    Science.gov (United States)

    Clark, B. C.; Van Hart, D. C.

    1981-01-01

    Salt compounds are apparently an important component of the fine-grained regolith on Mars. Salt enrichment may be explained either as a secondary concentration of chemical weathering products or as direct incorporation of planetary released volatiles. Geochemical measurements and chemical relationships constrain the salt species and resultant physicochemical consequences. A likely assemblage is dominated by (Mg,Na)SO4, NaCl, and (Mg,Ca)CO3. Formation of brine in equilibrium with such a salt mixture is unlikely under the temperature and water-vapor restrictions prevalent over most, if not all, of the Martian surface. Acidic conditions, accompanying salt formation, favor the preferential destruction of susceptible igneous minerals.

  12. DEVELOPMENT OF CONTROLLED IMPULSE TECHNIQUE FOR IN SITU TESTING OF ROCK

    Science.gov (United States)

    Transmission distances attained varied from 55 feet in strongly hydrothermally altered porphyry copper ore to 1,373 feet in sylvitehalite. Data...pulses through various types of rock in place. Rock masses tested were granitic gneiss schist, potash rich salt beds, and porphyry -copper ore. The

  13. A velocity-based approach to visco-elastic flow of rock

    NARCIS (Netherlands)

    Zijl, W.; Hendriks, M.; Hart, M. 't

    2005-01-01

    In structural geology, viscous creep is generally recognized as the major deformation mechanism in the folding of rock layers through geological time scales of hundreds of thousands of years. Moreover, since deformation of rock salt by creep takes already place on relatively small time scales - week

  14. A velocity-based approach to visco-elastic flow of rock

    NARCIS (Netherlands)

    Zijl, W.; Hendriks, M.; Hart, M. 't

    2005-01-01

    In structural geology, viscous creep is generally recognized as the major deformation mechanism in the folding of rock layers through geological time scales of hundreds of thousands of years. Moreover, since deformation of rock salt by creep takes already place on relatively small time scales -

  15. The Beneficial Effects of ETS-GS, a Novel Vitamin E Derivative, on a Rat Model of Crush Injury.

    Science.gov (United States)

    Nakagawa, Junichiro; Matsumoto, Naoya; Nakane, Yuko; Yamakawa, Kazuma; Yamada, Tomoki; Matsumoto, Hisatake; Shimazaki, Junya; Imamura, Yukio; Ogura, Hiroshi; Jin, Takashi; Shimazu, Takeshi

    2016-12-01

    Crush syndrome is a devastating condition leading to multiple organ failure. The mechanisms by which local traumatic injuries affect distant organs remain unknown. ETS-GS is a novel water-soluble, stable anti-oxidative agent composed of vitamin E derivative. Given that one of the main pathophysiological effects in crush syndrome is massive ischemia-reperfusion, reactive oxygen species (ROS) generated from the injured extremities would be systemically involved in distant organ damage. We investigated whether ETS-GS could suppress inflammatory response and improve mortality in a rat model of crush injury. Crush injury was induced by compression of bilateral hindlimbs for 6 h followed by release of compression. Seven-day survival was significantly improved by ETS-GS treatment. To estimate anti-oxidative and anti-inflammatory effects of ETS-GS, serum was collected 6 and 20 h after the injury. ETS-GS treatment significantly dampened the up-regulation of malondialdehyde and reduction of superoxide dismutase in the serum, which were induced by crush injury. Serum levels of interleukin 6 and high mobility group box 1 were significantly decreased in the ETS-GS group compared with those in the control group. Lung damage shown by hematoxylin-eosin staining at 20 h after the injury was ameliorated by the treatment. Ex vivo imaging confirmed that ETS-GS treatment reduced ROS generation in both the lung and the muscle following crush injury. The administration of ETS-GS could suppress ROS generation, systemic inflammation, and the subsequent organ damage, thus improving survival in a rat model of crush injury. These findings suggest that ETS-GS can become a novel therapeutic agent against crush injury.

  16. Compaction bands in porous rocks: localization analysis using breakage mechanics

    Science.gov (United States)

    Das, Arghya; Nguyen, Giang; Einav, Itai

    2010-05-01

    It has been observed in fields and laboratory studies that compaction bands are formed within porous rocks and crushable granular materials (Mollema and Antonellini, 1996; Wong et al., 2001). These localization zones are oriented at high angles to the compressive maximum principal stress direction. Grain crushing and pore collapse are the integral parts of the compaction band formation; the lower porosity and increased tortuosity within such bands tend to reduce their permeability compared to the outer rock mass. Compaction bands may thereafter act as flow barriers, which can hamper the extraction or injection of fluid into the rocks. The study of compaction bands is therefore not only interesting from a geological viewpoint but has great economic importance to the extraction of oil or natural gas in the industry. In this paper, we study the formation of pure compaction bands (i.e. purely perpendicular to the principal stress direction) or shear-enhanced compaction bands (i.e. with angles close to the perpendicular) in high-porosity rocks using both numerical and analytical methods. A model based on the breakage mechanics theory (Einav, 2007a, b) is employed for the present analysis. The main aspect of this theory is that it enables to take into account the effect that changes in grain size distribution has on the constitutive stress-strain behaviour of granular materials at the microscopic level due to grain crushing. This microscopic phenomenon of grain crushing is explicitly linked with a macroscopic internal variable, called Breakage, so that the evolving grain size distribution can be continuously monitored at macro scale during the process of deformation. Through the inclusion of an appropriate parameter the model is also able to capture the effects of pore collapse on the macroscopic response. Its possession of few physically identifiable parameters is another important feature which minimises the effort of their recalibration, since those become less

  17. Changes in PAD patterns of group I muscle afferents after a peripheral nerve crush.

    Science.gov (United States)

    Enríquez, M; Jiménez, I; Rudomin, P

    1996-01-01

    In the anesthetized cat we have analyzed the changes in primary afferent depolarization (PAD) evoked in single muscle spindle and tendon organ afferents at different times after their axons were crushed in the periphery and allowed to regenerate. Medial gastrocnemius (MG) afferents were depolarized by stimulation of group I fibers in the posterior biceps and semitendinosus nerve (PBSt), as soon as 2 weeks after crushing their axons in the periphery, in some cases before they could be activated by physiological stimulation of muscle receptors. Two to twelve weeks after crushing the MG nerve, stimulation of the PBSt produced PAD in all MG fibers reconnected with presumed muscle spindles and tendon organs. The mean amplitude of the PAD elicited in afferent fibers reconnected with muscle spindles was increased relative to values obtained from Ia fibers in intact (control) preparations, but remained essentially the same in fibers reconnected with tendon organs. Quite unexpectedly, we found that, between 2 and 12 weeks after crushing the MG nerve, stimulation of the bulbar reticular formation (RF) produced PAD in most afferent fibers reconnected with muscle spindle afferents. The mean amplitude of the PAD elicited in these fibers was significantly increased relative to the PAD elicited in muscle spindle afferents from intact preparations (from 0.08 +/- 0.4 to 0.47 +/- 0.34 mV). A substantial recovery was observed between 6 months and 2.5 years after the peripheral nerve injury. Stimulation of the sural (SU) nerve produced practically no PAD in muscle spindles from intact preparations, and this remained so in those afferents reconnected with muscle spindles impaled 2-12 weeks after the nerve crush. The mean amplitude of the PAD produced in afferent fibers reconnected with tendon organs by stimulation of the PBSt nerve and of the bulbar RF remained essentially the same as the PAD elicited in intact afferents. However, SU nerve stimulation produced a larger PAD in afferents

  18. Principles of rock mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Turchaninov, I.A.; Iofis, M.A.; Kasparyan, E.V.

    1979-01-01

    This book presents the principles of rock mechanics in a systematic way, reflecting both the historic development and the contemporary status of theoretical and experimental techniques used for the determination of the properties and stress state of rock masses, calculation of elements of systems for exploitation of useful mineral deposits and the design of mine openings. The subject of rock mechanics is discussed and methods and basic approaches are analyzed. The most widely used methods for determining the properties of rock in specimens and in situ are described. Problems of determining the stress strain state of the rock around mine openings by both experimental and analytic methods are discussed. The primary results of the study of the stress state of rock around main, development and production openings are presented. Problems of the movement of rock due to extraction of minerals are analyzed in detail, as are the conditions and causes of the development of rock bursts and sudden release of rock and gas in both surface and underground mines. Procedures for preventing or localizing rock bursts or sudden outbursts are described. (313 refs.)

  19. Compact rock material gas permeability properties

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Huanling, E-mail: whl_hm@163.com [Key Laboratory of Coastal Disaster and Defence, Ministry of Education, Hohai University, Nanjing 210098 (China); LML, University of Lille, Cite Scientifique, 59655 Villeneuve d’Ascq (France); Xu, Weiya; Zuo, Jing [Institutes of Geotechnical Engineering, Hohai University, Nanjing 210098 (China)

    2014-09-15

    Natural compact rocks, such as sandstone, granite, and rock salt, are the main materials and geological environment for storing underground oil, gas, CO{sub 2,} shale gas, and radioactive waste because they have extremely low permeabilities and high mechanical strengths. Using the inert gas argon as the fluid medium, the stress-dependent permeability and porosity of monzonitic granite and granite gneiss from an underground oil storage depot were measured using a permeability and porosity measurement system. Based on the test results, models for describing the relationships among the permeability, porosity, and confining pressure of rock specimens were analyzed and are discussed. A power law is suggested to describe the relationship between the stress-dependent porosity and permeability; for the monzonitic granite and granite gneiss (for monzonitic granite (A-2), the initial porosity is approximately 4.05%, and the permeability is approximately 10{sup −19} m{sup 2}; for the granite gneiss (B-2), the initial porosity is approximately 7.09%, the permeability is approximately 10{sup −17} m{sup 2}; and the porosity-sensitivity exponents that link porosity and permeability are 0.98 and 3.11, respectively). Compared with moderate-porosity and high-porosity rocks, for which φ > 15%, low-porosity rock permeability has a relatively lower sensitivity to stress, but the porosity is more sensitive to stress, and different types of rocks show similar trends. From the test results, it can be inferred that the test rock specimens’ permeability evolution is related to the relative particle movements and microcrack closure.

  20. Internally Pressurized Spherical and Cylindrical Cavities in Rock Salt

    DEFF Research Database (Denmark)

    Krenk, Steen

    1978-01-01

    The paper deals with the stress distribution around cavities under pressure in an infinite, non-linear elastic material. A homogeneous stress state is assumed at infinity. For spherical and cylindrical cavities simple formulae are derived for the stress concentration, the extent of the non-linear...

  1. Rock Breaking by Conical Pick Assisted with High Pressure Water Jet

    Directory of Open Access Journals (Sweden)

    Liu Songyong

    2014-03-01

    Full Text Available In the process of hard rock breaking, the conical pick bears great cutting force and wear, and the cutting efficiency is lower. Thus different combination ways of water jet and conical pick were proposed to solve this issue; for instance, water jet placed in the front of pick (JFP and water jet through the center of pick (JCP was researched by numerical simulation and experiments in this paper. First, the models of rock breaking were built based on SPH combined with finite element method. Then, the stress distribution of rock and the cut force of pick were analyzed when the rock broken by the conical pick assisted with the high pressure water jet. It indicates that the effect of the JCP on rock breaking is better than the JFP. At last, experiments about rock breaking with a conical pick and the JCP were conducted to verify the reliability of the simulation. It indicates that the rock breaking with the assistance of high pressure water jet cannot only reduce the pick force, but also increase the rock crushing volume.

  2. Results of hydraulic tests in wells DOE-1, 2, 3, Salt Valley, Grand County, Utah

    Science.gov (United States)

    Rush, F. Eugene; Hart, I.M.; Whitfield, M.S.; Giles, T.F.; D'Epagnier, T. E.

    1980-01-01

    Three exploratory wells were drilled for geological, geophysical, and hydrological purposes in Salt Valley, Grand County, Utah. Cap rock, salt, and interbeds of the Paradox Member of the Hermosa Formation of Middle Pennsylvanian age were penetrated. The observed depth below land surface of the cap rock-salt interface ranges from 163 meters (m) to 191 meters. Approximately the upper 100 meters of cap rock were unsaturated by ground water. Within the saturated part of the cap rock, hydraulic heads generally decrease with depth and southwestward. Ion concentrations generally increase with depth in the saturated cap rock.Hydraulic conductivity of cap rock, as determined from pumping tests, may be on the order of 5 x 10-3 meters per day; as a result, ground-water flow rates in the cap rock are probably very low. A carbon 14 specific activity for cap rock water yielded an uncorrected "age" of greater than 36,000 years. Salt and interbeds have hydraulic conductivities probably less than 1 x 10-4 meters per day.

  3. Aespoe Hard Rock Laboratory. Annual Report 2002

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-06-01

    origin and age of matrix fluids, i.e. accessible pore water, in fissures and small-scale fractures and their possible influence on fluid chemistry in the bedrock. When the EC-project EQUIP, which concentrated on the formulation of a methodology for how to conduct a palaeo hydrogeological study, ended in 2000 there was a need for continued fracture mineral investigations and model testing of the obtained results and a new EC-project was initiated in the beginning of 2002. This project is called PADAMOT (Palaeo hydrogeological Data Analysis and Model Testing) and includes further developments of analytical techniques and modelling tools to interpret data, but also further research to investigate specific processes that might link climate and groundwater properties in low permeability rocks. The project Demonstration of repository technology provides a full-scale demonstration of canister deposition under radiation-shielded conditions and works with testing of canister and bentonite handling in full size deposition holes. The Prototype Repository project focuses on testing and demonstrating repository system function in full scale and is co-funded by the EC. The experiment comprises six full size canisters with electrical heaters surrounded by bentonite. The Backfill and Plug Test is a test of the hydraulic and mechanical function of different backfill materials, emplacement methods, and a full-scale plug. The 28 m long test region is located in the ZEDEX drift. The inner part of the drift is backfilled with a mixture of bentonite and crushed rock and the outer part is filled with crushed rock. The wetting of the backfill started late 1999 and the final step of increasing the water pressure in the mats to 500 kPa was taken in January 2002. The Canister Retrieval Test, located in the main test area at the 420 m level, is aiming at demonstrating the readiness for recovering of emplaced canisters also after the time when the bentonite is fully saturated. The Long Term Test of

  4. Process for cleaning up hard coal mines containing salt water. Verfahren zur Entsorgung von salzwasserfuehrenden Steinkohlenzechen

    Energy Technology Data Exchange (ETDEWEB)

    Hoelter, H.; Igelbuescher, H.; Gresch, H.; Dewert, H.

    1987-03-12

    The process for cleaning up pits with a great deal of salt water in them and the associated high proportion of flotation material is characterized by the fact that the pre-treated salt water content forms a mass with the flotation coal/rock mass, which is burnt to a residue in fluidized-bed combustion, where the residue as a building material containing salt is particularly suitable for building roads and paths secure against frost and for similar building processes.

  5. Molecular and carbon isotopic compositions of gas inclusions of deep carbonate rocks in the Tarim Basin

    Institute of Scientific and Technical Information of China (English)

    ZHOU Shixin; WANG Xianbin; MENG Zifang; LI Yuan; Paul Farrimond; LI Liwu; DUAN Yi

    2004-01-01

    Gaseous components of gas inclusions in deep carbonate rocks (>5700 m) from the Tacan 1 well were analyzed by online mass spectrometry by means of either the stepwise heating technique or vacuum electromagnetism crushing. The carbon isotopic compositions of gases released by vacuum electromagnetism crushing were also measured. Although the molecular compositions of gas inclusions show differences between the two methods, the overall characteristics are that gas inclusions mainly contain CO2, whilst hydrocarbon gases, such as CH4, C2H6 and C3H8, are less abundant. The content of CO is higher in the stepwise heating experiment than that in the method of vacuum electromagnetism crushing, and there are only minor amounts of N2, H2 and O2 in gas inclusions. Methane δ13C values of gas inclusions in Lower Ordovician and Upper Cambrian rocks (from 5713.7 to 6422 m; -52‰-63‰) are similar to those of bacterial methane, but their chemical compositions do not exhibit the dry character in comparison with biogenic gases. These characteristics of deep gas inclusions may be related to the migration fractionation. Some deep natural gases with light carbon isotopic characteristics in the Tazhong Uplift may have a similar origin. The δ13C1 values of gas inclusions in Lower Cambrian rocks (7117-7124 m) are heavier (-39‰), consistent with highly mature natural gases. Carbon isotopic compositions of CO2 in the gas inclusions of deep carbonate rocks are similar (from -4‰ to -13‰) to those of deep natural gases, indicating predominantly an inorganic origin.

  6. Geology--hydrology of Avery Island Salt Dome

    Energy Technology Data Exchange (ETDEWEB)

    Jacoby, C.H.

    1977-07-01

    After a review of the geology of the Gulf Coast salt domes, the geology (geomorphology and tectonics) and hydrology of Avery Island Dome, 10 miles south-southwest of New Iberia, Louisiana, were studied in detail. Rock mechanics were studied using grouts and piezometers. 17 figs. (DLC)

  7. Detection of anorthosite rocks on Mars

    Science.gov (United States)

    Carter, J.; Poulet, F.; Flahaut, J.; Ody, A.

    2012-12-01

    The surface of Mars is primarily made up of basaltic (volcanic) rocks comprised of pyroxene, olivine and intermediate felsic plagioclase minerals [e.g. 1,2] and additionally a smaller fraction of sedimentary rocks, at times composed of hydrated salt and clay minerals [3,4]. A few localized eruptive sequences may indicate some compositional evolution from basaltic to dacitic rocks [1], but these remain in essence volcanic rocks. Using the CRISM (Compact Imaging Reconnaissance Spectrometer for Mars) near-infrared imaging spectrometer orbiting Mars [5], we report the detection of a new rock type on Mars, anorthosite. Anorthosite is a highly felsic (>90% plagioclase, 4.3 Gyrs ago [6]. At least 8 anorthosite exposures have been found scattered over the southern highlands of Mars. These are found in the rims of large (D > 50 km) craters or as outcrops in massif units. The unit age for these anorthosite exposures places their formation early in the planet's history (> 4 Gyrs). The massifs exposures are interpreted as deep crustal material uplifted from the Hellas basin forming event [7], which together with the crater rim exposures, suggest a formation at depth in all cases. The preferential co-occurrence of Al-rich clays mixed with several anorthosite exposures also suggests that these rocks were later altered by water at or near the surface. On Mars, there are several reasons to explain why such rocks would not have been formed during its primordial differentiation. In particular, the production of significant quantities of highly differentiated, siliceous melt that would form anorthositic rocks requires specific mechanisms such as fractional crystallization, assimilation, or partial melting of an already evolved source incompatible with the ultramafic source composition inferred for Mars [8,9]. The unforeseen detection of anorthositic-rocks therefore places new and strong constraints on the formation and the evolution of the crust and the mantle of Mars. Two possible

  8. Angiographic and clinical outcomes after implantation of drug eluting stents in bifurcation lesions with crush or kissing stent technique.

    Science.gov (United States)

    Cheema, Asim N; Jolly, Sanjit S; Burstein, Jason M; Sharieff, Waseem; Mohammad, Atif; Yeoh, Eunice; Mancini, G B John; Cantor, Warren J; Kutryk, Michael J B; Strauss, Bradley H; Chisholm, Robert J

    2013-04-01

    Long-term outcome after bifurcation stenting with drug-eluting stents (DES) for obstructive coronary artery disease is poorly understood. In this study, we report 6-9-month angiographic follow-up and long-term clinical outcomes after implantation of drug-eluting stents by crush and kissing stent technique for coronary bifurcation lesions. Consecutive patients undergoing bifurcation stenting with DES by crush or kissing stent technique were enrolled in a prospective registry. Angiographic follow-up was obtained at 6-9 months and clinical follow-up completed for a median of 38 months. A total of 86 patients participated in the study. Bifurcation stenting by crush technique was performed in 73 (85%) and by kissing stent in 13 (15%) patients. Stenting of left main bifurcation was applied in 24 (28%) patients. Angiographic follow-up was completed in 75 (87%) patients and showed restenosis in the main for 8 (11%) and side branch for 20 (27%) patients. Clinical follow-up was available for a median duration of 38 months. During follow-up, 2 (2%) patients died, 4 (5%) experienced myocardial infarction (MI), and 11 (13%) underwent target vessel revascularization (TVR) with an overall major adverse cardiac event (MACE) rate of 16%. In left main cohort, angiographic restenosis occurred in 9 (37%) patients, and 3 (12%) patients required TVR. There were no deaths or stent thrombosis. A comparison of crush and kissing stent technique showed significantly higher angiographic restenosis with crush (26% vs 13% in kissing stent patients, P = 0.046) and 95% of restenosis in crush group involved ostium of the side branch. There was no difference in clinical outcomes between the crush and kissing stent groups. Final kissing balloon dilatation (FKB) was successful in 65 (89%) patients in the crush group and associated with a significant reduction in MACE (8% in FKB successful vs 37% in FKB unsuccessful, P = 0.04) during follow-up. Bifurcation stenting with crush or kissing stent

  9. Mechanical interactions between proppants and rock and their effect on hydraulic fracture performance

    Energy Technology Data Exchange (ETDEWEB)

    Legarth, B.A.; Raab, S.; Huenges, E. [GeoForschungsZentrum Potsdam (Germany)

    2005-07-01

    Proppants interact mechanically with the rock matrix. This causes damage to the fracture face and influences propped fracture performance. Therefore, proppant embedment and proppant crushing phenomena were analysed in laboratory under simulated in situ conditions. The embedment tests were performed in a conductivity cell using reassembled core halves. Embedment features in the rock matrix were optically analyzed. In a separate unit single grain strength tests were performed on a wide range of ceramic proppant types (AI203-based, coated/uncoated) and sizes (diameter 0,2-1,6 mm). The experiment showed that areas in the fracture with low proppant concentration revealed severe proppant crushing and embedment that occurred already at low effective stress. Punctual loading was identified as reason for premature proppant failure. Grain strength testing showed that compressive fracture force increases with grain diameter, is influenced by the presence of a coating and might be additionally controlled by grain surface structure. Compressive fracture strength is largely independent from size for same proppant types. A contact model introduced by Hertz was applied to retrieve the stress magnitudes at grain failure. Proppant crushing leads to generation of fines in the matrix and the proppant pack. These fines can be transported and plug pore-throats and flow channels. Dependent on completion type and expected fracture widths proppant grain size should be maximized for higher fracture conductivity. Proppant crushing and embedment processes are enforced by decreasing proppant concentration. Considering natural conditions in a fracture - rough surfaces, tortuous-twisted paths that hinder even proppant distribution - low proppant concentrations appear to be very real, maybe even the normal case in nature. Thus, high proppant concentration is the key issue to mitigate fracture impairment. (orig.)

  10. ROCK2 is a major regulator of axonal degeneration, neuronal death and axonal regeneration in the CNS.

    Science.gov (United States)

    Koch, J C; Tönges, L; Barski, E; Michel, U; Bähr, M; Lingor, P

    2014-05-15

    The Rho/ROCK/LIMK pathway is central for the mediation of repulsive environmental signals in the central nervous system. Several studies using pharmacological Rho-associated protein kinase (ROCK) inhibitors have shown positive effects on neurite regeneration and suggest additional pro-survival effects in neurons. However, as none of these drugs is completely target specific, it remains unclear how these effects are mediated and whether ROCK is really the most relevant target of the pathway. To answer these questions, we generated adeno-associated viral vectors to specifically downregulate ROCK2 and LIM domain kinase (LIMK)-1 in rat retinal ganglion cells (RGCs) in vitro and in vivo. We show here that specific knockdown of ROCK2 and LIMK1 equally enhanced neurite outgrowth of RGCs on inhibitory substrates and both induced substantial neuronal regeneration over distances of more than 5 mm after rat optic nerve crush (ONC) in vivo. However, only knockdown of ROCK2 but not LIMK1 increased survival of RGCs after optic nerve axotomy. Moreover, knockdown of ROCK2 attenuated axonal degeneration of the proximal axon after ONC assessed by in vivo live imaging. Mechanistically, we demonstrate here that knockdown of ROCK2 resulted in decreased intraneuronal activity of calpain and caspase 3, whereas levels of pAkt and collapsin response mediator protein 2 and autophagic flux were increased. Taken together, our data characterize ROCK2 as a specific therapeutic target in neurodegenerative diseases and demonstrate new downstream effects of ROCK2 including axonal degeneration, apoptosis and autophagy.

  11. Soft rocks in Argentina

    Institute of Scientific and Technical Information of China (English)

    Giambastiani; Mauricio

    2014-01-01

    Soft rocks are a still fairly unexplored chapter in rock mechanics. Within this category are the clastic sedimentary rocks and pyroclastic volcanic rocks, of low to moderate lithification (consolidation, cemen-tation, new formed minerals), chemical sedimentary rocks and metamorphic rocks formed by minerals with Mohs hardness less than 3.5, such as limestone, gypsum, halite, sylvite, between the first and phyllites, graphitic schist, chloritic shale, talc, etc., among the latter. They also include any type of rock that suffered alteration processes (hydrothermal or weathering). In Argentina the study of low-strength rocks has not received much attention despite having extensive outcrops in the Andes and great impact in the design criteria. Correlation between geomechanical properties (UCS, deformability) to physical index (porosity, density, etc.) has shown promising results to be better studied. There are many studies and engineering projects in Argentina in soft rock geological environments, some cited in the text (Chihuído dam, N. Kirchner dam, J. Cepernic Dam, etc.) and others such as International Tunnel in the Province of Mendoza (Corredor Bioceánico), which will require the valuable contribution from rock mechanics. The lack of consistency between some of the physical and mechanical parameters explored from studies in the country may be due to an insufficient amount of information and/or non-standardization of criteria for testing materials. It is understood that more and better academic and professional efforts in improv-ing techniques will result in benefits to the better understanding of the geomechanics of weak rocks.

  12. Rat sciatic nerve crush injury and recovery tracked by plantar test and immunohistochemistry analysis.

    Science.gov (United States)

    Pavić, Roman; Pavić, Michele L; Tvrdeić, Ante; Tot, Ozana K; Heffer, Marija

    2011-01-01

    An experimental crush injury to the sciatic nerve, with a crush force of 49.2 N (pressure p=1.98x10(8) Pa), was inflicted in 30 male rats (Wistar). A control group (sham), with the same number of rats, was also operated upon exactly as the experimental group but without the crush injury. We tested the sensory and motor recovery of the sciatic nerve with Hargreaves method, using an apparatus from Ugo Basile, Italy. Testing was continued for both legs of each rat, injured and uninjured, starting preoperatively (0 day), and then 1, 7, 14, 21, and 28 days postoperatively. The same experiment was run simultaneously with the sham group. The Plantar test showed recovery of the sensory and motor function of the sciatic nerve, though not complete recovery, by 28 days. An immunohistochemical experiment was run in parallel with the plantar test on L3-L6 segments of the spinal cord from where the sciatic nerve extends. We used antibodies for Myelin-associated glycoprotein (MAG), and gangliosides GD1a and GT1b on the aforesaid part of the spinal cord. The immunohistochemical methods showed changes in sensory and motor axons in the spinal cord segment L3-L6 which suggest correspondence with the results of the Plantar test, in terms of recovery of the sensory and motor function after injury of the sciatic nerve. The immunohistochemical results also show ipsilateral and contralateral changes following injury. Results of the plantar test are suggestive that the rat shows compensation for an injury in its contralateral leg.

  13. Dominant inheritance of retinal ganglion cell resistance to optic nerve crush in mice

    Directory of Open Access Journals (Sweden)

    Schlamp Cassandra L

    2007-03-01

    Full Text Available Abstract Background Several neurodegenerative diseases are influenced by complex genetics that affect an individual's susceptibility, disease severity, and rate of progression. One such disease is glaucoma, a chronic neurodegenerative condition of the eye that targets and stimulates apoptosis of CNS neurons called retinal ganglion cells. Since ganglion cell death is intrinsic, it is reasonable that the genes that control this process may contribute to the complex genetics that affect ganglion cell susceptibility to disease. To determine if genetic background influences susceptibility to optic nerve damage, leading to ganglion cell death, we performed optic nerve crush on 15 different inbred lines of mice and measured ganglion cell loss. Resistant and susceptible strains were used in a reciprocal breeding strategy to examine the inheritance pattern of the resistance phenotype. Because earlier studies had implicated Bax as a susceptibility allele for ganglion cell death in the chronic neurodegenerative disease glaucoma, we conducted allelic segregation analysis and mRNA quantification to assess this gene as a candidate for the cell death phenotype. Results Inbred lines showed varying levels of susceptibility to optic nerve crush. DBA/2J mice were most resistant and BALB/cByJ mice were most susceptible. F1 mice from these lines inherited the DBA/2J phenotype, while N2 backcross mice exhibited the BALB/cByJ phenotype. F2 mice exhibited an intermediate phenotype. A Wright Formula calculation suggested as few as 2 dominant loci were linked to the resistance phenotype, which was corroborated by a Punnett Square analysis of the distribution of the mean phenotype in each cross. The levels of latent Bax mRNA were the same in both lines, and Bax alleles did not segregate with phenotype in N2 and F2 mice. Conclusion Inbred mice show different levels of resistance to optic nerve crush. The resistance phenotype is heritable in a dominant fashion involving

  14. Identification of the crushing behavior of brittle foam: From indentation to oedometric tests

    Science.gov (United States)

    Bouterf, A.; Adrien, J.; Maire, E.; Brajer, X.; Hild, F.; Roux, S.

    2017-01-01

    Compaction of the core of plasterboard is one of the limiting phenomena for its mechanical performance. This mechanism is studied herein in an indentation test. A cylinder made of foamed gypsum is indented in situ in an X-ray lab tomograph with a sphere of millimeter radius. The reported experiments show that foamed plaster displays a sharp transition between an undamaged state (with linear elastic behavior) and a compacted state with collapsed porosity under the indenter. Tomographic acquisitions of the sample under load associated with a global version of Digital Volume Correlation allow displacement fields to be measured at different load levels. However, because of the heterogeneous nature of the indentation test, a fine spatial resolution of the displacement fields is required to measure the strains at the crushing limit. A dedicated procedure exploiting computed displacement fields within the digital volume correlation procedure is utilized. It allows for the quantification of stress fields that are post-processed to identify the crushing criterion. It is shown that this analysis is very consistent with more macroscopic oedometric tests. Last, predictions of a Mohr-Coulomb model are compared with macroscopic and microscopic data. It is shown that despite the fact that this model reproduces very well the load-displacement response of the indentation test, a poorer prediction of the experimental crushed zone is observed. In particular, the transition between compacted plaster and its pristine state is not captured by the model, which predicts a very progressive transition rather than an abrupt one. The same conclusions are drawn for a crushable foam model when compared with experimental evidence of an in situ oedometric test.

  15. Case report: Myofascial pain syndrome: a double crush-like appearance

    Science.gov (United States)

    Pringle, R. Kevin; Richardson, Daniel L.; Shiel, Robert S.

    2003-01-01

    Abstract Objective To discuss the case of a patient with myofascial pain syndrome that appeared similar to double crush syndrome. Clinical Features This is a case report of a 45-year old female who presents to the private practice clinic with the same signs and symptoms of carpal tunnel syndrome, 1 year post-carpaltunnel surgery. The history is consistent with injuries that result in double crush syndrome and thoracic outlet syndrome. The patient history includes a motor vehicle accident (MVA) in 1963 that resulted in a prolonged hospital stay and fracture of a cervical vertebral (C4) body. She fractured the olecranon process of the right elbow during a fall in 1970's. She has smoked approximately 1 pack a day for 20 years. Her job involves long periods of sitting at a keyboard and in a car. All of these portions of the patient history are possible factors in the clinical signs and symptoms of double crush syndrome. Intervention and Outcome Treatment involved chiropractic manipulation and physical therapy modalities for the elimination of pain and returning the patient's full range of motion in the wrist, elbow, shoulder and cervical spine. After range of motion was restored, a home exercise program was initiated. The home exercise program included a return to past sporting activity and active, resistive (Theraciser band) activities for the elbow and cervical spine. Also a reduction in smoking was initiated as part of the patient's treatment plan. Conclusion It is our contention that patients who have electromyographic (EMG) demonstrable carpal tunnel syndrome need a cervical spine workup and a period of conservative care to include skilled manipulation, physical therapy and home exercises before surgery is recommended. PMID:19674598

  16. Effect of Zofenopril on regeneration of sciatic nerve crush injury in a rat model

    Directory of Open Access Journals (Sweden)

    Kalender Ali

    2009-06-01

    Full Text Available Abstract Background Zofenopril is an antioxidant agent which has been shown to have beneficial effects in hypertension and heart failure. The aim of this study was to test the effects of Zofenopril on nerve regeneration and scarring in a rat model of peripheral nerve crush injury. Methods Twenty-one adult Sprague-Dawley rats underwent a surgical procedure involving right sciatic nerve crush injury. 15 mg/kg Zofenopril was administered orally to seven rats in group Z for seven days. Seven rats in group S received saline orally for seven days. Seven rats in the control group C received no drug after crush injury. Fourteenth and 42nd days after injury, functional and electromyography assessments of nerves were performed. Functional recovery was analyzed using a walking track assessment, and quantified using the sciatic functional index (SFI. After these evaluations, all rats were sacrificed and microscopic evaluations were performed. Results The Sciatic functional Index (SFI in group Z on 14th day is different significantly from group S and group C (p = 0.037. But on 42nd day there was no difference between groups (p = 0.278. The statistical analyses of electromyelographic (EMG studies showed that the latency in group Z is significantly different from group S (p = 0.006 and group C (p = 0.045. But on 42nd day there was no difference between groups like SFI (p = 0.147. The amplitude was evaluated better in group Z than others (p Conclusion Our results demonstrate that Zofenopril promotes the regeneration of peripheral nerve injuries in rat models.

  17. Trends of Serum Electrolyte Changes in Crush syndrome patients of Bam Earthquake; a Cross sectional Study

    Directory of Open Access Journals (Sweden)

    Saeed Safari

    2017-01-01

    Full Text Available Introduction: Electrolyte imbalances are very common among crushed earthquake victims but there is notenough data regarding their trend of changes. The present study was designed to evaluate the trend of changesin sodium, calcium, and phosphorus ions among crush syndrome patients. Methods: In this retrospectivecross-sectional study, using the database of Bam earthquake victims, which was developed by Iranian Society ofNephrology following Bam earthquake, Iran, 2003, the 10-day trend of sodium, calcium, and phosphorus ionschanges in > 15 years old crush syndrome patients was evaluated. Results: 118 patients with the mean age of25.6 § 6.9 yearswere studied (57.3 male. On the first day of admission, 52.5% (95% CI: 42.7 - 62.3 of the patientshad hyponatremia, which reached 43.9% (95% CI: 28.5 - 59.3 on day 10. 100.0% of patients were hypocalcemicon admission and serum calcium level did not change dramatically during the 10 days of hospitalization. Theprevalence of hyperphosphatemia on the first day was 90.5% (95% CI: 81.5 - 99.5 and on the 10th day of hospitalization66.7% (95% CI: 48.5 - 84.8 of the patients were still affected. Conclusion: The results of the presentstudy shows the 52.5%prevalence of hyponatremia, 100% hypocalcemia, and 90.5% hyperphosphatemia amongcrush syndrome patients of Bam earthquake victims on the first day of admission. Evaluation of 10-day trendshows a slow decreasing pattern of these imbalances as after 10 days, 43.9% still remain hyponatremic, 92.3%hypocalcemic, and 66.7% hypophosphatemic.

  18. Intraperitoneal Alpha-Lipoic Acid to prevent neural damage after crush injury to the rat sciatic nerve

    Directory of Open Access Journals (Sweden)

    Ozbag Davut

    2009-01-01

    Full Text Available Abstract Objective Crush injury to the sciatic nerve causes oxidative stress. Alfa Lipoic acid (a-LA is a neuroprotective metabolic antioxidant. This study was designed to investigate the antioxidant effects of pretreatment with a-LA on the crush injury of rat sciatic nerve. Methods Forty rats were randomized into four groups. Group I and Group II received saline (2 ml, intraperitoneally and a-LA (100 mg/kg, 2 ml, intraperitoneally in the groups III and IV at the 24 and 1 hour prior to the crush injury. In groups II, III and IV, the left sciatic nerve was exposed and compressed for 60 seconds with a jeweler's forceps. In Group I (n = 10, the sciatic nerve was explored but not crushed. In all groups of rats, superoxide dismutase (SOD and catalase (CAT activities, as well as malondialdehyde (MDA levels were measured in samples of sciatic nerve tissue. Results Compared to Group I, Group II had significantly decreased tissue SOD and CAT activities and elevated MDA levels indicating crush injury (p < 0.05. In the a-LA treatment groups (groups III and IV, tissue CAT and SOD activities were significantly increased and MDA levels significantly decreased at the first hour (p < 0.05 and on the 3rd day (p < 0.05. There was no significant difference between a-LA treatment groups (p > 0.05. Conclusion A-LA administered before crush injury of the sciatic nerve showed significant protective effects against crush injury by decreasing the oxidative stress. A-LA should be considered in the treatment of peripheral nerve injuries, but further studies are needed to explain the mechanism of its neuroprotective effects.

  19. The Formation and Distribution of the Marine Hydrocarbon Source Rock in the Tarim Basin, NW China

    Institute of Scientific and Technical Information of China (English)

    CAI Xiyuan; WANG Yi

    2008-01-01

    There are significant differences in type and distribution between marine source rock and continental source rock. According to the lithology, the Cambrian-Ordovician source rock in the Tarim basin is divided into two types: the carbonate source rock and the mud source rock. The two sets of source rocks are developed mainly in three sets of formations, Lower-Middle Cambrian carbonate source rock and mud source rock, Lower-Middle Ordovician mud source rock and Upper Ordovician lime mud source rock. The stratigraphic and areal distributions of the source rocks are controlled by the altitude and the sedimentary facies respectively. The mud source rock is developed in slope-semi deep sea environment. The source rock developed in the slope sedimentary environment is related with the anoxic environment and the one developed in semi deep sea has a close relationship with the up-flowing sea water. The carbonate source rock is developed mainly in platform slope of highstand systems tract and it is usually intimately associated with the salt rock. The Lower-Middle Cambrian carbonate source rock is developed mainly in the Bachu, Tazhong, Taugguzibasi and Yingmaili areas. The Lower-Middle Cambrian mud source rock is mainly developed in the areas east of the line of Kunan 1-Tadong 1. The Lower-Middle Ordovician mud source rock is developed mainly in the east slope of the Manjiaer depression. The carbonate source rock of Early Ordovician is developed mainly in the platform slope of highstand systems tract, such as the south margin of Tabei, the north slope of Tazhong, the Bachu area and Keping area.

  20. Bullous contact dermatitis caused by self-applied crushed Paederus fuscipes for the treatment of vitiligo.

    Science.gov (United States)

    You, Dong-O; Kang, Jung-Dae; Youn, Nyoung-Hoon; Park, Seok-Don

    2003-11-01

    Paederus dermatitis is a linear, blistering contact dermatitis caused by pederin, a potent vesicant agent that is contained in insects belonging to the genus Paederus. This form of dermatitis usually occurs accidentally in those who have contact with this insect during the summer season. We report a peculiar case of a patient developing severe chemical burnlike lesions after application to her skin of many crushed Paederus fuscipes that she collected from the soil of a riverbank in the early spring for the treatment of her vitiligo.

  1. Edwards's statistical mechanics of crumpling networks in crushed self-avoiding sheets with finite bending rigidity.

    Science.gov (United States)

    Balankin, Alexander S; Flores-Cano, Leonardo

    2015-03-01

    This paper is devoted to the crumpling of thin matter. The Edwards-like statistical mechanics of crumpling networks in a crushed self-avoiding sheet with finite bending rigidity is developed. The statistical distribution of crease lengths is derived. The relationship between sheet packing density and hydrostatic pressure is established. The entropic contribution to the crumpling network rigidity is outlined. The effects of plastic deformations and sheet self-contacts on crumpling mechanics are discussed. Theoretical predictions are in good agreement with available experimental data and results of numerical simulations. Thus, the findings of this work provide further insight into the physics of crumpling and mechanical properties of crumpled soft matter.

  2. Clinical study of lateral patellofemoral crush syndrome caused by military training

    Directory of Open Access Journals (Sweden)

    De-hui ZHANG

    2012-05-01

    Full Text Available Objective  To explore diagnostic method and surgical outcome of lateral patellofemoral crush syndrome caused by military training. Methods  Fifteen patients with lateral patellofemoral crush syndrome caused by military training from May 2006 to May 2008 were enrolled in this study, including 12 men (14 knees and 3 women (3 knees, aged from 22 to 43 years old with an average of 27.3 years. Randomly selected 18 healthy volunteers with similar age and gender but no knee pain symptom were selected to serve as a control group. Anteroposterior and lateral X-ray photographs of knee joint and axial photographs of the patella were taken in both groups for observing the bone architecture of the knee joint and measuring the femoral trochlear angle, patellofemoral congruence angle and patellofemoral index, and the data were compared. The 17 knee joints in patient group were treated with lateral patellar retinaculum release. Then the preoperative and postoperative pain severity was evaluated with visual analogue scale (VAS. Results  Patellofemoral congruence angle was 7.67°± 5.81° and patellofemoral index was 2.49±1.40 in patient group, while they were -2.2°±-2.71° and 1.25±0.15 in control group. The difference between two groups showed statistical significance (P < 0.05. The change in bone architecture was obvious in patient group. The preoperative pain score was 7.06±0.85, and postoperative pain score was 3.87±0.24 after 6 months and 3.01+0.17 after 1 year in patient group. The difference between preoperative pain score and postoperative pain score showed statistical significance (P < 0.05. Conclusions  Diagnosis of patellofemoral crush syndrome caused by military training requires a combination of case history, typical symptoms, objective sign and X-ray examination. Among these, X-ray examination is the fundamental auxiliary diagnostic tool for lateral patellofemoral crush syndrome, and the patellofemoral index is convenient for

  3. Study on the Elasticity-Plasticity-Stickiness of the Railway Crushed Stone Ballast

    Institute of Scientific and Technical Information of China (English)

    Gao Liang

    2004-01-01

    This paper is mainly aimed at the mechanics characteristic elas of ticity-plasticitystickiness existed in the CWR (continuously welded rails) track plane of the railway crushed stone ballast. As an important mechanics parameter of the CWR track plane, the ballast resistance is mainly influenced by this mechanics characteristic. Through the systematic experimental research and the theoretical analysis, this mechanics characteristic of the ballast resistance is revealed and a reasonable theoretical model is built for it. This study set a sound foundation for further studying the CWR track deformation property. It will be beneficial to the development of high-speed railway in China.

  4. A novel wastewater cleaning system for the stone-crushing and sand-making process

    Institute of Scientific and Technical Information of China (English)

    Zhang Wenjun; Li Yanfeng; Tang Jie

    2012-01-01

    The nature of the slurry from the stone-crushing and sand-making processes is analyzed to develop a novel separation process.The process comprises hydro-cyclone separation followed by screening of the fines,clarification,and filtration.Recovering fine sand and clean wastewater for recycle is demonstrated.The +0.045 mm fine sand fraction and-0.045 mm ultra-fine clay in the slurry are separated and recovered.Fine sand that was previously lost and wasted is now recoverable.The cleaned and reused water is as much as 94% of the total.

  5. Topology optimization design of crushed 2D-frames for desired energy absorption history

    DEFF Research Database (Denmark)

    Pedersen, Claus B. Wittendorf

    2004-01-01

    The present work deals with topology optimization for obtaining a desired energy absorption history of a crushed structure. The optimized energy absorbing structures are used to improve the crashworthiness of transportation vehicles. The ground structure consists of rectangular 2D-beam elements...... with plastic hinges. The elements can undergo large rotations, so the analysis accommodates geometric nonlinearities. A quasi-static nonlinear finite element solution is obtained with an implicit backward Euler algorithm, and the analytical sensitivities are computed by the direct differentiation method....

  6. Linking external and internal salt geometries - a key to understanding salt dynamics

    Science.gov (United States)

    Kukla, Peter; Urai, Janos

    2014-05-01

    Considering the growing importance of salt in the energy, food and waste disposal industries, this paper reviews the status quo and major developments in salt research over the last decade. As a way forward in order to close identified gaps in knowledge, an integrated salt basin evaluation concept is proposed appreciating both external and internal geometries and properties. Examples of key studies in the Central European Basin and the South Oman Salt basin show that such a model may improve our understanding of the multi-scale processes operating in salt terrains. The workflow proposed allows to better asses (i) the initiation and maintenance of salt dynamics, (ii) the evolution of the internal structure of evaporites during halokinesis in salt giants, (iii) the coupling of processes in the evaporites and the salt's under- and overburden. It will lead to a better integration of the different data sets and resulting models, which will provide new insights into the structural evolution of salt giants. Finally it will also stimulate new concepts for (i) the initiation dynamics of halokinesis, (ii) the rheology and mechanics of the evaporites by brittle and ductile processes, (iii) the coupling of processes in the evaporites and the under- and overburden, and (iv) the impact of the layered evaporite rheology on the structural evolution. As an outlook for future research to be initiated in salt terrains we still need to improve our database on evaporite rocks especially the ones which take changes of properties in time into account. This includes for example the dependencies of thermal and mechanical properties on changes in strain, pressure and temperature or external and internal geometry changes relating to slow geological processes. Also geomechanical modelling efforts can be significantly improved by making full use of the data available on the effects of water, and some of the discrepancies seen in experimental data on different salts can probably be explained in

  7. Rock Cycle Roulette.

    Science.gov (United States)

    Schmidt, Stan M.; Palmer, Courtney

    2000-01-01

    Introduces an activity on the rock cycle. Sets 11 stages representing the transitions of an earth material in the rock cycle. Builds six-sided die for each station, and students move to the stations depending on the rolling side of the die. Evaluates students by discussing several questions in the classroom. Provides instructional information for…

  8. Origin of salt giants in abyssal serpentinite systems

    Science.gov (United States)

    Scribano, Vittorio; Carbone, Serafina; Manuella, Fabio C.; Hovland, Martin; Rueslåtten, Håkon; Johnsen, Hans-K.

    2017-03-01

    Worldwide marine salt deposits ranging over the entire geological record are generally considered climate-related evaporites, derived from the precipitation of salts (mainly chlorides and sulfates) from saturated solutions driven by solar evaporation of seawater. This explanation may be realistic for a salt thickness ≤100 m, being therefore inadequate for thicker (>1 km) deposits. Moreover, sub-seafloor salt deposits in deep marine basins are difficult to reconcile with a surface evaporation model. Marine geology reports on abyssal serpentinite systems provide an alternative explanation for some salt deposits. Seawater-driven serpentinization consumes water and increases the salinity of the associated aqueous brines. Brines can be trapped in fractures and cavities in serpentinites and the surrounding `country' rocks. Successive thermal dehydration of buried serpentinites can mobilize and accumulate the brines, forming highly saline hydrothermal solutions. These can migrate upwards and erupt onto the seafloor as saline geysers, which may form salt-saturated water pools, as are currently observed in numerous deeps in the Red Sea and elsewhere. The drainage of deep-seated saline brines to seafloor may be a long-lasting, effective process, mainly occurring in areas characterized by strong tectonic stresses and/or igneous intrusions. Alternatively, brines could be slowly expelled from fractured serpentinites by buoyancy gradients and, hence, separated salts/brines could intrude vertically into surrounding rocks, forming salt diapirs. Serpentinization is an ubiquitous, exothermic, long-lasting process which can modify large volumes of oceanic lithosphere over geological times. Therefore, buried salt deposits in many areas of the world can be reasonably related to serpentinites.

  9. Mobility promotes and jeopardizes biodiversity in rock-paper-scissors games

    CERN Document Server

    Reichenbach, Tobias; Frey, Erwin

    2008-01-01

    Biodiversity is essential to the viability of ecological systems. Species diversity in ecosystems is promoted by cyclic, non-hierarchical interactions among competing populations. Such non-transitive relations lead to an evolution with central features represented by the `rock-paper-scissors' game, where rock crushes scissors, scissors cut paper, and paper wraps rock. In combination with spatial dispersal of static populations, this type of competition results in the stable coexistence of all species and the long-term maintenance of biodiversity. However, population mobility is a central feature of real ecosystems: animals migrate, bacteria run and tumble. Here, we observe a critical influence of mobility on species diversity. When mobility exceeds a certain value, biodiversity is jeopardized and lost. In contrast, below this critical threshold all subpopulations coexist and an entanglement of travelling spiral waves forms in the course of temporal evolution. We establish that this phenomenon is robust, it do...

  10. Numerical Analysis of Effect of Water on Explosive Wave Propagation in Tunnels and Surrounding Rock

    Institute of Scientific and Technical Information of China (English)

    XIA Chang-jing; SONG Zhen-duo; TIAN Lu-lu; LIU Hong-bin; WANG Lu; WU Xiao-fang

    2007-01-01

    Based on the application of practical engineering, propagation processes of explosive waves in rock with water well and tunnel are simulated by ANSYS/LS-DYNA software. The evolution of damage in rock is presented. The effect of water on the damage of the concrete slab in a tunnel is compared with damage inflicted without water. The numerical simulation illustrates that water plays an important role in the evolution of damage of the concrete slab in a mine tunnel. In the presence of water in the rock the concrete slab is damaged more severely than without water in rock. The effect of water location in the rock is also considered. It is found that the concrete slab in the tunnel shows various degrees of damage as a function of the different locations of water. Attenuation laws of stress waves over time-space in rock with water are also obtained. Numerical results indicate that, under blast loading, there are three zones in the rock: a crushed zone nearby the explosive charge, a damaged zone and an elastic zone. The conclusions of numerical analysis may provide references for blasting designs and structure protection.

  11. SALT DAMAGE CRITERION PROOF-OF-CONCEPT RESEARCH

    Energy Technology Data Exchange (ETDEWEB)

    Kerry L. DeVries; Kirby D. Mellegard; Gary D. Callahan

    2002-11-01

    The purpose of this study was to conduct a field-scale application demonstrating the use of continuum damage mechanics to determine the minimum allowable operating pressure of compressed natural gas storage caverns in salt formations. A geomechanical study was performed of two natural gas storage caverns (one existing and one planned) utilizing state-of-the-art salt mechanics to assess the potential for cavern instability and collapse. The geomechanical study consisted primarily of laboratory testing, theoretical development, and analytical/numerical tasks. A total of 50 laboratory tests was performed on salt specimens to aid in the development and definition of the material model used to predict the behavior of rock salt. Material model refinement was performed that improved the predictive capability of modeling salt during damage healing, recovery of work-hardened salt, and the behavior of salt at stress states other than triaxial compression. Results of this study showed that the working gas capacity of the existing cavern could be increased by 18 percent and the planned cavern could be increased by 8 percent using the proposed method compared to a conventional stress-based method. Further refinement of the continuum damage model is recommended to account for known behavior of salt at stress conditions other than triaxial compression that is not characterized accurately by the existing model.

  12. Physical model test on operational safety of injection and recovery casing of underground salt rock gas storages%盐岩地下储气库注采气套管运行安全的物理模型试验研究

    Institute of Scientific and Technical Information of China (English)

    段抗; 张强勇; 向文; 蔡兵; 许孝滨; 贾超; 刘健

    2013-01-01

    注采气套管结构是保证盐岩地下储气库注采气正常运行的重要枢纽,在盐岩地下储气库运行过程中,套管混凝土环极易因储库蠕变体积收缩而产生受拉破坏.因此,为了解套管混凝土环的受力和变形特性,采用三维地质力学模型试验技术,对江苏金坛盐岩地下储气库开展了不同采气速率、不同采气内压、储库失压等风险因素影响下的套管运行过程的物理模型试验,通过三维地质力学模型试验较好反映出储气库套管混凝土环的受力和变形特性.研究表明:(1)套管混凝土环的轴向拉应变随采气速率的增加而增大,为保证套管的运行安全,建议储气库的最大采气速率不超过0.65 MPa/d; (2)套管混凝土环的轴向拉应变和套管所受蠕变挤压应力随套管鞋离腔顶距离的减小而增大,为保证储气库运行安全,套管底部距离储库腔顶的距离应大于10m:(3)套管所受蠕变挤压应力随采气内压的减小而显著增大,储气库的最低运行气压应大于3 MPa,并应最大限度地防止储气库出现失压事故.%The gas injection and recovery casing structure is an important hub to ensure the normal operation of underground salt rock gas storage.During the operation of gas storages,the casing concrete is vulnerable to tensile failure because of the volume contraction caused by creep.Therefore,in order to understand the mechanical and deformational characteristics of the casing cement ring,the three-dimensional geomechanical model test technology is adopted and the physical model test on operation process of Jintan salt rock gas storage casing under the influences of different risk factors including different gas recovery rates,different gas production pressures and cavern pressure loss is carried out.The 3-D geomechanical model test can reflect the mechanical and deformational characteristics of the concrete ring of gas storage casing better.The results show that:(1) the

  13. Diversity of Extremely Halophilic Archaeal and Bacterial Communities from Commercial Salts

    Directory of Open Access Journals (Sweden)

    Ashagrie Gibtan

    2017-05-01

    Full Text Available Salting is one of the oldest food preservation techniques. However, salt is also the source of living halophilic microorganisms that may affect human health. In order to determine the microbial communities of commercial salts, an investigation were done using amplicon sequencing approach in four commercial salts: Ethiopian Afdera salt (EAS, Ethiopian rock salt (ERS, Korean Jangpan salt (KJS, and Korean Topan salt (KTS. Using domain-specific primers, a region of the 16S rRNA gene was amplified and sequenced using a Roche 454 instrument. The results indicated that these microbial communities contained 48.22–61.4% Bacteria, 37.72–51.26% Archaea, 0.51–0.86% Eukarya, and 0.005–0.009% unclassified reads. Among bacteria, the communities in these salts were dominated by the phyla Proteobacteria, Bacteroidetes, Actinobacteria, and Firmicutes. Of the archaea, 91.58% belonged to the class Halobacteria, whereas the remaining 7.58, 0.83, and 0.01% were Nanoarchaea, Methanobacteria, and Thermococci, respectively. This comparison of microbial diversity in salts from two countries showed the presence of many archaeal and bacterial genera that occurred in salt samples from one country but not the other. The bacterial genera Enterobacter and Halovibrio were found only in Korean and Ethiopian salts, respectively. This study indicated the occurrence and diversity of halophilic bacteria and archaea in commercial salts that could be important in the gastrointestinal tract after ingestion.

  14. Immune system augmentation by glatiramer acetate of peripheral nerve regeneration-crush versus transection models of rat sciatic nerve.

    Science.gov (United States)

    Luria, Shai; Cohen, Avraham; Safran, Ori; Firman, Shimon; Liebergall, Meir

    2013-10-01

    Immune system augmentation, using the antigen glatiramer acetate (GA), which is known to affect cellular immunity, has been shown to have a positive effect on peripheral nerve regeneration. We aimed to compare the effect of GA on the regeneration of crushed versus transected nerves. Wild-type rats underwent crush or transection and repair of the sciatic nerve. They were examined 3 weeks postinjury histologically (axon count) and functionally (tibialis anterior muscle weight and footprint analysis). GA was found to augment regeneration both histologically and functionally. In the transected nerve, a significant increase in axon count distal to the injury site was seen in the GA group versus control. A similar yet statistically insignificant trend was found in the crushed nerve. Improvement was found in the footprint analysis between the GA and control groups in both crush and transected nerve groups. We found improvement in the footprint analysis in the crush versus transection group. GA was found to improve the regeneration of the peripheral nerve. Histologically, this was more pronounced in the transection injury. The discrepancy between the different functional measures examined may be explained by the distance of the reinnervated muscles evaluated from the injury site. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  15. Development of a system for receiving, crushing and screening recycled fuel (REF) material; Kierraetyspolttoaineen vastaanotto-, murskaus- ja seulontajaerjestelmaen kehittaeminen

    Energy Technology Data Exchange (ETDEWEB)

    Nurmi, A. [VTT Energy, Jyvaeskylae (Finland)

    1997-12-01

    The goal of this project is to develop a system to which source sorted combustible industrial, office and municipal waste material can be taken and where it is then processed in such way that it can be burnt in modern fluidized bed and circulating bed boilers. The project started in the end of year 1995. The main stages of the project are: (1) Study and analysis of existing technology and equipment, (2) Development of system components, (3) Development of the system, (4) Building a pilot/demonstration plant, (5) Tests and results analysis and (6) Decisions on further actions. In the year 1996 the main stage was development of system components; especially crushing. Results of running slow-speed big crushers were collected, analysed and the main development details determined. Additionally, particle size distribution from different crushing methods were analyzed using also primary and secondary crushing. Development of a heavy-duty 2-rotor ECO-Crusher and a crushing screen was started. Regarding to the development of the REF-system, different alternatives have been analyzed and possible demonstration places have been searched. The first multi-crushing line will be demonstrated in Sweden. (orig.)

  16. SALT for Language Acquisition.

    Science.gov (United States)

    Bancroft, W. Jane

    1996-01-01

    Discusses Schuster's Suggestive-Accelerative Learning Techniques (SALT) Method, which combines Lozanov's Suggestopedia with such American methods as Asher's Total Physical Response and Galyean's Confluent Education. The article argues that students trained with the SALT Method have higher achievement scores and better attitudes than others. (14…

  17. Hydroxycarboxylic acids and salts

    Energy Technology Data Exchange (ETDEWEB)

    Kiely, Donald E; Hash, Kirk R; Kramer-Presta, Kylie; Smith, Tyler N

    2015-02-24

    Compositions which inhibit corrosion and alter the physical properties of concrete (admixtures) are prepared from salt mixtures of hydroxycarboxylic acids, carboxylic acids, and nitric acid. The salt mixtures are prepared by neutralizing acid product mixtures from the oxidation of polyols using nitric acid and oxygen as the oxidizing agents. Nitric acid is removed from the hydroxycarboxylic acids by evaporation and diffusion dialysis.

  18. SALT for Language Acquisition.

    Science.gov (United States)

    Bancroft, W. Jane

    1996-01-01

    Discusses Schuster's Suggestive-Accelerative Learning Techniques (SALT) Method, which combines Lozanov's Suggestopedia with such American methods as Asher's Total Physical Response and Galyean's Confluent Education. The article argues that students trained with the SALT Method have higher achievement scores and better attitudes than others. (14…

  19. DK crush technique: modified treatment of bifurcation lesions in coronary artery

    Institute of Scientific and Technical Information of China (English)

    CHEN Shao-liang; GE Jun-bo; YE Fei; ZHANG Jun-jie; ZHU Zhong-sheng; LIN Song; SHAN Shou-jie; LIU Zhi-zhong; LIU Yan; DUAN Bao-xiang

    2005-01-01

    @@ Bifurcation lesions are still technically challenging even in the era of modern stents.1 High incidence of restenosis both in main vessel and side branch limits the long-term prognosis although several kinds of techniques have been identified to be successful for coronary bifurcations.2-5 Reports have demonstrated the main reason for higher incidence of ostial side branch even though drug-eluting stent used in side vessel lies in that there were gaps in metal coverage and drug application.6-9 Therefore, new technique ensuring complete vessel scaffolding without gaps in drug delivery at the bifurcation is crush technique which is similar to other techniques including T- and Y- stenting still needing postdilatation of kissing balloon angioplasty to expand the stent fully in the ostial side branch and to prevent stent distortion in main vessel.10 As a result, kissing balloon angioplasty is a key step to improve the final result and to reduce the restenosis after stenting bifurcation lesions. However, kissing angioplasty is difficult to be underwent or impossible because operators usually fail to rewire two layers of metal strut, which would result in suboptimal stent deployment, a main reason of high incidence of restenosis, and acute- or-late-thrombosus. The present study reports modified DK crush technique improving success rate of kissing balloon angioplasty under the guidance of intravascular ultrasound (IVUS).

  20. Successful salvage of the upper limb after crush injury requiring nine operations: a case report.

    Science.gov (United States)

    Zeng, Qingmin; Cai, Guoping; Liu, Dechang; Wang, Kun; Zhang, Xinchao

    2015-03-01

    Emergency treatment of amputation is one of the most frequently used therapeutic methods for patients with severe upper limb crush injury with a mangled extremity severity score (MESS) of more than 7. With the development of advanced surgical repair techniques and reconstructive technology, cases that once required amputation can now be salvaged with appropriate management, and some limb functions may also be reserved. A patient with a severe upper limb crush injury with a MESS score of 10 was treated in our hospital. The limb was salvaged after 9 surgeries over 10 months. The follow-up visits over the next 18 months post-injury showed that the shoulder joint functions were rated as "excellent" (90) according to the Neer score, the Harris hip evaluation (HHS) for elbow joint functions was "good" (80), and the patient was very satisfied with the overall therapeutic outcome. We conclude from the successful outcome of this extreme injury that salvage attempts should be the first management choice for upper limbs with complex injuries to save as much function as possible. Amputation should only be adopted when the injury is life-threatening or no more function can be saved. The level of evidence was V.

  1. Infectious complications in patients with crush syndrome following the Wenchuan earthquake

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hui; ZENG Jian-wei; WANG Guang-lin; TU Chong-qi; HUANG Fu-guo; PEI Fu-xing

    2013-01-01

    Objective:To analyze the results of clinical and bacteriological examinations in patients with crash syndrome who suffered infectious complications after an earthquake in Sichuan,China.Methods:A total of 313 bacteriological samples among 147 patients with crush syndrome were collected.Infectious complications,results of microbiological examinations,potential risk factors of infection and mortality were analyzed statistically.Results:In the obtained database,112 out of the 147 (75.7%) patients had infectious complications,in which,wound infection,pulmonary infection,and sepsis were most common.The time under the rubble and the time from injury to treatment were related to the occurrence of wound infection (P=0.013,odds ratio 2.25; P=0.017,odds ratio 2.31).Sepsis and wound infection were more common in patients who underwent fasciotomy or amputation than in those who did not (P=0.001).Conclusion:Quick rescue and injury treatment can decrease the infection risk in crush syndrome patients.It is better to obtain microorganic proofs before applying antibiotics,and bacteriological and drug sensitivity data should be taken into account,especially considering that most of these infections are hospital-acquired and drug resistance.Emphasizing the accuracy and efficiency of wound management in emergency situations,cautiously assessing the indications for fasciotomy to avoid open wounds from unnecessary osteofascial compartment decompression incisions may decrease the incidence of infection and ameliorate the prognosis.

  2. Numerical Investigation on Dynamic Crushing Behavior of Auxetic Honeycombs with Various Cell-Wall Angles

    Directory of Open Access Journals (Sweden)

    Xin-chun Zhang

    2015-02-01

    Full Text Available Auxetic honeycombs have proven to be an attractive advantage in actual engineering applications owing to their unique mechanical characteristic and better energy absorption ability. The in-plane dynamic crushing behaviors of the honeycombs with various cell-wall angles are studied by means of explicit dynamic finite element simulation. The influences of the cell-wall angle, the impact velocity, and the edge thickness on the macro/microdeformation behaviors, the plateau stresses, and the specific energy absorption of auxetic honeycombs are discussed in detail. Numerical results show, that except for the impact velocity and the edge thickness, the in-plane dynamic performances of auxetic honeycombs also rely on the cell-wall angle. The “> <”-mode local deformation bands form under low- or moderate-velocity impacting, which results in lateral compression shrinkage and shows negative Poisson's ratio during the crushing. For the given impact velocity, the plateau stress at the proximal end and the energy-absorbed ability can be improved by increasing the negative cell angle, the relative density, the impact velocity, and the matrix material strength. When the microcell parameters are the constant, the plateau stresses are proportional to the square of impact velocity.

  3. Dissolution of Intact, Divided and Crushed Circadin Tablets: Prolonged vs. Immediate Release of Melatonin

    Directory of Open Access Journals (Sweden)

    Hui Ming Chua

    2016-01-01

    Full Text Available Circadin 2 mg prolonged-release tablet is the only licensed melatonin product available in the UK. Circadin is indicated for patients with primary insomnia aged 55 and over, but is more widely used “off-label” to treat sleep disorders especially in the paediatric population. Children and older people often have difficulty swallowing tablets and dividing the tablet is sometimes required to ease administration. The aim of this study was to measure the release profile of melatonin from Circadin tablets when divided or crushed, and compare this with release from intact tablets. Dissolution testing was also performed for unlicensed melatonin products for comparison. Dissolution tests were performed using the pharmacopoeial paddle apparatus, with melatonin release analyzed by high performance liquid chromatography. Melatonin content, hardness, friability, and disintegration of the products were also evaluated. The prolonged release of melatonin from Circadin tablets was unlike that of any other product tested. When divided into halves, Circadin preserved most of the prolonged-release characteristic (f2 = 58, whereas quarter-cut and crushed tablet had a more immediate melatonin release profile. Circadin is significantly less expensive and should be preferred to unlicensed medicines which are not pharmaceutically equivalent and offer less quality assurance.

  4. Evaluation of a method based on image analysis to obtain shape parameters in crushed sand grains

    Directory of Open Access Journals (Sweden)

    A. G. Goldoni

    Full Text Available ABSTRACTThe objective of this paper is to evaluate a method based on image analysis to obtain shape parameters in crushed sand grains. There is no consensus about standards and rules for testing aggregates, the lack of methodology to prepare and conduct tests may produce incorrect results, which do not satisfactorily represent the aggregate characteristics. One way to perform these analyzes is the use of images obtained with magnifying glasses or similar equipment. To contribute to this, three experiments were prepared with samples of crushed sand from the city of Passo Fundo. The fixed and evaluated parameters were: samples preparation, zoom used for image acquisition and number of grains representative of the shape parameters. The results were statistically analyzed and significant differences were obtained to the shape factor regarding the fixed parameters, except for the number of grains needed to characterize it, which differs from the currently literature used by academic studies. According to this work it is possible to realize that it is necessary to standardize the tests for shape analysis to eliminate errors generated by the interpretation of incorrect results, which may have been generated by changes in the methodology for conducting the tests.

  5. Effect of Crushed Air-cooled Blast Furnace Slag on Mechanical Properties of Concrete

    Institute of Scientific and Technical Information of China (English)

    WANG Aiguo; DENG Min; SUN Daosheng; LI Bing; TANG Mingshu

    2012-01-01

    Morphology characteristics of mix aggregates with crushed air-cooled blast furnace slag (SCR) and crushed limestone (LCR) with 5-20 mm and 20-40 mm gradation were represented by numerical parameters including angularity number (AN) and index of aggregate particle shape and texture (IAPST).The effect of mix aggregates containing SCR on compressive strength and splitting tensile strength of concrete was investigated.Fracture characteristics of concrete,interfacial structure between aggregates and matrix were analyzed.The experimental results show that porous and rough SCR increases contact area with matrix in concrete,concave holes and micro-pores on the surface of SCR are filled by mortar and hydrated cement paste,which may increase interlocking and mechanical bond between aggregate and matrix in concrete.SCR can be used to produce a high-strength concrete with better mechanical properties than corresponding concrete made with LCR.The increase of AN and IAPST of aggregate may enhance mechanical properties of concrete.

  6. Fatigue Crack Propagation in Steel A131 Under Ice Loading of Crushing, Bending and Buckling

    Institute of Scientific and Technical Information of China (English)

    DUAN Menglan(段梦兰); SONG Lisong(宋立崧); FAN Xiaodong(樊晓东); James C.M.LId; FANG Huacan(方华灿)

    2001-01-01

    Three types of ice loading, which are most commonly present when ice acts on structures,are chosen and simulated for use of fatigue crack propagation tests on offshore structural steel Al31. The three types of ice categorized in accordance with the failure modes when acting on structures called crushing ice, bending ice, and buckling ice,respectively. This paper presents an experimental investigation on the fatigue crack propagation behavior of widely used high strength steel A 131 for offshore jackets in the loading environment of ice crushing, bending, and buckling. The test results of fatigue crack propagation in steel A 13 l under these simulated ice loading at temperature 292K are presented and analyzed in detail in this paper. The amplitude root mean square stress intensity factor is optimized to be the fundamental parameter of fatigue crack propagation for all types of ice loading histories. The results are also compared with constant amplitude fatigue crack propagation conclusions as in wave load mode, and a joint investigation on the results from ice forces, ice-induced vibrations, and ice-induced fatigue crack propagation is conducted, Conclusions are drawn for reference in structural design and material selection for offshore structures in ice environments.

  7. The Influence of Crushed Concrete Demolition Waste Aggregates on the Hardening Process of Concrete Mixtures

    Directory of Open Access Journals (Sweden)

    Olga FINOŽENOK

    2013-03-01

    Full Text Available Concrete – complex structure composite material consisting of the components with various structure and size. Not only coarse and fine aggregates are used in concrete production, but also filler aggregates. Aggregates of natural, man-made origin or aggregates, produced from recycled materials, can be utilised in concrete production. Aggregates can be produced from recycled materials by reprocessing of concrete and reinforced concrete waste. The influence of the filler aggregates produced from the crushed concrete waste on the characteristics of binder’s paste, when part of the binder (5; 10; 15; 20; 25; 30 % is replaced by such filler aggregate, is analysed in the research. Concrete mixtures with natural aggregates and crushed concrete waste were selected and concrete mixtures of required consistence were produced during the research. Exothermic reactions take place during the hardening of concrete mixture, at that time the heat is dissipated, which increases the temperature of the concrete sample. Thus the exothermic processes were investigated during the concrete’s mixture hardening period and the temperatures of exothermic reactions were determined.DOI: http://dx.doi.org/10.5755/j01.ms.19.1.3833

  8. On the effect of marrow in the mechanical behavior and crush response of trabecular bone.

    Science.gov (United States)

    Halgrin, J; Chaari, F; Markiewicz, É

    2012-01-01

    The present paper focuses on the mechanical behavior analysis of bones at mesoscopic scale, paying a special attention to the trabecular bone and the bone marrow filling the porosities. Uni-axial quasi-static compression tests under unconfined conditions have been performed to identify the mechanical behavior of 46 trabecular bone samples. The bone marrow for 22 samples has been preserved to analyze the fluid flow effects on the crushing response. Although deformation patterns do not differ significantly, the average crush behavior of the trabecular bone shows an unexpected decrease of the mechanical properties when the marrow is kept in the sample (26% for the elastic modulus (E(a)), 38% for the maximum compressive stress (σ(max)) and 33% for the average stress (σ(mean))). An explanation is given by analyzing the contribution of the bone marrow viscosity which smooths the mechanical response. A numerical analysis on an idealized trabecula confirms that the marrow induces transverse pressure and extra local stress on trabeculae during its flow, causing the premature collapse of the trabecular network. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Salt repository project closeout status report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1988-06-01

    This report provides an overview of the scope and status of the US Department of Energy (DOE`s) Salt Repository Project (SRP) at the time when the project was terminated by the Nuclear Waste Policy Amendments Act of 1987. The report reviews the 10-year program of siting a geologic repository for high-level nuclear waste in rock salt formations. Its purpose is to aid persons interested in the information developed during the course of this effort. Each area is briefly described and the major items of information are noted. This report, the three salt Environmental Assessments, and the Site Characterization Plan are the suggested starting points for any search of the literature and information developed by the program participants. Prior to termination, DOE was preparing to characterize three candidate sites for the first mined geologic repository for the permanent disposal of high-level nuclear waste. The sites were in Nevada, a site in volcanic tuff; Texas, a site in bedded salt (halite); and Washington, a site in basalt. These sites, identified by the screening process described in Chapter 3, were selected from the nine potentially acceptable sites shown on Figure I-1. These sites were identified in accordance with provisions of the Nuclear Waste Policy Act of 1982. 196 refs., 21 figs., 11 tabs.

  10. Physical and chemical weathering. [of Martian surface and rocks

    Science.gov (United States)

    Gooding, James L.; Arvidson, Raymond E.; Zolotov, Mikhail IU.

    1992-01-01

    Physical and chemical weathering processes that might be important on Mars are reviewed, and the limited observations, including relevant Viking results and laboratory simulations, are summarized. Physical weathering may have included rock splitting through growth of ice, salt or secondary silicate crystals in voids. Chemical weathering probably involved reactions of minerals with water, oxygen, and carbon dioxide, although predicted products vary sensitively with the abundance and physical form postulated for the water. On the basis of kinetics data for hydration of rock glass on earth, the fate of weathering-rind formation on glass-bearing Martian volcanic rocks is tentatively estimated to have been on the order of 0.1 to 4.5 cm/Gyr; lower rates would be expected for crystalline rocks.

  11. Very slow creep tests on salt samples

    Directory of Open Access Journals (Sweden)

    de Greef V.

    2010-06-01

    Full Text Available Long-term creep tests have been performed on rock-salt and argillite samples under very small uniaxial loadings (σ = 0.02 to 0.1 MPa . To minimize the effects of temperature variations, testing devices were set in a mine where temperature fluctuations are of the order of one-hundredth of a degree Celsius. The mechanical loading was provided by dead weights. The deformations were measured through special displacement sensors with a resolution of ∆ε = 10-8. Strain rates as small as έ = 7 × 10-13s-1 were measured. These tests allow rock-sample creep to be investigated at very small strain rates. The tests also prove that extrapolation of constitutive laws at very small rates is often incorrect.

  12. Geomechanics of bedded salt

    Energy Technology Data Exchange (ETDEWEB)

    Serata, S.; Milnor, S.W.

    1979-06-08

    Creep data from the literature search is reinterpreted by SGI, resulting in a better understanding of the temperature and stress state dependence of the octahedral creep rate and the octahedral shear strength. The concept of a transition strength between the elastic and the plastic states is in agreement with the data. The elastic and rheological properties of salt are described, and a set of constitutive equations is presented. The dependence of material properties on parameters such as temperature is considered. Findings on the permeability of salt are summarized, and the in-situ behavior of openings in bedded salt is described based on extensive engineering experience. A stress measuring system utilizing a finite element computer code is discussed. Geological factors affecting the stability of salt openings are considered, and the Stress Control Technique for designing stable openings in bedded salt formations is explained.

  13. Salt Tolerance in Soybean

    Institute of Scientific and Technical Information of China (English)

    Tsui-Hung Phang; Guihua Shao; Hon-Ming Lam

    2008-01-01

    Soybean is an Important cash crop and its productivity is significantly hampered by salt stress. High salt Imposes negative impacts on growth, nodulation, agronomy traits, seed quality and quantity, and thus reduces the yield of soybean. To cope with salt stress, soybean has developed several tolerance mechanisms, including: (I) maintenance of ion homeostasis; (ii) adjustment in response to osmotic stress; (iii) restoration of osmotic balance; and (iv) other metabolic and structural adaptations. The regulatory network for abiotic stress responses in higher plants has been studied extensively in model plants such as Arabidopsis thaliana. Some homologous components involved in salt stress responses have been identified in soybean. In this review, we tried to integrate the relevant works on soybean and proposes a working model to descdbe Its salt stress responses at the molecular level.

  14. Salt and nephrolithiasis.

    Science.gov (United States)

    Ticinesi, Andrea; Nouvenne, Antonio; Maalouf, Naim M; Borghi, Loris; Meschi, Tiziana

    2016-01-01

    Dietary sodium chloride intake is nowadays globally known as one of the major threats for cardiovascular health. However, there is also important evidence that it may influence idiopathic calcium nephrolithiasis onset and recurrence. Higher salt intake has been associated with hypercalciuria and hypocitraturia, which are major risk factors for calcium stone formation. Dietary salt restriction can be an effective means for secondary prevention of nephrolithiasis as well. Thus in this paper, we review the complex relationship between salt and nephrolithiasis, pointing out the difference between dietary sodium and salt intake and the best methods to assess them, highlighting the main findings of epidemiologic, laboratory and intervention studies and focusing on open issues such as the role of dietary salt in secondary causes of nephrolithiasis.

  15. Experimental petrology and origin of rocks from the Descartes Highlands

    Science.gov (United States)

    Walker, D.; Longhi, J.; Grove, T. L.; Stolper, E.; Hays, J. F.

    1973-01-01

    Petrographic studies of Apollo 16 samples indicate that rocks 62295 and 68415 are crystallization products of highly aluminous melts. 60025 is a shocked, crushed and partially annealed plagioclase cumulate. 60315 is a recrystallized noritic breccia of disputed origin. 60335 is a feldspathic basalt filled with xenoliths and xenocrysts of anorthosite, breccia, and anorthite. The Fe/(Fe+Mg) of plagioclase appears to be a relative crystallization index. Low pressure melting experiments with controlled Po2 indicate that the igneous samples crystallized at oxygen fugacities well below the Fe/FeO buffer. Crystallization experiments at various pressures suggest that the 62295 and 68415 compositions were produced by partial or complete melting of lunar crustal materials, and not by partial melting of the deep lunar interior.

  16. CRITERIA FOR ROCK ENGINEERING FAILURE

    Institute of Scientific and Technical Information of China (English)

    ZHUDeren; ZHANGYuzhuo

    1995-01-01

    A great number of underground rock projects are maintained in the rock mass which is subject to rock damage and failure development. In many cases, the rock. engineering is still under normal working conditions even though rock is already fails to some extent. This paper introduces two different concepts: rock failure and rock engineering failure. Rock failure is defined as a mechanical state under which an applicable characteristic is changed or lost.However, the rock engineering failure is an engineering state under which an applicable function is changed or lost. The failure of surrounding rocks is the major reason of rock engineering failure. The criterion of rock engineering failure depends on the limit of applicable functions. The rock engineering failure state possesses a corresponding point in rock failure state. In this paper, a description of rock engineering failure criterion is given by simply using a mechanical equation or expression. It is expected that the study of rock engineering failure criterion will be an optimal approach that combines research of rock mechanics with rock engineering problems.

  17. The Pressure induced by salt crystallization in confinement

    Science.gov (United States)

    Desarnaud, J.; Bonn, D.; Shahidzadeh, N.

    2016-08-01

    Salt crystallization is a major cause of weathering of rocks, artworks and monuments. Damage can only occur if crystals continue to grow in confinement, i.e. within the pore space of these materials, thus generating mechanical stress. We report the direct measurement, at the microscale, of the force exerted by growing alkali halide salt crystals while visualizing their spontaneous nucleation and growth. The experiments reveal the crucial role of the wetting films between the growing crystal and the confining walls for the development of the pressure. Our results suggest that the measured force originates from repulsion between the similarly charged confining wall and the salt crystal separated by a ~1.5 nm liquid film. Indeed, if the walls are made hydrophobic, no film is observed and no repulsive forces are detected. We also show that the magnitude of the induced pressure is system specific explaining why different salts lead to different amounts of damage to porous materials.

  18. The results of cutting disks testing for rock destruction

    Directory of Open Access Journals (Sweden)

    Khoreshok Aleksey

    2017-01-01

    Full Text Available To determine the rational order of disk tools placement on the working body is necessary to know the maximum amount of rock, destroyed by the disk tool in benching cutting mode depending on the tool geometry parameters, physical and mechanical parameters of rocks. The article contains the definition of rational parameters of cutting disk tools as well as power and energy parameters of the destruction process by cutting disks and by executive body of the coal cutter. The rational geometric parameters of cutting discs are specified. It was found that each step of cutting with a minimum depth of penetration has its own maximum height of bench outcrop. The dependence of the volumes of large items destroyed by the disk tool on the cutting step height was determined. The existence of the cyclic alternation of destruction phases, regardless the fracture parameters, the height of the ledge outcrop, and tools like free cutting geometry were found. In contrast to the free cutting in benching mode of destruction two large fragments of rocks in one cycle were observed. Consequently, the cyclical nature of the destruction process in the benching mode will be characterized by two chips and crushing, and this cycling repeats throughout the destruction process with the same parameters of destruction.

  19. Rapid detection of toxic metals in non-crushed oyster shells by portable X-ray fluorescence spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Chou Ju, E-mail: Ju.Chou@selu.ed [Department of Chemistry and Physics, Southeastern Louisiana University, Hammond, LA 70402 (United States); Clement, Garret; Bursavich, Bradley; Elbers, Don [Department of Chemistry and Physics, Southeastern Louisiana University, Hammond, LA 70402 (United States); Cao Baobao; Zhou Weilie [Advanced Material Research Institute, University of New Orleans, New Orleans, LA 70148 (United States)

    2010-06-15

    The aim of this study was the multi-elemental detection of toxic metals such as lead (Pb) in non-crushed oyster shells by using a portable X-ray fluorescence (XRF) spectrometer. A rapid, simultaneous multi-element analytical methodology for non-crushed oyster shells has been developed using a portable XRF which provides a quick, quantitative, non-destructive, and cost-effective mean for assessment of oyster shell contamination from Pb. Pb contamination in oyster shells was further confirmed by scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS). The results indicated that Pb is distributed in-homogeneously in contaminated shells. Oyster shells have a lamellar structure that could contribute to the high accumulation of Pb on oyster shells. - A rapid, simultaneous multi-element analytical methodology for non-crushed oyster shells has been developed using XRF and contamination of lead on oyster shells was confirmed by XRF and SEM-EDS.

  20. Quasi-Static Crushing Simulation Research and Failure Mode Analysis of Composite Thin-Walled C-Channel Specimen

    Directory of Open Access Journals (Sweden)

    XIE Jiang

    2017-04-01

    Full Text Available To study the crushing energy-absorbing characteristics and failure mode, the multi-shells finite element model of composite thin-walled C-channel specimen was established based on the quasi-static crushing test results. The simulation results show that the delamination failure, local buckling and beam bending failure of C-channel specimen can be simulated with the multi-shells finite element model. The load-displacement curve well fits the test results, and the deviation of initial peak load (Fmax, specific energy absorption (Es and crushing mean load (Fmean is small compared with the test results. The initial peak load of C-channel specimen is larger and the load efficiency is lower, so it is necessary to further reduce the initial peak load by the design optimization.

  1. Low-Level Laser Irradiation Improves Functional Recovery and Nerve Regeneration in Sciatic Nerve Crush Rat Injury Model

    Science.gov (United States)

    Wang, Chau-Zen; Chen, Yi-Jen; Wang, Yan-Hsiung; Yeh, Ming-Long; Huang, Mao-Hsiung; Ho, Mei-Ling; Liang, Jen-I; Chen, Chia-Hsin

    2014-01-01

    The development of noninvasive approaches to facilitate the regeneration of post-traumatic nerve injury is important for clinical rehabilitation. In this study, we investigated the effective dose of noninvasive 808-nm low-level laser therapy (LLLT) on sciatic nerve crush rat injury model. Thirty-six male Sprague Dawley rats were divided into 6 experimental groups: a normal group with or without 808-nm LLLT at 8 J/cm2 and a sciatic nerve crush injury group with or without 808-nm LLLT at 3, 8 or 15 J/cm2. Rats were given consecutive transcutaneous LLLT at the crush site and sacrificed 20 days after the crush injury. Functional assessments of nerve regeneration were analyzed using the sciatic functional index (SFI) and hindlimb range of motion (ROM). Nerve regeneration was investigated by measuring the myelin sheath thickness of the sciatic nerve using transmission electron microscopy (TEM) and by analyzing the expression of growth-associated protein 43 (GAP43) in sciatic nerve using western blot and immunofluorescence staining. We found that sciatic-injured rats that were irradiated with LLLT at both 3 and 8 J/cm2 had significantly improved SFI but that a significant improvement of ROM was only found in rats with LLLT at 8 J/cm2. Furthermore, the myelin sheath thickness and GAP43 expression levels were significantly enhanced in sciatic nerve-crushed rats receiving 808-nm LLLT at 3 and 8 J/cm2. Taken together, these results suggest that 808-nm LLLT at a low energy density (3 J/cm2 and 8 J/cm2) is capable of enhancing sciatic nerve regeneration following a crush injury. PMID:25119457

  2. Cytidine 5′-diphosphocholine administration prevents peripheral neuropathic pain after sciatic nerve crush injury in rats

    Science.gov (United States)

    Emril, Dessy R; Wibowo, Samekto; Meliala, Lucas; Susilowati, Rina

    2016-01-01

    Background Cytidine 5′-diphosphocholine (citicoline) has been shown to have beneficial effects in central nervous system injury as well as in motoric functional recovery after peripheral nerve injury. This study aimed to examine the effect of citicoline on prevention of neuropathic pain in a rat model of sciatic nerve crush injury. Methods Forty experimental rats were divided into four groups. In three groups, the right sciatic nerves were crushed in the mid-thigh region, and a gelatin sponge moistened with 0.4 or 0.8 mL of 100 µmol/L citicoline, or saline 0.4 mL in the control group, was applied. The fourth group of rats was sham-operated, ie the sciatic nerve was exposed with no crush. Functional assessments were performed 4 weeks after crush injury. von Frey filaments (100 g threshold) were used to assess neuropathic pain. In addition, the sciatic functional index and extensor postural thrust (EPT) tests were used to assess motoric function. Results The crush/citicoline 0.4 mL group had a lower percentage of pain (23.53%, n=17) compared with the crush/saline group (53.33%, n=15, Pciticoline 0.4 mL group also showed better motoric recovery, as seen in stronger EPT results (Pciticoline 0.8 mL group showed a higher percentage of pain (66.67%, n=18) and less EPT recovery. These results may be explained by more severe nerve injury due to compression with a larger administered volume. Conclusion In situ administration of 0.4 mL of 100 µmol/L citicoline prevents the occurrence of neuropathic pain and induces motoric recovery, evaluated by EPT test, 4 weeks after sciatic nerve injury. PMID:27284264

  3. Days of Rock

    Institute of Scientific and Technical Information of China (English)

    YUAN

    2004-01-01

    FROM last October 1 st to 3rd, at the foot of Fragrant Hill, a suburban Beijing resort famous for its flaming maple leaves in autumn, more than 20,000 rock fans indulged themselves in music for three days.

  4. Writing Rock Music Reviews.

    Science.gov (United States)

    Brown, Donal

    1980-01-01

    Suggests ways student reviewers of rock music groups can write better reviews. Among the suggestions made are that reviewers occasionally discuss the audience or what makes a particular group unique, support general comment with detail, and avoid ecstatic adjectives. (TJ)

  5. Rock kinoekraanil / Katrin Rajasaare

    Index Scriptorium Estoniae

    Rajasaare, Katrin

    2008-01-01

    7.-11. juulini kinos Sõprus toimuval filminädalal "Rock On Screen" ekraanile jõudvatest rockmuusikuid portreteerivatest filmidest "Lou Reed's Berlin", "The Future Is Unwritten: Joe Strummer", "Control: Joy Division", "Hurriganes", "Shlaager"

  6. Art on Rock

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    With sprawling deserts and serene lakes, the natural wonders of Ningxia Hui Autonomous Region have never failed totake the breath away from visitors. The areahas another major attraction, though: the Helan Mountain rock engravings.

  7. Rock kinoekraanil / Katrin Rajasaare

    Index Scriptorium Estoniae

    Rajasaare, Katrin

    2008-01-01

    7.-11. juulini kinos Sõprus toimuval filminädalal "Rock On Screen" ekraanile jõudvatest rockmuusikuid portreteerivatest filmidest "Lou Reed's Berlin", "The Future Is Unwritten: Joe Strummer", "Control: Joy Division", "Hurriganes", "Shlaager"

  8. Pop & rock / Berk Vaher

    Index Scriptorium Estoniae

    Vaher, Berk, 1975-

    2001-01-01

    Uute heliplaatide Redman "Malpractice", Brian Eno & Peter Schwalm "Popstars", Clawfinger "A Whole Lot of Nothing", Dario G "In Full Color", MLTR e. Michael Learns To Rock "Blue Night" lühitutvustused

  9. Pop & rock / Berk Vaher

    Index Scriptorium Estoniae

    Vaher, Berk, 1975-

    2001-01-01

    Uute heliplaatide Redman "Malpractice", Brian Eno & Peter Schwalm "Popstars", Clawfinger "A Whole Lot of Nothing", Dario G "In Full Color", MLTR e. Michael Learns To Rock "Blue Night" lühitutvustused

  10. Art on Rock

    Institute of Scientific and Technical Information of China (English)

    HU YUE

    2010-01-01

    @@ With sprawling deserts and serene lakes, the natural wonders of Ningxia Hui Autonomous Region have never failed to take the breath away from visitors. The area has another major attraction, though: the Helan Mountain rock engravings.

  11. Cytidine 5’-diphosphocholine administration prevents peripheral neuropathic pain after sciatic nerve crush injury in rats

    Directory of Open Access Journals (Sweden)

    Emril DR

    2016-05-01

    Full Text Available Dessy R Emril,1 Samekto Wibowo,2 Lucas Meliala,2 Rina Susilowati3 1Department of Neurology, Faculty of Medicine, Syiah Kuala University, Banda Aceh, 2Department of Neurology, 3Department of Histology and Cell Biology, Faculty of Medicine, Universitas Gadjah Mada, Yogyakarta, IndonesiaBackground: Cytidine 5’-diphosphocholine (citicoline has been shown to have beneficial effects in central nervous system injury as well as in motoric functional recovery after peripheral nerve injury. This study aimed to examine the effect of citicoline on prevention of neuropathic pain in a rat model of sciatic nerve crush injury.Methods: Forty experimental rats were divided into four groups. In three groups, the right sciatic nerves were crushed in the mid-thigh region, and a gelatin sponge moistened with 0.4 or 0.8 mL of 100 µmol/L citicoline, or saline 0.4 mL in the control group, was applied. The fourth group of rats was sham-operated, ie the sciatic nerve was exposed with no crush. Functional assessments were performed 4 weeks after crush injury. von Frey filaments (100 g threshold were used to assess neuropathic pain. In addition, the sciatic functional index and extensor postural thrust (EPT tests were used to assess motoric function.Results: The crush/citicoline 0.4 mL group had a lower percentage of pain (23.53%, n=17 compared with the crush/saline group (53.33%, n=15, P<0.005. The crush/citicoline 0.4 mL group also showed better motoric recovery, as seen in stronger EPT results (P<0.001. However, the sciatic functional index analysis did not show significant differences between groups (P=0.35. The crush/citicoline 0.8 mL group showed a higher percentage of pain (66.67%, n=18 and less EPT recovery. These results may be explained by more severe nerve injury due to compression with a larger administered volume.Conclusion: In situ administration of 0.4 mL of 100 μmol/L citicoline prevents the occurrence of neuropathic pain and induces motoric recovery

  12. Rock avalanches on glaciers

    OpenAIRE

    Shugar, Daniel

    2011-01-01

    This thesis examines relations between rock avalanches and the glaciers on which they are deposited. I have attempted to understand a geophysical phenomenon from two viewpoints: sedimentology and glaciology. The contributions are both methodological, and practical. I have used a GIS to quantify debris sheet geomorphology. A thorough characterization of rock avalanche debris is a necessary step in understanding the flow mechanics of large landslide. I have also developed a technique for solvin...

  13. Evolution of sedimentary rock formation of a rock association level

    Science.gov (United States)

    Kuznetsov, V. G.

    2017-07-01

    The evolution of sedimentary rock formation of a highly organized level (paragenetic rock associations) is more complex than that of a poorly organized level (rocks). Subjacent rock associations are established for the entire geological evolution of the Earth: they varied in time and were obsolescent or, in contrast, nascent and momentary. A certain cyclicity of evolution is identified along with directed changes.

  14. Estimating Rheological Parameters of Anhydrite from Folded Evaporite sequences: Implications for Internal Dynamics of Salt Structure

    Science.gov (United States)

    Adamuszek, Marta; Dabrowski, Marcin; Schmalholz, Stefan M.; Urai, Janos L.; Raith, Alexander

    2015-04-01

    Salt structures have been identified as a potential target for hydrocarbon, CO2, or radioactive waste storage. The most suitable locations for magazines are considered in the thick and relatively homogeneous rock salt layers. However, salt structures often consist of the evaporite sequence including rock salt intercalated with other rock types e.g.: anhydrite, gypsum, potassium and magnesium salt, calcite, dolomite, or shale. The presence of such heterogeneities causes a serious disturbance in the structure management. Detailed analysis of the internal architecture and internal dynamics of the salt structure are crucial for evaluating them as suitable repositories and also their long-term stability. The goal of this study is to analyse the influence of the presence of anhydrite layers on the internal dynamics of salt structures. Anhydrite is a common rock in evaporite sequences. Its physical and mechanical properties strongly differ from the properties of rock salt. The density of anhydrite is much higher than the density of salt, thus anhydrite is likely to sink in salt causing the disturbance of the surrounding structures. This suggestion was the starting point to the discussion about the long-term stability of the magazines in salt structures [1]. However, the other important parameter that has to be taken into account is the viscosity of anhydrite. The high viscosity ratio between salt and anhydrite can restrain the layer from sinking. The rheological behaviour of anhydrite has been studied in laboratory experiments [2], but the results only provide information about the short-term behaviour. The long-term behaviour can be best predicted using indirect methods e.g. based on the analysis of natural structures that developed over geological time scale. One of the most promising are fold structures, the shape of which is very sensitive to the rheological parameters of the deforming materials. Folds can develop in mechanically stratified materials during layer

  15. Comparison of Kuqa foreland basin with Persian Gulf Basin in salt tectonics

    Institute of Scientific and Technical Information of China (English)

    Guimei WAN; Liangjie TANG; Wenzheng JIN

    2007-01-01

    Compared Kuqa foreland basin with Persian Gulf Basin in development of salt layers, salt tectonics, and the relation between salt tectonics and hydrocarbon, it is concluded that the salt diapirs are relative to hydrocarbon. Searching salt diapirs and related traps in Kuqa foreland basin is important. The forming mechanism of salt tectonic in Kuqa foreland basin is different from that of Hormuz Series, but similar to that of Lower Fars Series/Gachsaran Formation. Inspired by the role of salt tectonics of Lower Fars Series/Gachsaran Formation in hydrocarbon accumulation, the authors considered that the exploration below salt layer should be enforced, and the traps below salt layer in the southern part of the Kuqa foreland basin would be found where salt layer is thicker. On the contrary, the traps should be found both above and below the salt layer in front of the northern mountain where salt layer is thin. The Triassic and Jurassic source rocks are rich in this area with great exploration prospective.

  16. Weathering of rock 'Ginger'

    Science.gov (United States)

    1997-01-01

    One of the more unusual rocks at the site is Ginger, located southeast of the lander. Parts of it have the reddest color of any material in view, whereas its rounded lobes are gray and relatively unweathered. These color differences are brought out in the inset, enhanced at the upper right. In the false color image at the lower right, the shape of the visible-wavelength spectrum (related to the abundance of weathered ferric iron minerals) is indicated by the hue of the rocks. Blue indicates relatively unweathered rocks. Typical soils and drift, which are heavily weathered, are shown in green and flesh tones. The very red color in the creases in the rock surface correspond to a crust of ferric minerals. The origin of the rock is uncertain; the ferric crust may have grown underneath the rock, or it may cement pebbles together into a conglomerate. Ginger will be a target of future super-resolution studies to better constrain its origin.Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator. JPL is an operating division of the California Institute of Technology (Caltech).

  17. Ultrasonic appearance of rhabdomyolysis in patients with crush injury in the Wenchuan earthquake

    Institute of Scientific and Technical Information of China (English)

    SU Bai-hai; QIU Li; FU Ping; LUO Yan; TAO Ye; PENG Yu-lan

    2009-01-01

    Background On May 12,2008,a major earthquake hit Wenchuan County in Sichuan Province of China.The number of cases of crush injury following this event was high.Ultrasonic appearance of rhabdomyolysis (RM) caused by crush injury in the Wenchuan earthquake was observed to evaluate the diagnostic value of ultrasound for detection of rhabdomyolysis.Methods We analyzed clinical and ultrasonic manifestations of 50 cases of RM and 18 cases of RM with osteofascial compartment syndrome (OCS).All cases were caused by crush injury in the Wenchuan earthquake.For these RM patients,we also evaluated the correlations between creatine kinase (CK) and the scope of the muscle lesions as observed by ultrasound.Results There were differences in clinical symptoms,physical signs and ultrasonic appearance between the two groups of patients.The ultrasonic characteristics of the RM were as follows:the striated muscle in the lesions thickened with good overall continuity,and the muscle texture was vague;the strength of the echo was uneven and the echo was cloudy or ground glass-like.Liquid dark zones appeared between muscles and were spindle-like or irregular in shape.There were no blood flow signals in the liquid dark areas.The volume of the striated muscle increased in patients with OCS;the fascia wrapping the muscle showed arched protrusions and significant displacement.The flow velocity of the distal arteries decreased and the spectrum was abnormal.The muscle lesion scope of RM group and RM and OCS group was (7.8±9.0) cm and (13.6±3.1) cm,respectively.The correlation coefficient (r) between the muscle lesion scope and the CK was 0.681 for the RM group (P<0.05) and 0.516 for the RM and OCS group (P <0.05).Conclusions The ultrasonogram of RM has characteristic manifestations and can provide important information for clinical diagnosis and treatment of rhabdomyolysis.

  18. Gases in molten salts

    CERN Document Server

    Tomkins, RPT

    1991-01-01

    This volume contains tabulated collections and critical evaluations of original data for the solubility of gases in molten salts, gathered from chemical literature through to the end of 1989. Within the volume, material is arranged according to the individual gas. The gases include hydrogen halides, inert gases, oxygen, nitrogen, hydrogen, carbon dioxide, water vapor and halogens. The molten salts consist of single salts, binary mixtures and multicomponent systems. Included also, is a special section on the solubility of gases in molten silicate systems, focussing on slags and fluxes.

  19. 圆锥破碎机挤压破碎力建模与衬板磨损预测%Modeling Crushing Pressure and Liner Wear of Cone Crusher

    Institute of Scientific and Technical Information of China (English)

    董钢; 范秀敏; NEUMAYER Johannes

    2011-01-01

    设计并进行了集料挤压破碎力实验,并以此建立较为精确的挤压破碎力求解模型;通过对物料的运动学特征分析和对破碎过程求解,获得破碎腔各区域的压缩比和粒度分布系数及挤压破碎压力;分析了破碎壁表面挤压破碎力的作用形式并求解其分量,实现了对破碎壁表面磨损量的求解.结果表明:所建立的集料挤压破碎力模型的求解结果与实地调研所得结果相符,并实现了对破碎壁表面磨损趋势的预测.%The rock material compression experiments were carried out and a pressure model relating compression ratio and particle size distribution to compression pressure was presented. The kinematics of rock material in crushing chamber was analyzed and a method for calculating the pressure distribution on cone crusher liners was proposed. Calculating the components of crushing pressure and putting them into wear prediction model, the liner wear of cone crusher was achieved. The results show that the model is consistent with the research data, and the prediction of wear is realized.

  20. Resource Assessment of the In-Place and Potentially Recoverable Deep Natural Gas Resource of the Onshore Interior Salt Basins, North Central and Northeastern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini; Donald A. Goddard

    2005-04-15

    The principal research effort for the first six months of Year 2 of the project has been petroleum system characterization. Understanding the burial and thermal maturation histories of the strata in the onshore interior salt basins of the North Central and Northeastern Gulf of Mexico areas is important in petroleum system characterization. The underburden and overburden rocks in these basins and subbasins are a product of their rift-related geohistory. Petroleum source rock analysis and thermal maturation and hydrocarbon expulsion modeling indicate that an effective regional petroleum source rock in the onshore interior salt basins, the North Louisiana Salt Basin, Mississippi Interior Salt Basin, Manila Subbasin and Conecuh Subbasin, was the Upper Jurassic Smackover lime mudstone. The Upper Cretaceous Tuscaloosa shale was an effective local petroleum source rock in the Mississippi Interior Salt Basin and a possible local source bed in the North Louisiana Salt Basin. Hydrocarbon generation and expulsion was initiated in the Early Cretaceous and continued into the Tertiary in the North Louisiana Salt Basin and the Mississippi Interior Salt Basin. Hydrocarbon generation and expulsion was initiated in the Late Cretaceous and continued into the Tertiary in the Manila Subbasin and Conecuh Subbasin. Reservoir rocks include Jurassic, Cretaceous and Tertiary siliciclastic and carbonate strata. Seal rocks include Jurassic, Cretaceous and Tertiary anhydrite and shale beds. Petroleum traps include structural and combination traps.