WorldWideScience

Sample records for acidic crystalline rock

  1. Manifestation of Preferential Flow and Nitrate Transport in Central European Soils on Acid Crystalline Rocks

    Science.gov (United States)

    Dolezal, F.; Cislerova, M.; Vogel, T.; Zavadil, J.; Vacek, J.; Kvitek, T.; Prazak, P.; Nechvatal, M.; Bayer, T.

    2006-12-01

    Large areas of Central Europe are occupied by highlands and peneplains of medium altitudes, built by acid crystalline rocks. The soils overlying them are typically of medium textures. They are neither markedly water- repellent nor greatly swelling and shrinking. These landscapes are characterized by high vulnerability of water bodies, both surface and subsurface. The existing methodologies of vulnerability assessment regard the heavier among these soils as little vulnerable to diffuse pollution, while in reality they may be virtually equally vulnerable, because of the short-circuiting effect of preferential flow and transport. Our experiment site was Valeèov (49° 38' 40" N, 14° 30' 25" E, 461 m a.s.l.) in the Bohemo-Moravian highland, with average annual precipitation 660 mm and average annual air temperature 7.2 ° C. The field trials, starting from 2001, were focused on growing potato under different conditions. Soil moisture content was measured by Theta- probe capacitance sensors, soil water suction by Watermark sensors and tensiometers. Nitrate leaching was monitored by soil solution sampling with ceramic suction cups and zero-tension lysimeters. The hydraulic conductivity of the soil was measured on small cores and by suction and pressure infiltrometers. The following preferential flow manifestations are analyzed and quantified: a) the spatial variability of soil moisture content and suction after rainstorms, b) the spatial and temporal variability of soil's hydraulic conductivity and its dependence on soil moisture content, c) the spatial variability of percolation volumes in parallel lysimeters, d) the variability of nitrate concentrations in the lysimeter leachate, e) the apparent absence of correlation between leachate volumes and leachate concentrations in lysimeters, f) the lower mean and higher variance of leachate concentrations in lysimeters, in comparison with those in suction cups.

  2. Workshop on hydrology of crystalline basement rocks

    Energy Technology Data Exchange (ETDEWEB)

    Davis, S.N. (comp.)

    1981-08-01

    This workshop covered the following subjects: measurements in relatively shallow boreholes; measurement and interpretation of data from deep boreholes; hydrologic properties of crystalline rocks as interpreted by geophysics and field geology; rock mechanics related to hydrology of crystalline rocks; the possible contributions of modeling to the understanding of the hydrology of crystalline rocks; and geochemical interpretations of the hydrology of crystalline rocks. (MHR)

  3. Grouting methodology in crystalline rock

    International Nuclear Information System (INIS)

    For this paper, an initial literature review was conducted to investigate the potential applications of grouting technology for geological disposal of high level radioactive waste (hereafter called geological disposal), and the potential grouting material for each application. The results show the necessity of using suspension grout, such as cement-based grout, during excavation work, especially deep underground. Next, the method to achieve highly effective seals in crystalline rock with cement grout is studied. To enhance the sealing quality, cement grout should penetrate into very fine fractures, e.g. less than 100 μm aperture. In the case of suspension grout, clogging with grout at the openings of rock fractures, especially fine fractures, tends to occur, which results in poor grout penetration. A laboratory experiment was conducted to investigate the clogging phenomenon; the results suggest that high injection pressures could be effective to prevent clogging. Finally, focusing on pre-excavation grouting for horizontal tunnels in crystalline rock, the effective grout hole patterns for achieving high quality sealing was studied. A series of theoretical calculations for water inflow and cost studies were conducted. The results indicate that a dense arrangement of grout holes in a relatively narrow area around a tunnel section, as practised in the Nordic countries, is favorable in hard crystalline rock. (author)

  4. Inelastic deformation in crystalline rocks

    Science.gov (United States)

    Rahmani, H.; Borja, R. I.

    2011-12-01

    The elasto-plastic behavior of crystalline rocks, such as evaporites, igneous rocks, or metamorphic rocks, is highly dependent on the behavior of their individual crystals. Previous studies indicate that crystal plasticity can be one of the dominant micro mechanisms in the plastic deformation of crystal aggregates. Deformation bands and pore collapse are examples of plastic deformation in crystalline rocks. In these cases twinning within the grains illustrate plastic deformation of crystal lattice. Crystal plasticity is governed by the plastic deformation along potential slip systems of crystals. Linear dependency of the crystal slip systems causes singularity in the system of equations solving for the plastic slip of each slip system. As a result, taking the micro-structure properties into account, while studying the overall behavior of crystalline materials, is quite challenging. To model the plastic deformation of single crystals we use the so called `ultimate algorithm' by Borja and Wren (1993) implemented in a 3D finite element framework to solve boundary value problems. The major advantage of this model is that it avoids the singularity problem by solving for the plastic slip explicitly in sub steps over which the stress strain relationship is linear. Comparing the results of the examples to available models such as Von Mises we show the significance of considering the micro-structure of crystals in modeling the overall elasto-plastic deformation of crystal aggregates.

  5. Hydraulic testing in crystalline rock

    International Nuclear Information System (INIS)

    Swedish Geolocical Company (SGAB) conducted and carried out single-hole hydraulic testing in borehole Fi 6 in the Finnsjoen area of central Sweden. The purpose was to make a comprehensive evaluation of different methods applicable in crystalline rocks and to recommend methods for use in current and scheduled investigations in a range of low hydraulic conductivity rocks. A total of eight different methods of testing were compared using the same equipment. This equipment was thoroughly tested as regards the elasticity of the packers and change in volume of the test section. The use of a hydraulically operated down-hole valve enabled all the tests to be conducted. Twelve different 3-m long sections were tested. The hydraulic conductivity calculated ranged from about 5x10-14 m/s to 1x10-6 m/s. The methods used were water injection under constant head and then at a constant rate-of-flow, each of which was followed by a pressure fall-off period. Water loss, pressure pulse, slug and drill stem tests were also performed. Interpretation was carried out using standard transient evaluation methods for flow in porous media. The methods used showed themselves to be best suited to specific conductivity ranges. Among the less time-consuming methods, water loss, slug and drill stem tests usually gave somewhat higher hydraulic conductivity values but still comparable to those obtained using the more time-consuming tests. These latter tests, however, provided supplementary information on hydraulic and physical properties and flow conditions, together with hydraulic conductivity values representing a larger volume of rock. (orig./HP)

  6. Gas migration through crystalline rocks

    International Nuclear Information System (INIS)

    Fractured rocks have been considered as potential host rocks for the deep disposal of radioactive waste in a number of countries. The representative repository concepts involved: a) Low- and intermediate-level waste in water-saturated fractured rock. b) Spent fuel (or HLW) in water-saturated fractured rock. c) Spent fuel in unsaturated fractured tuff (Yucca Mountain). The key gas-related issues are likely to be different for these three repository concepts. Concept (a) typically involves the emplacement of packaged wastes in caverns or tunnels, probably backfilled with a cement grout, and perhaps involving structural concrete lining. The quantities of gas produced for a given volume of waste are expected to be larger than for spent fuel or high-level waste and may include radioactive gases whose release at the surface requires assessment for its potential radiological consequences. For this concept, understanding the mechanisms and effects of gas migration through the geosphere is important in repository performance assessment. For concept (b), the waste is typically contained in long-lasting canisters emplaced in holes lined with compacted bentonite. The bentonite barriers are intended to provide the main barrier to groundwater access to the waste, and the quantities of gas expected to be produced are predicted to be sufficiently small that the host rock is not expected to provide a serious obstacle to gas escape from the region of the canister. In this concept, the main barrier to gas migration is considered to be the bentonite buffer; gas migration through this is discussed in a companion paper. Concept (c) is unique in involving emplacement of wastes in unsaturated rock, well above the water table, in a semi-arid region at Yucca Mountain in Nevada. Here the two-phase flow issues relate primarily to the infiltration of water through the fractured rock from the surface, which may involve flow channelling and intermittent flow, and the generation of strongly heat

  7. Sondierbohrung Boettstein: Hydrogeological testing of crystalline rocks

    International Nuclear Information System (INIS)

    In addition to comprehensive studies in geology, geophysics, hydrochemistry and rock mechanics, a three-phased program for (1) drilling (2) testing and (3) monitoring of the twelve boreholes was proposed. The Boettstein borehole is located in the central part of the target areas. It was the first borehole to be drilled. Drilling in the crystalline granitic basement rocks started at a depth of 315 m below ground surface in November 1982 and was completed in December 1983. The monitoring phase is on-going at this time. The study reported herein describes the hydrogeologic testing of the crystalline rocks and results of the work done by Gartner Lee AG (GLAG) in the Boettstein borehole on behalf of Nationale Genossenschaft Fuer Die Lagerung Radioaktiver Abfaelle (NAGRA). This report describes testing equipment and performance. Also included are sections on the testing and analysis methods that were used to determine the hydrogeologic results. Testing was conducted using single and double packer tools with associated down hole and surface electronic equipment. Down hole information from pressure transducers and thermistors were converted from frequency signals to pressure and temperature readings that were printed, plotted and stored on magnetic tape at the surface facility. All the testing equipment worked well. In summary, the hydrogeologic testing activities at the Boettstein borehole were successful in providing information for NAGRA's regional assessment of the crystalline basement rocks. In addition, water samples could be obtained from discrete intervals for geochemical characterization. Continuing ground water monitoring activities at this borehole will add to the data base provided by this report. (author)

  8. Piedmont_and_Blue_Ridge_crystalline-rock_aquifers

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set represents the extent of the Piedmont and Blue Ridge crystalline-rock aquifers in the states of Alabama, Delaware, District of Columbia, Georgia,...

  9. Petrology of unshocked crystalline rocks and shock effects in lunar rocks and minerals

    Science.gov (United States)

    Chao, E.C.T.; James, O.B.; Minkin, J.A.; Boreman, J.A.; Jackson, E.D.; Raleigh, C.B.

    1970-01-01

    On the basis of rock modes, textures, and mineralogy, unshocked crystalline rocks are classified into a dominant ilmenite-rich suite (subdivided into intersertal, ophitic, and hornfels types) and a subordinate feldspar-rich suite (subdivided into poikilitic and granular types). Weakly to moderately shocked rocks show high strain-rate deformation and solid-state transformation of minerals to glasses; intensely shocked rocks are converted to rock glasses. Data on an unknown calcium-bearing iron metasilicate are presented.

  10. Seismic response to natural gas anomalies in crystalline rocks

    Institute of Scientific and Technical Information of China (English)

    YANG WenCai; JIN ZhenMin; YU ChangQing

    2008-01-01

    According to the geological and seismic reflection data of the Chinese Continental Scientific Drilling (CCSD) main-hole (MH), and the anomalies of CH4, CO2, and He are correlated to the three-component seismic reflectors, especially in horizontal component profiles. However, the seismic response is difficult to be explained as the porosity of crystalline rocks is only about 1% in well section where the gas anomalies occur. Seismic velocity measurement of the MH cores indicated that compared with water-saturated rock samples, seismic velocity (especially the S-wave) could be distinctly decreased by gas contained in tiny cracks despite of the low porosity, and then notable seismic response could be induced in gas-filled crystalline rocks. It could be predicated that if the porosity of certain rocks in the middle crust rose due to water-rock interaction and had natural gas filled, then there would be more probability for natural gas in top of the mid-crust to fill in the crystalline rocks with increased porosity. In such case, based on the decrease of S-wave velocity in crystalline rocks, seismic method could be applied in the future to explore natural gas reservoirs in the middle crust.

  11. Seismic response to natural gas anomalies in crystalline rocks

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    According to the geological and seismic reflection data of the Chinese Continental Scientific Drilling (CCSD) main-hole (MH), and the anomalies of CH4, CO2, and He are correlated to the three-component seismic reflectors, especially in horizontal component profiles. However, the seismic response is dif-ficult to be explained as the porosity of crystalline rocks is only about 1% in well section where the gas anomalies occur. Seismic velocity measurement of the MH cores indicated that compared with wa-ter-saturated rock samples, seismic velocity (especially the S-wave) could be distinctly decreased by gas contained in tiny cracks despite of the low porosity, and then notable seismic response could be induced in gas-filled crystalline rocks. It could be predicated that if the porosity of certain rocks in the middle crust rose due to water-rock interaction and had natural gas filled, then there would be more probability for natural gas in top of the mid-crust to fill in the crystalline rocks with increased porosity. In such case, based on the decrease of Swave velocity in crystalline rocks, seismic method could be applied in the future to explore natural gas reservoirs in the middle crust.

  12. Proceedings of the scientific visit on crystalline rock repository development.

    Energy Technology Data Exchange (ETDEWEB)

    Mariner, Paul E.; Hardin, Ernest L.; Miksova, Jitka [RAWRA, Czech Republic

    2013-02-01

    A scientific visit on Crystalline Rock Repository Development was held in the Czech Republic on September 24-27, 2012. The visit was hosted by the Czech Radioactive Waste Repository Authority (RAWRA), co-hosted by Sandia National Laboratories (SNL), and supported by the International Atomic Energy Agency (IAEA). The purpose of the visit was to promote technical information exchange between participants from countries engaged in the investigation and exploration of crystalline rock for the eventual construction of nuclear waste repositories. The visit was designed especially for participants of countries that have recently commenced (or recommenced) national repository programmes in crystalline host rock formations. Discussion topics included repository programme development, site screening and selection, site characterization, disposal concepts in crystalline host rock, regulatory frameworks, and safety assessment methodology. Interest was surveyed in establishing a %E2%80%9Cclub,%E2%80%9D the mission of which would be to identify and address the various technical challenges that confront the disposal of radioactive waste in crystalline rock environments. The idea of a second scientific visit to be held one year later in another host country received popular support. The visit concluded with a trip to the countryside south of Prague where participants were treated to a tour of the laboratory and underground facilities of the Josef Regional Underground Research Centre.

  13. Radionuclide retardation in crystalline rock fractures

    Energy Technology Data Exchange (ETDEWEB)

    Hoelttae, P.; Hakanen, M.; Siitari-Kauppi, M. [Univ. of Helsinki (Finland). Dept. of Radiochemistry; Hautojaervi, A.

    1995-12-31

    Transport and retardation of slightly sorbing sodium was studied in Syyry area SY-KR7 mica gneiss and in altered porous tonalite. Experiments were performed using dynamic fracture and crushed rock column methods and the static batch method. Flow conditions in the column were determined using tritiated water and chloride as non-sorbing tracers. {sup 14}C-PMMA method was used to study the pore structure of matrices and the surface areas were determined by B.E.T. method. Sodium was retarded strongly in altered tonalite owing to homogeneous porous matrix structure and the composition of alteration minerals. An agreement between retardation values in batch and crushed rock column experiments as well as in fracture column experiments was good.

  14. Stability of bentonite gels in crystalline rock

    International Nuclear Information System (INIS)

    The present, extended study comprises a derivation of a simple rock model as a basis for calculation of the penetration rate of bentonite and of the groundwater flow rate, which is a determinant of the erodibility of the protruding clay film. This model, which is representative of a gross permeability of about 10-8 - 10-9 m/s, implies a spectrum of slot-shaped joints with apertures ranging between 0.1 and 0.5 mm. It is concluded that less than 2percent of the highly compacted bentonite will be lost into traversing joints in 106 years. A closer analysis, in which also Poiseuille retardation and short-term experiments were taken into account, even suggests that the penetration into the considered joints will be less than that. The penetration rate is expected to be 1 decimeter in a few hundred years. The risk of erosion by flowing groundwater was estimated by comparing clay particle bond strength, evaluated from viscometer tests, and theoretically derived drag forces, the conclusion being that the maximum expected water flow rate in the widest joints of the rock model (4 times 10-4 m/s) is not sufficient to disrupt the gel front or the large individual clay flocs that may exist at this front. The experiments support the conclusion that erosion will not be a source of bentonite loss. A worst case scenario with a shear zone being developed across deposition holes is finally considered and in addition to this, the conditions in the fracture-rich tunnel floor at the upper end of the deposition holes are also analysed. This study shows that even if the rock is much more fractured than normal conditions would imply, the bentonite loss is expected to be very moderate and without substantial effect on the barrier functions of the remaining clay cores in the deposition holes. (author)

  15. Some rock mass assessment procedures for discontinuous crystalline rock

    International Nuclear Information System (INIS)

    Underground radioactive waste repositories place especially stringent demands on rock mass assessment and excavation design methodologies. As part of the Building Research Establishment's programme of research into geotechnical site assessment methodology, experiments were undertaken at an underground test site in granite at Troon, Cornwall, and in the Imperial College Laboratories. The results of discontinuity surveys showed that the borehole impression packer probe technique can provide an important source of information for radioactive waste repository site assessment. Similarly, borehole pressure tests can provide valuable data on discontinuity apertures and hydraulic conductivities and on rock mass permeabilities. A versatile, modular borehole pressure test system for use from restricted underground locations was developed and used successfully. Field tests gave values of equivalent parallel plate apertures and discontinuity hydraulic conductivities in similar ranges to those measured in laboratory tests on samples recovered from the site. Discontinuity normal stiffnesses were also measured successfully using the Terra Tek Geothermal Rock Mechanics Test System which proved itself capable of providing laboratory test data required to support geotechnical site assessment procedures for radioactive waste repositories in discontinuous rock. (author)

  16. Mixing induced reactive transport in fractured crystalline rocks

    International Nuclear Information System (INIS)

    In this paper the solute retention properties of crystalline fractured rocks due to mixing-induced geochemical reactions are studied. While fractured media exhibit paths of fast flow and transport and thus short residence times for conservative solutes, at the same time they promote mixing and dilution due to strong heterogeneity, which leads to sharp concentration contrasts. Enhanced mixing and dilution have a double effect that favors crystalline fractured media as a possible host medium for nuclear waste disposal. Firstly, peak radionuclide concentrations are attenuated and, secondly, mixing-induced precipitation reactions are enhanced significantly, which leads to radionuclide immobilization. An integrated framework is presented for the effective modeling of these flow, transport and reaction phenomena, and the interaction between them. In a simple case study, the enhanced dilution and precipitation potential of fractured crystalline rocks are systematically studied and quantified and contrasted it to retention and attenuation in an equivalent homogeneous formation.

  17. Used Fuel Disposal in Crystalline Rocks. FY15 Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yifeng [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-08-20

    The objective of the Crystalline Disposal R&D Work Package is to advance our understanding of long-term disposal of used fuel in crystalline rocks and to develop necessary experimental and computational capabilities to evaluate various disposal concepts in such media. Chapter headings are as follows: Fuel matrix degradation model and its integration with performance assessments, Investigation of thermal effects on the chemical behavior of clays, Investigation of uranium diffusion and retardation in bentonite, Long-term diffusion of U(VI) in bentonite: dependence on density, Sorption and desorption of plutonium by bentonite, Dissolution of plutonium intrinsic colloids in the presence of clay and as a function of temperature, Laboratory investigation of colloid-facilitated transport of cesium by bentonite colloids in a crystalline rock system, Development and demonstration of discrete fracture network model, Fracture continuum model and its comparison with discrete fracture network model.

  18. Interim rock mass properties and conditions for analyses of a repository in crystalline rock

    International Nuclear Information System (INIS)

    A summary of rock properties for generic crystalline rock is compiled from literature sources to provide the input data for analyses of a conceptual repository in crystalline rock. Frequency histograms, mean values and ranges of physical, mechanical, thermal, and thermomechanical properties, and the dependence of these properties on temperature are described. A description of the hydrogeologic properties of a crystalline rock mass and their dependence on depth is provided. In addition, the temperature gradients, mean annual surface temperature, and in situ stress conditions are summarized for the three regions of the United States currently under consideration to host a crystalline repository; i.e., the North Central, Northeastern, and Southeastern. Brief descriptions of the regional geology are also presented. Large-scale underground experiments in crystalline rock at Stripa, Sweden, and in Climax Stock in Nevada, are reviewed to assess whether the rock properties presented in this report are representative of in situ conditions. The suitability of each rock property and the sufficiency of its data base are described. 110 refs., 27 figs., 4 tabs

  19. Crystalline amino acids and nitrogen emission

    NARCIS (Netherlands)

    Verstegen, M.W.A.; Jongbloed, A.W.

    2003-01-01

    Reductions in dietary protein level and supplementation with certain crystalline amino acids is a well-established method of formulating diets to achieve a more ideal amino acid pattern and to reduce nitrogen excretion. Up to 35% reduction in nitrogen excretion may be achieved by supplementing pig d

  20. Sealing of radioactive waste repositories in crystalline rock

    International Nuclear Information System (INIS)

    The natural barrier of the crystalline rock surrounding repositories will be supplemented by engineered barriers and seals in all the repository systems that have been proposed by OECD/NEA member countries. The two buffer materials that are being considered in most countries are Portland cement-based, and bentonite-based materials. The Buffer Mass Test of the OECD/NEA International Stripa Project has demonstrated that highly compacted Na bentonite is well suited as canister embedment and that it effectively seals off boreholes, shafts and tunnels. Bentonite in the form of soft gels that block water flow can be formed in rock by grouting as demonstrated by the current Stripa field work. Cement-based materials, which form nonplastic seals, appear to be useful for certain purposes like rock grouting where very high pressure gradients prevail at the rock construction stage. Longevity is a particularly important matter and current research tends to show that physical and chemical stability will be offered by suitably composed cement and clay-based materials

  1. Disposal of radioactive waste in Swedish crystalline rocks

    Energy Technology Data Exchange (ETDEWEB)

    Greis Dahlberg, Christina; Wikberg, Peter [Svensk Kaernbraenslehantering AB, Stockholm (Sweden)

    2015-07-01

    SKB, Swedish Nuclear Fuel and Waste Management Company is tasked with managing Swedish nuclear and radioactive waste. Crystalline rock is the obvious alternative for deep geological disposal in Sweden. SKB is, since 1988, operating a near surface repository for short-lived low and intermediate-level waste, SFR. The waste in SFR comprises operational and decommissioning waste from nuclear plants, industrial waste, research-related waste and medical waste. Spent nuclear fuel is currently stored in an interim facility while waiting for a license to construct a deep geological repository. The Swedish long-lived low and intermediate-level waste consists mainly of BWR control rods, reactor internals and legacy waste from early research in the Swedish nuclear programs. The current plan is to dispose of this waste in a separate deep geological repository, SFL, sometimes after 2045. Understanding of the rock properties is the basis for the design of the repository concepts. Swedish crystalline rock is mechanical stable and suitable for underground constructions. The Spent Fuel Repository is planned at approximately 500 meters depth in the rock at the Forsmark site. The host rock will keep the spent fuel isolated from human and near-surface environment. The rock will also provide the stable chemical and hydraulic conditions that make it possible to select suitable technical barriers to support the containment provided by the rock. A very long lasting canister is necessary to avoid release and transport of radionuclides through water conducting fractures in the rock. A canister designed for the Swedish rock, consists of a tight, 5 cm thick corrosion barrier of copper and a load-bearing insert of cast iron. To restrict the water flow around the canister and by that prevent fast corrosion, a bentonite buffer will surround the canister. Secondary, the bentonite buffer will retard a potential release by its strong sorption of radionuclides. The SFR repository is situated in

  2. Porosity measurements of crystalline rocks by laboratory and geophysical methods

    International Nuclear Information System (INIS)

    Porosity values of igneous and metamorphic crystalline rocks have been determined from core samples taken at specific depths from Altnabreac, by a combination of laboratory and geophysical techniques. Using resaturation and mercury injection methods in three laboratories within I.G.S., porosity values have been derived and the effect of variations in the measuring techniques and results obtained have been compared. Comparison of inter-laboratory porosity values illustrates that systematic errors are present, resulting in higher porosity values for samples subjected to re-testing. This is considered to be caused by the variable nature of the initial samples combined with the inability to completely dry or resaturate samples during a second testing. Geophysical techniques for determining in situ porosity using the neutron log have been carried out in borehole ALA. The neutron log has been calibrated with laboratory derived porosity values and an empirical formula derived enabling porosity values to be ascribed throughout the logged borehole ALA. Comparison of the porosity results from Altnabreac with crystalline samples elsewhere in America, Europe and the U.K. suggest that porosities at Altnabreac are lower than average. However, very few publications concerned with water movement in crystalline areas actually state the method used. (author)

  3. Search for underground openings for in situ test facilities in crystalline rock

    International Nuclear Information System (INIS)

    With a few exceptions, crystalline rocks in this study were limited to plutonic rocks and medium to high-grade metamorphic rocks. Nearly 1700 underground mines, possibly occurring in crystalline rock, were initially identified. Application of criteria resulted in the identification of 60 potential sites. Within this number, 26 mines and 4 civil works were identified as having potential in that they fulfilled the criteria. Thirty other mines may have similar potential. Most of the mines identified are near the contact between a pluton and older sedimentary, volcanic and metamorphic rocks. However, some mines and the civil works are well within plutonic or metamorphic rock masses. Civil works, notably underground galleries associated with pumped storage hydroelectric facilities, are generally located in tectonically stable regions, in relatively homogeneous crystalline rock bodies. A program is recommended which would identify one or more sites where a concordance exists between geologic setting, company amenability, accessibility and facilities to conduct in situ tests in crystalline rock

  4. Search for underground openings for in situ test facilities in crystalline rock

    Energy Technology Data Exchange (ETDEWEB)

    Wollenberg, H.A.; Strisower, B.; Corrigan, D.J.; Graf, A.N.; O' Brien, M.T.; Pratt, H.; Board, M.; Hustrulid, W.

    1980-01-01

    With a few exceptions, crystalline rocks in this study were limited to plutonic rocks and medium to high-grade metamorphic rocks. Nearly 1700 underground mines, possibly occurring in crystalline rock, were initially identified. Application of criteria resulted in the identification of 60 potential sites. Within this number, 26 mines and 4 civil works were identified as having potential in that they fulfilled the criteria. Thirty other mines may have similar potential. Most of the mines identified are near the contact between a pluton and older sedimentary, volcanic and metamorphic rocks. However, some mines and the civil works are well within plutonic or metamorphic rock masses. Civil works, notably underground galleries associated with pumped storage hydroelectric facilities, are generally located in tectonically stable regions, in relatively homogeneous crystalline rock bodies. A program is recommended which would identify one or more sites where a concordance exists between geologic setting, company amenability, accessibility and facilities to conduct in situ tests in crystalline rock.

  5. Geotechnical assessment and instrumentation needs for isolation of nuclear waste in crystalline rocks: symposium proceedings

    International Nuclear Information System (INIS)

    On October 15-19, 1984, the Geotechnical Assessment and Instrumentation Needs (GAIN) Symposium was convened to examine the status of technology for the isolation of nuclear waste in crystalline rock. The objective of the 1984 GAIN Symposium was to provide technical input to the Crystalline Repository Project concerning: critical issues and information needs associated with development and assessment of a repository in crystalline rock; appropriate techniques and instrumentation for determining the information needed; and technology required to provide the measurement techniques and instrumentation for application in an exploratory shaft in crystalline rock. The findings and recommendations of the symposium are presented in these proceedings

  6. Fractures inside crystalline rocks. Effects of deformations on fluid circulations

    International Nuclear Information System (INIS)

    The modeling of fluid flows inside granite massifs is an important task for the evaluation of the feasibility of radioactive waste storage inside such formations. This document makes a synthesis of the works carried out since about 15 years, in particular by the French bureau of geological and mining research (BRGM), about the hydro-mechanical behaviour of a fracture and about the hydrodynamical characterization of fracture networks inside crystalline rocks: 1 - introduction; 2 - hydro-mechanical behaviour under normal stress: experimental results (hydro-mechanical behaviour, flow regimes, mechanical behaviour, test protocol, complementary tests, influence of samples size), geometrical interpretation of experimental results (relation with walls geometry, relation with voids geometry, relation with contacts geometry), hydro-mechanical modeling (hydraulic modeling, mechanical modeling); 3 - from the hydro-mechanical behaviour under normal stress to the coupling with heat transfers and chemistry: experiment for the study of the chemo-thermo-hydro-mechanical coupling (experimental results, relation with walls morphology), thermo-hydro-mechanical experiments, thermo-hydro-chemical experiments with fractures, conclusions; 4 - hydro-mechanical behaviour during shear: experimental results, geometrical interpretation (relation with the geometry of damaged zones, relation with voids geometry, relation with walls geometry), hydro-mechanical modeling (mechanical modeling, hydro-mechanical modeling of the behaviour during shear). (J.S.)

  7. Performance evaluations related to area characterization of crystalline rock

    International Nuclear Information System (INIS)

    This report discusses the use of performance-based procedures as a planning tool to assist the development and implementation of the Crystalline Rock Repository Project (CRP). Fundamentally, performance assessment is simply a method of expressing our knowledge about a site in a defensible, quantitative manner in terms of meaningful performance criteria. Once developed, these procedures can be utilized as tools to assist the CRP in resolving specific program issues. Conceptually, this involves the ability to estimate site performance based on current information and, by postulating the effect of new information, estimate the changes in performance estimates as a result of future program decisions. This provides a means of examining the probable outcome of alternative program decisions without actually carrying out these decisions. The probable results of different program decision paths can then be compared to determine the optimum choice based on current information. The performance-based procedures rely on the implementation of a general performance assessment system to predict site performance. This system or framework must be at least partially in place in order to implement any of the performance-based procedures. Essentially this would involve identification of program requirements, analysis of processes and characteristics that determine compliance with requirements, development of a procedure to assess site characterization and uncertainties, and development of models to estimate performance. Although the framework needs to be defensible and repeatable, it need not include complex and sophisticated models. Rather, the models and procedures should be consistent with the level of available information at any stage in the program. 65 refs., 54 figs., 12 tabs

  8. Relationship of pegmatites to U-Th mineralization in Precambrian crystalline rocks near Easton, Pennsylvania

    International Nuclear Information System (INIS)

    Previous studies have shown that high radon levels in the Easton area are not simply confined to the igneous crystalline rocks of the Reading Prong. Since the radon is the result of the decay of uranium/thorium bearing minerals, the question then is where are these minerals hosted. Two hypotheses have been proposed for the origin of this mineralization: (1) derivation from an acidic magma during a hydrothermal stage of pegmatite intrusion, or (2) synsedimentary deposition in reducing, oceanic waters with subsequent crystallization of uraninite during metamorphism. The goal of the present study is to determine which process(es) were responsible for the mineralization and to determine where the uranium and thorium are hosted in the Precambrian rocks in the Easton area. Gamma surveys at three locations have demonstrated high radioactivity levels associated with the pegmatites (8,000--750,000 C/min.). Despite the fact that the host rocks and surrounding Paleozoic carbonates have been shown to have high levels of radon, the authors have measured significantly lower radioactivity levels (3,000--8,000 C/min.) in these rocks. The radioactivity levels tend to be high a very short distance into the host and then decrease very rapidly away from the pegmatites. The migmatitic regions in the Byram gneiss (20,000--60,000 C/min.) are considerably higher than the rest of the gneiss (8,000--12,000 C/min.) suggesting remobilization of U-Th during partial melting. These data tend to support the hypothesis that most of the radon is derived from the decay of elements concentrated in the igneous rocks, which subsequently migrated into the host rocks

  9. Effect of polylactic acid crystallinity on its electret properties

    Science.gov (United States)

    Guzhova, A. A.; Galikhanov, M. F.; Kuznetsova, N. V.; Petrov, V. A.; Khairullin, R. Z.

    2016-09-01

    Electret properties of the polylactic acid films with different degree of crystallinity due to different cooling and annealing conditions were studied. Samples with the higher degree of crystallinity showed more stable electret characteristics resulting from amorphous-crystalline interface boundary growth and capturing bigger amount of injected charge carriers by volume energy traps.

  10. Liquid Crystalline Furandicarboxylic Acid-based Aaromatic Polyesters

    NARCIS (Netherlands)

    WILSENS, CAROLUS HENRICUS R. MARIA; RASTOGI, SANJAY; VELD, MARTIJN ARNOLDUS JOHANNES; KLOP, ENNO ANTON; NOORDOVER, BART ADRIANUS JOHANNES

    2013-01-01

    The invention pertains to a fully aromatic liquid crystalline furandicarboxylic acid- based aromatic polyester obtainable from a mixture of monomers comprising 2,5- furandicarboxylic acid, p-hydroxybenzoic acid, an aromatic diol, and 5-40 mol% of an aromatic monocarboxylic acid selected from vanilli

  11. Na, Ca and Sr retardation on crushed crystalline rock

    Energy Technology Data Exchange (ETDEWEB)

    Hoelttae, P.; Siitari-Kauppi, M. [Univ. of Helsinki, Lab. of Radiochemistry (Finland); Lindberg, A. [Geological Survey of Finland (Finland); Hautojaervi, A. [Posiva Oy (Finland)

    1998-12-31

    Different approaches for measuring the interaction between radionuclides and rock matrix are needed to test the compatibility of transport models and retardation experiments. In this work sorption of sodium ({sup 22}Na), calcium ({sup 45}Ca) and strontium ({sup 85}Sr) was studied on mica gneiss, unaltered, moderately altered and strongly altered tonalite samples taken from hole SY-KR7 drilled in the Syyry area in Sievi in western Finland. The mass distribution ratio values for sieved fractions were determined using static batch and thin section methods as well as crushed rock column method. Sodium, calcium and strontium sorption on mica gneiss and unaltered tonalite was slight and no difference due to fraction size was observed. Higher sorption and fair dependence on fraction size was obtained for altered tonalites owing to the composition of alteration minerals and larger specific surface areas. Difference in the R{sub d} values between unaltered and altered rocks is partly the result of the higher specific surface areas for altered rocks. R{sub d}-values calculated from thin section R{sub d}-values and R{sub d}-values obtained from batch experiments were in good greement. Except for sodium, R{sub d}-values obtained from column experiments were lower but in agreement with R{sub d}-values from batch and thin section experiments. (orig.)

  12. Clay-based grout injection in crystalline rock

    International Nuclear Information System (INIS)

    In the sealing of an underground disposal facilities for the high-level radioactive waste, a concept of the clay grouting in the sealing of the underground facilities applied to the hard rock is summarized, based on the results of clay grouting experiments Japan Nuclear Cycle Development Institute (JNC) has performed. JNC performed the clay grouting experiments in-situ of the hard rock. In the experiments, clay grout slurry was injected to the fractures on the floor of the test tunnel and to the excavated damage zone around the key cut off the excavated damage zone along the tunnel. Through the results of these experiments, the injected grout slurry to the target excavated damage zone area improved the hydraulic conductivity of the target area using the injection boreholes opened from the wall of the tunnel. Regarding the adequate design of the clay grouting in the hard rock, information of the fracture characterization (scale and distribution), distribution of the excavated damage zone (hydraulic characteristics), selection of the clay material, injection technique, target area of the injection of the grout (position and region) and so on is required. (author)

  13. Sorption of radionuclides from spent fuel in crystalline rocks

    International Nuclear Information System (INIS)

    The safe disposal of spent nuclear fuel or reprocessed waste is an essential element in the expansion of the nuclear power industry. Stable rock formations e.g. granite are considered to be potential sites for disposal. A major factor in evaluating the degree of safety of the disposal is the sorption of radionuclides in rock, which affects their retardation. The report considers the chemical forms of the hazardous radionuclides of spent nuclear fuel in groundwater and the effects of the water's properties on them. In the groundwater near the Olkiluoto power plant site cesium, strontium and radium are in cationic form, iodine as I-. Technetium would occur as TcO+2, but the pertechnetate form is also possible. Uranium most probably would be as U(VI) plutonium and neptunium as Np(IV) or Np(V). The valences for thorium, americium and curium are not changed in this groundwater and would be +4, +3 and +3, respectively. The actinides in groundwater are all in hydrated or complex form. An increase on the ionic stregth of the groundwater in most instances causes a decrease in the sorption of nuclides since the ion exchange capacity of the rock is limited. Anionic ligands also decrease sorption of cations by complex formation. In some case, on the other hand, high salt concentrations may cause formation of radiocolloids of lanthanides and neptunium and thus increase sorption. In all cases the degree of sorption described by the distribution ratio Ksub(d) was influenced by the pH of the groundwater. Sorption of cesium and strontium increased with growing pH. The sorption behaviour of actinides was in positive correlation with formation of hydroxide complexes at different pH values. The Ksub(d) values of Cs, Sr, Co, Ni and Am for Olkiluoto granites were found to agree with Swedish values, also determined at ambient atmospheric conditions

  14. Fourier transform infrared spectroscopic estimation of crystallinity in SiO2 based rocks

    Indian Academy of Sciences (India)

    Bhaskar J Saikia; G Parthasarathy; N C Sarmah

    2008-10-01

    We present here optical properties and crystallinity index of quartz (SiO2) in natural rocks samples from the Mikir and Khasi hills, Assam, India. Infrared spectroscopy has been used to study the structure of quartz in rock samples and estimate the mining quality of quartz mineral, which is substantiated by calculating the crystallinity index. Systematic investigations of structure have been carried out in between 10 m (1000 cm–1) and 20 m (500 cm–1) bands of silicates. Investigation is based on the assignment of infrared bands to certain structural groups of SiO4 tetrahedra. The crystallinity of samples has been ascertained by comparing the ratio of intensity of the characteristic peak at 778 and 695 cm–1 with the corresponding ratio for a standard sample. The crystallinity parameter is calculated by using a standard procedure which can be used to estimate the distribution of quartz in various rocks for mining purpose. The infrared spectroscopic investigation is found to be an ideal tool for structure elucidation and for estimating quartz crystallinity of the natural samples.

  15. Study on dynamic behavior of a shaft excavation through a faulted crystalline rock mass

    International Nuclear Information System (INIS)

    The 'Mizunami Underground Research Laboratory' has been studying and developing engineering technology for deep underground applications. These applications are multifaceted and are categorized as development of design and construction planning technology, development construction technology, development of countermeasure technology, and development of technology for construction and operation security. In this report, the dynamic behavior of shaft and the surrounding rock mass has been studied with respect to rock mass displacement and stress, the effect of using a concrete liner and excavating through faulted crystalline rock. (author)

  16. Evidentiary requirements to identify potentially acceptable sites (PAS) in crystalline rock

    International Nuclear Information System (INIS)

    This report contains information on the evidentiary requirements to identify potentially acceptable sites in crystalline rock for waste disposal. Topics addressed include: chronology, key regulatory assumptions, statutory framework for identifying potentially acceptable sites, application of 10 disqualifiers, consideration of favorable and potentially adverse conditions, a composite favorability analysis, and a proposed outline for PAS identification decision document

  17. Interpretation of hydraulic testing in crystalline rock at the Leuggern borehole

    International Nuclear Information System (INIS)

    This report presents the results of hydrogeologic interpretations of all analyzable single packer, double packer, and H-log tests conducted in the crystalline rock in the Leuggern borehole. Testing of the Muschelkalk at 74.95 to 117.85 m depth is discussed by Schmassmann (1985). Test 217.9S, which is discussed in this report, contains 14.51 m of Buntsandstein and 4.79 m into the top of the crystalline. A discussion of the testing and interpretation methods is presented. Data analysis was performed using borehole pressure history and thermally-induced pressure effects to be incorporated into the simulations. Formatio pressure (and corresponding equivalent freshwater heads) were determined for 12 test intervals where testing was performed soon after drilling and the formation had an intermediate to high hydraulic conductivity. The calculated equivalent freshwater heads were between 363 m ASL near the top of the crystalline to about 356 m ASL at the bottom of the borehole. Hydraulic conductivities were estimated for 81 intervals, covering the entire crystalline rock portion of the Leuggern borehole. Interpreted hydraulic conductivities ranged from 2.0E-14 to 1.0E-6 ms-1. A base case specific storage of 2.2E-7 m-1 was estimated for the crystalline rock. A sensitivity analysis was conducted for some tests to determine the uncertainty in the best estimate of hydraulic conductivity related to the choice of specific storage. In these cases, specific storage was varied by 1 to 2 orders of magnitude from the base case value. The measured temperature in the borehole ranged from about 19oC at the top of the crystalline rock to about 66oC at the bottom of the borehole. The temperature increases approximately linearly with depth at a gradient of approximately 3.4oC/100 m. (author) 17 figs., 7 tabs., 40 refs

  18. Application of NURE data to the study of crystalline rocks in the Wyoming uranium province

    Energy Technology Data Exchange (ETDEWEB)

    Rush, S.M.; Anderson, J.R.; Bennett, J.E.

    1983-03-01

    The Wyoming uranium province study is a part of the National Uranium Resource Evaluation (NURE) program conducted by Bendix Field Engineering Corporation for the US Department of Energy. The ultimate objective of the entire project is the integration of NURE and other data sources to develop a model for a uranium province centered in Wyoming. This paper presents results of the first phase of the Wyoming uranium province study, which comprises characterization of the crystalline rocks of the study area using NURE hydrogeochemical and stream-sediment data, aerial radiometric and magnetic data, and new data generated for zircons from intrusive rocks in the study area. The results of this study indicate that the stream-sediment, aerial radiometric, aerial magnetic, and zircon data are useful in characterization of the crystalline rocks of the uranium province. The methods used in this project can be applied in two ways toward the recognition of a uranium province: (1) to locate major uranium deposits and occurrences, and (2) to generally identify different crystalline rock types, particularly those that could represent significant uranium source rocks. 14 figures, 8 tables.

  19. Application of NURE data to the study of crystalline rocks in the Wyoming uranium province

    International Nuclear Information System (INIS)

    The Wyoming uranium province study is a part of the National Uranium Resource Evaluation (NURE) program conducted by Bendix Field Engineering Corporation for the US Department of Energy. The ultimate objective of the entire project is the integration of NURE and other data sources to develop a model for a uranium province centered in Wyoming. This paper presents results of the first phase of the Wyoming uranium province study, which comprises characterization of the crystalline rocks of the study area using NURE hydrogeochemical and stream-sediment data, aerial radiometric and magnetic data, and new data generated for zircons from intrusive rocks in the study area. The results of this study indicate that the stream-sediment, aerial radiometric, aerial magnetic, and zircon data are useful in characterization of the crystalline rocks of the uranium province. The methods used in this project can be applied in two ways toward the recognition of a uranium province: (1) to locate major uranium deposits and occurrences, and (2) to generally identify different crystalline rock types, particularly those that could represent significant uranium source rocks. 14 figures, 8 tables

  20. 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.

  1. THE STUDY OF GAS MIGRATION IN CRYSTALLINE ROCK USING INJECTION TESTS

    Directory of Open Access Journals (Sweden)

    Jiří Svoboda

    2012-07-01

    Full Text Available The study of gas migration in crystalline rock using injection tests is being carried out in the frame of the FORGE (Fate of Repository Gases project. The Czech Technical University in Prague (CTU, Centre of Experimental Geotechnics (CEG is participating in WP4 which is focused on disturbed host rock formations with respect to radioactive waste deep repositories. A series of in-situ tests is being conducted at the Josef Underground Laboratory. The aim of the testing is to simulate and study phenomena that might lead to gas-driven radionuclide transport in fractured crystalline rock. The in-situ tests combine migration and large-scale gas injection measurements; gas injection tests are being employed for the study of gas transport. For the purposes of comparison of the behaviour of the rock mass with regard to air and water a series of water pressure tests are also being carried out. The quality of the rock mass is assessed using rock mass classification systems.

  2. Statistical patterns of geochemistry in crystalline rock and effect of sorption kinetics on radionuclide migration

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Shulan; Woerman, A. [Uppsala Univ. (Sweden). Dept. of Earth Sciences

    1998-09-01

    The overall objective of the current project is to develop a quantitative understanding of the effects of spatial variability in physical and geochemical properties of the rock on the migration of radionuclides along a single fracture in crystalline rock. The strategy is first to deduce the basic geostatistics of the main model parameters by means of detailed laboratory (batch) experiments on a large number of rock samples taken from Swedish crystalline basement. The results are then analysed by geostatistical methods and used for stochastic interpretations of a series of laboratory migration experiments to be conducted in a later phase of the project. In an earlier phase of the project, a new mathematical model was developed as a basis for the interpretation of experimental results and the generalisation to performance assessment analyses. The model describes migration of radionuclides along a two-dimensional fracture and includes the transversal diffusion into the rock matrix and surface. To be able to discriminate between the effects of parameter heterogeneity and potential effects of kinetics, a model description has also been developed for first-order sorption kinetics. The main model parameters are represented as spatially random. This report contains results from the batch tests and the geostatistical analysis and the progress of the model formulation for transport of radionuclides. Geostatistics of the main parameters was experimentally determined for two rock types, Aespoe diorite, and Smaaland granite. Drill cores were collected at the Aespoe Hard Rock Laboratory and sawn into a large number of slabs. The porosity, the effective diffusivity and the adsorption characteristics were determined using various experimental methods on the individual pieces. Semi-variograms show that both porosity and effective diffusivity are correlated over a separation distance of 30 to 40 cm. The coefficients of variation of the porosity of rock samples with a size of 20x20

  3. Occurrence of springs in massifs of crystalline rocks, northern Portugal

    Science.gov (United States)

    Pacheco, Fernando António Leal; Alencoão, Ana Maria Pires

    2002-02-01

    An inventory of artesian springs emerging from fractures (fracture springs) was conducted in the Pinhão River Basin and Morais Massif, northern Portugal, comprising an area of approximately 650 km2. Over 1,500 springs were identified and associated with geological domains and fracture sets. Using cross-tabulation analysis, spring distributions by fracture sets were compared among geological environments, and the deviations related to differences in rock structure and, presumably, to differences in deformational histories. The relation between spring frequencies and rock structures was further investigated by spectral determination, the model introduced in this study. Input data are the spring frequencies and fracture lengths in each geological domain, in addition to the angles between fracture strikes and present-day stress-field orientation (θ). The model's output includes the so-called intrinsic densities, a parameter indexing spring occurrence to factors such as fracture type and associated deformational regime and age. The highest densities (12.2 springs/km of lineament) were associated with young shear fractures produced by brittle deformation, and the lowest (0.1) with old tensional and ductile fractures. Spectral determination also relates each orientation class to a dominant structural parameter: where spring occurrence is controlled by θ, the class is parallel to the present-day stress-field orientation; where the control is attributed to the length of fractures, the spring occurrence follows the strike of large-scale normal faults crossing the region. Résumé. Un inventaire des sources artésiennes émergeant de fractures (sources de fractures) a été réalisé dans le bassin de la rivière Pinhão et dans le massif de Morais, dans le nord du Portugal, dans une région couvrant environ 650 km2. Plus de 1,500 sources ont été identifiées et associées à des domaines géologiques et à des ensembles de fractures. Grâce à une analyse de tableaux

  4. Application of rock-cad modelling system in characterization of crystalline bedrock

    Science.gov (United States)

    Saksa, Pauli

    The Finnish power company Teollisuuden Voima Oy studies crystalline bedrock in Finland for final disposal of high-level nuclear fuel waste. In evaluation of the varying lithological and structural conditions CAD-based ROCK-CAD system has been developed. ROCK-CAD is based on true solid modelling approach. One modelled volume consists of several mutually independent submodels. Mainly lithological, structural (fracturing) and hydraulical properties are modelled. ROCK-CAD is in operational use and experiences have been got from four sites modelled this far. The main uses of the software, have been in general visualization, in planning of sopplementary investigations and in qualitative interpretation and model development done by the experts. Computerized models form also the basis for ground water flow simulations and rock mechanical calculations. Two example drawings are presented and discussed.

  5. Guidelines on interim performance constraints for radioactive waste disposal in crystalline rock

    International Nuclear Information System (INIS)

    Interim performance constraints have been developed for preliminary design analyses of a radioactive waste repository in crystalline rock. The approach taken in defining these constraints was to consider the thermal, thermomechanical, and thermochemical beavior for three regions of the repository (very-near field, near field, and far field) during three time periods (operational, containment, and isolation). Physical, thermal, and mechanical limits are proposed. These may be required to support the repository performance objectives defined by the US Nuclear Regulatory Commission in 10 CFR Part 60, Disposal of High-Level Radioactive Wastes in Geologic Repositories, in particular those related to barrier performance after permanent closure (10 CFR 60.113). The performance constraints represent the informed judgment of a Working Group whose members are knowledgeable in matters relating to design of a repository in crystalline rock. The constraints are intended for use in early design studies and will be revised as analytical and experimental information to support revision becomes available

  6. Diffractaic acid: Crystalline structure and physicochemical characterization

    Science.gov (United States)

    de Castro Fonseca, Jéssica; de Oliveira, Yara Santiago; Bezerra, Beatriz P.; Ellena, Javier; Honda, Neli Kika; Silva, Camilla V. N. S.; da Silva Santos, Noemia Pereira; Santos-Magalhães, Nereide Stela; Ayala, Alejandro Pedro

    2016-08-01

    Diffractaic acid (DA) is a secondary metabolite of lichens that belongs to the chemical class of depsides, and some relevant pharmacological properties are associated with this natural product, such as antioxidant, antiulcerogenic and gastroprotective effects. Considering the relevant biological activities and taking into account that the activities are intrinsically related to the structure, the main goal of this study was to elucidate the structure of diffractaic acid by single crystal X-ray diffraction as well to characterize its physicochemical properties by powder X-ray diffraction, thermal analysis and vibrational spectroscopy. It was observed that DA belongs to the monoclinic crystal system, crystallizing in the space group P21/c with the following cell parameters: a = 18.535(7) Å, b = 4.0439(18) Å, c = 23.964(6) Å, β = 91.55(3)°. The crystal packing is characterized by difractaic acid dimers, which are reflected in the vibrational spectrum. These observations were supported by quantum mechanical calculations.

  7. Altered crystalline rock distributed along groundwater conductive fractures and the retardation capacity in the orogenic field of Japan - 16332

    International Nuclear Information System (INIS)

    In the orogenic field Japanese islands, there are wide areas of crystalline rocks that inevitably contain groundwater conductive fractures associated with alteration zones. However, little attention has been given to the formation process and possible influence on the radionuclides migration from radioactive waste repository that might be sited within crystalline rock. In particular, the influences of alteration minerals and micro-fractures, due to chemical sorption and/or physical retardation are required to assess the realistic barrier function. In order to understand the alteration process and the retardation capacity, detailed mineralogical and physico-chemical characterization of altered crystalline rocks have been carried out. Mineralogical analysis reveals that the altered crystalline rocks have been formed through basically two stages of water-rock interaction during and after uplift. Physico-chemical characteristics including laboratory sorption experiments show that altered crystalline rock has a certain volume of accessible porosity, particularly in plagioclase grains, which would influence on nuclide retardation more than the accessible porosity in other minerals present, such as biotite. These results provide confidence that even altered and fractured parts of any crystalline rock that might be encountered in a site for the disposal of high-level radioactive waste may still play a role of barrier function. (authors)

  8. The Studies of A New Type of Crystalline Antimonic Acid

    Institute of Scientific and Technical Information of China (English)

    LIUXiaozhen; ZHOUJiayin; 等

    1993-01-01

    A new type of crystalline antimonic acid Sb2O5·3H2O was synthesized.The composition,crystal structure,the equilibrium distribution coefficients for sodium and potassium ions and the ion-exchange capacity of this exchanger were determined.With this exchanger,sodium inos were removed from potassium chloride,and the content of sodium chloride was reduced from 3.24% to 0.02%.Compared with other ion-exchange materials,the crystalline antimonic acid gives and unusual selectivity for potassium and sodium ions. The different compositions and properties of antimonic acid exchangers are obtained through different preparing conditions and its crystalline formula of Sb2O5·4H2O(C-SbA1) is currently accepted.This paper reports a new type of crystalline antimonic acid-Sb2O5·3H2O(C-SbA2),synthesized by an improved Kuzin′s method.Sodium ions are removed from potassium chloride with C-SbA2.The exchange efficiency is better than that of C-SbA1.

  9. Significance of fracture rim zone heterogeneity for tracer transport in crystalline rock

    Science.gov (United States)

    Cvetkovic, V.

    2010-03-01

    Conducting fractures of crystalline rock are typically altered over long periods of time. The fracture rim zone, a result of these alterations, will as a rule have different physical and chemical properties from the unaltered ("fresh") rock, depending on various microscopic and macroscopic factors of the alterations. In this paper, we study the impact of rim zone heterogeneity, exemplified by a decreasing porosity trend as inferred from the Äspö Hard Rock Laboratory site (Sweden), on short- and long-term tracer transport. Our main finding is that this particular rim zone structure will have a dominant effect on transport of moderately to strongly sorbing tracers on experimental time scales and a notable effect on application time scales. The findings of this work lend further support to the interpretation of the relatively strong retention reported by Cvetkovic et al. The fracture rim zone porosity structure may provide an additional safety margin for sorbing radionuclides in crystalline rock at sites where fracture alteration is prevalent.

  10. Investigation of Davydov splitting in the ir spectra of crystalline dicarboxylic acids

    Directory of Open Access Journals (Sweden)

    T.A. Havrilko

    2009-01-01

    Full Text Available In the present paper the collective (vibrational excitations in molecular crystals were studied. Since the corresponding molecular interactions are characterized by a small radius, the investigation results are important for the molecular and nanoelectronics problem solving.The paper includes the investigation results of resonance (Davydov splitting of the methylene СН2 group rocking vibrations in the IR absorption spectra of even homologues of crystalline dicarboxylic НООС(СН2nСООН acids (crystal space group P21/a. Temperature dependence of the Davydov splitting value for the series of rocking vibration bands of methylene groups in the spectral range 700-1100 cm–1 was investigated for homologues with the number of carbon atoms n = 4-10 using the polarized IR spectroscopy in the wide temperature range 100-300 K. Interpretation of the series of rocking vibration bands of methylene groups in the IR absorption spectra of even homologues of crystalline dicarboxylic acids is performed. Based on the theoretical calculation of normal modes and the assignment of observed absorption bands to vibrations of different symmetry types it was shown, that in the spectra of the studied acids the series of rocking vibration bands may be interpreted as the vibration of (n – 2 methylene groups connected by the collective interaction, in contrast to the case of normal paraffins where all the methylene groups are involved in rocking vibrations. Dependence of the Davydov splitting value on the number of methylene groups is analyzed, and shown that this value increases proportionally to the methylene chain length.

  11. Evaluation of technology for large- and small-diameter boreholes to characterize crystalline rock

    International Nuclear Information System (INIS)

    Testing methods that have been used in large- and small-diameter boreholes (152 and 76 mm [6 and 3 in.]) were evaluated on their ability to characterize crystalline rocks. The methods evaluated included in-hole geomechanical, geophysical, and geohydrologic techniques and associated laboratory core tests; specific emphasis was on techniques that might be used in a field characterization program involving a small number of deep (up to 1500 m [5000 ft]) boreholes. Each technique was evaluated with regard to its effectiveness and limitations, applicability to the acquisition of data for anticipated rock conditions, and adequacy for assessing the required rock/hydrologic characteristics. Many pertinent case histories that helped to assess applicability were reviewed. A principal objective of the evaluations was to assess whether the techniques would be equally useful in both large- and small-diameter boreholes. Of the techniques evaluated, most are suitable for use in both large- and small-diameter boreholes. Borehole logging, hydrologic testing, and core-testing techniques provide suitable results in both borehole diameters. Geomechanical testing techniques provide suitable data in smaller diameter boreholes and have been designed for application at primarily shallow depths. The results of this study will be of use to the Office of Crystalline Repository Development (OCRD) in determining to what degree it is appropriate to use drilling, sampling, and testing techniques in small-diameter boreholes as opposed to large-diameter methods, while at the same time collecting adequate data for characterizing crystalline rock environments for potential use as a high-level radioactive waste repository. Additionally, further developmental work and specific testing techniques are recommended

  12. Time dependency in the mechanical properties of crystalline rocks. A literature survey

    International Nuclear Information System (INIS)

    Because of the long design life, elevated temperatures, and the location at depth (high stresses), time-dependent aspects of the mechanical properties of crystalline rock are potentially important for the design and the long term safety of the radioactive waste repository at Olkiluoto. However, time-dependent effects in rock mechanics are still one of the least understood aspects of the physical behaviour of rock masses, this being partly due to the fact that it is difficult to conduct long-term experimental tests - either in the laboratory or in situ. Yet, the time-dependent mechanical behaviour needs to be characterised so that it can be included in the modelling studies supporting repository design. The Introduction explains the background to the literature survey and includes definitions of the terms 'creep' (increasing strain at constant stress) and 'stress relaxation' (decreasing stress at constant strain). Moreover, it is noted that the rock around an in situ excavation is loaded by the adjacent rock elements and so the timedependent behaviour will depend on the unloading stiffness of these and hence will not actually be either pure creep or pure stress relaxation. The Appendix contains the results of the literature survey of reported time-dependent research as it applies to crystalline rock. A summary of each of the 38 literature items is presented in tabular form covering document number, subject area, document reference, subject matter, objectives, methodology, highlighted figures, conclusions and comments. It is concluded that the time-dependent failure strength of all rocks observed may be interpreted by sub-critical crack growth assisted by the stress corrosion mechanism. Also, certain parameters are known to affect the long-term properties: mineralogy, grain size, water/water chemistry, confining stress and loading history. At some point in the loading history of rock, the state of crack development reaches a point whereby the continued generation of

  13. LIQUID CRYSTALLINE BEHAVIOR OF AROMATIC COPOLYAMIDE IN CONCENTRATED SULPHURIC ACID

    Institute of Scientific and Technical Information of China (English)

    SHAN Guorong; PAN Zhicun; LIU Deshan; ZHOU Qixiang

    1997-01-01

    The liquid crystalline behavior of anisotropic solutions in 100% sulphuric acid of aromatic copolyamide obtained by low-temperature solution copolycondensation of terephthalic acid chloride (TPC), p-phenylene diamine (PPD) and 4, 4'-diamino-diphenylether (DAPE) has been studied by optical microscopy and X-ray diffraction. The effects of inherent viscosity, concentration of copolyamide in sulphuric acid, the content of the third monomer (DAPE) and sequence distribution of copolyamide on the critical concentration,isotropic temperature, phase diagram and texture of liquid crystal were investigated.The schlieren texture was observed and the results of X-ray diffraction indicate that the concentrated solutions of copolyamide exhibit nematic liquid crystalline behavior.

  14. Micromechanical Modeling of Anisotropic Damage-Induced Permeability Variation in Crystalline Rocks

    Science.gov (United States)

    Chen, Yifeng; Hu, Shaohua; Zhou, Chuangbing; Jing, Lanru

    2014-09-01

    This paper presents a study on the initiation and progress of anisotropic damage and its impact on the permeability variation of crystalline rocks of low porosity. This work was based on an existing micromechanical model considering the frictional sliding and dilatancy behaviors of microcracks and the recovery of degraded stiffness when the microcracks are closed. By virtue of an analytical ellipsoidal inclusion solution, lower bound estimates were formulated through a rigorous homogenization procedure for the damage-induced effective permeability of the microcracks-matrix system, and their predictive limitations were discussed with superconducting penny-shaped microcracks, in which the greatest lower bounds were obtained for each homogenization scheme. On this basis, an empirical upper bound estimation model was suggested to account for the influences of anisotropic damage growth, connectivity, frictional sliding, dilatancy, and normal stiffness recovery of closed microcracks, as well as tensile stress-induced microcrack opening on the permeability variation, with a small number of material parameters. The developed model was calibrated and validated by a series of existing laboratory triaxial compression tests with permeability measurements on crystalline rocks, and applied for characterizing the excavation-induced damage zone and permeability variation in the surrounding granitic rock of the TSX tunnel at the Atomic Energy of Canada Limited's (AECL) Underground Research Laboratory (URL) in Canada, with an acceptable agreement between the predicted and measured data.

  15. Study of thermal, mechanical and hydrological coupling for radioactive waste disposal in a crystalline rock formation

    International Nuclear Information System (INIS)

    The purpose of this study is to determine the importance of the hydrothermomechanical coupling in the framework of the safety assessment of HLW geological repositories in crystalline rock. The models describe in parallel, the temperature evolution associated with the power dissipated by the waste, the ensuing thermal stress charges, and their consequences on the fracturing and changes in hydraulic parameters. It describes, as well, effects from buoyancy forces, and the modification of the groundwater flow from these coupled phenomena. This scheme is applied in two dimensions on a generic granitic site. 4 figs

  16. Theoretical and laboratory investigations of flow through fractures in crystalline rock

    International Nuclear Information System (INIS)

    A theoretical model developed for flow through a deformable fracture subject to stresses was successfully tested against laboratory experiments. The model contains no arbitrary parameters and can be used to predict flow rates through a single fracture if the fractional fracture contact area can be estimated and if stress-deformation data are available. These data can be obtained from laboratory or in situ tests. The model has considerable potential for practical application. The permeability of ultralarge samples of fractured crystalline rock as a function of stresses was measured. Results from tests on a pervasively fractured 1-m-diameter specimen of granitic rock showed that drastically simplifying assumptions must be used to apply theoretical models to this type of rock mass. Simple models successfully reproduce the trend of reduced permeability as stress is applied in a direction normal to the fracture plane. The tests also demonstrated how fracture conductivity increases as a result of dilatancy associated with shear displacements. The effect of specimen size on the hydraulic properties of fractured rock was also investigated. Permeability tests were performed on specimens of charcoal black granite containing a single fracture subjected to normal stress. Results are presented for tests performed on a 0.914-m-diameter specimen and on the same specimen after it had been reduced to 0.764 m in diameter. The data show that fracture conductivity is sensitive to stress history and sample disturbance

  17. GEOTECHNICAL ASSESSMENT AND INSTRUMENTATION NEEDS FOR NUCLEAR WASTE ISOLATION IN CRYSTALLINE AND ARGILLACEOUS ROCKS SYMPOSIUM

    Energy Technology Data Exchange (ETDEWEB)

    Authors, Various

    1978-12-19

    Today there exists in the United States a large volume of nuclear wastes that result from both military and commercial activities. The United States has to date placed major emphasis on disposal in only one rock type--salt--whereas other nations have considered other rock types, such as granite in England and Sweden and clays in Belgium. No comprehensive evaluation of isolation in rocks other than salt has been made in the United States, and it is most appropriate that other rock types be evaluated both for constructing disposal sites in areas devoid of salt and also for having alternative waste management plans in case substantial problems are encountered in using salt as a disposal medium. To evaluate the state-of-the-art, research needs, and research priorities related to waste disposal in largely-impermeable rocks, scientists and engineers working on geologic aspects of nuclear waste disposal were brought together. The Geotechnical Assessment and Instrumentation Needs (GAIN) Symposium for Nuclear Waste Isolation in Crystalline and Argillaceous Rocks was held July 16-20, 1978 in Berkeley. This report and recommendations are the proceedings from that symposium. The location, design, and testing of a potential nuclear waste disposal site are both a geologic and an engineering problem. Disposal requires isolating the wastes from the surface and subsurface of the earth for a period of time of ten to hundreds of thousands of years. Engineers have never before been called upon to predict the behavior of structures or the flow of groundwater so far into the future.

  18. The effect of rock composition on cyanobacterial weathering of crystalline basalt and rhyolite.

    Science.gov (United States)

    Olsson-Francis, K; Simpson, A E; Wolff-Boenisch, D; Cockell, C S

    2012-09-01

    The weathering of volcanic rocks contributes significantly to the global silicate weathering budget, effecting carbon dioxide drawdown and long-term climate control. The rate of chemical weathering is influenced by the composition of the rock. Rock-dwelling micro-organisms are known to play a role in changing the rate of weathering reactions; however, the influence of rock composition on bio-weathering is unknown. Cyanobacteria are known to be a ubiquitous surface taxon in volcanic rocks. In this study, we used a selection of fast and slow growing cyanobacterial species to compare microbial-mediated weathering of bulk crystalline rocks of basaltic and rhyolitic composition, under batch conditions. Cyanobacterial growth caused an increase in the pH of the medium and an acceleration of rock dissolution compared to the abiotic controls. For example, Anabaena cylindrica increased the linear release rate (R(i)(l)) of Ca, Mg, Si and K from the basalt by more than fivefold (5.21-12.48) and increased the pH of the medium by 1.9 units. Although A. cylindrica enhanced rhyolite weathering, the increase in R(i)(l) was less than threefold (2.04-2.97) and the pH increase was only 0.83 units. The R(i)(l) values obtained with A. cylindrica were at least ninefold greater with the basalt than the rhyolite, whereas in the abiotic controls, the difference was less than fivefold. Factors accounting for the slower rate of rhyolite weathering and lower biomass achieved are likely to include the higher content of quartz, which has a low rate of weathering and lower concentrations of bio-essential elements, such as, Ca, Fe and Mg, which are known to be important in controlling cyanobacterial growth. We show that at conditions where weathering is favoured, biota can enhance the difference between low and high Si-rock weathering. Our data show that cyanobacteria can play a significant role in enhancing rock weathering and likely have done since they evolved on the early Earth.

  19. The origin, source and cycling of methane in deep crystalline rock biosphere

    Directory of Open Access Journals (Sweden)

    Riikka eKietäväinen

    2015-07-01

    Full Text Available The emerging interest in using stable bedrock formations for industrial purposes, e.g. nuclear waste disposal, has increased the need for understanding microbiological and geochemical processes in deep crystalline rock environments, including the carbon cycle. Considering the origin and evolution of life on Earth, these environments may also serve as windows to the past. Various geological, chemical and biological processes can influence the deep carbon cycle. Conditions of CH4 formation, available substrates and time scales can be drastically different from surface environments. This paper reviews the origin, source and cycling of methane in deep terrestrial crystalline bedrock with an emphasis on microbiology. In addition to potential formation pathways of CH4, microbial consumption of CH4 is also discussed. Recent studies on the origin of CH4 in continental bedrock environments have shown that the traditional separation of biotic and abiotic CH4 by the isotopic composition can be misleading in substrate-limited environments, such as the deep crystalline bedrock. Despite of similarities between Precambrian continental sites in Fennoscandia, South Africa and North America, where deep methane cycling has been studied, common physicochemical properties which could explain the variation in the amount of CH4 and presence or absence of CH4 cycling microbes were not found. However, based on their preferred carbon metabolism, methanogenic microbes appeared to have similar spatial distribution among the different sites.

  20. The origin, source, and cycling of methane in deep crystalline rock biosphere

    Science.gov (United States)

    Kietäväinen, Riikka; Purkamo, Lotta

    2015-01-01

    The emerging interest in using stable bedrock formations for industrial purposes, e.g., nuclear waste disposal, has increased the need for understanding microbiological and geochemical processes in deep crystalline rock environments, including the carbon cycle. Considering the origin and evolution of life on Earth, these environments may also serve as windows to the past. Various geological, chemical, and biological processes can influence the deep carbon cycle. Conditions of CH4 formation, available substrates and time scales can be drastically different from surface environments. This paper reviews the origin, source, and cycling of methane in deep terrestrial crystalline bedrock with an emphasis on microbiology. In addition to potential formation pathways of CH4, microbial consumption of CH4 is also discussed. Recent studies on the origin of CH4 in continental bedrock environments have shown that the traditional separation of biotic and abiotic CH4 by the isotopic composition can be misleading in substrate-limited environments, such as the deep crystalline bedrock. Despite of similarities between Precambrian continental sites in Fennoscandia, South Africa and North America, where deep methane cycling has been studied, common physicochemical properties which could explain the variation in the amount of CH4 and presence or absence of CH4 cycling microbes were not found. However, based on their preferred carbon metabolism, methanogenic microbes appeared to have similar spatial distribution among the different sites. PMID:26236303

  1. Hydraulic properties and modelling of potential repository sites in Swedish crystalline rock

    International Nuclear Information System (INIS)

    Hydraulic properties of crystalline rock from four potential sites in Sweden have been measured and analyzed. The hydraulic conductivity of the bedrock has been established by transient water-injection tests with constant head followed by a pressure fall-off period. When evaluating the hydraulic conductivity, the continuum approach has been utilized. From the transient tests, the piezometric head in each section has also been calculated. Based on geological, geophysical and hydrogeological data, the sites have been divided into different hydraulic units comprising regional fracture zones, local fracture zones and rock mass. The calculated effective hydraulic conductivity based on the geometric mean values has been found to decrease with depth in all different hydraulic units. According to the Swedish concept a repository will be sited in the rock mass at 500 m depth. On repository depth, the effective hydraulic conductivity is about 5.10-11 m/s. Model calculations have been performed utilizing a numerical 3-dimensional FEM-model. The size of the modelled areas is 2-5 km2. The influence of the fracture zones on the groundwater flow at repository depth has been illustrated by alternative modelling

  2. Geological assessment of crystalline rock formations with a view to radioactive waste disposal

    International Nuclear Information System (INIS)

    Field work has been concentrated at the Altnabreac Research Site on north-east Scotland, where three deep boreholes to approximately 300 m and 24 shallow boreholes to approximately 40 m were drilled. The movement of groundwater within 300 m of the surface was investigated using a specially developed straddle packer system. Geochemical studies have demonstrated that most groundwater is dominated by recent recharge but one borehole yielded water with an age of around 104 years. Geophysical borehole logging has shown that the full wave train sonic logs and the acoustic logs show most promise for the assessment of crystalline rocks. In the laboratory the interaction of rocks and groundwater at the temperature/pressure conditions to be expected in a repository has established the geochemical environment to which waste canisters and backfill materials would be subjected. Other generic studies reported include the characterization of geotechnical properties of rocks at elevated temperatures and pressures, the development of a new cross-hole sinusoidal pressure test for the measurement of hydraulic properties and the use of thermal infra-red imagery to detect groundwater discharge zones

  3. Technical approach to resolving issues on rock mechanics as applied to development of a nuclear waste repository in a crystalline rock formation

    International Nuclear Information System (INIS)

    This paper summarizes the technical efforts for resolving issues on rock mechanics as applied to development of a nuclear waste repository in a crystalline rock formation. This section provides background information and definitions pertinent to rock mechanics. Section 2.0 presents the rock mechanics issues related to licensing, design, and construction of a waste repository. Section 3.0 presents the technical approach to the resolution of issues and concludes that a multi-faceted approach involving principally site characterization, laboratory testing, numerical modeling and analysis, and in situ testing and monitoring is required. While this technical approach is directed to further scientific understanding and quantification of the phenomena involved accompanying the thermal heating of rock from nuclear waste, it is emphasized that formulation of a design basis for an engineered rock structure will precede the development of a large waste repository. Section 4.0 summarizes the status of resolution activities in the areas of thermomechanical effects, coupled thermal, mechanical, and hydrological phenomena, mine-induced fracturing, mine stability, and seismicity. Section 5.0 gives a concluding statement. Under the present project plans, technical activities are proceeding on multiple fronts involving field, laboratory, and numerical modeling and analysis studies of the important phenomena related to the disposal of radioactive waste in crystalline rock. The advancement of the state of the art in rock mechanics from these activities will culminate in the risk analysis and the formulation of a design basis for repositories

  4. Seismic velocities, anisotropy and elastic properties of crystalline rocks and implications for interpretation of seismic data

    Science.gov (United States)

    Sun, Shengsi

    The knowledge of seismic and elastic properties of polyphase crystalline rocks under high pressure and temperature conditions is fundamental in interpreting in-situ seismic data (e.g., reflections, refractions, received functions, and tomography). These data may be understood in terms of lithology, mineralogy, and physical state and as such they allow establishing lithospheric structure and composition models of continents. The present study aims to better understand how the seismic and elastic properties [e.g., compressional- and shear-wave velocities (Vp and Vs), anisotropy, and elastic parameters] under confining pressure are affected by modal and chemical compositions, microstructures, lattice preferred orientations (LPO) of rocks and by the geometry and state of microcracks. This thesis consists of six chapters. Chapter 1 addresses the framework of rock seismic property studies, focusing on the concepts of elasticity and mixture rules, and providing an overview on results of statistical analysis on previous laboratory-measured seismic data of different lithologies and rock-forming minerals, and on the seismic anisotropy of the continental crust and upper mantle. Chapter 2 deals with seismic and elastic properties measured at hydrostatic pressures up to 800 MPa for 12 representative samples from the Longmen Shan complex in which the great 2008 Wenchuan earthquake took place. These allowed understanding how coseismic ruptures nucleated and propagated. This study also offers necessary information for broadband simulations of strong ground motions in the assessment and forecast of earthquake hazards in the region. Furthermore, the study, which yields a moment magnitude of 7.9-8.0 given the variation in the dip of the coseismic ruptures and the uncertainty in the depth to which the coseismic rupture may propagate downwards below the depth of the mainshock hypocenter, presents the first accurate quantification of the 2008 Wenchuan earthquake’s size. Chapter 3 is

  5. VSP in crystalline rocks - from downhole velocity profiling to 3-D fracture mapping

    International Nuclear Information System (INIS)

    VSP surveys have been carried out at several potential nuclear waste disposal sites in Finland since the mid 80s. To date, more than 200 three-component profiles have been measured. The main purpose of the surveys was to detect fracture zones in the crystalline bedrock and to determine their position. Most seismic events could be linked to zones of increased fracturing observed in the borehole logs. The more pronounced seismic reflectors could be correlated with hydrogeologically significant zones, which have been the main targets in the investigations. Processing and interpretation methods have been developed specifically for VSP surveys in crystalline rocks: Weak reflections from thin fracture zones are enhanced by multi-channel filtering techniques based on the Radon transform. The position and orientation of the fracture zones are determined by polarisation analysis and by combining data from several shot points. The compilation of the results from several boreholes gives a comprehensive image of the fracture zones at the scale of the whole site. The discussion of the methodology is based on examples from the Olkiluoto site, in SW Finland

  6. Radiation induced crystallinity damage in poly(L-lactic acid)

    CERN Document Server

    Kantoglu, O

    2002-01-01

    The radiation-induced crystallinity damage in poly(L-lactic acid) (PLLA) in the presence of air and in vacuum, is studied. From the heat of fusion enthalpy values of gamma irradiated samples, some changes on the thermal properties were determined. To identify these changes, first the glass transition temperature (T sub g) of L-lactic acid polymers irradiated to various doses in air and vacuum have been investigated and it is found that it is independent of irradiation atmosphere and dose. The fraction of damaged units of PLLA per unit of absorbed energy has been measured. For this purpose, SAXS and differential scanning calorimetry methods were used, and the radiation yield of number of damaged units (G(-u)) is found to be 0.74 and 0.58 for PLLA samples irradiated in vacuum and air, respectively.

  7. An overview of potential isotopic techniques for dating groundwaters in crystalline rocks

    International Nuclear Information System (INIS)

    The rate of groundwater flow through a particular rock formation is a major factor in determining whether it may be an acceptable geologic medium for the disposal of high-level nuclear fuel waste. This report reviews isotopic techniques that could be potentially useful for the dating of groundwaters in crystalline rocks of the Canadian Precambrian Shield and presents and discusses results that have been reported in the literature. Carbon-14 dating is the most widely used technique for dating groundwaters up to about 50,000 years old, but the method requires that the measured carbon-14 activity be corrected for subsurface contributions of 'dead' carbon to the dissolved inorganic carbon. Thus, the geochemical evolution of the groundwater flow system must be well understood. Moreover, there are practical limitations on applying this technique to deep, saline groundwaters because of their very low alkalinity concentrations. Nevertheless, existing isotopic data suggest that groundwaters at depths of 500 m or greater are generally at least 10,000 years old. Refinement of the krypton-81 technique offers the most promise in the future for being able to date deep saline groundwaters and brines that are present at depths of 1000 m or greater. (author) 92 refs., 1 tab., 3 figs

  8. Impact of climate on groundwater recharge in the crystalline basement rocks aquifer of Northern Ghana

    Science.gov (United States)

    Koffi, K. V.

    2015-12-01

    Water is the cornerstone of human life and for all economic developments. West Africa and specifically Ghana are no exception to this reality.Northern Ghana is characterized by a semi-arid climate, with prolonged dry season (7 months of very few rainfall) leading to the drying up of many rivers and streams. In addition, rainfall is highly variable in space and time. Therefore, surface water is unreliable and insufficient to meet the water demands for socio-economic development in this area. As a result, the area is heavily dependent on groundwater for domestic water supply as well as for dry season irrigation of vegetables (cash crops).However, aquifers in northern Ghana are dominantly the hard rock type (Crystalline basement rock). This aquifer has no primary porosity and may not be able to sustain the increasing demand on the resource. Further, climate change may worsen the situation as recharge is dependent on rainfall in northern Ghana. Therefore, it is important to understand exactly how climate change will impact on recharge to the groundwater for sustainable development and management of the resource.Previous groundwater studies in Northern Ghana barely analyzed the combined impacts of Climate change on the recharge to the groundwater. This research is aimed at determining the current relationship between groundwater recharge and rainfall and to use the relationships to determine the impacts of changes in climate on the groundwater recharge. The results will inform plans and strategies for sustainably managing groundwater resources in Ghana and the Volta basin.

  9. The Crystalline Changes of Starch from Rhizoma Dioscorea by Acid Hydrolysis

    Institute of Scientific and Technical Information of China (English)

    Shu Jun WANG; Wen Yuan GAO; Jing Lin YU; Pei Gen XIAO

    2006-01-01

    The changes in crystalline properties of starch from Rhizoma Dioscorea by acid hydrolysis was characterized by X-Ray diffractometry (XRD). The results revealed that the crystalline type of Rhizoma Dioscorea starch changed from C-type to A-type after 16 days of the acid hydrolysis. This phenomenon was different from that of other starches subjected to the acid hydrolysis. The results revealed that the B-polymorphs of C-type starch constituted the amorphous regions while the crystalline areas were mainly composed of A-polymorphs. The degree of crystallinity of the acid-thinned starch increased gradually with the time of acid hydrolysis.

  10. Dielectric Relaxation Phenomena of Polylactic Acid with -Crystalline Chitin

    Directory of Open Access Journals (Sweden)

    Katsuyoshi Shinyama

    2012-01-01

    Full Text Available -crystalline chitin was added to polylactic acid (PLA, and this PLA was then heat-treated at 100∘C for one minute. The crystallinity of the heat-treated PLA increased to more than 40%, and its crystallization speed also increased significantly. The temperature dependency of these materials’ relative permittivity ( and relative dielectric loss factor ( was also examined. The dielectric absorption peak value in  curve of the PLA to which chitin was added and was smaller than that of PLA without chitin. Additionally, the Havriliak-Negami relaxation function was used to produce approximation curves for the frequency dependency of  and  of chitin with PLA added at 80∘C. As a result, the relaxation strength (Δ of the chitin with PLA added was smaller than that of the PLA without chitin, and the relaxation time ( of the chitin with PLA added was approximately 2.5 times larger than that of the PLA without chitin.

  11. Immobilization of uranium and neptunium by microorganisms in subsurface crystalline rock environments

    International Nuclear Information System (INIS)

    In crystalline rock, the dominant transport medium for radionuclides is groundwater flowing through subsurface fractures. Since groundwater is containing microorganisms, fracture surfaces support biological growth of microbial communities, the so-called bio-films. The microbial diversity of these bio-films depends on the microbial consortia and the chemical composition of the fracture water. Subsurface bio-films have a significant effect on the adsorption capacity of host rock formations by forming a barrier between the rock surface and the groundwater. They can significantly affect subsurface biogeochemical interactions, leading to the immobilization and adsorption of radionuclides. Microbial studies were performed to evaluate the relevance of microbial processes for the immobilization of radionuclides in a deep crystalline repository for high-level radioactive waste. Studies were performed in Olkiluoto, in the rock characterization facility ONKALO in Finland, and in the Aespoe Hard Rock Laboratory (HRL) in Sweden. Massive 5-10-mm thick bio-films were observed in both sites attached to tunnel walls where groundwater was seeping from bedrock fractures. In experiments the effect of uranium on bio-films was studied on site in the ONKALO tunnel by adding UO2(ClO4)2 with a final U-concentration of 1.0x10-5 M to the fracture water in a self-constructed flow cell by using detached bio-film samples. bio-film specimens collected for transmission electron microscopy studies indicated that uranium in the bio-film was immobilized intracellularly in microorganisms as needle-shaped uranyl phosphate minerals, similar to meta-Autunite (Ca[UO2]2[PO4]2.10-12H2O). In contrast, thermodynamic calculation of the theoretical predominant fields of uranium species and time-resolved laser fluorescence spectroscopy showed that the formation of aqueous uranium carbonate species Ca2UO2(CO3)3 and Mg2UO2(CO3)3 was predicted due to the high concentration of carbonate in the groundwater. At the

  12. Enhancing the crystalline degree of carbon nanotubes by acid treatment, air oxidization and heat treatment

    Institute of Scientific and Technical Information of China (English)

    Chensha Li; Baoyou Zhang; Xingjuan Chen; Xiaoqing Hu; Ji Liang

    2005-01-01

    Three approaches of treating carbon nanotubes (CNTs) including acid treatment, air oxidization and heat treatment at high temperature were studied to enhance the crystalline degree of carbon nanotubes. High temperature heat-treatment elevates the crystalline degree of carbon nanotubes. Acid treatment removes parts of amorphous carbonaceous matter through its oxidization effect.Air oxidization disperses carbon nanotubes and amorphous carbonaceous matter. The treatment of combining acid treatment with heat-treatment further elevates the crystalline degree of carbon nanotubes comparing with acid treatment or heat-treatment. The combination of the three treatments creates the thorough effects of enhancing the crystalline degree of carbon nanotubes.

  13. Acid rock drainage and climate change

    Science.gov (United States)

    Nordstrom, D.K.

    2009-01-01

    Rainfall events cause both increases and decreases in acid and metals concentrations and their loadings from mine wastes, and unmined mineralized areas, into receiving streams based on data from 3 mines sites in the United States and other sites outside the US. Gradual increases in concentrations occur during long dry spells and sudden large increases are observed during the rising limb of the discharge following dry spells (first flush). By the time the discharge peak has occurred, concentrations are usually decreased, often to levels below those of pre-storm conditions and then they slowly rise again during the next dry spell. These dynamic changes in concentrations and loadings are related to the dissolution of soluble salts and the flushing out of waters that were concentrated by evaporation. The underlying processes, pyrite oxidation and host rock dissolution, do not end until the pyrite is fully weathered, which can take hundreds to thousands of years. These observations can be generalized to predict future conditions caused by droughts related to El Ni??o and climate change associated with global warming. Already, the time period for dry summers is lengthening in the western US and rainstorms are further apart and more intense when they happen. Consequently, flushing of inactive or active mine sites and mineralized but unmined sites will cause larger sudden increases in concentrations that will be an ever increasing danger to aquatic life with climate change. Higher average concentrations will be observed during longer low-flow periods. Remediation efforts will have to increase the capacity of engineered designs to deal with more extreme conditions, not average conditions of previous years.

  14. Characterization of crystalline rocks in deep boreholes. The Kola, Krivoy Rog and Tyrnauz boreholes

    International Nuclear Information System (INIS)

    SKB studies, as one alternative, the feasibility of disposing of spent nuclear fuel in very deep boreholes. As a part of this work NEDRA has compiled geoscientific data from three superdeep boreholes within the former Soviet Union. The holes considered were: the Kola borehole, 12261 m deep and located on the Kola Peninsula, the Krivoy Rog borehole, 5000 m deep and located in Ukraine, and the Tyrnauz borehole, 4001 m deep and located between the Black Sea and the Caspian Sea. These boreholes all penetrate crystalline formations, but major differences are found when their tectonic environments are compared. Excluding the uppermost horizon affected by surface phenomena, data do not indicate any general correlation between depth and the state of rock fracturing, which is instead governed by site specific, lithological and tectonical factors. This applies also to fracture zones, which are found at similar frequencies at all depths. As opposed to the structural data, the hydrogeological and hydrochemical information reveals a vertical zonation, with clear similarities between the three boreholes. An upper zone with active circulation and fresh or slightly mineralized groundwaters reaches down 1000-2000 m. The interval from 1000-2000 m down to 4000-5000 m can be characterized as a transition zone with lower circulation rates and gradually increasing mineralisation. Below 4000-5000 m, strongly mineralized, stagnant, juvenile or metamorphogenic waters are found. Geothermal data verify the existence of this zonation. 28 figs, 30 tabs

  15. Typical repository conditions for generic commercial and defense high-level nuclear waste and spent fuel repositories in crystalline rock

    International Nuclear Information System (INIS)

    This report summarizes activities to determine conditions for temperature, pressure, fluid, chemical, and radiation environments typical of those that may be expected to exist in commercial and defense high-level nuclear waste and spent fuel repositories in crystalline rock. In the DOE Crystalline Repository Project, the term crystalline rocks are defined as intrusive igneous and high-rank metamorphic rocks rich in silicate minerals with a grain size sufficiently coarse that individual materials can be distinguished with the unaided eye. These conditions were generated by the Reference Repository Conditions Interface Working Group (RRC-IWG), an ad hoc IWG established by the National Terminal Storage (NWTS) Program's Isolation Interface Control Board. The repository conditions are based on the standard room-and-pillar mined repository concept with waste emplaced in vertical holes drilled in the room floor. Some important results obtained are given below for the selected local areal thermal loadings of 20, 25, and 13.5 W/m2 for spent fuel (SF), commercial high-level waste (CHLW), and defense high-level waste (DHLW), respectively. In all cases, the results below are given in order for SF, CHLW, and DHLW. Some thermal results are: maximum waste temperature - 190, 225, and 1200C; maximum rock temperature - 150, 165, and 1050C. The length of time for significant thermal exposure is greater for SF than the other wastes. Vapor phase pressures are not expected to rise significantly above atmospheric until the repository is sealed. After sealing, the water pressure inside the sealed excavations will gradually increase to the local hydrostatic head. A generic crystalline rock ground-water composition and expected gamma radiation dose rates are also provided in the report. 11 references, 10 figures, 6 tables

  16. Assessment of site-scale hydrogeological modelling possibilities in crystalline hard rock for safety appraisal

    Energy Technology Data Exchange (ETDEWEB)

    Geier, J. [Cleanwater Hardrock Consulting, Corvallis, OR (United States); Luukkonen, A.

    2012-09-15

    This review describes the state-of-the-art in hydrogeological modelling for safety-case studies related to spent-fuel repositories in crystalline hard rock, focusing on issues of relevance for the KBS-3 disposal concept in Nordic environments. The review includes a survey of model capabilities and assumptions regarding groundwater flow processes, geological and excavation-related features, and boundary conditions for temperate, periglacial, and glacial climates. Modelling approaches are compared for research sites including the Stripa mine (Sweden), the Grimsel Test Site (Switzerland), the Whiteshell Underground Research Laboratory (Canada), the Aspo Hard Rock Laboratory and Simpevarp-Laxemar site (Sweden), the Forsmark site (Sweden), the Waste Isolation Pilot Plant site (USA), and Olkiluoto (Finland). Current hydrogeological models allow realistic representations, but are limited by availability of data to constrain their properties. Examples of calibrations of stochastic representations of heterogeneity are still scarce. Integrated models that couple flow and non-reactive transport are now well established, particularly those based on continuum representations. Models that include reactive transport are still mainly in the realm of research tools. Thus far, no single software tool allows fully coupled treatment of all relevant thermal, hydraulic, mechanical, and chemical transport processes in the bedrock, together with climate-related physical processes at the ground surface, and with explicit treatment of bedrock heterogeneity. Hence practical applications require combinations of models based on different simplifications. Key improvements can be expected in treatment of the unsaturated zone, simulation of heterogeneous infiltration at the surface, and hydromechanical coupling. Significant advances have already been made in the amounts and types of data that can be used in site-scale models, including large datasets to define topography and other surface

  17. Identification of transport processes in Southern Indian fractured crystalline rock using forced-gradient tracer experiments

    Science.gov (United States)

    Guihéneuf, Nicolas; Bour, Olivier; Boisson, Alexandre; Le Borgne, Tanguy; Becker, Matthew R.; Nigon, Benoit; Wajiduddin, Mohammed; Ahmed, Shakeel; Maréchal, Jean-Christophe

    2015-04-01

    Understanding dominant transport processes is essential to improve prediction of contaminants transfer in fractured crystalline rocks. In such fractured media, solute transport is characterized by fast advection within open and connected fractures and sometimes by matrix diffusion that may be enhanced by chemical weathering. To investigate this phenomenon, we carried out radially convergent and push-pull tracer experiments in the fractured granite of the Experimental Hydrogeological Park of Choutuppal (Southern India). Tracer tests were performed in the same permeable fracture from few meters to several ten meters and from few hours to two weeks to check the consistency of the results at different spatial and temporal scales. These different types of forced gradient tracer experiments allow separation of the effects of advection and diffusion on transport. Breakthrough curves from radially convergent tracer tests display systematically a -2 power law slope on the late time behavior. This tailing can be adequately represented by a transport model that only takes into account heterogeneous advection caused by fluid flow channeling. The negligible impact of matrix diffusion was confirmed by the push-pull tracer tests, at least for the duration of experiments. A push-pull experiment carried out with a cocktail of two conservative tracers having different diffusion coefficients displayed similar breakthrough curves. Increasing the resting phase during the experiments did not lead to a significant decline of peak concentration. All these results suggest a negligible impact of matrix diffusion. However, increasing the scales of investigation during push-pull tracer tests led to a decrease of the power law slope on the late time behavior. This behavior that cannot be modeled with a transport model based on independent flow paths and indicate non-reversible heterogeneous advection. This process could be explained by the convergence of streamlines after a certain distance

  18. Naturally occurring contaminants in the Piedmont and Blue Ridge crystalline-rock aquifers and Piedmont Early Mesozoic basin siliciclastic-rock aquifers, eastern United States, 1994–2008

    Science.gov (United States)

    Chapman, Melinda J.; Cravotta, Charles A.; Szabo, Zoltan; Lindsay, Bruce D.

    2013-01-01

    Groundwater quality and aquifer lithologies in the Piedmont and Blue Ridge Physiographic Provinces in the eastern United States vary widely as a result of complex geologic history. Bedrock composition (mineralogy) and geochemical conditions in the aquifer directly affect the occurrence (presence in rock and groundwater) and distribution (concentration and mobility) of potential naturally occurring contaminants, such as arsenic and radionuclides, in drinking water. To evaluate potential relations between aquifer lithology and the spatial distribution of naturally occurring contaminants, the crystalline-rock aquifers of the Piedmont and Blue Ridge Physiographic Provinces and the siliciclastic-rock aquifers of the Early Mesozoic basin of the Piedmont Physiographic Province were divided into 14 lithologic groups, each having from 1 to 16 lithochemical subgroups, based on primary rock type, mineralogy, and weathering potential. Groundwater-quality data collected by the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Program from 1994 through 2008 from 346 wells and springs in various hydrogeologic and land-use settings from Georgia through New Jersey were compiled and analyzed for this study. Analyses for most constituents were for filtered samples, and, thus, the compiled data consist largely of dissolved concentrations. Concentrations were compared to criteria for protection of human health, such as U.S. Environmental Protection Agency (USEPA) drinking water maximum contaminant levels and secondary maximum contaminant levels or health-based screening levels developed by the USGS NAWQA Program in cooperation with the USEPA, the New Jersey Department of Environmental Protection, and Oregon Health & Science University. Correlations among constituent concentrations, pH, and oxidation-reduction (redox) conditions were used to infer geochemical controls on constituent mobility within the aquifers. Of the 23 trace-element constituents evaluated

  19. Catalytic decarboxylations of fatty acids in immature oil source rocks

    Institute of Scientific and Technical Information of China (English)

    李哲; 张再龙; 孙燕华; 劳永新; 蔺五正; 吴卫芳

    2003-01-01

    Catalytic decarboxylations of fatty acids in immature oil source rock samples were examined in this study. The rock samples were obtained from seven oil fields in China. In order to clarify the effect of each mineral matter in the rock samples, both the Fe M?ssbauer effect and the X-ray diffraction (XRD) were used to determine the relative content of each mineral in the rock samples, and the catalytic activities of several minerals like clays, carbonates and pyrite were determined. The Fe M?ssbauer effect and the XRD studies show that clays are the main mineral components in the rock samples except for the samples from Biyang and Jianghan in which the main mineral component is ankerite. The other mineral components include calcite, plagioclase, quartz, feldspar, siderite, aragonite, pyrite, analcime, pyroxene and anhydrite. The studies of the catalytic decarboxylations of fatty acids suggest that carbonates and pyrite can make much greater contributions to the catalytic activities of the rock samples than clays. It is found that the overall catalytic activities of the rock samples are well related to the relative contents and the catalytic activities of clays, carbonates and pyrite in the rock samples.

  20. Evaluation of geologic and geophysical techniques for surface-to-subsurface projections of geologic characteristics in crystalline rock

    International Nuclear Information System (INIS)

    Granitic and gneissic rock complexes are being considered for their potential to contain and permanently isolate high-level nuclear waste in a deep geologic repository. The use of surface geologic and geophysical techniques has several advantages over drilling and testing methods for geologic site characterization in that the techniques are typically less costly, provide data over a wider area, and do not jeopardize the physical integrity of a potential repository. For this reason, an extensive literature review was conducted to identify appropriate surface geologic and geophysical techniques that can be used to characterize geologic conditions in crystalline rock at proposed repository depths of 460 to 1,220 m. Characterization parameters such as rock quality; fracture orientation, spacing; and aperture; depths to anomalies; degree of saturation; rock body dimensions; and petrology are considered to be of primary importance. Techniques reviewed include remote sensing, geologic mapping, petrographic analysis, structural analysis, gravity and magnetic methods, electrical methods, and seismic methods. Each technique was reviewed with regard to its theoretical basis and field application; geologic parameters that can be evaluated; advantages and limitations, and, where available, case history applications in crystalline rock. Available information indicates that individual techniques provide reliable information on characteristics at the surface, but have limited success in projections to depths greater that approximately 100 m. A combination of integrated techniques combines with data from a limited number of boreholes would significantly improve the reliability and confidence of early characterization studies to provide qualitative rock body characteristics for region-to-area and area-to-site selection evaluations. 458 refs., 32 figs., 14 tabs

  1. Drip Sealing Grouting of Tunnels in Crystalline Rock: Conceptualisation and Technical Strategies

    Energy Technology Data Exchange (ETDEWEB)

    Butron, Christian

    2012-07-01

    A conceptual model of the groundwater hydraulic conditions around the tunnel contour in ancient brittle crystalline rocks has been developed and verified. The general aim has been to reach an understanding of the groundwater conditions in and close to the tunnel roof where dripping takes place and to propose technical and practical strategies for waterproofing. Dripping is accompanied by ice growth and icicle formation in cold regions, creating additional problems such as shotcrete fall-outs, icicle fall-outs, damage to vehicles, damage to trains, etc. The methodology for the development of the conceptual model is based mainly on transmissivity determinations from short-duration hydraulic tests and analyses of the connectivity of the fracture structure by means of semi-variogram analysis. The determination of the dimensionality of the flow in the fractures has also been found to be essential in order to describe the conductive system. This conceptual model describes the fracture systems as a combination of transmissive patches (2D-flow fractures) connected by less pervious channels (1D-flow fractures). It provides an understanding of the heterogeneity and connectivity of the fracture network and thus the groundwater conditions, not only in the roof but also around the tunnel contour. The pre-excavation grouting design process used in the tunnelling projects followed a structured approach and the evaluation showed that the grouting design reduced the inflow and fulfilled the environmental demands. However, dripping remained, making its characterisation very important when proposing a possible solution for its control. It is proposed that the remaining dripping comes from a channelised system that has been left unsealed and which would be extremely difficult to intersect with future boreholes, as well as from some ungrouted fractures with inconvenient orientations. Geomembrane lining and post-excavation grouting are possible solutions, although particular attention

  2. Used fuel repository post-closure safety assessment in crystalline rock

    International Nuclear Information System (INIS)

    The Nuclear Waste Management Organization (NWMO) is responsible for the implementation of Adaptive Phased Management (APM), the federally-approved plan for safe long-term management of Canada's used nuclear fuel. Under the APM plan, used nuclear fuel will ultimately be placed within a deep geological repository in a suitable rock formation. The repository and its surroundings comprise a system that is designed to protect people and the environment through multiple barriers. These barriers include ceramic used fuel, long-lived corrosion-resistant containers, engineered sealing materials and the surrounding geosphere. A site selection process is currently under way to identify a safe site in an informed and willing host community. The process of site selection will take several years. As potentially suitable sites are identified in interested communities, detailed field studies and geo-scientific site characterisation activities will be conducted to assess whether the multi-barrier repository concept could be safely implemented to meet rigorous regulatory requirements. At this early stage in the process, before specific sites have been identified for examination, it is useful to conduct generic studies to illustrate the long-term performance and safety of the multi-barrier repository system within various geological settings. This paper summarises an illustrative case study of the current multi-barrier design and post-closure safety of a deep geological repository in a hypothetical crystalline Canadian Shield setting (NWMO, 2012). The purpose of this case study is to present a post-closure safety assessment methodology to illustrate how Canadian Nuclear Safety Commission (CNSC) expectations, documented in CNSC Guide G-320, Assessing the Long Term Safety of Radioactive Waste Management, are satisfied (CNSC, 2006). The approach is also consistent with international recommendations for the preparation of a safety case (IAEA, 2012), but this study specifically focusses

  3. Drip Sealing Grouting of Tunnels in Crystalline Rock: Conceptualisation and Technical Strategies

    International Nuclear Information System (INIS)

    A conceptual model of the groundwater hydraulic conditions around the tunnel contour in ancient brittle crystalline rocks has been developed and verified. The general aim has been to reach an understanding of the groundwater conditions in and close to the tunnel roof where dripping takes place and to propose technical and practical strategies for waterproofing. Dripping is accompanied by ice growth and icicle formation in cold regions, creating additional problems such as shotcrete fall-outs, icicle fall-outs, damage to vehicles, damage to trains, etc. The methodology for the development of the conceptual model is based mainly on transmissivity determinations from short-duration hydraulic tests and analyses of the connectivity of the fracture structure by means of semi-variogram analysis. The determination of the dimensionality of the flow in the fractures has also been found to be essential in order to describe the conductive system. This conceptual model describes the fracture systems as a combination of transmissive patches (2D-flow fractures) connected by less pervious channels (1D-flow fractures). It provides an understanding of the heterogeneity and connectivity of the fracture network and thus the groundwater conditions, not only in the roof but also around the tunnel contour. The pre-excavation grouting design process used in the tunnelling projects followed a structured approach and the evaluation showed that the grouting design reduced the inflow and fulfilled the environmental demands. However, dripping remained, making its characterisation very important when proposing a possible solution for its control. It is proposed that the remaining dripping comes from a channelised system that has been left unsealed and which would be extremely difficult to intersect with future boreholes, as well as from some ungrouted fractures with inconvenient orientations. Geomembrane lining and post-excavation grouting are possible solutions, although particular attention

  4. Taxonomically and functionally diverse microbial communities in deep crystalline rocks of the Fennoscandian shield

    OpenAIRE

    Nyyssönen, Mari; Hultman, Jenni; Ahonen, Lasse; Kukkonen, Ilmo; Paulin, Lars; Laine, Pia; Itävaara, Merja; Auvinen, Petri

    2013-01-01

    Microbial life in the nutrient-limited and low-permeability continental crystalline crust is abundant but remains relatively unexplored. Using high-throughput sequencing to assess the 16S rRNA gene diversity, we found diverse bacterial and archaeal communities along a 2516-m-deep drill hole in continental crystalline crust in Outokumpu, Finland. These communities varied at different sampling depths in response to prevailing lithology and hydrogeochemistry. Further analysis by shotgun metageno...

  5. Mechanical Study on the Exploitation of Groundwater Resources in Crystalline Rocks - Examples of Hoping and Kinmen areas, Taiwan

    Science.gov (United States)

    WU, Z. W.; Yeh, E. C.; Chen, P. C.; Lin, C. K.; Lin, W.; Huang, S. Y.

    2015-12-01

    Intact crystalline rocks of low porosity possess lower water storage. Conversely, fractured crystalline rocks contain higher groundwater resources. Therefore, knowledge of distribution and characteristics of fractures is essential to the exploitation of groundwater resources in crystalline rocks. This research makes crystalline rocks in Hoping and Kinmen areas of Taiwan as examples to integrates previous studies of distribution and attitude of fractures and in-situ stress from surface survey and underground study for estimating the tendencies of slip and dilation of fractures in terms of geomechanics, understanding the characteristics of potential fluid conduits, and benefiting the exploitation and development of groundwater resources. The formations in downstream area of Hoping River contain late Paleozoic to Mesoic meta-granites and marbles, and few alluvium strata. Kinmen island closed to SE Chain is located in Pingtan-Dongshan Metamorphic Belt of Late Yanshan orogeny. The formations contain Mesozoic granite, gneiss, various dikes, and some alluviums. Previous studies had conducted experiments of anelastic strain recovery on retrieved cores in Hoping. The results show that the maximum principal stress is vertical and the horizontal minimum stress is in NE-SW orientation, indicating a normal faulting stress regime with NE-SW extension. Most fractures are in E-W and N-S orientations. Results of hydraulic fracturing experiments in Kinmen display the maximum and intermediate stress is in NW-SE orientation and vertical, respectively, suggesting strike-slip faulting regime with NE-SW extension. Most fractures are in E-W and NE-SW orientations and some are in other orientations. Because of various attitudes and distributions of fractures, origin of fluid conduits is not easy to investigate and predict. Based on in-situ stress data, strikes of predicted fluid conduits in Hoping area is N-S and NW-SE while in Kinmen area is in N-S. Analysis of well logging data and

  6. Geotechnical assessment and instrumentation needs for nuclear waste isolation in crystalline and argillaceous rocks

    International Nuclear Information System (INIS)

    To evaluate the state-of-the-art, research needs, and research priorities related to waste disposal in largely impermeable rocks, scientists and engineers working on geologic aspects of nuclear waste disposal were brought together. This report and recommendations are the proceedings from that symposium. Three panels were organized on rock properties, fracture hydrology, and geochemistry. Panel discussions and recommendations are presented

  7. DEVELOPMENT OF THE SWEDISH DEEP REPOSITORY FOR SPENT NUCLEAR FUEL IN CRYSTALLINE HOST ROCK

    International Nuclear Information System (INIS)

    The Swedish Nuclear Fuel and Waste Management Company, SKB, has developed a system that ensures the safe handling of all kinds of radioactive waste from the Swedish nuclear power plants for a long time period ahead. The keystones of this system are: A transport system with the ship M/S Sigyn which has been in operation since 1983. A central interim storage facility for spent nuclear fuel, CLAB, in operation since 1985. A final repository for short-lived, low and intermediate level waste, SFR, in operation since 1988. In Sweden, the preferred method for final disposal of spent fuel is to encapsulate it in copper canisters and dispose them in a deep geological repository in crystalline host rock. SKB is planning to build an encapsulation plant adjacent to the central storage for spent fuel, CLAB. The siting for the deep repository has not yet been selected. A siting program with feasibility studies was completed in 2001. Early 2002 SKB received the necessary permits to start the site investigation at two potential sites for siting of the deep repository in Sweden. The site investigation at these sites started early 2002 and will be completed during 2007. Over the years, a number of generic studies of the layout of the operational area(s) above ground and underground facilities have been performed. During the site investigation phase the deep repository will be developed to conceptual design status and a number of design studies will be performed. These design studies are called Design Justification Statements (DJS). One important DJS is the selection of access routes from the ground level to the disposal level at tentatively 500 m depth and that study will be completed shortly. The repository design and layout of the disposal areas will be based on site specific conditions and results from demonstration of handling and equipment for canisters, buffer and backfilling. Some of these demonstrations have already been performed at Dspv HRL but additional development and

  8. Geochemistry of Crystalline Rocks from the East of the Upper East Region of Ghana

    OpenAIRE

    K.B. Pelig-Ba

    2012-01-01

    Selected rock samples were collected from outcrops from the eastern part of the Upper East Region with the aim of determining their chemical composition and classification. Samples were obtained from granitoids and the Birrimian formation located in Bongo, Talensi-Nabdam, Bawku West and Garu-Tempane Districts. Rocks were identified mineralogically using hand lenses. The composition of the samples was determined using X-Ray Fluorescence (XRF) after which several quantitative and qualitative te...

  9. Annotated bibliography of selected reports relating to the isolation of nuclear waste in crystalline rock

    International Nuclear Information System (INIS)

    BMI/OCRD-29 is an annotated bibliography of published reports that have been produced for the US Department of Energy Crystalline Repository Project Office or the Swedish-American Cooperative Program on Radioactive Waste Storage in Mined Caverns. This document consists of a main report listing of citations and abstracts and a topical index

  10. Stability and predictability in younger crystalline rock system: Japanese Islands case

    International Nuclear Information System (INIS)

    The Japanese Islands consist of igneous, sedimentary, and metamorphic rocks ranging in age from Paleozoic to Cenozoic. Among these, Carboniferous to Paleogene rocks occupy about 60% of the total area of the Japanese Islands. It should be noted that Quaternary volcanic rocks occupy only about 9% of the total area, although Quaternary volcanoes occur throughout the Japanese Islands. Long-term stability and predictability in the rock system are discussed in terms of volcanic activity, active faulting, and plate motion. Volcanic activity in the Japanese Islands is intimately related to subduction of the Pacific Plate and the Philippine Sea Plate. The volcanic front related to the Pacific and the Philippine Sea plates has been essentially fixed since about 6 Ma. The main active faults, which are distributed sporadically throughout the Japanese Islands, number about 150 and have been extensively investigated. The modes of the Pacific Plate and the Philippine Sea Plate have been essentially invariable since 10 Ma and 6 Ma, respectively. These lines of evidence imply that volcanism and tectonism in the Japanese Islands will scarcely change for hundreds of thousands of years into the future. It is clear that many places suitable for geological disposal will be present in this rock system. (author)

  11. REFRACTOMETRY AND TEXTURES OF METHYL-CYANOETHYL CELLULOSE/DICHLOROACETIC ACID LIQUID CRYSTALLINE SOLUTIONS

    Institute of Scientific and Technical Information of China (English)

    HUANG Yong; WU Bingkun

    1992-01-01

    An Abbe' refractometer with a rotatable polarizer mounted on the eyepiece is used for determining the two principal refractive indices of methyl-cyanoethyl cellulose/dichloroacetic acid liquid crystalline solutions. The critical concentration where the mesophase appears can be determined according to the variation of the increment of the refractive index with the concentration. Mesophase textures of the liquid crystalline solutions are observed and the influence of the concentration on mesophase textures is also discussed.

  12. Taxonomically and functionally diverse microbial communities in deep crystalline rocks of the Fennoscandian shield.

    Science.gov (United States)

    Nyyssönen, Mari; Hultman, Jenni; Ahonen, Lasse; Kukkonen, Ilmo; Paulin, Lars; Laine, Pia; Itävaara, Merja; Auvinen, Petri

    2014-01-01

    Microbial life in the nutrient-limited and low-permeability continental crystalline crust is abundant but remains relatively unexplored. Using high-throughput sequencing to assess the 16S rRNA gene diversity, we found diverse bacterial and archaeal communities along a 2516-m-deep drill hole in continental crystalline crust in Outokumpu, Finland. These communities varied at different sampling depths in response to prevailing lithology and hydrogeochemistry. Further analysis by shotgun metagenomic sequencing revealed variable carbon and nutrient utilization strategies as well as specific functional and physiological adaptations uniquely associated with specific environmental conditions. Altogether, our results show that predominant geological and hydrogeochemical conditions, including the existence and connectivity of fracture systems and the low amounts of available energy, have a key role in controlling microbial ecology and evolution in the nutrient and energy-poor deep crustal biosphere. PMID:23949662

  13. Geochemistry of Crystalline Rocks from the East of the Upper East Region of Ghana

    Directory of Open Access Journals (Sweden)

    K.B. Pelig-Ba

    2012-05-01

    Full Text Available Selected rock samples were collected from outcrops from the eastern part of the Upper East Region with the aim of determining their chemical composition and classification. Samples were obtained from granitoids and the Birrimian formation located in Bongo, Talensi-Nabdam, Bawku West and Garu-Tempane Districts. Rocks were identified mineralogically using hand lenses. The composition of the samples was determined using X-Ray Fluorescence (XRF after which several quantitative and qualitative techniques were employed to analyse the data. Some of these techniques included physical examination, Chemical Alteration Index (CIA, scatter plots, discrimination diagrams and Aluminium Saturation Index (ASI. The mineralogical analysis showed that the rocks generally contained K-feldspar, plagioclase, muscovite, hornblende, quartz and biotite as major minerals. Physical examination revealed that samples had undergone some alteration that was not evident at the time of sampling and this was confirmed by calculations using the Chemical Index of Alteration (CIA. The CIA values of the fresh rocks ranged from 70 to 125 suggesting that the samples had undergone intensive alteration. Scatter plots and discrimination diagrams suggested that the samples were not of basaltic origin but were thoeleiitic in character. The Aluminium Saturation Index (ASI revealed that most samples were metaluminus and that the majority of samples were sub-alkaline and therefore basic in character.

  14. Study on equivalent continuum modeling with crack tensor on crystalline rock

    International Nuclear Information System (INIS)

    The Crack tensor model which is a kind of equivalent continuum model has been studied in rock mechanical investigation in the MIU. The fractured rock mass is modeled as the elastic continuum model with the crack tensor. In this study, crack tensor based on the geological observation in the MIU project was calculated, and REV (Representative Elementary Volume) in the shafts and research galleries was studied based on the relative error of the crack tensor. The correlation between the crack density, the trace length of crack and the trace of crack tensor and the rock mass classification was also studied. The results are as follows: 1) The correlation between the trace of the crack tensor and the rock mass classification was negative at the research gallery. 2) Some observance zones were set in the ventilation shaft and the research gallery, and the convergence of the relative error in the each observance zone was studied based on the crack tensor. The convergence of the relative error was faster in the research gallery than in the ventilation shaft. 3) The method of calculation of the trace length of the crack on curved wall was proposed. The further studies based on the crack tensor model will be more accurate than the past studies by the proposed method. (author)

  15. Water vapour permeability of poly(lactic acid): Crystallinity and the tortuous path model

    Science.gov (United States)

    Duan, Z.; Thomas, N. L.

    2014-02-01

    The water vapour transmission rates (WVTR) through samples of polylactic acid of different crystallinities have been measured. Three different grades of commercial poly(lactic acid) (PLA) were used with different ratios of L-lactide and D-lactide to give a range of crystallinities from 0% to 50%. Sheets of PLA were prepared by melt compounding followed by compression moulding and annealing at different temperatures and for different times to give the range of crystallinities required. Crystallinity was measured by differential scanning calorimetry and the morphology of the samples was observed under crossed polars in a transmitted light microscope. Water vapour transmission rates through the films were measured at 38 °C and at a relative humidity of 90%. It was found that the measured values of WVTR decreased linearly with increasing crystallinity of the PLA from 0% to 50%. The results are discussed in terms of the effect of crystallinity on solubility and shown to fit the "Tortuous Path Model." The model was also successfully used to explain published data on water permeability of polyethylene terephthalate.

  16. Study of fractures in Precambrian crystalline rocks using field technique in and around Balarampur, Purulia district, West Bengal, India

    Indian Academy of Sciences (India)

    Monalisa Mitra; Tapas Acharya

    2015-12-01

    Location of recharge zone in Precambrian crystalline rock is still unclear. The present study attempts to perform a detailed analysis of the joints/fractures developed in a Precambrian metamorphic terrain in and around Balarampur in Purulia district of West Bengal, India using bedrock data. The analysis shows that the orientations of major fracture trends are variable along with varying lithological units and structural affinities. The application of lithology-based analysis technique identifies highly predominant fracture frequency and fracture aperture in mica schist and phyllite in the area. This property is not evident in the granite gneiss and epidiorite. The moderate to high fracture permeability value is also associated with the fractures occurring in the shear zone. Mica schist and phyllite associated with the shear zone may represent a permeable recharge zone in the region.

  17. The effect of specific surface area on radionuclide sorption on crushed crystalline rock

    Energy Technology Data Exchange (ETDEWEB)

    Hoelttae, P.; Siitari-Kauppi, M.; Huikuri, P. [Univ. of Helsinki (Finland). Dept. of Chemistry; Lindberg, A. [Geological Survey of Finland, Espoo (Finland); Hautojaervi, A. [VTT Energy (Finland)

    1997-12-31

    The sorption of sodium ({sup 22}Na), calcium ({sup 45}Ca) and strontium ({sup 85}Sr) was studied on mica gneiss, unaltered, moderately altered and strongly altered tonalite samples taken from hole SY-KR7 drilled in the Syyry area in Sievi, Western Finland. The crushed rock samples were sieved into six fractions from 71 {micro}m to 1,250 {micro}m. A proportional mineral composition for the different fractions were estimated by X-ray diffraction. The specific fraction surface areas were determined by the BET nitrogen adsorption method. The fractal method was applied to characterize rocks and to describe quantitatively surface irregularity. The mass distribution ratio values for each fraction were determined using the static batch method. The sorption of tracers onto different minerals was observed using rock thin sections. K{sub d}-values calculated from thin section K{sub a}-values and K{sub d}-values obtained from batch experiments were in good agreement. Mass distribution ratios for different size fractions are given, and the effect of the specific surface area is discussed. Owing to larger specific surface areas considerably higher sorption on smaller fractions was found for altered tonalities.

  18. Mineralogical, chemical, and physical properties of the regolith overlying crystalline rocks, Fairfax County, Virginia: a preliminary report

    Science.gov (United States)

    Leo, Gerhard W.; Pavich, M.J.; Obermeier, Stephen F.

    1977-01-01

    Undisturbed cores of saprolite developed on crystalline rocks of the Piedmont Province in Fairfax County, Virginia have been obtained using a combination of Shelby tubes, Denison sampler, and modified diamond core-drilling. The principal purpose of the core study is to correlate variations in chemistry, mineralogy and texture with engineering properties throughout the weathering profile. Coring sites were chosen to obtain a maximum depth of weathering on diverse lithologies. The rocks investigated include pelitic schist, metagraywacke, granite, diabase and serpentinite. Four to twelve samples per core were selected, depending on thickness of 1) the weathering profile (from about 1 m in serpentinite to more than 30 m in pelitic schist) and on 2) megascopic changes in saprolite character for analysis of petrography, texture, clay mineralogy andd major element chemistry. Shear strength and compressibility were determined on corresponding segments of core. Standard penetration tests were performed adjacent to coring sites to evaluate engineering properties in situ. Geochemical changes of saprolite developed from each rock type follow predictable trends from fresh rock to soil profile, with relative Increases in Si, Ti, Al, Fe3+ and H20; variable K; and relative loss of Fe 2+, Mg, Ca, and Na. These variations are more pronounced in the weathering profiles over mafic and ultramafic rocks than metagraywacke. Clay minerals in granite, schist and metagraywacke saprolite are kaolinite, dioctahedral vermiculite, interlayered micavermiculite, and minor illite. Gibbsite is locally developed in near-surface samples of schist. Standard penetration test data for the upper 7 m of saprolite over schist and metagraywacke suggest alternations between stronger and weaker horizons than probably reflect variations in lithology including the presence of quartz lenses. Results for granite saprolite are most consistent but indicate lower strength. Shear strength increases fairly regularly

  19. Impact-generated endolithic habitat within crystalline rocks of the Haughton impact structure, Devon Island, Canada.

    Science.gov (United States)

    Pontefract, Alexandra; Osinski, Gordon R; Cockell, Charles S; Moore, Casey A; Moores, John E; Southam, Gordon

    2014-06-01

    The colonization of rocks by endolithic communities is an advantageous trait, especially in environments such as hot or cold deserts, where large temperature ranges, low water availability, and high-intensity ultraviolet radiation pose a significant challenge to survival and growth. On Mars, similar conditions (albeit more extreme) prevail. In these environments, meteorite impact structures could provide refuge for endolithic organisms. Though initially detrimental to biology, an impact event into a rocky body can favorably change the availability and habitability of a substrate for endolithic organisms, which are then able to (re)colonize microfractures and pore spaces created during the impact. Here, we show how shocked gneisses from the Haughton impact structure, Devon Island, Canada, offer significant refuge for endolithic communities. A total of 28 gneiss samples representing a range of shock states were analyzed, collected from in situ, stable field locations. For each sample, the top centimeter of rock was examined with confocal scanning laser microscopy, scanning electron microscopy, and bright-field microscopy to investigate the relationship of biomass with shock level, which was found to correlate generally with increased shock state and particularly with increased porosity. We found that gneisses, which experienced pressures between 35 and 60 GPa, provide the most ideal habitat for endolithic organisms. PMID:24926727

  20. Predictive permeability model of faults in crystalline rocks; verification by joint hydraulic factor (JH) obtained from water pressure tests

    Science.gov (United States)

    Barani, Hamidreza Rostami; Lashkaripour, Gholamreza; Ghafoori, Mohammad

    2014-08-01

    In the present study, a new model is proposed to predict the permeability per fracture in the fault zones by a new parameter named joint hydraulic factor (JH). JH is obtained from Water Pressure Test (WPT) and modified by the degree of fracturing. The results of JH correspond with quantitative fault zone descriptions, qualitative fracture, and fault rock properties. In this respect, a case study was done based on the data collected from Seyahoo dam site located in the east of Iran to provide the permeability prediction model of fault zone structures. Datasets including scan-lines, drill cores, and water pressure tests in the terrain of Andesite and Basalt rocks were used to analyse the variability of in-site relative permeability of a range from fault zones to host rocks. The rock mass joint permeability quality, therefore, is defined by the JH. JH data analysis showed that the background sub-zone had commonly fracture, whereas the fault core had permeability characteristics nearly as low as the outer damage zone, represented by 8 Lu (1.3 ×10-4 m 3/s) per fracture, with occasional peaks towards 12 Lu (2 ×10-4 m 3/s) per fracture. The maximum JH value belongs to the inner damage zone, marginal to the fault core, with 14-22 Lu (2.3 ×10-4-3.6 ×10-4 m 3/s) per fracture, locally exceeding 25 Lu (4.1 ×10-4 m 3/s) per fracture. This gives a proportional relationship for JH approximately 1:4:2 between the fault core, inner damage zone, and outer damage zone of extensional fault zones in crystalline rocks. The results of the verification exercise revealed that the new approach would be efficient and that the JH parameter is a reliable scale for the fracture permeability change. It can be concluded that using short duration hydraulic tests (WPTs) and fracture frequency (FF) to calculate the JH parameter provides a possibility to describe a complex situation and compare, discuss, and weigh the hydraulic quality to make predictions as to the permeability models and

  1. Predictive permeability model of faults in crystalline rocks; verification by joint hydraulic factor (JH) obtained from water pressure tests

    Indian Academy of Sciences (India)

    Hamidreza Rostami Barani; Gholamreza Lashkaripour; Mohammad Ghafoori

    2014-08-01

    In the present study, a new model is proposed to predict the permeability per fracture in the fault zones by a new parameter named joint hydraulic factor (JH). JH is obtained from Water Pressure Test WPT) and modified by the degree of fracturing. The results of JH correspond with quantitative fault zone descriptions, qualitative fracture, and fault rock properties. In this respect, a case study was done based on the data collected from Seyahoo dam site located in the east of Iran to provide the permeability prediction model of fault zone structures. Datasets including scan-lines, drill cores, and water pressure tests in the terrain of Andesite and Basalt rocks were used to analyse the variability of in-site relative permeability of a range from fault zones to host rocks. The rock mass joint permeability quality, therefore, is defined by the JH. JH data analysis showed that the background sub-zone had commonly > 3 Lu (less of 5 × 10−5 m3/s) per fracture, whereas the fault core had permeability characteristics nearly as low as the outer damage zone, represented by 8 Lu (1.3 × 10−4 m3/s) per fracture, with occasional peaks towards 12 Lu (2 × 10−4 m3/s) per fracture. The maximum JH value belongs to the inner damage zone, marginal to the fault core, with 14–22 Lu (2.3 × 10−4 –3.6 × 10−4 m3/s) per fracture, locally exceeding 25 Lu (4.1 × 10−4 m3/s) per fracture. This gives a proportional relationship for JH approximately 1:4:2 between the fault core, inner damage zone, and outer damage zone of extensional fault zones in crystalline rocks. The results of the verification exercise revealed that the new approach would be efficient and that the JH parameter is a reliable scale for the fracture permeability change. It can be concluded that using short duration hydraulic tests (WPTs) and fracture frequency (FF) to calculate the JH parameter provides a possibility to describe a complex situation and compare, discuss, and weigh the hydraulic quality to make

  2. Silicon Isotope Fractionation During Acid Water-Igneous Rock Interaction

    Science.gov (United States)

    van den Boorn, S. H.; van Bergen, M. J.; Vroon, P. Z.

    2007-12-01

    Silica enrichment by metasomatic/hydrothermal alteration is a widespread phenomenon in crustal environments where acid fluids interact with silicate rocks. High-sulfidation epithermal ore deposits and acid-leached residues at hot-spring settings are among the best known examples. Acid alteration acting on basalts has also been invoked to explain the relatively high silica contents of the surface of Mars. We have analyzed basaltic-andesitic lavas from the Kawah Ijen volcanic complex (East Java, Indonesia) that were altered by interaction with highly acid (pH~1) sulfate-chloride water of its crater lake and seepage stream. Quantitative removal of major elements during this interaction has led to relative increase in SiO2 contents. Our silicon isotope data, obtained by HR-MC-ICPMS and reported relative to the NIST RM8546 (=NBS28) standard, show a systematic increase in &δ&&30Si from -0.2‰ (±0.3, 2sd) for unaltered andesites and basalts to +1.5‰ (±0.3, 2sd) for the most altered/silicified rocks. These results demonstrate that silicification induced by pervasive acid alteration is accompanied by significant Si isotope fractionation, so that alterered products become isotopically heavier than the precursor rocks. Despite the observed enrichment in SiO2, the rocks have experienced an overall net loss of silicon upon alteration, if Nb is considered as perfectly immobile. The observed &δ&&30Si values of the alteration products appeared to correlate well with the inferred amounts of silicon loss. These findings would suggest that &28Si is preferentially leached during water-rock interaction, implying that dissolved silica in the ambient lake and stream water is isotopically light. However, layered opaline lake sediments, that are believed to represent precipitates from the silica-saturated water show a conspicuous &30Si-enrichment (+1.2 ± 0.2‰). Because anorganic precipitation is known to discriminate against the heavy isotope (e.g. Basile- Doelsch et al., 2006

  3. Review of geoscientific data of relevance to disposal of spent nuclear fuel in deep boreholes in crystalline rock

    Energy Technology Data Exchange (ETDEWEB)

    Marsic, Nico; Grundfelt, Bertil [Kemakta Konsult AB, Stockholm (Sweden)

    2013-09-15

    In this report a compilation of recent geoscientific data of relevance to disposal of spent nuclear fuel in deep boreholes in Sweden is presented. The goal of the study has been limited to identifying and briefly describing such geoscientific information of relevance to disposal in deep boreholes that was not available at the time when previous compilations were made. Hence, the study is not to be regarded as a general up-date of new geoscientific information. Disposal of spent nuclear fuel in deep boreholes has been studied in Sweden since the second half of the 1980s. The currently studied concept has been proposed by Sandia National Laboratories in the USA. In this concept the spent fuel elements are encapsulated in cylindrical steel canisters that are joined together in strings of 40 canisters and lowered into five kilometres deep boreholes. Ten such strings are stacked between three and five kilometres depth separated from each other by concrete plugs. The study started with a review of boreholes that have been reported after the previous reviews that were published in 1998 and 2004. A total of 12 boreholes of potential relevance were identified. Further study showed that only four out of these holes penetrated into crystalline rock. Two of these were deemed to be less relevant because they were drilled in areas with much higher geothermal gradient than in the parts of the Fennoscandian shield that realistically could host a Swedish deep borehole repository. Of the two remaining boreholes, only one, a geoscientific hole drilled at Outokumpu in Finland, is associated with a reasonably complete geoscientific data set. It is worth mentioning that a large part of this hole is drilled through meta sedimentary rock (mica schist) rather than granitic rock. The information collected and reviewed has been gathered under the headings hydraulic conditions, geothermal conditions, hydrogeochemical conditions, bacteriological activity and rock mechanical properties. Only

  4. Exceptionally crystalline and conducting acid doped polyaniline films by level surface assisted solution casting approach

    Science.gov (United States)

    Puthirath, Anand B.; Methattel Raman, Shijeesh; Varma, Sreekanth J.; Jayalekshmi, S.

    2016-04-01

    Emeraldine salt form of polyaniline (PANI) was synthesized by chemical oxidative polymerisation method using ammonium persulfate as oxidant. Resultant emeraldine salt form of PANI was dedoped using ammonia solution and then re-doped with camphor sulphonic acid (CSA), naphthaline sulphonic acid (NSA), hydrochloric acid (HCl), and m-cresol. Thin films of these doped PANI samples were deposited on glass substrates using solution casting method with m-cresol as solvent. A level surface was employed to get homogeneous thin films of uniform thickness. Detailed X-ray diffraction studies have shown that the films are exceptionally crystalline. The crystalline peaks observed in the XRD spectra can be indexed to simple monoclinic structure. FTIR and Raman spectroscopy studies provide convincing explanation for the exceptional crystallinity observed in these polymer films. FESEM and AFM images give better details of surface morphology of doped PANI films. The DC electrical conductivity of the samples was measured using four point probe technique. It is seen that the samples also exhibit quite high DC electrical conductivity, about 287 S/cm for CSA doped PANI, 67 S/cm for NSA doped PANI 65 S/cm for HCl doped PANI, and just below 1 S/cm for m-cresol doped PANI. Effect of using the level surface for solution casting is studied and correlated with the observed crystallinity.

  5. Single crystalline graphene synthesized by thermal annealing of humic acid over copper foils

    Science.gov (United States)

    Beall, Gary W.; Duraia, El-Shazly M.; Yu, Q.; Liu, Z.

    2014-02-01

    Production of graphene by thermal annealing on copper foil substrates has been studied with different sources of carbon. The three carbon sources include humic acid derived from leonardite, graphenol, and activated charcoal. Hexagonal single crystalline graphene has been synthesized over the copper foil substrates by thermal annealing of humic acid, derived from leonardite, in argon and hydrogen atmosphere (Ar/H2=20). The annealing temperature was varied between 1050 °C and 1100 °C at atmospheric pressure. Samples have been investigated using scanning electron microscope (SEM) and Raman spectroscopy. At lower temperatures the thermal annealing of the three carbon sources used in this study produces pristine graphene nanosheets which cover almost the whole substrate. However when the annealing temperature has been increased up to 1100 °C, hexagonal single crystalline graphene have been observed only in the case of the humic acid. Raman analysis showed the existence of 2D band around 2690 cm-1.

  6. The effect of acid hydrolysis pretreatment on crystallinity and solubility of kenaf cellulose membrane

    Energy Technology Data Exchange (ETDEWEB)

    Saidi, Anis Syuhada Mohd; Zakaria, Sarani; Chia, Chin Hua; Jaafar, Sharifah Nabihah Syed; Padzil, Farah Nadia Mohammad [School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor (Malaysia)

    2015-09-25

    Cellulose was extracted from kenaf core pulp (KCP) by series of bleaching steps in the sequence (DEED) where D and E are referred as acid and alkali treatment. The bleached kenaf pulp (BKCP) is then pretreated with acid hydrolysis at room temperature for 1 and 3 h respectively. The pretreated cellulose is dissolved in lithium hydroxide/urea (LiOH/urea) and cellulose solution produced was immersed in distilled water bath. BKCP without treatment was also conducted for comparison purpose. The effects of acid hydrolysis pretreatment on solubility and crystallinity are investigated. Higher solubility of cellulose solution is achieved for treated samples. Cellulose II formation and crystallinity index of the cellulose membrane were determined by X-ray diffraction (XRD)

  7. The effect of acid hydrolysis pretreatment on crystallinity and solubility of kenaf cellulose membrane

    Science.gov (United States)

    Saidi, Anis Syuhada Mohd; Zakaria, Sarani; Chia, Chin Hua; Jaafar, Sharifah Nabihah Syed; Padzil, Farah Nadia Mohammad

    2015-09-01

    Cellulose was extracted from kenaf core pulp (KCP) by series of bleaching steps in the sequence (DEED) where D and E are referred as acid and alkali treatment. The bleached kenaf pulp (BKCP) is then pretreated with acid hydrolysis at room temperature for 1 and 3 h respectively. The pretreated cellulose is dissolved in lithium hydroxide/urea (LiOH/urea) and cellulose solution produced was immersed in distilled water bath. BKCP without treatment was also conducted for comparison purpose. The effects of acid hydrolysis pretreatment on solubility and crystallinity are investigated. Higher solubility of cellulose solution is achieved for treated samples. Cellulose II formation and crystallinity index of the cellulose membrane were determined by X-ray diffraction (XRD).

  8. The first deep heat flow determination in crystalline basement rocks beneath the Western Canadian Sedimentary Basin

    Science.gov (United States)

    Majorowicz, Jacek; Chan, Judith; Crowell, James; Gosnold, Will; Heaman, Larry M.; Kück, Jochem; Nieuwenhuis, Greg; Schmitt, Douglas R.; Unsworth, Martyn; Walsh, Nathaniel; Weides, Simon

    2014-05-01

    Heat flow (Q) determined from bottom-hole temperatures measured in oil and gas wells in Alberta show a large scatter with values ranging from 40 to 90 mW m-2. Only two precise measurements of heat flow were previously reported in Alberta, and were made more than half a century ago. These were made in wells located near Edmonton, Alberta, and penetrated the upper kilometre of clastic sedimentary rocks yielding heat flows values of 61 and 67 mW m-2 (Garland & Lennox). Here, we report a new precise heat flow determination from a 2363-m deep well drilled into basement granite rocks just west of Fort McMurray, Alberta (the Hunt Well). Temperature logs acquired in 2010-2011 show a significant increase in the thermal gradient in the granite due to palaeoclimatic effects. In the case of the Hunt Well, heat flow at depths >2200 m is beyond the influence of the glacial-interglacial surface temperatures. Thermal conductivity and temperature measurements in the Hunt Well have shown that the heat flow below 2.2 km is 51 mW m-2 (±3 mW m-2), thermal conductivity measured by the divided bar method under bottom of the well in situ like condition is 2.5 W m-1 K-1, and 2.7 W m-1 K-1 in ambient conditions), and the geothermal gradient was measured as 20.4 mK m-1. The palaeoclimatic effect causes an underestimate of heat flow derived from measurements collected at depths shallower than 2200 m, meaning other heat flow estimates calculated from basin measurements have likely been underestimated. Heat production (A) was calculated from spectral gamma recorded in the Hunt Well granites to a depth of 1880 m and give an average A of 3.4 and 2.9 μW m-3 for the whole depth range of granites down to 2263 m, based on both gamma and spectral logs. This high A explains the relatively high heat flow measured within the Precambrian basement intersected by the Hunt Well; the Taltson Magmatic Zone. Heat flow and related heat generation from the Hunt Well fits the heat flow-heat generation

  9. Crystalline structure of annealed polylactic acid and its relation to processing

    Directory of Open Access Journals (Sweden)

    2010-10-01

    Full Text Available This paper focuses on the crystalline structure of injection moulding grade poly(lactic acid (PLA and the effect of crystalline structure on the processing. The research is induced by the significant differences in crystallinity of the pure PLA resin, and the injection moulded product, and thus the reprocessing of PLA products. 2 mm thick PLA sheets were injection moulded and re-crystallized in a conventional oven at 60–140°C, for 10–60 minutes to achieve various crystalline contents. The properties of these sheets were investigated by dynamic mechanical analysis (DMA, differential scanning calorimetry (DSC, and wide angle X-ray diffraction (WAXD. In a processing plant the rejected parts are recycled and reused as raw material for further cycles, accordingly the various crystalline content PLA products were reprocessed as a resin, to investigate the processing itself. When PLA products are reprocessed, due to the adherent feature of amorphous PLA processing difficulties may occur. This adherent effect of the amorphous PLA was investigated and characterized.

  10. Probing the Texture of the Calamitic Liquid Crystalline Dimer of 4-(4-Pentenyloxybenzoic Acid

    Directory of Open Access Journals (Sweden)

    Maher A. Qaddoura

    2010-01-01

    Full Text Available The liquid crystalline dimer of 4-(4-pentenyloxybenzoic acid, a member of the n-alkoxybenzoic acid homologous series, was synthesized using potassium carbonate supported on alumina as catalyst. The acid dimer complex exhibited three mesophases; identified as nematic, smectic X1 and smectic X2. Phase transition temperatures and the corresponding enthalpies were recorded using differential scanning calorimetry upon both heating and cooling. The mesophases were identified by detailed texture observations by variable temperature polarized light microscopy. The nematic phase was distinguished by a fluid Schlieren texture and defect points (four and two brushes while the smectic phases were distinguished by rigid marble and mosaic textures, respectively.

  11. Reactive transport of uranium in fractured crystalline rock: Upscaling in time and distance.

    Science.gov (United States)

    Dittrich, Timothy M; Reimus, Paul W

    2016-01-01

    Batch adsorption and breakthrough column experiments were conducted to evaluate uranium transport through altered material that fills fractures in a granite rock system at the Grimsel Test Site in Switzerland at pH 6.9 and 7.9. The role of adsorption and desorption kinetics was evaluated with reactive transport modeling by comparing one-, two-, and three-site models. Emphasis was placed on describing long desorption tails that are important for upscaling in time and distance. The effect of increasing pH in injection solutions was also evaluated. For pH 6.9, a three-site model with forward rate constants between 0.07 and 0.8 ml g(-1) h(-1), reverse rate constants between 0.001 and 0.06 h(-1), and site densities of 1.3, 0.104, and 0.026 μmol g(-1) for 'weak/fast', 'strong/slow', and 'very strong/very slow' sites provided the best fits. For pH 7.9, a three-site model with forward rate constants between 0.05 and 0.8 mL g(-1) h(-1), reverse rate constants between 0.001 and 0.6 h(-1), and site densities of 1.3, 0.039, and 0.013 μmol g(-1) for a 'weak/fast', 'strong/slow', and 'very strong/very slow' sites provided the best fits. Column retardation coefficients (Rd) were 80 for pH 6.9 and 10.3 for pH 7.9. Model parameters determined from the batch and column experiments were used in 50 year large-scale simulations for continuous and pulse injections and indicated that a three-site model is necessary at pH 6.9, although a Kd-type equilibrium partition model with one-site was adequate for large scale predictions at pH 7.9. Batch experiments were useful for predicting early breakthrough times in the columns while column experiments helped differentiate the relative importance of sorption sites and desorption rate constants on transport.

  12. A Methodology for Confirmatory Testing of Numerical Models of Groundwater Flow and Solute Transport in Fractured Crystalline Rock

    Science.gov (United States)

    Hartley, L.; Follin, S.; Rhen, I.; Selroos, J.

    2008-12-01

    Three-dimensional, regional, numerical models of groundwater flow and solute transport in fractured crystalline rock are used for two sites in Sweden that are considered for geological disposal of spent nuclear fuel. The models are used to underpin the conceptual modeling that is based on multi-disciplinary data and include descriptions of the geometry of geological features (deformation zones and fracture networks), transient hydrological and chemical boundary conditions, strong spatial heterogeneity in the hydraulic properties, density driven flow, solute transport including rock matrix diffusion, and mixing of different water types in a palaeo-hydrogeological perspective (last 10,000 years). From a credibility point of view, comparisons between measured and simulated data are important and provide a means to address our ability to understand complex hydrogeological systems, and hence what particular applications of a hydrogeological model of a physical system that are justified, e.g. in subsequent repository performance assessment studies. For instance, it has been suggested that an understanding of the hydrochemical evolution throughout geological time is a powerful tool to predict the future evolution of groundwater flow and its chemical composition. The general approach applied in the numerical modeling was to first parameterize the deformation zones and fracture networks hydraulically using fracture and inflow data from single-hole tests. Second, the confirmatory step relies on using essentially the same groundwater flow and solute transport model in terms of grid discretization and parameter settings for matching three types of independent field data: 1) large-scale cross-hole (interference) tests, 2) long-term monitoring of groundwater levels, and 3) hydrochemical composition of fracture water and matrix pore water in deep boreholes. We demonstrate here the modelling approach of the second step - confirmatory testing - using data from the site

  13. Phosphorus release from phosphate rock and iron phosphate by low-molecular-weight organic acids

    Institute of Scientific and Technical Information of China (English)

    XU Ren-kou; ZHU Yong-guan; David Chittleborough

    2004-01-01

    Low-molecular-weight(LMW) organic acids widely exist in soils, particularly in the rhizosphere. A series of batch experiments were carried out to investigate the phosphorus release from rock phosphate and iron phosphate by Iow-molecular-weight organic acids.Results showed that citric acid had the highest capacity to solubilize P from both rock and iron phosphate. P solubilization from rock phosphate and iron phosphate resulted in net proton consumption. P release from rock phosphate was positively correlated with the pKa values. P release from iron phosphate was positively correlated with Fe-organic acid stability constants except for aromatic acids, but was not correlated with PKa. Increase in the concentrations of organic acids enhanced P solubilization from both rock and iron phosphate almost linearrly. Addition of phenolic compounds further increased the P release from iron phosphate. Initial solution pH had much more substantial effect on P release from rock phosphate than from iron phosphate.

  14. Survey of in situ testing at underground laboratories with application to geologic disposal of spent fuel waste in crystalline rock

    International Nuclear Information System (INIS)

    This report is intended for use in designing testing programs, or as backup material for the review of 'R and D 92' which will be the next three-year plan for spent fuel repository siting and characterization activities in Sweden. There are eight major topics, each of which is addressed in a chapter of around 2000 to 10000 words. The major topics are defined to capture the reasons for testing, in a way that limits overlap between chapters. Other goals of this report are to provide current information on recent or ongoing tests in crystalline rock, and to describe insights which are important but not obvious from the literature. No data are presented, but the conclusions of testing programs are summarized. The principal sources were reports (in English) produced by the laboratory projects particularly the Stripa Project (SKB), the Underground Research Laboratory in Canada (AECL), and the Grimsel Test Site in Switzerland (Nagra). Articles from refereed journals have been used in lieu of project literature where possible and appropriate. (au)

  15. A review and synthesis of international proposals for the disposal of high-level radioactive wastes into crystalline rock formations

    International Nuclear Information System (INIS)

    Examination of the broad range of international concepts for the disposal of high-level radioactive wastes into crystalline rock formations has indicated that systems based upon solid waste units provide the greatest degree of engineering control and security. Three particular disposal concepts are considered worthy of detailed evaluation. In order of priority these are:-tunnel networks with 'in-floor' waste emplacement; matrix of vertical emplacement holes drilled from the surface; tunnel networks with 'in-room' waste emplacement. A review of the international literature has shown that at least ten countries have embarked upon study programmes, but only five have developed detailed conceptual design proposals. These are:- Canada, France, Sweden, the United Kingdom, and the United States. Differing economic, environmental, historical and political circumstances have influenced the pattern of international studies and, to the uninitiated, these factors may obscure some of the relevant technical considerations. Nevertheless, a broad technical concensus is apparent in that all countries currently favour tunnel networks with 'in-floor' waste emplacement. The subject is discussed in detail. (author)

  16. Modeling of irradiated graphite (14)C transfer through engineered barriers of a generic geological repository in crystalline rocks.

    Science.gov (United States)

    Poskas, Povilas; Grigaliuniene, Dalia; Narkuniene, Asta; Kilda, Raimondas; Justinavicius, Darius

    2016-11-01

    There are two RBMK-1500 type graphite moderated reactors at the Ignalina nuclear power plant in Lithuania, and they are under decommissioning now. The graphite cannot be disposed of in a near surface repository, because of large amounts of (14)C. Therefore, disposal of the graphite in a geological repository is a reasonable solution. This study presents evaluation of the (14)C transfer by the groundwater pathway into the geosphere from the irradiated graphite in a generic geological repository in crystalline rocks and demonstration of the role of the different components of the engineered barrier system by performing local sensitivity analysis. The speciation of the released (14)C into organic and inorganic compounds as well as the most recent information on (14)C source term was taken into account. Two alternatives were considered in the analysis: disposal of graphite in containers with encapsulant and without it. It was evaluated that the maximal fractional flux of inorganic (14)C into the geosphere can vary from 10(-11)y(-1) (for non-encapsulated graphite) to 10(-12)y(-1) (for encapsulated graphite) while of organic (14)C it was about 10(-3)y(-1) of its inventory. Such difference demonstrates that investigations on the (14)C inventory and chemical form in which it is released are especially important. The parameter with the highest influence on the maximal flux into the geosphere for inorganic (14)C transfer was the sorption coefficient in the backfill and for organic (14)C transfer - the backfill hydraulic conductivity.

  17. PHARMACOKINETICS OF CEFTIOFUR CRYSTALLINE FREE ACID, A LONG-ACTING CEPHALOSPORIN, IN AMERICAN FLAMINGOS (PHOENICOPTERUS RUBER).

    Science.gov (United States)

    Kilburn, Jennifer J; Cox, Sherry K; Backues, Kay A

    2016-06-01

    Antibiotic usage is a vital component of veterinary medicine but the unique anatomy of some species can make administration difficult. The objective of this study was to determine the pharmacokinetic parameters of ceftiofur crystalline free acid (CCFA), a long-acting cephalosporin antibiotic, after parenteral administration in American flamingos ( Phoenicopterus ruber ). A dose of 10 mg/kg of CCFA was administered intramuscularly to 11 birds and blood was collected at various time points from 0 to 192 hr. Pharmacokinetic parameters for ceftiofur equivalents were determined and reached levels above minimum inhibitory concentrations of various bacterial organisms in other avian species through 96 hr in 9/11 birds. Based on these findings and comparison to other avian studies, ceftiofur crystalline free acid appears to be a long-acting antibiotic option for American flamingos. Administration of this antibiotic should be utilized in conjunction with culture and sensitivity of suspected pathogens. PMID:27468016

  18. Self-assembly of azobenzene based side-chain liquid crystalline polymer and -alkyloxybenzoic acids

    Indian Academy of Sciences (India)

    Kumarasamy Gayathri; Subramanian Balamurugan; Palaninathan Kannan

    2011-05-01

    Liquid crystalline pendant polymeric complexes have been obtained by supramolecular assembly of two mesogenic components namely, poly[4-(10-acryloyloxydecyloxy)-4'- phenylazobenzonitrile] (P10) and 4-alkyloxybenzoic acids (A7-A12). Hydrogen bond formed between carboxylic acid and cyano moiety served as molecular bridge. The polymeric complexes acquitted as undivided liquid crystalline properties exhibited stable and enantiotropic mesophases. The precursor, monomer and polymer were analysed by 1H-NMR and 13C-NMR spectroscopy. The hydrogen bonding interaction in polymer complexes (P10-A7 to P10-A12) was investigated by FT-IR spectroscopy. The thermal behaviours and textural analysis were studied by differential scanning calorimetry and polarized optical microscopy respectively.

  19. Excavation damage and disturbance in crystalline rock - results from experiments and analyses

    Energy Technology Data Exchange (ETDEWEB)

    Baeckblom, Goeran (Conrox AB, Stockholm (Sweden))

    2008-11-15

    calculations using the PHREEQC code showed that fracture precipitation is unlikely to clog the water-conducting fractures within a 10-year period, even when considering construction material such as cement and nitrogen compounds. For most of the modelling cases, the estimated decrease in hydraulic conductivity over a period of ten years is less than 2% due to mineral precipitation. It was further concluded that it is more likely for fractures to clog (self-heal) than become open as a result of fracture mineral dissolution. With respect to the microbial evolution it was concluded that the potential for microbial iron hydroxide production will be large in all groundwater with ferrous iron. The potential for microbial calcite formation production will be large in all groundwater with high concentrations of Dissolved Organic Carbon (DOC) and methane, irrespective of oxygen, Eh (redox) or pH. The kinetics of the microbial evolution is not yet known, and microbes may then play a role in fracture clogging which could possibly be the factor that contributes to lower groundwater inflow to underground facilities with time, as shown for many facilities. The compilation of results from the relevant tests at underground laboratories in Canada, Japan, Sweden and Switzerland was focussed on the extent of the damage and its dependency on excavation methods and measurements of the hydraulic properties. The most important factor controlling the excavation damage is the choice of excavation method. Use of mechanical excavation may create irreversible damage less than 30 mm from the rock wall where increased micro-fracturing contributes to an increase in hydraulic conductivity. Several methods and sample scales have been used to characterise the damage zone. For a Tunnel Boring Machine < 5 mm of damage was recorded at Aespoe HRL and at Grimsel in Switzerland. The hydraulic conductivity was at e.g. Aespoe HRL determined to be in the range of 10-9 m/s over a distance of 1-2 mm from the tunnel

  20. Water quality analysis of groundwater in crystalline basement rocks, Northern Ghana

    Science.gov (United States)

    Anku, Y.S.; Banoeng-Yakubo, B.; Asiedu, D.K.; Yidana, S.M.

    2009-01-01

    Hydrochemical data are presented for groundwater samples, collected from fractured aquifers in parts of northern Ghana. The data was collected to assess the groundwater suitability for domestic and agricultural use. Results of the study reveal that the pH of the groundwater in the area is slightly acidic to slightly alkaline. The electrical conductivity values, total dissolved solids (TDS) values and calcium, magnesium and sodium concentrations in the groundwater are generally below the limit set by the WHO for potable water supply. On the basis of activity diagrams, groundwater from the fractured aquifers appears to be stable within the montmorillonite field, suggesting weathering of silicate minerals. An inverse distance weighting interpolator with a power of 2 was applied to the data points to produce prediction maps for nitrate and fluoride. The distribution maps show the presence of high nitrate concentrations (50-194??mg/l) in some of the boreholes in the western part of the study area indicating anthropogenic impact on the groundwater. Elevated fluoride level (1.5-4??mg/l), higher than the WHO allowable fluoride concentration of 1.5, is recorded in the groundwater underlying the northeastern part of the study area, more specifically Bongo and its surrounding communities of the Upper East region. Results of this study suggest that groundwater from the fractured aquifers in the area exhibit low sodicity-low salinity (S1-C1), low sodicity-medium salinity (S1-C2) characteristics [United States Salinity Laboratory (USSL) classification scheme]. All data points from this study plot within the 'Excellent to good' category on a Wilcox diagram. Groundwater in this area thus appears to provide irrigation water of excellent quality. The hydrochemical results indicate that, although nitrate and fluoride concentrations in some boreholes are high, the groundwater in the study area, based on the parameters analyzed, is chemically potable and suitable for domestic and

  1. A Sustainable Approach for Acid Rock Drainage Treatment using Clinoptilolite

    Science.gov (United States)

    Li, L. Y.; Xu, W.; Grace, J. R.

    2009-04-01

    Problems related to acid rock drainage (ARD) occur along many highways of British Columbia. The ARD problem at Pennask Creek along Highway 97C in the Thompson-Okanagan region is an ideal site for pilot study to investigate a possible remediation solution. The highway was opened in 1991. An ARD problem was identified in 1997. Both sides of Highway 97C are producing acidified runoff from both cut rock surface and a fractured ditch. This runoff eventually enters Pennask Creek, the largest spawning source of rainbow trout in British Columbia. The current remediation technique using limestone for ARD treatment appears to be unnecessarily expensive, to generate additional solid waste and to not be optimally effective. A soil mineral natural zeolite - clinoptilolite - which is inexpensive and locally available, has a high metal adsorption capacity and a significant buffering capacity. Moreover, the clinoptilolite materials could be back-flushed and reused on site. An earlier batch adsorption study from our laboratory demonstrated that clinoptilolite has a high adsorption capacity for Cu, Zn, Al, with adsorption concentrations 131, 158 and 215 mg/kg clinoptilolite, respectively, from ARD of pH 3.3. Removal of metals from the loaded clinoptilolite by back-flushing was found to depend on the pH, with an optimum pH range for extraction of 2.5 to 4.0 for a contact time of one hour. The rank of desorption effectiveness was EDTA > NaCl > NaNO3 > NaOAC > NaHCO3 > Na2CO3 > NaOH > Ca(OH)2. A novel process involving cyclic adsorption on clinoptilolite followed by regeneration of the sorbent by desorption is examined for the removal of heavy metals from acid rock drainage. Experimental results show that the adsorption of zinc and copper depends on the pH and on external mass transfer. Desorption is assisted by adding NaCl to the water. A slurry bubble column was able to significantly reduce the time required for both adsorption and desorption in batch tests. XRD analysis indicated

  2. Modeling of irradiated graphite (14)C transfer through engineered barriers of a generic geological repository in crystalline rocks.

    Science.gov (United States)

    Poskas, Povilas; Grigaliuniene, Dalia; Narkuniene, Asta; Kilda, Raimondas; Justinavicius, Darius

    2016-11-01

    There are two RBMK-1500 type graphite moderated reactors at the Ignalina nuclear power plant in Lithuania, and they are under decommissioning now. The graphite cannot be disposed of in a near surface repository, because of large amounts of (14)C. Therefore, disposal of the graphite in a geological repository is a reasonable solution. This study presents evaluation of the (14)C transfer by the groundwater pathway into the geosphere from the irradiated graphite in a generic geological repository in crystalline rocks and demonstration of the role of the different components of the engineered barrier system by performing local sensitivity analysis. The speciation of the released (14)C into organic and inorganic compounds as well as the most recent information on (14)C source term was taken into account. Two alternatives were considered in the analysis: disposal of graphite in containers with encapsulant and without it. It was evaluated that the maximal fractional flux of inorganic (14)C into the geosphere can vary from 10(-11)y(-1) (for non-encapsulated graphite) to 10(-12)y(-1) (for encapsulated graphite) while of organic (14)C it was about 10(-3)y(-1) of its inventory. Such difference demonstrates that investigations on the (14)C inventory and chemical form in which it is released are especially important. The parameter with the highest influence on the maximal flux into the geosphere for inorganic (14)C transfer was the sorption coefficient in the backfill and for organic (14)C transfer - the backfill hydraulic conductivity. PMID:27387810

  3. THERMAL DEGRADATION OF THERMOTROPIC LIQUID CRYSTALLINE TERPOLYESTERS BASED ON VANILLIC ACID, p-HYDROXYBENZOIC ACID AND POLY(ETHYLENE TEREPHTHALATE)

    Institute of Scientific and Technical Information of China (English)

    LI Xingui; HUANG Meirong; GUAN Guihe; SUN Tong

    1993-01-01

    Nine thermotropic liquid crystalline terpolyesters based on vanillic acid(V), p-hydroxybenzoic acid(H) and poly(ethylene terephthalate)(E) were investigated by thermogravimetry to ascertain their thermostability and the kinetic parameters for thermal degradation. Overall activation energy data of the degradation had been calculated over the range 5~70% weight loss. The temperatures and the activation energy of the degradation lie in the ranges of 384~394 ℃ at a heating rate of 1 ℃/min and 176~205 KJ/mol at the weight loss of 5%, respectively, which suggests that the terpolyesters have good thermostability.

  4. Plantain starch granules morphology, crystallinity, structure transition, and size evolution upon acid hydrolysis.

    Science.gov (United States)

    Hernández-Jaimes, C; Bello-Pérez, L A; Vernon-Carter, E J; Alvarez-Ramirez, J

    2013-06-01

    Plantain native starch was hydrolysed with sulphuric acid for twenty days. Hydrolysis kinetics was described by a logistic function, with a zero-order rate during the first seven days, followed by a slower kinetics dynamics at longer times. X-ray diffraction results revealed a that gradual increase in crystallinity occurred during the first seven days, followed by a decrease to values similar to those found in the native starch. Differential scanning calorimetry analysis suggested a sharp structure transition by the seventh day probably due to a molecular rearrangement of the starch blocklets and inhomogeneous erosion of the amorphous regions and semi crystalline lamellae. Scanning electron micrographs showed that starch granules morphology was continually degraded from an initial oval-like shape to irregular shapes due to aggregation effects. Granule size distribution broadened as hydrolysis time proceeded probably due to fragmentation and agglomeration phenomena of the hydrolysed starch granules.

  5. Poorly crystalline hydroxyapatite: A novel adsorbent for enhanced fulvic acid removal from aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Wei [Department of Environmental Science and Engineering, Nanjing Normal University, Nanjing 210023 (China); Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing Normal University, Nanjing 210023 (China); Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023 (China); Yang, Lei; Zhong, Wenhui; Cui, Jing [Department of Environmental Science and Engineering, Nanjing Normal University, Nanjing 210023 (China); Wei, Zhenggui, E-mail: weizhenggui@gmail.com [Department of Environmental Science and Engineering, Nanjing Normal University, Nanjing 210023 (China); Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing Normal University, Nanjing 210023 (China); Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023 (China)

    2015-03-30

    Graphical abstract: - Highlights: • Poorly crystalline HAP was firstly used for FA removal from aqueous solution. • The maximum adsorption capacity was determined to be 90.20 mg/g at 318 K. • Adsorption kinetics, isotherms and thermodynamic have been studied in detail. • Adsorption mechanism involved surface complexation, electrostatic interaction and hydrogen bonding. - Abstract: In this study, poorly crystalline hydroxyapatite (HAP) was developed as an efficient adsorbent for the removal of fulvic acid (FA) from aqueous solution. Surface functionality, crystallinity, and morphology of the synthetic adsorbent were studied by Fourier-transformation infrared (FT-IR) spectroscopy, powder X-ray diffraction (XRD) and transmission electron microscopy (TEM). The effects of various parameters such as crystallinity of adsorbent, contact time, adsorbent dosage, pH, initial adsorbate concentration, temperature, ionic strength and the presence of alkaline earth metal ions on FA adsorption were investigated. Results indicated that the nanosized HAP calcined at lower temperature was poorly crystalline (X{sub c} = 0.23) and had better adsorption capacity for FA than those (X{sub c} = 0.52, 0.86) calcined at higher temperature. FA removal was increased with increases of adsorbent dosage, temperature, ionic strength and the presence of alkali earth metal ions, but decreased as the pH increased. Kinetic studies showed that pseudo-second-order kinetic model better described the adsorption process. Equilibrium data were best described by Sips models, and the estimated maximum adsorption capacity of poorly crystalline HAP was 90.20 mg/g at 318 K, displaying higher efficiency for FA removal than previously reported adsorbents. FT-IR results revealed that FA adsorption over the adsorbent could be attributed to the surface complexation between the oxygen atom of functional groups of FA and calcium ions of HAP. Regeneration studies indicated that HAP could be recyclable for a long

  6. Synthesis of a nano-crystalline solid acid catalyst from fly ash and its catalytic performance

    Energy Technology Data Exchange (ETDEWEB)

    Chitralekha Khatri; Ashu Rani [Government P.G. College, Kota (India). Environmental Chemistry Laboratory

    2008-10-15

    The synthesis of nano-crystalline activated fly ash catalyst (AFAC) with crystallite size of 12 nm was carried out by chemical and thermal treatment of fly ash, a waste material generated from coal-burning power plants. Fly ash was chemically activated using sulfuric acid followed by thermal activation at 600{sup o}C. The variation of surface and physico-chemical properties of the fly ash by activation methods resulted in improved acidity and therefore, catalytic activity for acid catalyzed reactions. The AFAC was characterized by X-ray diffraction, FT-IR spectroscopy, N{sub 2}-adsorption-desorption isotherm, scanning electron microscopy, flame atomic absorption spectrophotometry and sulfur content by CHNS/O elemental analysis. It showed amorphous nature due to high silica content (81%) and possessed high BET surface area (120 m{sup 2}/g). The catalyst was found to be highly active solid acid catalyst for liquid phase esterification of salicylic acid with acetic anhydride and methanol giving acetylsalicylic acid and methyl salicylate respectively. A maximum yield of 97% with high purity of acetylsalicylic acid (aspirin) and a very high conversion 87% of salicylic acid to methyl salicylate (oil of wintergreen) was obtained with AFAC. The surface acidity and therefore, catalytic activity in AFAC was originated by increased silica content, hydroxyl content and higher surface area as compared to fly ash. The study shows that coal generated fly ash can be converted into potential solid acid catalyst for acid catalyzed reactions. Furthermore, this catalyst may replace conventional environmentally hazardous homogeneous liquid acids making an ecofriendly; solvent free, atom efficient, solid acid based catalytic process. 27 refs., 5 figs., 2 tabs.

  7. The absence of protein--sparing effects utilizing crystalline amino acids in stressed patients.

    Science.gov (United States)

    Ching, N; Mills, C J; Grossi, C; Angers, J W; Jham, G; Zurawinsky, H; Nealon, T F

    1979-11-01

    The protein-sparing effects of the peripheral infusion of crystalline amino acids (PAA) was studied metabolically in selected surgical patients subjected to various degrees of stress. Twenty-one patients (sixteen cancer patients receiving chemotherapy and/or radiotherapy, three with major abdominal traumatic injuries and four with paralytic ileus) were infused with 2 1/24 hours of a solution of 4.2% Travasol amino acids with only 5% glucose as a source of nonprotein calories. One-half of the cancer patients were also allowed ad libitum oral intake of a regular hospital diet or Vivonex-HN. The nutritional status was evaluated by measuring changes in body weight, serum albumin levels and nitrogen balance. Body weight decreased in only the trauma patients. When these solutions were the sole source of nutrients all patients were in negative nitrogen balance and had significant decreases in their serum albumin levels. Serum albumin levels were preserved only when extra sources of calories were provided. The infusion of the crystalline amino acids without adequate levels of nonprotein energy did not conserve protein in these stressed patients.

  8. Preparation of crystalline starch nanoparticles using cold acid hydrolysis and ultrasonication.

    Science.gov (United States)

    Kim, Hee-Young; Park, Dong June; Kim, Jong-Yea; Lim, Seung-Taik

    2013-10-15

    Waxy maize starch in an aqueous sulfuric acid solution (3.16 M, 14.7% solids) was hydrolyzed for 2-6 days, either isothermally at 40 °C or 4 °C, or at cycled temperatures of 4 and 40 °C (1 day each). The starch hydrolyzates were recovered as precipitates after centrifuging the dispersion (10,000 rpm, 10 min). The yield of starch hydrolyzates depended on the hydrolysis temperature and time, which varied from 6.8% to 78%. The starch hydrolyzed at 40 °C or 4/40 °C exhibited increased crystallinity determined by X-ray diffraction analysis, but melted in broader temperature range (from 60 °C to 110 °C). However, the starch hydrolyzed at 4 °C displayed the crystallinity and melting endotherm similar to those of native starch. The starch hydrolyzates recovered by centrifugation were re-dispersed in water (15% solids), and the dispersion was treated by an ultrasonic treatment (60% amplitude, 3min). The ultrasonication effectively fragmented the starch hydrolyzates to nanoparticles. The hydrolyzates obtained after 6 days of hydrolysis were more resistant to the ultrasonication than those after 2 or 4 days, regardless of hydrolysis temperatures. The starch nanoparticles could be prepared with high yield (78%) and crystallinity by 4 °C hydrolysis for 6 days followed by ultrasonication. Scanning electron microscopy revealed that the starch nanoparticles had globular shapes with diameters ranging from 50 to 90 nm.

  9. Crystalline and structural properties of acid-modified lotus rhizome C-type starch.

    Science.gov (United States)

    Cai, Jinwen; Cai, Canhui; Man, Jianmin; Yang, Yang; Zhang, Fengmin; Wei, Cunxu

    2014-02-15

    The crystalline and structural properties of acid-modified C-type starch from lotus rhizomes were investigated using a combination of techniques. The degradation of granule during hydrolysis began from the end distant from the hilum and then propagated into the center of granule, accompanied by loss of birefringence. The crystallinity changed from C-type to A-type via CA-type during hydrolysis. At the early stage of hydrolysis, the amylose content substantially reduced, the peak and conclusion gelatinization temperatures increased, and the enthalpy decreased. During hydrolysis, the double helix content gradually increased and the amorphous component decreased, the lamellar peak intensity firstly increased and then decreased accompanied by hydrolysis of amorphous and crystalline regions. This study elucidated that B-type allomorph was mainly arranged in the distal region of eccentric hilum, A-type allomorph was mainly located in the periphery of hilum end, and the center of granule was a mixed distribution of A- and B-type allomorphs.

  10. Quality of water from crystalline rock aquifers in New England, New Jersey, and New York, 1995-2007

    Science.gov (United States)

    Flanagan, Sarah M.; Ayotte, Joseph D.; Robinson,, Gilpin R.

    2012-01-01

    Crystalline bedrock aquifers in New England and parts of New Jersey and New York (NECR aquifers) are a major source of drinking water. Because the quality of water in these aquifers is highly variable, the U.S. Geological Survey (USGS) statistically analyzed chemical data on samples of untreated groundwater collected from 117 domestic bedrock wells in New England, New York, and New Jersey, and from 4,775 public-supply bedrock wells in New England to characterize the quality of the groundwater. The domestic-well data were from samples collected by the USGS National Water-Quality Assessment (NAWQA) Program from 1995 through 2007. The public-supply-well data were from samples collected for the U.S. Environmental Protection Agency (USEPA) Safe Drinking Water Act (SDWA) Program from 1997 through 2007. Chemical data compiled from the domestic wells include pH, specific conductance, dissolved oxygen, alkalinity, and turbidity; 6 nitrogen and phosphorus compounds, 14 major ions, 23 trace elements, 222radon gas (radon), 48 pesticide compounds, and 82 volatile organic compounds (VOCs). Additional samples were collected from the domestic wells for the analysis of gross alpha- and gross beta-particle radioactivity, radium isotopes, chlorofluorocarbon isotopes, and the dissolved gases methane, carbon dioxide, nitrogen, and argon. Chemical data compiled from the public-supply wells include pH, specific conductance, nitrate, iron, manganese, sodium, chloride, fluoride, arsenic, uranium, radon, combined radium (226radium plus 228radium), gross alpha-particle radioactivity, and methyl tert-butyl ether (MtBE). Patterns in fluoride, arsenic, uranium, and radon distributions were discernable when the data were compared to lithology groupings of the bedrock, indicating that the type of bedrock has an effect on the quality of groundwater from NECR aquifers. Fluoride concentrations were significantly higher in groundwater samples from the alkali granite, peraluminous granite, and

  11. Use of the Fracture Continuum Model for Numerical Modeling of Flow and Transport of Deep Geologic Disposal of Nuclear Waste in Crystalline Rock

    Science.gov (United States)

    Hadgu, T.; Kalinina, E.; Klise, K. A.; Wang, Y.

    2015-12-01

    Numerical modeling of disposal of nuclear waste in a deep geologic repository in fractured crystalline rock requires robust characterization of fractures. Various methods for fracture representation in granitic rocks exist. In this study we used the fracture continuum model (FCM) to characterize fractured rock for use in the simulation of flow and transport in the far field of a generic nuclear waste repository located at 500 m depth. The FCM approach is a stochastic method that maps the permeability of discrete fractures onto a regular grid. The method generates permeability fields using field observations of fracture sets. The original method described in McKenna and Reeves (2005) was designed for vertical fractures. The method has since then been extended to incorporate fully three-dimensional representations of anisotropic permeability, multiple independent fracture sets, and arbitrary fracture dips and orientations, and spatial correlation (Kalinina et al. 20012, 2014). For this study the numerical code PFLOTRAN (Lichtner et al., 2015) has been used to model flow and transport. PFLOTRAN solves a system of generally nonlinear partial differential equations describing multiphase, multicomponent and multiscale reactive flow and transport in porous materials. The code is designed to run on massively parallel computing architectures as well as workstations and laptops (e.g. Hammond et al., 2011). Benchmark tests were conducted to simulate flow and transport in a specified model domain. Distributions of fracture parameters were used to generate a selected number of realizations. For each realization, the FCM method was used to generate a permeability field of the fractured rock. The PFLOTRAN code was then used to simulate flow and transport in the domain. Simulation results and analysis are presented. The results indicate that the FCM approach is a viable method to model fractured crystalline rocks. The FCM is a computationally efficient way to generate realistic

  12. CHOLESTERIC LIQUID CRYSTALLINE CHARACTER ON THE SURFACE OF CHITOSAN/POLYACRYLIC ACID COMPOSITES

    Institute of Scientific and Technical Information of China (English)

    Yan-ming Dong; Yu-song; Wu Mian Wang

    2001-01-01

    The cholesteric liquid crystalline structure in chitosan/polyacrylic acid composite films was studied by surface techniques. A periodical lamellar-like structure was observed in the permanganic acid etched film surface by both scanning electron microscopy (SEM) and atomic force microscopy (AFM), instead of the thumb-print texture which can be detected with polarized optical microscopy. It is suggested that the periodical lamellar-like structure is induced by the etching selectivity between cholesteric layers due to different molecular arrangement on the film surface. Four kinds of perpendicular disclinations, I.e. Χ→τ- + λ+, χ→λ- + τ+, χ→τ- + τ+ and χ→λ- + λ+, were found in the composite films from SEM observations. The smallest periodicity of lamellar-like structure (equals to halfpitch) is 20~40 nm measured with AFM.

  13. Predictive permeability model of extensional faults in crystalline and metamorphic rocks; verification by pre-grouting in two sub-sea tunnels, Norway

    Science.gov (United States)

    Ganerød, Guri Venvik; Braathen, Alvar; Willemoes-Wissing, Bjørn

    2008-08-01

    This paper link quantitative fault zone descriptions, qualitative fracture and fault rock properties, and engineering data in the study of the permeability structure of fault zones. Datasets include scan-lines, drill cores and cement pre-grouting from two sub-sea tunnels in gneissic and granitic rocks, from which systematic pre-grouting volumes can be used to analyse the in-site relative permeability both in host rocks and fault zones. Major extensional faults intersected by the tunnels reveal common fault rocks surrounding intensively fractured rock lenses in the core. Fracture frequencies in these lenses can reach 100 fractures/metre (f/m). In the bounding damage zones, networks of fracture sets make up an inner zone of fairly high frequency (20-30 f/m) of fault-parallel, long fractures connected by shorter fractures. An outer zone has lower frequencies (rock volume into sub-zones characterized by distinct structural style and permeability, with a background level and three fault related sub-zones (fault core, inner damage zone, and outer damage zone). Injection data shows that the background sub-zone commonly can be injected with less than 0.05 m 3 cement per metre tunnel (commonly not injected), whereas the fault core has permeability characteristics nearly as low as the outer damage zone, represented by 0.1-0.2 m 3 cement per metre tunnel, with occasional peaks towards 0.5 m 3. The maximum of cement injection lies in the inner damage zone, marginal to the fault core, with 0.3-0.7 m 3 cement per metre tunnel, locally exceeding 1 m 3. This gives a relative relationship for cement injection of approximately 1:2:1 between fault core, inner damage zone, and outer damage zone of extensional fault zones in crystalline and metamorphic rocks.

  14. Mixing-controlled uncertainty in long-term predictions of acid rock drainage from heterogeneous waste-rock piles

    Science.gov (United States)

    Pedretti, D.; Beckie, R. D.; Mayer, K. U.

    2015-12-01

    The chemistry of drainage from waste-rock piles at mine sites is difficult to predict because of a number of uncertainties including heterogeneous reactive mineral content, distribution of minerals, weathering rates and physical flow properties. In this presentation, we examine the effects of mixing on drainage chemistry over timescales of 100s of years. We use a 1-D streamtube conceptualization of flow in waste rocks and multicomponent reactive transport modeling. We simplify the reactive system to consist of acid-producing sulfide minerals and acid-neutralizing carbonate minerals and secondary sulfate and iron oxide minerals. We create multiple realizations of waste-rock piles with distinct distributions of reactive minerals along each flow path and examine the uncertainty of drainage geochemistry through time. The limited mixing of streamtubes that is characteristic of the vertical unsaturated flow in many waste-rock piles, allows individual flowpaths to sustain acid or neutral conditions to the base of the pile, where the streamtubes mix. Consequently, mixing and the acidity/alkalinity balance of the streamtube waters, and not the overall acid- and base-producing mineral contents, control the instantaneous discharge chemistry. Our results show that the limited mixing implied by preferential flow and the heterogeneous distribution of mineral contents lead to large uncertainty in drainage chemistry over short and medium time scales. However, over longer timescales when one of either the acid-producing or neutralizing primary phases is depleted, the drainage chemistry becomes less controlled by mixing and in turn less uncertain. A correct understanding of the temporal variability of uncertainty is key to make informed long-term decisions in mining settings regarding the management of waste material.

  15. Deep Groundwater Circulation within Crystalline Basement Rocks and the Role of Hydrologic Windows in the Formation of the Truth or Consequences, New Mexico Low-Temperature Geothermal System

    Science.gov (United States)

    Pepin, J.; Person, M. A.; Phillips, F. M.; Kelley, S.; Timmons, S.; Owens, L.; Witcher, J. C.; Gable, C. W.

    2014-12-01

    Hot Springs are common in amagmatic settings, but the mechanisms of heating are often obscure. We have investigated the origin of the Truth or Consequences, New Mexico low-temperature (~ 41 °C) hot springs in the southern Rio Grande rift. We tested two mechanisms that could account for the geothermal anomaly. The first scenario is that the anomaly is the result of lateral forced convection associated with a gently-dipping carbonate aquifer. The second scenario is that high permeability of crystalline basement rocks permits circulation of groundwater down to depths of 8 km prior to discharging in Truth or Consequences. To test these hypotheses, we constructed a two-dimensional hydrothermal model of the region using FEMOC. Model parameters were constrained by calibrating to measured temperatures, specific discharge rates and groundwater residence times. We collected 16 temperature profiles, 11 geochemistry samples and 6 carbon-14 samples within the study area. The geothermal waters are Na+/Cl- dominated and have apparent groundwater ages ranging from 5,500 to 11,500 years. Hot Springs geochemistry is consistent with water/rock interaction in a silicate geothermal reservoir, rather than a carbonate system. Peclet-number analysis of temperature profiles suggests specific discharge rates beneath Truth or Consequences range from 2 to 4 m/year. Geothermometry indicates maximum reservoir temperatures are around 167 °C. We were able to reasonably reproduce observed measurements using the permeable-basement scenario (10-12 m2). The carbonate-aquifer scenario failed to match observations. Our findings imply that the Truth or Consequences geothermal system formed as a result of deep groundwater circulation within permeable crystalline basement rocks. Focused geothermal discharge is the result of localized faulting, which has created a hydrologic window through a regional confining unit. In tectonically active areas, deep groundwater circulation within fractured crystalline

  16. Rock Glacier Outflows May Adversely Affect Lakes: Lessons from the Past and Present of Two Neighboring Water Bodies in a Crystalline-Rock Watershed

    OpenAIRE

    Ilyashuk, Boris P.; Ilyashuk, Elena A.; Psenner, Roland; Tessadri, Richard; Koinig, Karin A.

    2014-01-01

    Despite the fact that rock glaciers are one of the most common geomorphological expressions of mountain permafrost, the impacts of their solute fluxes on lakes still remain largely obscure. We examined water and sediment chemistry, and biota of two neighboring water bodies with and without a rock glacier in their catchments in the European Alps. Paleolimnological techniques were applied to track long-term temporal trends in the ecotoxicological state of the water bodies and to establish their...

  17. Development of grout injection model for geological disposal of high level nuclear waste. 2. Hydrogeological descriptive modeling by discrete fracture network in crystalline rock test site

    International Nuclear Information System (INIS)

    This study aims to establish grouting techniques and evaluation of the effects of grouting in the geological environment of crystalline rock. A hydrogeological model has been generated using discrete fracture networks (DFN) based on the data obtained by the short-borehole investigation campaign performed at Grimsel test site in Switzerland to support the design of planned in-situ grouting test. The equivalent porous media with the consideration of hydraulic heterogeneity has been created from the DFN in order to be provided for the simulation of the grout injection process. Uncertainties and remaining issues associated with the assumption in interpreting the data and its modeling were addressed in a systematic way. (author)

  18. The occurrence of fatty acids in immature source rocks and their distribution characteris-tics

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The fatty acids in extractable bitumen and kerogen of immature source rocks of the Liaohe Basin and Jiyang sag were investigated in this study. The result showed that the bitumen fatty acids were mainly associated with non-hydrocarbon fraction and that the kerogen fatty acids with some tightly bound fatty acids were mainly bounded in a net structure of kerogen by ester bonds. For the investigated source rocks, the fatty acids in bitumen, bound fatty acids and tightly bound acids in kerogen ranged in 0.01% -0.073 9%, 0.005% - 0.045 5% and 0.005%- 0.010% respectively. Among the fatty acids analyzed in this study, mono-carboxylic acids, a, w-di-carboxylic acids and hydroxy acids accounted for 70%-100%, 0%-30% and <10% respec-tively. It was also found that the mono-carboxylic acids with longer chains mainly existed in bitumen, and that the a, w-di-carboxylic acids and hydroxy acids mainly existed in kerogen. From above, it was assumed that the mono-car- boxylic acids in bitumen might have played an important role in the hydrocarbon generation from fatty acids in imma-ture source rocks.

  19. Operational Lessons Learned During Bioreactor Demonstrations for Acid Rock Drainage Treatment

    Science.gov (United States)

    The U.S. Environmental Protection Agency’s Mine Waste Technology Program (MWTP) has emphasized the development of biologically-based treatment technologies for acid rock drainage (ARD). Progressively evolving technology demonstrations have resulted in significant advances in sul...

  20. Operational Lessons Leaned During bioreactor Demonstrations for Acid Rock Drainage Treatment

    Science.gov (United States)

    The U.S. Environmental Protection Agency's Mine Waste Technology Program (MWTP) has emphasized the development of biologically-based treatment technologies for acid rock drainage (ARD). Progressively evolving technology demonstrations have resulted in significant advances in sulf...

  1. Tailoring the morphology and crystallinity of poly(L-lactide acid) electrospun membranes

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Clarisse; Sencadas, Vitor; Costa, Carlos Miguel; Lanceros-Mendez, Senentxu [Centro/Departamento de Fisica da Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal); Gomez Ribelles, Jose Luis, E-mail: lanceros@fisica.uminho.pt [Centro de Biomateriales e Ingenieria Tisular, Universidad Politecnica de Valencia, 46022 Valencia (Spain)

    2011-02-15

    Biodegradable poly(L-lactic acid) (PLLA) microfibers were prepared by electrospinning by varying the applied potential, solution flow rate and collector conditions. PLLA fibers with smoothly oriented and random morphologies were obtained and characterized by scanning electron microscopy. The optimum fiber orientation was obtained at 1000 rpm using a 20.3 cm diameter collecting drum, while for higher and lower drum rotation speeds, the rapid random motion of the jets resulted in a random fiber distribution. The deformation of the jet with rapid solidification during electrospinning often results in a metastable phase. PLLA electrospun fibers are amorphous but contain numerous crystal nuclei that rapidly grow when the sample is heated to 70-140 {sup 0}C. In this way, the degree of crystallinity of the fibers can be tailored between 0 and 50% by annealing. Infrared transmission spectra revealed that the processing conditions do not affect the PLLA samples at the molecular level and that the crystallinity of the samples is related to the presence of {alpha}-crystals.

  2. Investigation on crystalline perfection, mechanical, piezoelectric and ferroelectric properties of L-tartaric acid single crystal

    Energy Technology Data Exchange (ETDEWEB)

    Murugan, G. Senthil, E-mail: nanosen@gmail.com; Ramasamy, P., E-mail: nanosen@gmail.com [Centre for Crystal Growth, SSN College of Engineering, Kalavakkam, Tamilnadu - 603110 (India)

    2014-04-24

    Polar organic nonlinear optical material, L-tartaric acid single crystals have been grown from slow evaporation solution growth technique. Single crystal X-ray diffraction study indicates that the grown crystal crystallized in monoclinic system with space group P2{sub 1}. Crystalline perfection of the crystal has been evaluated by high resolution X-ray diffraction technique and it reveals that the crystal quality is good and free from structural grain boundaries. Mechanical stability of the crystal has been analyzed by Vickers microhardness measurement and it exhibits reverse indentation size effect. Piezoelectric d{sub 33} co-efficient for the crystal has been examined and its value is 47 pC/N. The ferroelectric behaviour of the crystal was analyzed by polarization-electric field hysteresis loop measurement.

  3. LIQUID CRYSTALLINE BEHAVIOR OF HYDROXYPROPYL CELLULOSE ESTERIFIED WITH 4-ALKOXYBENZOIC ACID.

    Directory of Open Access Journals (Sweden)

    Yehia Fahmy

    2010-07-01

    Full Text Available A series of 4- alkyoxybenzoyloxypropyl cellulose (ABPC-n samples was synthesized via the esterification of hydroxypropyl cellulose (HPC with 4-alkoxybenzoic acid bearing different numbers of carbon atoms. The molecular structure of the ABPC-n was confirmed by Fourier transform infrared (FT-IR spectroscopy and 1H NMR spectroscopy. The liquid crystalline (LC phases and transitions behaviors were investigated using differential scanning calorimetry (DSC, polarized light microscopy (PLM, and refractometry. It was found that the glass transition (Tg and clearing (Tc temperatures decrease with increase of the alkoxy chain length. It was observed that the derivatives with an odd number of carbon atoms are non-mesomorphic. This series of ABPC-n polymers exhibit characteristic features of cholesteric LC phases between their glass transition and isotropization temperatures.

  4. Synergic effect of tungstophosphoric acid and sonication for rapid synthesis of crystalline nanocellulose.

    Science.gov (United States)

    Hamid, Sharifah Bee Abd; Zain, Siti Khadijah; Das, Rasel; Centi, Gabriele

    2016-03-15

    The utilization of sonication in combination with tungstophosphoric acid (PWA) catalyst reduces dramatically the time of operations from 30h to 10min by using an optimum sonication power of 225W. The basic cellulosic structure is maintained, allowing preparing high-quality nanocellulose. The size of the nanocellulose obtained was in the range from 15 to 35nm in diameter and several hundred nanometers in length, with a high crystallinity of about 88%. The nanocellulose shows a surface charge of -38.2mV which allows to obtaina stable colloidal suspension. The surface tension of the stable, swollen aqueous nanocellulose was close to that of water. These characteristics, together with the fast procedure allowed from the synergic combination of PWA and sonication, evidence the high potential of the proposed method for the industrial production of nanocellulose having the properties required in many applications. PMID:26794771

  5. Simulation experiments for evolution of fatty acids in immature source rocks

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The anhydrous, hydrous and bitumen-extrac- ted simulations were carried out for the immature source rocks from the Liaohe sag. It has been shown from the result that with increasing temperature in simulation experiments, the fatty acids content decreased at first and then increased. The decrease of fatty acids in immature rocks is presumably related to alkanes generation in immature oils, whilst the increase may be related to the fact that some additional fatty acids are generated from kerogen and the tightly bound fatty acids in kerogen are released as bound fatty acids in kerogen and unbound fatty acids in bitumen. The fact that the bitumen generated from kerogen contains fatty acids has demonstrated that some bound and tightly bound fatty acids in kerogen can be transferred into bitumen. The preferential fatty acids in the immature source rocks are found to be mono-carboxylic acids with longer chains, whilst krogen contains relatively more di-carboxylic acids. It has been found that the fatty acids in immature source rocks can be changed from that with more longer chains to that with more shorter chains when evolution extent has been increased. Based on simulation results and the fact that the majority of fatty acids in immature oils are those with longer chains, it is inferred that the contribution of fatty acids to forming alkanes in immature oils mainly takes place at the evolution stage with R0 (0.6%. The simulation experiments have also demonstrated that H2O could promote the generation of fatty acids with more di-carboxylic acids and delay alkanes formation from fatty acids.

  6. Assessing amino acid racemization variability in coral intra-crystalline protein for geochronological applications

    Science.gov (United States)

    Hendy, Erica J.; Tomiak, Peter J.; Collins, Matthew J.; Hellstrom, John; Tudhope, Alexander W.; Lough, Janice M.; Penkman, Kirsty E. H.

    2012-06-01

    Over 500 Free Amino Acid (FAA) and corresponding Total Hydrolysed Amino Acid (THAA) analyses were completed from eight independently-dated, multi-century coral cores of massive Porites sp. colonies. This dataset allows us to re-evaluate the application of amino acid racemization (AAR) for dating late Holocene coral material, 20 years after Goodfriend et al. (GCA56 (1992), 3847) first showed AAR had promise for developing chronologies in coral cores. This re-assessment incorporates recent method improvements, including measurement by RP-HPLC, new quality control approaches (e.g. sampling and sub-sampling protocols, statistically-based data screening criteria), and cleaning steps to isolate the intra-crystalline skeletal protein. We show that the removal of the extra-crystalline contaminants and matrix protein is the most critical step for reproducible results and recommend a protocol of bleaching samples in NaOCl for 48 h to maximise removal of open system proteins while minimising the induced racemization. We demonstrate that AAR follows closed system behaviour in the intra-crystalline fraction of the coral skeletal proteins. Our study is the first to assess the natural variability in intra-crystalline AAR between colonies, and we use coral cores taken from the Great Barrier Reef, Australia, and Jarvis Island in the equatorial Pacific to explore variability associated with different environmental conditions and thermal histories. Chronologies were developed from THAA Asx D/L, Ala D/L, Glx D/L and FAA Asx D/L for each core and least squares Monte Carlo modelling applied in order to quantify uncertainty of AAR age determinations and assess the level of dating resolution possible over the last 5 centuries. AAR within colonies follow consistent stratigraphic aging. However, there are systematic differences in rates between the colonies, which would preclude direct comparison from one colony to another for accurate age estimation. When AAR age models are developed from

  7. Estimation of groundwater flow directions and the tensor of hydraulic conductivity in crystalline massif rocks using information from surface structural geology and mining exploration boreholes

    Science.gov (United States)

    Florez, C.; Romero, M. A.; Ramirez, M. I.; Monsalve, G.

    2013-05-01

    In the elaboration of a hydrogeological conceptual model in regions of mining exploration where there is significant presence of crystalline massif rocks., the influence of physical and geometrical properties of rock discontinuities must be evaluated. We present the results of a structural analysis of rock discontinuities in a region of the Central Cordillera of Colombia (The upper and middle Bermellon Basin) in order to establish its hydrogeological characteristics for the improvement of the conceptual hydrogeological model for the region. The geology of the study area consists of schists with quartz and mica and porphyritic rocks, in a region of high slopes with a nearly 10 m thick weathered layer. The main objective of this research is to infer the preferential flow directions of groundwater and to estimate the tensor of potential hydraulic conductivity by using surface information and avoiding the use of wells and packer tests. The first step of our methodology is an analysis of drainage directions to detect patterns of structural controls in the run-off; after a field campaign of structural data recollection, where we compile information of strike, dip, continuity, spacing, roughness, aperture and frequency, we built equal area hydro-structural polar diagrams that indicate the potential directions for groundwater flow. These results are confronted with records of Rock Quality Designation (RQD) that have been systematically taken from several mining exploration boreholes in the area of study. By using all this information we estimate the potential tensor of hydraulic conductivity from a cubic law, obtaining the three principal directions with conductivities of the order of 10-5 and 10-6 m/s; the more conductive joint family has a NE strike with a nearly vertical dip.

  8. Physical Matrix Characterisation: Studies of Crystalline Rocks and Consolidated Clays by PMMA Method and Electron Microscopy as Support of Diffusion Analyses

    Energy Technology Data Exchange (ETDEWEB)

    Siitari-Kauppi, M.; Leskinen, A.; Kelokaski, A.; Togneri, L.; Alonso, U.; Missana, T.; Garcia-Gutierrez, M.; Patelli, A.

    2007-07-01

    Crystalline rock and consolidated clay are both considered adequate host rocks for a high-level radioactive waste deep geological repository (HLWR). Over the extended periods of HLWR operation, long-lived radionuclides (RN) may be released from the fuel and migrate to the geo/biosphere. To predict the fate of contaminants and to assess the safety of the host rock, it is very important to determine transport parameters, as diffusion coefficients, and to relate them to the physical properties of the barriers, as connected porosity. In heterogeneous materials, it is also a major task to describe the transport at the mineral scale evaluating diffusion coefficients and mineral-specific porosities on single minerals. The main objective of this study was to determine within granite and consolidated clay, the connective porosity and mineral-specific porosities by poly-methylmethacrylate (PMMA) autoradiography method. Scanning electron microscopy and energy-dispersive X-ray analyses (FESEM/EDS) were performed in order to study the pore apertures of porous regions in greater detail and to identify the corresponding minerals. By the novel application of the nuclear ion beam technique Rutherford Backscattering Spectrometry (RBS) apparent diffusion coefficients were determined at mineral scale. Finally, the porosity results were used to evaluate the effective diffusion coefficients and retention parameters of single minerals in different granite samples and consolidated clays. (Author) 42 refs.

  9. Tea Flavanols Block Advanced Glycation of Lens Crystallins Induced by Dehydroascorbic Acid.

    Science.gov (United States)

    Zhu, Yingdong; Zhao, Yantao; Wang, Pei; Ahmedna, Mohamed; Ho, Chi-Tang; Sang, Shengmin

    2015-01-20

    Growing evidence has shown that ascorbic acid (ASA) can contribute to protein glycation and the formation of advanced glycation end products (AGEs), especially in the lens. The mechanism by which ascorbic acid can cause protein glycation probably originates from its oxidized form, dehydroascorbic acid (DASA), which is a reactive dicarbonyl species. In the present study, we demonstrated for the first time that four tea flavanols, (-)-epigallocatechin 3-O-gallate (EGCG), (-)-epigallocatechin (EGC), (-)-epicatechin 3-O-gallate (ECG), and (-)-epicatechin (EC), could significantly trap DASA and consequently form 6C- or 8C-ascorbyl conjugates. Among these four flavanols, EGCG exerted the strongest trapping efficacy by capturing approximate 80% of DASA within 60 min. We successfully purified and identified seven 6C- or 8C-ascorbyl conjugates of flavanols from the chemical reaction between tea flavanols and DASA under slightly basic conditions. Of which, five ascorbyl conjugates, EGCGDASA-2, EGCDASA-2, ECGDASA-1, ECGDASA-2 and ECDASA-1, were recognized as novel compounds. The NMR data showed that positions 6 and 8 of the ring A of flavanols were the major active sites for trapping DASA. We further demonstrated that tea flavanols could effectively inhibit the formation of DASA-induced AGEs via trapping DASA in the bovine lens crystallin-DASA assay. In this assay, 8C-ascorbyl conjugates of flavanols were detected as the major adducts using LC-MS. This study suggests that daily consumption of beverages containing tea flavanols may prevent protein glycation in the lens induced by ascorbic acid and its oxidized products. PMID:25437149

  10. Use of the {sup 14}C-PMMA and He-gas methods to characterise excavation disturbance in crystalline rock

    Energy Technology Data Exchange (ETDEWEB)

    Autio, J.; Kirkkomaeki, T. [Saanio and Riekkola Oy, Helsinki (Finland); Siitari-Kauppi, M. [University of Helsinki (Finland). Lab. of Radiochemistry; Timonen, J.; Laajalahti, M.; Aaltonen, T.; Maaranen, J. [University of Jyvaeskylae (Finland). Dept. of Physics

    1999-04-01

    Characterisation of the excavation disturbance caused by boring of experimental full-scale deposition holes in the Research Tunnel at Olkiluoto was carried out successfully by using two novel methods; the {sup 14}C-PMMA and He-gas methods, which were modified and applied for the first time in this type of study. The experience obtained implies that the techniques are feasible and can be used to study similar types of rock excavation disturbance such as that caused by boring with mini discs, a technique which will be used in the underground Hard Rock Laboratory at Aespoe during late 1998 and early 1999. Both of the measurement methods have been in continuous use and the work has included development of both the measuring and interpretation techniques. Use of the {sup 14}C-PMMA method is suggested for studies of rock structure and the spatial distribution of porosity. The {sup 14}C-PMMA method also provides quantitative information about nanometer-range porosity which is beyond the scope of most standard methods of microscopic investigation. The use of He-gas methods are proposed for determining the diffusion coefficient, permeability and complementary porosity of rock samples taken from the disturbed zone. (orig.) 23 refs.

  11. Paleoproterozoic mojaveprovince in northwestern Mexico? Isotopic and U-Pb zircon geochronologic studies of precambrian and Cambrian crystalline and sedimentary rocks, Caborca, Sonora

    Science.gov (United States)

    Lang, Farmer G.; Bowring, S.A.; Matzel, J.; Maldonado, G.E.; Fedo, C.; Wooden, J.

    2005-01-01

    Whole-rock Nd isotopic data and U-Pb zircon geochronology from Precambrian crystalline rocks in the Caborca area, northern Sonora, reveal that these rocks are most likely a segment of the Paleoproterozoic Mojave province. Supporting this conclusion are the observations that paragneiss from the ??? 1.75 Ga Bamori Complex has a 2.4 Ga Nd model age and contains detrital zircons ranging in age from Paleo- proterozoic (1.75 Ga) to Archean (3.2 Ga). Paragneisses with similar age and isotopic characteristics occur in the Mojave province in southern California. In addition, "A-type" granite exposed at the southern end of Cerro Rajon has ca 2.0 Ga Nd model age and a U-Pb zircon age of 1.71 Ga, which are similar to those of Paleoproterozoic granites in the Mojave province. Unlike the U.S. Mojave province, the Caborcan crust contains ca. 1.1 Ga granite (Aibo Granite), which our new Nd isotopic data suggest is largely the product of anatexis of the local Precambrian basement. Detrital zircons from Neoproterozoic to early Cambrian miogeoclinal arenites at Caborca show dominant populations ca. 1.7 Ga, ca. 1.4 Ga, and ca. 1.1 Ga, with subordinate Early Cambrian and Archean zircons. These zircons were likely derived predominately from North American crust to the east and northeast, and not from the underlying Caborcan basement. The general age and isotopic similarities between Mojave province basement and overlying miogeoclinal sedimentary rocks in Sonora and southern California is necessary, but not sufficient, proof of the hypothesis that Sonoran crust is allochthonous and was transported to its current position during the Mesozoic along the proposed Mojave-Sonora megashear. One viable alternative model is that the Caborcan Precambrian crust is an isolated, autochthonous segment of Mojave province crust that shares a similar, but not identical, Proterozoic geological history with Mojave province crust found in the southwest United States ?? 2005 Geological Society of America.

  12. Preparation of Highly Crystalline TiO2 Nanostructures by Acid-assisted Hydrothermal Treatment of Hexagonal-structured Nanocrystalline Titania/Cetyltrimethyammonium Bromide Nanoskeleton

    Directory of Open Access Journals (Sweden)

    Sakai Hideki

    2010-01-01

    Full Text Available Abstract Highly crystalline TiO2 nanostructures were prepared through a facile inorganic acid-assisted hydrothermal treatment of hexagonal-structured assemblies of nanocrystalline titiania templated by cetyltrimethylammonium bromide (Hex-ncTiO2/CTAB Nanoskeleton as starting materials. All samples were characterized by X-ray diffraction (XRD and transmission electron microscopy (TEM. The influence of hydrochloric acid concentration on the morphology, crystalline and the formation of the nanostructures were investigated. We found that the morphology and crystalline phase strongly depended on the hydrochloric acid concentrations. More importantly, crystalline phase was closely related to the morphology of TiO2 nanostructure. Nanoparticles were polycrystalline anatase phase, and aligned nanorods were single crystalline rutile phase. Possible formation mechanisms of TiO2 nanostructures with various crystalline phases and morphologies were proposed.

  13. Microbial exoenzymes as bioindicators of acid rock drainage impacts in the Finniss River

    International Nuclear Information System (INIS)

    Sediment samples were collected from several sites along the East Branch of the Finniss River during the dry season (June, 1999), when the East Branch is drying into a series of ponds. The sites included those upstream from the Rum Jungle mine site (EB8A, EB8B, FCA, FCB), a site receiving acid leachate from the waste rock (WO), sites downstream from the mine that are impacted by acid and metal contamination (EB6, TCP, EB5D, EB4U, EB2) and reference sites not subject to acid rock drainage (HS, EB4S, LFRB). Exoenzyme activities were measured with a spectrofluorometric technique that involved measuring the increase in fluorescence when an artificial fluorogenic substrate (that mimics the natural substrate) is hydrolysed to a highly fluorescent product. The present findings indicate that the acid rock drainage impacted sediments contain acidophilic, heterotrophic microorganisms, bacteria and/or fungi, producing extracellular enzymes adapted to the acid conditions. This study has demonstrated that measurements of extracellular enzyme activities in river sediments provide a rapid, sensitive technique for determining microbial activity and productivity. In aquatic ecosystems some exoenzymes, particularly leucine-aminopeptidase, could be used as bioindicators of pollution from acid rock drainage

  14. A verapamil electrochemical sensor based on magnetic mobile crystalline material-41 grafted by sulfonic acid

    International Nuclear Information System (INIS)

    Graphical abstract: The Fe2O3-MCM-41-SO3H was characterized with TEM and used to investigate the electrochemical behavior of verapamil. The results indicated that Fe2O3-MCM-41-SO3H-CPE facilitate the determination of verapamil with good sensitivity. Highlights: ► Electrooxidation of verapamil was performed using Fe2O3-MCM-41-SO3H-CPE. ► Modified electrode shows many advantages as a verapamil sensor. ► Excellent electrocatalytic activity was obtained for verapamil oxidation. ► The response of the modified electrode is linear over the entire 50–160 and 160–350 nM. -- Abstract: Magnetic (Fe2O3) mobile crystalline material-41 (MCM-41) grafted by sulfonic acid (Fe2O3-MCM-41-SO3H) was prepared and characterized using transmission electron microscopy (TEM) and nitrogen adsorption–desorption techniques. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) and square wave voltametry (SQWV) used to investigate the electrochemical behavior of verapamil at the sulfonic acid functionalized magnetic mesoporous silica, which was modified through carbon paste electrode (Fe2O3-MCM-41-SO3H-CPE). The Fe2O3-MCM-41-SO3H-CPE showed better performance for the electrochemical oxidation of verapamil, when compared with bare carbon paste electrode (CPE) and Fe2O3-MCM-41-CPE. The experimental conditions influencing the determination of verapamil were optimized and under optimal conditions, the oxidation peak current was proportional to verapamil concentration in the range of 50–160 and 160–350 nmol dm−3, while the detection limit was 41 nmol dm−3 (S/N = 3). The proposed method was successfully applied to determine verapamil in human serum, yielding satisfactory results. The spiked recoveries were in the range of (94.5–104.1%)

  15. Conceptual models of the formation of acid-rock drainage at road cuts in Tennessee

    Science.gov (United States)

    Bradley, Michael W.; Worland, Scott; Byl, Tom

    2015-01-01

    Pyrite and other minerals containing sulfur and trace metals occur in several rock formations throughout Middle and East Tennessee. Pyrite (FeS2) weathers in the presence of oxygen and water to form iron hydroxides and sulfuric acid. The weathering and interaction of the acid on the rocks and other minerals at road cuts can result in drainage with low pH (< 4) and high concentrations of trace metals. Acid-rock drainage can cause environmental problems and damage transportation infrastructure. The formation and remediation of acid-drainage from roads cuts has not been researched as thoroughly as acid-mine drainage. The U.S Geological Survey, in cooperation with the Tennessee Department of Transportation, is conducting an investigation to better understand the geologic, hydrologic, and biogeochemical factors that control acid formation at road cuts. Road cuts with the potential for acid-rock drainage were identifed and evaluated in Middle and East Tennessee. The pyrite-bearing formations evaluated were the Chattanooga Shale (Devonian black shale), the Fentress Formation (coal-bearing), and the Precambrian Anakeesta Formation and similar Precambrian rocks. Conceptual models of the formation and transport of acid-rock drainage (ARD) from road cuts were developed based on the results of a literature review, site reconnaissance, and the initial rock and water sampling. The formation of ARD requires a combination of hydrologic, geochemical, and microbial interactions which affect drainage from the site, acidity of the water, and trace metal concentrations. The basic modes of ARD formation from road cuts are; 1 - seeps and springs from pyrite-bearing formations and 2 - runoff over the face of a road cut in a pyrite-bearing formation. Depending on site conditions at road cuts, the basic modes of ARD formation can be altered and the additional modes of ARD formation are; 3 - runoff over and through piles of pyrite-bearing material, either from construction or breakdown

  16. A simplified fracture network model for studying the efficiency of a single well semi open loop heat exchanger in fractured crystalline rock

    Science.gov (United States)

    de La Bernardie, Jérôme; de Dreuzy, Jean-Raynald; Bour, Olivier; Thierion, Charlotte; Ausseur, Jean-Yves; Lesuer, Hervé; Le Borgne, Tanguy

    2016-04-01

    Geothermal energy is a renewable energy source particularly attractive due to associated low greenhouse gas emission rates. Crystalline rocks are in general considered of poor interest for geothermal applications at shallow depths (energy storage at these shallow depths is still remaining very challenging because of the complexity of fractured media. The purpose of this study is to test the possibility of efficient thermal energy storage in shallow fractured rocks with a single well semi open loop heat exchanger (standing column well). For doing so, a simplified numerical model of fractured media is considered with few fractures. Here we present the different steps for building the model and for achieving the sensitivity analysis. First, an analytical and dimensional study on the equations has been achieved to highlight the main parameters that control the optimization of the system. In a second step, multiphysics software COMSOL was used to achieve numerical simulations in a very simplified model of fractured media. The objective was to test the efficiency of such a system to store and recover thermal energy depending on i) the few parameters controlling fracture network geometry (size and number of fractures) and ii) the frequency of cycles used to store and recover thermal energy. The results have then been compared to reference shallow geothermal systems already set up for porous media. Through this study, relationships between structure, heat exchanges and storage may be highlighted.

  17. A multidimensional horizontal-loop controlled-source electromagnetic inversion method and its use to characterize heterogeneity in aquiferous fractured crystalline rocks

    Science.gov (United States)

    Sasaki, Yutaka; Meju, Max A.

    2006-07-01

    The controlled-source dual horizontal-loop harmonic electromagnetic (HLEM) profiling method is well suited to the problem of investigating fracture zones in crystalline rocks but there are still limitations in the way that experimental data are currently interpreted-the use of 1-D data inversion leads to inaccurate determination of geological structure. To allow accurate characterization of zones of fractured rock especially underneath heterogeneous overburden, we have developed an efficient 2.5-D regularized inversion method for reconstructing subsurface electrical resistivity distributions from multifrequency HLEM data, with the forward problem solved in 3-D using a staggered-grid finite-difference method. The inversion method is validated using a synthetic example and practical data sets from four borehole sites in a granitic terrain in northeast Brazil. An appraisal of our results for sites with boreholes sited using conventional data analysis procedures shows that we can distinguish between optimally located productive wells in fracture-zone lineaments and those with diminished yields in weathered layer with no major underlying fracture zones. We suggest that 2.5-D inversion can aid in developing better strategies for sustainable groundwater resource development in the basement terrains.

  18. Application of Ground Phosphate Rock to Diminish the Effects of Simulated Acid Rain of Soil Properties

    Institute of Scientific and Technical Information of China (English)

    DONGYUAN-YAN; LIXUE-YUAN

    1992-01-01

    The effects of simulated acid rain retained in soil on the properties of acid soil and its diminishing by application of ground phosphate rock were investigated by using the sorption method.Results show as follows:(1)For yellow brown soil,the effect of simulated acid rain on the properties of soil with a pH value of 5.9 was relatively small,except a great quantity of acid rain deposited on it.(2) for red soil,the effect of simulated acid rain on the properties of soil was significant.With the increase of the amount of acid deposition,the pH value of soil was declined,but the contents of exchangeable H+,Al3+ and Mn2+ and the amount of SO41- retention were increased.(3) Many properties of acid soils could be improved by applying ground phosphate rock.For example,pH value of soils and the amounts of available P and exchangeable Ca2+ and Mg2+ were increased,and the amounts of exchangeable H+ and Al3+ and SO42- retained was reduced.The application of ground posphate rock could effctively diminish the pollution of acid rain to soil.

  19. Self-assembled multicompartment liquid crystalline lipid carriers for protein, peptide, and nucleic acid drug delivery.

    Science.gov (United States)

    Angelova, Angelina; Angelov, Borislav; Mutafchieva, Rada; Lesieur, Sylviane; Couvreur, Patrick

    2011-02-15

    Lipids and lipopolymers self-assembled into biocompatible nano- and mesostructured functional materials offer many potential applications in medicine and diagnostics. In this Account, we demonstrate how high-resolution structural investigations of bicontinuous cubic templates made from lyotropic thermosensitive liquid-crystalline (LC) materials have initiated the development of innovative lipidopolymeric self-assembled nanocarriers. Such structures have tunable nanochannel sizes, morphologies, and hierarchical inner organizations and provide potential vehicles for the predictable loading and release of therapeutic proteins, peptides, or nucleic acids. This Account shows that structural studies of swelling of bicontinuous cubic lipid/water phases are essential for overcoming the nanoscale constraints for encapsulation of large therapeutic molecules in multicompartment lipid carriers. For the systems described here, we have employed time-resolved small-angle X-ray scattering (SAXS) and high-resolution freeze-fracture electronic microscopy (FF-EM) to study the morphology and the dynamic topological transitions of these nanostructured multicomponent amphiphilic assemblies. Quasi-elastic light scattering and circular dichroism spectroscopy can provide additional information at the nanoscale about the behavior of lipid/protein self-assemblies under conditions that approximate physiological hydration. We wanted to generalize these findings to control the stability and the hydration of the water nanochannels in liquid-crystalline lipid nanovehicles and confine therapeutic biomolecules within these structures. Therefore we analyzed the influence of amphiphilic and soluble additives (e.g. poly(ethylene glycol)monooleate (MO-PEG), octyl glucoside (OG), proteins) on the nanochannels' size in a diamond (D)-type bicontinuous cubic phase of the lipid glycerol monooleate (MO). At body temperature, we can stabilize long-living swollen states, corresponding to a diamond cubic phase

  20. Effect of Heat Treatment and Layer Orientation on the Tensile Strength of a Crystalline Rock Under Brazilian Test Condition

    Science.gov (United States)

    Guha Roy, Debanjan; Singh, T. N.

    2016-05-01

    The effect of heat treatment and the layer orientation on the tensile properties of granitic gneiss were studied under the unconfined stress condition. The tensile strength of the samples was studied using a Brazilian configuration, and the geochemical and microstructural properties were studied using the X-ray diffraction technique as well as scanning electron microscopy (SEM), respectively. The fracture pattern and the geometrical analyses were performed using the digital photographs. The results show that both the heat treatment and layer orientation have strong control on the tensile strength, force-parallel and layer-parallel strains, and on the tensile fracture geometry. A general decrease in the tensile strength of the rock was documented with the increasing heat treatment. Although, in the heat-treated samples, X-ray diffraction study do not reveal any major change in the mineral composition, but the SEM shows the development of several micro-cracks in the grains. In the samples with different layer orientation, along with the changes in the tensile strength and layer-parallel to force-parallel strain ratio, the layer activation under shear stress is also noticed. Here, the ratio between the tensile to shear stress, acting along the layers is thought to be the major controlling factor of the tensile properties of rocks, which has many applications in mining, civil constructions, and waste disposal work.

  1. Consequences of using crushed crystalline rock as ballast in KBS-3 tunnels instead of rounded quartz particles

    International Nuclear Information System (INIS)

    The basic question has been whether such replacement alters the hydraulic conductivity and compressibility as well as expandability and also if the physical and chemical stabilities are altered. The key factor is the microstructural constitution of the bentonite/ballast mixtures, which is primarily controlled by the grain size distribution of the ballast. The compact ability of backfills with quartz sand (SB) is higher than that of backfills with crushed rock as ballast (RB). The physical stability of RB backfills in terms of piping and erosion resistance will be somewhat lower than that of SB backfills. The chemical stability is practically independent of whether the ballast is pure quartz or rock with K-bearing minerals because the temperature in the backfill will be too low to yield significant smectite to illite conversion in the short heating period. In order to reach the same densities of SB and RB backfills, which turn out to give fairly similar physical properties, the latter backfills need more effective compaction or, alternatively, a higher bentonite content. It is estimated that if the bentonite content in RB backfills is not increased while the density is enhanced to what is achievable, these backfills will serve equally well as SB backfills with the densities implied by the basic KBS-3 concept. 23 refs, 27 figs, 7 tabs

  2. The crystalline basement of Estonia: rock complexes of the Palaeoproterozoic Orosirian and Statherian and Mesoproterozoic Calymmian periods, and regional correlations

    Directory of Open Access Journals (Sweden)

    Kirs, Juho

    2009-12-01

    Full Text Available New data on the Fennoscandian Shield and the Baltic area suggest a need for reinterpretation of the stratigraphy of Estonian Precambrian rock complexes. The rocks of the Tallinn Zone formed in the framework of the Fennian orogeny at the margin of the Bergslagen microcontinent 1.90–1.88 Ga ago. The precise age of the Alutaguse Zone is not known. It may have formed either during the 1.93–1.91 Ga Lapland–Savo orogeny or as a rifted eastern part of the Tallinn Zone in the Fennian orogeny. The granulites of western and southern Estonia belong to the volcanic arcs inside the 1.84–1.80 Ga Svecobaltic orogenic belt and show peak metamorphic conditions of 1.78 Ga. Small shoshonitic plutons formed 1.83–1.63 Ga, the small granitic plutons of the Wiborg Rapakivi Subprovince 1.67–1.62 Ga, and the Riga pluton 1.59–1.54 Ga ago.

  3. Characterising and modelling the excavation damaged zone (EDZ) in crystalline rock in the context of radioactive waste disposal

    Energy Technology Data Exchange (ETDEWEB)

    Hudson, J.A.; Backstrom, A.; Rutqvist, J.; Jing, L.; Backers, T.; Chijimatsu, M.; Christiansson, R.; Feng, X.-T.; Kobayashi, A.; Koyama, T.; Lee, H.-S.; Neretnieks, I.; Pan, P.Z.; Rinne, M.; Shen, B.-T.

    2008-10-01

    This paper describes current knowledge about the nature of and potential for thermo-hydro-mechanical-chemical modelling of the Excavation Damaged Zone (EDZ) around the excavations for an underground radioactive waste repository. In the first part of the paper, the disturbances associated with excavation are explained, together with reviews of Workshops that have been held on the subject. In the second part of the paper, the results of a DECOVALEX research programme on modelling the EDZ are presented. Four research teams used four different models to simulate the complete stress-strain curve for Avro granite from the Swedish Aespoe Hard Rock Laboratory. Subsequent research extended the work to computer simulation of the evolution of the repository using a 'wall block model' and a 'near-field model'. This included assessing the evolution of stress, failure and permeability and time dependent effects during repository evolution. As discussed, all the computer models are well suited to sensitivity studies for evaluating the influence of their respective supporting parameters on the complete stress-strain curve for rock and for modelling the EDZ.

  4. A coupled mechanical-hydrological investigation of crystalline rocks: Annual technical progress report, proposed test matrix, and preliminary results

    International Nuclear Information System (INIS)

    This report reviews the Fracture Flow Behavior in Rock Study being performed at the Pacific Northwest Laboratory. The study's objective is to determine the feasibility of predicting mechanical-hydrological behavior of natural rock fractures by accurately characterizing fracture surface topography and mineralization. A laboratory-scale facility is currently being used to ensure optimum control of variables. Devising a technique to study small-scale samples is the first step to understanding the complex coupled processes encountered in geomechanics and hydrology. The major accomplishments during fiscal year 1987 were initial development of the innovative testing method, identification of appropriate specimens, substantial renovation to the facility, completion of several sets of experiments, and procurement of hardware components for a laser-imaging device used to characterize fracture surfaces. A complete set of preliminary results and findings is presented in this report. These results, gathered from a basalt core with a natural fracture, have demonstrated that the methodology is valid, and definite trends in the data are readily apparent. 10 refs., 14 figs., 1 tab

  5. A global sensitivity analysis of two-phase flow between fractured crystalline rock and bentonite with application to spent nuclear fuel disposal

    Science.gov (United States)

    Dessirier, Benoît; Frampton, Andrew; Jarsjö, Jerker

    2015-11-01

    Geological disposal of spent nuclear fuel in deep crystalline rock is investigated as a possible long term solution in Sweden and Finland. The fuel rods would be cased in copper canisters and deposited in vertical holes in the floor of deep underground tunnels, embedded within an engineered bentonite buffer. Recent experiments at the Äspö Hard Rock Laboratory (Sweden) showed that the high suction of unsaturated bentonite causes a de-saturation of the adjacent rock at the time of installation, which was also independently predicted in model experiments. Remaining air can affect the flow patterns and alter bio-geochemical conditions, influencing for instance the transport of radionuclides in the case of canister failure. However, thus far, observations and model realizations are limited in number and do not capture the conceivable range and combination of parameter values and boundary conditions that are relevant for the thousands of deposition holes envisioned in an operational final repository. In order to decrease this knowledge gap, we introduce here a formalized, systematic and fully integrated approach to study the combined impact of multiple factors on air saturation and dissolution predictions, investigating the impact of variability in parameter values, geometry and boundary conditions on bentonite buffer saturation times and on occurrences of rock de-saturation. Results showed that four parameters consistently appear in the top six influential factors for all considered output (target) variables: the position of the fracture intersecting the deposition hole, the background rock permeability, the suction representing the relative humidity in the open tunnel and the far field pressure value. The combined influence of these compared to the other parameters increases as one targets a larger fraction of the buffer reaching near-saturation. Strong interaction effects were found, which means that some parameter combinations yielded results (e.g., time to

  6. Brittle structures and their role in controlling porosity and permeability in a complex Precambrian crystalline-rock aquifer system in the Colorado Rocky Mountain front range

    Science.gov (United States)

    Caine, J.S.; Tomusiak, S.R.A.

    2003-01-01

    Expansion of the Denver metropolitan area has resulted in substantial residential development in the foothills of the Rocky Mountain Front Range. This type of sub-urban growth, characteristic of much of the semiarid intermountain west, often relies on groundwater from individual domestic wells and is exemplified in the Turkey Creek watershed. The watershed is underlain by complexly deformed and fractured crystalline bedrock in which groundwater resources are poorly understood, and concerns regarding groundwater mining and degradation have arisen. As part of a pilot project to establish quantitative bounds on the groundwater resource, an outcrop-based geologic characterization and numerical modeling study of the brittle structures and their controls on the flow system was initiated. Existing data suggest that ground-water storage, flow, and contaminant transport are primarily controlled by a heterogeneous array of fracture networks. Inspections of well-permit data and field observations led to a conceptual model in which three dominant lithologic groups underlying sparse surface deposits form the aquifer system-metamorphic rocks, a complex array of granitic intrusive rocks, and major brittle fault zones. Pervasive but variable jointing of each lithologic group forms the "background" permeability structure and is an important component of the bulk storage capacity. This "background" is cut by brittle fault zones of varying structural styles and by pegmatite dikes, both with much higher fracture intensities relative to "background" that likely make them spatially complex conduits. Probabilistic, discrete-fracture-network and finite-element modeling was used to estimate porosity and permeability at the outcrop scale using fracture network data collected in the field. The models were conditioned to limited aquifer test and borehole geophysical data and give insight into the relative hydraulic properties between locations and geologic controls on storage and flow

  7. An improved method for separating quartz from rock using pyrophosphoric acid

    International Nuclear Information System (INIS)

    A method that employs hot dehydrated phosphoric acid (pyrophosphoric acid) to isolate quartz from rock for surface exposure dating with 10Be and 26Al has been improved so that up to 250 g of sample can be decomposed reasonably safely. Because pyrophosphoric acid is more selective in dissolving the silicate minerals than the commonly used mixture of dilute hydrofluoric and nitric acids, the yield of quartz is relatively high. However, serious hazards arise from using large volumes of hot concentrated phosphoric acid to decompose rock. When the acid is heated to evaporate water and initiate the reaction, the crushed rock settles to the bottom of the vessel causing the mixture to superheat and 'bump' severely. Then, as the reaction progresses, the mixture increases in viscosity and will form a solid gel if allowed to cool. Starting with a greater excess of phosphoric acid to reduce the viscosity is impractical for such large amounts of rock so, to avoid a solid gel at the end of the reaction, the mixture has to be diluted with cold water while it is still near 250 degrees C. This step is particularly dangerous as the water at first instantaneously turns to steam that can eject gel resulting in serious thermal burns even through thick gloves. We have mitigated these hazards by keeping the sample suspended using a mixer throughout the procedure. There is no superheating at the start and water can be added slowly at the end thus quenching the reaction and dispersing the particulate matter. Another hazard, boiling sodium hydroxide solution, has been minimised and may ultimately be eliminated. This report covers the prototype mixer, safety features of the new mixer under construction, and an interim procedure for decomposing rock and recovering pure quartz. (author)

  8. Potential application of oxygen-18 and deuterium in mining effluent and acid rock drainage studies

    Energy Technology Data Exchange (ETDEWEB)

    Ghomshei, M.M. [British Columbia Univ., Vancouver, BC (Canada). Dept. of Mining and Mineral Process Engineering; Allen, D.M. [Simon Fraser Univ., Burnaby, BC (Canada). Dept. of Earth Sciences

    2000-05-01

    Oxygen-18 ({sup 18}O) and deuterium (D, or {sup 2}H) are routinely used in hydrologic, climatologic and geothermal studies. In hydrology, stable isotopes provide information on the type and topology (altitude and latitude) of the recharge waters and the historical effects on water, related to such physical processes as evaporation (in ponds) melting (of snow or ice), condensation, evapotranspiration and mixing. In geothermal studies, stable isotopes provide key information related to recharge and the various temperature-dependent water/rock isotope exchange reactions. The latter is assessed through the oxygen shift in the {sup 18}O/D correlation. At acid rock drainage (ARD) sites, water/rock interactions are primarily controlled by pH and oxidation potential. Using the isotopic characteristics of the rocks and the recharge waters as a basis, the relative oxygen shift of the ARD effluent can provide information on: (1) the residence time, (2) the rate of water/rock reactions, and (3) the actual pH at the rock/water interface. This paper offers a methodology for conducting oxygen and hydrogen isotope studies related to ARD and other mineral effluent problems. The methodology is based on: (1) comprehensive sampling of regional waters, ARD effluent and major contributing minerals and rocks, (2) isotopic and elemental analysis, and (3) data interpretation on the basis of zero-dimensional (mass balance), multi-component mixing model. (orig.)

  9. Magnetic properties, acid neutralization capacity, and net acid production of rocks in the Animas River Watershed Silverton, Colorado

    Science.gov (United States)

    McCafferty, Anne E.; Yager, Douglas B.; Horton, Radley M.; Diehl, Sharon F.

    2006-01-01

    Federal land managers along with local stakeholders in the Upper Animas River watershed near Silverton, Colorado are actively designing and implementing mine waste remediation projects to mitigate the effects of acid mine drainage from several abandoned hard rock metal mines and mills. Local source rocks with high acid neutralization capacity (ANC) within the watershed are of interest to land managers for use in these remediation projects. A suite of representative samples was collected from propylitic to weakly sericitic-altered volcanic and plutonic rocks exposed in outcrops throughout the watershed. Acid-base accounting laboratory methods coupled with mineralogic and geochemical characterization provide insight into lithologies that have a range of ANC and net acid production (NAP). Petrophysical lab determinations of magnetic susceptibility converted to estimates for percent magnetite show correlation with the environmental properties of ANC and NAP for many of the lithologies. A goal of our study is to interpret watershed-scale airborne magnetic data for regional mapping of rocks that have varying degrees of ANC and NAP. Results of our preliminary work are presented here.

  10. Characterization of fractures and flow zones in a contaminated crystalline-rock aquifer in the Tylerville section of Haddam, Connecticut

    Science.gov (United States)

    Johnson, Carole D.; Kiel, Kristal F.; Joesten, Peter K.; Pappas, Katherine L.

    2016-10-04

    The U.S. Geological Survey, in cooperation with the Connecticut Department of Energy and Environmental Protection, investigated the characteristics of the bedrock aquifer in the Tylerville section of Haddam, Connecticut, from June to August 2014. As part of this investigation, geophysical logs were collected from six water-supply wells and were analyzed to (1) identify well construction, (2) determine the rock type and orientation of the foliation and layering of the rock, (3) characterize the depth and orientation of fractures, (4) evaluate fluid properties of the water in the well, and (5) determine the relative transmissivity and head of discrete fractures or fracture zones. The logs included the following: caliper, electromagnetic induction, gamma, acoustic and (or) optical televiewer, heat-pulse flowmeter under ambient and pumped conditions, hydraulic head data, fluid electrical conductivity and temperature under postpumping conditions, and borehole-radar reflection collected in single-hole mode. In a seventh borehole, a former water-supply well, only caliper, fluid electrical conductivty, and temperature logs were collected, because of a constriction in the borehole.This report includes a description of the methods used to collect and process the borehole geophysical data, the description of the data collected in each of the wells, and a comparison of the results collected in all of the wells. The data are presented in plots of the borehole geophysical logs, tables, and figures. Collectively these data provide valuable characterizations that can be used to improve or inform site conceptual models of groundwater flow in the study area.

  11. Effect of time and temperature exposition in the crystallinity degree of sulfonated poly-(styrene acrylic acid) (PSAA-S)

    Energy Technology Data Exchange (ETDEWEB)

    Duarte, G.W.; Becker, E.B.; Silva, L.; Naspolini, A.M.; Consenso, E.C.; Paula, M.M.S.; Fiori, M.A., E-mail: glau_bn@hotmail.co [University of Extreme South of Santa Catarina Criciuma, SC (Brazil). Dept. of Materials Engineering; Silveira, F.Z. [Federal University of Santa Catarina (UFSC), Florianopolis, SC (Brazil). Dept. of Chemical Engineering

    2010-07-01

    Polymers with special properties have been increasingly applied in the development of technological devices. For example, polymeric materials with special electric properties, such as sulfonated poly-(styrene-acrylic acid) - PSAA-S, are of great interest for showing different conductivities depending on the environment where they are applied. The special properties of PSAA are obtained only after sulfonation step in acidic media. The present work aimed to evaluate the effect of time and temperature exposition in the crystallinity degree of PSAA-S, through a statistical experimental factorial planning. The samples of PSAA-S were submitted to FT-IR and DRX tests. The results showed that the temperature and the time of exposition are significant factors in the crystallinity degree of PSAA-S, considering that the crystal lattices created during the polymerization are damaged by the action of time and temperature at which the polymer is exposed. (author)

  12. Variscan terrane boundaries in the Odenwald-Spessart basement, Mid-German Crystalline Zone: New evidence from ocean ridge, intraplate and arc-derived metabasaltic rocks

    Science.gov (United States)

    Will, T. M.; Lee, S.-H.; Schmädicke, E.; Frimmel, H. E.; Okrusch, M.

    2015-04-01

    The Mid-German Crystalline Zone is part of a large Variscan suture and consists of various basement complexes that are exposed in central Germany. New lithogeochemical and Sr-Nd-Pb isotope data obtained on various amphibolites from the Odenwald-Spessart basement show that their protoliths formed in different tectonic settings and were subsequently incorporated into a subduction zone prior to Variscan continental collision. Metabasic rocks from the northernmost Spessart and the western Odenwald are geochemically almost identical and their protoliths are interpreted to have formed in an extensional, possibly, a back-arc setting. The tholeiitic and calc-alkaline rocks have intermediate TiO2 concentrations and high Th/Nb ratios, typical of volcanic arc-type and/or subduction-fluid modified rocks. The Nd initial ratios are depleted (εNd330 Ma = 5.0-5.8) and Nd model ages range from 660 to 610 Ma, which points at juvenile crustal addition towards the end of the Neoproterozoic. The samples define a linear array in 206Pb/204Pb versus 207Pb/204Pb space. In contrast, the protoliths of the metabasic rocks from the southern and central Spessart formed either in an intraplate oceanic island or a continental arc setting. The alkaline intraplate rocks from the southern Spessart basement are very TiO2-rich and have very low Th/Nb ratios. The rocks have weakly depleted Nd initals (εNd330 Ma = 2.6-3.3) and Nd model ages between 870 and 810 Ma. In contrast, the central Spessart within-plate rocks have considerably lower TiO2 concentrations but higher Th/Nb ratios. In addition, these rocks are isotopically enriched (εNd330 Ma = - 13.1 to - 9.5) and have Palaeoproterozoic Nd model ages. The continental arc rocks from the central and southern Spessart basement have low TiO2 concentrations and variable Th/Nb ratios. Mostly negative Nd initials (εNd330 Ma = - 2.6 to + 0.9) and late Mesoproterozoic Nd model ages indicate that recycling of older crust or mixing of crustal components of

  13. A review of acid drainage from waste rock dumps and mine sites (Australian and Scandinavia)

    International Nuclear Information System (INIS)

    This report reviews the literature from Australia and Scandinavia on acid drainage from pyritic waste rock dumps with an emphasis on measurements and theory of processes that control the rage of oxidation and the release of pollutants. Conditions within waste rock dumps have been measured at several mine sites and a range of rehabilitation treatments have been tried to reduce the release of pollutants. A number of models have been proposed to calculate air flow, water transport and geochemistry. The data and experience at the mine sites are compared with predictions of the models. Details of Australian and Swedish mine sites where waste rock is a source of acid drainage are described in the Appendices. 92 refs., 2 tabs., 10 figs

  14. PHYSICAL SOLUTIONS FOR ACID ROCK DRAINAGE AT REMOTE SITES DEMONSTRATION PROJECT

    Science.gov (United States)

    This report summarizes the results of Mine Waste Technology Program, Activity III, Project 42, Physical Solutions for Acid Rock Drainage at Remote Sites, funded by the U.S. Environmental Protection Agency (EPA) and jointly administered by EPA and the U.S. Department of Energy. A...

  15. COMPOST-FREE BIOREACTOR TREATMENT OF ACID ROCK DRAINAGE LEVIATHAN MINE, CALIFORNIA INNOVATIVE TECHNOLOGY EVALUATION REPORT

    Science.gov (United States)

    As part of the Superfund Innovative Technology Evaluation (SITE) program, an evaluation of the compost-free bioreactor treatment of acid rock drainage (ARD) from the Aspen Seep was conducted at the Leviathan Mine Superfund site located in a remote, high altitude area of Alpine Co...

  16. COMPOST-FREE BIOLOGICAL TREATMENT OF ACID ROCK DRAINAGE, TECHNICAL EVALUATION BULLETIN

    Science.gov (United States)

    As part of the Superfund Innovative Technology Evaluation (SITE) program, an evaluation of the compost-free bioreactor treatment of acid rock drainage (ARD) from the Aspen Seep was conducted at the Leviathan Mine Superfund site located in a remote, high altitude area of Alpine Co...

  17. COMPOST-FREE BIOREACTOR TREATMENT OF ACID ROCK DRAINAGE - TECHNOLOGY CAPSULE

    Science.gov (United States)

    As part of the Superfund Innovative Technology Evaluation (SITE) program, an evaluation of the compost-free bioreactor treatment of acid rock drainage (ARD) from the Aspen Seep was conducted at the Leviathan Mine Superfund site located in a remote, high altitude area of Alpine Co...

  18. Protective colloids and polylactic acid co-affecting the polymorphic crystal forms and crystallinity of indomethacin encapsulated in microspheres.

    Science.gov (United States)

    Lin, S Y; Chen, K S; Teng, H H

    1999-01-01

    The co-effect of protective colloids and polylactic acid (PLA) on the polymorphic crystal forms and crystallinity of indomethacin (IMC) in IMC-loaded PLA microspheres was investigated with differential scanning calorimetry, infrared spectroscopy and x-ray diffractometry, to evaluate the polymorphic crystal forms and crystallinity of IMC encapsulated in PLA microspheres. The surfactant, sodium dodecyl sulphate (SDS), was also used as a dispersing agent. The results indicate that the polymorphism and crystallinity of IMC encapsulated in IMC-loaded PLA microspheres was dependent on the type of protective colloid and PLA used. The amorphous state and alpha-form of IMC were found in the IMC-loaded PLA microspheres prepared using polysaccharide (pectin or beta-cyclodextrin) as a protective colloid or SDS as a dispersing agent. However, the amorphous and methylene chloride solvate of IMC seemed to exist in the IMC-loaded PLA microspheres prepared with the proteins (gelatin or albumin), synthetic cellulose derivative (methyl cellulose or hydroxylpropyl methylcellulose) or the synthetic nonionic polymer (polyvinyl alcohol, polyvinyl pyrrolidone or biosoluble polymer) as a protective colloid. PLA was found to express a certain crystallinity in microspheres and not be affected by the protective colloids, but it played a more important role in influencing the crystallization of IMC during microencapsulation than the protective colloids. No interaction occurred in the physical mixture of IMC and PLA, nor in the IMC-loaded PLA microspheres.

  19. An in-situ stimulation experiment in crystalline rock - assessment of induced seismicity levels during stimulation and related hazard for nearby infrastructure

    Science.gov (United States)

    Gischig, Valentin; Broccardo, Marco; Amann, Florian; Jalali, Mohammadreza; Esposito, Simona; Krietsch, Hannes; Doetsch, Joseph; Madonna, Claudio; Wiemer, Stefan; Loew, Simon; Giardini, Domenico

    2016-04-01

    A decameter in-situ stimulation experiment is currently being performed at the Grimsel Test Site in Switzerland by the Swiss Competence Center for Energy Research - Supply of Electricity (SCCER-SoE). The underground research laboratory lies in crystalline rock at a depth of 480 m, and exhibits well-documented geology that is presenting some analogies with the crystalline basement targeted for the exploitation of deep geothermal energy resources in Switzerland. The goal is to perform a series of stimulation experiments spanning from hydraulic fracturing to controlled fault-slip experiments in an experimental volume approximately 30 m in diameter. The experiments will contribute to a better understanding of hydro-mechanical phenomena and induced seismicity associated with high-pressure fluid injections. Comprehensive monitoring during stimulation will include observation of injection rate and pressure, pressure propagation in the reservoir, permeability enhancement, 3D dislocation along the faults, rock mass deformation near the fault zone, as well as micro-seismicity. The experimental volume is surrounded by other in-situ experiments (at 50 to 500 m distance) and by infrastructure of the local hydropower company (at ~100 m to several kilometres distance). Although it is generally agreed among stakeholders related to the experiments that levels of induced seismicity may be low given the small total injection volumes of less than 1 m3, detailed analysis of the potential impact of the stimulation on other experiments and surrounding infrastructure is essential to ensure operational safety. In this contribution, we present a procedure how induced seismic hazard can be estimated for an experimental situation that is untypical for injection-induced seismicity in terms of injection volumes, injection depths and proximity to affected objects. Both, deterministic and probabilistic methods are employed to estimate that maximum possible and the maximum expected induced

  20. Simulation of radio nuclide migration in crystalline rock under influence of matrix diffusion and sorption kinetics: Code development and pre-assessment of migration experiment

    Energy Technology Data Exchange (ETDEWEB)

    Woerman, A.; Xu Shulan [Uppsala Univ. (Sweden). Inst. of Earth Sciences

    1996-04-01

    The overall objective of the present study is to illuminate how spatial variability in rock chemistry in combination with spatial variability in matrix diffusion affects the radio nuclide migration along single fractures in crystalline rock. Models for ground water flow and transport of radio nuclides in a single fracture with micro-fissures have been formulated on the basis of generally accepted physical and chemical principles. Limits for the validity of the models are stated. The model equations are solved by combining finite differences and finite element methods in a computer code package. The computational package consists of three parts, namely, a stochastic field generator, a sub-program that solves the flow problem and a sub-program that solves the transport problem in a single fracture with connecting micro-fissures. Migration experiments have been pre-assessed by simulations of breakthrough curves for a constant concentration change at the upstream boundary. Breakthrough curves are sensitive to variations of parameters, such as, fracture aperture, porosity, distribution coefficient and advection velocity. The impact of matrix diffusion and sorption is manifested in terms of a retention of radionuclides causing a prolonged breakthrough. Heterogeneous sorption was characterized with a variable distribution coefficient for which the coefficient of variation CV(K{sub d})=1 and the integral scale of an exponential covariance function is one tenth of the drill core`s length. Simulated breakthrough curves for the heterogeneous sorption case have a relative variance of 3% in comparison to that of homogeneous case. An appropriate experimental set up for investigation of the effect of matrix diffusion and sorption on radio nuclide migration experiments would be an aperture less than 1 mm and porosity larger than 0.5%. 36 refs, 19 figs.

  1. 87Sr/86Sr-ratios and Sr-contents of deep ground waters, minerals and rocks from the crystalline and the Trias of Northern Switzerland

    International Nuclear Information System (INIS)

    In order to determine the origin of groundwaters and their interaction with the host rock, the amount and ratio of strontium isotopes in groundwaters, vein minerals, authigenic cements and whole rocks were measured in the crystalline basement and Triassic sediments of northern Switzerland. The groundwaters in the fractured basement aquifer generally show Sr-isotope ratios that range between 0.716 and 0.718. These ratios in the groundwaters are mainly determined by reaction with Sr-rich minerals that were formed during a Permian hydrothermal event. With minor exceptions, the Sr-isotope ratios of most vein minerals are not in equilibrium with those of the present groundwaters. The waters of the Buntsandstein aquifer are characterized by slightly lower Sr-isotope ratios and a higher Sr-content than in the corresponding basement aquifer waters. Buntsandstein waters are considered to have evolved from the waters of the basement aquifer through dissolution of calcite and sulphate present in the Buntsandstein. Although the Sr-isotope ratios in Buntsandstein vein minerals and waters are similar the relative amount of Sr (assuming equilibrium partitioning) suggests these vein minerals did not precipitate from the present waters. The much lower Sr-isotope ratio characteristic of waters in the Muschelkalk aquifer (0.708 to 0.709) readily distinguishes these from the Buntsandstein and basement waters. The low Sr-isotope ratios in the Muschelkalk waters are, however, higher than those measured from marine sulphates in the Muschelkalk, and may result from dissolution of dolomite and continental sulphates. Measured variations in the Sr-isotope ratios of successive authigenic minerals indicate that the Sr-isotope composition in the groundwaters fluctuated through geological time. (author) 32 refs., 4 figs., 1 tab

  2. Effect of emulsifiers and their liquid crystalline structures in emulsions on dermal and transdermal delivery of hydroquinone, salicylic acid and octadecenedioic acid.

    Science.gov (United States)

    Otto, A; Wiechers, J W; Kelly, C L; Dederen, J C; Hadgraft, J; du Plessis, J

    2010-01-01

    This study investigated the effect of emulsifiers and their liquid crystalline structures on the dermal and transdermal delivery of hydroquinone (HQ), salicylic acid (SA) and octadecenedioic acid (DIOIC). Emulsions containing liquid crystalline phases were compared with an emulsion without liquid crystals. Skin permeation experiments were performed using Franz-type diffusion cells and human abdominal skin dermatomed to a thickness of 400 mum. The results indicate that emulsifiers arranging in liquid crystalline structures in the water phase of the emulsion enhanced the skin penetration of the active ingredients with the exception of SA. SA showed a different pattern of percutaneous absorption, and no difference in dermal and transdermal delivery was observed between the emulsions with and without liquid crystalline phases. The increase in skin penetration of HQ and DIOIC could be attributed to an increased partitioning of the actives into the skin. It was hypothesized that the interaction between the different emulsifiers and active ingredients in the formulations varied and, therefore, the solubilization capacities of the various emulsifiers and their association structures.

  3. Controls on {sup 222}Rn variations in a fractured crystalline rock aquifer evaluated using aquifer tests and geophysical logging

    Energy Technology Data Exchange (ETDEWEB)

    Folger, P.F. [Office of Senator Pete V. Domenici, Washington, DC (United States)]|[Colorado School of Mines, Golden, CO (United States). Dept. of Geology and Geologic Engineering; Poeter, E. [Colorado School of Mines, Golden, CO (United States). Dept. of Geology and Geologic Engineering; Wanty, R.B.; Frishman, D.; Day, W.

    1996-03-01

    Concentrations of {sup 222}Rn in ground water may vary considerably within megascopically homogeneous rocks over relatively short distances. Calculations indicate that different hydraulic apertures of water-bearing fractures may account for variations in dissolved {sup 222}Rn concentration measured in domestic water wells completed in fractured Pikes Peak Granite, assuming that all other factors influencing dissolved {sup 222}Rn concentrations are constant. Concentrations of dissolved {sup 222}Rn range from 124 to 840 kBq/m{sup 3} [3,360 to 22,700 picocuries/liter] within a 2.5 km{sup 2} well field. Aquifer tests show that transmissivities range from 0.072 to 160 m{sup 2}/day within the well field. Acoustic televiewer and heat-pulse flow meter logging of four wells reveals that, despite tens to hundreds of fractures that intersect each well, a single fracture supplies all the flow to three wells, and one fracture provides 65% of the flow to the fourth well. Type-curve interpretation of early-time data from aquifer tests reveals classic half-slope behavior on log-log plots of drawdown versus time for two wells, suggesting linear flow to a single fracture. Drawdown versus time for the other two wells indicates radial or pseudo-radial flow, which suggests a higher degree of fracture interconnectivity near those boreholes. Hydraulic apertures calculated using the cubic law are 0.024 and 0.038 cm for producing fractures in the first hydraulically connected well pair and 0.011 and 0.020 cm for flowing fractures in the second well pair. Assuming uniform distribution of {sup 226}Ra along fracture walls and long residence time of water relative to {sup 222}Rn decay, the ratio of fracture apertures should equal the inverse ratio of {sup 222}Rn concentration in each well. Differences in {sup 222}Rn concentration between wells in the hydraulically connected pairs can be attributed solely to differences in hydraulic aperture.

  4. Comparative plasma pharmacokinetics of ceftiofur sodium and ceftiofur crystalline-free acid in neonatal calves.

    Science.gov (United States)

    Woodrow, J S; Caldwell, M; Cox, S; Hines, M; Credille, B C

    2016-06-01

    The objective of this study was to compare the plasma pharmacokinetic profile of ceftiofur crystalline-free acid (CCFA) and ceftiofur sodium in neonatal calves between 4 and 6 days of age. In one group (n = 7), a single dose of CCFA was administered subcutaneously (SQ) at the base of the ear at a dose of 6.6 mg/kg of body weight. In a second group (n = 7), a single dose of ceftiofur sodium was administered SQ in the neck at a dose of 2.2 mg/kg of body weight. Concentrations of desfuroylceftiofur acetamide (DCA) in plasma were determined by HPLC. Median time to maximum DCA concentration was 12 h (range 12-48 h) for CCFA and 1 h (range 1-2 h) for ceftiofur sodium. Median maximum plasma DCA concentration was significantly higher for calves given ceftiofur sodium (5.62 μg/mL; range 4.10-6.91 μg/mL) than for calves given CCFA (3.23 μg/mL; range 2.15-4.13 μg/mL). AUC0-∞ and Vd/F were significantly greater for calves given CCFA than for calves given ceftiofur sodium. The median terminal half-life of DCA in plasma was significantly longer for calves given CCFA (60.6 h; range 43.5-83.4 h) than for calves given ceftiofur sodium (18.1 h; range 16.7-39.7 h). Cl/F was not significantly different between groups. The duration of time median plasma DCA concentrations remained above 2.0 μg/mL was significantly longer in calves that received CCFA (84.6 h; range 48-103 h) as compared to calves that received ceftiofur sodium (21.7 h; range 12.6-33.6 h). Based on the results of this study, CCFA administered SQ at a dose of 6.6 mg/kg in neonatal calves provided plasma concentrations above the therapeutic target of 2 μg/mL for at least 3 days following a single dose. It is important to note that the use of ceftiofur-containing products is restricted by the FDA and the use of CCFA in veal calves is strictly prohibited. PMID:26542633

  5. Agronomic Potential of Partially Acidulated Rock Phosphates in Acid Soils of Subtropical China

    Institute of Scientific and Technical Information of China (English)

    XIONGLI-MING; B.TRUONG; 等

    1995-01-01

    A glasshouse experiment was conducted to evaluate the agronomic potential of four partially acidulated rock phosphates(PARP) in three representative solis sampled from subtripical China.The PARPs were manufactured by attacking a moderately reactive phosphate rock either with sulfuric acid alone or with combination of sulfuric and phosphoric acids at 30 or 60 percent of acidulation.Shoot dry weight and P accumulation of six successive cuttings of ryegrass were used to compare the agronomic potential of these fertilizers with that of the raw rock phosphate(RP) and monocalcium phosphate (MCP).Results indicated that the effectiveness of various phosphates was determined both by the solubility of the phosphates and by the acidity and P-fixing capacity of the soils.The higher the watersoluble P contained,the better the effectiveness of the fertilizer was.Although plant P accumulation of PARP treatments was constantly lower than that of MCP treatment,some PARPs could still get a dry matter production similar to that of MCP treatment.PARP SP60,which was acidulated with a mixture of sulfuric acid and phosphoric acid at 60 percent of acidulation and contained the highest soluble,P,was as effective as MCP in terms of dry matter production on all the soils.S60 and C1 which were both acidulated with sulfuric acid with the former at 60 percent of acidulation and the latter at 30 percent but with a further addition of monoammonium phosphate,were more than 80 percent as efective as MCP,Raw RP also showed a reasonable effectiveness which increased with soil acidity.It was suggested from the study that some of these APRPs could be expected to have a comparable field performance as soluble P fertilizers in the acid soil regions.

  6. Geochemistry of oil in fluid inclusions in a middle Proterozoic igneous intrusion: implications for the source of hydrocarbons in crystalline rocks

    Energy Technology Data Exchange (ETDEWEB)

    Dutkiewicz, A. [Sydney Univ., NSW (Australia). School of Geosciences; Sydney Univ., NSW (Australia). Inst. of Marine Science; Volk, H.; George, S.C. [CSIRO Petroleum, North Ryde, NSW (Australia); Ridley, J. [Macquarie Univ., Sydney, NSW (Australia). Dept. of Earth and Planetary Sciences

    2004-08-01

    The ca. 1280 Ma dolerite sill within the Mesoproterozoic Roper Group in the Roper Superbasin, Australia, contains evidence for at least two episodes of hydrocarbon migration represented, respectively, by solid bitumen with a ketone-rich extract, and a mixture of a high maturity gas-condensate and a lower maturity oil within oil-bearing fluid inclusions. The ketone isomers are formed by flash pyrolysis of kerogen during the intrusion of the dolerite sill [Org.Geochem. 21(1994) 829] and represent the first and oldest phase of hydrocarbon migration. The gas condensate and oil were subsequently trapped as a mixture within fluid inclusions at diagenetic temperatures and pressures of around 110 {sup o}C and 250 bars, significantly after cooling of the sill and likely during the Neoproterozoic reactivation of the Roper Superbasin. Either (1) these fluids migrated together and mixed in the reservoir or (2) an earlier oil charge was flushed by a later condensate charge and the oil-condensate mixture was trapped within single fluid inclusions. Oil inclusions occur chiefly within albitised zones of labradorite laths within the dolerite matrix, and within transcrystalline microfractures cutting vein calcite and rarely vein quartz. Oil inclusions trapped in the vein calcite are accompanied by hypersaline Ca/Mg brines. Gas chromatography-mass spectrometry of oil extracted from inclusions within the dolerite matrix shows that the oil is non-biodegraded and was therefore trapped relatively quickly within the host minerals. Trace amounts of biomarkers indicate that the inclusion oil is of a biogenic origin and excludes any abiotic processes that are apparent sources of hydrocarbons in many crystalline rocks. Monomethylalkanes, pentacyclic terpanes chiefly comprising hopanes and diahopanes, and very low concentrations of steranes and diasteranes indicate input from cyanobacterial organic matter with a minor contribution from eukaryotes. The hydrocarbons are likely derived from

  7. FEBEX project: full-scale engineered barriers experiment for a deep geological repository for high level radioactive waste in crystalline host rock. Final report

    International Nuclear Information System (INIS)

    FEBEX has the multiple objective of demonstrating the feasibility of manufacturing, handling and constructing the engineered barriers and of developing codes for the thermo-hydro-mechanical and thermo-hydro-geochemical performance assessment of a deep geological repository for high level radioactive wastes. These objectives require integrated theoretical and experimental development work. The experimental work consists of three parts: an in situ test, a mock-up test and a series of laboratory tests. The experiments is based on the Spanish reference concept for crystalline rock, in which the waste capsules are placed horizontally in drifts surround by high density compacted bentonite blocks. In the two large-scale tests, the thermal effects of the wastes were simulated by means of heaters; hydration was natural in the in situ test and controlled in the mock-up test. The large-scale tests, with their monitoring systems, have been in operation for more than two years. the demonstration has been achieved in the in situ test and there are great expectation that numerical models sufficiently validated for the near-field performance assessment will be achieved. (Author)

  8. FEBEX project: full-scale engineered barriers experiment for a deep geological repository for high level radioactive waste in crystalline host rock

    Energy Technology Data Exchange (ETDEWEB)

    Alberid, J.; Barcala, J. M.; Campos, R.; Cuevas, A. M.; Fernandez, E. [Ciemat. Madrid (Spain)

    2000-07-01

    FEBEX has the multiple objective of demonstrating the feasibility of manufacturing, handling and constructing the engineered barriers and of developing codes for the thermo-hydro-mechanical and thermo-hydro-geochemical performance assessment of a deep geological repository for high level radioactive wastes. These objectives require integrated theoretical and experimental development work. The experimental work consists of three parts: an in situ test, a mock-up test and a series of laboratory tests. The experiments is based on the Spanish reference concept for crystalline rock, in which the waste capsules are placed horizontally in drifts surround by high density compacted bentonite blocks. In the two large-scale tests, the thermal effects of the wastes were simulated by means of heaters; hydration was natural in the in situ test and controlled in the mock-up test. The large-scale tests, with their monitoring systems, have been in operation for more than two years. the demonstration has been achieved in the in situ test and there are great expectation that numerical models sufficiently validated for the near-field performance assessment will be achieved. (Author)

  9. Geothermal properties of deep crystalline rock formations in the Rhone valley - Preliminary study; Geothermie du cristallin profond de la vallee du Rhone - Etude preliminaire

    Energy Technology Data Exchange (ETDEWEB)

    Bianchetti, G.; Crestin, G. [Alpgeo Sarl, Sierre (Switzerland); Kohl, T. [Geowatt AG, Zuerich (Switzerland); Graf, G. [Bureau de service et d' ingenierie BSI SA, Lausanne (Switzerland)

    2006-07-01

    This report prepared for the Swiss Federal Office of Energy (SFOE) examines the possibility of cogenerating electric power and heat from geothermal energy stored in deep aquifers in the southwestern Swiss Alps. The project AGEPP (Alpine Geothermal Power Production) investigates an alternative to the well known Hot-Dry-Rock systems by looking at the crystalline formations in the alpine Rhone valley. Since centuries, these formations have been utilized for thermal spas. Two locations, Brigerbad and Lavey-les-Bains have been evaluated in the present report by the companies ALPGEO Sarl, GEOWATT AG and BSI SA. Existing boreholes at both locations show ample flow and substantial temperature gradients down to 600 meters, suggesting possible reservoir temperatures above 110 {sup o}C and a low mineralization (below 5 grams per liter). Flow rates of 50 to 75 liters/s at 110 {sup o}C seem possible and could be utilized in an ORC (Organic Rankine Cycle) for power production up to 1.3 MW. The power production costs are estimated at 0.08 CHF/kWh (singlet system) and 0.27 CHF/kWh (doublet system) respectively. The study implies that cogenerated heat is sold at a price of 0.08 CHF/kWh. These prices could compete with other alternative energies. Phase 2 of the project will evaluate the feasibility at the location of Lavey-les-Bains.

  10. Fractures inside crystalline rocks. Effects of deformations on fluid circulations; Fractures dans les roches cristallines. Effets des deformations sur les circulations de fluides

    Energy Technology Data Exchange (ETDEWEB)

    Gentier, S

    2005-07-01

    The modeling of fluid flows inside granite massifs is an important task for the evaluation of the feasibility of radioactive waste storage inside such formations. This document makes a synthesis of the works carried out since about 15 years, in particular by the French bureau of geological and mining research (BRGM), about the hydro-mechanical behaviour of a fracture and about the hydrodynamical characterization of fracture networks inside crystalline rocks: 1 - introduction; 2 - hydro-mechanical behaviour under normal stress: experimental results (hydro-mechanical behaviour, flow regimes, mechanical behaviour, test protocol, complementary tests, influence of samples size), geometrical interpretation of experimental results (relation with walls geometry, relation with voids geometry, relation with contacts geometry), hydro-mechanical modeling (hydraulic modeling, mechanical modeling); 3 - from the hydro-mechanical behaviour under normal stress to the coupling with heat transfers and chemistry: experiment for the study of the chemo-thermo-hydro-mechanical coupling (experimental results, relation with walls morphology), thermo-hydro-mechanical experiments, thermo-hydro-chemical experiments with fractures, conclusions; 4 - hydro-mechanical behaviour during shear: experimental results, geometrical interpretation (relation with the geometry of damaged zones, relation with voids geometry, relation with walls geometry), hydro-mechanical modeling (mechanical modeling, hydro-mechanical modeling of the behaviour during shear). (J.S.)

  11. Effects of humic acid on adsorption of actinide elements on rocks and others

    Energy Technology Data Exchange (ETDEWEB)

    Ohashi, Masakazu; Sato, Seichi; Ohashi, Hiroshi [Hokkaido Univ., Sapporo (Japan). Faculty of Engineering; Sakamoto, Yoshiaki; Nagao, Seiya; Onuki, Toshihiko; Senoo, Muneaki

    1996-01-01

    Since the transfer rates of radionuclides are reduced by their adsorption to rocks and soils, it is essential to elucidate the adsorption process for safety assessment of their geological disposal. In this study, adsorption of Np(V) to goethite, one of the widely distributed minerals was investigated as functions of pH and humic acid concentration. The surface charge density of goethite was determined and the zero charge point was 6.2 for synthesized and 6.4 for natural goethite. Since the point for humic acid was 4.5, adsorption sites for humic acid were reduced as the increase of negative charge density above pH6, resulting in a decrease in its adsorption rate. Np(V) adsorption to goethite was raised by the presence of humic acid in the range of 0-10ppm because the surface charge on the rock was shifted to negative by the adsorption of humic acid, resulting in easy adsorption of NpO{sub 2}{sup +}, which is stable in the condition below pH 9.5. On the other hand, humic acid adsorption was saturated at a concentration higher than 50 ppm, but its content in the solution would increase. Thus, it was thought that Np(V)-humic acid complex becomes more stable, resulting in the decrease in Np(V) adsorption rate. (M.N.)

  12. Acidic Microenvironments in Waste Rock Characterized by Neutral Drainage: Bacteria–Mineral Interactions at Sulfide Surfaces

    Directory of Open Access Journals (Sweden)

    John W. Dockrey

    2014-03-01

    Full Text Available Microbial populations and microbe-mineral interactions were examined in waste rock characterized by neutral rock drainage (NRD. Samples of three primary sulfide-bearing waste rock types (i.e., marble-hornfels, intrusive, exoskarn were collected from field-scale experiments at the Antamina Cu–Zn–Mo mine, Peru. Microbial communities within all samples were dominated by neutrophilic thiosulfate oxidizing bacteria. However, acidophilic iron and sulfur oxidizers were present within intrusive waste rock characterized by bulk circumneutral pH drainage. The extensive development of microbially colonized porous Fe(III (oxyhydroxide and Fe(III (oxyhydroxysulfate precipitates was observed at sulfide-mineral surfaces during examination by field emission-scanning electron microscopy-energy dispersive X-ray spectroscopy (FE-SEM-EDS. Linear combination fitting of bulk extended X-ray absorption fine structure (EXAFS spectra for these precipitates indicated they were composed of schwertmannite [Fe8O8(OH6–4.5(SO41–1.75], lepidocrocite [γ-FeO(OH] and K-jarosite [KFe3(OH6(SO42]. The presence of schwertmannite and K-jarosite is indicative of the development of localized acidic microenvironments at sulfide-mineral surfaces. Extensive bacterial colonization of this porous layer and pitting of underlying sulfide-mineral surfaces suggests that acidic microenvironments can play an important role in sulfide-mineral oxidation under bulk circumneutral pH conditions. These findings have important implications for water quality management in NRD settings.

  13. A Methodology to Hydraulically Parameterize Deformation Zones and Fracture Networks in Fractured Crystalline Rock Using Fracture Borehole Data and Inflow Data from Single- Hole Tests

    Science.gov (United States)

    Follin, S.; Hartley, L.; Rhen, I.; Selroos, J.

    2008-12-01

    Three-dimensional, regional, numerical models of groundwater flow and solute transport in fractured crystalline rock are used for two sites in Sweden that are considered for geological disposal of spent nuclear fuel. The models are used to underpin the conceptual modeling that is based on multi-disciplinary data and include descriptions of the geometry of geological features (deformation zones and fracture networks), transient hydrological and chemical boundary conditions, strong spatial heterogeneity in the hydraulic properties, density driven flow, solute transport including rock matrix diffusion, and mixing of different water types in a palaeo-hydrogeological perspective (last 10,000 years). The general approach applied in the numerical modeling was to first parameterize the deformation zones and fracture networks hydraulically using fracture and inflow data from single-hole tests. Second, a confirmatory step was attempted using essentially the same groundwater flow and solute transport model in terms of grid discretization and parameter settings for matching three types of independent field data: 1) large-scale cross-hole (interference) tests, 2) long- term monitoring of groundwater levels, and 3) hydrochemical composition of fracture water and matrix pore water in deep boreholes. We demonstrate here the adopted modelling approach for the first step, i.e. hydraulic parameterization of deformation zones and fracture networks, using single-hole test data from the site investigations undertaken at one of the sites in Sweden (Forsmark). The adopted modelling approach combines a deterministic representation of the major deformation zones with a stochastic representation of the less fractured bedrock outside these zones using the discrete fracture network (DFN) concept. An exponential model for the depth dependency of the in-plane deformation zone transmissivity was suggested based on the data. Lateral heterogeneity was simulated by adding a log-normal random deviate

  14. Effects of bacterial action on waste rock producing acid drainage in the Brazilian first uranium mine

    International Nuclear Information System (INIS)

    This work is an evolution of the methodology showed in the paper 'Study of waste of waste rock piles producing acid drainage in the Brazilian first uranium mine', also submitted for INAC2009. Therefore, the present work also related to the determination of chemical species leaching from waste rock pile 4 (WRP4) of the Uranium Mine and Milling Facility located in the Pocos de Caldas Plateau, as well as the generation of acid waters. With the previous experimental setup, it has been observed that not only water and available oxygen are significant to pyrite oxidation reaction, but bacterial activity as well. As a first approach, the present work addresses the same experiment, but now testing without the influence of bacterial action. Therefore, the new methodology and experimental setup is now capable of determining the acidity of water in contact with material from the WRP4 and the concentration of chemical species dissolved as function of time. Such would also show the extent of bacterial action interference on the pyrite oxidation reaction. Results are based on mass balances comparing concentrations of chemical species in the waste rock before the experiment and in the waste rock plus the remaining water after the experiment. In addition, the evolution of the pH and EMF (electromotive force) values along with chemical species quantified through the experiment are presented through graphics. That is followed by discussions on the significance of such results in terms of concentration of the involved chemical species. The present work has also shown the need of improving the injection of air into the system. A more sophisticated experimental setup should be assembled in the near future, which would allow the quantification of differences between experimental tests with and without bacterial action. (author)

  15. Rho Kinase ROCK2 Mediates Acid-Induced NADPH Oxidase NOX5-S Expression in Human Esophageal Adenocarcinoma Cells

    Science.gov (United States)

    Cao, Weibiao

    2016-01-01

    Mechanisms of the progression from Barrett’s esophagus (BE) to esophageal adenocarcinoma (EA) are not fully understood. We have shown that NOX5-S may be involved in this progression. However, how acid upregulates NOX5-S is not well known. We found that acid-induced increase in NOX5-S expression was significantly decreased by the Rho kinase (ROCK) inhibitor Y27632 in BE mucosal biopsies and FLO-1 EA cells. In addition, acid treatment significantly increased the Rho kinase activity in FLO-1 cells. The acid-induced increase in NOX5-S expression and H2O2 production was significantly decreased by knockdown of Rho kinase ROCK2, but not by knockdown of ROCK1. Conversely, the overexpression of the constitutively active ROCK2, but not the constitutively active ROCK1, significantly enhanced the NOX5-S expression and H2O2 production. Moreover, the acid-induced increase in Rho kinase activity and in NOX5-S mRNA expression was blocked by the removal of calcium in both FLO-1 and OE33 cells. The calcium ionophore A23187 significantly increased the Rho kinase activity and NOX5-S mRNA expression. We conclude that acid-induced increase in NOX5-S expression and H2O2 production may depend on the activation of ROCK2, but not ROCK1, in EA cells. The acid-induced activation of Rho kinase may be mediated by the intracellular calcium increase. It is possible that persistent acid reflux present in BE patients may increase the intracellular calcium, activate ROCK2 and thereby upregulate NOX5-S. High levels of reactive oxygen species derived from NOX5-S may cause DNA damage and thereby contribute to the progression from BE to EA. PMID:26901778

  16. Rho Kinase ROCK2 Mediates Acid-Induced NADPH Oxidase NOX5-S Expression in Human Esophageal Adenocarcinoma Cells.

    Directory of Open Access Journals (Sweden)

    Jie Hong

    Full Text Available Mechanisms of the progression from Barrett's esophagus (BE to esophageal adenocarcinoma (EA are not fully understood. We have shown that NOX5-S may be involved in this progression. However, how acid upregulates NOX5-S is not well known. We found that acid-induced increase in NOX5-S expression was significantly decreased by the Rho kinase (ROCK inhibitor Y27632 in BE mucosal biopsies and FLO-1 EA cells. In addition, acid treatment significantly increased the Rho kinase activity in FLO-1 cells. The acid-induced increase in NOX5-S expression and H2O2 production was significantly decreased by knockdown of Rho kinase ROCK2, but not by knockdown of ROCK1. Conversely, the overexpression of the constitutively active ROCK2, but not the constitutively active ROCK1, significantly enhanced the NOX5-S expression and H2O2 production. Moreover, the acid-induced increase in Rho kinase activity and in NOX5-S mRNA expression was blocked by the removal of calcium in both FLO-1 and OE33 cells. The calcium ionophore A23187 significantly increased the Rho kinase activity and NOX5-S mRNA expression. We conclude that acid-induced increase in NOX5-S expression and H2O2 production may depend on the activation of ROCK2, but not ROCK1, in EA cells. The acid-induced activation of Rho kinase may be mediated by the intracellular calcium increase. It is possible that persistent acid reflux present in BE patients may increase the intracellular calcium, activate ROCK2 and thereby upregulate NOX5-S. High levels of reactive oxygen species derived from NOX5-S may cause DNA damage and thereby contribute to the progression from BE to EA.

  17. Use of borehole-geophysical logs and hydrologic tests to characterize crystalline rock for nuclear-waste storage, Whiteshell Nuclear Research Establishment, Manitoba, and Chalk River Nuclear Laboratory, Ontario, Canada

    International Nuclear Information System (INIS)

    A number of borehole methods were used in the investigation of crystalline rocks at Whiteshell Nuclear Research Establishment and Chalk River Nuclear Laboratory in Canada. The selection of a crystalline-rock mass for the storage of nuclear waste likely will require the drilling and testing of a number of deep investigative boreholes in the rock mass. Although coring of at least one hole in each new area is essential, methods for making in-situ geophysical and hydrologic measurements can substitute for widespread coring and result in significant savings in time and money. Borehole-geophysical logging techniques permit the lateral extrapolation of data from a core hole. Log response is related to rock type, alteration, and the location and character of fractures. The geophysical logs that particularly are useful for these purposes are the acoustic televiewer and acoustic waveform, neutron and gamma, resistivity, temperature, and caliper. The acoustic-televiewer log of the borehole wall can provide high resolution data on the orientation and apparent width of fractures. In situ hydraulic tests of single fractures or fracture zones isolated by packers provide quantitative information on permeability, extent, and interconnection. The computer analysis of digitized acoustic waveforms has identified a part of the waveform that has amplitude variations related to permeabilities measured in the boreholes by packer tests. 38 refs., 37 figs., 4 tabs

  18. Aerobic bacterial pyrite oxidation and acid rock drainage during the Great Oxidation Event.

    Science.gov (United States)

    Konhauser, Kurt O; Lalonde, Stefan V; Planavsky, Noah J; Pecoits, Ernesto; Lyons, Timothy W; Mojzsis, Stephen J; Rouxel, Olivier J; Barley, Mark E; Rosìere, Carlos; Fralick, Phillip W; Kump, Lee R; Bekker, Andrey

    2011-10-19

    The enrichment of redox-sensitive trace metals in ancient marine sedimentary rocks has been used to determine the timing of the oxidation of the Earth's land surface. Chromium (Cr) is among the emerging proxies for tracking the effects of atmospheric oxygenation on continental weathering; this is because its supply to the oceans is dominated by terrestrial processes that can be recorded in the Cr isotope composition of Precambrian iron formations. However, the factors controlling past and present seawater Cr isotope composition are poorly understood. Here we provide an independent and complementary record of marine Cr supply, in the form of Cr concentrations and authigenic enrichment in iron-rich sedimentary rocks. Our data suggest that Cr was largely immobile on land until around 2.48 Gyr ago, but within the 160 Myr that followed--and synchronous with independent evidence for oxygenation associated with the Great Oxidation Event (see, for example, refs 4-6)--marked excursions in Cr content and Cr/Ti ratios indicate that Cr was solubilized at a scale unrivalled in history. As Cr isotope fractionations at that time were muted, Cr must have been mobilized predominantly in reduced, Cr(III), form. We demonstrate that only the oxidation of an abundant and previously stable crustal pyrite reservoir by aerobic-respiring, chemolithoautotrophic bacteria could have generated the degree of acidity required to solubilize Cr(III) from ultramafic source rocks and residual soils. This profound shift in weathering regimes beginning at 2.48 Gyr ago constitutes the earliest known geochemical evidence for acidophilic aerobes and the resulting acid rock drainage, and accounts for independent evidence of an increased supply of dissolved sulphate and sulphide-hosted trace elements to the oceans around that time. Our model adds to amassing evidence that the Archaean-Palaeoproterozoic boundary was marked by a substantial shift in terrestrial geochemistry and biology.

  19. Assessing amino acid racemization variability in coral intra-crystalline protein for geochronological applications

    OpenAIRE

    Hendy, Erica J.; Tomiak, Peter J.; Collins, Matthew J.; Hellstrom, John; Tudhope, Alexander W.; Lough, Janice M.; Penkman, Kirsty E. H.

    2012-01-01

    Over 500 Free Amino Acid (FAA) and corresponding Total Hydrolysed Amino Acid (THAA) analyses were completed from eight independently-dated, multi-century coral cores of massive Porites sp. colonies. This dataset allows us to re-evaluate the application of amino acid racemization (AAR) for dating late Holocene coral material, 20 years after Goodfriend et al. (GCA 56 (1992), 3847) first showed AAR had promise for developing chronologies in coral cores. This re-assessment incorporates recent met...

  20. N-Co-O Triply Doped Highly Crystalline Porous Carbon: An Acid-Proof Nonprecious Metal Oxygen Evolution Catalyst.

    Science.gov (United States)

    Yang, Shiliu; Zhan, Yi; Li, Jingfa; Lee, Jim Yang

    2016-02-10

    In comparison with nonaqueous Li-air batteries, aqueous Li-air batteries are kinetically more facile and there is more variety of non-noble metal catalysts available for oxygen electrocatalysis, especially in alkaline solution. The alkaline battery environment is however vulnerable to electrolyte carbonation by atmospheric CO2 resulting in capacity loss over time. The acid aqueous solution is immune to carbonation but is limited by the lack of effective non-noble metal catalysts for the oxygen evolution reaction (OER). This is contrary to the oxygen reduction reaction (ORR) in acid solution where a few good candidates exist. We report here the development of a N-Co-O triply doped carbon catalyst with substantial OER activity in acid solution by the thermal codecomposition of polyaniline, cobalt salt and cyanamide in nitrogen. Cyanamide and the type of cobalt precursor salt were found to determine the structure, crystallinity, surface area, extent of Co doping and consequently the OER activity of the final carbon catalyst in acid solution. We have also put forward some hypotheses about the active sites that may be useful for guiding further work. PMID:26795393

  1. Phosphate Rock Fertilizer in Acid Soil:Comparing Phosphate Extraction Methods for Measuring Dissolution

    Institute of Scientific and Technical Information of China (English)

    T.S.ANSUMANA-KAWA; WANGGUANGHUO

    1998-01-01

    Three phosphate extraction methods were used to investigate the dissolution,availability and transfo-mation of Kunyang phosphate rock(KPR) in two surface acid soils.Dissolution was determined by measuring the increase in the amounts of soluble and adsorbed inorganic phosphate fractions,and did not differ signifi-cantly among the three methods.Significant correlations were obtained among P fractions got by the three extraction methods.Dissolution continued until the end of the 90-day incubation period.At the end of the period,much of the applied phosphate recovered in both soils were in the Al- and Fe-P or in the hydroxide-and bicarbonate-extractable inorganic P fractions.The dissolution of KPR in the two soils was also similar: increased addition of phosphate rock resulted in decreased dissolution.The similarity in the order and extent of dissolution in the two soils was probably due to the similarity in each soil of several factors that are known to influence phosphate rock dissolution,namely low CEC,pH,P level,and base status;and high clay and free iron and aluminum oxide contents.The results suggested that KPR could be an aternative P source in the soils are not limiting.

  2. MORPHOLOGICAL STUDY ON THE ORIENTED CHITOSAN FILM OBTAINED FROM PRE-SHEARED LIQUID CRYSTALLINE SOLUTION IN DICHLOROACETIC ACID

    Institute of Scientific and Technical Information of China (English)

    Zhong-ming Hu; Li-heng Wu; Da-cheng Wu; Shou-xi Chen

    2001-01-01

    The oriented chitosan films obtained from pre-sheared liquid crystalline chitosan/dichloroacetic acid (DCA)solutions were studied by means of polarized optical microscopy (POM), scanning electron microscopy (SEM), infra-red dichroism technique and wide angle X-ray diffraction (WAXD). The shear induced band texture in the film was found to correspond to the sinusoidal fibrillar microstructure along the shearing direction on the basis of POM and SEM observations.The sinusoidal fibril was found to be lying within the film plane. The model of chitosan molecular orientation in the presheared film with band texture can be established assuming that the main chain orients in the shearing direction and the side group is perpendicular to the shearing direction. The WAXD azimuthal scanning at 2θ = 20° indicates that the (002) plane orients perpendicular to the shearing direction.``

  3. First principles DFT study of weak C-H…O bonds in crystalline amino acids under pressure-alanine

    Science.gov (United States)

    Ramaniah, Lavanya M.; Kamal, C.; Sikka, S. K.

    2013-02-01

    Many crystalline solids containing C-H…O hydrogen bonds display blue shifting of the C-H stretching frequency under pressure. No agreed explanation is available for this. Here, we use first principles density functional theory, to determine the hydrogen atom positions to understand the cause of this blue shift. No neutron diffraction is feasible due to flux limitations for this purpose. As a first case, we have taken up the study of the amino acid, alanine. We find that the C_H_…O bond in it no longer remain isolated under compression as is case at ambient pressure. The hydrogen atom in the bond has now repulsive contacts with other atoms. This results in contraction of the C-H bond length and consequently to blue shifting as is found experimentally.

  4. Thermotropic liquid crystalline polyesters derived from bis-(4-hydroxybenzoyloxy)-2-methyl-1,4-benzene and aliphatic dicarboxylic acid chlorides

    Indian Academy of Sciences (India)

    Khudbudin Mulani; Mohasin Momin; Nitin Ganjave; Nayaku Chavan

    2015-09-01

    A series of thermotropic liquid crystalline polyesters derived from bis-(4-hydroxybenzoyloxy)-2-methyl-1,4-benzene (BHBOMB) and aliphatic dicarboxylic acid chlorides were investigated. All these polyesters were synthesized by interfacial polycondensation method and characterized by differential scanning calorimetry and wide-angle X-ray diffractometer. These polyesters consist of BHBOMB as a mesogenic diol and aliphatic diacid chlorides were used as flexible spacers. The length of oligomethylene units in polymer was varied from the trimethylene to the dodecamethylene groups. The transition temperatures and thermodynamic properties were studied for all these polymers. All these polyesters were soluble in chlorinated solvents such as chloroform, dichloromethane, dichloroethane, etc. More importantly, all these polyesters exhibited very large mesophase stability.

  5. Chemical stability of acid rock drainage treatment sludge and implications for sludge management.

    Science.gov (United States)

    McDonald, Danny M; Webb, John A; Taylor, Jeff

    2006-03-15

    To assess the chemical stability of sludges generated by neutralizing acid rock drainage (ARD) with alkaline reagents, synthetic ARD was treated with hydrated lime (batch and high-density sludge process), limestone, and two proprietary reagents (KB-1 and Bauxsol). The amorphous metal hydroxide sludge produced was leached using deionized water, U.S. EPA methods (toxicity characteristic leaching procedure, synthetic precipitation leaching procedure), and the new strong acid leach test (SALT), which leaches the sludge with a series of sulfuric acid extractant solutions; the pH decreases by approximately 1 pH unit with each test, until the final pH is approximately 2. Sludges precipitated by all reagents had very similar leachabilities except for KB-1 and Bauxsol, which released more aluminum. SALT showed that lowering the pH of the leaching solution mobilized more metals from the sludges. Iron, aluminum, copper, and zinc began to leach at pH 2.5-3, approximately 4.5, approximately 5.5, and 6-6.5, respectively. The leachability of ARD treatment sludges is determined by the final pH of the leachate. A higher neutralization potential (e.g., a greater content of unreacted neutralizing agent) makes sludges inherently more chemically stable. Thus, when ARD or any acidic metalliferous wastewater is treated, a choice must be made between efficient reagent use and resistance to acid attack. PMID:16570625

  6. Effect of plant proteins and crystalline amino acid supplementation on postprandial plasma amino acid profiles and metabolic response in rainbow trout (Oncorhynchus mykiss)

    DEFF Research Database (Denmark)

    Rolland, Marine; Larsen, Bodil Katrine; Holm, Jørgen;

    2015-01-01

    The use of aquafeeds formulated with plant protein sources supplemented with crystalline amino acids (CAAs) is believed to influence amino acid (AA) uptake patterns and AA metabolic fate. Oxygen consumption and ammonia excretion rates were measured in rainbow trout (468.5 +/- A 86.5 g) force fed 0.......75 % of their body mass with a diet based on either (1) fish meal (FM), (2) pea protein concentrate (PPC), or (3) pea protein concentrate supplemented with histidine, lysine, methionine and threonine (PPC+) to mimic FM AA profile. The specific dynamic action and nitrogen quotient (NQ) were calculated for 48 h...... to be caused by an unbalanced dietary AA profile and CAA supplementation, rather than inclusion of plant protein concentrate....

  7. Incorporating Geochemical And Microbial Kinetics In Reactive Transport Models For Generation Of Acid Rock Drainage

    Science.gov (United States)

    Andre, B. J.; Rajaram, H.; Silverstein, J.

    2010-12-01

    Acid mine drainage, AMD, results from the oxidation of metal sulfide minerals (e.g. pyrite), producing ferrous iron and sulfuric acid. Acidophilic autotrophic bacteria such as Acidithiobacillus ferrooxidans and Leptospirillum ferrooxidans obtain energy by oxidizing ferrous iron back to ferric iron, using oxygen as the electron acceptor. Most existing models of AMD do not account for microbial kinetics or iron geochemistry rigorously. Instead they assume that oxygen limitation controls pyrite oxidation and thus focus on oxygen transport. These models have been successfully used for simulating conditions where oxygen availability is a limiting factor (e.g. source prevention by capping), but have not been shown to effectively model acid generation and effluent chemistry under a wider range of conditions. The key reactions, oxidation of pyrite and oxidation of ferrous iron, are both slow kinetic processes. Despite being extensively studied for the last thirty years, there is still not a consensus in the literature about the basic mechanisms, limiting factors or rate expressions for microbially enhanced oxidation of metal sulfides. An indirect leaching mechanism (chemical oxidation of pyrite by ferric iron to produce ferrous iron, with regeneration of ferric iron by microbial oxidation of ferrous iron) is used as the foundation of a conceptual model for microbially enhanced oxidation of pyrite. Using literature data, a rate expression for microbial consumption of ferrous iron is developed that accounts for oxygen, ferrous iron and pH limitation. Reaction rate expressions for oxidation of pyrite and chemical oxidation of ferrous iron are selected from the literature. A completely mixed stirred tank reactor (CSTR) model is implemented coupling the kinetic rate expressions, speciation calculations and flow. The model simulates generation of AMD and effluent chemistry that qualitatively agrees with column reactor and single rock experiments. A one dimensional reaction

  8. Development of grouting technologies for geological disposal of high level waste in Japan (7). Hydrological and chemical change of the groundwater in a pre-grouted crystalline rock after earthquakes

    International Nuclear Information System (INIS)

    The Japan Atomic Energy Agency has conducted 'The project for Grouting Technology Development' under a contract study with the Ministry of Economy, Trade and Industry (METI). As a part of the study, the groundwater chemistry has been monitored for four years after pre-grouting the crystalline rock in the Mizunami underground research laboratory (URL). Measured groundwater pressures were temporarily changed by earthquakes of seismic intensity ≥ 3 and recovered within about one year. Changes to the chemical composition of the groundwater by the earthquakes were not detected and the injected grout material was not significantly damaged. (author)

  9. A series of crystalline solids composed of aminopyridines and succinic, fumaric, and sebacic acids

    Science.gov (United States)

    Sandhu, Bhupinder; Fonari, Marina S.; Sawyer, Kayla; Timofeeva, Tatiana V.

    2013-11-01

    The cocrystallization of five mono- and diaminopyridines, namely 2-aminopyridine (2-AP), 2,3-diaminopyridine (2,3-DAP), 2,6-diaminopyridine (2,6-DAP), 4-aminopyridine (4-AP), and 3,4-diaminopyridine (3,4-DAP), with three dicarboxylic acids, namely, succinic (SUH2), fumaric (FUH2), and sebacic (SEH2) acids resulted in twelve organic salts including two hydrates, (2-HAP)2(SU)(SUH2) 1, (2,3-HDAP)2(SU) 2, (2,3-HDAP)2(SE) 3, (2,6-HDAP)2(FU) 4, (2,6-HDAP)2(SU) 5, (4-HAP)(SUH) 6, (4-HAP)2(FU) 7, (4-HAP)2(SE) 8, (3,4-HDAP)(SUH) 9, (3,4-HDAP)2(SE) 10, (4-HAP)2(FU)ṡ2H2O 11, (4-HAP)2(SU)ṡ2H2O 12. All compounds were characterized by single-crystal X-ray diffraction, IR spectra, and melting points. The proton transfer to the pyridine nitrogen in all compounds, and its location in carboxylic group in adducts with SUH2 (1, 6, and 9) were determined reliably from the low-temperature X-ray experiments. The impact of number and position of amino-groups in the pyridine molecules, as well as the conformational flexibility of the acids, and water inclusion on the final stoichiometries and supramolecular architectures is discussed.

  10. A Comprehensive Study on Lyotropic Liquid-Crystalline Behavior of an Amphiphile in 20 Kinds of Amino Acid Ionic Liquids.

    Science.gov (United States)

    Fujimura, Kanae; Ichikawa, Takahiro; Yoshio, Masafumi; Kato, Takashi; Ohno, Hiroyuki

    2016-02-18

    We examined the self-organization behavior of a designed amphiphilic molecule in 20 kinds of amino acid ionic liquids composed of 1-butyl-3-methylimidazolium cation and natural amino acid anion ([C4mim][AA]). Addition of [C4mim][AA], regardless of their anion species, to the amphiphile provided homogeneous mixtures showing lyotropic liquid-crystalline (LC) behavior. Upon increasing the component ratio of [C4mim][AA] in the mixtures, a successive change of the mesophase patterns from inverted hexagonal columnar, in some case via bicontinuous cubic, to layered phases was observed. By examining the LC properties at various temperatures and component ratios, we constructed lyotropic LC phase diagrams. Interestingly, the appearance of these phase diagrams is greatly different according to the selection of [AA]. Through comparison, we found that the self-organization behavior of an amphiphile in ionic liquids can be tuned by controlling their ability to form hydrogen-bond, van der Waals, and π-π interactions.

  11. Hydrogeology and simulation of ground-water flow in the thick regolith-fractured crystalline rock aquifer system of Indian Creek basin, North Carolina

    Science.gov (United States)

    Daniel, Charles C.; Smith, Douglas G.; Eimers, Jo Leslie

    1997-01-01

    The Indian Creek Basin in the southwestern Piedmont of North Carolina is one of five type areas studied as part of the Appalachian Valleys-Piedmont Regional Aquifer-System analysis. Detailed studies of selected type areas were used to quantify ground-water flow characteristics in various conceptual hydrogeologic terranes. The conceptual hydrogeologic terranes are considered representative of ground-water conditions beneath large areas of the three physiographic provinces--Valley and Ridge, Blue Ridge, and Piedmont--that compose the Appalachian Valleys-Piedmont Regional Aquifer-System Analysis area. The Appalachian Valleys-Piedmont Regional Aquifer-System Analysis study area extends over approximately 142,000 square miles in 11 states and the District of Columbia in the Appalachian highlands of the Eastern United States. The Indian Creek type area is typical of ground-water conditions in a single hydrogeologic terrane that underlies perhaps as much as 40 percent of the Piedmont physiographic province. The hydrogeologic terrane of the Indian Creek model area is one of massive and foliated crystalline rocks mantled by thick regolith. The area lies almost entirely within the Inner Piedmont geologic belt. Five hydrogeologic units occupy major portions of the model area, but statistical tests on well yields, specific capacities, and other hydrologic characteristics show that the five hydrogeologic units can be treated as one unit for purposes of modeling ground-water flow. The 146-square-mile Indian Creek model area includes the Indian Creek Basin, which has a surface drainage area of about 69 square miles. The Indian Creek Basin lies in parts of Catawba, Lincoln, and Gaston Counties, North Carolina. The larger model area is based on boundary conditions established for digital simulation of ground-water flow within the smaller Indian Creek Basin. The ground-water flow model of the Indian Creek Basin is based on the U.S. Geological Survey?s modular finite

  12. A Density Functional Tight Binding Study of Acetic Acid Adsorption on Crystalline and Amorphous Surfaces of Titania

    Directory of Open Access Journals (Sweden)

    Sergei Manzhos

    2015-02-01

    Full Text Available We present a comparative density functional tight binding study of an organic molecule attachment to TiO2 via a carboxylic group, with the example of acetic acid. For the first time, binding to low-energy surfaces of crystalline anatase (101, rutile (110 and (B-TiO2 (001, as well as to the surface of amorphous (a- TiO2 is compared with the same computational setup. On all surfaces, bidentate configurations are identified as providing the strongest adsorption energy, Eads = −1.93, −2.49 and −1.09 eV for anatase, rutile and (B-TiO2, respectively. For monodentate configurations, the strongest Eads = −1.06, −1.11 and −0.86 eV for anatase, rutile and (B-TiO2, respectively. Multiple monodentate and bidentate configurations are identified on a-TiO2 with a distribution of adsorption energies and with the lowest energy configuration having stronger bonding than that of the crystalline counterparts, with Eads up to −4.92 eV for bidentate and −1.83 eV for monodentate adsorption. Amorphous TiO2 can therefore be used to achieve strong anchoring of organic molecules, such as dyes, that bind via a -COOH group. While the presence of the surface leads to a contraction of the band gap vs. the bulk, molecular adsorption caused no appreciable effect on the band structure around the gap in any of the systems.

  13. Magmatic and petrologic evolution of the mesozvic vulcanic acid rocks from Piraju-Ourinhos region (SP-PR)

    International Nuclear Information System (INIS)

    This work presents the result of geological, petrological and geochemical studies, on the volcanic rocks from Piraju-Ourinhos region, SP, with special emphasis on the rocks. A geological mapping was carried out by using images from Landsat satellite. Petrographic and chemical analyses have defined a suite represented by basic lithotype - tholeutic andesibasalt - with high TiO2, rich in incompable elements - mainly Sr, Zr, La, Ce, and Ba - and by acid lithotype - rhyolite - rhyodacite. k-Ar ages are determined in feldspar concentrated, and indicate an age of 133+- 4m,y, for the volcanic acid rocks. Determinations of Sr isotopes. In order to explain the genesis of Chapeco type acid magnas quantitative models were tested using both fractional Crystallization

  14. Biochar enhances Aspergillus niger rock phosphate solubilization by increasing organic acid production and alleviating fluoride toxicity.

    Science.gov (United States)

    Mendes, Gilberto de Oliveira; Zafra, David Lopez; Vassilev, Nikolay Bojkov; Silva, Ivo Ribeiro; Ribeiro, José Ivo; Costa, Maurício Dutra

    2014-05-01

    During fungal rock phosphate (RP) solubilization, a significant quantity of fluoride (F(-)) is released together with phosphorus (P), strongly inhibiting the process. In the present study, the effect of two F(-) adsorbents [activated alumina (Al2O3) and biochar] on RP solubilization by Aspergillus niger was examined. Al2O3 adsorbed part of the F(-) released but also adsorbed soluble P, which makes it inappropriate for microbial RP solubilization systems. In contrast, biochar adsorbed only F(-) while enhancing phosphate solubilization 3-fold, leading to the accumulation of up to 160 mg of P per liter. By comparing the values of F(-) measured in solution at the end of incubation and those from a predictive model, it was estimated that up to 19 mg of F(-) per liter can be removed from solution by biochar when added at 3 g liter(-1) to the culture medium. Thus, biochar acted as an F(-) sink during RP solubilization and led to an F(-) concentration in solution that was less inhibitory to the process. In the presence of biochar, A. niger produced larger amounts of citric, gluconic, and oxalic acids, whether RP was present or not. Our results show that biochar enhances RP solubilization through two interrelated processes: partial removal of the released F(-) and increased organic acid production. Given the importance of organic acids for P solubilization and that most of the RPs contain high concentrations of F(-), the proposed solubilization system offers an important technological improvement for the microbial production of soluble P fertilizers from RP.

  15. Environmental risk assessment of acid rock drainage under uncertainty: The probability bounds and PHREEQC approach.

    Science.gov (United States)

    Betrie, Getnet D; Sadiq, Rehan; Nichol, Craig; Morin, Kevin A; Tesfamariam, Solomon

    2016-01-15

    Acid rock drainage (ARD) is a major environmental problem that poses significant environmental risks during and after mining activities. A new methodology for environmental risk assessment based on probability bounds and a geochemical speciation model (PHREEQC) is presented. The methodology provides conservative and non-conservative ways of estimating risk of heavy metals posed to selected endpoints probabilistically, while propagating data and parameter uncertainties throughout the risk assessment steps. The methodology is demonstrated at a minesite located in British Columbia, Canada. The result of the methodology for the case study minesite shows the fate-and-transport of heavy metals is well simulated in the mine environment. In addition, the results of risk characterization for the case study show that there is risk due to transport of heavy metals into the environment.

  16. Pharmacokinetics of a long-acting ceftiofur formulation (ceftiofur crystalline free acid) in the ball python (Python regius).

    Science.gov (United States)

    Adkesson, Michael J; Fernandez-Varon, Emilio; Cox, Sherry; Martín-Jiménez, Tomás

    2011-09-01

    The objective of this study was to determine the pharmacokinetics of a long-acting formulation of ceftiofur crystalline-free acid (CCFA) following intramuscular injection in ball pythons (Python regius). Six adult ball pythons received an injection of CCFA (15 mg/kg) in the epaxial muscles. Blood samples were collected by cardiocentesis immediately prior to and at 0.5, 1, 2, 4, 8, 12, 18, 24, 48, 72, 96, 144, 192, 240, 288, 384, 480, 576, 720, and 864 hr after CCFA administration. Plasma ceftiofur concentrations were determined by high-performance liquid chromatography. A noncompartmental pharmacokinetic analysis was applied to the data. Maximum plasma concentration (Cmax) was 7.096 +/- 1.95 microg/ml and occurred at (Tmax) 2.17 +/- 0.98 hr. The area under the curve (0 to infinity) for ceftiofur was 74.59 +/- 13.05 microg x h/ml and the elimination half-life associated with the terminal slope of the concentration-time curve was 64.31 +/- 14.2 hr. Mean residence time (0 to infinity) was 46.85 +/- 13.53 hr. CCFA at 15 mg/kg was well tolerated in all the pythons. Minimum inhibitory concentration (MIC) data for bacterial isolates from snakes are not well established. For MIC values of python. For MICs > or =0.5 microg/ml, more frequent dosing or a higher dosage may be required.

  17. Trace metal mobilization from oil sands froth treatment thickened tailings exhibiting acid rock drainage.

    Science.gov (United States)

    Kuznetsova, Alsu; Kuznetsov, Petr; Foght, Julia M; Siddique, Tariq

    2016-11-15

    Froth treatment thickened tailings (TT) are a waste product of bitumen extraction from surface-mined oil sands ores. When incubated in a laboratory under simulated moist oxic environmental conditions for ~450d, two different types of TT (TT1 and TT2) exhibited the potential to generate acid rock drainage (ARD) by producing acid leachate after 250 and 50d, respectively. We report here the release of toxic metals from TT via ARD, which could pose an environmental threat if oil sands TT deposits are not properly managed. Trace metal concentrations in leachate samples collected periodically revealed that Mn and Sr were released immediately even before the onset of ARD. Spikes in Co and Ni concentrations were observed both pre-ARD and during active ARD, particularly in TT1. For most elements measured (Fe, Cr, V, As, Cu, Pb, Zn, Cd, and Se), leaching was associated with ARD production. Though equivalent acidification (pH2) was achieved in leachate from both TT types, greater metal release was observed from TT2 where concentrations reached 10,000ppb for Ni, 5000ppb for Co, 3000ppb for As, 2000ppb for V, and 1000ppb for Cr. Generally, metal concentrations decreased in leachate with time during ARD and became negligible by the end of incubation (~450d) despite appreciable metals remaining in the leached TT. These results suggest that using TT for land reclamation purposes or surface deposition for volume reduction may unfavorably impact the environment, and warrants application of appropriate strategies for management of pyrite-enriched oil sands tailings streams. PMID:27443453

  18. Characterization of Green Liquor Dregs, Potentially Useful for Prevention of the Formation of Acid Rock Drainage

    Directory of Open Access Journals (Sweden)

    Maria Mäkitalo

    2014-04-01

    Full Text Available Using alternative materials such as residual products from other industries to mitigate the negative effects of acid rock drainage would simultaneously solve two environmental problems. The main residual product still landfilled by sulphate paper mills is the alkaline material green liquor dregs (GLD. A physical, mineralogical and chemical characterization of four batches of GLD was carried out to evaluate the potential to use it as a sealing layer in the construction of dry covers on sulphide-bearing mine waste. GLD has relatively low hydraulic conductivity (10−8 to 10−9 m/s, a high water retention capacity (WRC and small particle size. Whilst the chemical and mineralogical composition varied between the different batches, these variations were not reflected in properties such as hydraulic conductivity and WRC. Due to relatively low trace element concentrations, leaching of contaminants from the GLD is not a concern for the environment. However, GLD is a sticky material, difficult to apply on mine waste deposits and the shear strength is insufficient for engineering applications. Therefore, improving the mechanical properties is necessary. In addition, GLD has a high buffering capacity indicating that it could act as an alkaline barrier. Once engineering technicalities have been overcome, the long-term effectiveness of GLD should be studied, especially the effect of aging and how the sealing layer would be engineered in respect to topography and climatic conditions.

  19. Algae as an electron donor promoting sulfate reduction for the bioremediation of acid rock drainage.

    Science.gov (United States)

    Ayala-Parra, Pedro; Sierra-Alvarez, Reyes; Field, Jim A

    2016-11-01

    This study assessed bioremediation of acid rock drainage in simulated permeable reactive barriers (PRB) using algae, Chlorella sorokiniana, as the sole electron donor for sulfate-reducing bacteria. Lipid extracted algae (LEA), the residues of biodiesel production, were compared with whole cell algae (WCA) as an electron donor to promote sulfate-reducing activity. Inoculated columns containing anaerobic granular sludge were fed a synthetic medium containing H2SO4 and Cu(2+). Sulfate, sulfide, Cu(2+) and pH were monitored throughout the experiment of 123d. Cu recovered in the column packing at the end of the experiment was evaluated using sequential extraction. Both WCA and LEA promoted 80% of sulfate removal (12.7mg SO4(2-) d(-1)) enabling near complete Cu removal (>99.5%) and alkalinity generation raising the effluent pH to 6.5. No noteworthy sulfate reduction, alkalinity formation and Cu(2+) removal were observed in the endogenous control. In algae amended-columns, Cu(2+) was precipitated with biogenic H2S produced by sulfate reduction. Formation of CuS was evidenced by sequential extraction and X-ray diffraction. LEA and WCA provided similar levels of electron donor based on the COD balance. The results demonstrate an innovative passive remediation system using residual algae biomass from the biodiesel industry. PMID:27318730

  20. The Effect of 4-Octyldecyloxybenzoic Acid on Liquid-Crystalline Polyurethane Composites with Triple-Shape Memory and Self-Healing Properties

    Directory of Open Access Journals (Sweden)

    Jianfeng Ban

    2016-09-01

    Full Text Available To better understand shape memory materials and self-healing materials, a new series of liquid-crystalline shape memory polyurethane (LC-SMPU composites, named SMPU-OOBAm, were successfully prepared by incorporating 4-octyldecyloxybenzoic acid (OOBA into the PEG-based SMPU. The effect of OOBA on the structure, morphology, and properties of the material has been carefully investigated. The results demonstrate that SMPU-OOBAm has liquid crystalline properties, triple-shape memory properties, and self-healing properties. The incorporated OOBA promotes the crystallizability of both soft and hard segments of SMPU, and the crystallization rate of the hard segment of SMPU decreases when the OOBA-content increases. Additionally, the SMPU-OOBAm forms a two-phase separated structure (SMPU phase and OOBA phase, and it shows two-step modulus changes upon heating. Therefore, the SMPU-OOBAm exhibits triple-shape memory behavior, and the shape recovery ratio decreases with an increase in the OOBA content. Finally, SMPU-OOBAm exhibits self-healing properties. The new mechanism can be ascribed to the heating-induced “bleeding” of OOBA in the liquid crystalline state and the subsequent re-crystallization upon cooling. This successful combination of liquid crystalline properties, triple-shape memory properties, and self-healing properties make the SMPU-OOBAm composites ideal for many promising applications in smart optical devices, smart electronic devices, and smart sensors.

  1. Water - rock interaction in different rock environments

    International Nuclear Information System (INIS)

    The study assesses the groundwater geochemistry and geological environment of 44 study sites for radioactive waste disposal. Initially, the study sites were divided by rock type into 5 groups: (1) acid - intermediate rocks, (2) mafic - ultramafic rocks, (3) gabbros, amphibolites and gneisses that contain calc-silicate (skarn) rocks, (4) carbonates and (5) sandstones. Separate assessments are made of acid - intermediate plutonic rocks and of a subgroup that comprises migmatites, granite and mica gneiss. These all belong to the group of acid - intermediate rocks. Within the mafic -ultramafic rock group, a subgroup that comprises mafic - ultramafic plutonic rocks, serpentinites, mafic - ultramafic volcanic rocks and volcanic - sedimentary schists is also evaluated separately. Bedrock groundwaters are classified by their concentration of total dissolved solids as fresh, brackish, saline, strongly saline and brine-class groundwaters. (75 refs., 24 figs., 3 tabs.)

  2. Radiological, chemical and morphological characterizations of phosphate rock and phosphogypsum from phosphoric acid factories in SW Spain

    Energy Technology Data Exchange (ETDEWEB)

    Renteria-Villalobos, Marusia, E-mail: marusia@us.es [Applied Nuclear Physics Group, University of Seville, ETS Arquitectura, Departamento de Fisica Aplicada, Avda. Reina Mercedes s/n, 41012 Seville (Spain); Advanced Materials Research Center (CIMAV), Miguel de Cervantes 120, 31109 Chihuahua (Mexico); Vioque, Ignacio, E-mail: ivioque@us.es [Applied Nuclear Physics Group, University of Seville, ETS Arquitectura, Departamento de Fisica Aplicada, Avda. Reina Mercedes s/n, 41012 Seville (Spain); Mantero, Juan, E-mail: manter@us.es [Applied Nuclear Physics Group, University of Seville, ETS Arquitectura, Departamento de Fisica Aplicada, Avda. Reina Mercedes s/n, 41012 Seville (Spain); Manjon, Guillermo, E-mail: manjon@us.es [Applied Nuclear Physics Group, University of Seville, ETS Arquitectura, Departamento de Fisica Aplicada, Avda. Reina Mercedes s/n, 41012 Seville (Spain)

    2010-09-15

    In this work, radiological, chemical, and also morphological characterization was performed in phosphate rock and phosphogypsum samples, in order to understand the behavior of toxic elements. Characterization was carried out using X-ray diffraction (XRD), X-ray fluorescence (XRF), gamma spectrometry and scanning electron microscopy with energy-dispersive X-ray analysis (SEM-EDX). Our results show that the phosphate rock was mainly composed of fluorapatite, calcite, perovskite, quartz, magnetite, pyrite and kaolinite, whereas phosphogypsum only exhibited dihydrated calcium sulfate. The activity concentration of U-series radioisotopes in phosphate rock was around 1640 Bq/kg. {sup 226}Ra and {sup 210}Pb tend to be distributed into phosphogypsum by up to 80%, whereas the fraction of U-isotopes is 10%. The most abundant trace elements in phosphate rock were Sr, Cr, V, Zn, Y, Ni and Ba. Some elements, such as Ba, Cd, Cu, La, Pb, Se, Sr, Th and Y, were enriched in the phosphogypsum. This enrichment may be attributed to an additional input associated to the sulfuric acid used for the phosphoric acid production. Furthermore, results from SEM-EDX demonstrated that toxic elements are not distributed homogeneously into phosphogypsum. Most of these elements are concentrated in particles <20 {mu}m of high porosity, and could be easily mobilized by leaching and/or erosion.

  3. Radiological, chemical and morphological characterizations of phosphate rock and phosphogypsum from phosphoric acid factories in SW Spain

    International Nuclear Information System (INIS)

    In this work, radiological, chemical, and also morphological characterization was performed in phosphate rock and phosphogypsum samples, in order to understand the behavior of toxic elements. Characterization was carried out using X-ray diffraction (XRD), X-ray fluorescence (XRF), gamma spectrometry and scanning electron microscopy with energy-dispersive X-ray analysis (SEM-EDX). Our results show that the phosphate rock was mainly composed of fluorapatite, calcite, perovskite, quartz, magnetite, pyrite and kaolinite, whereas phosphogypsum only exhibited dihydrated calcium sulfate. The activity concentration of U-series radioisotopes in phosphate rock was around 1640 Bq/kg. 226Ra and 210Pb tend to be distributed into phosphogypsum by up to 80%, whereas the fraction of U-isotopes is 10%. The most abundant trace elements in phosphate rock were Sr, Cr, V, Zn, Y, Ni and Ba. Some elements, such as Ba, Cd, Cu, La, Pb, Se, Sr, Th and Y, were enriched in the phosphogypsum. This enrichment may be attributed to an additional input associated to the sulfuric acid used for the phosphoric acid production. Furthermore, results from SEM-EDX demonstrated that toxic elements are not distributed homogeneously into phosphogypsum. Most of these elements are concentrated in particles <20 μm of high porosity, and could be easily mobilized by leaching and/or erosion.

  4. Exploring plant factors for increasing phosphorus utilization from rock phosphates and native soil phosphates in acidic soils

    International Nuclear Information System (INIS)

    Six plant species with contrasting capacity in utilizing rock phosphates were compared with regard to their responses to phosphorus starvation in hydroponic cultures. Radish, buckwheat and oil rapeseed are known to have strong ability to use rock phosphates while ryegrass, wheat and sesbania are less efficient. Whereas other plants acidified their culture solution under P starvation (-P), radish plants make alkaline the solution. When neutralizing the pH of the solutions cultured with plants under either -P or + P conditions, solutions with P starved buckwheat, rapeseed, and radish had a higher ability to solubilize Al and Fe phosphates than did those cultured with sesbania, ryegrass and wheat. Characterization of organic ligands in the solutions identified that citrate and malate were the major organic anions exuded by rapeseed and radish. Besides citrate and malate, buckwheat exuded a large amount of tartrate under P starvation. In contrast, ryegrass, wheat and sesbania secreted only a limited amount of oxalic acid, regardless of P status. Changes in activities of phosphoenolpyruvate carboxylase, acid phosphatase, and nitrate reductase in these plants were also compared under P- sufficient or -deficient conditions. The results indicated that plant ability to use rock phosphates or soil phosphates is closely related to their responses toward P starvation. The diversity of P starvation responses was discussed in the context of co-evolution between plants and their environment. Approaches to use plant factors to enhance the effectiveness of rock phosphates were also discussed. (author)

  5. Analysis of rocking curve width and bound exciton linewidth of MOCVD grown CdTe layers in relation with substrate type and crystalline orientation

    Science.gov (United States)

    Tromson-Carli, A.; Svob, L.; Marfaing, Y.; Druilhe, R.; Desjonqueres, F.; Triboulet, R.

    1991-12-01

    X-ray double diffraction and photoluminescence experiments were performed on a series of CdTe layers grown by MOVPE on CdTe, CdZnTe and GaAs substrates. Some correlation appears between the measured rocking curve widths and impurity-bound exciton linewidth. To analyze these results, a model relating the exciton linewidth to the average strain induced by an array of random dislocations has been developed. It appears that X-ray diffraction is also sensitive to non-random dislocation configurations which do not affect luminescence linewidth.

  6. A methodology to constrain the parameters of a hydrogeological discrete fracture network model for sparsely fractured crystalline rock, exemplified by data from the proposed high-level nuclear waste repository site at Forsmark, Sweden

    Science.gov (United States)

    Follin, Sven; Hartley, Lee; Rhén, Ingvar; Jackson, Peter; Joyce, Steven; Roberts, David; Swift, Ben

    2014-03-01

    The large-scale geological structure of the crystalline rock at the proposed high-level nuclear waste repository site at Forsmark, Sweden, has been classified in terms of deformation zones of elevated fracture frequency. The rock between deformation zones was divided into fracture domains according to fracture frequency. A methodology to constrain the geometric and hydraulic parameters that define a discrete fracture network (DFN) model for each fracture domain is presented. The methodology is based on flow logging and down-hole imaging in cored boreholes in combination with DFN realizations, fracture connectivity analysis and pumping test simulations. The simulations suggest that a good match could be obtained for a power law size distribution where the value of the location parameter equals the borehole radius but with different values for the shape parameter, depending on fracture domain and fracture set. Fractures around 10-100 m in size are the ones that typically form the connected network, giving inflows in the simulations. The report also addresses the issue of up-scaling of DFN properties to equivalent continuous porous medium (ECPM) bulk flow properties. Comparisons with double-packer injection tests provide confidence that the derived DFN formulation of detailed flows within individual fractures is also suited to simulating mean bulk flow properties and their spatial variability.

  7. Long term field evaluation of phosphate rock and superphosphate in acid soils of Hungary; Incubation and pot experiments

    International Nuclear Information System (INIS)

    A series of experiments was conducted to compare the agronomic effectiveness of phosphate rock (from Algeria) and of single superphosphate (from Russia, Kola) on a moderately acidic pseudogley brown forest soil (Szentgyoergyvoelgy) and on a slightly acidic chernozem brown forest soil (Kompolt). Dynamics of water-soluble and ammonium lactate-soluble P-contents (AL-P) and soil pH-H2O changes were studied in a half-year long incubation experiment. A follow-up pot experiment with the same soils was carried out with winter rape as test plants. Both experiments were set up with similar P fertilizer sources and P rates (100, 200, and 400 mg mineral acid soluble P2O5 per kg soil). At the beginning of incubation experiment, the water-soluble P content of the pseudogley brown forest soil was influenced by both the sources of P and the experimental conditions. The water-soluble P content decreased with time. After the 15th to 20th day of incubation, when the fast binding process of the water-soluble P ended, the effects of the P forms decreased. In this stage, the effects of environmental conditions depended on the form of the P fertilizer. The water-soluble P content of the phosphate rock-treated samples was affected to a great extent by soil water content, while the incubation temperature had a greater effect in soils treated with superphosphate. The AL-P content of soils was increased similarly by addition of equal rates of phosphate rock and super-phosphate at the beginning of incubation. The AL-P content of phosphate rock-treated soils was higher throughout the incubation period than of the superphosphate-treated soils -treated. Temperature had a greater effect on the AL-P content of soils than soil water content. As the AL-extraction may dissolve a substantial amount of the undecomposed phosphate rock, this method is not applicable to soil testing of available P forms from phosphate rock-treated soils. Initial soil pH decreased on average by 0.5 units in the

  8. Long term field evaluation of phosphate rock and superphosphate in acid soils of Hungary; Incubation and pot experiments

    International Nuclear Information System (INIS)

    A series of experiments was conducted to compare the agronomic effectiveness of phosphate rock (from Algeria) and of single superphosphate (from Russia, Kola) on a moderately acidic pseudogley brown forest soil (Szentgyoergyvoelgy) and on a slightly acidic chernozem brown forest soil (Kompolt). Dynamics of water-soluble and ammonium lactate-soluble P-contents (AL-P) and soil pH-H2O changes were studied in a half-year long incubation experiment. A follow-up pot experiment with the same soils was carried out with winter rape as test plants. Both experiments were set up with similar P fertilizer sources and P rates (100, 200, and 400 mg mineral acid soluble P2O5 per kg soil). At the beginning of incubation experiment, the water-soluble P content of the pseudogley brown forest soil was influenced by both the sources of P and the experimental conditions. The water-soluble P content decreased with time. After the 15th to 20th day of incubation, when the fast binding process of the water-soluble P ended, the effects of the P forms decreased. In this stage, the effects of environmental conditions depended on the form of the P fertilizer. The water-soluble P content of the phosphate rock-treated samples was affected to a great extent by soil water content, while the incubation temperature had a greater effect in soils treated with superphosphate. The AL-P content of soils was increased similarly by addition of equal rates of phosphate rock and super-phosphate at the beginning of incubation. The AL-P content of phosphate rock-treated soils was higher throughout the incubation period than of the superphosphate-treated soils -treated. Temperature had a greater effect on the AL-P content of soils than soil water content. As the AL-extraction may dissolve a substantial amount of the undecomposed phosphate rock, this method is not applicable to soil testing of available P forms from phosphate rock-treated soils. Initial soil pH decreased on average by 0.5 units in the

  9. Hydrothermal synthesis of highly crystalline RuS2 nanoparticles as cathodic catalysts in the methanol fuel cell and hydrochloric acid electrolysis

    International Nuclear Information System (INIS)

    Highlights: • Highly crystalline RuS2 nanoparticles have been first synthesized by a “one-step” hydrothermal method. • The product presents a pure cubic phase of stoichiometric ratio RuS2 with average particle size of 14.8 nm. • RuS2 nanoparticles were used as cathodic catalysts in methanol fuel cell and hydrochloric acid electrolysis. • The catalyst outperforms commercial Pt/C in methanol tolerance and stability towards Cl−. - Abstract: Highly crystalline ruthenium sulfide (RuS2) nanoparticles have been first synthesized by a “one-step” hydrothermal method at 400 °C, using ruthenium chloride and thiourea as reactants. The products were characterized by powder X-ray diffraction (XRD), scanning electron microscopy/energy disperse spectroscopy (SEM/EDS), thermo gravimetric-differential thermal analyze (TG-DTA), transmission electron microscopy equipped with selected area electron diffraction (TEM/SAED). Fourier transform infrared spectra (IR), and X-ray photoelectron spectroscopy (XPS). XRD result illustrates that the highly crystalline product presents a pure cubic phase of stoichiometric ratio RuS2 and the average particle size is 14.8 nm. SEM and TEM images display the products have irregular shape of 6–25 nm. XPS analyst indicates that the sulfur exists in the form of S22−. Cyclic voltammetry (CV), rotating disk electrode (RDE), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS) measurements are conducted to evaluate the electrocatalytic activity and stability of the highly crystalline RuS2 nanoparticles in oxygen reduction reaction (ORR) for methanol fuel cell and hydrochloric acid electrolysis. The results illustrate that RuS2 is active towards oxygen reduction reaction. Although the activity of RuS2 is lower than that of Pt/C, the RuS2 catalyst outperforms commercial Pt/C in methanol tolerance and stability towards Cl−

  10. Phosphate Stability in Diagenetic Fluids Constrains the Acidic Alteration Model for Lower Mt. Sharp Sedimentary Rocks in Gale Crater, Mars

    Science.gov (United States)

    Berger, J. A.; Schmidt, M. E.; Izawa, M. R. M.; Gellert, R.; Ming, D. W.; Rampe, E. B.; VanBommel, S. J.; McAdam, A. C.

    2016-01-01

    The Mars rover Curiosity has encountered silica-enriched bedrock (as strata and as veins and associated halos of alteration) in the largely basaltic Murray Fm. of Mt. Sharp in Gale Crater. Alpha Particle X-ray Spectrometer (APXS) investigations of the Murray Fm. revealed decreasing Mg, Ca, Mn, Fe, and Al, and higher S, as silica increased (Fig. 1). A positive correlation between SiO2 and TiO2 (up to 74.4 and 1.7 wt %, respectively) suggests that these two insoluble elements were retained while acidic fluids leached more soluble elements. Other evidence also supports a silica-retaining, acidic alteration model for the Murray Fm., including low trace element abundances consistent with leaching, and the presence of opaline silica and jarosite determined by CheMin. Phosphate stability is a key component of this model because PO4 3- is typically soluble in acidic water and is likely a mobile ion in diagenetic fluids (pH less than 5). However, the Murray rocks are not leached of P; they have variable P2O5 (Fig. 1) ranging from average Mars (0.9 wt%) up to the highest values in Gale Crater (2.5 wt%). Here we evaluate APXS measurements of Murray Fm. bedrock and veins with respect to phosphate stability in acidic fluids as a test of the acidic alteration model for the Lower Mt. Sharp rocks.

  11. The International intraval project. Phase 1 case 4: flow and tracer experiment in crystalline rock based on the stripa 3-D experiment

    International Nuclear Information System (INIS)

    The INTRAVAL test case 4 is based upon the Stripa 3-D experiment performed at the Stripa mine in central Sweden. This 3-D experiment provides a unique opportunity to examine tracer transport through a three dimensional block of granite above the drift, containing the boreholes. This report summarizes the modelling and model validation programmes of the four project teams who have analyzed the available data as part of INTRAVAL. The individual modeling approaches taken provide a range of analyses that are both complementary and stimulating. The experiment was over a large spatial scale and enabled the collection of data on tracer transport through a three dimensional block of fractured rock. The underlying fracture geometry was also investigated against the background of the observed flow rates prior to the selection of injection sites. The subsequent tracer breakthrough data was highly heterogeneous and represented a formidable challenge to the validity of existing conceptual and mathematical models for tracer migration and dispersal within fracture rock systems. Four project teams employed four diverse approaches: numerical simulations/synthesis; uniform continuum models investigating dispersive effects due to a range of possible processes; models based upon the variable aperture concept analysing the dispersive effects of local fluctuations in fracture and flow path geometry; and a fractal model analyzing the overall connectivity and geometry of the flow path network. Importantly, the Stripa data was perceived to be representative of flow through granite and all of the teams validated and discussed: - highly channeled flow path models; - the role of local channel to channel variations of transmissivities in providing a dispersive mechanisms; or both. 30 refs., 17 figs., 10 tabs

  12. Grimsel test site investigation Phase IV. The Nagra-JAEA in situ study of safety relevant radionuclide retardation in fractured crystalline rock. III: The RRP project final report

    International Nuclear Information System (INIS)

    To enhance the understanding of radionuclide transport/retardation in fractured rock, Nagra and JAEA worked together for nearly 15 years on a Radionuclide Migration Programme at Nagra's Grimsel Test Site (GTS). This started with the Migration Experiment (MI) project and moved on to Excavation Project (EP) and the Connected Porosity project. Traditionally, studies such as MI produce data for the overall flow system 'seen' by the radionuclides. These data are then modelled to produce a set of best fit bulk or average values for the transport/retardation parameters. However, the model values obtained may not be a unique solution and no detailed information is obtained about where the retardation actually takes place. The extrapolation from one flow system to another where properties are different can only be done if the underlying processes are well understood. This is a key issue as the geosphere around a radioactive waste repository will not be exhaustively explored due to the necessity to maintain favourable characteristics in as unperturbed a state as possible. Hence, it is essential that extrapolations from similar sites, where such restrictions do not apply, can be justified by a thorough understanding of the factors influencing in situ radionuclide transport and retardation. As part of this strategy, Nagra and JAEA proposed another experiment which took a step further than MI-EP. In the Nagra-JAEA EP radionuclide cocktails of strongly sorbing radionuclides with complex chemistries were injected into a water-conducting shear zone, followed by the excavation of the traced part of the shear zone (approximately two tonnes of rock). The development, improvement and testing of new methodologies and techniques was required owing to the complexity of the project and to the scale of the in situ experiment. The extensive efforts undertaken in order to guarantee a successful experiment required a series of laboratory and field tests at the GTS, the latter wherever

  13. Characterisation and modelling of mixing processes in groundwaters of a potential geological repository for nuclear wastes in crystalline rocks of Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Gómez, Javier B., E-mail: jgomez@unizar.es; Gimeno, María J., E-mail: mjgimeno@unizar.es; Auqué, Luis F., E-mail: lauque@unizar.es; Acero, Patricia, E-mail: patriace@unizar.es

    2014-01-01

    This paper presents the mixing modelling results for the hydrogeochemical characterisation of groundwaters in the Laxemar area (Sweden). This area is one of the two sites that have been investigated, under the financial patronage of the Swedish Nuclear Waste and Management Co. (SKB), as possible candidates for hosting the proposed repository for the long-term storage of spent nuclear fuel. The classical geochemical modelling, interpreted in the light of the palaeohydrogeological history of the system, has shown that the driving process in the geochemical evolution of this groundwater system is the mixing between four end-member waters: a deep and old saline water, a glacial meltwater, an old marine water, and a meteoric water. In this paper we put the focus on mixing and its effects on the final chemical composition of the groundwaters using a comprehensive methodology that combines principal component analysis with mass balance calculations. This methodology allows us to test several combinations of end member waters and several combinations of compositional variables in order to find optimal solutions in terms of mixing proportions. We have applied this methodology to a dataset of 287 groundwater samples from the Laxemar area collected and analysed by SKB. The best model found uses four conservative elements (Cl, Br, oxygen-18 and deuterium), and computes mixing proportions with respect to three end member waters (saline, glacial and meteoric). Once the first order effect of mixing has been taken into account, water–rock interaction can be used to explain the remaining variability. In this way, the chemistry of each water sample can be obtained by using the mixing proportions for the conservative elements, only affected by mixing, or combining the mixing proportions and the chemical reactions for the non-conservative elements in the system, establishing the basis for predictive calculations. - Highlights: • Laxemar (Sweden) groundwater is the combined result

  14. Acid dissolution of soils and rocks for the determination of boron by inductively coupled plasma atomic emission spectrometry

    International Nuclear Information System (INIS)

    The boron concentration in rocks, soils and standard reference materials was determined using hydrofluoric acid-aqua regia dissolution followed by inductively coupled plasma atomic emission spectrometry (ICP-AES) using the B 1 249.773 -nm line, corrected for spectral interference by iron. An excess of fluoride was complexed with aluminium to release boron from the stable fluoroborate ion and to protect the borosilicate and quartz components of the instrument. Boron was not lost by volatilisation during volume reduction. Soil and rock boron values determined using the recommended dissolution procedures were comparable to those obtained using the accepted sodium carbonate fusion procedure and by d.c. arc emission spectrophotometry, and those for standard reference materials showed good agreement and precision with the literature values. (author)

  15. DECOVALEX III/BENCHPAR PROJECTS. The Thermal-Hydro-Mechanical Responses to a Glacial Cycle and their Potential Implications for Deep Geological Disposal of Nuclear Fuel Waste in a Fractured Crystalline Rock Mass. Report of BMT3/WP4

    Energy Technology Data Exchange (ETDEWEB)

    Chan, T.; Stanchell, F.W. [Atomic Energy of Canada Ltd, Toronto (Canada); Christiansson, R. [Swedish Nuclear Fuel and Waste Management Co., Figeholm (Sweden); Boulton, G.S. [Univ. of Edinburgh (United Kingdom). School of GeoSciences; Eriksson, L.O.; Vistrand, P.; Wallroth, T. [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Geology; Hartikainen, J. [Helsinki Univ. of Technology (Finland). Inst. of Mathematics; Jensen, M.R. [0ntario Power Generation, Toronto (Canada); Mas lvars, D. [Royal Inst. of Technology, Stockholm (Sweden). Land and Water Resources engineering

    2005-02-15

    A number of studies related to past and on-going deep repository performance assessments have identified glaciation/deglaciation as major future events in the next few hundred thousand years capable of causing significant impact on the long term performance of the repository system. Benchmark Test 3 (BMT3) of the international DECOVALEX III project has been designed to provide an illustrative example that explores the mechanical and hydraulic response of a fractured crystalline rock mass to a period of glaciation. The primary purpose of this numerical study is to investigate whether transient events associated with a glacial cycle could significantly influence the performance of a deep geological repository in a crystalline shield setting. A conceptual site-scale (tens of kilometres) hydro-mechanical (HM) model was assembled based primarily on site-specific litho-structural, hydrogeological and geomechanical data from the Whiteshell Research Area in the Canadian Shield, with simplification and generalization. Continental glaciological modelling of the Laurentide ice sheet through the last glacial cycle lasting approximately 100,000 years suggests that this site was glaciated at about 60 ka and between about 22.5 ka and 11 ka before present with maximum ice sheet thickness reaching 2,500 m and maximum basal water pressure head reaching 2000 m. The ice-sheet/drainage model was scaled down to generate spatially and temporally variable hydraulic and mechanical glaciated surface boundary conditions for site-scale subsurface HM modelling and permafrost modelling. Under extreme periglacial conditions permafrost was able to develop down to the assumed 500-m repository horizon. Two- and three-dimensional coupled HM finite-element simulations indicate: during ice-sheet advance there is rapid rise in hydraulic head, high transient hydraulic gradients and high groundwater velocities 2-3 orders of magnitude higher than under nonglacial conditions; surface water recharges deeper

  16. Paleoposition of the northern margin of Armorica in Late Devonian times: Paleomagnetic and rock magnetic results from the Frankenstein Intrusive Complex (Mid-German Crystalline Rise)

    Science.gov (United States)

    Zwing, Alexander; Bachtadse, Valerian

    2000-09-01

    A detailed rockmagnetic and paleomagnetic study of the Frankenstein Intrusive Complex (FIC, 363±7 Ma in age), southwestern Germany, has been carried out in order to test whether the paleomagnetic declinations within the internal parts of the European Variscides follow a common trend controlled by the structural grain of the orogen or whether the distribution of declinations follows a random pattern. In addition, new paleomagnetic data will contribute to further refine the drift history of the Armorican Terrane Assemblage during late Paleozoic times. The unmetamorphosed Frankenstein Igneous Complex forms part of the Mid-German Crystalline Rise within the Armorican Terrane Assemblage, amalgamated to Avalonia and Baltica during the Variscan orogeny, Stepwise thermal and alternating field (AF) demagnetization experiments identify four components (A, B, Cn, and Cr) of magnetization. Component A is a recent viscous overprint that parallels the present-day geomagnetic field. The high unblocking temperatures of A in some samples can be explained by the presence of multidomain magnetite. Component B is carried by hematite and is considered to be a late Carboniferous remagnetization. Components Cr and Cn, found in 110 samples from 20 sites, are antiparallel and pass a class C reversal test. Their primary origin is further supported by a contact test. Cr and Cn have maximum unblocking temperatures of up to 580°C and occasionally above over 600°C, indicating magnetite and hematite to carry the characteristic remanent magnetization. Ore microscopy revealed that primary hematite lamellae in ilmenite carry Cr and Cn and that a secondary generation of hematite is the carrier of B. The overall site mean direction of Cr and Cn (20 sites) based on endpoints and remagnetization circle analysis of 198°/40° (declination/inclination) with a 95% confidence limit (α95) of 4.9° and a precision parameter (k) of 45.0 defines a paleopole at 15°S, 9°W. When comparing to the apparent

  17. Characterisation and modelling of mixing processes in groundwaters of a potential geological repository for nuclear wastes in crystalline rocks of Sweden.

    Science.gov (United States)

    Gómez, Javier B; Gimeno, María J; Auqué, Luis F; Acero, Patricia

    2014-01-15

    This paper presents the mixing modelling results for the hydrogeochemical characterisation of groundwaters in the Laxemar area (Sweden). This area is one of the two sites that have been investigated, under the financial patronage of the Swedish Nuclear Waste and Management Co. (SKB), as possible candidates for hosting the proposed repository for the long-term storage of spent nuclear fuel. The classical geochemical modelling, interpreted in the light of the palaeohydrogeological history of the system, has shown that the driving process in the geochemical evolution of this groundwater system is the mixing between four end-member waters: a deep and old saline water, a glacial meltwater, an old marine water, and a meteoric water. In this paper we put the focus on mixing and its effects on the final chemical composition of the groundwaters using a comprehensive methodology that combines principal component analysis with mass balance calculations. This methodology allows us to test several combinations of end member waters and several combinations of compositional variables in order to find optimal solutions in terms of mixing proportions. We have applied this methodology to a dataset of 287 groundwater samples from the Laxemar area collected and analysed by SKB. The best model found uses four conservative elements (Cl, Br, oxygen-18 and deuterium), and computes mixing proportions with respect to three end member waters (saline, glacial and meteoric). Once the first order effect of mixing has been taken into account, water-rock interaction can be used to explain the remaining variability. In this way, the chemistry of each water sample can be obtained by using the mixing proportions for the conservative elements, only affected by mixing, or combining the mixing proportions and the chemical reactions for the non-conservative elements in the system, establishing the basis for predictive calculations.

  18. Reconstruction of in-situ porosity and porewater compositions of low-permeability crystalline rocks: Magnitude of artefacts induced by drilling and sample recovery.

    Science.gov (United States)

    Meier, D B; Waber, H N; Gimmi, T; Eichinger, F; Diamond, L W

    2015-12-01

    Geological site characterisation programmes typically rely on drill cores for direct information on subsurface rocks. However, porosity, transport properties and porewater composition measured on drill cores can deviate from in-situ values due to two main artefacts caused by drilling and sample recovery: (1) mechanical disruption that increases porosity and (2) contamination of the porewater by drilling fluid. We investigated the effect and magnitude of these perturbations on large drill core samples (12-20 cm long, 5 cm diameter) of high-grade, granitic gneisses obtained from 350 to 600 m depth in a borehole on Olkiluoto Island (SW Finland). The drilling fluid was traced with sodium-iodide. By combining out-diffusion experiments, gravimetry, UV-microscopy and iodide mass balance calculations, we successfully quantified the magnitudes of the artefacts: 2-6% increase in porosity relative to the bulk connected porosity and 0.9 to 8.9 vol.% contamination by drilling fluid. The spatial distribution of the drilling-induced perturbations was revealed by numerical simulations of 2D diffusion matched to the experimental data. This showed that the rims of the samples have a mechanically disrupted zone 0.04 to 0.22 cm wide, characterised by faster transport properties compared to the undisturbed centre (1.8 to 7.7 times higher pore diffusion coefficient). Chemical contamination was shown to affect an even wider zone in all samples, ranging from 0.15 to 0.60 cm, in which iodide enrichment was up to 180 mg/kg water, compared to 0.5 mg/kg water in the uncontaminated centre. For all samples in the present case study, it turned out that the magnitude of the artefacts caused by drilling and sample recovery is so small that no correction is required for their effects. Therefore, the standard laboratory measurements of porosity, transport properties and porewater composition can be taken as valid in-situ estimates. However, it is clear that the magnitudes strongly depend on site

  19. Reconstruction of in-situ porosity and porewater compositions of low-permeability crystalline rocks: Magnitude of artefacts induced by drilling and sample recovery.

    Science.gov (United States)

    Meier, D B; Waber, H N; Gimmi, T; Eichinger, F; Diamond, L W

    2015-12-01

    Geological site characterisation programmes typically rely on drill cores for direct information on subsurface rocks. However, porosity, transport properties and porewater composition measured on drill cores can deviate from in-situ values due to two main artefacts caused by drilling and sample recovery: (1) mechanical disruption that increases porosity and (2) contamination of the porewater by drilling fluid. We investigated the effect and magnitude of these perturbations on large drill core samples (12-20 cm long, 5 cm diameter) of high-grade, granitic gneisses obtained from 350 to 600 m depth in a borehole on Olkiluoto Island (SW Finland). The drilling fluid was traced with sodium-iodide. By combining out-diffusion experiments, gravimetry, UV-microscopy and iodide mass balance calculations, we successfully quantified the magnitudes of the artefacts: 2-6% increase in porosity relative to the bulk connected porosity and 0.9 to 8.9 vol.% contamination by drilling fluid. The spatial distribution of the drilling-induced perturbations was revealed by numerical simulations of 2D diffusion matched to the experimental data. This showed that the rims of the samples have a mechanically disrupted zone 0.04 to 0.22 cm wide, characterised by faster transport properties compared to the undisturbed centre (1.8 to 7.7 times higher pore diffusion coefficient). Chemical contamination was shown to affect an even wider zone in all samples, ranging from 0.15 to 0.60 cm, in which iodide enrichment was up to 180 mg/kg water, compared to 0.5 mg/kg water in the uncontaminated centre. For all samples in the present case study, it turned out that the magnitude of the artefacts caused by drilling and sample recovery is so small that no correction is required for their effects. Therefore, the standard laboratory measurements of porosity, transport properties and porewater composition can be taken as valid in-situ estimates. However, it is clear that the magnitudes strongly depend on site

  20. Reconstruction of in-situ porosity and porewater compositions of low-permeability crystalline rocks: Magnitude of artefacts induced by drilling and sample recovery

    Science.gov (United States)

    Meier, D. B.; Waber, H. N.; Gimmi, T.; Eichinger, F.; Diamond, L. W.

    2015-12-01

    Geological site characterisation programmes typically rely on drill cores for direct information on subsurface rocks. However, porosity, transport properties and porewater composition measured on drill cores can deviate from in-situ values due to two main artefacts caused by drilling and sample recovery: (1) mechanical disruption that increases porosity and (2) contamination of the porewater by drilling fluid. We investigated the effect and magnitude of these perturbations on large drill core samples (12-20 cm long, 5 cm diameter) of high-grade, granitic gneisses obtained from 350 to 600 m depth in a borehole on Olkiluoto Island (SW Finland). The drilling fluid was traced with sodium-iodide. By combining out-diffusion experiments, gravimetry, UV-microscopy and iodide mass balance calculations, we successfully quantified the magnitudes of the artefacts: 2-6% increase in porosity relative to the bulk connected porosity and 0.9 to 8.9 vol.% contamination by drilling fluid. The spatial distribution of the drilling-induced perturbations was revealed by numerical simulations of 2D diffusion matched to the experimental data. This showed that the rims of the samples have a mechanically disrupted zone 0.04 to 0.22 cm wide, characterised by faster transport properties compared to the undisturbed centre (1.8 to 7.7 times higher pore diffusion coefficient). Chemical contamination was shown to affect an even wider zone in all samples, ranging from 0.15 to 0.60 cm, in which iodide enrichment was up to 180 mg/kgwater, compared to 0.5 mg/kgwater in the uncontaminated centre. For all samples in the present case study, it turned out that the magnitude of the artefacts caused by drilling and sample recovery is so small that no correction is required for their effects. Therefore, the standard laboratory measurements of porosity, transport properties and porewater composition can be taken as valid in-situ estimates. However, it is clear that the magnitudes strongly depend on site- and

  1. Extremely enhanced photovoltaic properties of dye-sensitized solar cells by sintering mesoporous TiO2 photoanodes with crystalline titania chelated by acetic acid

    Science.gov (United States)

    Liu, Bo-Tau; Chou, Ya-Hui; Liu, Jin-Yan

    2016-04-01

    The study presents a significant improvement on the performance of dye-sensitized solar cells (DSSCs) through incorporating the crystalline titania chelated by acetic acid (TAc) into the mesoporous TiO2 photoanodes. The effects of TAc on the blocking layer, mesoporous TiO2 layer, and post-treatment have been investigated. The TAc blocking layer displays compact construction, revealing superior response time and resistance to suppress dark current compared to the blocking layer made from titanium(IV) isopropoxide (TTIP). The power conversion efficiency of DSSCs with the TAc treatment can reach as high as 10.49%, which is much higher than that of pristine DSSCs (5.67%) and that of DSSCs treated by TTIP (7.86%). We find that the TAc incorporation can lead to the decrease of charge transfer resistance and the increase of dye adsorption. The result may be attributed to the fact that the TAc possesses high crystallinity, exposed (101) planes, and acid groups chelated on surface, which are favorable for dye attachment and strong bonding at the FTO/TiO2 and the TiO2/TiO2 interfaces, These improvements result in the remarkable increase of photocurrent and thereby that of power conversion efficiency.

  2. Optimizing the crystallinity and acidity of H-SAPO-34 by fluoride for synthesizing Cu/SAPO-34 NH3-SCR catalyst.

    Science.gov (United States)

    Ma, Jing; Si, Zhichun; Wu, Xiaodong; Weng, Duan; Ma, Yue

    2016-03-01

    A series of H-SAPO-34 zeolites were synthesized by a hydrothermal method in fluoride media. The as-synthesized H-SAPO-34 zeolites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), N2 physisorption, temperature-programmed desorption of NH3 (NH3-TPD) and nuclear magnetic resonance (NMR) measurements. The results showed that a certain concentration of F(-) anions promoted the nucleation and crystallization of H-SAPO-34. The H-SAPO-34 synthesized in the fluoride media showed high crystallinity, uniform particle size distribution, large specific surface area and pore volume, and enhanced acidity. Therefore, Cu/SAPO-34 based on the fluoride-assisted zeolite showed a broadened temperature window for the selective catalytic reduction of NO by NH3 (NH3-SCR) reaction due to the enhanced acidity of the zeolite and the improved dispersion of copper species. PMID:26969071

  3. Optimizing the crystallinity and acidity of H-SAPO-34 by fluoride for synthesizing Cu/SAPO-34 NH3-SCR catalyst.

    Science.gov (United States)

    Ma, Jing; Si, Zhichun; Wu, Xiaodong; Weng, Duan; Ma, Yue

    2016-03-01

    A series of H-SAPO-34 zeolites were synthesized by a hydrothermal method in fluoride media. The as-synthesized H-SAPO-34 zeolites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), N2 physisorption, temperature-programmed desorption of NH3 (NH3-TPD) and nuclear magnetic resonance (NMR) measurements. The results showed that a certain concentration of F(-) anions promoted the nucleation and crystallization of H-SAPO-34. The H-SAPO-34 synthesized in the fluoride media showed high crystallinity, uniform particle size distribution, large specific surface area and pore volume, and enhanced acidity. Therefore, Cu/SAPO-34 based on the fluoride-assisted zeolite showed a broadened temperature window for the selective catalytic reduction of NO by NH3 (NH3-SCR) reaction due to the enhanced acidity of the zeolite and the improved dispersion of copper species.

  4. Solution of rocks and refractory minerals by acids at high temperatures and pressures. Determination of silica after decomposition with hydrofluoric acid

    Science.gov (United States)

    May, I.; Rowe, J.J.

    1965-01-01

    A modified Morey bomb was designed which contains a removable nichromecased 3.5-ml platinium crucible. This bomb is particularly useful for decompositions of refractory samples for micro- and semimicro-analysis. Temperatures of 400-450?? and pressures estimated as great as 6000 p.s.i. were maintained in the bomb for periods as long as 24 h. Complete decompositions of rocks, garnet, beryl, chrysoberyl, phenacite, sapphirine, and kyanite were obtained with hydrofluoric acid or a mixture of hydrofluoric and sulfuric acids; the decomposition of chrome refractory was made with hydrochloric acid. Aluminum-rich samples formed difficultly soluble aluminum fluoride precipitates. Because no volatilization losses occur, silica can be determined on sample solutions by a molybdenum-blue procedure using aluminum(III) to complex interfering fluoride. ?? 1965.

  5. Volcanic stratigraphy of intermediate to acidic rocks in southern Paraná Magmatic Province, Brazil

    Directory of Open Access Journals (Sweden)

    Liza Angélica Polo

    2014-06-01

    Full Text Available This article presents the first map in detail scale for an area covered by Palmas type volcanic rocks in the south border of the eocretaceous Paraná Magmatic Province, south Brazil. The study of the structural features coupled with petrography and geochemistry made it possible to separate these rocks into three main volcanic sequences and recognize their stratigraphy. The older Caxias do Sul sequence rests directly over the first low-Ti basalt flows (Gramado type, and corresponds to the stacking of lobated lava flows, laminar flows and lava domes, mostly emitted as continuous eruptions; only the latest eruptions are intercalated with thin sandstone deposits. These rocks have dacitic composition (~ 68 wt% SiO2 with microphenocrysts of plagioclase and subordinate pyroxenes and Ti-magnetite immersed in glassy or devitrified matrix. A second volcanic sequence, named Barros Cassal, is composed of several lava flows of basaltic andesite, andesitic and dacitic composition (~ 54; ~ 57 and ~ 63 wt% SiO2 , respectively, with microphenocrysts of plagioclase, pyroxenes and Ti-magnetite. The frequent intercalation of sandstone between the flows attests to the intermittent behaviour of this event. The upper sequence, Santa Maria, is made up of more silica-rich (~ 70 wt% SiO2 rocks occurring as laminar flows, lobated flows and lava-domes. These rocks have rhyolitic composition with microphenocrysts of plagioclase and Ti-magnetite set in a glassy or devitrified matrix with microlites. The structures and textures of all three silicic sequences favor the interpretation that they had a predominantly effusive character, which is thought to be a reflection of the remarkably high temperatures of the lavas (~ 1,000 ºC.

  6. Generic Crystalline Disposal Reference Case

    Energy Technology Data Exchange (ETDEWEB)

    Painter, Scott Leroy [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Chu, Shaoping [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Harp, Dylan Robert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Perry, Frank Vinton [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wang, Yifeng [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-02-20

    A generic reference case for disposal of spent nuclear fuel and high-level radioactive waste in crystalline rock is outlined. The generic cases are intended to support development of disposal system modeling capability by establishing relevant baseline conditions and parameters. Establishment of a generic reference case requires that the emplacement concept, waste inventory, waste form, waste package, backfill/buffer properties, EBS failure scenarios, host rock properties, and biosphere be specified. The focus in this report is on those elements that are unique to crystalline disposal, especially the geosphere representation. Three emplacement concepts are suggested for further analyses: a waste packages containing 4 PWR assemblies emplaced in boreholes in the floors of tunnels (KBS-3 concept), a 12-assembly waste package emplaced in tunnels, and a 32-assembly dual purpose canister emplaced in tunnels. In addition, three failure scenarios were suggested for future use: a nominal scenario involving corrosion of the waste package in the tunnel emplacement concepts, a manufacturing defect scenario applicable to the KBS-3 concept, and a disruptive glaciation scenario applicable to both emplacement concepts. The computational approaches required to analyze EBS failure and transport processes in a crystalline rock repository are similar to those of argillite/shale, with the most significant difference being that the EBS in a crystalline rock repository will likely experience highly heterogeneous flow rates, which should be represented in the model. The computational approaches required to analyze radionuclide transport in the natural system are very different because of the highly channelized nature of fracture flow. Computational workflows tailored to crystalline rock based on discrete transport pathways extracted from discrete fracture network models are recommended.

  7. 热-水-力耦合作用下结晶岩渗透特性演化模型%A PERMEABILITY EVOLUTION MODEL FOR CRYSTALLINE ROCKS SUBJECTED TO COUPLED THERMO-HYDRO-MECHANICAL LOADING

    Institute of Scientific and Technical Information of China (English)

    陈益峰; 胡冉; 周创兵; 井兰如

    2013-01-01

    An anisotropic damage model was established for fluid-saturated crystalline rocks of low permeability in coupled thermo-hydro-mechanical(THM) loading conditions by using the micromechanical approach in the framework of thermodynamics. The proposed damage model accounts for the impacts of some important micromechanisms,such as the interstitial water pressure,normal stiffness recovery induced by compressed microcracks and sliding and shear dilatancy of closed microcracks,on the macromechanical properties of rocks under non-isothermal condition. On this basis,using various homogenization approaches,estimates were presented for the variations in effective permeability of cracked rocks induced by anisotropic damage propagation. The predictive limitations associated with the lower bound estimates for the effective permeability of damaged rocks were discussed;and a rigorous upper bound estimate was then presented to account for the influence of some important microstructural features,such as the connectivity and persistence of microcrack system,on the permeability variation. Existing laboratory tests on granite samples for damage-induced variation in permeability in triaxial condition and for uniaxial mechanical response after high-temperature thermal treatment,together with the in-situ measurements of excavation-induced damage zone and permeability variation in the surrounding rock of the TSX tunnel,were used to validate the proposed models.%在热力学框架下,采用细观力学方法,建立热-水-力(THM)耦合条件下低渗饱水结晶岩的各向异性损伤模型,考虑非等温条件下微裂纹水压力作用、法向刚度恢复以及滑动剪胀等细观力学机制对岩石宏观力学性能的影响。在此基础上,采用均匀化方法,建立各向异性损伤诱发的岩石有效渗透特性演化模型,指出损伤岩石有效渗透特性下限估计模型的局限性,进而给出可反映损伤演化过程中微裂纹连通性等细

  8. Hydrothermal synthesis of highly crystalline RuS{sub 2} nanoparticles as cathodic catalysts in the methanol fuel cell and hydrochloric acid electrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yanjuan [Key Laboratory of Marine Chemistry Theory and Technology, Minisry of Education Ocean University of China, Qingdao, 266100 (China); College of Material Science and Engineering, Key Laboratory of Automobile Materials of Ministry of Education, Jilin University, 2699 Qianjin Street, Changchun 130012 (China); Li, Nan, E-mail: lin@jlu.edu.cn [College of Material Science and Engineering, Key Laboratory of Automobile Materials of Ministry of Education, Jilin University, 2699 Qianjin Street, Changchun 130012 (China); Yanagisawa, Kazumichi [Research Laboratory of Hydrothermal Chemistry, Kochi University, Kochi 780-8520 (Japan); Li, Xiaotian [College of Material Science and Engineering, Key Laboratory of Automobile Materials of Ministry of Education, Jilin University, 2699 Qianjin Street, Changchun 130012 (China); Yan, Xiao [Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012 (China)

    2015-05-15

    Highlights: • Highly crystalline RuS{sub 2} nanoparticles have been first synthesized by a “one-step” hydrothermal method. • The product presents a pure cubic phase of stoichiometric ratio RuS{sub 2} with average particle size of 14.8 nm. • RuS{sub 2} nanoparticles were used as cathodic catalysts in methanol fuel cell and hydrochloric acid electrolysis. • The catalyst outperforms commercial Pt/C in methanol tolerance and stability towards Cl{sup −}. - Abstract: Highly crystalline ruthenium sulfide (RuS{sub 2}) nanoparticles have been first synthesized by a “one-step” hydrothermal method at 400 °C, using ruthenium chloride and thiourea as reactants. The products were characterized by powder X-ray diffraction (XRD), scanning electron microscopy/energy disperse spectroscopy (SEM/EDS), thermo gravimetric-differential thermal analyze (TG-DTA), transmission electron microscopy equipped with selected area electron diffraction (TEM/SAED). Fourier transform infrared spectra (IR), and X-ray photoelectron spectroscopy (XPS). XRD result illustrates that the highly crystalline product presents a pure cubic phase of stoichiometric ratio RuS{sub 2} and the average particle size is 14.8 nm. SEM and TEM images display the products have irregular shape of 6–25 nm. XPS analyst indicates that the sulfur exists in the form of S{sub 2}{sup 2−}. Cyclic voltammetry (CV), rotating disk electrode (RDE), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS) measurements are conducted to evaluate the electrocatalytic activity and stability of the highly crystalline RuS{sub 2} nanoparticles in oxygen reduction reaction (ORR) for methanol fuel cell and hydrochloric acid electrolysis. The results illustrate that RuS{sub 2} is active towards oxygen reduction reaction. Although the activity of RuS{sub 2} is lower than that of Pt/C, the RuS{sub 2} catalyst outperforms commercial Pt/C in methanol tolerance and stability towards Cl{sup −}.

  9. Diavik Waste Rock Project: Evolution of Mineral Weathering, Element Release, and Acid Generation and Neutralization during a Five-Year Humidity Cell Experiment

    OpenAIRE

    Jeff B. Langman; Mandy L. Moore; Carol J. Ptacek; Leslie Smith; David Sego; David W. Blowes

    2014-01-01

    A five-year, humidity-cell experiment was used to study the weathering evolution of a low-sulfide, granitic waste rock at 5 and 22 °C. Only the rock with the highest sulfide content (0.16 wt %) released sufficient acid to overcome a limited carbonate acid-neutralization capacity and produce a substantial decline in pH. Leached SO4 and Ca quickly increased then decreased during the first two years of weathering. Sulfide oxidation continued to release acid and SO4 after carbonate depletion, res...

  10. Stabile Chlorine Isotope Study of Martian Shergottites and Nakhlites; Whole Rock and Acid Leachates and Residues

    Science.gov (United States)

    Nakamura, N.; Nyquist, L. E.; Reese, Y.; Shih, C-Y; Fujitani, T.; Okano, O.

    2011-01-01

    We have established a precise analytical technique for stable chlorine isotope measurements of tiny planetary materials by TIMS (Thermal Ionization Mass Spectrometry) [1], for which the results are basically consistent with the IRMS tech-nique (gas source mass spectrometry) [2,3,4]. We present here results for Martian shergottites and nakhlites; whole rocks, HNO3-leachates and residues, and discuss the chlorine isotope evolution of planetary Mars.

  11. Effects of crystalline menthol on blood metabolites in Holstein steers and in vitro volatile fatty acid and gas production.

    Science.gov (United States)

    Van Bibber-Krueger, C L; Miller, K A; Aperce, C C; Alvarado-Gilis, C A; Higgins, J J; Drouillard, J S

    2016-03-01

    Fifty-two Holstein steers (573 ± 9.92 kg BW) were used to determine if oral administration of crystalline menthol would induce changes in endogenous secretions of IGF-1 and circulating concentrations of glucose, lactate, and plasma urea nitrogen (PUN). Steers were blocked by BW and assigned within block to treatment. Treatments consisted of 0, 0.003, 0.03, or 0.3% crystalline menthol (DM basis) added to the diet. Animals were housed in individual, partially covered pens equipped with feed bunks and automatic water fountains. On d 1 of the experiment, blood samples were obtained via jugular venipuncture at 0, 6, 12, 18, and 24 h after feeding. Treatment administration commenced on d 2, and blood samples were again drawn at 0, 6, 12, 18, and 24 h after feeding. This blood-sampling schedule was repeated on d 9, 16, 23, and 30. Plasma was analyzed for PUN, glucose, and lactate concentrations. Serum was used to analyze IGF-1 concentration. Body weights were measured on d 1, 9, 16, 23, and 30. To accompany the live animal phase, in vitro fermentations were performed using ruminal fluid cultures. Measurements included VFA concentrations and fermentative gas production for cultures containing crystalline menthol at 0, 0.003, 0.03, or 0.3% of substrate DM. Addition of menthol to the diet of steers resulted in a treatment × day interaction ( plasma glucose. Cattle fed 0 and 0.003% menthol had greater serum IGF-1 concentrations on d 2 compared with steers fed 0.03% menthol. Steers fed 0% menthol had greater serum IGF-1 concentrations on d 9 compared with steers fed 0.03 and 0.3% menthol, whereas no differences were observed on d 23 or 30. Plasma glucose was similar among treatments until d 23, when steers supplemented with 0.03% menthol had lower glucose concentrations. Plasma urea nitrogen concentrations were not different among treatments; however, PUN concentrations varied by day. A linear response was detected for BW ( = 0.03), with steers consuming 0% menthol having

  12. Etching of Crystalline ZnO Surfaces upon Phosphonic Acid Adsorption: Guidelines for the Realization of Well-Engineered Functional Self-Assembled Monolayers.

    Science.gov (United States)

    Ostapenko, Alexandra; Klöffel, Tobias; Eußner, Jens; Harms, Klaus; Dehnen, Stefanie; Meyer, Bernd; Witte, Gregor

    2016-06-01

    Functionalization of metal oxides by means of covalently bound self-assembled monolayers (SAMs) offers a tailoring of surface electronic properties such as their work function and, in combination with its large charge carrier mobility, renders ZnO a promising conductive oxide for use as transparent electrode material in optoelectronic devices. In this study, we show that the formation of phosphonic acid-anchored SAMs on ZnO competes with an unwanted chemical side reaction, leading to the formation of surface precipitates and severe surface damage at prolonged immersion times of several days. Combining atomic force microscopy (AFM), X-ray diffraction (XRD), and thermal desorption spectroscopy (TDS), the stability and structure of the aggregates formed upon immersion of ZnO single crystal surfaces of different orientations [(0001̅), (0001), and (101̅0)] in phenylphosphonic acid (PPA) solution were studied. By intentionally increasing the immersion time to more than 1 week, large crystalline precipitates are formed, which are identified as zinc phosphonate. Moreover, the energetics and the reaction pathway of this transformation have been evaluated using density functional theory (DFT), showing that zinc phosphonate is thermodynamically more favorable than phosphonic acid SAMs on ZnO. Precipitation is also found for phosphonic acids with fluorinated aromatic backbones, while less precipitation occurs upon formation of SAMs with phenylphosphinic anchoring units. By contrast, no precipitates are formed when PPA monolayer films are prepared by sublimation under vacuum conditions, yielding smooth surfaces without noticeable etching. PMID:27159837

  13. Effect of cobalt and DL-malic acid on the growth rate, crystalline perfection, optical, mechanical, dielectric, piezoelectric properties and SHG efficiency of ADP single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Rajesh, P. [Centre for Crystal Growth, SSN College of Engineering, Kalavakkam 603110, Chennai, Tamilnadu 603110 (India); Ramasamy, P., E-mail: ramasamyp@ssn.edu.i [Centre for Crystal Growth, SSN College of Engineering, Kalavakkam 603110, Chennai, Tamilnadu 603110 (India); Kumar, Binay [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India); Bhagavannarayana, G. [Materials characterization Division, National Physical Laboratory, New Delhi 110 012 (India)

    2010-05-15

    Effects of the additions of cobalt (II) acetate hexahydrate and DL-malic acid on the growth and various properties of ammonium dihydrogen orthophosphate single crystals grown by slow evaporation method have been studied. The grown crystals were subjected to UV-vis, microhardness, dielectric, piezoelectric, high resolution X-ray diffraction and SHG studies. UV spectra show good transparency in the entire visible region which is an essential requirement for a nonlinear optical crystal. Vickers hardness study carried out on (1 0 0) face at room temperature shows increased hardness of the crystals added with DL-malic acid compared to the pure and cobalt (II) acetate hexahydrate added crystals. Dielectric constant and dielectric loss were measured for the grown crystals for different frequencies and temperatures. It reveals that the DL-malic acid added ADP crystals have low dielectric loss. Crystalline perfection of the grown crystals was analyzed using HRXRD. Good piezoelectric behaviour was observed for all the crystals. Preliminary measurements indicate that the second harmonic generation efficiency of the DL-malic acid doped crystals is greater than pure and cobalt (II) acetate hexahydrate added ADP.

  14. Nuclear magnetic resonance studies of amino acids and proteins. Side-chain mobility of methionine in the crystalline amonio acid and in crystallne sperm whale (Physeter catodon) myoglobin

    International Nuclear Information System (INIS)

    Deuterium (2H) nuclear magnetic resonance (NMR) spectra and spin-lattice relaxation times (T1) were obtained of L-[epsilon-2H3]methionine, L-[epsilon-2H3]methionine in a D,L lattice, and [S-methyl-2H3]methionine in the crystalline solid state, as a function of temperature, in addition to obtaining 2H T1 and line-width results as a function of temperature on [epsilon-2H3]methionine-labeled sperm whale (Physeter catodon) myoglobins by using the method of magnetic ordering. Also recorded were 13C cross-polarization ''magic-angle'' sample-spinning NMR spectra of [epsilon-13C]methionine-labeled crystalline cyanoferrimyoglobin (at 37.7 MHz, corresponding to a magnetic field strength of 3.52 T) and of the same protein in aqueous solution

  15. Crystal structures and hydrogen bonding in the co-crystalline adducts of 3,5-dinitrobenzoic acid with 4-aminosalicylic acid and 2-hydroxy-3-(1H-indol-3-ylpropenoic acid

    Directory of Open Access Journals (Sweden)

    Graham Smith

    2014-10-01

    Full Text Available The structures of the co-crystalline adducts of 3,5-dinitrobenzoic acid (3,5-DNBA with 4-aminosalicylic acid (PASA, the 1:1 partial hydrate, C7H4N2O6·C7H7NO3·0.2H2O, (I, and with 2-hydroxy-3-(1H-indol-3-ylpropenoic acid (HIPA, the 1:1:1 d6-dimethyl sulfoxide solvate, C7H4N2O6·C11H9NO3·C2D6OS, (II, are reported. The crystal substructure of (I comprises two centrosymmetric hydrogen-bonded R22(8 homodimers, one with 3,5-DNBA, the other with PASA, and an R22(8 3,5-DNBA–PASA heterodimer. In the crystal, inter-unit amine N—H...O and water O—H...O hydrogen bonds generate a three-dimensional supramolecular structure. In (II, the asymmetric unit consists of the three constituent molecules, which form an essentially planar cyclic hydrogen-bonded heterotrimer unit [graph set R32(17] through carboxyl, hydroxy and amino groups. These units associate across a crystallographic inversion centre through the HIPA carboxylic acid group in an R22(8 hydrogen-bonding association, giving a zero-dimensional structure lying parallel to (100. In both structures, π–π interactions are present [minimum ring-centroid separations = 3.6471 (18 Å in (I and 3.5819 (10 Å in (II].

  16. Experimental Acid Weathering of Fe-Bearing Mars Analog Minerals and Rocks: Implications for Aqueous Origin of Hematite-Bearing Sediments in Meridiani Planum, Mars

    Science.gov (United States)

    Golden, D. C.; Koster, A. M.; Ming, D. W.; Morris, R. V.; Mertzman, S. A.

    2011-01-01

    A working hypothesis for Meridiani evaporite formation involves the evaporation of fluids derived from acid weathering of Martian basalts and subsequent diagenesis [1, 2]. However, there are no reported experimental studies for the formation of jarosite and gray hematite (spherules), which are characteristic of Meridiani rocks from Mars analog precursor minerals. A terrestrial analog for hematite spherule formation from basaltic rocks under acidic hydrothermal conditions has been reported [3], and we have previously shown that the hematite spherules and jarosite can be synthetically produced in the laboratory using Fe3+ -bearing sulfate brines under hydrothermal conditions [4]. Here we expand and extend these studies by reacting Mars analog minerals with sulfuric acid to form Meridiani-like rock-mineral compositions. The objective of this study is to provide environmental constraints on past aqueous weathering of basaltic materials on Mars.

  17. Site characterization in fractured crystalline rock

    International Nuclear Information System (INIS)

    This report concerns a study which is part of the SKI performance assessment project SITE-94. SITE-94 is a performance assessment of a hypothetical repository at a real site. The main objective of the project is to determine how site specific data should be assimilated into the performance assessment process and to evaluate how uncertainties inherent in site characterization will influence performance assessment results. Other important elements of SITE-94 are the development of a practical and defensible methodology for defining, constructing and analyzing scenarios, the development of approaches for treatment of uncertainties, evaluation of canister integrity, and the development and application of an appropriate Quality Assurance plan for Performance Assessments. (111 refs.)

  18. Comparison of hot hydroxylamine hydrochloride and oxalic acid leaching of stream sediment and coated rock samples as anomaly enhancement techniques

    Science.gov (United States)

    Filipek, L.H.; Chao, T.T.; Theobald, P.K.

    1982-01-01

    A hot hydroxylamine hydrochloride (H-Hxl) extraction in 25% acetic acid is compared with the commonly used oxalic acid extraction as a method of anomaly enhancement for Cu and Zn in samples from two very different metal deposits and climatic environments. Results obtained on minus-80-mesh stream sediments from an area near the Magruder massive sulfide deposit in Lincoln County, Georgia, where the climate is humid subtropical, indicate that H-Hxl enhances the anomaly for Cu by a factor of 2 and for Zn by a factor of 1.5, compared to the oxalic method. Analyses of Fe oxide-coated rock samples from outcrops overlying the North Silver Bell porphyry copper deposit near Tucson, Arizona, where the climate is semi-arid to arid, indicate that both techniques effectively outline the zones of hydrothermal alteration. The H-Hxl extraction can also perform well in high-carbonate or high-clay environments, where other workers have suggested that oxalic acid is not very effective. Therefore, the H-Hxl method is recommended for general exploration use. ?? 1982.

  19. Oxalic-acid leaching of rock, soil, and stream-sediment samples as an anomaly-accentuated technique

    Science.gov (United States)

    Alminas, Henry V.; Mosier, Elwin L.

    1976-01-01

    In many instances total-rock and sieved-soil and stream-sediment samples lack the sensitivity and contrast required for reconnaissance exploration and necessary in the search for blind ore deposits. Heavy-mineral concentrates incorporate the required sensitivity and contrast but are overly expensive for two reasons: time-consuming sample preparation is required to obtain them, and they cannot be easily derived from all bulk-sample types. Trace-metal-content comparisons of the oxalic-acid-leachable portions with heavy-mineral concentrates show that the leachates are equal to the heavy-mineral concentrates in sensitivity and contrast. Simplicity of preparation and the resultant cost savings are additional advantages of this proposed method.

  20. ACCESSIBILITY AND CRYSTALLINITY OF CELLULOSE

    Directory of Open Access Journals (Sweden)

    Michael Ioelovich

    2009-08-01

    Full Text Available The accessibility of cellulose samples having various degrees of crystallinity was studied with respect to molecules of water, lower primary alcohols, and lower organic acids. It was found that small water molecules have full access to non-crystalline domains of cellulose (accessibility coefficient α = 1. Molecules of the lowest polar organic liquids (methanol, ethanol, and formic acid have partial access into the non-crystalline domains (α<1, and with increasing diameter of the organic molecules their accessibility to cellulose structure decreases. Accessibility of cellulose samples to molecules of various substances is a linear function of the coefficient α and the content of non-crystalline domains. The relationship between crystallinity (X and accessibility (A of cellulose to molecules of some liquids has been established as A = α (1-X. The water molecules were found to have greater access to cellulose samples than the molecules of the investigated organic liquids. The obtained results permit use of accessibility data to estimate the crystallinity of cellulose, to examine the structural state of non-crystalline domains, and to predict the reactivity of cellulose samples toward some reagents.

  1. Phosphorus leaching in an acid tropical soil "recapitalized" with phosphate rock and triple superphosphate.

    Science.gov (United States)

    Gikonyo, Esther W; Zaharah, Abdul R; Hanafi, Mohamed M; Anuar, Rahim A

    2010-01-01

    With high rates of phosphorus applied to increase "capital P" as a stock for plant uptake over several years, the question of P leaching is inevitable. We conducted an intact soil column experiment in the field to evaluate P leached from soils treated with triple superphosphate (TSP) and Gafsa phosphate rock (GPR) at 300, 600, and 900 kg P ha-1 with and without integration of cattle manure. The lysimeters, made from PVC tubes of 30-cm length, were inserted into the soil up to the 25-cm depth. The tubes were fitted with a resin bag containing a mixture of cation and anion exchange resin (50:50) at the lower end of the tube inserted into the soil. The tubes, arranged in a completely randomized design, were sampled randomly at 10-week intervals for 12 months. Phosphorus extractable from the top- and subsoil at the end of experiment and leached P were determined. More P was leached out from TSP (threefold) compared to GPR, and the amount of P leached increased with increasing rates of P fertilizer applied. Application of manure intensified the amounts of P leached from TSP, particularly at the 6-month sampling time. There was hardly any substantial P leached from the soil treated with GPR. Thus, for effective and efficient long-term P fertilizer management strategies, choosing the right P fertilizer source and monitoring P losses through leaching has to be done for enhanced fertilizer use efficiency and thus reducing P pollution of ground waters. PMID:20694445

  2. Phosphorus Leaching in an Acid Tropical Soil “Recapitalized” with Phosphate Rock and Triple Superphosphate

    Directory of Open Access Journals (Sweden)

    E. Gikonyo

    2010-01-01

    Full Text Available With high rates of phosphorus applied to increase “capital P” as a stock for plant uptake over several years, the question of P leaching is inevitable. We conducted an intact soil column experiment in the field to evaluate P leached from soils treated with triple superphosphate (TSP and Gafsa phosphate rock (GPR at 300, 600, and 900 kg P ha-1 with and without integration of cattle manure. The lysimeters, made from PVC tubes of 30-cm length, were inserted into the soil up to the 25-cm depth. The tubes were fitted with a resin bag containing a mixture of cation and anion exchange resin (50:50 at the lower end of the tube inserted into the soil. The tubes, arranged in a completely randomized design, were sampled randomly at 10-week intervals for 12 months. Phosphorus extractable from the top- and subsoil at the end of experiment and leached P were determined. More P was leached out from TSP (threefold compared to GPR, and the amount of P leached increased with increasing rates of P fertilizer applied. Application of manure intensified the amounts of P leached from TSP, particularly at the 6-month sampling time. There was hardly any substantial P leached from the soil treated with GPR. Thus, for effective and efficient long-term P fertilizer management strategies, choosing the right P fertilizer source and monitoring P losses through leaching has to be done for enhanced fertilizer use efficiency and thus reducing P pollution of ground waters.

  3. Acid neutralizing capacity and leachate results for igneous rocks, with associated carbon contents of derived soils, Animas River AML site, Silverton, Colorado

    Science.gov (United States)

    Yager, Douglas B.; Stanton, Mark R.; Choate, LaDonna M.; Burchell,

    2009-01-01

    Mine planning efforts have historically overlooked the possible acid neutralizing capacity (ANC) that local igneous rocks can provide to help neutralize acidmine drainage. As a result, limestone has been traditionally hauled to mine sites for use in neutralizing acid drainage. Local igneous rocks, when used as part of mine life-cycle planning and acid mitigation strategy, may reduce the need to transport limestone to mine sites because these rocks can contain acid neutralizing minerals. Igneous hydrothermal events often introduce moderately altered mineral assemblages peripheral to more intensely altered rocks that host metal-bearing veins and ore bodies. These less altered rocks can contain ANC minerals (calcite-chlorite-epidote) and are referred to as a propylitic assemblage. In addition, the carbon contents of soils in areas of new mining or those areas undergoing restoration have been historically unknown. Soil organic carbon is an important constituent to characterize as a soil recovery benchmark that can be referred to during mine cycle planning and restoration. This study addresses the mineralogy, ANC, and leachate chemistry of propylitic volcanic rocks that host polymetallic mineralization in the Animas River watershed near the historical Silverton, Colorado, mining area. Acid titration tests on volcanic rocks containing calcite (2 – 20 wt %) and chlorite (6 – 25 wt %), have ANC ranging from 4 – 146 kg/ton CaCO3 equivalence. Results from a 6-month duration, kinetic reaction vessel test containing layered pyritic mine waste and underlying ANC volcanic rock (saturated with deionized water) indicate that acid generating mine waste (pH 2.4) has not overwhelmed the ANC of propylitic volcanic rocks (pH 5.8). Sequential leachate laboratory experiments evaluated the concentration of metals liberated during leaching. Leachate concentrations of Cu-Zn-As-Pb for ANC volcanic rock are one-to-three orders of magnitude lower when compared to leached solution from

  4. Stabilisation of acid generating waste rock with fly ash : immobilization of arsenic under alkaline conditions

    Energy Technology Data Exchange (ETDEWEB)

    Backstrom, M. [Orebro Univ. (Sweden). Man-Technology Environment Research Centre; Sartz, L. [Bergslagen, Kopparberg (Sweden)

    2010-07-01

    This study evaluated the potential for using fly ash as an alkaline material for increasing the pH and decreasing arsenic leaching from highly acidic mine waste. A wood ash sample known to contain high concentrations of both calcium and barium was tested with highly acidic mine waste samples that leached approximately 200 mg/L of arsenic at a liquid/solid ratio of 2. Samples were mixed with the fly ash. Control samples consisted of only mine waste, while the amended samples contained 10 g of mine waste and 10 g of wood ash. Ultra pure water was used as a leachant for both systems until the liquid-solid ratio that corresponded to 900 years of drainage for a waste pile that was 3 m high with an annual run-off of 300 mm. Results of the experimental study showed that the pH in the control increased from 1.7 to 2.7, while the pH in the amended system decreased from 12.6 to 11.5. Initial concentrations of arsenic decreased by almost 3 orders of magnitude in the amended systems. Co-precipitation with the iron, and the calcium arsenate precipitation process were identified as the principal arsenic immobilization mechanisms. The study demonstrated that under the right chemical conditions, alkaline amendments can be used to reduce arsenic leaching from mine wastes. 5 refs., 2 tabs., 1 fig.

  5. Crystalline Confinement

    CERN Document Server

    Banerjee, D; Jiang, F -J; Wiese, U -J

    2013-01-01

    We show that exotic phases arise in generalized lattice gauge theories known as quantum link models in which classical gauge fields are replaced by quantum operators. While these quantum models with discrete variables have a finite-dimensional Hilbert space per link, the continuous gauge symmetry is still exact. An efficient cluster algorithm is used to study these exotic phases. The $(2+1)$-d system is confining at zero temperature with a spontaneously broken translation symmetry. A crystalline phase exhibits confinement via multi-stranded strings between charge-anti-charge pairs. A phase transition between two distinct confined phases is weakly first order and has an emergent spontaneously broken approximate $SO(2)$ global symmetry. The low-energy physics is described by a $(2+1)$-d $\\mathbb{R}P(1)$ effective field theory, perturbed by a dangerously irrelevant $SO(2)$ breaking operator, which prevents the interpretation of the emergent pseudo-Goldstone boson as a dual photon. This model is an ideal candidat...

  6. Isolation and characterization of ancient hydrocarbon biomarkers from crystalline minerals

    Science.gov (United States)

    Summons, R. E.; Carrasquillo, A.; Hallmann, C.; Sherman, L. S.; Waldbauer, J. R.

    2008-12-01

    Hydrocarbon biomarker analysis is conventionally conducted on bitumen (soluble fossilized organic matter) extracted from sedimentary rocks using organic solvents. Biomarkers can also be generated by pyrolysis of kerogen (insoluble organic matter) in the same rocks. These approaches have met with much success where the organic matter has not seen significant levels of thermal metamorphism but more limited success when applied to thermally mature Archean rocks. Biomarkers have also been isolated from fluid inclusions of crystalline minerals and this approach has found wide application in petroleum exploration because of the capability of minerals that form crystals in reservoir rocks to trap organics from different episodes of fluid migration. Lastly, biogenic crystalline minerals are well known to trap organics including amino acids, fatty acids or hydrocarbons from those organisms that laid down the minerals. In fact, recent observations suggest that hydrocarbon biomarkers can be abundantly preserved in crystalline minerals where they may be protected over long periods of time and also distinguished from more recent generations of organics from endolithic organisms (modern) or anthropogenic (fossil hydrocarbon) contaminants. Here we report analyses of biomarker lipids trapped in fluid inclusions or otherwise having a "tight association" with the minerals in sedimentary rocks from Neoarchean and Paleoproterozoic successions in Australia and Southern Africa. In particular, cores recovered from the Agouron Griqualand Drilling Project contain over 2500m of well-preserved late Archean Transvaal Supergroup sediments, dating from ca. 2.67 to 2.46Ga. Bitumen extracts of samples from these strata were obtained using clean drilling, sampling and handling protocols and without overprinting with contaminant hydrocarbons. Dissolution of the mineral matrix of extracted sediments, followed by another solvent extraction, yielded a second bitumen that comprised hydrocarbons that

  7. Comparative study on precipitation methods of yellow-cake from acid leachate of rock phosphate and Its purification

    International Nuclear Information System (INIS)

    This study was carried-out to leach uranium from rock phosphate using sulphuric acid in presences of potassium chlorate as an oxidant and to investigate the relative purity of different forms of yellow cakes produced with ammonia ((NH4)2 U2 O7), magnesia (UO3.xH2O) and sodium hydroxide (Na2U2O7) as precipitants, as well as purification of the products with TBP extraction and matching its impurity levels with specification of the commercial products. Alpha-particle spectrometry was for used for determination of activity concentration of uranium isotopes (''2''3''4U and ''2''3''8U) in rock phosphate, resulting green phosphoric acid solution, and in different forms of the yellow cake from which the equivalent mass concentration of uranium was deduced. Likewise, AAS was used for determination of impurities (Pb, Ni, Cd, Fe, Zn, Mn, and Cu). On the average, the activity concentration of uranium in the rock phosphate was 1468±979 Bq/Kg (119.38±79.66 ppm), and 711±252 Bq/L (57.85±20.46 ppm) in the resulting green solution with corresponding percent of dissolution amounting to 48% which is considered low indicating that the experimental conditions (i.e. dissolution container, temperature, PH, retention time) were not optimal. However, the isotopic ratio (''2''3''4U, ''2''3''8U) in all stages of hydrometallurgical process was not much different from unity indicating lack of fractionation. Crude yellow cakes (hydrate uranium trioxide, ammonium diuranate and sodium diuranate) were precipitated from the green solutions prior to separation of iron and once after iron separation. Although, iron was tested using bipyridine and SCN, it was found in all types of crude samples analyzed this might be attributed to either the quality of the reagent used or inhibition of Fe present in the solution by stronger complexing agent. Uranium mass concentration in crude yellow cakes precipitated before iron separation was found following the order: UO3.xH2O>ammonium diuranate

  8. Programme of research into the disposal of radioactive waste into geological formations. Studies on crystalline rock. Contract 059-78-1 WASUK. Final report: General studies of physical properties

    International Nuclear Information System (INIS)

    This report covers the following topics: groundwater dating; heat transfer and associated thermal studies (in-situ heat transfer experiment; thermal rock and fluid mechanics studies; thermal convection; hydraulic permeability experiments; laboratory studies); corrosion and chemical compatibility studies (field and laboratory corrosion studies; waste - rock interactions). (U.K.)

  9. Diavik Waste Rock Project: Evolution of Mineral Weathering, Element Release, and Acid Generation and Neutralization during a Five-Year Humidity Cell Experiment

    Directory of Open Access Journals (Sweden)

    Jeff B. Langman

    2014-04-01

    Full Text Available A five-year, humidity-cell experiment was used to study the weathering evolution of a low-sulfide, granitic waste rock at 5 and 22 °C. Only the rock with the highest sulfide content (0.16 wt % released sufficient acid to overcome a limited carbonate acid-neutralization capacity and produce a substantial decline in pH. Leached SO4 and Ca quickly increased then decreased during the first two years of weathering. Sulfide oxidation continued to release acid and SO4 after carbonate depletion, resulting in an increase in acid-soluble elements, including Cu and Zn. With the dissolution of Al-bearing minerals, the pH stabilized above 4, and sulfide oxidation continued to decline until the end of the experiment. The variation in activation energy of sulfide oxidation correlates with changes in sulfide availability, where the lowest activation energies occurred during the largest releases of SO4. A decrease in sulfide availability was attributed to consumption of sulfide and weathered rims on sulfide grains that reduced the oxidation rate. Varying element release rates due to changing carbonate and sulfide availability provide identifiable geochemical conditions that can be viewed as neutralization sequences and may be extrapolated to the field site for examining the evolution of mineral weathering of the waste rock.

  10. Performance of an open limestone channel for treating a stream affected by acid rock drainage (León, Spain).

    Science.gov (United States)

    Santofimia, Esther; López-Pamo, Enrique

    2016-07-01

    The generation of acid rock drainage (ARD) was observed after the oxidation dissolution of pyrite-rich black shales, which were excavated during the construction of a highway in León (Spain). ARDs are characterized by the presence of high concentrations of sulfate and metals (Al, Fe, Mn, Zn, Cu, Co, Ni, Th, and U) that affect the La Silva stream. Dissolved element concentrations showed values between one and four orders of magnitude higher than those of natural waters of this area. A passive treatment system was constructed; the aim of which was to improve the quality of the water of the stream. This work provides a hydrochemical characterization of the La Silva stream after its transit through the different elements that constitute the passive treatment system (open limestone channel (OLC), small ponds, and a wetland), during its first year of operation. The passive treatment system has two sections separated by a tunnel 230 m long. The first section, which stretches between the highway and the tunnel entrance, is an OLC 350 m long with a slope of 16 %. The second section, which stretches from the tunnel exit to the end wetland, has a length of 700 m and a slope of 6 %; it is in this section where six small ponds are located. In the first section of this passive treatment system, the OLC was effectively increasing the pH from 3 to 4-4.5 and eliminating all of the dissolved Fe and the partially dissolved Al. These elements, after hydrolysis at a pH 3-3.5 and 4-4.5, respectively, had precipitated as schwertmannite and hydrobasaluminite, while other dissolved metals were removed totally or partially for adsorption by the precipitates and/or by coprecipitation. The second section receives different inputs of water such as ARDs and natural waters. After exiting the treatment system, the stream is buffered by Al at a pH of 4-4.3, showing high Al concentrations (19-101 mg/L) but with a complete removal of dissolved Fe. Unfortunately, the outflow shows similar or

  11. Thermochemical Kinetics of H2O and HNO3 on crystalline Nitric Acid Hydrates (alpha-, beta-NAT, NAD) in the range 175-200 K

    Science.gov (United States)

    Rossi, Michel J.; Iannarelli, Riccardo

    2015-04-01

    The growth of NAT (Nitric Acid Trihydrate, HNO3x3H2O) and NAD (Nitric Acid Dihydrate, HNO3x2H2O) on an ice substrate, the evaporative lifetime of NAT and NAD as well as the interconversion of alpha- and beta-NAT competing with evaporation and growth under UT/LS conditions depends on the interfacial kinetics of H2O and HNO3 vapor on the condensed phase. Despite the existence of some literature results we have embarked on a systematic investigation of the kinetics using a multidiagnostic experimental approach enabled by the simultaneous observation of both the gas (residual gas mass spectrometry) as well as the condensed phase (FTIR absorption in transmission). We report on thermochemically consistent mass accommodation coefficients alpha and absolute evaporation rates Rev/molecule s-1cm-3 as a function of temperature which yields the corresponding vapor pressures of both H2O and HNO3 in equilibrium with the crystalline phases, hence the term thermochemical kinetics. These results have been obtained using a stirred flow reactor (SFR) using a macroscopic pure ice film of 1 micron or so thickness as a starting substrate mimicking atmospheric ice particles and are reported in a phase diagram specifically addressing UT (Upper Troposphere)/LS (Lower Stratosphere) conditions as far as temperature and partial pressures are concerned. The experiments have been performed either at steady-state flow conditions or in transient supersaturation using a pulsed solenoid valve in order to generate gas pulses whose decay were subsequently monitored in real time. Special attention has been given to the effect of the stainless-steel vessel walls in that Langmuir adsorption isotherms for H2O and HNO3 have been used to correct for wall-adsorption of both probe gases. Typically, the accommodation coefficients of H2O and HNO3 are similar throughout the temperature range whereas the rates of evaporation Rev of H2O are significantly larger than for HNO3 thus leading to the difference in

  12. Zinc isotope investigation of surface and pore waters in a mountain watershed impacted by acid rock drainage

    International Nuclear Information System (INIS)

    The pollution of natural waters with metals derived from the oxidation of sulfide minerals like pyrite is a global environmental problem. However, the metal loading pathways and transport mechanisms associated with acid rock drainage reactions are often difficult to characterize using bulk chemical data alone. In this study, we evaluated the use of zinc (Zn) isotopes to complement traditional geochemical tools in the investigation of contaminated waters at the former Waldorf mining site in the Rocky Mountains, Colorado, U.S.A. Geochemical signatures and statistical analysis helped in identifying two primary metal loading pathways at the Waldorf site. The first was characterized by a circumneutral pH, high alkalinity, and high Zn/Cd ratios. The second was characterized by acidic pHs and low Zn/Cd ratios. Zinc isotope signatures in surface water samples collected across the site were remarkably similar (the δ66Zn, relative to JMC 3-0749-L, for most samples ranged from 0.20 to 0.30‰ ± 0.09‰ 2σ). This probably suggests that the ultimate source of Zn is consistent across the Waldorf site, regardless of the metal loading pathway. The δ66Zn of pore water samples collected within a nearby metal-impacted wetland area, however, were more variable, ranging from 0.20 to 0.80‰ ± 0.09‰ 2σ. Here the Zn isotopes seemed to reflect differences in groundwater flow pathways. However, a host of secondary processes might also have impacted Zn isotopes, including adsorption of Zn onto soil components, complexation of Zn with dissolved organic matter, uptake of Zn into plants, and the precipitation of Zn during the formation of reduced sulfur species. Zinc isotope analysis proved useful in this study; however, the utility of this isotopic tool would improve considerably with the addition of a comprehensive experimental foundation for interpreting the complex isotopic relationships found in soil pore waters. - Highlights: ► Zinc isotopes of water were measured in samples

  13. ADVANCES IN LIQUID CRYSTALLINE POLYESTERS

    Institute of Scientific and Technical Information of China (English)

    W. J. Jackson

    1992-01-01

    Advances have been made in understanding the interactions of composition, molecular weight,liquid crystallinity, orientation, and three-dimensional crystallinity on the properties of injection-molded and melt-spun liquid crystalline polyesters (LCP's). Two classes of potentially low-cost LCP's were compared : (1) semiflexible LCP's prepared from 1,6-hexanediol and the dimethyl ester of either trans-4, 4'-stilbenedicarboxylic acid or 4.4 ′-biphenyldicarboxylic acid and (2) all-aromatic LCP's prepared from terephthalic acid, 2, 6-naphthalenedicarboxylic acid, the diacetate of hydroquinone,and the acetate of p-hydroxybenzoic acid. The effects of composition on the plastic properties of the 4-component all-aromatic LCP's were determined with the aid of a 3 × 3 factorial statistically designed experiment, the generation of equations with a computer program, and the plotting of three-dimensional figures and contour diagrams. The effects of absolute molecular weight (Mw) on the tensile strengths of the semiflexible LCP's and one of the all-aromatic LCP's having an excellent balance of plastic properties were also compared, and it was observed that the semiflexible LCP's required Mw's about 4 times higher than the all-aromatic LCP to attain a given strength. Persistence lengths and molecular modeling were used to explain these differences.

  14. Crystalline and Crystalline International Disposal Activities

    Energy Technology Data Exchange (ETDEWEB)

    Viswanathan, Hari S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Chu, Shaoping [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Reimus, Paul William [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Makedonska, Nataliia [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hyman, Jeffrey De' Haven [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Karra, Satish [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dittrich, Timothy M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-12-21

    This report presents the results of work conducted between September 2014 and July 2015 at Los Alamos National Laboratory in the crystalline disposal and crystalline international disposal work packages of the Used Fuel Disposition Campaign (UFDC) for DOE-NE’s Fuel Cycle Research and Development program.

  15. Approaches to confirmatory testing of a groundwater flow model for sparsely fractured crystalline rock, exemplified by data from the proposed high-level nuclear waste repository site at Forsmark, Sweden

    Science.gov (United States)

    Follin, Sven; Hartley, Lee

    2014-03-01

    The Svensk Kärnbränslehantering AB (SKB) has proposed the Forsmark site as a future repository for spent high-level nuclear fuel, involving disposal at about 470 m depth in sparsely fractured crystalline bedrock. An essential part of the completed inter-disciplinary site investigation was to develop an integrated account of the site and its regional setting, including the current state of the geosphere and the biosphere as well as natural processes affecting long-term evolution. First, this report recollects the integrated understanding and some key hydraulic characteristics of the crystalline bedrock at Forsmark along with a description of the flow model set-up and the methodology used for paleoclimatic flow modeling. Second, the protocol used for site-scale groundwater flow and solute transport modeling is demonstrated. In order to conduct a quantitative assessment of groundwater flow paths at Forsmark, the standard guide for groundwater flow modeling was elaborated on, to support both discrete and porous media flow approaches. In total, four independent types of data were used to confirm that the final groundwater flow model for the crystalline bedrock was representative of site conditions.

  16. Long-term field evaluation of phosphate rock and superphosphate use strategies in acid soils of Hungary: Two comparative field trials

    Energy Technology Data Exchange (ETDEWEB)

    Nemeth, T. [Research Institute for Soil Science and Agricultural Chemistry of the Hungarian Academy of Sciences, Budapest (Hungary)]. E-mail: t_nemeth@rissac.hu; Magyar, M.; Csatho, P.; Osztoics, E.; Baczo, G. [Research Institute for Soil Science and Agricultural Chemistry of the Hungarian Academy of Sciences, Budapest (Hungary); Hollo, S. [Kompolt Research Institute of Szent Istvan University, Godollo (Hungary); Nemeth, I. [Faculty of Georgikon Agricultural Sciences, University of Veszprem, Keszthely (Hungary)

    2002-05-15

    The effect of two P-forms and the P fertilization system were studied in field trials set up on two moderately acidic Hungarian soils. Reactive Algerian rock phosphate and Kola superphosphate doses were based on the phosphorus equivalence. The experimental design makes it possible to compare the effect of annual 35 kg/ha P doses with initial one-time application of the 175 kg/ha P level in a five-year interval. Ammonium-lactate (AL)-, NaHCO{sub 3} (Olsen)- and DW-P contents as well as Lakanen- Ervio (LE)- soluble Cd, Cr and Sr contents were also determined. The results of the first five-year period are reported in the paper. Responses to P fertilization were related to the original P supply of the soils. There was no significant difference between the two P forms and between the P fertilization systems on both grain yield and P-uptake. While AL- method overestimated, and Olsen-method - on the other hand - underestimated the P supply of reactive Algerian rock phosphate, distilled water (DW)-soluble P contents indicated the soil P status more accurately. Phosphorus balances were positive after the fifth year of the trials in the P treated plots. The soluble Cd and Cr contents did not increase in the Algerian rock phosphate treated plots. On the other hand, Kola superphosphate application at 175 kg/ha P level resulted in higher LE-Sr contents in soils. The Algerian rock phosphate is an economic alternative P source on the moderately or strongly acidic Hungarian soils. (author)

  17. 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.

  18. 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.

  19. Carborane-containing liquid-crystalline polycrylates

    International Nuclear Information System (INIS)

    Carborane-containing homo- and copolyarylates were prepared by acceptor-catalytic polyesterification in solution from m-carboranedicarboxylic acid and 4,4'-dioxydiphenyl-o-carborane in combination with common dicarboxylic acids and bisphenols. The properties of the resulting polyarylates were studied, and the factors affecting the development of liquid-crystalline order in carborane-containing copolyarylates were discussed

  20. Development of grouting technologies for geological disposal of high level waste in Japan. 1. Preliminary study for in-situ grout injection test in crystalline rock mass test site

    International Nuclear Information System (INIS)

    Grouting technology is fundamental to the safe and efficient construction of underground facilities for the geological disposal of High Level Waste in Japan. The Japan Atomic Energy Agency has been developing grouting materials and technologies with consideration to the long term chemical interactions between the grout material and the natural barrier rock mass. An in-situ grout injection test has been carried out at the Grimsel Test Site to optimize grouting design. This report is for the in-situ grout injection test plan and the result of the preliminary study. (author)

  1. 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…

  2. 盐酸浓度对酸解玉米淀粉结晶结构和性能的影响%Effects of hydrochloric acid concentration on crystalline structure and properties of corn starch

    Institute of Scientific and Technical Information of China (English)

    左迎峰; 张彦华; 杨龙; 谭海彦; 顾继友

    2013-01-01

    以玉米淀粉为原料,用盐酸对其酸解制备酸解玉米淀粉.考虑盐酸浓度对酸解玉米淀粉结构和性能的影响.通过抽滤洗涤法、X射线衍射(XRD)、旋转粘度计、差示扫描量热法(DSC)和热重分析(TGA)对酸解淀粉的回收率、结晶度、糊化粘度、糊化温度和热性能进行分析.结果表明,酸解玉米淀粉的回收率、结晶度和糊化温度随盐酸浓度的增大,先增大后减小,盐酸浓度为0.5 mol/L时,回收率、结晶度和糊化温度都达到最大值;糊化粘度随盐酸浓度的增大而迅速减小;酸解改性对玉米淀粉的热稳定性影响较小.%Acid hydrolysis corn starch was prepared by hydrochloric acid method to study the effects of hydrochloric acid concentrations on the structure and properties of acid hydrolysis com starch.. The crystallinity, gelatinization viscosity, gelatinization temperature and thermal performance of acid hydrolysis starch were analyzed by using filtration washing method, X-ray diffraction, rotational viscometer, differential scanning calorimetry and thermo gravimetric analysis, respectively. The results show that the recovery yield, crystallinity and gelatinization temperature increased first and then decreased with the increase of hydrochloric acid concentration, and reached the maximum values when hydrochloric acid concentration was 0.5 mol/L; the gelatinization viscosity rapidly decreased with increase of hydrochloric acid concentration. So the acid modification had small effect on thermal stability of corn starch.

  3. Crystalline Silica Primer

    Science.gov (United States)

    ,

    1992-01-01

    Crystalline silica is the scientific name for a group of minerals composed of silicon and oxygen. The term crystalline refers to the fact that the oxygen and silicon atoms are arranged in a threedimensional repeating pattern. This group of minerals has shaped human history since the beginning of civilization. From the sand used for making glass to the piezoelectric quartz crystals used in advanced communication systems, crystalline silica has been a part of our technological development. Crystalline silica's pervasiveness in our technology is matched only by its abundance in nature. It's found in samples from every geologic era and from every location around the globe. Scientists have known for decades that prolonged and excessive exposure to crystalline silica dust in mining environments can cause silicosis, a noncancerous lung disease. During the 1980's, studies were conducted that suggested that crystalline silica also was a carcinogen. As a result of these findings, crystalline silica has been regulated under the Occupational Safety and Health Administration's (OSHA) Hazard Communication Standard (HCS). Under HCS, OSHAregulated businesses that use materials containing 0.1% or more crystalline silica must follow Federal guidelines concerning hazard communication and worker training. Although the HCS does not require that samples be analyzed for crystalline silica, mineral suppliers or OSHAregulated

  4. Phosphorus fertility recapitalization of nutrient-depleted tropical acid soils with reactive phosphate rock: An assessment using the isotopic exchange technique

    Energy Technology Data Exchange (ETDEWEB)

    Fardeau, J.-C. [INRA, Departement Environnement et Agronomie, Versailles (France)]. E-mail: fardeau@versailles.inra.fr; Zapata, F. [IAEA, Soil and Water Management and Crop Nutrition Section, Joint FAO/IAEA Programme, Vienna (Austria)

    2002-05-15

    A 'soil P fertility recapitalization' initiative utilizing large rates of phosphate rocks (PRs) was proposed to improve the soil P status and increase the sustainable food production in acid and P-deficient tropical soils. Two series of experiments were carried out using five tropical acid soils treated with heavy applications of Gafsa phosphate rock (GPR). In the first series, the soils were mixed with GPR at the following application rates: 0, 500, 1000 and 2000 mg P{center_dot}kg{sup -1}, and incubated for one month in moist conditions. In another series, 1000 mg P kg{sup -1} applied as GPR was added to three soils and incubated for 1.5 month; thereafter 50 mg P kg{sup -1} as triple superphosphate (TSP) were added. The {sup 32}P isotopic exchange method was utilized to assess the contribution of GPR to the available soil P. Changes in amounts, E, of P transferred with time as phosphate ions from the soil particles to the soil solution as well as changes in pH, calcium and phosphate concentrations in soil suspensions were determined. It was found that: (i) the contribution of P from GPR to recapitalization of soil P fertility was mainly assessed by E pool size, pH, calcium and phosphate concentrations; other variables were not significant at the 0.1 level; (ii) heavy applications of GPR did not saturate all the P sorption sites, P freshly applied as water-soluble P was still sorbed; (iii) recapitalization of soil P fertility using GPR was partly obtained in some acid tropical soils; (iv) Upon dissolution, GPR provided calcium ions to crops and to soils, thus reducing Al toxicity, but its liming effect was limited. To explain these effects with heavy application rates of GPR, it was postulated that a coating of Al and Fe compounds is formed around PR particles with time, thus reducing further dissolution. (author)

  5. Effects of low molecular weight organic acids on the immobilization of aqueous Pb(II) using phosphate rock and different crystallized hydroxyapatite.

    Science.gov (United States)

    Wei, Wei; Cui, Jing; Wei, Zhenggui

    2014-06-01

    Understanding the effects of low molecular weight organic acids (LMWOAs) on the transformation of Pb(II) to geochemically stable pyromorphite (PY) by apatite materials (AMs), has considerable benefits for risk assessment and remediation strategies for contaminated water and soil. In this study, we systematically investigated the immobilization of Pb(II) from aqueous solution by natural phosphate rock (PR) and different crystallized hydroxyapatite (HAp) in the absence and presence of LMWOAs (oxalic, malic and citric acids). The results indicated that the effectiveness of PR and HAp in immobilizing Pb(II) followed in descending order by HAp2 (the poorly crystallized HAp), HAp1 (the well crystallized HAp) and PR, regardlessof the presence of LMWOAs. The presence of malic and citric acids significantly decreased the immobilizationefficiency of Pb(II) by HAp1 and PR, clarifying the lower adsorption affinities of Pb(II)-organic acid complexes on HAp1 and PR rather than Pb(II) ion. On thecontrary, oxalic acid could markedly enhance the removal of Pb(II) from aqueous solution by HAp1 and PR through the formation of lead oxalate, which was confirmed by FT-IR and XRDanalysis. Results also showed that LMWOAs had little promoting or inhibiting effect on the immobilization of Pb(II) by HAp2. This study suggested that the ubiquity of LMWOAs in natural environments could retard the transformation efficiency of Pb(II) to PY by AMs, especiallyin thepresenceof oxalic acid, and the poorly crystallized HAp2 had great potential to remediate Pb(II)-contaminated water and soil due to its insusceptibility to LMWOAs.

  6. Treated and untreated rock dust: Quartz content and physical characterization.

    Science.gov (United States)

    Soo, Jhy-Charm; Lee, Taekhee; Chisholm, William P; Farcas, Daniel; Schwegler-Berry, Diane; Harper, Martin

    2016-11-01

    Rock dusting is used to prevent secondary explosions in coal mines, but inhalation of rock dusts can be hazardous if the crystalline silica (e.g., quartz) content in the respirable fraction is high. The objective of this study is to assess the quartz content and physical characteristics of four selected rock dusts, consisting of limestone or marble in both treated (such as treatment with stearic acid or stearates) and untreated forms. Four selected rock dusts (an untreated and treated limestone and an untreated and treated marble) were aerosolized in an aerosol chamber. Respirable size-selective sampling was conducted along with particle size-segregated sampling using a Micro-Orifice Uniform Deposit Impactor. Fourier Transform Infrared spectroscopy and scanning electron microscopy with energy-dispersive X-ray (SEM-EDX) analyses were used to determine quartz mass and particle morphology, respectively. Quartz percentage in the respirable dust fraction of untreated and treated forms of the limestone dust was significantly higher than in bulk samples, but since the bulk percentage was low the enrichment factor would not have resulted in any major change to conclusions regarding the contribution of respirable rock dust to the overall airborne quartz concentration. The quartz percentage in the marble dust (untreated and treated) was very low and the respirable fractions showed no enrichment. The spectra from SEM-EDX analysis for all materials were predominantly from calcium carbonate, clay, and gypsum particles. No free quartz particles were observed. The four rock dusts used in this study are representative of those presented for use in rock dusting, but the conclusions may not be applicable to all available materials. PMID:27314444

  7. Crystallins of the octopus lens. Recruitment from detoxification enzymes.

    Science.gov (United States)

    Tomarev, S I; Zinovieva, R D; Piatigorsky, J

    1991-12-15

    The eye lens crystallins of the octopus Octopus dofleini were identified by sequencing abundant proteins and cDNAs. As in squid, the octopus crystallins have subunit molecular masses of 25-30 kDa, are related to mammalian glutathione S-transferases (GST), and are encoded in at least six genes. The coding regions and deduced amino acid sequences of four octopus lens cDNAs are 75-80% identical, while their non-coding regions are entirely different. Deduced amino acid sequences show 52-57% similarity with squid GST-like crystallins, but only 20-25% similarity with mammalian GST. These data suggest that the octopus and squid lens GST-like crystallin gene families expanded after divergence of these species. Northern blot hybridization indicated that the four octopus GST-like crystallin genes examined are lens-specific. Lens extracts showed about 40 times less GST activity using 1-chloro-2,4-dinitrobenzene as substrate than liver extracts of the octopus, indicating that the major GST-like crystallins are specialized for a lens structural role. A prominent 59-kDa crystallin polypeptide, previously observed in octopus but not squid and called omega-crystallin (Chiou, S.-H. (1988) FEBS Lett. 241, 261-264), has been identified as an aldehyde dehydrogenase. Since cytoplasmic aldehyde dehydrogenase is a major protein in elephant shrew lenses (eta-crystallin; Wistow, G., and Kim, H. (1991) J. Mol. Evol. 32, 262-269) the octopus aldehyde dehydrogenase crystallin provides the first example of a similar enzyme-crystallin in vertebrates and invertebrates. The use of detoxification stress proteins (GST and aldehyde dehydrogenase) as cephalopod crystallins indicates a common strategy for recruitment of enzyme-crystallins during the convergent evolution of vertebrate and invertebrate lenses. For historical reasons we propose that the octopus GST-like crystallins, like those of the squid, are called S-crystallins. PMID:1721068

  8. Crystalline Repository Project. Technical progress report, October 1982-March 1983

    International Nuclear Information System (INIS)

    This document reports the progress being made periodically on the development of a geologic repository in crystalline rock for the permanent disposal of high-level nuclear waste. The reporting elements are arranged by the work breakdown structure so that related studies are presented together. The studies are reported by the Office of Crystalline Respository Development (OCRD), a prime contractor of the US Department of Energy Repository Project Office. The studies include work by other prime contractors and by subcontractors to OCRD

  9. Exploration of remediation of acid rock drainage with clinoptilolite as sorbent in a slurry bubble column for both heavy metal capture and regeneration.

    Science.gov (United States)

    Cui, Heping; Li, Loretta Y; Grace, John R

    2006-10-01

    Preliminary work was carried out to explore a novel process for high-efficiency high-capacity remediation of acid rock drainage. Zn and other metal ions were adsorbed and desorbed in a laboratory Plexiglas slurry bubble column with natural clinoptilolite particles as sorbent. The results indicate that both adsorption and desorption in this medium have considerable advantages over those in the packed beds and rotating columns, leading to faster batch adsorption and desorption, as well as greater uptake of zinc. The adsorption order of clinoptilolite particles to different metal ions appeared to be Fe>Al>Cu>Zn>Mg>Mn on the basis of normalized concentrations. Smaller particles had significantly higher capacity and rates of the adsorption than larger particles for the same operating conditions. PMID:16962631

  10. Fractionation of Cu and Zn isotopes during adsorption onto amorphous Fe(III) oxyhydroxide: Experimental mixing of acid rock drainage and ambient river water

    Science.gov (United States)

    Balistrieri, L.S.; Borrok, D.M.; Wanty, R.B.; Ridley, W.I.

    2008-01-01

    Fractionation of Cu and Zn isotopes during adsorption onto amorphous ferric oxyhydroxide is examined in experimental mixtures of metal-rich acid rock drainage and relatively pure river water and during batch adsorption experiments using synthetic ferrihydrite. A diverse set of Cu- and Zn-bearing solutions was examined, including natural waters, complex synthetic acid rock drainage, and simple NaNO3 electrolyte. Metal adsorption data are combined with isotopic measurements of dissolved Cu (65Cu/63Cu) and Zn (66Zn/64Zn) in each of the experiments. Fractionation of Cu and Zn isotopes occurs during adsorption of the metal onto amorphous ferric oxyhydroxide. The adsorption data are modeled successfully using the diffuse double layer model in PHREEQC. The isotopic data are best described by a closed system, equilibrium exchange model. The fractionation factors (??soln-solid) are 0.99927 ?? 0.00008 for Cu and 0.99948 ?? 0.00004 for Zn or, alternately, the separation factors (??soln-solid) are -0.73 ?? 0.08??? for Cu and -0.52 ?? 0.04??? for Zn. These factors indicate that the heavier isotope preferentially adsorbs onto the oxyhydroxide surface, which is consistent with shorter metal-oxygen bonds and lower coordination number for the metal at the surface relative to the aqueous ion. Fractionation of Cu isotopes also is greater than that for Zn isotopes. Limited isotopic data for adsorption of Cu, Fe(II), and Zn onto amorphous ferric oxyhydroxide suggest that isotopic fractionation is related to the intrinsic equilibrium constants that define aqueous metal interactions with oxyhydroxide surface sites. Greater isotopic fractionation occurs with stronger metal binding by the oxyhydroxide with Cu > Zn > Fe(II).

  11. The Alteration History of Clovis Class Rocks in Gusev Crater as Determined by Ti-Normalzed Mass Balance Analysis

    Science.gov (United States)

    Sutter, Brat; Ming, Douglas W.; Niles, P. B.; Golden, D. C.

    2012-01-01

    The West Spur Clovis class rocks in Gusev Crater are some of the most altered rocks in Gusev Crater and likely contain a mixed sulfate and phyllosilicate mineralogy [1,2]. The high S and Cl content of the Clovis rocks suggests that acidic vapors or fluids of H2SO4 and HCl reacted with the Clovis parent rock to form Ca, Mg,- sulfates, iron-oxyhydroxides and secondary aluminosilicates (approx.60 wt.%) of a poorly crystalline nature (e.g., allophane) [1]. Up to 14-17 wt.% phyllosilicates (e.g., kaolinite, chlorite, serpentine) are hypothesized to exist in the Clovis materials suggesting that Clovis parent materials while possibly exposed to acidic pHs were likely neutralized by basalt dissolution which resulted in mildly acidic pHs (4-6) [1, 2]. This work proposes that subsequent to the alteration of the Clovis rocks, alteration fluids became concentrated in ions resulting in the addition of silicate and salts. The objective of this work is to utilize Ti-normalized mass balance analysis to evaluate (1) mineral gains and losses and (2) elemental gains and losses in the Clovis rocks. Results of this work will be used evaluate the nature of geochemical conditions that affect phyllosilicate and sulfate formation at Gusev crater.

  12. Preferential Incorporation of Azelaic Acid Units into the Crystalline Phase of the Copoly(Alkylene Dicarboxylate Derived from 1,9-Nonanediol and an Equimolar Mixture of Pimelic and Azelaic Acids

    Directory of Open Access Journals (Sweden)

    Angélica Díaz

    2015-09-01

    Full Text Available The crystalline structure of two biodegradable odd-odd polyesters (i.e., poly(nonamethylene pimelate (PES 9,7 and poly(nonamethylene azelate (PES 9,9 was investigated by means of electron and X-ray diffraction of single crystals and oriented fibers, respectively. Truncated rhombic crystals were obtained with an aspect ratio that was strongly depended on the supercooling degree. The crystalline structure of both homopolyesters was defined by an orthorhombic P21ab space group and a large unit cell containing four molecular segments with an all-trans conformation. Nevertheless, the structure in the chain axis projection was equivalent to a simpler cell containing only two segments. Crystalline lamellae were effectively degraded by lipases, starting the enzymatic attack on the lamellar surfaces. The random copolymer constituted by an equimolar amount of pimelate and azelate units (COPES 9,7/9 crystallized according to regular lamellae with a similar molecular arrangement in the chain axis projection. The structure of this copolymer was preferably conditioned by the azelate component as could be deduced from both, diffraction and spectroscopic data. Analysis of small angle X-ray scattering patterns pointed out that less crystalline lamellae with higher amorphous thickness had developed in the copolymer. This feature was interpreted as a consequence of the preferential incorporation of pimelate comonomer units in the folding surface.

  13. What Is Crystalline Silica?

    Science.gov (United States)

    ... 1926.55, 1910.1000). OSHA also requires hazard communication training for workers exposed to crystalline silica, and ... identify, reduce, and eliminate health hazards associated with occupational ... safety and health? OSHA has various publications, standards, technical ...

  14. Petrology, Magnetic susceptibility, Tectonic setting and mineralization associated with Plutonic and Volcanic Rocks, Eastern Bajestan and Taherabad, Iran

    Directory of Open Access Journals (Sweden)

    Malihe Ghoorchi

    2009-09-01

    Full Text Available Study area is located in district of Bajestan and Ferdows cities, NE of Iran. Structurally, this area is part of Lut block. The oldest exposed rocks, to the north of intrusive rocks and in Eastern Bajestan, are meta-chert, slate, quartzite, thin-bedded crystalline limestone and meta-argillite. The sedimentary units are: Sardar Formation (Carboniferous, Jamal Formation (Permian, Sorkh Shale and Shotori Formations (Triassic, carbonateous rocks (Cretaceous and lithostratigraphically equivalent to Kerman conglomerate (Cretaceous-Paleocene are exposed in this area. Based on relative age, magmatism in eastern Bajestan and Taherabad started after Late Cretaceous and it has been active and repeated during Tertiary time. At least, three episodes of volcanic activities are recognized in this area. The first stage was mainly volcanic flow with mafic composition and minor intermediate. The second episode was mainly intermediate in composition. The third stage was changed to acid-intermediate in composition. Since the plutonic rocks intruded the volcanic rocks, therefore they may be Oligo-Miocene age. Bajestan intrusive rocks are granite-granodiorite-quartz monzonite. Taherabad intrusive rocks are diorite-quartz diorite- monzonite-latite. Bajestan intrusive rocks are reduced type (ilmenite series and Taherabad intrusive rocks are oxidized type (magnetite series.Based on geochemical analysis including trace elements, REE and isotopic data, Bajestan intrusive rocks formed in continental collision zone and the magma has crustal origin. Taherabad intrusive rocks were formed in subduction zone and magma originated from oceanic crust. Taherabad intrusive rock has exploration potential for Cu-Au and pb.

  15. 低结晶度聚ε-己内酯电纺膜的制备及其药物控释行为%CONTROLLED RELEASE OF SALICYLIC ACID FROM ELECTROSPUN MATS OF POLY(ε-CAPROLACTONE) WITH LOW CRYSTALLINITY

    Institute of Scientific and Technical Information of China (English)

    彭慧; 陶鑫峰; 凌君

    2011-01-01

    With the purpose to decrease the crystallinity of poly (ε-caprolactone) (PCL), a small amount (8.5 mol% ) of 2,2-dimethyltrimethylene carbonate (DTC) was added to copolymerize with ε-caprolactone (CL) using lanthanum tris ( 2,6-di-tert-butyl-4-methylphenolate ) ( La (OAr) 3 ) as catalyst. The produced polyester P(CL-co-DTC) (PCD) was well-characterized by 1H-NMR, SEC, DSC and WAXS. The results showed random copolymer PCD was synthesized. DSC and WAXS results proved PCD had a much lower crystallinity (Xc = 28.1% ) compared to that of PCL (Xc = 44. 7% ). PCD, as well as PCL homopolymer containing 8 wt% salicylic acid as a model drug was electrospun into ultrafine fibers with the diameter around 1 μm and further submitted to in vitro drug release test. The results showed that the PCD electrospun mat exhibited a controlled drug-release behavior while the PCL one displayed a burst-release behavior. The DSC and WAXS results showed PCL electrospun fibers had a much higher crystallinity (Xc = 79.3% ) than that of PCD electrospun fibers (Xc = 40. 3% ) and this explained the difference of drug-release behaviors of the two electrospun mats. It was the non-crystalline domains involved in PCD that facilitated the compatibility between the polymer matrix and salicylic acid and allowed the drug to be released in a controlled way through the thermal motion of the polymer chain. This study provided a strategy for a better drug inclusion and release behavior by lowering the crystallinity of matrix material.%以芳氧基稀土三(2,6-二叔丁基-4-甲基苯氧基)镧(La(OAr)3)为催化剂,通过加入少量(8.5 mol%)碳酸2,2-二甲基三亚甲基酯(DTC)与ε-己内酯(CL)进行无规共聚合,成功制备了低结晶度的脂肪族内酯-碳酸酯无规共聚酯(PCD)材料,并用1H-NMR、SEC、DSC和WAXS证明了产物的结构和性能.以聚ε-己内酯(PCL)和PCD为基质、以水杨酸为模型药物,通过静电纺丝的方法制备了载药量为8 wt

  16. Effects of balancing crystalline amino acids in diets containing heat-damaged soybean meal or distillers dried grains with solubles fed to weanling pigs.

    Science.gov (United States)

    Almeida, F N; Htoo, J K; Thomson, J; Stein, H H

    2014-10-01

    Two experiments were conducted to investigate if adjustments in diet formulations either based on total analysed amino acids or standardized ileal digestible (SID) amino acids may be used to eliminate negative effects of including heat-damaged soybean meal (SBM) or heat-damaged corn distillers dried grains with solubles (DDGS) in diets fed to weanling pigs. In Experiment 1, four corn-SBM diets were formulated. Diet 1 contained non-autoclaved SBM (315 g/kg), and this diet was formulated on the basis of analysed amino acid concentrations and using SID values from the AminoDat® 4.0 database. Diet 2 was similar to Diet 1 in terms of ingredient composition, except that the non-autoclaved SBM was replaced by autoclaved SBM at 1 : 1 (weight basis). Diet 3 was formulated using autoclaved SBM and amino acid inclusions in the diet were adjusted on the basis of analysed total amino acid concentrations in the autoclaved SBM and published SID values for non-autoclaved SBM (AminoDat® 4.0). Diet 4 also contained autoclaved SBM, but the formulation of this diet was adjusted on the basis of analysed amino acids in the autoclaved SBM and SID values that were adjusted according to the degree of heat damage in this source of SBM. Pigs (160; initial BW: 10.4 kg) were allotted to the four treatments with eight replicate pens per treatment in a randomized complete block design. Diets were fed to pigs for 21 days. The gain to feed ratio (G : F) was greater (Pformulated using the concepts described for Experiment 1, except that heat-damaged DDGS, but not heat-damaged SBM, was used in the diets. Pigs fed Diet 1 had greater (Pformulation. Further research is needed to improve the prediction of the ileal digestibility of amino acids in heat-processed ingredients used in practical diet formulations.

  17. Hydrogen bonding and liquid crystallinity of low molar mass and polymeric mesogens containing benzoic acids: a variable temperature Fourier transform infrared spectroscopic study

    Science.gov (United States)

    Martínez-Felipe, A.; Cook, A. G.; Wallage, M. J.; Imrie, C. T.

    2014-12-01

    The phase behaviour and mesomorphism of poly(4-(6-propenoyloxyhexyloxy)benzoic acid) (PPOHBA) and 4-pentyloxybenzoic acid (POBA) is studied using variable-temperature Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction. PPHOBA exhibits a smectic C phase and POBA, a nematic phase. The temperature dependence of the Fermi resonance bands associated with the hydroxyl groups and of the carbonyl stretching region in the FTIR spectra indicates that there is a dynamic equilibrium between monomers and open and closed dimers formed by hydrogen bonding between benzoic acid moieties. The nematic phase observed for POBA is linked to the anisotropic cyclic dimer, while an abrupt increase in the concentration of monomer drives isotropisation. In PPOHBA, hydrogen-bonded supramesogens promote smectic behaviour, while hydrogen-bonded crosslinks stabilise the lamellae. The increased viscosity arising from this dynamic crosslinking is offset by the flexibility of the acrylate backbone and alkyl spacers.

  18. Study on the Recovery Process of Mycophenolic Acid from Mother Liquor of Crude Crystalline%霉酚酸粗品结晶母液回收工艺研究

    Institute of Scientific and Technical Information of China (English)

    石磊

    2011-01-01

    OBJECTIVE To establish a recovery process for mycophenolic acid from mother liquor of crude crystalline. METHODS First, mycophenolic acid was transformed into the form of water-soluble salt by sodium hydroxide solution. Then mycophenolic acid was separated from the solution by macroporous resin D312. RESULTS The yield of transformation was over 90%. The overall yield of mycophenolic acid was increased by 10% , and product's quality met the standards. CONCLUSION This process has the advantages of high yield and low cost, so it is satisfactory and provides a new thread for the industrial production of mycophenolic acid.%目的 建立霉酚酸粗品结晶母液有效成分的回收工艺.方法 根据霉酚酸的化学特性,先用NaOH水溶液改变结晶母液pH,使霉酚酸从结晶母液中转化成易溶于水的相应盐,再采用大孔吸附树脂D312作为吸附剂从溶液中提取富集霉酚酸.结果 霉酚酸转化为钠盐收率在90%以上.回收工艺使提取总收率提高了10%以上,产品质量符合要求.结论 霉酚酸结晶母液回收工艺在提高总收率和降低生产成本上操作可行.该工艺具有工业参考的价值,为企业生产提供了一条新思路.

  19. Exploration of the crystalline underground by extension drilling of the Urach 3 well in the framework of a feasibility study for a hot dry rock demonstration project; Erkundung des kristallinen Untergrunds mit der Vertiefungsbohrung Urach 3 im Rahmen einer Machbarkeitsstudie fuer ein Hot-Dry-Rock-Demonstrationsprojekt

    Energy Technology Data Exchange (ETDEWEB)

    Tenzer, H. [Stadtwerke Bad Urach (Germany); Genter, A.; Hottin, A.M. [BRGM/GIG, Orleans (France)

    1997-12-01

    The prerequisites for specific research into the use of Hot Dry Rock geothermal energy at great depths and temperatures of up to 147 C. In Europe were created with the drilling and completition of the 3334 m deep research drill hole Urach 3 in its phase I (1977/78), and its subsequent extension to 3488 m in phase II (1982/83) within the metamorphic gneiss rock of Urach. A single hole circulation system was tested. Basic results concerning the temperature field, joint system, stress field and hydraulic behavior of the rock were achieved. According to the European HDR guidelines data from depths were a mean reservoir temperature of 175-180 C prevails were necessary to carry out a HDR pilot project. Within the scope of a feasibility study the already existing drill hole Urach 3 was extended from 3488 m to 4445 m depth where the required rock temperature of >170 C was expected. The objective of the project was to determine rock parameters at depth of high temperatures. The bottom hole temperature at true vertical depth of 4394.72 m was determined with 170 C. It can be proved that the temperature gradient is constant with 2.9 K/100 m depth. Due to the results of the investigations it is proposed that the Urach site located in a widespread tectonic horizontal strike-slip system is suitable for a HDR demonstration project. The results can be applied in south German and northern Swiss regions and in other large regions of Europe. Many potential consumers of geothermal energy produced by the HDR concept are situated close around the Urach 3 drill site. (orig./AKF) [Deutsch] Die Forschungsarbeiten zur Weiterentwicklung des Hot-Dry-Rock-Verfahrens begannen am Standort Bad Urach im Jahr 1975. In einer ersten Phase wurde die Bohrung Urach 3 1977/78 auf 3334 m mit einer Gesteinstemperatur von 143 C abgeteuft. Umfangreiche Hydraulische Tests und Frac-Versuche erfolgten. Hiermit wurden die Voraussetzungen fuer die Erkundung des Hot-Dry-Rock-Konzeptes in grossen Tiefen und

  20. Characterization of anthropogenic and natural sources of acid rock drainage at the Cinnamon Gulch abandoned mine land inventory site, Summit County, Colorado

    Science.gov (United States)

    Bird, D.A.

    2003-01-01

    Colorado's Cinnamon Gulch releases acid rock drainage (ARD) from anthropogenic and natural sources. In 2001, the total discharge from Cinnamon Gulch was measured at 1.02 cfs (29 L/s) at base flow and 4.3 cfs (122 L/s) at high flow (spring runoff). At base flow, natural sources account for 98% of the discharge from the watershed, and about 96% of the chemical loading. At high flow, natural sources contribute 96% of discharge and 92 to 95% of chemical loading. The pH is acidic throughout the Cinnamon Gulch watershed, ranging from 2.9 to 5.4. At baseflow, nearly all of the trace metals analyzed in the 18 samples exceeded state hardness-dependent water quality standards for aquatic life. Maximum dissolved concentrations of selected constituents included 16 mg/ L aluminum, 15 mg/L manganese, 40 mg/L iron, 2 mg/L copper, 560 ??g/L lead, 8.4 mg/L zinc, and 300 mg/L sulfate. Average dissolved concentrations of selected metals at baseflow were 5.5 mg/L aluminum, 5.5 mg/L manganese, 14 ??g/L cadmium, 260 ??g/L copper, 82 ??g/L lead, and 2.8 mg/L zinc.

  1. Molecular aggregation in crystalline 1:1 complexes of hydrophobic D- and L-amino acids. I. The L-isoleucine series.

    Science.gov (United States)

    Dalhus; Görbitz

    1999-06-01

    The amino acid L-isoleucine has been cocrystallized with seven selected D-amino acids including D-methionine [L-isoleucine-D-methionine (1/1), C(6)H(13)NO(2).C(5)H(11)NO(2)S, amino-acid side chain R = -CH(2)-CH(2)-S-CH(3)] and a homologous series from D-alanine [L-isoleucine-D-alanine (1/1), C(6)H(13)NO(2).C(3)H(7)NO(2), R = -CH(3)] through D-alpha-aminobutyric acid [L-isoleucine-D-alpha-aminobutyric acid (1/1), C(6)H(13)NO(2).C(4)H(9)NO(2), R = -CH(2)-CH(3)] and D-norvaline [L-isoleucine-D-norvaline (1/1), C(6)H(13)NO(2).C(5)H(11)NO(2), R = -CH(2)-CH(2)-CH(3)] to D-norleucine [L-isoleucine-D-norleucine (1/1), C(6)H(13)NO(2).C(6)H(13)NO(2), R = -CH(2)-CH(2)-CH(2)-CH(3)] with linear side chains, and D-valine [L-isoleucine-D-valine (1/1), C(6)H(13)NO(2).C(5)H(11)NO(2), R = -CH-(CH(3))(2)] and D-leucine [L-isoleucine-D-leucine (1/1), C(6)H(13)NO(2).C(6)H(13)NO(2), R = -CH(2)-CH-(CH(3))(2)] with branched side chains. All the crystal structures are divided into distinct hydrophilic and hydrophobic layers. In the five complexes with amino acids with linear side chains the polar parts of the D- and L-amino acids are related by pseudo-glide-plane symmetry, and four of them have remarkably similar molecular arrangements. The D-valine and D-leucine complexes, on the other hand, are structurally quite different with the polar parts of the D- and L-amino acids related by pseudo-inversion. Differences in the hydrogen-bond pattern in the two molecular arrangements are discussed. PMID:10927385

  2. Molecular aggregation in selected crystalline 1:1 complexes of hydrophobic D- and L-amino acids. IV. The L-phenylalanine series.

    Science.gov (United States)

    Görbitz, Carl Henrik; Rissanen, Kari; Valkonen, Arto; Husabø, Asmund

    2009-06-01

    The amino acid L-phenylalanine has been cocrystallized with D-2-aminobutyric acid, C(9)H(11)NO(2).C(4)H(9)NO(2), D-norvaline, C(9)H(11)NO(2).C(5)H(11)NO(2), and D-methionine, C(9)H(11)NO(2).C(5)H(11)NO(2)S, with linear side chains, as well as with D-leucine, C(9)H(11)NO(2).C(6)H(13)NO(2), D-isoleucine, C(9)H(11)NO(2).C(6)H(13)NO(2), and D-allo-isoleucine, C(9)H(11)NO(2).C(6)H(13)NO(2), with branched side chains. The structures of these 1:1 complexes fall into two classes based on the observed hydrogen-bonding pattern. From a comparison with other L:D complexes involving hydrophobic amino acids and regular racemates, it is shown that the structure-directing properties of phenylalanine closely parallel those of valine and isoleucine but not those of leucine, which shares side-chain branching at C(gamma) with phenylalanine and is normally considered to be the most closely related non-aromatic amino acid.

  3. Molecular aggregation in selected crystalline 1:1 complexes of hydrophobic D- and L-amino acids. IV. The L-phenylalanine series.

    Science.gov (United States)

    Görbitz, Carl Henrik; Rissanen, Kari; Valkonen, Arto; Husabø, Asmund

    2009-06-01

    The amino acid L-phenylalanine has been cocrystallized with D-2-aminobutyric acid, C(9)H(11)NO(2).C(4)H(9)NO(2), D-norvaline, C(9)H(11)NO(2).C(5)H(11)NO(2), and D-methionine, C(9)H(11)NO(2).C(5)H(11)NO(2)S, with linear side chains, as well as with D-leucine, C(9)H(11)NO(2).C(6)H(13)NO(2), D-isoleucine, C(9)H(11)NO(2).C(6)H(13)NO(2), and D-allo-isoleucine, C(9)H(11)NO(2).C(6)H(13)NO(2), with branched side chains. The structures of these 1:1 complexes fall into two classes based on the observed hydrogen-bonding pattern. From a comparison with other L:D complexes involving hydrophobic amino acids and regular racemates, it is shown that the structure-directing properties of phenylalanine closely parallel those of valine and isoleucine but not those of leucine, which shares side-chain branching at C(gamma) with phenylalanine and is normally considered to be the most closely related non-aromatic amino acid. PMID:19498234

  4. Versatile supramolecular reactivity of zinc-tetra(4-pyridylporphyrin in crystalline solids: Polymeric grids with zinc dichloride and hydrogen-bonded networks with mellitic acid

    Directory of Open Access Journals (Sweden)

    Sophia Lipstman

    2009-12-01

    Full Text Available Crystal engineering studies confirm that the zinc-tetra(4-pyridylporphyrin building block reveals versatile supramolecular chemistry. In this work, it was found to be reactive in the assembly of both (a a 2D polymeric array by a unique combination of self-coordination and coordination through external zinc dichloride linkers and (b an extended heteromolecular hydrogen-bonded network with mellitic acid sustained by multiple connectivity between the component species.

  5. Liquid crystalline dihydroazulene photoswitches

    DEFF Research Database (Denmark)

    Petersen, Anne Ugleholdt; Jevric, Martyn; Mandle, Richard J.;

    2015-01-01

    A large selection of photochromic dihydroazulene (DHA) molecules incorporating various substituents at position 2 of the DHA core was prepared and investigated for their ability to form liquid crystalline phases. Incorporation of an octyloxy-substituted biphenyl substituent resulted in nematic...... phase behavior and it was possible to convert one such compound partly into its vinylheptafulvene (VHF) isomer upon irradiation with light when in the liquid crystalline phase. This conversion resulted in an increase in the molecular alignment of the phase. In time, the meta-stable VHF returns...... to the DHA where the alignment is maintained. The systematic structural variation has revealed that a biaryl spacer between the DHA and the alkyl chain is needed for liquid crystallinity and that the one aromatic ring in the spacer cannot be substituted by a triazole. This work presents an important step...

  6. Colloid properties in groundwaters from crystalline formations

    International Nuclear Information System (INIS)

    Colloids are present in all groundwaters. The role they may play in the migration of safety-relevant radionuclides in the geosphere therefore must be studied. Colloid sampling and characterisation campaigns have been carried out in Switzerland. On the bases of the results from studies in the Grimsel area, Northern Switzerland and the Black Forest, as well as those obtained by other groups concerned with crystalline waters, a consistent picture is emerging. The groundwater colloids in crystalline formations are predominantly comprised of phyllosilicates and silica originating from the aquifer rock. Under constant hydrogeochemical conditions, the colloid concentration is not expected to exceed 100 ng.ml-1 when the calcium concentration is greater than 10-4. However, under transient chemical or physical conditions, such as geothermal or tectonic activity, colloid generation may be enhanced and the colloid concentration may reach 10 μg.ml-1 or more, if both the calcium and sodium concentrations are low. In the Nagra Crystalline Reference Water the expected colloid concentration is -1. This can be compared, for example, to a colloid concentration of about 10 ng.ml-1 found in Zurzach water. The small colloid concentration in the reference water is a consequence of an attachment factor for clay colloids (monmorillonite) close to 1. A model indicates that at pH 8, the nuclide partition coefficients between water and colloid (Kp) must be smaller than 107 ml.g-1 if sorption takes place by surface complexation on colloids, = AIOH active groups forming the dominant sorption sites. This pragmatic model is based on the competition between the formation of nuclide hydroxo complexes in solution and their sorption on colloids. Experimental nuclide sorption data on colloids are compared with those obtained by applying this model. For a low colloid concentration, a sorption capacity of the order of 10-9 M and reversible surface complexation, their presence in the crystalline rock

  7. Estimation of the standardized ileal digestible valine to lysine ratio required for 25- to 120-kilogram pigs fed low crude protein diets supplemented with crystalline amino acids.

    Science.gov (United States)

    Liu, X T; Ma, W F; Zeng, X F; Xie, C Y; Thacker, P A; Htoo, J K; Qiao, S Y

    2015-10-01

    Four 28-d experiments were conducted to determine the standardized ileal digestible (SID) valine (Val) to lysine (Lys) ratio required for 26- to 46- (Exp. 1), 49- to 70- (Exp. 2), 71- to 92- (Exp. 3), and 94- to 119-kg (Exp. 4) pigs fed low CP diets supplemented with crystalline AA. The first 3 experiments utilized 150 pigs (Duroc × Landrace × Large White), while Exp. 4 utilized 90 finishing pigs. Pigs in all 4 experiments were randomly allocated to 1 of 5 diets with 6 pens per treatment (3 pens of barrows and 3 pens of gilts) and 5 pigs per pen for the first 3 experiments and 3 pigs per pen for Exp. 4. Diets for all experiments were formulated to contain SID Val to Lys ratios of 0.55, 0.60, 0.65, 0.70, or 0.75. In Exp. 1 (26 to 46 kg), ADG increased (linear, = 0.039; quadratic, = 0.042) with an increasing dietary Val:Lys ratio. The SID Val:Lys ratio to maximize ADG was 0.62 using a linear broken-line model and 0.71 using a quadratic model. In Exp. 2 (49 to 70 kg), ADG increased (linear, = 0.021; quadratic, = 0.042) as the SID Val:Lys ratio increased. G:F improved (linear, = 0.039) and serum urea nitrogen (SUN) decreased (linear, = 0.021; quadratic, = 0.024) with an increased SID Val:Lys ratio. The SID Val:Lys ratios to maximize ADG as well as to minimize SUN levels were 0.67 and 0.65, respectively, using a linear broken-line model and 0.72 and 0.71, respectively, using a quadratic model. In Exp. 3 (71 to 92 kg), ADG increased (linear, = 0.007; quadratic, = 0.022) and SUN decreased (linear, = 0.011; quadratic, = 0.034) as the dietary SID Val:Lys ratio increased. The SID Val:Lys ratios to maximize ADG as well as to minimize SUN levels were 0.67 and 0.67, respectively, using a linear broken-line model and 0.72 and 0.74, respectively, using a quadratic model. In Exp. 4 (94 to 119 kg), ADG increased (linear, = 0.041) and G:F was improved (linear, = 0.004; quadratic, = 0.005) as the dietary SID Val:Lys ratio increased. The SID Val:Lys ratio to maximize G:F was 0

  8. Application of multi-dimensional discrimination diagrams and probability calculations to Paleoproterozoic acid rocks from Brazilian cratons and provinces to infer tectonic settings

    Science.gov (United States)

    Verma, Sanjeet K.; Oliveira, Elson P.

    2013-08-01

    In present work, we applied two sets of new multi-dimensional geochemical diagrams (Verma et al., 2013) obtained from linear discriminant analysis (LDA) of natural logarithm-transformed ratios of major elements and immobile major and trace elements in acid magmas to decipher plate tectonic settings and corresponding probability estimates for Paleoproterozoic rocks from Amazonian craton, São Francisco craton, São Luís craton, and Borborema province of Brazil. The robustness of LDA minimizes the effects of petrogenetic processes and maximizes the separation among the different tectonic groups. The probability based boundaries further provide a better objective statistical method in comparison to the commonly used subjective method of determining the boundaries by eye judgment. The use of readjusted major element data to 100% on an anhydrous basis from SINCLAS computer program, also helps to minimize the effects of post-emplacement compositional changes and analytical errors on these tectonic discrimination diagrams. Fifteen case studies of acid suites highlighted the application of these diagrams and probability calculations. The first case study on Jamon and Musa granites, Carajás area (Central Amazonian Province, Amazonian craton) shows a collision setting (previously thought anorogenic). A collision setting was clearly inferred for Bom Jardim granite, Xingú area (Central Amazonian Province, Amazonian craton) The third case study on Older São Jorge, Younger São Jorge and Maloquinha granites Tapajós area (Ventuari-Tapajós Province, Amazonian craton) indicated a within-plate setting (previously transitional between volcanic arc and within-plate). We also recognized a within-plate setting for the next three case studies on Aripuanã and Teles Pires granites (SW Amazonian craton), and Pitinga area granites (Mapuera Suite, NW Amazonian craton), which were all previously suggested to have been emplaced in post-collision to within-plate settings. The seventh case

  9. THE EFFECT OF ACID ROCK FROM CĂLIMANI MOUNTAINS ON MAKING UP A NUTRITIVE SUPPORT FOR PLANTS, BASED ON RED MUD

    Directory of Open Access Journals (Sweden)

    Radu Lacatusu

    2013-12-01

    Full Text Available The paper presents the results of an experiment carried out in controlled conditions, regarding triticale plants growth on a nutritive layer consisting of a mixture of red mud, acid rock and compost, in different proportions. The analytical results highlighted the strongly alkaline reaction of the layer, high organic carbon, mobile phosphorus and potassium contents and low nitrogen contents. The layer has a high salinity and sodium salts are predominant. The total microelements and heavy metals contents are generally acceptable. The triticale plants grew in these conditions up to 10-15 cm height, when the experiment was stopped. The plants accumulated normal nitrogen, calcium and magnesium quantities, low potassium ones, high phosphorus and very high sodium contents. The metallic microelements (copper, iron, manganese, zinc accumulated at relatively normal levels, but the heavy metals (cadmium, cobalt, chromium, nickel, lead concentrated up to values several tens of times higher than the normal contents. Introducing the obtained vegetal mass in the nutritive layer will contribute to enhancing its fertility for the next vegetation cycles.

  10. Groundwater in granitic rocks

    International Nuclear Information System (INIS)

    A comparison of published chemical analyses of ground waters found in granitic rocks from a variety of locations shows that their compositions fall into two distinct classes. Ground waters from shallow wells and springs have a high bicarbonate/chloride ratio resulting from the neutralization of carbonic acid (dissolved CO2) by weathering reactions. The sodium, potassium, and silica released by weathering reactions drive the solutions away from equilibrium with the dominant minerals in the granites (i.e., quartz, muscovite, potassium feldspar, and albite). On the other hand, ground waters from deep wells and excavations are rich in chloride relative to bicarbonate. Their Na, K, H, and silica activities indicate that they are nearly equilibrated with the granite minerals suggesting a very long residence time in the host rock. These observations furnish the basis for a powerful tool to aid in selecting sites for radioactive waste disposal in granitic rocks. When water-bearing fractures are encountered in these rocks, a chemical analysis of the solutions contained within the fracture can determine whether the water came from the surface, i.e., is bicarbonate rich and not equilibrated, or whether it is some sort of connate water that has resided in the rock for a long period, i.e., chloride rich and equilibrated. This technique should allow immediate recognition of fracture systems in granitic radioactive waste repositories that would allow radionuclides to escape to the surface

  11. The Immobilization Effect of Oxalic Acid Activated Phosphate Rocks Applied to the Cd Contaminated Farmland Soil in Mining Area%草酸活化磷矿粉对矿区污染土壤中Cd的钝化效果

    Institute of Scientific and Technical Information of China (English)

    许学慧; 姜冠杰; 胡红青; 刘永红; 付庆灵; 黄丽

    2011-01-01

    通过盆栽莴苣试验,研究施加草酸活化磷矿粉对矿区农田土壤Cd污染钝化修复的效果.结果表明:施加南漳磷矿粉后,供试土壤交换态Cd的含量比对照降低了12.5%~20.3%;施加不同浓度经草酸活化过的南漳磷矿粉后,交换态Cd的含量与对照相比最高降低了39.5%.施加保康磷矿粉后,随着施加量的增加,与对照相比,交换态Cd的含量变化不显著;施加经草酸活化保康磷矿粉,土壤交换态Cd含量比对照最高降低了21.5%.同时,与对照相比,施加南漳磷矿粉后,残渣态Cd含量最大值是对照的2.03倍,施加经草酸活化的南漳磷矿粉后,残渣态Cd含量最大值是对照的2.61倍;施加保康磷矿粉和活化磷矿粉后,残渣态Cd含量与对照也有显著增加.施加磷矿粉和活化磷矿粉可以显著降低莴苣各部分对Cd的吸收,减少Cd在莴苣植株的累积.在施加两种活化磷矿粉后,与对照相比,莴苣地上部分Cd含量分别最多可降低41.4%、59.3%,根部Cd含量最多降低47.7%、55.1%.因此,低品位磷矿粉经草酸活化后施于Cd污染土壤,可以更好地钝化固定土壤中的Cd.%A pot experiment was conducted to study the Cd immobilization effect of oxalic acid activated phosphate rocks on a contaminated soil in mining area, using lettuce as a test crop. The results showed that when applied Nanzhang phosphate rock, the content of exchangeable Cd in the soil was reduced by 12.5%~20.3%. Application of oxalic acid activated Nanzhang phosphate rock at different levels, decreased the content of exchangeable Cd up to 39.5%, compared with the control treatment. The change in the content of exchangeable Cd as the amount of applied Baokang phosphate rock increased was slightly significant. The maximum reduction of 21.5% exchangeable Cd was obtained after applying Baokang activated phosphate rock to the soil. At the same time, the maximum content of residual Cd was 2.03 times higher than

  12. Experimental deformation of polyphase rock analogues

    NARCIS (Netherlands)

    Bons, P.D.

    1993-01-01

    This thesis presents an investigation into the mechanical properties of ductile polyphase materials, which were studied by a number of different techniques. The first approach was to do creep tests and transparent deformation cell experiments with two-phase composites of organic crystalline rock-ana

  13. Rock Phosphate Solubilization Mechanisms of One Fungus and One Bacterium

    Institute of Scientific and Technical Information of China (English)

    LIN Qi-mei; ZHAO Xiao-rong; ZHAO Zi-juan; LI Bao-guo

    2002-01-01

    Many microorganisms can dissolve the insoluble phosphates like apatite. However, the mechanisms are still not clear. This study was an attempt to investigate the mechanisms of rock phosphate solubilization by an Aspergillus 2TCiF2 and an Arthrobacter1TCRi7. The results indicated that the fungus produced a large amount of organic acids, mainly oxalic acid. The total quantity of the organic acids produced by the fungus was 550 times higher than that by the bacterium. Different organic acids had completely different capacities to solubilize the rock. Oxalic acid and citric acid had stronger capacity to dissolve the rock than malic acid, tartaric acid, lactic acid, acetic acid, malonic acid and succinic acid. The fungus solubilized the rock through excreting both proton and organic acids. The rock solubilization of the bacterium depended on only proton.

  14. Influence of Carbon on the Electrical Properties of Crustal Rocks

    Energy Technology Data Exchange (ETDEWEB)

    Mathez, E. A.

    2002-11-19

    The report summarizes work to determine the nature and distribution of carbon on microcracks in crystalline rocks by time-of-flight secondary ion mass spectroscopy. It also summarizes the results of a workshop devoted to investigating how carbon in rocks influences electrical conductivity and whether carbon on fracture surfaces can account for the electrical conductivity structure of the crust.

  15. Evaluation of phospherus uptake from Minjingu phosphate rock, growth and nodulation of agroforestry tree species on an acid soil from Kenya

    International Nuclear Information System (INIS)

    A series of studies were carried out to study the effect of P application on fast growing multi-purpose trees. A greenhouse experiment was conducted to evaluate availability and uptake of phosphorus (P) from Minjingu phosphate rock (MPR). An acid soil and six agroforestry tree species namely Leucena leuco-cephala, Gliricidia sepium, Sesbania sesban, Grevillea robusta, Cassia siamea and Eucalyptus grandis were used. Phosphorus was applied at 25.8 mg P/ kg soil as Minjingu phosphate rock (MPR) or Triple Superphosphate (TSP). Pregerminated seedlings were transplanted and divided into two sequential harvests at 3 and 6 MAT (months after transplanting). 32P isotope carrier free solution was added to transplanted seedlings at the beginning and when they were 3 months old. The soil was tested for isotopically exchangeable P by incubating the soil with the MPR and TSP. The soil was high in P-fixing capacity. At 3 MAT all the species except G. robusta gave a 150-250% significantly higher stem dry weights where P was added and L. leuco-cephala, S. sesban and C. siamea maintained this up to 6 MAT. The legumes and E. grandis where P was applied differed significantly from controls in root dry weight with Minjingu PR being superior with G.sepium and E. grandis. The legumes and E. grandis had significantly higher P uptake where P was applied at 3 MAT. The relative availability of MPR at 3 MAT showed that L.leucocephala and G. sepium derived 2.93 and 1.06 times more P from Minjingu PR than from TSP respectively. Data obtained from G. robusta P uptake showed that this species preferred soil P to externally supplied P in the three sampling periods. Tree species and fertilizer P interactions at 6 MAT were highly significant (P=0.01). Vesicular arbuscular mycorrhiza (VAM) inoculation improved growth, P uptake from MPR and nodulation of G. sepium seedlings. Inoculating L. leucocephala seedlings with VAM increased availability of P from MPR. (author)

  16. Non-crystalline composite tissue engineering scaffolds using boron-containing bioactive glass and poly(d,l-lactic acid) coatings

    Energy Technology Data Exchange (ETDEWEB)

    Mantsos, T; Chatzistavrou, X; Roether, J A; Boccaccini, A R [Department of Materials, Imperial College London, South Kensington Campus, London SW7 2AZ (United Kingdom); Hupa, L; Arstila, H, E-mail: a.boccaccini@imperial.ac.u [Process Chemistry Centre, Abo Akademi University, Piispankatu 8, FI-20500 Turku (Finland)

    2009-10-15

    The aim of this study was the fabrication of three-dimensional, highly porous, bioactive scaffolds using a recently developed bioactive glass powder, denominated '0106', with nominal composition (in wt%): 50 SiO{sub 2}, 22.6 CaO, 5.9 Na{sub 2}O, 4 P{sub 2}O{sub 5}, 12 K{sub 2}O, 5.3 MgO and 0.2 B{sub 2}O{sub 3}. The optimum sintering conditions for the fabrication of scaffolds by the foam-replica method were identified (sintering temperature: 670 deg, C and dwell time: 5 h). Composite samples were also fabricated by applying a biopolymer coating of poly({sub D,L}-lactic acid) (PDLLA) using a dip coating process. The average compressive strength values were 0.4 MPa for uncoated and 0.6 MPa for coated scaffolds. In vitro bioactivity studies in simulated body fluid (SBF) showed that a carbonate hydroxyapatite (HCAp) layer was deposited on uncoated and coated scaffolds after only 4 days of immersion in SBF, demonstrating the high in vitro bioactivity of the scaffolds. It was also confirmed that the scaffold structure remained amorphous (no crystallization) after the specific heat treatment used, with scaffolds exhibiting mechanical properties and bioactivity suitable for use in bone tissue engineering applications.

  17. Non-crystalline composite tissue engineering scaffolds using boron-containing bioactive glass and poly(D,L-lactic acid) coatings.

    Science.gov (United States)

    Mantsos, T; Chatzistavrou, X; Roether, J A; Hupa, L; Arstila, H; Boccaccini, A R

    2009-10-01

    The aim of this study was the fabrication of three-dimensional, highly porous, bioactive scaffolds using a recently developed bioactive glass powder, denominated '0106', with nominal composition (in wt%): 50 SiO(2), 22.6 CaO, 5.9 Na(2)O, 4 P(2)O(5), 12 K(2)O, 5.3 MgO and 0.2 B(2)O(3). The optimum sintering conditions for the fabrication of scaffolds by the foam-replica method were identified (sintering temperature: 670 degrees C and dwell time: 5 h). Composite samples were also fabricated by applying a biopolymer coating of poly((D,L)-lactic acid) (PDLLA) using a dip coating process. The average compressive strength values were 0.4 MPa for uncoated and 0.6 MPa for coated scaffolds. In vitro bioactivity studies in simulated body fluid (SBF) showed that a carbonate hydroxyapatite (HCAp) layer was deposited on uncoated and coated scaffolds after only 4 days of immersion in SBF, demonstrating the high in vitro bioactivity of the scaffolds. It was also confirmed that the scaffold structure remained amorphous (no crystallization) after the specific heat treatment used, with scaffolds exhibiting mechanical properties and bioactivity suitable for use in bone tissue engineering applications. PMID:19776493

  18. Non-crystalline composite tissue engineering scaffolds using boron-containing bioactive glass and poly(d,l-lactic acid) coatings

    International Nuclear Information System (INIS)

    The aim of this study was the fabrication of three-dimensional, highly porous, bioactive scaffolds using a recently developed bioactive glass powder, denominated '0106', with nominal composition (in wt%): 50 SiO2, 22.6 CaO, 5.9 Na2O, 4 P2O5, 12 K2O, 5.3 MgO and 0.2 B2O3. The optimum sintering conditions for the fabrication of scaffolds by the foam-replica method were identified (sintering temperature: 670 deg, C and dwell time: 5 h). Composite samples were also fabricated by applying a biopolymer coating of poly(D,L-lactic acid) (PDLLA) using a dip coating process. The average compressive strength values were 0.4 MPa for uncoated and 0.6 MPa for coated scaffolds. In vitro bioactivity studies in simulated body fluid (SBF) showed that a carbonate hydroxyapatite (HCAp) layer was deposited on uncoated and coated scaffolds after only 4 days of immersion in SBF, demonstrating the high in vitro bioactivity of the scaffolds. It was also confirmed that the scaffold structure remained amorphous (no crystallization) after the specific heat treatment used, with scaffolds exhibiting mechanical properties and bioactivity suitable for use in bone tissue engineering applications.

  19. 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…

  20. 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

  1. Exploring deep potential aquifer in water scarce crystalline rocks

    Indian Academy of Sciences (India)

    Subash Chandra; E Nagaiah; D V Reddy; V Ananda Rao; Shakeel Ahmed

    2012-12-01

    Characterization of the shear zone with pole–pole electrical resistivity tomography (ERT) was carried out to explore deep groundwater potential zone in a water scarce granitic area. As existing field conditions does not always allow to plant the remote electrodes at sufficiently far of distance, the effect of insufficient distance of remote electrodes on apparent resistivity measurement was studied and shown that the transverse pole–pole array affects less compared to the collinear pole–pole array. Correction factor have been computed for transverse pole–pole array for various positions of the remote electrodes. The above results helped in exploring deep aquifer site, where a 270 m deep well was drilled. Temporal hydro-chemical samples collected during the pumping indicated the hydraulic connectivity between the demarcated groundwater potential fractures. Incorporating all the information derived from different investigations, a subsurface model was synthetically simulated and generated 2D electrical resistivity response for different arrays and compared with the field responses to further validate the geoelectrical response of deep aquifer set-up associated with lineament.

  2. Effects of citrate and NaCl on size, morphology, crystallinity and microstructure of calcium phosphates obtained from aqueous solutions at acidic or near-neutral pH.

    Science.gov (United States)

    Mekmene, Omar; Rouillon, Thierry; Quillard, Sophie; Pilet, Paul; Bouler, Jean-Michel; Pezennec, Stéphane; Gaucheron, Frédéric

    2012-05-01

    Precipitation of calcium phosphates occurs in dairy products and depending on pH and ionic environment, several salts with different crystallinity can form. The present study aimed to investigate the effects of NaCl and citrate on the characteristics of precipitates obtained from model solutions of calcium phosphate at pH 6·70 maintained constant or left to drift. The ion speciation calculations showed that all the starting solutions were supersaturated with respect to dicalcium phosphate dihydrate (DCPD), octacalcium phosphate (OCP) and hydroxyapatite (HAP) in the order HAP>OCP>DCPD. X-ray diffraction (XRD) and Fourier transform infrared (FTIR) analyses of the precipitates showed that DCPD was formed at drifting pH (acidic final pH) whereas poor crystallised calcium deficient apatite was mainly formed at constant pH (6·70). Laser light scattering measurements and electron microscopy observations showed that citrate had a pronounced inhibitory effect on the crystallisation of calcium phosphates both at drifting and constant pH. This resulted in the decrease of the particle sizes and the modification of the morphology and the microstructure of the precipitates. The inhibitory effect of citrate mainly acted by the adsorption of the citrate molecules onto the surfaces of newly formed nuclei of calcium phosphate, thereby changing the morphology of the growing particles. These findings are relevant for the understanding of calcium phosphate precipitation from dairy byproducts that contain large amounts of NaCl and citrate. PMID:22559064

  3. Thermodynamics of Crystalline States

    CERN Document Server

    Fujimoto, Minoru

    2013-01-01

    Thermodynamics is a well-established discipline of physics for properties of matter in thermal equilibrium with the surroundings. Applying to crystals, however, the laws encounter undefined properties of crystal lattice, which therefore need to be determined for a clear and well-defined description of crystalline states. Thermodynamics of Crystalline States explores the roles played by order variables and dynamic lattices in crystals in a wholly new way. The book begins by clarifying basic concepts for stable crystals. Next, binary phase transitions are discussed to study collective motion of order variables, as described mostly as classical phenomena. New to this edition is the examination of magnetic crystals, where magnetic symmetry is essential for magnetic phase transitions. The multi-electron system is also discussed  theoretically, as a quantum-mechanical example, for superconductivity in metallic crystals. Throughout the book, the role played by the lattice is emphasized and studied in-depth. Thermod...

  4. A Rock Mechanics and Coupled Hydro mechanical Analysis of Geological Repository of High Level Nuclear Waste in Fractured Rocks

    International Nuclear Information System (INIS)

    This paper introduces a few case studies on fractured hard rock based on geological data from Sweden, Korea is one of a few countries where crystalline rock is the most promising rock formation as a candidate site of geological repository of high level nuclear waste. Despite the progress made in the area of rock mechanics and coupled hydro mechanics, extensive site specific study on multiple candidate sites is essential in order to choose the optimal site. For many countries concerned about the safe isolation of nuclear wastes from the biosphere, disposal in a deep geological formation is considered an attractive option. In geological repository, thermal loading continuously disturbs the repository system in addition to disturbances a recent development in rock mechanics and coupled hydro mechanical study using DFN(Discrete Fracture Network) - DEM(Discrete Element Method) approach mainly applied in hard, crystalline rock containing numerous fracture which are main sources of deformation and groundwater flow

  5. Colliding Crystalline Beams

    International Nuclear Information System (INIS)

    The understanding of crystalline beams has advanced to the point where one can now, with reasonable confidence, undertake an analysis of the luminosity of colliding crystalline beams. Such a study is reported here. It is necessary to observe the criteria, previously stated, for the creation and stability of crystalline beams. This requires, firstly, the proper design of a lattice. Secondly, a crystal must be formed, and this can usually be done at various densities. Thirdly, the crystals in a colliding-beam machine are brought into collision. We study all of these processes using the molecular dynamics (MD) method. The work parallels what was done previously, but the new part is to study the crystal-crystal interaction in collision. We initially study the zero-temperature situation. If the beam-beam force (or equivalent tune shift) is too large then over-lapping crystals can not be created (rather two spatially separated crystals are formed). However, if the beam-beam force is less than but comparable to that of the space-charge forces between the particles, we find that overlapping crystals can be formed and the beam-beam tune shift can be of the order of unity. Operating at low but non-zero temperature can increase the luminosity by several orders of magnitude over that of a usual collider. The construction of an appropriate lattice, and the development of adequately strong coding, although theoretically achievable, is a challenge in practice

  6. Quantifying glassy and crystalline basalt partitioning in the oceanic crust

    Science.gov (United States)

    Moore, Rachael; Ménez, Bénédicte

    2016-04-01

    The upper layers of the oceanic crust are predominately basaltic rock, some of which hosts microbial life. Current studies of microbial life within the ocean crust mainly focus on the sedimentary rock fraction, or those organisms found within glassy basalts while the potential habitability of crystalline basalts are poorly explored. Recently, there has been recognition that microbial life develops within fractures and grain boundaries of crystalline basalts, therefore estimations of total biomass within the oceanic crust may be largely under evaluated. A deeper understanding of the bulk composition and fractionation of rocks within the oceanic crust is required before more accurate estimations of biomass can be made. To augment our understanding of glassy and crystalline basalts within the oceanic crust we created two end-member models describing basalt fractionation: a pillow basalt with massive, or sheet, flows crust and a pillow basalt with sheeted dike crust. Using known measurements of massive flow thickness, dike thickness, chilled margin thickness, pillow lava size, and pillow lava glass thickness, we have calculated the percentage of glassy versus crystalline basalts within the oceanic crust for each model. These models aid our understanding of textural fractionation within the oceanic crust, and can be applied with bioenergetics models to better constrain deep biomass estimates.

  7. Measurement of surface crystallinity of PAA and PAANa coatings and its effect on hydrophilicity of coatings

    Institute of Scientific and Technical Information of China (English)

    潘春跃; 刘清泉; 徐先华; 陈振华

    2003-01-01

    The solutions of poly(acrylic acid)(PAA), poly(acrylic acid sodium)(PAANa) were coated on aluminium fins by roll coating method. The coatings with different crystallinity were obtained by varying baking time and temperature. Their surface crystallinity and surface tension were measured, and their spreading speed constant and equilibrium contact angle were tested also. The correlation of surface crystallinity, surface tension, spreading speed constant and surface hydrophilicity was discussed. It is demonstrated that surface tension and spreading speed constant increase, while equilibrium contact angle declines with increasing surface crystallinity of coatings, that is to say, the hydrophilicity of coatings is improved with surface crystallinity of coatings increasing.

  8. Back-thrusting in Lesser Himalaya: Evidences from magnetic fabric studies in parts of Almora crystalline zone, Kumaun Lesser Himalaya

    Indian Academy of Sciences (India)

    Amar Agarwal; K K K K Agarwal; R Bali; Chandra Prakash; Gaurav Joshi

    2016-06-01

    The present study aims to understand evolution of the Lesser Himalaya, which consists of (meta) sedimentaryand crystalline rocks. Field studies, microscopic and rock magnetic investigations have beencarried out on the rocks near the South Almora Thrust (SAT) and the North Almora Thrust (NAT),which separates the Almora Crystalline Zone (ACZ) from the Lesser Himalayan sequences (LHS). Theresults show that along the South Almora Thrust, the deformation is persistent; however, near theNAT deformation pattern is complex and implies overprinting of original shear sense by a youngerdeformational event. We attribute this overprinting to late stage back-thrusting along NAT, active afterthe emplacement of ACZ. During this late stage back-thrusting, rocks of the ACZ and LHS were coupled.Back-thrusts originated below the Lesser Himalayan rocks, probably from the Main Boundary Thrust,and propagated across the sedimentary and crystalline rocks. This study provides new results frommultiple investigations, and enhances our understanding of the evolution of the ACZ.

  9. Analysis of organic acid salts of marine carbonate rocks in Tarim Basin%塔里木盆地海相碳酸盐岩中有机酸盐的分析

    Institute of Scientific and Technical Information of China (English)

    孙敏卓; 孟仟祥; 郑建京; 王国仓; 房嬛; 王作栋

    2013-01-01

    提出热重/差热(TG/DTA)、红外光谱(IR)和气相色谱/质谱联用结合(GC/MS)分析塔里木盆地海相碳酸盐岩中有机酸盐的方法.用TG/DTA对标样(硬脂酸、硬脂酸镁、硬脂酸钙和碳酸钙)进行分析,确定有机酸气化而有机酸盐不气化的温度区间,由此设计从碳酸盐岩中分离和提取有机酸盐的实验步骤.研究结果表明:验证碳酸盐岩中确实存在有机酸盐;塔里木盆地海相碳酸盐岩中有机酸盐的含量与样品中的碳酸盐含量无相关性,而与样品的沉积相类型具有一定的相关性,即斜坡相沉积环境的沉积岩中相对富集有机酸盐.%A method was developed for the determination of the organic acid salts of marine carbonate rocks in Tarim Basin by the thermogravimetric/differential thermal (TG/DTA), infrared spectroscopy (IR) and gas chromatography/mass spectrometry (GC/MS).By analyzing the guide sample such as the stearic acid, the magnesium stearate, the calcium stearate and the calcium carbonate by TG/DTA, the temperature range where the organic acid was gasificated while the organic acid salt wasn't gasificated were defined, and thereby the experimental procedures for separating and extracting the organic acid salt from the carbonatite rock was designed.The results show that the organic acid salt exists in carbonatite rock by using the infrared spectroscopy and gas chromatography/mass spectrometry. The quantity of the organic acid salts of marine carbonate rocks in Tarim Basin is insignificantly correlated with the carbonate content of samples, but it is correlated with the types of sedimentary facies of samples, namely relative enrichment of the organic acid salts in sedimentary strata of the slope facies sedimentary environment.

  10. Ore-forming fluid constraints on illite crystallinity (IC) at Dexing porphyry copper deposit, Jiangxi Province

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Illite, a distinctive kind of clay minerals of potassiumalteration within the hydrothermal alteration zone, frequently occurs at the Tongchang porphyry copper deposit ore field. The illite crystallinity (IC) value and expandability are mainly affected by water/rock ratio or fluid flux. It was formed by illitization of plagioclase and micas during hydrothermal fluid-rock interaction within the porphyry body and near the contact zone with wall rocks. Moreover, the negative correlation between illite index (IC) and copper grade indicates that within the alteration zone, the smaller the illite crystallinity value, the higher the alteration degree, and the higher the copper grade due to higher water/rock ratio. At lower levels of the porphyry body, however, the illite crystallinity (IC) values are mainly controlled by temperature and time duration.

  11. Geology and Geochemistry of Reworking Gold Deposits in Intrusive Rocks of China—Ⅰ. Features of the Intrusive Rocks

    Institute of Scientific and Technical Information of China (English)

    王秀璋; 程景平; 等

    1998-01-01

    Most gold deposits in intrusive rocks were formed as a result of reworking processes.the intrusive rocks containing gold deposits and consisting of ultramafic-mafic,intermediateacid and alkaline rocks of the Archean,Proterozoic,Caledonian,Hercynian and Yenshanian periods occur in cratons,activated zones of cratons and fold belts.Among them,ultramaficmafic rocks,diorite,alkaline rocks,and anorthosite are products of remelting in the mantle or mantle-crust or mantle with crustal contamination,However,auriferous intermediate-acid rocks are products of metasomatic-remelting in auriferous volcainc rocks or auriferous volcanosedimentary rocks in the deep crust.

  12. Crystalline mesoporous metal oxide

    Institute of Scientific and Technical Information of China (English)

    Wenbo Yue; Wuzong Zhou

    2008-01-01

    Since the discovery of many types of mesoporous silicas, such as SBA-15, KIT-6, FDU-12 and SBA-16, porous crystalline transition metal oxides, such as Cr2O3, Co3O4, In2O3, NiO, CeO2, WO3, Fe2O3 and MnO2, have been synthesized using the mesoporous silicas as hard templates. Several synthetic methods have been developed. These new porous materials have high potential applications in catalysis, Li-ion rechargeable batteries and gas sensors. This article gives a brief review of the research of porous crystals of metal oxides in the last four years.

  13. The variation in composition of ultramafic rocks and the effect on their suitability for carbon dioxide sequestration by mineralisation following acid leaching

    OpenAIRE

    Styles, M. T.; Sanna, A.; Lacinska, A.M.; Naden, J.; Maroto-Valer, M.

    2014-01-01

    Carbon dioxide capture and storage by mineralization has been proposed as a possible technology to contribute to the reduction of global CO2 levels. A main candidate as a feed material, to supply Mg cations for combination with CO2 to form carbonate, is the family of ultramafi c rocks, Mgrich silicate rocks with a range of naturally occurring mineralogical compositions. A classifi cation scheme is described and a diagram is proposed to display the full range of both fresh and alte...

  14. Rock stresses (Grimsel rock laboratory)

    International Nuclear Information System (INIS)

    On the research and development project 'Rock Stress Measurements' the BGR has developed and tested several test devices and methods at GTS for use in boreholes at a depth of 200 m and has carried out rock mechanical and engineering geological investigations for the evaluation and interpretation of the stress measurements. The first time a computer for data processing was installed in the borehole together with the BGR-probe. Laboratory tests on hollow cylinders were made to study the stress-deformation behavior. To validate and to interprete the measurement results some test methods were modelled using the finite-element method. The dilatometer-tests yielded high values of Young's modulus, whereas laboratory tests showed lower values with a distinct deformation anisotropy. Stress measurements with the BGR-probe yielded horizontal stresses being higher than the theoretical overburden pressure and vertical stresses which agree well with the theoretical overburden pressure. These results are comparable to the results of the hydraulic fracturing tests, whereas stresses obtained with CSIR-triaxial cells are generally lower. The detailed geological mapping of the borehole indicated relationships between stress and geology. With regard to borehole depth different zones of rock structure joint frequency, joint orientation, and orientation of microfissures as well as stress magnitude, stress direction, and degree of deformation anisotropy could be distinguished. (orig./HP)

  15. Elastic properties of granulite facies rocks of Mahabalipuram, Tamil Nadu, India

    Indian Academy of Sciences (India)

    M V M S Rao; K J Prasanna Lakshmi; L P Sarma; K B Chary

    2006-12-01

    Compressional and shear wave velocities and attenuation measurements have been carried out in some of the borehole samples of acidic, basic and intermediate granulites of Mahabalipuram, Tamil Nadu, India. The results have been obtained at ambient conditions using ‘time-of-flight’ pulse transmission technique at 1.0MHz frequency. The results show linear relationships between velocity and density, and velocity and attenuation properties of the rocks. The acidic granulites show lower velocities and higher attenuation than the intermediate and basic granulites. The average values of the Poisson’s ratio of acidic, intermediate and basic granulites have been found to be 0.210, 0.241 and 0.279 respectively. The variations in velocities and attenuation in these low porosity crystalline rocks are found to be strongly influenced by their mineral composition. The laboratory velocity data (extrapolated to high pressure) of the present study and the published field velocity data from deep seismic sounding studies indicate that these granulite facies rocks may belong to mid-crustal depths only.

  16. X-ray studies of crystalline complexes involving amino acids and peptides. XLIV. Invariant features of supramolecular association and chiral effects in the complexes of arginine and lysine with tartaric acid.

    Science.gov (United States)

    Selvaraj, M; Thamotharan, S; Roy, Siddhartha; Vijayan, M

    2007-06-01

    The tartaric acid complexes with arginine and lysine exhibit two stoichiometries depending upon the ionization state of the anion. The structures reported here are DL-argininium DL-hydrogen tartrate, bis(L-argininium) L-tartrate, bis(DL-lysinium) DL-tartrate monohydrate, L-lysinium D-hydrogen tartrate and L-lysinium L-hydrogen tartrate. During crystallization, L-lysine preferentially interacts with D-tartaric acid to form a complex when DL-tartaric acid is used in the experiment. The anions and the cations aggregate into separate alternating layers in four of the five complexes. In bis(L-argininium) L-tartrate, the amino acid layers are interconnected by individual tartrate ions which do not interact among themselves. The aggregation of argininium ions in the DL- and the L-arginine complexes is remarkably similar, which is in turn similar to those observed in other dicarboxylic acid complexes of arginine. Thus, argininium ions have a tendency to assume similar patterns of aggregation, which are largely unaffected by a change in the chemistry of partner molecules such as the introduction of hydroxyl groups or a change in chirality or stoichiometry. On the contrary, the lysinium ions exhibit fundamentally different aggregation patterns in the DL-DL complexes on the one hand and L-D and L-L complexes on the other. Interestingly, the pattern in the L-D complex is similar to that in the L-L complex. The lysinium ions in the DL-DL complex exhibit an aggregation pattern similar to those observed in the DL-lysine complexes involving other dicarboxylic acids. Thus, the effect of change in the chirality of a subset of the component complexes could be profound or marginal, in an unpredictable manner. The relevant crystal structures appear to indicate that the preference of L-lysine for D-tartaric acid is perhaps caused by chiral discrimination resulting from the amplification of a small energy difference.

  17. Comparison of greenhouse and 32P isotopic laboratory methods for evaluating the agronomic effectiveness of natural and modified rock phosphates in some acid soils of Ghana

    International Nuclear Information System (INIS)

    Phosphorus deficiency is one of the major constraints for normal plant growth and crop yields in the acid soils of Ghana and therefore addition of P inputs is required for sustainable crop production. This is often difficult, if not impossible for small-scale farmers due to the high cost of mineral P fertilizers and limited access to fertilizer supplies. Direct application of finely ground phosphate rocks (PRs) and their modified forms have been recommended as alternatives for P fertilization. The direct application of the natural and modified PRs to these acid soils implies the need to predict their agronomic effectiveness of the PRs in the simplest and most cost-effective manner. In this study the classical greenhouse pot experiment was compared to the 32P isotopic kinetics laboratory method for evaluating the agronomic effectiveness of natural and modified Togo PR in six highly weathered Oxisols from southwest Ghana. In the 32P isotopic kinetics laboratory experiment the six soil samples were each fertilised at the rate of 50 mg P kg-1 soil in the form of triple superphosphate (TSP), Togo PAPR-50%, and Togo PR, respectively. Controls without P amendment were also included. Isotopic exchange kinetics experiments were carried out on two sets of samples, immediately after P fertilizer additions (without incubation) and after 6 weeks of incubation under wet conditions and at a room temperature of 25 deg C. In the greenhouse pot experiment, P fertilizers in the form of Togo PR, Togo PAPR, Mali PR and TSP were each applied to the six soils at rates equivalent to 0, 30, 60, and 120 kg P ha-1, respectively. The P fertilizers were mixed with the soils and maize (Zea mays L.) variety Obatanpa was grown for 42 days before harvest. The isotopic kinetics data of the control samples indicated that 5 of the studied soils had very low P fertility status as reflected by their low P concentrations in solution (CP-1) and low exchangeable P (E1min -1). The capacity factor and the

  18. 溶血磷脂酸调控RhoA/ROCK2信号通路对乳腺癌细胞增殖的影响%Influence of lysophosphatidic acid on proliferation of breast cancer cell by adjusted RhoA/ROCK2 signal pathway

    Institute of Scientific and Technical Information of China (English)

    许海; 段刚峰

    2013-01-01

    目的 探讨溶血磷脂酸(LPA)与RhoA/ROCK2信号通路对乳腺癌细胞增殖的影响及其作用机制.方法 以不同浓度LPA干预乳腺癌MDA-MB-231细胞,每隔24 h以细胞计数法观察和记录细胞的增殖.以最佳LPA促增殖浓度作用于MDA-MB-231细胞,观察Rho激酶抑制剂(Y-27632)对癌细胞的影响;以Pull-down及Western blot法检测各组细胞内RhoA活性及RhoA、ROCK2蛋白表达.结果 LPA以时间及剂量依赖性关系显著促进MDA-MB-231细胞的增殖(P<0.05);Y-27632可以显著抑制LPA的促增殖作用;LPA干预后RhoA活性及RhoA、ROCK2蛋白表达显著升高(P<0.05),Y-27632干预后RhoA活性及RhoA、ROCK2蛋白表达显著下降(P<0.05).结论 LPA可能通过调控RhoA/ROCK2信号通路促进乳腺癌细胞的增殖,为乳腺癌的临床治疗提供了新思路.%Objective To investigate the influence and mechanism of lysophosphatidic acid and RhoA/ROCK2 signal pathway on proliferation of breast cancer cell. Methods After treatment with different concentration of LPA, the proliferation of breast cancer cell MDA-MB-231 was observed and recorded by cell count method every of 24 h. MDA-MB-231 treated with optimal concentration of LPA and observed the effect of Rho kinase inhibitor( Y-27632) on LPA-induced proliferation. The activity of RhoA was tested by a pull-down way. The protein expression of RhoA and ROCK2 were determined by Western blot. Results LPA could promote MDA-MB-231 proliferation in a time and dose-dependent manner (P 〈 0. 05). ROCK inhibitor significantly inhibited LPA-induced cell proliferation (P 〈 0. 05 ). The activity of RhoA and expressionof RhoA, ROCK2 were enhanced significantly after LPA intervention (P 〈0. 05). However Y-27632 markedly decreased LPA-induced the increase of RhoA activity and protein expression of RhoA and ROCK2 ( P 〈 0. 05). Conclusions LPA may promote breast cancer cell proliferation through regulating RhoA/ROCK2 signal pathway. It provides a new idea

  19. 烃源岩生成有机酸过程的高分辨质谱研究%Characterizing thermal evolution of acid species in hydrocarbon source rock by using negative-ion ESI FT-ICR MS

    Institute of Scientific and Technical Information of China (English)

    蒋启贵; 刘鹏; 黎茂稳; 陶国亮

    2014-01-01

    研究石油中有机酸的生成过程对研究储层改造、石油润湿性及页岩油可动性评价具有重要意义。在热压生烃模拟实验基础上,对Ⅲ型烃源岩不同演化阶段生成油中的非烃馏分进行了负离子电喷雾傅立叶变换离子回旋共振质谱分析,研究了烃源岩生成有机酸过程。对样品生成有机酸分析表明,在整个演化过程烃源岩都能生成有机酸,在低演化阶段主要生成脂肪酸,随演化程度的升高,脂肪酸丰度快速减少,芳环酸开始大量生成。随演化程度的增加,芳环上短链取代基发生断裂,并促进了有机酸的缩合,使得生成的有机酸缩合度逐渐提高,高碳数有机酸逐渐减少;烃源岩生成脂肪酸系列中存在偶奇优势,生成的C16、C18脂肪酸存在异常高丰度, C16、C18脂肪酸异常丰度现象可能是污染造成的,是否与烃源岩类型及成熟度有关尚需进一步研究。%The study on the generation process of organic acid species in hydrocarbon source rocks is of a great significance for understanding reservoir alteration, oil wettability, and shale oil removability evaluation. Based on the thermocompression simulation experiment of hydrocarbon generation, the polar species of the expelled oils from a source rock (Type Ⅲ kerogen) at different maturity stages were determined by negative-ion electrospray ionization (ESI) Fourier Transform Ion Cyclotron Mass Spectrometry (ESI FT-ICR MS). The result shows that the organic acid species can be generated during the whole thermal evolution of hydrocarbon source rock. At low maturity levels (early oil window), fatty acids (DBE=1) are the most abundant species. With the increasing maturity, naphthenic acids and aromatic acids become dominant species. At higher maturity levels, most of the acidic species have been thermally cracked and aromatized, thus only the O2 class with short chains and high DBE values (aromatic acids

  20. Resources of Kaolinite Rocks in China Coal Measures

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The proved reserve of kaolinite rocks in China coal measures is about 1. 673 billion tons. The types of kaolinite rocks contain tonstein, flintclay and soft kaolin. Their origin modes include alteration of volcanic ash, terrigenous clay deposit and weathering of coal and adjacent rocks. The organic matter and organic acid play an important role in the formation of kaolinite rocks of coal measures. The difference in properties between kaolinite rock and traditional kaolin requires different processing technologies.

  1. Liquid crystalline order in polymers

    CERN Document Server

    Blumstein, Alexandre

    1978-01-01

    Liquid Crystalline Order in Polymers examines the topic of liquid crystalline order in systems containing rigid synthetic macromolecular chains. Each chapter of the book provides a review of one important area of the field. Chapter 1 discusses scattering in polymer systems with liquid crystalline order. It also introduces the field of liquid crystals. Chapter 2 treats the origin of liquid crystalline order in macromolecules by describing the in-depth study of conformation of such macromolecules in their unassociated state. The chapters that follow describe successively the liquid crystalli

  2. Liquid Crystalline Microemulsions

    Science.gov (United States)

    Huang, Chien-Yueh; Petschek, Rolfe G.

    2000-03-01

    If an isotropic component of an emulsion is replaced by one having liquid crystalline (e.g. nematic) order the equilibrium behavior can change dramatically. There are long range enthalpic effects which can result in either repulsive or attractive interactions between the surfaces of an emulsion and entropic effects which generally result in an attractive interaction between these surfaces. We review briefly the possibility of stable blue-phase like microemulsions in mixtures of chiral nematics, appropriate surfactants and an incompatible isotropic solvent. We discuss the entropic effects in a lamellar phase, including the effects of changes in elastic constants and surface-nematic coupling. The effects of fluctuations on blue phases will be briefly discussed.

  3. Terahertz Spectroscopy of Crystalline and Non-Crystalline Solids

    DEFF Research Database (Denmark)

    Parrott, Edward P. J.; Fischer, Bernd M.; Gladden, Lynn F.;

    2013-01-01

    Terahertz spectroscopy of crystalline and non-crystalline solids is probably one of the most active research fields within the terahertz community. Many potential applications, amongst which spectral recognition is probably one of the most prominent, have significantly stimulated the development...

  4. Recovery of crystallinity in ground calcite

    Energy Technology Data Exchange (ETDEWEB)

    Gammage, R.B.; Glasson, D.R.

    1976-01-01

    Recovery processes by thermal treatment and recrystallization are examined in a calcite specimen severely disordered by ball milling. As the annealing temperature is increased, restructuring in the bulk lags behind the recovery of crystalline perfection in the surface regions. Surface reordering is significant at temperatures as low as 150 to 175/sup 0/C and is rapidly completed at 400/sup 0/C. Annealing at 600/sup 0/C is required for removal of all lattice strain. Before loss of surface can occur by sintering, the temperature needs to exceed 300/sup 0/C. The corresponding temperature for a high-area precipitated calcite is 400/sup 0/C. Recovery of crystallinity is also promoted by light-etching with aqueous acid when extensive whisker growth occurs. Aging over a period of twelve years has led to loss of the ultrareactive characteristics.

  5. APPLICATIONS OF BOREHOLE-ACOUSTIC METHODS IN ROCK MECHANICS.

    Science.gov (United States)

    Paillet, Frederick L.

    1985-01-01

    Acoustic-logging methods using a considerable range of wavelengths and frequencies have proven very useful in the in situ characterization of deeply buried crystalline rocks. Seismic velocities are useful in investigating the moduli of unfractured rock, and in producing a continuous record of rock quality for comparison with discontinuous intervals of core. The considerable range of frequencies makes the investigation of scale effects possible in both fractured and unfractured rock. Several specific methods for the characterization of in situ permeability have been developed and verified in the field.

  6. Novel polypyrrole films with excellent crystallinity and good thermal stability

    Energy Technology Data Exchange (ETDEWEB)

    Jeeju, Pullarkat P., E-mail: jeejupp@gmail.com [Division for Research in Advanced Materials, Department of Physics, Cochin University of Science and Technology, Cochin-22, Kerala (India); Varma, Sreekanth J.; Francis Xavier, Puthampadath A.; Sajimol, Augustine M. [Division for Research in Advanced Materials, Department of Physics, Cochin University of Science and Technology, Cochin-22, Kerala (India); Jayalekshmi, Sankaran, E-mail: jayalekshmi@cusat.ac.in [Division for Research in Advanced Materials, Department of Physics, Cochin University of Science and Technology, Cochin-22, Kerala (India)

    2012-06-15

    Polypyrrole has drawn a lot of interest due to its high thermal and environmental stability in addition to high electrical conductivity. The present work highlights the enhanced crystallinity of polypyrrole films prepared from the redoped sample solution. Initially hydrochloric acid doped polypyrrole was prepared by chemical oxidative polymerization of pyrrole using ammonium peroxidisulphate as oxidant. The doped polypyrrole was dedoped using ammonia solution and then redoped with camphor sulphonic acid. Films were coated on ultrasonically cleaned glass substrates from the redoped sample solution in meta-cresol. The enhanced crystallinity of the polypyrrole films has been established from X-ray diffraction (XRD) studies. The room temperature electrical conductivity of the redoped polypyrrole film is about 30 times higher than that of the hydrochloric acid doped pellet sample. The results of Raman spectroscopy, Differential scanning calorimetry (DSC) and Thermogravimetric analysis (TGA) of the samples support the enhancement in crystallinity. Percentage crystallinity of the samples is estimated from XRD and DSC data. The present work is significant, since crystallinity of films is an important parameter for selecting polymers for specific applications. - Highlights: Black-Right-Pointing-Pointer Polypyrrole films redoped with CSA have been prepared from meta-cresol solution. Black-Right-Pointing-Pointer The solution casted films exhibit semi-crystallinity and good thermal stability. Black-Right-Pointing-Pointer Percentage crystallinity estimated using XRD and DSC analysis is about 65%. Black-Right-Pointing-Pointer Raman studies support the enhancement in crystallinity based on XRD and DSC data. Black-Right-Pointing-Pointer The conductivity of the film is 30 times higher than that of HCl doped sample.

  7. Uranium endowments in phosphate rock

    International Nuclear Information System (INIS)

    This study seeks to identify and specify the components that make up the prospects of U recovery from phosphate rock. A systems approach is taken. The assessment includes i) reviewing past recovery experience and lessons learned; ii) identifying factors that determine recovery; and iii) establishing a contemporary evaluation of U endowments in phosphate rock reserves, as well as the available and recoverable amounts from phosphate rock and phosphoric acid production. We find that in the past, recovery did not fulfill its potential and that the breakup of the Soviet Union worsened then-favorable recovery market conditions in the 1990s. We find that an estimated 5.7 million tU may be recoverable from phosphate rock reserves. In 2010, the recoverable tU from phosphate rock and phosphoric acid production may have been 15,000 tU and 11,000 tU, respectively. This could have filled the world U supply-demand gap for nuclear energy production. The results suggest that the U.S., Morocco, Tunisia, and Russia would be particularly well-suited to recover U, taking infrastructural considerations into account. We demonstrate future research needs, as well as sustainability orientations. We conclude that in order to promote investment and production, it seems necessary to establish long-term contracts at guaranteed prices, ensuring profitability for phosphoric acid producers. - Highlights: • We identify components that underlie the recovery of uranium from phosphate rock. • We estimate that 11,000 tU may have been recoverable from phosphoric acid in 2010. • Recovery is a resource conservation and environmental pollution control strategy. • To ensure investment in recovery technology, profitability needs to be secured

  8. Lithologic identification method and application of acidic volcanic rocks%酸性火山岩岩性识别方法及应用

    Institute of Scientific and Technical Information of China (English)

    葛红旗

    2015-01-01

    In Zhongguai area, lithology of volcanic rocks is complex and changes rapidly in vertical horizontal direction. Volcanic rocks interbed with pyroclastic rocks and form alteration. Log response characteristic has a great difference from normal volcanic rocks; however it is similar to pyroclastic rocks. Due to the extremely difficult lithology identification, aiming at common and per⁃sonality features, it needs to research corresponding volcanic rock logging recognition method. Firstly, micro resistivity was used to scan different image texture types of full bore microscan imager(FMI), which could preferably reflect rock texture and structure. Combined with FMI and core data, different FMI image patterns of volcanic rock were summarized, and rock types were identified. The rock types are volcanic breccia, dacite, tuff, andesibasalt and ganite, among them, volcanic breccia and andesibasalt are the main types. Secondly, logging parameters of conventional logging to lithological response sensitive marked by FMI were analyzed, and cross plot lithology identification method were established. Finally, compared with recognition results and thin slices, the coin⁃cidence rate reached 88 %, thereby, the interpretation accuracy of logging lithology was greatly improved.%中拐地区火山岩岩性复杂多样、纵横向变化快,火山岩与火山碎屑岩互层,且发生蚀变,测井响应特征与正常火山岩差别较大,与火山岩碎屑岩特征相似,岩性识别极其困难,需要针对共性及个性特征研究相应的火山岩测井识别方法。首先利用微电阻率扫描成像测井(FMI)上不同的图像纹理类型能较好反映岩石结构、构造特点,将FMI与岩心资料相结合,分析总结不同火山岩FMI图像模式,识别出岩石类型有火山角砾岩、英安岩、凝灰岩、玄武安山岩及花岗岩等,以火山角砾岩、玄武安山岩为主。然后分析出常规测井对FMI标定的岩性响应敏

  9. Comparison of greenhouse and {sup 32}P isotopic laboratory methods for evaluating the agronomic effectiveness of natural and modified rock phosphates in some acid soils of Ghana

    Energy Technology Data Exchange (ETDEWEB)

    Owusu-Bennoah, E. [Department of Soil Science, University of Ghana, Legon, Accra (Ghana); Zapata, F. [International Atomic Energy Agency, Vienna (Austria)]. E-mail: F.Zapata@iaea.org; Fardeau, J.C. [Departement Environnement et Agronomie, INRA, Versailles (France)

    2002-05-15

    Phosphorus deficiency is one of the major constraints for normal plant growth and crop yields in the acid soils of Ghana and therefore addition of P inputs is required for sustainable crop production. This is often difficult, if not impossible for small-scale farmers due to the high cost of mineral P fertilizers and limited access to fertilizer supplies. Direct application of finely ground phosphate rocks (PRs) and their modified forms have been recommended as alternatives for P fertilization. The direct application of the natural and modified PRs to these acid soils implies the need to predict their agronomic effectiveness of the PRs in the simplest and most cost-effective manner. In this study the classical greenhouse pot experiment was compared to the {sup 32}P isotopic kinetics laboratory method for evaluating the agronomic effectiveness of natural and modified Togo PR in six highly weathered Oxisols from southwest Ghana. In the {sup 32}P isotopic kinetics laboratory experiment the six soil samples were each fertilised at the rate of 50 mg P kg{sup -1} soil in the form of triple superphosphate (TSP), Togo PAPR-50%, and Togo PR, respectively. Controls without P amendment were also included. Isotopic exchange kinetics experiments were carried out on two sets of samples, immediately after P fertilizer additions (without incubation) and after 6 weeks of incubation under wet conditions and at a room temperature of 25 deg C. In the greenhouse pot experiment, P fertilizers in the form of Togo PR, Togo PAPR, Mali PR and TSP were each applied to the six soils at rates equivalent to 0, 30, 60, and 120 kg P ha{sup -1}, respectively. The P fertilizers were mixed with the soils and maize (Zea mays L.) variety Obatanpa was grown for 42 days before harvest. The isotopic kinetics data of the control samples indicated that 5 of the studied soils had very low P fertility status as reflected by their low P concentrations in solution (C{sub P}<0.02 mg P l{sup -1}) and low

  10. CERN Rocks

    CERN Multimedia

    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. LYOTROPIC LIQUID CRYSTALLINE BEHAVIOR OF FIVE CHITOSAN DERIVATIVES

    Institute of Scientific and Technical Information of China (English)

    Yan-ming Dong; Zhi-qiang Li

    1999-01-01

    Five chitosan derivatives, i.e. O-butyryl chitosan, O-benzoyl chitosan, N-phthaloyl chitosan, N-maleoyl chitosan and O-cyanoethyl chitosan, were prepared from chitosan. All of them had better solubilitythan chitosan, and demonstrated lyotropic liquid crystalline behavior in various solvents. The critical liquid crystalline behavior of three O-substituted chitosan derivatives was evidently different from two Nsubstituted analogues. Typical fingerprint textures of cholesteric phase were only observed in three Osubstituted derivatives. The critical concentration (v/v%) of three O-substituted derivatives does not depend on the acidity of acidic solvents.

  12. Crystalline silicotitanates for cesium/strontium removal

    Energy Technology Data Exchange (ETDEWEB)

    Brown, N.; Miller, J.; Sherman, J.

    1996-10-01

    A new class of inorganic ion exchangers called crystalline silicotitanates (CST) has been developed that exhibits very high selectivity for cesium and strontium in the highly alkaline radioactive wastes at the Hanford Site and other DOE sites. Tests have also shown that CSTs have high selectivity for cesium in acidic and neutral solutions. The ESP is supporting an effort at Sandia National Laboratories and Texas A & M University to further develop and characterize the important chemical and physical properties that will determine the applicability of CST to radioactive waste treatment at Hanford and other DOE facilities.

  13. Amorphization of Crystalline Water Ice

    CERN Document Server

    Zheng, Weijun; Kaiser, Ralf I

    2008-01-01

    We conducted a systematic experimental study to investigate the amorphization of crystalline ice by irradiation in the 10-50 K temperature range with 5 keV electrons at a dose of ~140 eV per molecule. We found that crystalline water ice can be converted partially to amorphous ice by electron irradiation. Our experiments showed that some of the 1.65-micrometer band survived the irradiation, to a degree that depends on the temperature, demonstrating that there is a balance between thermal recrystallization and irradiation-induced amorphization, with thermal recrystallizaton dominant at higher temperatures. At 50 K, recrystallization due to thermal effects is strong, and most of the crystalline ice survived. Temperatures of most known objects in the solar system, including Jovian satellites, Saturnian satellites, and Kuiper belt objects, are equal to or above 50 K, this might explain why water ice detected on those objects is mostly crystalline.

  14. Crystalline Repository Project: Technical progress report for the period October 1, 1982--May 28, 1986

    International Nuclear Information System (INIS)

    This document reports the progress made on the development of a second geologic repository in crystalline rocks during the duration of the Crystalline Repository Project from its inception in October 1982 to its termination in May 1986. The reporting elements are arranged by the work breakdown structure so that related studies are presented together. The studies are reported by the Office of Waste Technology Development (OWTD), successor to the Office of Crystalline Repository Development. OWTD is a prime contractor of the US Department of Energy (DOE) Repository Technology Program Office, itself the successor to the Crystalline Repository Project Office. The studies include work by other DOE prime contractors and by contractors to the Office of Crystalline Repository Development. 151 refs

  15. Parameterization and quantification of recharge in crystalline fractured bedrocks in Galicia-Costa (NW Spain)

    OpenAIRE

    Raposo, J. R.; Molinero, J.; Dafonte, J.

    2012-01-01

    Quantification of groundwater recharge in crystalline rocks presents great difficulties due to high heterogeneity. Traditionally these rocks have been considered with very low permeability, and their groundwater resources have been usually neglected, although they can have local importance when the bedrock presents a net of fractures well developed. Current European Water Framework Directive requires an efficient management of all groundwater resources, which begins with a proper knowledge of...

  16. Parameterization and quantification of recharge in crystalline fractured bedrocks in Galicia-Costa (NW Spain)

    OpenAIRE

    Raposo, J. R.; Molinero, J.; Dafonte, J.

    2012-01-01

    Quantifying groundwater recharge in crystalline rocks presents great difficulties due to the high heterogeneity of the underground medium (mainly, due to heterogeneity in fracture network, which determines hydraulic parameters of the bedrock like hydraulic conductivity or effective porosity). Traditionally these rocks have been considered to have very low permeability, and their groundwater resources have usually been neglected; however, they can be of local importance when the bedrock presen...

  17. Discussion on Acidic Mining Drainage Production and Prevention in Carbonate Rock Area%碳酸盐岩地区矿山酸性排水的产生及其防治初探

    Institute of Scientific and Technical Information of China (English)

    罗远红; 雷良奇; 常耀辉; 马于涛

    2011-01-01

    The sulphide in tailings produces acidic mining drainage(AMD) after a series of physical and chemical reactions with air,water,microorganisms.People once have considered that the tailings in carbonate rock areas will not cause acid pollutions because the carbonate minerals in tailings and surrounding rocks have neutralization effect.But there are serious acid pollutions in typical carbonate rock areas like Dachang of Guangxi province,Fankou and Dabaoshan of Guangdong province,Niujiaotang of Guizhou province,etc.The main cause is that in the process of carbonate mineral neutralization,the secondary minerals precipitate and adhere to the surface of carbonate minerals and stop further response,so the actual neutralization dose can not meet the theoretical value.Acidic mining drainage carries large amounts of metal ions which could bring serious damage to ecological environment and mine engineering facilities in carbonate rock areas.According to the characteristics of tailings in carbonate rock areas,the most efficient method for acidification of tailings is to adopt covering method for new tailings and permeable reactive barriers for acidified tailings.%尾矿中的硫化物在空气、水、微生物等的作用下,发生一系列的物理化学反应,形成矿山酸性排水(AMD)。在碳酸盐岩地区,由于尾矿和围岩中都含有大量对酸具有中和效应的碳酸盐矿物,于是人们一直认为碳酸盐岩地区的尾矿不存在酸污染。而如广西大厂、广东凡口及大宝山、贵州牛角塘等碳酸盐岩地区矿山的尾矿却存在着严重的酸污染,其主要原因是碳酸盐矿物在中和酸水过程中,表面会形成阻止反应进一步进行的次生包壳,碳酸盐矿物的实际中和量达不到其理论值。矿山酸性排水携带大量的重金属离子,对碳酸盐岩地区的生态环境及矿山工程设施带来严重的危害。针对碳酸盐岩地区尾矿自身的特殊性,对新建尾矿堆采用覆盖

  18. Investigation of the porosity of rocks

    International Nuclear Information System (INIS)

    Methods for characterizing the nature of rock porosity in conjunction with diffusion experiments, are amongst the primary tools used in repository-site selection investigations. At this time no experimental method, alone, is capable of giving an unambiguous picture of the narrow-aperture pore space in crystalline rock. Methods giving information on overall properties must be complemented by those having high spatial resolution; then the lateral distribution of porosity within the matrix and its association with particular mineral phases or features, such as microfissures, fissure fillings, weathered or altered mineral phases etc, and the identification of diffusion pathways in inhomogeneous rock matrices can be determined. Nonsorbing, nonelectrolytic tracers should be used when one wants to determine rock-typical properties of the internal porosity without interference of interactions with surfaces. Preliminary information on a new method fulfilling these criteria is given. Impregnating rock samples with methylmethacrylate labeled with carbon-14 which, after impregnation, was polymerized by gamma radiation, gave specimens that made preparation of sections suitable for quantification by autoradiographic methods easy. Diffusion experiments can be conducted so that labeled MMA diffuses out of rock specimens into inactive free, MMA. Additional information may be gained by leaching PMMA fractions of lower molecular weight from the matrix

  19. Draft Area Recommendation Report for the Crystalline Repository Project: Overview

    International Nuclear Information System (INIS)

    The draft Area Recommendation Report (ARR) for the Crystalline Repository Project identifies portions of crystalline rock bodies as proposed potentially acceptable sites for the Nation's second repository for deep geologic burial of high-level radioactive waste and spent nuclear fuel. This Overview provides a brief summary of that report. The US Department of Energy (DOE) evaluated available geologic and environmental data for 235 crystalline rock bodies in the North Central, Northeastern, and Southeastern Regions to identify preliminary candidate areas. The 12 proposed potentially acceptable sites are located in the States of Georgia (1), Maine (2), Minnesota (3), New Hampshire (1), North Carolina (2), Virginia (2), and Wisconsin (1). The data, analyses and rationale pertaining to the identification of the 12 proposed potentially acceptable sites are presented in the draft ARR. The analyses presented in the draft ARR demonstrate that the evidence available for each proposed potentially acceptable site supports (1) a finding that the site is not disqualified under Appendix III of the DOE Siting Guidelines and (2) a decision to proceed with the continued investigation of the site on the basis of the favorable and potentially adverse conditions identified to date. These potentially acceptable sites will be investigated and evaluated in more detail during the area phase of the siting process and considered along with other candidate sites in a progressive narrowing process to finally choose the site of the second repository in 1998

  20. Evaluation of standardized ileal digestible valine:lysine, total lysine:crude protein, and replacing fish meal, meat and bone meal, and poultry byproduct meal with crystalline amino acids on growth performance of nursery pigs from seven to twelve kilograms.

    Science.gov (United States)

    Nemechek, J E; Tokach, M D; Dritz, S S; Goodband, R D; DeRouchey, J M

    2014-04-01

    Five experiments were conducted to evaluate replacing fish meal, meat and bone meal, and poultry byproduct meal with crystalline AA for 7- to 12-kg pigs. In all experiments, pigs (PIC TR4 × 1050) were fed a common diet for 3 d postweaning, treatment diets for 14 d (d 0 to 14), and, again, a common diet for 14 d (d 14 to 28). Treatment diets were corn-soybean meal based and formulated to contain 1.30% standardized ileal digestible (SID) Lys. Experiment 1 evaluated replacing dietary fish meal with crystalline AA. For the 6 treatments, crystalline Lys, Met, Thr, Trp, Ile, Val, Gln, and Gly all increased to maintain minimum AA ratios as fish meal decreased (4.50, 3.60, 2.70, 1.80, and 0.90 to 0.00%). There was no difference in ADG, ADFI, or G:F among treatments, validating a low-CP, AA-fortified diet for subsequent experiments. Experiment 2 evaluated deleting crystalline AA from a low-CP, AA-fortified diet with 6 treatments: 1) a positive control similar to the diet validated in Exp. 1, 2) positive control with l-Ile deleted, 3) positive control with l-Trp deleted, 4) positive control with l-Val deleted, 5) positive control with l-Gln and l-Gly deleted, and 6) positive control with l-Ile, l-Trp, l-Val, l-Gln, and l-Gly deleted (NC). Pigs fed the positive control or Ile deleted diet had improved (P < 0.05) ADG and ADFI during d 0 to 14 compared with pigs fed diets with l-Trp or l-Val deleted or NC. Experiment 3 evaluated 6 treatments with total Lys:CP of 6.79, 6.92, 7.06, 7.20, 7.35, and 7.51%. Fish meal was adjusted as a source of dispensable N to achieve the target Lys:CP. There were no differences in growth performance among pigs fed different Lys:CP diets. Experiment 4 evaluated increasing SID Val:Lys with Val at 57.4, 59.9, 62.3, 64.7, 67.2, and 69.6% of Lys. Average daily gain and ADFI increased (quadratic, P < 0.01) and G:F improved (linear, P = 0.02) during d 0 to 14 as Val:Lys increased from 57.4 to 64.7%. Experiment 5 was a 2 × 3 factorial arrangement of

  1. Gas migration through salt rocks

    International Nuclear Information System (INIS)

    Salt as a host rock for a repository for radioactive waste may appear as a layered formation as observed at the WIPP site in the USA or as domed salt, which is abundant in the northern part of central Europe. Planned or actual repository sites like Gorleben, Morsleben or Asse in Germany are located in such salt domes. They have risen up in geological time from Permian salt beds until their upward movement has come to an end. Rock salt exists under geological conditions as an extremely dry material with a residual moisture content well below 1 %. Due to its crystalline nature, its permeability and porosity are very low. In addition, because of its plastic behaviour under stress salt has a high self-healing capacity. In fact, under undisturbed conditions, rock salt is considered as impermeable (permeability less than 10-22 m2). This is demonstrated impressively by brine inclusions which have been included millions of years ago and are kept in place until today. Thus, in considering conditions for two phase flow, undisturbed salt neither offers sufficient water nor appropriate hydraulic properties for scenarios involving normal two-phase flow to occur. Therefore, there is a fundamental difference to other host rock material, in that long term safety analyses for waste repositories in salt have, in general, to assume accident scenarios or some kind of faulted conditions to produce a scenario where gas production and two-phase flow become relevant. The main focus of those safety analyses is on compacted crushed salt as backfill material, possibly on seals and plugs for emplacement rooms or borehole closures and on the engineering disturbed zone (EDZ). (author)

  2. Deformation of a polydomain, smectic Liquid Crystalline Elastomer

    NARCIS (Netherlands)

    Ortiz, C; Bhargava, N; Ober, CK; Kramer, EJ

    1998-01-01

    A main-chain, polydomain, smectic liquid crystalline elastomer (LCE) was prepared by reacting the LC epoxy monomer, diglycidyl ether of 4,4'-dihydroxy-alpha-methylstilbene, with the aliphatic diacid, sebacic acid. When deformed in uniaxial tension, a "polydomain-to-monodomain" transition took place

  3. Application of water flow and geochemical models to support the remediation of acid rock drainage from the uranium mining site of Pocos de Caldas, Brazil

    International Nuclear Information System (INIS)

    Available in abstract form only. Full text of publication follows: This paper discusses the use of two numerical models (HYDRUS-2D and STEADQL-v4) for simulating water flow and relevant geochemical processes in one of the waste rock piles of the first uranium mine in Brazil, in order to facilitate the selection of appropriate remediation strategies. The long time scale required for the oxidation of sulfidic wastes (at least 600 years) implies the need to implement permanent remediation actions. The best remediation scheme should depend on the water flow regime inside the waste pile and on the geochemical processes that occur as a result of the interactions between water and the waste (especially oxidative dissolution of pyrite). Accurate modeling of the waste site, which contains a wide range of grain and rock sizes at different degrees of water saturation and is subject to reactive multicomponent transport, entails considerable physical, mathematical and numerical challenges. This paper describes the approach used to obtain a detailed representation of the system involving both unsaturated/ saturated flow (most of the physical properties of the waste were estimated from measured data) and the geochemical network reactions (including equilibrium and kinetics reactions). (authors)

  4. 中低品位磷矿生产磷酸联产石膏晶须技术现状%Present Status of Technology for Co-Production of Phosphoric Acid and Gypsum Whiskers from Medium-and Low-Grade Phosphate Rock

    Institute of Scientific and Technical Information of China (English)

    石学勇; 王金铭

    2013-01-01

    阐述了中低品位磷矿生产磷酸联产石膏晶须工艺技术的意义,并介绍了该工艺技术的基本原理和应用前景.采用盐酸和硫酸萃取磷矿并添加活性添加剂提高磷矿萃取速度和磷矿分解率,分离酸不溶物和部分杂质(铁、铝、镁),然后采用硫酸脱钙获得石膏晶须和磷酸,为中低品位磷矿综合利用提供了一条可行的途径.%A description is given of the technology for the co-production of phosphoric acid and gypsum whiskers from medium- and low-grade phosphate rock and its significance, also the fundamental principles of the technology and prospects for its use. Hydrochloric acid and sulfuric acid react with phosphate rock with the addition of an active additive to increase the extraction rate and decomposition rate of the rock, the acid-insolubles and some impurities ( iron, aluminum and magnesium) are separated out, and then sulfuric acid is used for decalcification to obtain phosphoric acid and gypsum whiskers, thereby providing a feasible route for comprehensive utilization of medium-and low-grade phosphate rock.

  5. Nanostructures having crystalline and amorphous phases

    Science.gov (United States)

    Mao, Samuel S; Chen, Xiaobo

    2015-04-28

    The present invention includes a nanostructure, a method of making thereof, and a method of photocatalysis. In one embodiment, the nanostructure includes a crystalline phase and an amorphous phase in contact with the crystalline phase. Each of the crystalline and amorphous phases has at least one dimension on a nanometer scale. In another embodiment, the nanostructure includes a nanoparticle comprising a crystalline phase and an amorphous phase. The amorphous phase is in a selected amount. In another embodiment, the nanostructure includes crystalline titanium dioxide and amorphous titanium dioxide in contact with the crystalline titanium dioxide. Each of the crystalline and amorphous titanium dioxide has at least one dimension on a nanometer scale.

  6. 晶体氨基酸替代鱼粉蛋白对半滑舌鳎稚鱼消化酶和代谢酶活力的影响%EFFECTS OF FISH MEAL REPLACEMENT WITH CRYSTALLINE AMINO ACID ON DIGESTIVE AND METABOLIC ENZYMES OF TONGUE SOLE (CYNOGLOSSUS SEMILAEVIS GÜNTHER, 1873) LARVAE

    Institute of Scientific and Technical Information of China (English)

    张珊; 艾庆辉; 麦康森; 徐玮; 韩冰

    2014-01-01

    The study was conducted to investigate the effects of replacement of fish meal protein by crystalline amino acids on digestive enzymes and metabolism enzymes in tongue sole larvae. Five isoproteic and isolipidic diets were formulated to replace 0%, 25%, 50%, 75%, 100% fish meal (0% CAA, 25% CAA, 50% CAA, 75% CAA and 100%CAA) respectively. At the replacement level of 25%, another diet was formulated with amino acids coated with tri-palmitin (C-25%CAA). Each micro diet was randomly fed to triplicate groups of fish, and each group had 150 fish. The results showed that the activities of trypsin significantly decreased with increasing dietary crystalline amino acids, but there were no significant differences between C-25%CAA and 0%CAA (P>0.05). The ratio of Trypsin(I) to Trypsin(P) significantly decreased with increasing dietary crystalline amino acids, and 0%CAA was significantly higher than 75%CAA and 100%CAA. The activities of amylase significantly increased with increasing dietary crystalline amino acids. The activities of leucine-amino peptidase and alkaline-phosphatase in intestine and purified brush border membrane of intestine significantly decreased with increasing dietary crystalline amino acids, but no significant differences were ob-served between C-25% CAA and 0% CAA (P>0.05). Glutamic-pyruvic transaminase and Glutamic-oxalacetic transa-minease significantly increased with increasing dietary crystalline amino acids. In conclusion, crystalline amino acids in the micro diet significantly influenced the digestive and metabolic enzymes of tongue sole larvae. In the replacement level of 25%, Comparing with 25% CAA group crystalline amino acids coated with tripalmitin (C-25% CAA) could promote the development of digestion system in tongue sole larvae.%为研究人工微颗粒饲料中晶体氨基酸替代鱼粉蛋白对半滑舌鳎(Cynoglossus semilaevis Günther)稚鱼消化酶和代谢酶活力的影响,以晶体氨基酸混合物分别替代0%、25%、50%、75

  7. Preliminary review of Precambrian Shield rocks for potential waste repository

    Energy Technology Data Exchange (ETDEWEB)

    Yardley, D.H.; Goldich, S.S.

    1975-11-01

    This review of the Canadian Shield is primarily concerned with the part (such as in the Lake Superior region) that is seismically the least active of the North American continent. The crystalline metamorphic and igneous rocks of the more stable elements of the shield provide excellent possibilities for dry excavations suitable for long-term storage of radioactive waste materials. (DLC)

  8. Reconnaissance for radioactive rocks in the Paulo Afonso Region, Bahia, Brazil

    Science.gov (United States)

    Haynes, Donald D.; Mau, Henry

    1958-01-01

    Ground and air traverses were made to the northwest, north and northeast of Paulo Afonso, Bahia, Brazil, covering Precambrian crystalline rocks and sedimentary rocks of the Jatoba series of Jurassic or Cretaceous age. No important radioactivity anomalies were found; samples from the two strongest anomalies had an equivalent uranium-oxide content of 0.002 percent and 0.006 percent.

  9. Uranium distribution in mineral phases of rock by sequential extraction procedure

    International Nuclear Information System (INIS)

    A sequential extraction procedure was used to study the distribution of uranium in mineral phases of rock at the Koongarra uranium deposit (Northern Territory of Australia). This work forms a part of the natural analogue study carried out in the International Alligator Rivers Analogue Project, which is being sponsored by the OECD/NEA. The following mineral phases: adsorbed trace material and carbonate minerals, amorphous iron minerals and secondary uranium minerals, crystalline iron minerals, clay minerals, and remaining resistant mineral phases, were extracted successively by treatment with: 1 M sodium acetate (pH=5) (Morgan's solution). Tamm's acid oxalate (TAO) (pH=3), citrate-dithionite-bicarbonate (CDB), 6 M hydrochloric acid, and fusion respectively. The majority of uranium in samples from the secondary ore body at Koongarra was contained in crystalline iron minerals (42-60%). In the primary or body, the uranium distribution between mineral phases varies with depth. About 70% of the total uranium was incorporated with the Tamm's extractable mineral phases, in the weathered region of the drill hole DDH1 (19.4-20.5 m). In the deeper region of the drill hole DDH2 (33.0-34.3 m), most of the uranium was extractable with 6 M HCl. The 234U/238U activity ratios in each extraction are discussed on the basis of the alpha recoil effect, which occurs with the decay of 238U through 234Th to 234U. (orig.)

  10. Biomimetic processing of oriented crystalline ceramic layers

    Energy Technology Data Exchange (ETDEWEB)

    Cesarano, J.; Shelnutt, J.A.

    1997-10-01

    The aim of this project was to develop the capabilities for Sandia to fabricate self assembled Langmuir-Blodgett (LB) films of various materials and to exploit their two-dimensional crystalline structure to promote the growth of oriented thin films of inorganic materials at room temperature. This includes the design and synthesis of Langmuir-active (amphiphilic) organic molecules with end groups offering high nucleation potential for various ceramics. A longer range goal is that of understanding the underlying principles, making it feasible to use the techniques presented in this report to fabricate unique oriented films of various materials for electronic, sensor, and membrane applications. Therefore, whenever possible, work completed in this report was completed with the intention of addressing the fundamental phenomena underlying the growth of crystalline, inorganic films on template layers of highly organized organic molecules. This problem was inspired by biological processes, which often produce exquisitely engineered structures via templated growth on polymeric layers. Seashells, for example, exhibit great toughness owing to their fine brick-and-mortar structure that results from templated growth of calcium carbonate on top of layers of ordered organic proteins. A key goal in this work, therefore, is to demonstrate a positive correlation between the order and orientation of the template layer and that of the crystalline ceramic material grown upon it. The work completed was comprised of several parallel efforts that encompassed the entire spectrum of biomimetic growth from solution. Studies were completed on seashells and the mechanisms of growth for calcium carbonate. Studies were completed on the characterization of LB films and the capability developed for the in-house fabrication of these films. Standard films of fatty acids were studied as well as novel polypeptides and porphyrins that were synthesized.

  11. Computer construction and analysis of protein models of the mutant γD-crystallin gene

    Institute of Scientific and Technical Information of China (English)

    YAO Ke; SUN Zhao-hui; SHENTU Xing-chao; WANG Kai-jun; TAN Jian

    2005-01-01

    Background γD-crystallin plays an important role in human cataract formation. Being highly stable, γD-crystallin proteins are composed of two domains. In this study we constructed and analyzed protein models of the mutant γD-crystallin gene, which caused a special fasciculiform congenital cataract affecting a large Chinese family. Methods γD-crystallin protein structure was predicted by Swiss-Model software using bovine γD-crystallin as a template and Prospect software using human βb2-crystallin as a template. The models were observed with a Swiss-Pdb viewer.Results The mutant γD-crystallin structure predicted by the Swiss-Model software showed that proline23 was an exposed surface residue and P23T change made a decreased hydrogen bond distance between threonine23 and asparagine49. The mutant γD-crystallin structure predicted by the Prospect software showed that the P23T change exerted a significant effect on the protein's tertiary structure and yielded hydrogen bonds with aspartic acid21, asparagine24, asparagine49 and serine74.Conclusion The mutant γD-crystallin gene has a significant effect on the protein's tertiary structure, supporting that alteration of γ-crystallin plays an important role in human cataract formation.

  12. 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.…

  13. The rock diet

    OpenAIRE

    Fordyce, Fiona; Johnson, Chris

    2002-01-01

    You may think there is little connection between rocks and our diet, indeed a serving of rocks may sound very unappetising! But rocks are a vital source of the essential elements and minerals we need to keep us healthy, such as calcium for healthy teeth and bones.

  14. 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...

  15. 模拟酸雨条件下石灰土-碳酸盐岩体系的碳汇效应%Carbon sink effect of simulated acid rain in lime soil and carbonate rock system

    Institute of Scientific and Technical Information of China (English)

    李春龙; 赵家梅; 龙偲; 陈中吉; 周运超; 张春来

    2014-01-01

    为揭示不同酸度降雨对石灰土-碳酸盐岩体系内岩溶碳汇效应的影响,以贵阳市花溪区历史降水量为参照,选取贵阳市青岩镇纯灰岩发育土壤与贵阳市花溪水库三叠纪大冶组纯灰岩为样本进行淋溶试验。测定了6个月时长内不同酸度降水﹑不同土壤深度下模拟石灰土-碳酸盐岩体系降水淋出液的 HCO-3﹑DOC含量和土壤呼吸速率,研究了模拟酸雨对石灰土-石灰岩体系碳汇的影响。结果表明:(1)在土壤深度10~50 cm 匀质状态的样本中,随着土壤厚度的增加,淋出液中 HCO-3含量逐渐增大﹑DOC含量逐渐减小﹑土壤呼吸速率逐渐增大,显示出土壤厚度对石灰土-碳酸盐岩体系的碳汇效应有着明显的影响;(2)在 pH=3.5~6.8的范围内,降水酸度的增强可以抑制岩溶作用与有机碳的溶解,并降低岩溶碳汇效应;(3)在日降水量90~230 mm 范围内,随着降水量的增大碳汇效应也会随之增强。%In order to investigate the influence of rainfall acidity on the carbon sink in a lime soil and carbonate rock system,a leaching test was conducted using lime soil sample developed in pure limestone in Qingyan town and a pure limestone sample of Triassic Daye formation from Huaxi reservoir,Guiyang,comparing to the historical precipitation in Huaxi district,Guiyang.The influence of simulated acid rain on lime soil and the limestone system carbon sink was studied by measuring the HCO-3 content,DOC in the leachates and the soil respiration rate in the lime soil and carbonate rocks system leached over six-months using a range of pre-cipitation acidities and at various depths in the soil.The results showed that,(1)in the homogeneous sample in the soil of 10-50 cm deep ,the content of HCO-3 increased with increased thickness of soil,however the DOC content decreased and the rate of soil respiration increased,indicating that soil thickness significantly affected the carbon sink in

  16. The Guadalupian-Lopingian boundary mudstones at Chaotian (SW China) are clastic rocks rather than acidic tuffs: Implication for a temporal coincidence between the end-Guadalupian mass extinction and the Emeishan volcanism

    Science.gov (United States)

    He, Bin; Xu, Yi-Gang; Zhong, Yu-Ting; Guan, Jun-Peng

    2010-09-01

    Previous studies on the temporal link between the end-Guadalupian mass extinction event and Emeishan flood volcanism were mainly based on geochronological and bio- and chemostratigraphic correlation techniques (Wignall et al., 2009). The absence of material-based hard evidence that directly links the extinction with the Emeishan volcanism remains a major obstacle regardless of the indication of coincidence in timing (Isozaki et al., 2007). The Emeishan basalts overlie Permian platform carbonates that may contain a record of the end-Guadalupian mass extinction and erosional product of this province. This paper presents mineralogy and geochemistry of mudstones from the Guadalupian-Lopingian Boundary (G-LB) at Chaotian, SW China. Results indicate that these G-LB mudstones are not air-fall acidic tuff as previously thought, but likely represent clastic rocks derived from erosional deposits of the Emeishan large igneous province (ELIP). Mudstones of the lower part (Group 1) have a geochemical affinity to the Emeishan felsic volcanic rocks, whereas mudstones of the upper part (Group 2) are compositionally akin to mafic components of the Emeishan traps. This chemostratigraphic sequence resembles the Xuanwei Formation which sits on the Emeishan basalts (He et al., 2007). These data therefore indicate that the lower part of the mudstones at the Chaotian G-LB section, the lowermost part of Xuanwei and Longtan Formations and the Emeishan felsic extrusives broadly constitute an isochron horizon throughout the ELIP and adjacent region, suggesting a short duration for the Emeishan volcanism. A temporal coincidence between Emeishan volcanism and the end-Guadalupian mass extinction are therefore inferred thus providing support for a cause-and-effect relationship.

  17. The use of 32P radioisotope techniques for evaluating the relative agronomic effectiveness of phosphate rock materials in a soybean-maize crop rotation in acid soils of Thailand

    International Nuclear Information System (INIS)

    A series of greenhouse experiments was conducted over three years to evaluate the relative agronomic effectiveness (RAE) of phosphate rock materials in a soybean - maize crop sequence, using 32P isotope dilution techniques. For the first two years, the crops were grown in a pot experiment in four acid soils of Thailand. In the first year, four increasing rates of TSP and one rate of four phosphate rocks (PRs) were used. The PRs used were Algerian PR, North Carolina PR, Petchaburi PR, and Ratchaburi PR. Soybean did not respond to P application from TSP, while there was good response in maize which was planted after soybean (1st residual effect). The percent P derived from TSP or PR fertilizer (%Pdff) had the following order: Warin soil > Mae Tang soil > Rangsit soil > Pakchong soil for soybean and Warin soil > Pakchong soil > Rangsit soil > Mae Tang soil for maize. In the second year, the soybean - maize rotation was replanted to study the residual effect of TSP and PRs, both applied at 180 mg P kg-1 . No significant response of soybean and maize to TSP was found in terms of dry matter yield. In terms of %Pdff and %RAE the soils ranked as follows: Rangsit soil > Pakchong soil Mae Tang soil > Warin soil for soybean and Warin soil > Rangsit soil > Mae Tang > Pakchong soil for maize. Both crops absorbed more P from TSP than from PRs. The %RAE in the 2nd year experiment was higher than %RAE in the 1st year In the third year, TSP and two PRs were applied at one P rate to Pakchong and Warin soils. The applied PRs were North Carolina PR (NCPR) and Lamphun phosphate rock (LPPR). PRs were applied either alone or in combination with TSP (50:50). Soybean was planted first, followed by maize. The P-response in terms of dry matter yield and %Pdff was highly significant in both soils. The RAE ranked as follows: TSP > NCPR + TSP > LPPR + TSP > NCPR > LPPR. Maize showed the same trend in RAE as soybean in both soils. The RAE for both crops was highest in Warin soil. (author)

  18. Boring and Sealing Rock with Directed Energy Millimeter-Waves

    Science.gov (United States)

    Woskov, P.; Einstein, H. H.; Oglesby, K.

    2015-12-01

    Millimeter-wave directed energy is being investigated to penetrate into deep crystalline basement rock formations to lower well costs and to melt rocks, metals, and other additives to seal wells for applications that include nuclear waste storage and geothermal energy. Laboratory tests have established that intense millimeter-wave (MMW) beams > 1 kW/cm2 can melt and/ or vaporize hard crystalline rocks. In principle this will make it possible to create open boreholes and a method to seal them with a glass/ceramic liner and plug formed from the original rock or with other materials. A 10 kW, 28 GHz commercial (CPI) gyrotron system with a launched beam diameter of about 32 mm was used to heat basalt, granite, limestone, and sandstone specimens to temperatures over 2500 °C to create melts and holes. A calibrated 137 GHz radiometer view, collinear with the heating beam, monitored real time peak rock temperature. A water load surrounding the rock test specimen primarily monitored unabsorbed power at 28 GHz. Power balance analysis of the laboratory observations shows that the temperature rise is limited by radiative heat loss, which would be expected to be trapped in a borehole. The analysis also indicates that the emissivity (absorption efficiency) in the radiated infrared range is lower than the emissivity at 28 GHz, giving the MMW frequency range an important advantage for rock melting. Strength tests on one granite type indicated that heating the rock initially weakens it, but with exposure to higher temperatures the resolidified black glassy product regains strength. Basalt was the easiest to melt and penetrate, if a melt leak path was provided, because of its low viscosity. Full beam holes up to about 50 mm diameter (diffraction increased beam size) were achieved through 30 mm thick basalt and granite specimens. Laboratory experiments to form a seal in an existing hole have also been carried out by melting rock and a simulated steel casing.

  19. The crystalline sponge method updated

    Science.gov (United States)

    Hoshino, Manabu; Khutia, Anupam; Xing, Hongzhu; Inokuma, Yasuhide; Fujita, Makoto

    2016-01-01

    Crystalline sponges are porous metal complexes that can absorb and orient common organic molecules in their pores and make them observable by conventional X-ray structure analysis (crystalline sponge method). In this study, all of the steps in the crystalline sponge method, including sponge crystal preparation, pore–solvent exchange, guest soaking, data collection and crystallographic analysis, are carefully examined and thoroughly optimized to provide reliable and meaningful chemical information as chemical crystallography. Major improvements in the method have been made in the guest-soaking and data-collection steps. In the soaking step, obtaining a high site occupancy of the guest is particularly important, and dominant parameters for guest soaking (e.g. temperature, time, concentration, solvents) therefore have to be optimized for every sample compound. When standard conditions do not work, a high-throughput method is useful for efficiently optimizing the soaking conditions. The X-ray experiments are also carefully re-examined. Significant improvement of the guest data quality is achieved by complete data collection at high angle regions. The appropriate disorder treatment of the most flexible ZnI2 portions of the host framework and refinement of the solvents filling the remaining void are also particularly important for obtaining better data quality. A benchmark test for the crystalline sponge method toward an achiral molecule is proposed with a guaiazulene guest, in which the guest structure (with ∼ 100% site occupancy) is refined without applying any restraints or constraints. The obtained data quality with R int = 0.0279 and R 1 = 0.0379 is comparable with that of current conventional crystallographic analysis for small molecules. Another benchmark test for this method toward a chiral molecule is also proposed with a santonin guest. The crystallographic data obtained [R int = 0.0421, R 1 = 0.0312, Flack (Parsons) = −0.0071 (11)] represents the

  20. Overview of Crystalline Color Superconductors

    CERN Document Server

    Mannarelli, Massimo

    2015-01-01

    Inhomogeneous phases may appear when a stress is applied to a system and the system can minimize the free energy breaking the rotational invariance. Various examples are known in Nature of this sort, as the paramagnetic to ferromagnetic phase transition, or the fluid/solid phase transition. If the rotational symmetry is broken down to a discrete symmetry, the system is typically named a crystal. We breifly review crystalline color superconductors, which arise in cold quark matter with mismatched Fermi spheres.

  1. The crystalline sponge method updated

    Directory of Open Access Journals (Sweden)

    Manabu Hoshino

    2016-03-01

    Full Text Available Crystalline sponges are porous metal complexes that can absorb and orient common organic molecules in their pores and make them observable by conventional X-ray structure analysis (crystalline sponge method. In this study, all of the steps in the crystalline sponge method, including sponge crystal preparation, pore–solvent exchange, guest soaking, data collection and crystallographic analysis, are carefully examined and thoroughly optimized to provide reliable and meaningful chemical information as chemical crystallography. Major improvements in the method have been made in the guest-soaking and data-collection steps. In the soaking step, obtaining a high site occupancy of the guest is particularly important, and dominant parameters for guest soaking (e.g. temperature, time, concentration, solvents therefore have to be optimized for every sample compound. When standard conditions do not work, a high-throughput method is useful for efficiently optimizing the soaking conditions. The X-ray experiments are also carefully re-examined. Significant improvement of the guest data quality is achieved by complete data collection at high angle regions. The appropriate disorder treatment of the most flexible ZnI2 portions of the host framework and refinement of the solvents filling the remaining void are also particularly important for obtaining better data quality. A benchmark test for the crystalline sponge method toward an achiral molecule is proposed with a guaiazulene guest, in which the guest structure (with ∼ 100% site occupancy is refined without applying any restraints or constraints. The obtained data quality with Rint = 0.0279 and R1 = 0.0379 is comparable with that of current conventional crystallographic analysis for small molecules. Another benchmark test for this method toward a chiral molecule is also proposed with a santonin guest. The crystallographic data obtained [Rint = 0.0421, R1 = 0.0312, Flack (Parsons = −0.0071 (11

  2. The crystalline sponge method updated.

    Science.gov (United States)

    Hoshino, Manabu; Khutia, Anupam; Xing, Hongzhu; Inokuma, Yasuhide; Fujita, Makoto

    2016-03-01

    Crystalline sponges are porous metal complexes that can absorb and orient common organic molecules in their pores and make them observable by conventional X-ray structure analysis (crystalline sponge method). In this study, all of the steps in the crystalline sponge method, including sponge crystal preparation, pore-solvent exchange, guest soaking, data collection and crystallographic analysis, are carefully examined and thoroughly optimized to provide reliable and meaningful chemical information as chemical crystallography. Major improvements in the method have been made in the guest-soaking and data-collection steps. In the soaking step, obtaining a high site occupancy of the guest is particularly important, and dominant parameters for guest soaking (e.g. temperature, time, concentration, solvents) therefore have to be optimized for every sample compound. When standard conditions do not work, a high-throughput method is useful for efficiently optimizing the soaking conditions. The X-ray experiments are also carefully re-examined. Significant improvement of the guest data quality is achieved by complete data collection at high angle regions. The appropriate disorder treatment of the most flexible ZnI2 portions of the host framework and refinement of the solvents filling the remaining void are also particularly important for obtaining better data quality. A benchmark test for the crystalline sponge method toward an achiral molecule is proposed with a guaiazulene guest, in which the guest structure (with ∼ 100% site occupancy) is refined without applying any restraints or constraints. The obtained data quality with R int = 0.0279 and R 1 = 0.0379 is comparable with that of current conventional crystallographic analysis for small molecules. Another benchmark test for this method toward a chiral molecule is also proposed with a santonin guest. The crystallographic data obtained [R int = 0.0421, R 1 = 0.0312, Flack (Parsons) = -0.0071 (11)] represents the

  3. Biocompatibility of crystalline opal nanoparticles

    Directory of Open Access Journals (Sweden)

    Hernández-Ortiz Marlen

    2012-10-01

    Full Text Available Abstract Background Silica nanoparticles are being developed as a host of biomedical and biotechnological applications. For this reason, there are more studies about biocompatibility of silica with amorphous and crystalline structure. Except hydrated silica (opal, despite is presents directly and indirectly in humans. Two sizes of crystalline opal nanoparticles were investigated in this work under criteria of toxicology. Methods In particular, cytotoxic and genotoxic effects caused by opal nanoparticles (80 and 120 nm were evaluated in cultured mouse cells via a set of bioassays, methylthiazolyldiphenyl-tetrazolium-bromide (MTT and 5-bromo-2′-deoxyuridine (BrdU. Results 3T3-NIH cells were incubated for 24 and 72 h in contact with nanocrystalline opal particles, not presented significant statistically difference in the results of cytotoxicity. Genotoxicity tests of crystalline opal nanoparticles were performed by the BrdU assay on the same cultured cells for 24 h incubation. The reduction of BrdU-incorporated cells indicates that nanocrystalline opal exposure did not caused unrepairable damage DNA. Conclusions There is no relationship between that particles size and MTT reduction, as well as BrdU incorporation, such that the opal particles did not induce cytotoxic effect and genotoxicity in cultured mouse cells.

  4. Development of a methodology for analysis of the crystalline quality of single crystals

    International Nuclear Information System (INIS)

    This work aims to establish a methodology for the analysis of the crystalline quality of single crystals. It shows that from neutron diffraction tri dimensional rocking curves it is possible to determine the intrinsic full widths at half maximum (FWHM) of the crystalline domains of a crystal, as well as the relative intensities of such domains and the angular distances between them. For the development of the method, a tridimensional I x ω x χ rocking curve has been obtained with neutrons from a mosaic aluminum crystal. The intensity I was measured as rocking curves by turning the crystal around the ω-axis of a goniometer, one curve for each angular position χ obtained by step-scanning this angle in a convenient interval. The set of individual bidimensional I x ω rocking curves formed the tridimensional I x ω x χ rocking curve for the aluminum crystal. The tridimensional rocking curve was fitted by Gaussians and deconvolved from the instrumental broadening in both directions ω and χ. The instrumental broadenings were obtained with a perfect lithium fluoride (LiF) crystal from rocking curves measured around the ω and χ-axes. Owing to an enhanced Lorentz factor in direction χ, which excessively enlarged the rocking curves in that direction, the χ scale had to be shrunk by a correction factor. The shrinkage turned the FWHM of domains in such direction equivalent to those found in direction ω. The construction of a contour map with individualized domains, on the basis of the tridimensional rocking curve of the aluminum crystal, made it easier to determine the characteristics of each domain. This contour map showed five domains. They were characterized in relation to the FWHM, relative intensity and angular distance between them. (author)

  5. PROPERTIES AND MICROSTRUCTURE OF AROMATIC LIQUID CRYSTALLINE COPOLYESTERS

    Institute of Scientific and Technical Information of China (English)

    WANG Yong; WU Dacheng; LI Ruixia

    1997-01-01

    The properties and structures of thermotropical liquid crystalline copolyesters based on p-hydroxybenzoic acid (PHBA), terephthalic acid (TPA) and biaphenol A (BPA) were studied by DSC, WAXD, hot stage polarized microscopy and NMR. It was found that most of the copolyesters were soluble in many common organic solvents. The copolyesters had low Tm/Tf values and a broad range of liquid crystal phase, making the polymers readily melt-processable. The effects of annealing at different temperatures on the copolyester containing 33% PHBA were also discussed. It was noted that annealing at ca. 200℃ (below Tc - n) could lead to the increasing of the crystallinity of the copolyester while the microstructure and sequence structure had not changed. Annealing at ca. 280℃ (near Tc - n) could bring a change of crystal and sequence structure and simultaneously made the microdomains be ordered more perfectly.

  6. Bacterial adhesion on amorphous and crystalline metal oxide coatings

    Energy Technology Data Exchange (ETDEWEB)

    Almaguer-Flores, Argelia [Facultad de Odontología, División de Estudios de Posgrado e Investigación, Universidad Nacional Autónoma de México, Circuito exterior s/n, Ciudad Universitaria, 04510 México D.F. (Mexico); Silva-Bermudez, Phaedra, E-mail: suriel21@yahoo.com [Unidad de Ingeniería de Tejidos, Terapia Celular y Medicina Regenerativa, Instituto Nacional de Rehabilitación, Calzada México-Xochimilco No. 289, Col. Arenal de Guadalupe, 14389 México D.F. (Mexico); Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Circuito Exterior s/n, Ciudad Universitaria, 04510 México D.F. (Mexico); Galicia, Rey; Rodil, Sandra E. [Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Circuito Exterior s/n, Ciudad Universitaria, 04510 México D.F. (Mexico)

    2015-12-01

    Several studies have demonstrated the influence of surface properties (surface energy, composition and topography) of biocompatible materials on the adhesion of cells/bacteria on solid substrates; however, few have provided information about the effect of the atomic arrangement or crystallinity. Using magnetron sputtering deposition, we produced amorphous and crystalline TiO{sub 2} and ZrO{sub 2} coatings with controlled micro and nanoscale morphology. The effect of the structure on the physical–chemical surface properties was carefully analyzed. Then, we studied how these parameters affect the adhesion of Escherichia coli and Staphylococcus aureus. Our findings demonstrated that the nano-topography and the surface energy were significantly influenced by the coating structure. Bacterial adhesion at micro-rough (2.6 μm) surfaces was independent of the surface composition and structure, contrary to the observation in sub-micron (0.5 μm) rough surfaces, where the crystalline oxides (TiO{sub 2} > ZrO{sub 2}) surfaces exhibited higher numbers of attached bacteria. Particularly, crystalline TiO{sub 2}, which presented a predominant acidic nature, was more attractive for the adhesion of the negatively charged bacteria. The information provided by this study, where surface modifications are introduced by means of the deposition of amorphous or crystalline oxide coatings, offers a route for the rational design of implant surfaces to control or inhibit bacterial adhesion. - Highlights: • Amorphous (a) and crystalline (c) TiO{sub 2} and ZrO{sub 2} coatings were deposited. • The atomic ordering influences the coatings surface charge and nano-topography. • The atomic ordering modifies the bacterial adhesion for the same surface chemistry. • S. aureus adhesion was lower on a-TiO{sub 2} and a-ZrO{sub 2} than on their c-oxide counterpart. • E. coli adhesion on a-TiO{sub 2} was lower than on the c-TiO{sub 2}.

  7. Hungry for Rocks

    Science.gov (United States)

    2004-01-01

    This image from the Mars Exploration Rover Spirit hazard identification camera shows the rover's perspective just before its first post-egress drive on Mars. On Sunday, the 15th martian day, or sol, of Spirit's journey, engineers drove Spirit approximately 3 meters (10 feet) toward its first rock target, a football-sized, mountain-shaped rock called Adirondack (not pictured). In the foreground of this image are 'Sashimi' and 'Sushi' - two rocks that scientists considered investigating first. Ultimately, these rocks were not chosen because their rough and dusty surfaces are ill-suited for grinding.

  8. Fatty acid profiles of phyllosoma larvae of western rock lobster (Panulirus cygnus) in cyclonic and anticyclonic eddies of the Leeuwin Current off Western Australia

    Science.gov (United States)

    Wang, M.; O'Rorke, R.; Waite, A. M.; Beckley, L. E.; Thompson, P.; Jeffs, A. G.

    2014-03-01

    The recent dramatic decline in settlement in the population of the spiny lobster, Panulirus cygnus, may be due to changes in the oceanographic processes that operate offshore of Western Australia. It has been suggested that this decline could be related to poor nutritional condition of the post-larvae, especially lipid which is accumulated in large quantities during the preceding extensive pelagic larval stage. The current study focused on investigations into the lipid content and fatty acid (FA) profiles of lobster phyllosoma larvae from three mid to late stages of larval development (stages VI, VII, VIII) sampled from two cyclonic and two anticyclonic eddies of the Leeuwin Current off Western Australia. The results showed significant accumulation of lipid and energy storage FAs with larval development regardless of location of capture, however, larvae from cyclonic eddies had more lipid and FAs associated with energy storage than larvae from anticyclonic eddies. FA food chain markers from the larvae indicated significant differences in the food webs operating in the two types of eddy, with a higher level of FA markers for production from flagellates and a lower level from copepod grazing in cyclonic versus anticyclonic eddies. The results indicate that the microbial food web operating in cyclonic eddies provides better feeding conditions for lobster larvae despite anticyclonic eddies being generally more productive and containing greater abundances of zooplankton as potential prey for lobster larvae. Gelatinous zooplankton, such as siphonophores, may play an important role in cyclonic eddies by accumulating dispersed microbial nutrients and making them available as larger prey for phyllosoma. The markedly superior nutritional condition of lobster larvae feeding in the microbial food web found in cyclonic eddies, could greatly influence their subsequent settlement and recruitment to the coastal fishery.

  9. Research on information model for metallogenic specialization of the intermediate-acid magmatic rocks in nanling region: a case of hydrothermal uranium deposit and hydrothermal tungsten and tin deposit

    International Nuclear Information System (INIS)

    Based on geochemistry analysis data of Nanling granite massifs, according to the granite hydrothermal mineralization principle, the article initially proposes the metallogenic specialization factor group target system using GIS geo-information model, establishes metallogenic specialization information model of the uranium and the tungsten mineral intrusions. According to mineralization granite rock element geochemical behavior and magmatic evolution, the paper suggests the measure that metallogenic specialization influence factor will divided into the acidity factor group, the alkalinity factor group, magmatic fractionation factor group, oxidation reduction factor group, rare-earth element factor group, source area factor group, geostructure environment factor group and so on. The paper selects the best factor group meeting the mechanism of mineralization geological and geochemical principles by using kind of statistical analysis model analyses the space and intrinsic relations of some factor. On the basis of the above aspects, it forecasts undistinguished granite massifs by using the model and the criterion. The result accords with geological fact, indicates that metallogenic specialization information model has objectivity and operability, realizes metallogenic specialization quantitative appraisal, and provides a scientific basis further distinguished the ore-bearing granite massifs. (authors)

  10. 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.

  11. Siliceous microfossil extraction from altered Monterey rocks

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, C.O.; Casey, R.E.

    1986-04-01

    Samples of altered Monterey rocks of differing lithologies were processed by various methods to develop new techniques for extracting siliceous microfossils. The preliminary use of thin sections made from the same rocks reduced the number of probable samples (samples worth further processing) by about one-third. Most of the siliceous microfossils contained in altered Monterey rocks appear to be highly recrystallized and are extremely fragile; however, some contained silicified and silica-infilled radiolarians and planktonic and benthonic foraminifera, which are very tough. In general the most useful techniques were gently hydrochloric acid, hydrogen peroxide, formic acid, monosodium glutamate, and regular siliceous microfossil extraction techniques. Unsuccessful techniques and a new siliceous microfossil flotation technique are also documented.

  12. Saline groundwater in crystalline bedrock

    International Nuclear Information System (INIS)

    The State-of-art report describes research made on deep saline groundwaters and brines found in crystalline bedrock, mainly in site studies for nuclear waste disposal. The occurrence, definitions and classifications of saline groundwaters are reviewed with a special emphasis on the different theories concerning the origins of saline groundwaters. Studies of the saline groundwaters in Finland and Sweden have been reviewed more thoroughly. Also the mixing of different bodies of groundwaters, observations of the contact of saline groundwaters and permafrost, and the geochemical modelling of saline groundwaters as well as the future trends of research have been discussed. (orig.)

  13. Heterogeneity of Parent Rocks and Its Constraints on Geochemical Criteria in Weathering Crusts of Carbonate Rocks

    Institute of Scientific and Technical Information of China (English)

    WANG Shijie; FENG Zhigang

    2004-01-01

    Owing to the low contents of their acid-insoluble components, carbonate rocks tend to decrease sharply in volume in association with the formation of weathering crust. The formation of a 1 m-thick weathering crust would usually consume more than ten meters to several tens of meters of thickness of parent rocks. The knowledge of how to identify the homogeneity of parent rocks is essential to understand the formation mechanism of weathering crust in karst regions,especially that of thick-layered red weathering crust. In this work the grain-size analyses have demonstrated that the three profiles studied are the residual weathering crust of carbonate rocks and further showed that there objectively exists the heterogeneity of parent rocks in the three studied weathering crusts. The heterogeneity of parent rocks can also be reflected in geochemical parameters of major elements, just as the characteristics of frequency plot of grain-size distribution.Conservative trace element ratios Zr/Hf and Nb/Ta are proven to be unsuitable for tracing the heterogeneity of parent rocks of weathering crust, but its geochemical mechanism is unclear. The authors strongly suggest in this paper that the identification of the homogeneity of parent rocks of weathering crust in karst regions is of prime necessity.

  14. Tailoring Crystallinity of Electrospun Plla Fibres by Control of Electrospinning Parameters

    Directory of Open Access Journals (Sweden)

    Olubayode Ero-Phillips

    2012-06-01

    Full Text Available Poly(L-lactic acid (PLLA fibers were fabricated by electrospinning. The effects of various electrospinning process parameters on the thermal properties, especially the crystallinity of the electrospun fibers were investigated. Thermal analysis of the fibers revealed that they exhibited degree of crystallinity ranging from 23% to 46% while that for the as-received granules was approximately 37%, suggesting that the crystallinity of electrospun PLLA fibres can be controlled by optimizing the electrospinning process. This finding is very important because crystallinity affects polymer properties such as degradation, stiffness, yield stress, modulus and tensile strength, solubility, optical and electrical properties which will in turn affect the behavior of these materials when they are utilized in energy, environment, defense and security applications. The results presented in this paper show that the degree of crystallinity of the electrospun fibers decreased with increasing the polymer solution concentration. Furthermore, an optimum electrospinning voltage at which maximum degree of crystallinity can be obtained was observed. At voltages higher or lower than the optimum electrospinning voltage, the degree of crystallinity will decrease or increase, respectively. The effect of the needle tip to collector distance (NTCD on the degree of crystallinity follows no predictable and consistent pattern.

  15. On the determination of crystallinity and cellulose content in plant fibres

    DEFF Research Database (Denmark)

    Thygesen, Anders; Oddershede, Jette; Lilholt, Hans;

    2005-01-01

    A comparative study of cellulose crystallinity based on the sample crystallinity and the cellulose content in plant fibres was performed for samples of different origin. Strong acid hydrolysis was found superior to agricultural fibre analysis and comprehensive plant fibre analysis for a consistent......-based fibres and 60 - 70 g/ 100 g cellulose in wood based fibres. These findings are significant in relation to strong fibre composites and bio-ethanol production....

  16. Catastrophic rupture of lunar rocks - A Monte Carlo simulation

    Science.gov (United States)

    Hoerz, F.; Schneider, E.; Gault, D. E.; Hartung, J. B.; Brownlee, D. E.

    1975-01-01

    A computer model based on Monte Carlo techniques was developed to simulate the destruction of lunar rocks by 'catastrophic rupture' due to meteoroid impact. Energies necessary to accomplish catastrophic rupture were derived from laboratory experiments. A crater-production rate derived from lunar rocks was utilized to calculate absolute time scales. Calculated median survival times for crystalline lunar rocks are 1.9, 4.6, 10.3, and 22 m.y. for rock masses of 10, 100, 1000, and 10,000 g, respectively. Corresponding times of 6, 14.5, 32, and 68 million years are required before the probability of destruction reaches 0.99. These results are consistent with absolute exposure ages measured on returned rocks. Some results also substantiate previous conclusions that the catastrophic-rupture process is significantly more effective in obliterating lunar rocks than mass wasting by single-particle abrasion. The view is also corroborated that most rocks presently on the lunar surface either are exhumed from the regolith or are fragments of much larger boulders rather than primary ejecta excavated from pristine bedrock.

  17. Characteristics of the crystalline basement beneath the Ordos Basin:Constraint from aeromagnetic data

    Institute of Scientific and Technical Information of China (English)

    Zhentao Wang; Hongrui Zhou; Xunlian Wang; Xiuchun Jing

    2015-01-01

    Aeromagnetic anomaly zonation of the Ordos Basin and adjacent areas was obtained by processing high-precision and large-scale aeromagnetic anomalies with an approach of reduction to the pole upward continuation. Comparative study on aeromagnetic and seismic tomography suggests that aeromagnetic anomalies in this area are influenced by both the magnetic property of the rock and the burial depth of the Precambrian crystalline basement. Basement depth might be the fundamental control factor for aeromagnetic anomalies because the positive and negative anomalies on the reduction to the pole-upward-continuation anomaly maps roughly coincide with the uplifts and depressions of the crystal-line basement in the basin. The results, together with the latest understanding of basement faults, SHRIMP U-Pb zircon dating of metamorphic rock and granite, drilling data, detrital zircon ages, and gravity data interpretation, suggest that the Ordos block is not an entirety of Archean.

  18. Space Weathering of Rocks

    Science.gov (United States)

    Noble, Sarah

    2011-01-01

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

  19. Crystalline color superconductors: A review

    CERN Document Server

    Anglani, Roberto; Ciminale, Marco; Gatto, Raoul; Ippolito, Nicola; Mannarelli, Massimo; Ruggieri, Marco

    2013-01-01

    Non-homogenous superconductors and non-homogenous superfluids appear in a variety of contexts which include quark matter at extreme densities, fermionic systems of cold atoms, type-II cuprates and organic superconductors. In the present review we shall focus on the properties of quark matter at high baryonic density which can exist in the interior of compact stars. The conditions that are realized in this stellar objects tend to disfavor standard symmetric BCS pairing and may be in favor of a non-homogenous color superconducting phase. We discuss in details the properties of non-homogenous color superconductors and in particular of crystalline color superconductors. We also review the possible astrophysical signatures associated with the presence of non-homogenous color superconducting phases within the core of compact stars.

  20. 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.

  1. Effect of the crystallinity on the leaching of thorium dioxide

    International Nuclear Information System (INIS)

    The effect of the precursor and temperature of calcination on the crystallinity and the dissolution of thorium dioxide has been studied. For a calcination temperature of 900 deg. C, the largest crystallite is obtained from the precipitation of thorium oxalate. The dissolution of crystallized ThO2 has been studied as a function of pH. High temperature crystallized ThO2 is less soluble by two order of magnitude than hydrous ThO2. We have pointed out a correlation between the crystallinity of the solid and its apparent leachability in acidic perchlorate solutions, resulting mainly in the thorium site concentration differences between solids. However, the normalized dissolution rate of crystallized ThO2 is independent on the way of synthesis of the solid. (authors)

  2. Determination of chlorine in silicate rocks

    Science.gov (United States)

    Peck, L.C.

    1959-01-01

    In a rapid accurate method for the determination of chlorine in silicate rocks, the rock powder is sintered with a sodium carbonate flux containing zinc oxide and magnesium carbonate. The sinter cake is leached with water, the resulting solution is filtered, and the filtrate is acidified with nitric acid. Chlorine is determined by titrating this solution with mercuric nitrate solution using sodium nitroprusside as the indicator. The titration is made in the dark with a beam of light shining through the solution. The end point of the titration is found by visually comparing the intensity of this beam of light with that of a similar beam of light in a reference solution.

  3. Preliminary environmental assessments of disposal of rock mined during excavation of a federal repository for radioactive waste

    International Nuclear Information System (INIS)

    Since the environmental impact of mined rock handling will be dependent not only upon the nature of the material and the way in which it might be disposed but also upon the features of the disposal site area and surroundings, it was necessary to select ''reference environmental locii'' within the regions of geological interest to typify the environmental setting into which the rock would be placed. Reference locii (locations) were developed for consideration of the environmental implications of mined rock from: bedded rock salt from the Salina region, bedded rock salt from the Permian region, dome rock salt from the Gulf Interior region, Pierre shale from the Argillaceous region, granite from the crystalline rock region, volcanic basalt rock from the crystalline ash region, and carbonate rock from the limestone region. Each of these reference locii was examined with respect to those demographic, geographic, physical and ecological attributes which might be impacted by various mined rock disposal alternatives. Alternatives considered included: onsite surface storage, industrial or commercial use, offsite disposal, and environmental blending. Potential impact assessment consists of a qualitative look at the environmental implications of various alternatives for handling the mined rock, given baseline characteristics of an area typified by those represented by the ''reference locus''

  4. 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"

  5. 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

  6. Preliminary Study on weathering and pedogenesis of carbonate rock

    Institute of Scientific and Technical Information of China (English)

    王世杰; 季宏兵; 欧阳自远; 周德全; 郑乐平; 黎廷宇

    1999-01-01

    South China is the largest continuous distribution area of carbonate rock in the world. The origin of the soils over the bedrock carbonate rock has long been a controversial topic. Here further exploration is made by taking five soil profiles as examples, which are developed over the bedrock dolomitite and limestone and morphologically located in upland in karst terrain in the central, west and north Guizhou as well as west Hunan, and proved to be the weathering profiles of carbonate rock by the research results of acid-dissolved extraction experiment of bedrock, mineralogy and trace element geochemistry. Field, mineralogical and trace element geochemical characteristics of weathering and pedogenesis for carbonate rock are discussed in detail. It is pointed out that weathering and pedogenesis of carbonate rock are important pedogenetic mechanisms for soil resources in karst area, providing a basis for further researches on the origin of soils widely overlying bedrock carbonate rocks in South China.

  7. Origin and significance of tourmalinites and tourmaline-bearing rocks of Menderes Massif, western Anatolia, Turkey

    OpenAIRE

    Yucel-ozturk, Yesim; HELVACI, Cahit; Palmer, Martin R.; Ersoy, E. Yalcin; Freslon, Nicolas

    2015-01-01

    In the western central portion of Anatolia lies the Menderes Massif – a large metamorphic crystalline complex made of Neoproterozoic to Precambrian basement rocks overlain by Palaeozoic to early Tertiary metasedimentary rocks, and with a multistage metamorphic evolution developed from the late Neo-Proterozoic to Eocene. We have undertaken a study of the petrology, geochemistry and boron isotope composition of these tourmaline occurrences aiming to constrain the processes responsible for the e...

  8. Aldehyde dehydrogenase-derived omega-crystallins of squid and octopus. Specialization for lens expression.

    Science.gov (United States)

    Zinovieva, R D; Tomarev, S I; Piatigorsky, J

    1993-05-25

    omega-Crystallin of the octopus lens is related to aldehyde dehydrogenases (ALDH) of vertebrates (Tomarev, S. I., Zinovieva, R. D., and Piatigorsky, J. (1991) J. Biol. Chem. 266, 24226-24231) and ALDH1/eta-crystallin of elephant shrews (Wistow, G., and Kim, H. (1991) J. Mol. Evol. 32, 262-269). Only very low amounts of omega-crystallin are present in the squid lens. Here, we have cloned omega-crystallin cDNAs of the octopus (Octopus dofleini) and squid (Ommastrephes sloani pacificus) lenses. The deduced amino acid sequences of omega-crystallin from these species are 78% identical to each other, 56-58% identical to cytoplasmic ALDH1 and mitochondrial ALDH2 of vertebrates (which are 66-68% identical to each other), and 40% identical to Escherichia coli and spinach ALDHs. These data are consistent with the idea that the ALDH1/ALDH2 gene duplication in vertebrates occurred after divergence of cephalopods from the line giving rise to vertebrates, but before the separation of squid and octopus. Southern blot hybridization indicated that omega-crystallin is encoded by few genes (possibly just one) in octopus and squid. Northern blot hybridization revealed two bands (2.7 and 9.0 kilobases) of omega-crystallin RNA in the octopus lens and one band (4.2 kilobases) in the squid lens; omega-crystallin RNAs were undetectable in numerous non-lens tissues of octopus and squid, suggesting lens-specific expression of this gene(s). Finally, extracts of the octopus lens had no detectable ALDH activity using different substrates, consistent with omega-crystallin having no enzymatic activity. Taken together, our results suggest that omega-crystallin evolved by duplication of an ancestral gene encoding ALDH and subsequently specialized for refraction in the transparent lens while losing ALDH activity and expression in other tissues. PMID:7684383

  9. H-Bonded Liquid Crystalline Polymer Network Materials

    Institute of Scientific and Technical Information of China (English)

    LIN Hong-Cheu; HENDRIANTO Jemmy

    2001-01-01

    @@Side-chain copolymers, poly(mOBA-co-mStilb)s, composed of proton acceptors (stilbazoles) and proton donors (benzoic acids) connected to polyacrylate backbone with different methylene spacer lengths (m = 6 and 10) were prepared in different donor/acceptor molar ratios. The H-bonded copolymeric networks were formed once they were synthesized, and showed more homogenous phase than the physical-blended supramolecular networks consisting of donor and acceptor homopolymers, i.e.H-bonded blends of PmOBA and PmStilb. In order to compare the effects of the backbone connection of these H-bonded copolymers and blends, we also built monomer-monomer and polymer-monomer H-bonded complexes of similar structures (shown in Fig. 1). DSC, POM, and powder XRD studies reveal that the copolymers (m = 10)with mole fractions of benzoic acids between 0.33-0.83 show the smectic A (SMA) phase with layer spacing values between 42.22A-50.47A (increases with higher H-bonded crosslinking density between benzoic acids and stilbazoles), while for m = 6, liquid crystalline behavior still can be observed at 0.89 molar fraction of benzoic acids. However, on the basis of powder XRD study it is found that the d spacing values of H-bonded copolymers with m = 6 in the SmA phase increase with higher molar ratios of benzoic acids, which is agreed with the formation of microphase separation due to the hydrogen bonds of benzoic acids connected themselves from the same backbone. The isotropization temperatures of the H-bonded copolymers and blends increase as the molar ratios of benzoic acids increase, while the higher crosslinking density of the H-bonded copolymeric networks and blends can stabilize the liquid crystalline phase.

  10. H-Bonded Liquid Crystalline Polymer Network Materials

    Institute of Scientific and Technical Information of China (English)

    LIN; Hong-Cheu

    2001-01-01

    Side-chain copolymers, poly(mOBA-co-mStilb)s, composed of proton acceptors (stilbazoles) and proton donors (benzoic acids) connected to polyacrylate backbone with different methylene spacer lengths (m = 6 and 10) were prepared in different donor/acceptor molar ratios. The H-bonded copolymeric networks were formed once they were synthesized, and showed more homogenous phase than the physical-blended supramolecular networks consisting of donor and acceptor homopolymers, i.e.H-bonded blends of PmOBA and PmStilb. In order to compare the effects of the backbone connection of these H-bonded copolymers and blends, we also built monomer-monomer and polymer-monomer H-bonded complexes of similar structures (shown in Fig. 1). DSC, POM, and powder XRD studies reveal that the copolymers (m = 10)with mole fractions of benzoic acids between 0.33-0.83 show the smectic A (SMA) phase with layer spacing values between 42.22A-50.47A (increases with higher H-bonded crosslinking density between benzoic acids and stilbazoles), while for m = 6, liquid crystalline behavior still can be observed at 0.89 molar fraction of benzoic acids. However, on the basis of powder XRD study it is found that the d spacing values of H-bonded copolymers with m = 6 in the SmA phase increase with higher molar ratios of benzoic acids, which is agreed with the formation of microphase separation due to the hydrogen bonds of benzoic acids connected themselves from the same backbone. The isotropization temperatures of the H-bonded copolymers and blends increase as the molar ratios of benzoic acids increase, while the higher crosslinking density of the H-bonded copolymeric networks and blends can stabilize the liquid crystalline phase.……

  11. Utilization Effects of Crystalline Amino Acids and Requirement of Lysine for Juvenile Yellowcheek Carp (Elopichthys bambusa)%鱤幼鱼对晶体氨基酸的利用效果及赖氨酸需求量的研究

    Institute of Scientific and Technical Information of China (English)

    杨威; 樊启学; 宗克金; 宋林; 张云龙; 彭聪; 胡培培

    2012-01-01

    An 8-week feeding trial was conducted to evaluate the utilization effects of crystalline amino acids for juvenile yellowcheek carp (Elopichthys bambusa) , and to determine the dietary lysine requirement. Seven isonitrogenous diets were formulated. The diet which had conjugated proteins (fish meal and casein) as the only protein source was control group diet. In the diets of experimental groups, crystalline amino acids were used to replace part of casein on the basis of the control group diet, and different levels of L-lysine ,HC1 were supplemented into the above diets to achieve lysine levels from 1.9% to 4. 5% with a 0. 5% increment. A total of 378 juvenile yellowcheek carp with initial body weight of (2. 36 ±0. 08) g were randomly divided into 7 groups with 3 replicates per group and 18 fish per replicate, and each group were randomly fed one of the 7 experimental diets. The results showed as follows; although growth performance appeared different degrees of decline when part of casein replaced by crystalline amino acids, the special gain rate of 3. 46% and 3. 94% groups had no significant difference compared with the control group (P 0. 05). The weight gain rate, special gain rate, apparent digestibility of dry matter and protein, hepatopancreas lipase activity, serum protein and cholesterol contents, and serum alkaline phosphatase activity of juvenile yellowcheek carp had a trend first increased and then decreased with increasing dietary lysine level. It is concluded that crystalline amino acids can be used by juvenile yellowcheek carp, and the utilization effects are related to the balance of amino acid composition. Using weight gain rate as index, quadratic curve model indicate that the optimal dietary lysine requirement for juvenile yellowcheek carp is 3. 40% (DM basis) when dietary crude protein content is 46% (DM basis).%本试验旨在探讨鱤幼鱼对晶体氨基酸的利用效果,并在此基础上确定鱤幼鱼赖氨酸的需求量.试验设计7组

  12. Heavy ion irradiation of crystalline water ice

    CERN Document Server

    Dartois, E; Boduch, P; Brunetto, R; Chabot, M; Domaracka, A; Ding, J J; Kamalou, O; Lv, X Y; Rothard, H; da Silveira, E F; Thomas, J C

    2015-01-01

    Under cosmic irradiation, the interstellar water ice mantles evolve towards a compact amorphous state. Crystalline ice amorphisation was previously monitored mainly in the keV to hundreds of keV ion energies. We experimentally investigate heavy ion irradiation amorphisation of crystalline ice, at high energies closer to true cosmic rays, and explore the water-ice sputtering yield. We irradiated thin crystalline ice films with MeV to GeV swift ion beams, produced at the GANIL accelerator. The ice infrared spectral evolution as a function of fluence is monitored with in-situ infrared spectroscopy (induced amorphisation of the initial crystalline state into a compact amorphous phase). The crystalline ice amorphisation cross-section is measured in the high electronic stopping-power range for different temperatures. At large fluence, the ice sputtering is measured on the infrared spectra, and the fitted sputtering-yield dependence, combined with previous measurements, is quadratic over three decades of electronic ...

  13. Crystallinity and thermal resistance of microcrystalline cellulose prepared from manau rattan (Calamusmanan)

    Science.gov (United States)

    Rizkiansyah, Raden Reza; Mardiyati, Steven, Suratman, R.

    2016-04-01

    The objective of this study was to prepare microcrystalline cellulose from Manau rattan (Calamusmanan) and to investigate the influence of concentration of sulfuric acid and hydrolysis time on crystallinity and thermal resistance of the microcrystalline cellulose (MCC). In this research, MCC was extracted through two stages, which is alkalization and acid hydrolysis. Alkalization was prepared by soaking manau rattan powder into sodium hydroxide (NaOH) 17.5wt% at 100°C for 8 hours. Acid hydrolysis was prepared by using sulfuric acid with concentration 0.1 M; 0.3 M; and 0.5 M for 4, 6, 8 and 10 hours. Crystallinity of MCC was measured by XRD, and thermal resistance was characterized by TGA. MCC was successfully extracted from manau rattan. The highest crystallinity of MCC obtained was 72.42% which prepared by acid hydrolysis with concentration 0.5 M for 10 hours. MCC prepared by acid hydrolysis with concentration 0.5 M for 10 hours not only resulted the highest crystallinity but also the best thermal resistance.

  14. Diffusion of water, cesium and neptunium in pores of rocks

    International Nuclear Information System (INIS)

    Teollisuuden Voima Oy (TVO) is investigating the feasibility to dispose of spent nuclear fuel within Finland. The present plan calls for the repository to be located in crystalline rock at a depth of several hundred meters. The safety assessment of the repository includes calculations of migration of waste nuclides. The flow of waste elements in groundwater will be retarded through sorption interaction with minerals and through diffusion into rock. Diffusion is the only mechanism retarding the migration of non-sorbing species and, it is expected to be the dominating retardation mechanism of many of the sorbing elements. In the investigation the simultaneous diffusion of tritiated water (HTO), cesium and neptunium in rocks of TVO investigation sites at Kivetty, Olkiluoto and Romuvaara were studied. (11 refs., 33 figs., 9 tabs.)

  15. Leaching of boron, arsenic and selenium from sedimentary rocks: II. pH dependence, speciation and mechanisms of release

    Energy Technology Data Exchange (ETDEWEB)

    Tabelin, Carlito Baltazar, E-mail: carlito@trans-er.eng.hokudai.ac.jp [Laboratory of Soil Environment Engineering, Faculty of Engineering, Hokkaido University, Sapporo (Japan); Hashimoto, Ayaka, E-mail: a.hashimoto@diaconsult.co.jp [DIA Consultants Co. Ltd., Sapporo (Japan); Igarashi, Toshifumi, E-mail: tosifumi@eng.hokudai.ac.jp [Laboratory of Groundwater and Mass Transport, Faculty of Engineering, Hokkaido University, Sapporo (Japan); Yoneda, Tetsuro, E-mail: yonet@eng.hokudai.ac.jp [Laboratory of Soil Environment Engineering, Faculty of Engineering, Hokkaido University, Sapporo (Japan)

    2014-03-01

    Sedimentary rocks excavated in Japan from road- and railway-tunnel projects contain relatively low concentrations of hazardous trace elements like boron (B), arsenic (As) and selenium (Se). However, these seemingly harmless waste rocks often produced leachates with concentrations of hazardous trace elements that exceeded the environmental standards. In this study, the leaching behaviors and release mechanisms of B, As and Se were evaluated using batch leaching experiments, sequential extraction and geochemical modeling calculations. The results showed that B was mostly partitioned with the residual/crystalline phase that is relatively stable under normal environmental conditions. In contrast, the majority of As and Se were associated with the exchangeable and organics/sulfides phases that are unstable under oxidizing conditions. Dissolution of water-soluble phases controlled the leaching of B, As and Se from these rocks in the short term, but pyrite oxidation, calcite dissolution and adsorption/desorption reactions became more important in the long term. The mobilities of these trace elements were also strongly influenced by the pH of the rock-water system. Although the leaching of Se only increased in the acidic region, those of B and As were enhanced under both acidic and alkaline conditions. Under strongly acidic conditions, the primarily release mechanism of B, As and Se was the dissolution of mineral phases that incorporated and/or adsorbed these elements. Lower concentrations of these trace elements in the circumneutral pH range could be attributed to their strong adsorption onto minerals like Al-/Fe-oxyhydroxides and clays, which are inherently present and/or precipitated in the rock-water system. The leaching of As and B increased under strongly alkaline conditions because of enhanced desorption and pyrite oxidation while that of Se remained minimal due to its adsorption onto Fe-oxyhydroxides and co-precipitation with calcite. - Highlights: • The bulk of

  16. Region-to-area screening methodology for the crystalline repository project

    International Nuclear Information System (INIS)

    The ''Nuclear Waste Policy Act of 1982'' (NWPA), enacted January 7, 1983 as Public Law 97-425, confirmed the responsibility of the US Department of Energy (DOE) for management of high-level radioactive waste. The NWPA directed the DOE to provide safe facilities for isolation of high-level radioactive waste from the environment in federally owned and federally licensed repositories. To achieve the goals of providing licensed repositories for high-level radioactive waste, a technical program has been developed by the DOE to meet all relevant radiological protection criteria and other requirements. By March 1987, the NWPA requires the DOE to recommend to the President a single site, chosen from five nominated sites for construction of the first repository. Rock types being considered as potential hosts for the first repository include salt, basalt, and tuff. The NWPA also requires the DOE to select three candidate sites, chosen from five nominated sites to be recommended to the President by July 1989, as possible locations for the second repository. Potential host rock types for the second federal repository will include crystalline rock. This document outlines the methodology for region-to-area screening of exposed crystalline rock bodies for suitability as sites for further study. 17 refs., 14 figs., 2 tabs

  17. Rock mechanics research awards

    Science.gov (United States)

    Wagner, John E.

    The U.S. National Committee for Rock Mechanics, at its June 1983 annual meeting, adopted three actions to enhance the competition and public awareness of its annual awards program for rock mechanics papers. It will issue a call for nominations of outstanding papers; it will request participating societies to announce the names of award winners and the titles of papers, and it will publish an abstract of the winning papers in the proceedings of the annual U.S. Rock Mechanics Symposium in the year following the awards.The competition is open to papers, by U.S residents or students in a U.S. school, published in an English language publication normally available in the United States. The following authors and papers are the 1983 award winners:

  18. ELECTROCHROMETIC STUDIES ON POLAR MULTILAYERS OF LIQUID CRYSTALLINE POLYMERS

    Institute of Scientific and Technical Information of China (English)

    GONG Mingxuan; REN Yanzhi; LIU Wang; GAO Manglai; ZHAO Yingying; BAI Yubai; LI Tiejin

    1995-01-01

    Electrochrometic measurements were carried on the Z-type Langmuir-Blodgett films oftwo liquid crystalline polymers: mono- {6-[4-(phenylazo) naphthyloxy] hexyl } (1a) andmono- { 6-[4- (anthraquinone-1-azo) naphthyloxy] hexyl} (2a) ester of polymaleic acid . Itwas found that for both polymers, poling fields parallel and antiparallel to dipole momentsof the polymer side chains induce red and blue shift in absorption bands, respectively. Forpolymer la blue shift is accompanied by absorbance increase, while red shift by absorbancedecrease;but for polymer 2a only decrease in absorbance is observed. A simple model wasproposed to analyze the results.

  19. Digital carbonate rock physics

    Science.gov (United States)

    Saenger, Erik H.; Vialle, Stephanie; Lebedev, Maxim; Uribe, David; Osorno, Maria; Duda, Mandy; Steeb, Holger

    2016-08-01

    Modern estimation of rock properties combines imaging with advanced numerical simulations, an approach known as digital rock physics (DRP). In this paper we suggest a specific segmentation procedure of X-ray micro-computed tomography data with two different resolutions in the µm range for two sets of carbonate rock samples. These carbonates were already characterized in detail in a previous laboratory study which we complement with nanoindentation experiments (for local elastic properties). In a first step a non-local mean filter is applied to the raw image data. We then apply different thresholds to identify pores and solid phases. Because of a non-neglectable amount of unresolved microporosity (micritic phase) we also define intermediate threshold values for distinct phases. Based on this segmentation we determine porosity-dependent values for effective P- and S-wave velocities as well as for the intrinsic permeability. For effective velocities we confirm an observed two-phase trend reported in another study using a different carbonate data set. As an upscaling approach we use this two-phase trend as an effective medium approach to estimate the porosity-dependent elastic properties of the micritic phase for the low-resolution images. The porosity measured in the laboratory is then used to predict the effective rock properties from the observed trends for a comparison with experimental data. The two-phase trend can be regarded as an upper bound for elastic properties; the use of the two-phase trend for low-resolution images led to a good estimate for a lower bound of effective elastic properties. Anisotropy is observed for some of the considered subvolumes, but seems to be insignificant for the analysed rocks at the DRP scale. Because of the complexity of carbonates we suggest using DRP as a complementary tool for rock characterization in addition to classical experimental methods.

  20. Synthesis and Characterization of ZSM-5/β Co-Crystalline Zeolite

    Institute of Scientific and Technical Information of China (English)

    Tianbo Zhao; Huiying Zhang; Fengyan Li; Chao Yang; Baoning Zong

    2005-01-01

    ZSM-5/β co-crystalline zeolites with different content of ZSM-5 have been synthesized by adding different amount of ZSM-5 to the synthetic system ofβ zeolite with NaAlO2, silica sol as the source of aluminum and silica, respectively, and TEA+ as the template under controlled condition of the synthesis. The ZSM-5/β co-crystalline zeolite was studied by XRD, SEM, BET and NH3-TPD. The reaction activity of toluene alkylation was investigated with a mixture of toluene-methanol as the feedstock in a pulse micro-reactor over the ZSM-5/β co-crystalline zeolite. It is found that ZSM-5/β co-crystalline zeolite has two kinds of zeolite structure including ZSM-5 and β zeolite, not in the form of a physical mixture. The pore structure of ZSM-5/β co-crystalline zeolites is different from that forβ zeolite, ZSM-5and their physical mixture. In addition, the peaks of both high and low temperature desorption of ammonia over the ZSM-5/β co-crystalline zeolite shift 23 ℃ to lower temperatures and the acid amount of its strong acid is 3% more than the physical mixture. So the ZSM-5/β co-crystalline zeolite produces the highest content of xylene, which is 10.4% higher than the physical mixture. And the ZSM-5/β co-crystalline zeolite has better selectivity for toluene alkylation and weaker de-methylation than β zeolite, ZSM-5 and their physical mixture.

  1. Rock engineering applications, 1991

    International Nuclear Information System (INIS)

    This book demonstrates how to apply the theories and principles of rock engineering to actual engineering and construction tasks. It features insights on geology for mining and tunnelling applications. It is practical resource that focuses on the latest technological innovation and examines up-to-date procedures used by engineers for coping with complex rock conditions. The authors also discuss question related to underground space, from design approaches to underground housing and storage. And they cover the monitoring of storage caverns for liquid and gaseous products or toxic and radioactive wastes

  2. Rock Hellsinki, Marketing Research

    OpenAIRE

    Todd, Roosa; Jalkanen, Katariina

    2013-01-01

    This paper is a qualitative research about rock and heavy metal music tourism in the capital city of Finland, Helsinki. As Helsinki can be considered the city of contrasts, the silent nature city mixed with urban activities, it is important to also use the potential of the loud rock and heavy metal music contrasting the silence. Finland is known abroad for bands such as HIM, Nightwish, Korpiklaani and Children of Bodom so it would make sense to utilize these in the tourism sector as well. The...

  3. Session: Hard Rock Penetration

    Energy Technology Data Exchange (ETDEWEB)

    Tennyson, George P. Jr.; Dunn, James C.; Drumheller, Douglas S.; Glowka, David A.; Lysne, Peter

    1992-01-01

    This session at the Geothermal Energy Program Review X: Geothermal Energy and the Utility Market consisted of five presentations: ''Hard Rock Penetration - Summary'' by George P. Tennyson, Jr.; ''Overview - Hard Rock Penetration'' by James C. Dunn; ''An Overview of Acoustic Telemetry'' by Douglas S. Drumheller; ''Lost Circulation Technology Development Status'' by David A. Glowka; ''Downhole Memory-Logging Tools'' by Peter Lysne.

  4. Area Recommendation Report for the Crystalline Repository Project: Volume 1, Draft

    International Nuclear Information System (INIS)

    This Draft Area Recommendation Report for the Crystalline Repository Project identifies portions of crystalline rock bodies as proposed potentially acceptable sites for consideration in the second high-level radioactive waste repository program. The US Department of Energy evaluated available geologic and environmental data for 235 crystalline rock bodies in the North Central, Northeastern, and Southeastern regions to identify preliminary candidate areas. Further evaluation of these preliminary candidate areas resulted in the selection of 12 as proposed potentially acceptable sites. The 12 proposed potentially acceptable sites are located in the States of Georgia (1), Maine (2), Minnesota (3), New Hampshire (1), North Carolina (2), Virginia (2), and Wisconsin (1). The data, analyses, and rationale with which the 12 proposed potentially acceptable sites were selected are presented in this draft report. The analyses presented demonstrate that the evidence available for each proposed potentially acceptable site supports (1) a finding that the site is not disqualified in accordance with the application requirements of Appendix III of the siting guidelines and (2) a decision to proceed with the continued investigation of the site on the basis of the favorable and potentially adverse conditions identified to date. Once this report is finalized, potentially acceptable sites in crystalline rock will be formally identified by the Secretary of Energy, in accordance with the DOE siting guidelines. These potentially acceptable sites will be investigated and evaluated in more detail during the area phase of the siting process. An additional eight areas, which meet the requirements for identification as potentially acceptable sites, will retain their designation as candidate areas

  5. Site investigations: Strategy for rock mechanics site descriptive model

    International Nuclear Information System (INIS)

    As a part of the planning work for the Site Investigations, SKB has developed a Rock Mechanics Site Descriptive Modelling Strategy. Similar strategies are being developed for other disciplines. The objective of the strategy is that it should guide the practical implementation of evaluating site specific data during the Site Investigations. It is also understood that further development may be needed. This methodology enables the crystalline rock mass to be characterised in terms of the quality at different sites, for considering rock engineering constructability, and for providing the input to numerical models and performance assessment calculations. The model describes the initial stresses and the distribution of deformation and strength properties of the intact rock, of fractures and fracture zones, and of the rock mass. The rock mass mechanical properties are estimated by empirical relations and by numerical simulations. The methodology is based on estimation of mechanical properties using both empirical and heroretical/numerical approaches; and estimation of in situ rock stress using judgement and numerical modelling, including the influence of fracture zones. These approaches are initially used separately, and then combined to produce the required characterisation estimates. The methodology was evaluated with a Test Case at the Aespoe Hard Rock Laboratory in Sweden. The quality control aspects are an important feature of the methodology: these include Protocols to ensure the structure and coherence of the procedures used, regular meetings to enhance communication, feedback from internal and external reviewing, plus the recording of an audit trail of the development steps and decisions made. The strategy will be reviewed and, if required, updated as appropriate

  6. Site investigations: Strategy for rock mechanics site descriptive model

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Johan [JA Streamflow AB, Aelvsjoe (Sweden); Christiansson, Rolf [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Hudson, John [Rock Engineering Consultants, Welwyn Garden City (United Kingdom)

    2002-05-01

    As a part of the planning work for the Site Investigations, SKB has developed a Rock Mechanics Site Descriptive Modelling Strategy. Similar strategies are being developed for other disciplines. The objective of the strategy is that it should guide the practical implementation of evaluating site specific data during the Site Investigations. It is also understood that further development may be needed. This methodology enables the crystalline rock mass to be characterised in terms of the quality at different sites, for considering rock engineering constructability, and for providing the input to numerical models and performance assessment calculations. The model describes the initial stresses and the distribution of deformation and strength properties of the intact rock, of fractures and fracture zones, and of the rock mass. The rock mass mechanical properties are estimated by empirical relations and by numerical simulations. The methodology is based on estimation of mechanical properties using both empirical and heroretical/numerical approaches; and estimation of in situ rock stress using judgement and numerical modelling, including the influence of fracture zones. These approaches are initially used separately, and then combined to produce the required characterisation estimates. The methodology was evaluated with a Test Case at the Aespoe Hard Rock Laboratory in Sweden. The quality control aspects are an important feature of the methodology: these include Protocols to ensure the structure and coherence of the procedures used, regular meetings to enhance communication, feedback from internal and external reviewing, plus the recording of an audit trail of the development steps and decisions made. The strategy will be reviewed and, if required, updated as appropriate.

  7. Petrology of upper Eocene-Oligocene plutonic rocks of Moalleman Damghan area

    Science.gov (United States)

    Kohansal, Reza; Zolfaghari, Seddigheh; Hashem Emami, Mohammad

    2010-05-01

    The plutonic rocks of this area include cryptodoms, hypoabyssal plutonic bodies and dikes which intruded in to the late Lutetian- late Eocene rocks. The hypoabyssal plutonic rocks in Moalleman are classified in to two main groups: - Acidic rocks, including microgranite to microgranodiorite. - Intermediate rocks, including microquartzmonzodiorite to microquartzdiorite of hypoabyssal type. Presence of fine-grained mafic xenoliths with abundant biotite, amphibole and pyroxene in the intermediate rocks may be considered as an evidence of the role of mantle melting occurrence in the formation of these rocks. Occurrence of a felsitic texture, showing a high differentiation coefficient and existence of large quarts which are embayed, rounded and infiltered by material, and finally turmalinization in the acidic rocks due to Boron metasomatism suggest the role of crust in the formation of afore mentioned rocks as well. In some acidic rocks plagioclases show oscillatory zoning. This phenomenon along with the fact that biotite granites in these rocks crystallized before crystallization of quarts and after crystallization of alkali feldspar suggest that the crystallization of these rocks accomplished in the presence of 2 percent water, pertitic texture in some feldspars of the intermediate rocks this conclusion. Supports on the basis of the geochemical studies most of the hypoabyssal rocks of Moalleman area fall in subalkaline- calcoalkaline fields. Variation of immobile incompatible trace elements versus differentiation coefficient and the situation of samples in winkler diagram show the role of crustal- melting in the formation of acidic rocks. Trace element content of some rocks (e.g. Cu and Sm) with in this group show mantle specification, while some other rocks (e.g. Zr, Th, Hf) show crustal specification. The intermediate rocks of the study area therefore, indicate a hybridization of magmas from both the mantle and crust. Study of the temperature and water vapour

  8. Rocking and Rolling Rattlebacks

    Science.gov (United States)

    Cross, Rod

    2013-01-01

    A rattleback is a well-known physics toy that has a preferred direction of rotation. If it is spun about a vertical axis in the "wrong" direction, it will slow down, start rocking from end to end, and then spin in the opposite (i.e. preferred) direction. Many articles have been written about rattlebacks. Some are highly mathematical and…

  9. Umhlanga Rocks coastal defense

    NARCIS (Netherlands)

    De Jong, L.; De Jong, B.; Ivanova, M.; Gerritse, A.; Rietberg, D.; Dorrepaal, S.

    2014-01-01

    The eThekwini coastline is a vulnerable coastline subject to chronic erosion and damage due to sea level rise. In 2007 a severe storm caused major physical and economic damage along the coastline, proving the need for action. Umhlanga Rocks is a densely populated premium holiday destination on the e

  10. Rock solid energy solution

    International Nuclear Information System (INIS)

    Scientists believe naturally radioactive rocks below the earth's surface could provide an inexhaustible and environmentally friendly power source. And Australia could be a geological hotbed should the concept get off the ground. Despite the scale, the concept itself is simple. The Earth's reserves of heat in naturally radioactive rocks could provide an effectively inexhaustible and environmentally friendly source of power. No greenhouse gas emissions, little water usage and minimal pollution. Natural hot springs are already used to make power in some parts of the world, such as Iceland, but creating artificial hot springs by drilling deep into granite -the hardest of rocks - is a much more ambitious concept. One cubic kilometre of hot granite at 250 deg C has the stored energy equivalent of 40 million barrels of oil. In a nutshell, water is pumped into the hot zone - some 3km to 5km down in Australian conditions - and spreads through a 'reservoir' of hot, cracked rocks. Once superheated, it returns to the surface as steam through a separate production well to spin turbines and generate electricity. The water can then be recaptured and reused, with test sites around the world recovering up to around 90 per cent

  11. Rock-hard coatings

    NARCIS (Netherlands)

    Muller, M.

    2007-01-01

    Aircraft jet engines have to be able to withstand infernal conditions. Extreme heat and bitter cold tax coatings to the limit. Materials expert Dr Ir. Wim Sloof fits atoms together to develop rock-hard coatings. The latest invention in this field is known as ceramic matrix composites. Sloof has sign

  12. Slippery Rock University

    Science.gov (United States)

    Arnhold, Robert W.

    2008-01-01

    Slippery Rock University (SRU), located in western Pennsylvania, is one of 14 state-owned institutions of higher education in Pennsylvania. The university has a rich tradition of providing professional preparation programs in special education, therapeutic recreation, physical education, and physical therapy for individuals with disabilities.…

  13. Liquid crystalline cellulose derivatives for mirrorless lasing

    OpenAIRE

    Wenzlik, Daniel

    2013-01-01

    In this thesis cholesteric films made of liquid crystalline cellulose derivatives with improved optical properties were prepared. The choice of the solvent, hydrogen bond influencing additives, the synthetic realization of a very high degree of substitution on the cellulosic polymer and the use of mechanical stirring at the upper concentration limit of the liquid crystalline range were the basis for an improved alignment of the applied cellulose tricarbamates. In combination with a tuned subs...

  14. Electrochemical synthesis of highly crystalline copper nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Kaur, Amandeep [Department of Electronics and Communication Engineering, Punjabi University, Patiala 147 002, Punjab (India); Gupta, Tanish; Kumar, Akshay [Department of Nanotechnology, SGGSW University, Fatehgarh Sahib 140406, Punjab (India); Kumar, Sanjeev [Department of Applied Sciences, PEC University of Technology, Chandigarh 160012 (India); Singh, Karamjeet [Department of Physics, Punjabi University, Patiala 147002, Punjab (India); Thakur, Anup, E-mail: dranupthakur@gmail.com [Advanced Materials Research Lab, Department of Basic and Applied Sciences, Punjabi University, Patiala 147 002, Punjab (India)

    2015-05-15

    Copper nanowires were fabricated within the pores of anodic alumina template (AAT) by template synthesis method at pH = 2.9. X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) were used to investigate the structure, morphology and composition of fabricated nanowires. These characterizations revealed that the deposited copper nanowires were highly crystalline in nature, dense and uniform. The crystalline copper nanowires are promising in application of future nanoelectronic devices and circuits.

  15. Crystalline Silicon Dielectrics for Superconducting Qubit Circuits

    Science.gov (United States)

    Hover, David; Peng, Weina; Sendelbach, Steven; Eriksson, Mark; McDermott, Robert

    2009-03-01

    Superconducting qubit energy relaxation times are limited by microwave loss induced by a continuum of two-level state (TLS) defects in the dielectric materials of the circuit. State-of-the-art phase qubit circuits employ a micron-scale Josephson junction shunted by an external capacitor. In this case, the qubit T1 time is directly proportional to the quality factor (Q) of the capacitor dielectric. The amorphous capacitor dielectrics that have been used to date display intrinsic Q of order 10^3 to 10^4. Shunt capacitors with a Q of 10^6 are required to extend qubit T1 times well into the microsecond range. Crystalline dielectric materials are an attractive candidate for qubit capacitor dielectrics, due to the extremely low density of TLS defects. However, the robust integration of crystalline dielectrics with superconducting qubit circuits remains a challenge. Here we describe a novel approach to the realization of high-Q crystalline capacitor dielectrics for superconducting qubit circuits. The capacitor dielectric is a crystalline silicon nanomembrane. We discuss characterization of crystalline silicon capacitors with low-power microwave transport measurements at millikelvin temperatures. In addition, we report progress on integrating the crystalline capacitor process with Josephson qubit fabrication.

  16. Aespoe Hard Rock Laboratory. Annual Report 2009

    Energy Technology Data Exchange (ETDEWEB)

    2010-12-15

    , experiments are performed under the conditions that are expected to prevail at repository depth. The experiments are related to the rock, its properties and in situ environmental conditions. The aim is to provide information about the long-term function of natural and repository barriers. Experiments are performed to develop and test methods and models for the description of groundwater flow, radionuclide migration, and chemical conditions at repository depth. The programme includes projects which aim to determine parameter values that are required as input to the conceptual and numerical models. A programme has been defined for tracer tests at different experimental scales, the so-called Tracer Retention Understanding Experiments (TRUE). The overall objectives of the experiments are to gain a better understanding of the processes which govern the retention of radionuclides transported in crystalline rock and to increase the credibility of models used for radionuclide transport calculations. During 2009, work has been performed in the projects: TRUE Block Scale Continuation (writing of papers to scientific journals) and TRUE-1 Continuation (complementary laboratory sorption experiments, reporting of fault rock zones characterisation project) and TRUE-1 Completion (analyses of material, with focus on the target structure, from the over-coring of two boreholes at the TRUE-1 site performed in 2007). The Long Term Sorption Diffusion Experiment complements the diffusion and sorption experiments performed in the laboratory, and is a natural extension of the TRUE-experiments. The in situ sorption diffusion experiment was ongoing for about six months and after injection of epoxy resin the over-coring was performed in May 2007. During 2009 the analyses on sample cores drilled from the fracture surface on the core stub and from the matrix rock surrounding the test section has continued. In addition, laboratory experiments have been performed on replica material. The Colloid Transport

  17. Aespoe Hard Rock Laboratory. Annual Report 2009

    International Nuclear Information System (INIS)

    performed under the conditions that are expected to prevail at repository depth. The experiments are related to the rock, its properties and in situ environmental conditions. The aim is to provide information about the long-term function of natural and repository barriers. Experiments are performed to develop and test methods and models for the description of groundwater flow, radionuclide migration, and chemical conditions at repository depth. The programme includes projects which aim to determine parameter values that are required as input to the conceptual and numerical models. A programme has been defined for tracer tests at different experimental scales, the so-called Tracer Retention Understanding Experiments (TRUE). The overall objectives of the experiments are to gain a better understanding of the processes which govern the retention of radionuclides transported in crystalline rock and to increase the credibility of models used for radionuclide transport calculations. During 2009, work has been performed in the projects: TRUE Block Scale Continuation (writing of papers to scientific journals) and TRUE-1 Continuation (complementary laboratory sorption experiments, reporting of fault rock zones characterisation project) and TRUE-1 Completion (analyses of material, with focus on the target structure, from the over-coring of two boreholes at the TRUE-1 site performed in 2007). The Long Term Sorption Diffusion Experiment complements the diffusion and sorption experiments performed in the laboratory, and is a natural extension of the TRUE-experiments. The in situ sorption diffusion experiment was ongoing for about six months and after injection of epoxy resin the over-coring was performed in May 2007. During 2009 the analyses on sample cores drilled from the fracture surface on the core stub and from the matrix rock surrounding the test section has continued. In addition, laboratory experiments have been performed on replica material. The Colloid Transport Project was

  18. Basic investigation and analysis for preferred host rocks and natural analogue study area with reference to high level radioactive waste disposal

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Jeong Ryul; Park, J. K.; Hwang, D. H.; Lee, J. H.; Yun, H. S.; Kim, D. Y.; Park, H. S.; Koo, S. B.; Cho, J. D.; Kim, K. E. [Korea Inst. of Geology, Mining and Materials, Taejon (Korea, Republic of)

    1997-12-01

    The purpose of this study is basic investigation and analysis for preferred host rocks and natural analogue study area to develope underground disposal technique of high level radioactive waste in future. The study has been done for the crystalline rocks(especially granitic rocks) with emphasis of abandoned metallic mines and uranium ore deposits, and for the geological structure study by using gravity and aeromagnetic data. 138 refs., 54 tabs., 130 figs. (author)

  19. A porous silica rock ("tripoli") in the footwall of the Jurassic Úrkút manganese deposit, Hungary: composition, and origin through carbonate dissolution

    Science.gov (United States)

    Polgari, Marta; Szabo, Zoltan; Szabo-Drubina, Magda; Hein, James R.; Yeh, Hsueh-Wen

    2005-01-01

    The mineralogical, chemical, and isotopic compositions were determined for a white tripoli from the footwall of the Jurassic Úrkút Mn-oxide ore deposit in the Bakony Mountains, Hungary. The tripoli consists of quartz and chalcedony, with SiO2 contents up to 100 wt.%; consequently, trace-element contents are very low. Oxygen isotopes and quartz crystallinity indicate a low-temperature diagenetic origin for this deposit. The tripoli was formed by dissolution of the carbonate portion of the siliceous (sponge spicules) Isztimér Limestone. Dissolution of the carbonate was promoted by inorganic and organic acids generated during diagensis and left a framework composed of diagenetic silica that preserved the original volume of the limestone layer. The relative enrichment of silica and high porosity is the result of that carbonate dissolution. The silty texture of this highly friable rock is due to the structurally weak silica framework.

  20. A porous silica rock (“tripoli”) in the footwall of the Jurassic Úrkút manganese deposit, Hungary: Composition, and origin through carbonate dissolution

    Science.gov (United States)

    Polgári, Márta; Szabó, Zoltán; Szabó-Drubina, Magda; Hein, James R.; Yeh, Hsueh-Wen

    2005-06-01

    The mineralogical, chemical, and isotopic compositions were determined for a white tripoli from the footwall of the Jurassic Úrkút Mn-oxide ore deposit in the Bakony Mountains, Hungary. The tripoli consists of quartz and chalcedony, with SiO 2 contents up to 100 wt.%; consequently, trace-element contents are very low. Oxygen isotopes and quartz crystallinity indicate a low-temperature diagenetic origin for this deposit. The tripoli was formed by dissolution of the carbonate portion of the siliceous (sponge spicules) Isztimér Limestone. Dissolution of the carbonate was promoted by inorganic and organic acids generated during diagensis and left a framework composed of diagenetic silica that preserved the original volume of the limestone layer. The relative enrichment of silica and high porosity is the result of that carbonate dissolution. The silty texture of this highly friable rock is due to the structurally weak silica framework.

  1. Investigation of fracture permeability around an underground opening in metamorphic rocks

    International Nuclear Information System (INIS)

    This report is the fifth in a series describing experiments conducted by the Colorado School of Mines for the Office of Crystalline Repository Development (OCRD) to determine the extent of blast damage in rock surrounding an underground opening. The report describes the instrumentation and method for testing permeability in crystalline rock masses. We applied the instruments in the CSM/OCRD test room in the Colorado School of Mines Experimental Mine (Edgar Mine) in Idaho Springs, Colorado. Even though this mine will not be a repository site, the equipment and methodology developed in this research program is applicable to other sites. The results presented in this report consider the variation of permeability measured with injection techniques. Preliminary results of core logging and deterministic fracture mapping program are briefly discussed. An attempt has also been made to relate the permeability variations to the stress field modification due to removal of the supporting rock mass

  2. Region-to-area screening methodology for the Crystalline Repository Project

    International Nuclear Information System (INIS)

    The purpose of this document is to describe the Crystalline Repository Project's (CRP) process for region-to-area screening of exposed and near-surface crystalline rock bodies in the three regions of the conterminous United States where crystalline rock is being evaluated as a potential host for the second nuclear waste repository (i.e., in the North Central, Northeastern, and Southeastern Regions). This document indicates how the US Department of Energy's (DOE) General Guidelines for the Recommendation of Sites for Nuclear Waste Repositories (10 CFR 960) were used to select and apply factors and variables for the region-to-area screening, explains how these factors and variable are to be applied in the region-to-area screening, and indicates how this methodology relates to the decision process leading to the selection of candidate areas. A brief general discussion of the screening process from the national survey through area screening and site recommendation is presented. This discussion sets the scene for detailed discussions which follow concerning the region-to-area screening process, the guidance provided by the DOE Siting Guidelines for establishing disqualifying factors and variables for screening, and application of the disqualifying factors and variables in the screening process. This document is complementary to the regional geologic and environmental characterization reports to be issued in the summer of 1985 as final documents. These reports will contain the geologic and environmental data base that will be used in conjunction with the methodology to conduct region-to-area screening

  3. Stability and cytotoxicity of crystallin amyloid nanofibrils

    Science.gov (United States)

    Kaur, Manmeet; Healy, Jackie; Vasudevamurthy, Madhusudan; Lassé, Moritz; Puskar, Ljiljana; Tobin, Mark J.; Valery, Celine; Gerrard, Juliet A.; Sasso, Luigi

    2014-10-01

    Previous work has identified crystallin proteins extracted from fish eye lenses as a cheap and readily available source for the self-assembly of amyloid nanofibrils. However, before exploring potential applications, the biophysical aspects and safety of this bionanomaterial need to be assessed so as to ensure that it can be effectively and safely used. In this study, crude crystallin amyloid fibrils are shown to be stable across a wide pH range, in a number of industrially relevant solvents, at both low and high temperatures, and in the presence of proteases. Crystallin nanofibrils were compared to well characterised insulin and whey protein fibrils using Thioflavin T assays and TEM imaging. Cell cytotoxicity assays suggest no adverse impact of both mature and fragmented crystallin fibrils on cell viability of Hec-1a endometrial cells. An IR microspectroscopy study supports long-term structural integrity of crystallin nanofibrils.Previous work has identified crystallin proteins extracted from fish eye lenses as a cheap and readily available source for the self-assembly of amyloid nanofibrils. However, before exploring potential applications, the biophysical aspects and safety of this bionanomaterial need to be assessed so as to ensure that it can be effectively and safely used. In this study, crude crystallin amyloid fibrils are shown to be stable across a wide pH range, in a number of industrially relevant solvents, at both low and high temperatures, and in the presence of proteases. Crystallin nanofibrils were compared to well characterised insulin and whey protein fibrils using Thioflavin T assays and TEM imaging. Cell cytotoxicity assays suggest no adverse impact of both mature and fragmented crystallin fibrils on cell viability of Hec-1a endometrial cells. An IR microspectroscopy study supports long-term structural integrity of crystallin nanofibrils. Electronic supplementary information (ESI) available: ThT fluorescence graphs of buffers and solvents used for

  4. Columnar liquid-crystalline dinaphthoperylenetetracarboxdiimides.

    Science.gov (United States)

    Ferreira, Marli; Girotto, Edivandro; Bentaleb, Ahmed; Hillard, Elizabeth A; Gallardo, Hugo; Durola, Fabien; Bock, Harald

    2015-03-01

    Although the double Friedel-Crafts acylation of arenes with ethyl chloroglyoxylate is hindered by the strongly deactivating effect of the first-entering glyoxylic substituent, the double reaction is successful with the reactive arene perylene under long reaction times and with concomitant ester hydrolysis. The reaction is regiospecific, giving the 3,9-regioisomer exclusively. This perylenylenediglyoxylic acid is condensed first with o-bromophenylacetic acid and then with α-branched alkylamines to yield the title compounds. Whilst the corresponding tetraalkyl esters only show monotropic mesophases, these diimides show enantiotropic columnar mesophases that can be maintained at room temperature if racemically branched alkyl chains of moderate size are used. A palladium-induced C-C bond migration during the build-up of the arene system leads to an isomeric side product of reduced symmetry that can be isolated by aggregation-controlled chromatographic separation. The HOMO and LUMO energies of the title compounds are considerably higher than those of established perylenetetracarboxdiimides. PMID:25656752

  5. Multifractal model of magnetic susceptibility distributions in some igneous rocks

    Directory of Open Access Journals (Sweden)

    M. E. Gettings

    2012-11-01

    Full Text Available Measurements of in-situ magnetic susceptibility were compiled from mainly Precambrian crystalline basement rocks beneath the Colorado Plateau and ranges in Arizona, Colorado, and New Mexico. The susceptibility meter used measures about 30 cm3 of rock and measures variations in the modal distribution of magnetic minerals that form a minor component volumetrically in these coarsely crystalline granitic to granodioritic rocks. Recent measurements include 50–150 measurements on each outcrop, and show that the distribution of magnetic susceptibilities is highly variable, multimodal and strongly non-Gaussian. Although the distribution of magnetic susceptibility is well known to be multifractal, the small number of data points at an outcrop precludes calculation of the multifractal spectrum by conventional methods. Instead, a brute force approach was adopted using multiplicative cascade models to fit the outcrop scale variability of magnetic minerals. Model segment proportion and length parameters resulted in 26 676 models to span parameter space. Distributions at each outcrop were normalized to unity magnetic susceptibility and added to compare all data for a rock body accounting for variations in petrology and alteration. Once the best-fitting model was found, the equation relating the segment proportion and length parameters was solved numerically to yield the multifractal spectrum estimate. For the best fits, the relative density (the proportion divided by the segment length of one segment tends to be dominant and the other two densities are smaller and nearly equal. No other consistent relationships between the best fit parameters were identified. The multifractal spectrum estimates appear to distinguish between metamorphic gneiss sites and sites on plutons, even if the plutons have been metamorphosed. In particular, rocks that have undergone multiple tectonic events tend to have a larger range of scaling exponents.

  6. Joint Commission on rock properties

    Science.gov (United States)

    A joint commission on Rock Properties for Petroleum Engineers (RPPE) has been established by the International Society of Rock Mechanics and the Society of Petroleum Engineers to set up data banks on the properties of sedimentary rocks encountered during drilling. Computer-based data banks of complete rock properties will be organized for sandstones (GRESA), shales (ARSHA) and carbonates (CARCA). The commission hopes to access data sources from members of the commission, private companies and the public domain.

  7. 21 CFR 522.313a - Ceftiofur crystalline free acid.

    Science.gov (United States)

    2010-04-01

    ... dairy cattle. (ii) Indications for use. For the treatment of bovine respiratory disease (BRD, shipping.... (2) Cattle. The formulation described in paragraph (a)(2) of this section is used as follows: (i... it attaches to the head (base of the ear) in beef and non-lactating dairy cattle. For...

  8. Dissolution of Olivine, Siderite, and Basalt at 80 Deg C in 0.1 M H2SO4 in a Flow Through Process: Insights into Acidic Weathering on Mars

    Science.gov (United States)

    Golden, D. C.; Ming, D. W.; Hausrath, E. M.; Morris, R. V.; Niles, P. B.; Achilles, C. N.; Ross, D. K.; Cooper, B. L.; Gonzalex, C. P.; Mertzman, S. A.

    2012-01-01

    The occurrence of jarosite, other sulfates (e.g., Mg-and Ca-sulfates), and hematite along with silicic-lastic materials in outcrops of sedimentary materials at Meridiani Planum (MP) and detection of silica rich deposits in Gusev crater, Mars, are strong indicators of local acidic aqueous processes [1,2,3,4,5]. The formation of sediments at Meridiani Planum may have involved the evaporation of fluids derived from acid weathering of Martian basalts and subsequent diagenesis [6,7]. Also, our previous work on acid weathering of basaltic materials in a closed hydro-thermal system was focused on the mineralogy of the acid weathering products including the formation of jarosite and gray hematite spherules [8,9,10]. The object of this re-search is to extend our earlier qualitative work on acidic weathering of rocks to determine acidic dissolution rates of Mars analog basaltic materials at 80 C using a flow-thru reactor. We also characterized residual phases, including poorly crystalline or amorphous phases and precipitates, that remained after the treatments of olivine, siderite, and basalt which represent likely MP source rocks. This study is a stepping stone for a future simulation of the formation of MP rocks under a range of T and P.

  9. Rock and mineral magnetism

    CERN Document Server

    O’Reilly, W

    1984-01-01

    The past two decades have witnessed a revolution in the earth sciences. The quantitative, instrument-based measurements and physical models of. geophysics, together with advances in technology, have radically transformed the way in which the Earth, and especially its crust, is described. The study of the magnetism of the rocks of the Earth's crust has played a major part in this transformation. Rocks, or more specifically their constituent magnetic minerals, can be regarded as a measuring instrument provided by nature, which can be employed in the service of the earth sciences. Thus magnetic minerals are a recording magnetometer; a goniometer or protractor, recording the directions of flows, fields and forces; a clock; a recording thermometer; a position recorder; astrain gauge; an instrument for geo­ logical surveying; a tracer in climatology and hydrology; a tool in petrology. No instrument is linear, or free from noise and systematic errors, and the performance of nature's instrument must be assessed and ...

  10. Uranium in alkaline rocks

    International Nuclear Information System (INIS)

    Geologic and geochemical criteria were developed for the occurrence of economic uranium deposits in alkaline igneous rocks. A literature search, a limited chemical analytical program, and visits to three prominent alkaline-rock localities (Ilimaussaq, Greenland; Pocos de Caldas, Brazil; and Powderhorn, Colorado) were made to establish criteria to determine if a site had some uranium resource potential. From the literature, four alkaline-intrusive occurrences of differing character were identified as type-localities for uranium mineralization, and the important aspects of these localities were described. These characteristics were used to categorize and evaluate U.S. occurrences. The literature search disclosed 69 U.S. sites, encompassing nepheline syenite, alkaline granite, and carbonatite. It was possible to compare two-thirds of these sites to the type localities. A ranking system identified ten of the sites as most likely to have uranium resource potential

  11. Uranium in alkaline rocks

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, M.; Wollenberg, H.; Strisower, B.; Bowman, H.; Flexser, S.; Carmichael, I.

    1978-04-01

    Geologic and geochemical criteria were developed for the occurrence of economic uranium deposits in alkaline igneous rocks. A literature search, a limited chemical analytical program, and visits to three prominent alkaline-rock localities (Ilimaussaq, Greenland; Pocos de Caldas, Brazil; and Powderhorn, Colorado) were made to establish criteria to determine if a site had some uranium resource potential. From the literature, four alkaline-intrusive occurrences of differing character were identified as type-localities for uranium mineralization, and the important aspects of these localities were described. These characteristics were used to categorize and evaluate U.S. occurrences. The literature search disclosed 69 U.S. sites, encompassing nepheline syenite, alkaline granite, and carbonatite. It was possible to compare two-thirds of these sites to the type localities. A ranking system identified ten of the sites as most likely to have uranium resource potential.

  12. Search for unconventional methane resources beneath crystalline thrust sheets in the southern Appalachians

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, K.; Costain, J.K.; Bodnar, R.J.; Coruh, C. (Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States). Dept. of Geological Sciences); Henika, W.S.

    1994-03-01

    The crystalline rocks of the Virginia Blue Ridge and Piedmont provinces are generally not thought to be likely targets for natural gas exploration. However, recent fluid inclusion studies have documented the presence of methane in post-Alleghanian quartz veins in the Blue Ridge and Piedmont. Methane is not a stable component of the COH fluid phase predicted to be in equilibrium with these rocks at the P-T conditions of metamorphism. This suggests that the methane is not generated locally but, rather, is derived from other sources. Sedimentary rocks equivalent to the productive hydrocarbon Devonian shale beds of the Appalachian Basin are present in surficial tectonic slices on the Reed Mountain and Coyner Mountain structures in the roanoke area, and Devonian shale source beds are thought to exist beneath the Pulaski and Blue Ridge thrust sheets to the southeast. These source beds are part of the hydrocarbon-bearing Lower Paleozoic shelf strata that are interpreted to be buried beneath the crystalline thrust sheets in the Southern Appalachians.

  13. Limados : Rock peruano

    OpenAIRE

    García Morete, Ramiro

    2013-01-01

    Incentivado por la corriente nuevaolera que llegaba de México, fue señalado por especialistas como pionero del punk. Aunque el plan, era tocar con lo que hubiera. Un recodo ínfimo de un período breve pero sorprendentemente poderoso, los 60 en un país que hizo del rock una expresión propia de su cultura.

  14. Deformations of fractured rock

    International Nuclear Information System (INIS)

    Results of the DBM and FEM analysis in this study indicate that a suitable rock mass for repository of radioactive waste should be moderately jointed (about 1 joint/m2) and surrounded by shear zones of the first order. This allowes for a gentle and flexible deformation under tectonic stresses and prevent the development of large cross-cutting failures in the repository area. (author)

  15. Transient Flow Of Thermotropic Liquid-Crystalline Polymers in Step Strain Experiments

    OpenAIRE

    Done, D.; Baird, Donald G.

    1990-01-01

    The transient response of two thermotropic liquid crystalline polymers (a copolyester of 60 mol_% p_hydroxybenzoic acid, PHB, and 40 mol_% poly(ethylene terephthalate), PET, and a copolyester of PHB and 2_hydroxy_6_naphthoic acid, following step strains up to 20 strain units was measured. The relaxation curves typically show an initially rapid decay followed by a long relaxation tail. The lower the temperature, the more remarkable is the length of the long relaxation tail. This behavior makes...

  16. Reorientation of lineation in the Central Crystalline Zone, Munsiari–Milam area of the Kumaun Greater Himalaya

    Indian Academy of Sciences (India)

    A K Verma; A R Bhattacharya

    2015-03-01

    During large scale ductile shear deformation, linear features of the rocks tend to be reoriented towards the direction of bulk shear. This is demonstrated in a crustal scale shear zone of the Himalaya, the Main Central Thrust (MCT), typically exposed in the Munsiari–Milam area of eastern Kumaun Greater Himalaya. Along the MCT, the crystalline rocks of the Greater Himalaya are thrust over the younger sedimentary belt of the Lesser Himalaya. In the study area, the scatter of lineation orientation in the vicinity of the MCT has been observed to drastically reduce within 27° in a zone of about 18 km (about 13 km in the crystalline rocks and about 5 km in the sedimentary rocks). Beyond this zone, the scatter is very high, up to 70° or more. The low scatter of lineation orientation around the MCT could be related to the strong ductile shear deformation associated with the movement along this thrust due to which the linear features got reoriented towards the direction of bulk shear. Away from this zone, ductile shearing had negligible or no effect on the rocks and, therefore, the scatter of lineation remains very high.

  17. Rock pushing and sampling under rocks on Mars

    Science.gov (United States)

    Moore, H.J.; Liebes, S.; Crouch, D.S.; Clark, L.V.

    1978-01-01

    Viking Lander 2 acquired samples on Mars from beneath two rocks, where living organisms and organic molecules would be protected from ultraviolet radiation. Selection of rocks to be moved was based on scientific and engineering considerations, including rock size, rock shape, burial depth, and location in a sample field. Rock locations and topography were established using the computerized interactive video-stereophotogrammetric system and plotted on vertical profiles and in plan view. Sampler commands were developed and tested on Earth using a full-size lander and surface mock-up. The use of power by the sampler motor correlates with rock movements, which were by plowing, skidding, and rolling. Provenance of the samples was determined by measurements and interpretation of pictures and positions of the sampler arm. Analytical results demonstrate that the samples were, in fact, from beneath the rocks. Results from the Gas Chromatograph-Mass Spectrometer of the Molecular Analysis experiment and the Gas Exchange instrument of the Biology experiment indicate that more adsorbed(?) water occurs in samples under rocks than in samples exposed to the sun. This is consistent with terrestrial arid environments, where more moisture occurs in near-surface soil un- der rocks than in surrounding soil because the net heat flow is toward the soil beneath the rock and the rock cap inhibits evaporation. Inorganic analyses show that samples of soil from under the rocks have significantly less iron than soil exposed to the sun. The scientific significance of analyses of samples under the rocks is only partly evaluated, but some facts are clear. Detectable quantities of martian organic molecules were not found in the sample from under a rock by the Molecular Analysis experiment. The Biology experiments did not find definitive evidence for Earth-like living organisms in their sample. Significant amounts of adsorbed water may be present in the martian regolith. The response of the soil

  18. Lipase degradation of Dynasan 114 and 116 solid lipid nanoparticles (SLN)--effect of surfactants, storage time and crystallinity.

    Science.gov (United States)

    Olbrich, Carsten; Kayser, Oliver; Müller, Rainer H

    2002-04-26

    In vivo drug release from solid lipid nanoparticles (SLN) takes place by diffusion and degradation of the lipid matrix. SLN with different degree of crystallinity were prepared to study the effect of crystallinity on the degradation velocity. These SLN were produced by using glycerides with different length of fatty acid chains and known differences in crystallisation velocity (Dynasan 114 and 116), and using stabilisers interfering differently with the crystallisation process of the lipid matrix (cholic acid sodium salt (NaCh), Poloxamer 407 (Plx 407)). NaCh disturbs the crystallisation process, Poloxamer shows little interference. The particles were characterised by photon correlation spectroscopy (PCS) and differential scanning calorimetry (DSC), degradation velocity was determined directly after production and during storage up to 4 weeks under different storage conditions using an especially developed assay based on the NEFA Test kit. After production, SLN with a lower crystallinity matrix (Dynasan 114 and 116, NaCh) degraded faster than higher crystalline particles (all SLN with Plx 407), and showed a decrease in degradation velocity with increasing crystallinity during storage. Fast crystallising particles made from Dynasan 116 stabilised with the non-interfering Plx 407 showed no change in the degradation velocity during storage. SLN produced with a higher crystalline lipid in combination with the crystallisation-disturbing NaCh (Dynasan 116, NaCh) required a 'ripening time' to reach sufficient crystallinity. PMID:11955810

  19. Improved Josephson Qubits incorporating Crystalline Silicon Dielectrics

    Science.gov (United States)

    Gao, Yuanfeng; Maurer, Leon; Hover, David; Patel, Umeshkumar; McDermott, Robert

    2010-03-01

    Josephson junction phase quibts are a leading candidate for scalable quantum computing in the solid state. Their energy relaxation times are currently limited by microwave loss induced by a high density of two-level state (TLS) defects in the amorphous dielectric films of the circuit. It is expected that the integration of crystalline, defect-free dielectrics into the circuits will yield substantial improvements in qubit energy relaxation times. However, the epitaxial growth of a crystalline dielectric on a metal underlayer is a daunting challenge. Here we describe a novel approach in which the crystalline silicon nanomembrane of a Silicon-on-Insulator (SOI) wafer is used to form the junction shunt capacitor. The SOI wafer is thermocompression bonded to the device wafer. The handle and buried oxide layers of the SOI are then etched away, leaving the crystalline silicon layer for subsequent processing. We discuss device fabrication issues and present microwave transport data on lumped-element superconducting resonators incorporating the crystalline silicon.

  20. Efficient aziridine synthesis in metastable crystalline phases by photoinduced denitrogenation of crystalline triazolines.

    Science.gov (United States)

    de Loera, Denisse; Garcia-Garibay, Miguel A

    2012-08-01

    The solid-state photodenitrogenation of crystalline triazolines proceeds with high efficiency to form the corresponding aziridines in high chemical yields upon selection of the proper irradiation wavelength. It was shown that the solid-to-solid reactions occur by formation of the product in metastable crystalline phases. PMID:22794188

  1. Rock in Rio: forever young

    Directory of Open Access Journals (Sweden)

    Ricardo Ferreira Freitas

    2014-12-01

    Full Text Available The purpose of this article is to discuss the role of Rock in Rio: The Musical, as herald of megafestival Rock in Rio. Driven by the success that musicals have reached in Brazil, we believe that the design of this spectacle of music, dance and staging renews the brand of the rock festival, once it adds the force of young and healthy bodies to its concept. Moreover, the musical provides Rock in Rio with some distance from the controversal trilogy of sex, drugs and rock and roll, a strong mark of past festivals around the world. Thus, the musical expands the possibilities of growth for the brand.

  2. X-Ray Diffraction Analysis of Organic Soil: Crystalline Size of Mineral Phase

    International Nuclear Information System (INIS)

    Organic soil, in nature, is a very complex material and varies widely, which derived from weathered rock and organic substances. The contents and behaviour of the organic soil are site dependent and no certainty that a soil will be having same contents even within the vicinity. Traditionally, soil is categorized based on particle size regardless the mineral contents. Hence, the main objective of this study is to identify the mineral phases of the soil qualitatively and its crystalline size quantitatively by using X-Ray Diffraction analysis, in order to have a better understanding of the material. Commercial packed organic soil with pre-determined contents was utilized in this study. The possible mineral phases of the organic soil were determined by comparing the x-ray diffraction spectrum with the ICDD database. The crystalline size of the specific mineral phases was estimated by using Williamson- Hall plot. The findings of this study showed that crystalline size of the mineral phases in the soil are too small to be estimated using XRD except mineral quartz. The crystalline size of mineral quartz is estimated in the range of 63 nm to 126 nm by using Williamson-Hall plot. (author)

  3. Mesogen-jacketed liquid crystalline polymers.

    Science.gov (United States)

    Chen, Xiao-Fang; Shen, Zhihao; Wan, Xin-Hua; Fan, Xing-He; Chen, Er-Qiang; Ma, Yuguo; Zhou, Qi-Feng

    2010-08-01

    This critical review covers the recent progress in the research of mesogen-jacketed liquid crystalline polymers (MJLCPs), special side-on side-chain liquid crystalline polymers with very short spacers or without spacers. MJLCPs can self-organize into supramolecular columnar phases with the polymer chains aligned parallel to one another or smectic phases with the backbones embedded in the smectic layers. The semi-rigid rod-like MJLCP with a tunable rod shape in both length and diameter provides an excellent building block in designing novel rod-coil liquid crystalline block copolymers which can self-assemble into hierarchical supramolecular nanostructures depending on the competition between liquid crystal formation and microphase separation (229 references). PMID:20559597

  4. Irreducible tensor operators and crystalline potentials

    International Nuclear Information System (INIS)

    It is often accepted that the effects of its neighbourhood on the quantum state of an ion A may be obtained by the model of the crystalline effective field approximation. Within this assumption Stevens has developed a method which provides equivalent operators that facilitate the calculation of the matrix elements of the crystalline field in a given multiplicity. This method has been extended here. We demonstrate that in the expansion of the crystalline field in powers of the electrons coordinates of the ion A - for electrons of the same sub-shell of A - only even terms can contribute. Equivalent operators and matrix elements, in a given multiplicity, are given for these development terms - up to order 6 - and for potential invariant by the operations of one of the thirty-two point-groups. (author)

  5. Structural changes in bunched crystalline ion beams

    International Nuclear Information System (INIS)

    Measurements of the spatial distribution of bunched crystalline ion beams in the radio frequency quadrupole storage ring PALLAS are presented for different ratios of the longitudinal and the transverse confinement strengths. The length of highly elongated crystalline ion bunches and its dependence on the bunching voltage is compared to predictions for a one-dimensional ion string and three-dimensional space-charge-dominated beams. The length is found to be considerably shorter than that predicted by the models. Furthermore, the scaling of the length with the bunching voltage is shown to differ from the expected inverse cube root scaling. These differences can partially be attributed to the formation of a mixed crystalline structure. Additionally, a concise mapping of the structural transition from a string to a zig-zag configuration as a function of the ratio of the confinement strengths is presented, which in a similar way deviates from the predictions

  6. Structural changes in bunched crystalline ion beams

    CERN Document Server

    Bussmann, M; Schätz, T; Habs, D

    2003-01-01

    Measurements of the spatial distribution of bunched crystalline ion beams in the radio frequency quadrupole storage ring PALLAS are presented for different ratios of the longitudinal and the transverse confinement strengths. The length of highly elongated crystalline ion bunches and its dependence on the bunching voltage is compared to predictions for a one-dimensional ion string and three-dimensional space-charge-dominated beams. The length is found to be considerably shorter than that predicted by the models. Furthermore, the scaling of the length with the bunching voltage is shown to differ from the expected inverse cube root scaling. These differences can partially be attributed to the formation of a mixed crystalline structure. Additionally, a concise mapping of the structural transition from a string to a zig-zag configuration as a function of the ratio of the confinement strengths is presented, which in a similar way deviates from the predictions.

  7. Rock bolts - Improved design and possibilities

    OpenAIRE

    Thomas-Lepine, Capucine

    2012-01-01

    SummaryRock Bolts, improved design and possibilitiesMaster thesis NTNU 2012Student : Capucine Thomas-LepineSupervisor : Leif LiaKey words : rock foundation, small concrete dam, rock mass classification, rock joints, shear strength of rock discontinuities, fully grouted passive rock bolts designMasters Thesis : “Rock bolts, improved design and possibilities” is a continuation from the Masters Thesis NTNU 2011 “Rock bolts in dams, expected capacity” by Lars Kristian Neby. In...

  8. FEBEX: Full-Scale engineered barriers experiment in crystalline host-rock: preoperational phase. Synthesized report

    International Nuclear Information System (INIS)

    The FEBEX project is being cofinanced by the EC under contract F 14WCT950006. In addition to the EC, seven partners from three countries of the EU. (France, Germany, and Spain) as well as one from EFTA (Switzerland) are participating in the project. ENRESA is the coordinating partner with NAGRA assisting in coordinating some aspects. The project consists of two large-scale tests and a series of complimentary laboratory tests. The work is being executed by the following organizations: CIEMAT, AITEMIN, UP-DIT (CIMNE), ULC, CSIC-Zaidin, and UPM (SPAIN) ANDRA and G.3S (FRANCE) GRS (GERMANY). This report includes a synthesized description of the experiment from its conception through the installation of the two large-scale tests (from the middle of 1994 to the beginning of 1997, preoperation stage). The experiment is described in detail in a series of specific reports. (Author)

  9. Stability of deep-sited smectite minerals in crystalline rock-chemical aspects

    International Nuclear Information System (INIS)

    A recent survey of possible conditions and mechanisms of smectite alteration, with special respect to the Swedish concept of radioactive waste disposal, has shown that the charge change by replacement of tetrahedral Si by Al is the key mechanism of the only practically important alteration, namely that of smectite/illite conversion. If K is available in sufficient quantities it will be fixed and permanent conversion to the unwanted illite-type minerals is a fact; if not, the smectite will be beidellitelike with practically unchanged physico/mechanical properties. Heating to more than about 100degreeC is thought to be the cause of the charge change. One other process may be critical and that is cementation of various substances. A possible cementation mechanism, i.e. that of quartz precipitation, is very probably associated with the smectite/illite conversion. Practical examples of smectite alteration and survival under reasonably well documented geological conditions with respect to temperature and pressure are available, one being that of the Kinnekulle bentonites, another one, although less well known, being the smectitic clay beds in the Hoeganaes depression. Rather comprehensive core sampling was made at both sites and elemental and mineral analyses were conducted as well as microstructural studies. They support the hypothesis that practically important charge change through Si/Al replacement requires a temperature of more than 100degreeC, and that such replacement does not yield permanent lattice collapse unless K is available in sufficient quantities. The Hoeganaes case also serves as an example of drastic loss in plasticity and swelling potential by cementation of other precipitates than quartz, namely iron compounds. (author)

  10. Abundances of uranium, thorium, and potassium for some Australian crystalline rocks

    Science.gov (United States)

    Bunker, Carl Maurice; Bush, C.A.; Munroe, Robert J.; Sass, J.H.

    1975-01-01

    This report contains a tabulation of the basic radioelement and radiogenic heat data obtained during an Australian National University (ANU) - United States Geological Survey (USGS) heat-flow project, directed jointly by J. C. Jaeger (ANU) and J. H. Sass (USGS). Most samples were collected during the periods June through September, 1971 and 1972. The measurements were made subsequently by two of us (C. M. Bunker and C. A. Bush) using the gamma-ray spec trometric techniques described by Bunker and Bush (1966, 1967). Interpreting the spectra for quantitative analyses of the radioelements was accomplished with an iterative leastsquares computer program modified from one by Schonfeld (1966). Uranium content determined by gamma-ray spectrometry is based on a measurement of the daughter products of 226Ra. Equilibrium in the uranium-decay series was assumed for these analyses . Throughout the report, when U content is stated, radium-equivalent uranium is implied. The coefficient of variation for the accuracy of the radioelement data, when compared to ana lyses by isotope dilution and flame photometry is about 3 percent for radium-equivalent uranium and thorium and about 1 percent for potassium. These percentages are in addition to minimum standard deviations of about 0.05 ppm for U and Th, and about 0.03 percent for K.

  11. Tuning the phase diagrams: the miscibility studies of multilactate liquid crystalline compounds

    Science.gov (United States)

    Bubnov, Alexej; Tykarska, Marzena; Hamplová, Věra; Kurp, Katarzyna

    2016-09-01

    Design of binary and multicomponent liquid crystalline mixtures is a very powerful tool to reach the desired self-assembling properties. Beyond many advantages, this method has a distinct negativity - it is very material-consuming. While working with unique chiral materials in the research laboratory, this problem can be solved by applying miscibility study by the contact preparation method. In this work, the miscibility studies of lactic acid derivatives and non-chiral/chiral liquid crystalline molecules of different structure have been done in order to establish the phase diagrams. Special attention is focused on the ferro(antiferro)electric smectic phases.

  12. Crystalline Repository Project: Review and comment of the Leech Lake Reservation Business Committee: Draft area recommendation report

    International Nuclear Information System (INIS)

    The Leech Lake Reservation Business Committee (LLRBC) has reviewed five documents related to the US Department of Energy's Crystalline Repository Project (CRP). They are the ''National Survey of Crystalline Rocks,'' ''General Guidelines for the Recommendation of Sites for the Nuclear Waste Repositories;' Final Siting Guidelines (10 CFR Part 960),'' ''Regional Characterization Reports for the North Central Region,'' the ''Region to Area Screening Methodology Document'' (SMD) and the ''Draft Area Recommendation Report'' (DARR). The comments and discussions of issues contained in this review will be considered in the preparation of the Final Area Recommendation Report, which will formally identify potentially acceptable sites for a second national repository for the permanent disposal of high level nuclear waste. Following a review of the above referenced documents, the LLRBC has concluded that the identification of potentially acceptable sites in the Draft Area Recommendation Report is based upon inferior and incomplete technical information being applied to a flawed screening process which, among other deficiencies, pays little attention to the importance of hydrological factors in the siting process. Although the DOE prefers that comments from states and tribes be directed at the Draft Area Recommendation Report alone, the Leech Lake Reservation Business Committee is extremely concerned about inadequacies in the ''National Survey of Crystalline Rocks'' (ORCD-1), which serves as the foundation for all siting work done to date. The national survey was conducted utilizing little of the time or staffing required for this important phase of the Crystalline Repository Program. As a result, the national survey is based upon out-of-date scientific literature, exaggerates certain screening variables that favor the selection of regions in the eastern US and arbitrarily eliminated the few western crystalline rock bodies that passed the questionable screening process utilized

  13. Groundwater flow and sorption processes in fractured rocks (I)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Won Young; Woo, Nam Chul; Yum, Byoung Woo; Choi, Young Sub; Chae, Byoung Kon; Kim, Jung Yul; Kim, Yoo Sung; Hyun, Hye Ja; Lee, Kil Yong; Lee, Seung Gu; Youn, Youn Yul; Choon, Sang Ki [Korea Institute of Geology Mining and Materials, Taejon (Korea, Republic of)

    1996-12-01

    This study is objected to characterize groundwater flow and sorption processes of the contaminants (ground-water solutes) along the fractured crystalline rocks in Korea. Considering that crystalline rock mass is an essential condition for using underground space cannot be overemphasized the significance of the characterizing fractured crystalline rocks. the behavior of the groundwater contaminants is studied in related to the subsurface structure, and eventually a quantitative technique will be developed to evaluate the impacts of the contaminants on the subsurface environments. The study has been carried at the Samkwang mine area in the Chung-Nam Province. The site has Pre-Cambrian crystalline gneiss as a bedrock and the groundwater flow system through the bedrock fractures seemed to be understandable with the study on the subsurface geologic structure through the mining tunnels. Borehole tests included core logging, televiewer logging, constant pressure fixed interval length tests and tracer tests. The results is summarized as follows; 1) To determine the hydraulic parameters of the fractured rock, the transient flow analysis produce better results than the steady - state flow analysis. 2) Based on the relationship between fracture distribution and transmissivities measured, the shallow part of the system could be considered as a porous and continuous medium due to the well developed fractures and weathering. However, the deeper part shows flow characteristics of the fracture dominant system, satisfying the assumptions of the Cubic law. 3) Transmissivities from the FIL test were averaged to be 6.12 x 10{sup -7}{sub m}{sup 2}{sub /s}. 4) Tracer tests result indicates groundwater flow in the study area is controlled by the connection, extension and geometry of fractures in the bedrock. 5) Hydraulic conductivity of the tracer-test interval was in maximum of 7.2 x 10{sup -6}{sub m/sec}, and the effective porosity of 1.8 %. 6) Composition of the groundwater varies

  14. Electronic processes in non-crystalline materials

    CERN Document Server

    Mott, Nevill Francis

    2012-01-01

    Since the first edition of this highly successful book the field saw many great developments both in experimental and theoretical studies of electrical properties of non-crystalline solids. It became necessary to rewrite nearly the whole book, while the aims of the second edition remained the same: to set out the theoretical concepts, to test them by comparison with experiment for a wide variety of phenomena, and to apply them to non-crystalline materials. Sir Nevill Mott shared the1977 Nobel Prize for Physics, awarded for his research work in this field. The reissue of this book as part of th

  15. Observation of atomic collisions in crystalline solids

    CERN Document Server

    Nelson, R S; Gevers, R

    2013-01-01

    The Observation of Atomic Collisions in Crystalline Solids presents a critical account of the more important experiments which have provided the basis for a better understanding of atomic collision phenomena in crystalline solids. Collisions have been divided into two artificial regimes; primary collisions which deal with the interaction of the incident particles with the solid, and secondary collisions which deal with those events which occur as a result of lattice atoms recoiling from primary encounters. Although the book is intended principally for the experimentalist some simple theoretica

  16. Crystalline Fullerenes. Round Pegs in Square Holes

    OpenAIRE

    Fleming, R. M.; Hessen, B.; Siegrist, T.; Kortan, A.R.; Marsh, P; Tycko, R.; Dabbagh, G.; Haddon, R C

    1992-01-01

    The fullerenes C60 and C70 act as spherical building blocks in crystalline solids to form a variety of crystal structures. In many cases, the icosahedral molecular symmetry of C60 appears to play little role in determining the crystal structure. In this chapter we discuss our results on the crystallography of pure and solvated fullerenes and some general features of fullerenes as building units in crystalline solids. For pure C60 or C70, the face-centered cubic arrangement is preferred. In so...

  17. Tensile Deformation of Polyethylenes: Crystallinity Effects

    Science.gov (United States)

    Crist, Buckley; Metaxas, Costas

    2004-03-01

    The crystalline fraction of polyethylene can be reduced by increasing the cooling rate, the molecular weight or the fraction of comonomer. All three methods have been used in this study of tensile deformation which shows that true stress - true strain behavior depends systematically on morphology. The dependence of uniaxial yield stress on crystal thickness is well understood in terms of dislocation nucleation. Post yield flow is dominated by the strain hardening rate that is larger in polyethylenes of lower crystallinity. Noncrystalline polymer evidently reduces the plastic compliance while providing for elastic (reversible) strains. These observations are examined in terms of old and new theories for deformation of semicrystalline polymers.

  18. Monolithic aerogels with nanoporous crystalline phases

    Science.gov (United States)

    Daniel, Christophe; Guerra, Gaetano

    2015-05-01

    High porosity monolithic aerogels with nanoporous crystalline phases can be obtained from syndiotactic polystyrene and poly(2,6-dimethyl-1,4-phenylene)oxide thermoreversible gels by removing the solvent with supercritical CO2. The presence of crystalline nanopores in the aerogels based on these polymers allows a high uptake associated with a high selectivity of volatile organic compounds from vapor phase or aqueous solutions even at very low activities. The sorption and the fast kinetics make these materials particularly suitable as sorption medium to remove traces of pollutants from water and moist air.

  19. Exact Topological Twistons in Crystalline Polyethylene

    CERN Document Server

    Ventura, E; Bazeia, D

    2000-01-01

    We investigate the presence of topological twistons in crystalline polyethylene. We describe crystalline polyethylene with a model that couples the torsional and longitudinal degrees of freedom of the polymeric chain by means of a system of two real scalar fields. This model supports topological twistons, which are described by exact and stable topological solutions that appear when the interaction between torsional and longitudinal fields is polynomial, containing up to the sixth power in the fields. We calculate the energy of the topological twiston, and the result is in very good agreement with the value obtained via molecular simulation.

  20. Rock mechanics for hard rock nuclear waste repositories

    International Nuclear Information System (INIS)

    The mined geologic burial of high level nuclear waste is now the favored option for disposal. The US National Waste Terminal Storage Program designed to achieve this disposal includes an extensive rock mechanics component related to the design of the wastes repositories. The plan currently considers five candidate rock types. This paper deals with the three hard rocks among them: basalt, granite, and tuff. Their behavior is governed by geological discontinuities. Salt and shale, which exhibit behavior closer to that of a continuum, are not considered here. This paper discusses both the generic rock mechanics R and D, which are required for repository design, as well as examples of projects related to hard rock waste storage. The examples include programs in basalt (Hanford/Washington), in granitic rocks (Climax/Nevada Test Site, Idaho Springs/Colorado, Pinawa/Canada, Oracle/Arizona, and Stripa/Sweden), and in tuff

  1. Sealing of fractured rock

    International Nuclear Information System (INIS)

    This paper consists of a presentation of the third phase of the Stripa Project. This phase was dedicated to fracture sealing. First of all it has been necessary to show that fine-grained grouts could effectively be injected in relatively fine cracks, and that the fluidity of bentonite could also be enhanced. The field tests comprised investigation of excavation-induced disturbance and attempts to seal disturbed rock, and, in separate tests, grouting of deposition holes and a natural fine-fracture zone. (TEC). 12 figs., 1 tab., 6 refs

  2. From stones to rocks

    Science.gov (United States)

    Mortier, Marie-Astrid; Jean-Leroux, Kathleen; Cirio, Raymond

    2013-04-01

    With the Aquila earthquake in 2009, earthquake prediction is more and more necessary nowadays, and people are waiting for even more accurate data. Earthquake accuracy has increased in recent times mainly thanks to the understanding of how oceanic expansion works and significant development of numerical seismic prediction models. Despite the improvements, the location and the magnitude can't be as accurate as citizen and authorities would like. The basis of anticipating earthquakes requires the understanding of: - The composition of the earth, - The structure of the earth, - The relations and movements between the different parts of the surface of the earth. In order to answer these questions, the Alps are an interesting field for students. This study combines natural curiosity about understanding the predictable part of natural hazard in geology and scientific skills on site: observing and drawing landscape, choosing and reading a representative core drilling, replacing the facts chronologically and considering the age, the length of time and the strength needed. This experience requires students to have an approach of time and space radically different than the one they can consider in a classroom. It also limits their imagination, in a positive way, because they realize that prediction is based on real data and some of former theories have become present paradigms thanks to geologists. On each location the analyzed data include landscape, core drilling and the relation established between them by students. The data is used by the students to understand the meaning, so that the history of the formation of the rocks tells by the rocks can be explained. Until this year, the CBGA's perspective regarding the study of the Alps ground allowed students to build the story of the creation and disappearance of the ocean, which was a concept required by French educational authorities. But not long ago, the authorities changed their scientific expectations. To meet the

  3. Rock mechanics data package

    International Nuclear Information System (INIS)

    This data package provides a summary of available laboratory and in situ stress field test results from site characterization investigations by the Basalt Waste Isolation Project Modeling and Analysis Group. The objective is to furnish rock mechanics information for use by Rockwell Hanford Operations and their subcontractors in performance assessment and engineering studies. This release includes Reference Repository Location (RRL) site specific laboratory and field test data from boreholes RRL-2, RRL-6, and RRL-14 as well as previous Hanford wide data available as of April, 1985. 25 refs., 9 figs., 16 tabs

  4. Technical review of US Department of Energy draft area recommendation report for the crystalline repository project

    International Nuclear Information System (INIS)

    Foth and Van Dyke and Associates Inc. was retained by the Stockbridge-Munsee Community to evaluate the DOE's screening process for selection of candidate areas in crystalline rock terranes, and critically review the geologic and environmental factors utilized by the DOE in selecting the NC-3 area as a potentially acceptable site (PAS). We have reviewed the DOE's Draft Area Recommendation Report (ARR) issued in January 1986, and prepared our comments. In addition, geologic and environmental data pertaining to the Stockbridge-Munsee community and vicinity that was not included in the Draft ARR is presented. 24 refs., 7 figs., 4 tabs

  5. Quasi-crystalline geometry for architectural structures

    DEFF Research Database (Denmark)

    Wester, Ture; Weinzieri, Barbara

    The quasi-crystal (QC) type of material was discovered in 1983 by Dan Schechtman from Technion, Haifa. This new crystalline structure of material broke totally with the traditional conception of crystals and geometry introducing non-periodic close packing of cells with fivefold symmetry in 3D spa...

  6. Crystalline Fullerenes. Round Pegs in Square Holes

    NARCIS (Netherlands)

    Fleming, R.M.; Hessen, B.; Siegrist, T.; Kortan, A.R.; Marsh, P.; Tycko, R.; Dabbagh, G.; Haddon, R.C.

    1992-01-01

    The fullerenes C60 and C70 act as spherical building blocks in crystalline solids to form a variety of crystal structures. In many cases, the icosahedral molecular symmetry of C60 appears to play little role in determining the crystal structure. In this chapter we discuss our results on the crystall

  7. The critical exponents of crystalline random surfaces

    CERN Document Server

    Wheater, John F

    1995-01-01

    We report on a high statistics numerical study of the crystalline random surface model with extrinsic curvature on lattices of up to 64^2 points. The critical exponents at the crumpling transition are determined by a number of methods all of which are shown to agree within estimated errors. The correlation length exponent is found to be \

  8. Genetics Home Reference: Bietti crystalline dystrophy

    Science.gov (United States)

    ... Hayakawa M, Kanai A, Shy Chen M, Alan Lewis R, Heckenlively J, Weleber RG, Traboulsi EI, Zhang Q, Xiao X, Kaiser-Kupfer M, Sergeev YV, Hejtmancik JF. Bietti crystalline corneoretinal dystrophy is caused by mutations in the novel gene CYP4V2. Am J Hum Genet. 2004 May;74( ...

  9. Crystalline damage development during martensitic transformations

    NARCIS (Netherlands)

    Suiker, A.S.J.; Turteltaub, S.R.

    2006-01-01

    A recently developed thermo-mechanical model [1] is presented that can be used to simulate the interactions between martensitic phase transformations and crystalline damage growth at the austenitic grain level. Subgrain information is included in the model via the crystallographic theory of martensi

  10. Immobilization of polyoxometalates in crystalline solids for highly efficient heterogeneous catalysis.

    Science.gov (United States)

    Ye, Ji-Jie; Wu, Chuan-De

    2016-06-21

    Polyoxometalates (POMs) are a unique class of molecular metal-oxygen clusters with attractive architecture and tunable properties. Due to their strong acidity, redox chemistry, photoactivity, charge distribution and multielectron transformation, POMs have been used as efficient catalysts in a variety of chemical reactions. To meet the requirement of sustainable chemistry, great effort has been focused on immobilization of the active POMs on different solid supports to realize heterogeneous catalysis. This short review summarizes the recent progress on immobilization of POM moieties in crystalline solids with defined crystal structures, including organic-inorganic hybrid materials, POM-based inorganic crystalline solids and POM-encapsulated metal-organic frameworks (POM@MOFs), and their catalytic properties in oxidation, hydrolysis, cyanosilylation, photocatalysis and electrocatalysis. As illustrated in the text, these crystalline solids exhibit interesting catalytic properties, such as high activity, stability and selectivity, and simple recovery and easy recycling, which are much superior to those of the corresponding constituent species in most cases.