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Sample records for beryl

  1. Rare Earth Elements Distribution in Beryl

    International Nuclear Information System (INIS)

    Laser ablation method is applied to a double focusing inductively coupled plasma mass spectrometer to determine the rare earth element distribution in some selected beryl samples. White, green and blue beryl samples are selected from the Egyptian eastern desert. Distributions of chondrite- normalized plot for the rare earth element in the selected beryl samples are investigated

  2. Determination of helium in beryl minerals

    International Nuclear Information System (INIS)

    In order to obtain the diffusion coefficients of helium in beryl and phenacite samples at various temperatures, helium leak rates were measured in these minerals at these temperatures. Mass spectrometry (MS) was used to obtain helium leak rates and the gas flow was plotted against time. The gas quantity determined by MS was first obtained at various temperatures until no helium leak rate was detected. After that, these samples were irradiated with fast neutrons to produce helium which was measured again. This procedure was used to estimate the experimental error. The quantity of helium produced by interaction of gamma radiation with beryl minerals was theoretically calculated from the amount of thorium-232 at the neighbourhood of the samples. The quantity of helium produced in the minerals due to uranium and thorium decay was calculated using the amount of these heavy elements, and the results were compared with the amounts determined by MS. The amount of potassium-40 was determined in order to derive the quantity of argonium-40, since some workers found argonium in excess in these minerals. The quantity of helium in the beryl samples (s) was determined in the center and in the surface of the samples in order to obtain informations about the effectiveness of the Be(α, η) He reaction. Beryl and phenacite minerals were choosen in this research since they are opposite each other with respect to the helium contents. Both have beryllium in their compositon but beryl hold a large amount of helium while phenacite, in spite of having about three times more beryllium than beryl, do not hold the gas. (author)

  3. Mechanisms of beryl flotation: a literature review

    International Nuclear Information System (INIS)

    This paper shows a review about the investigations that have been done on the mechanisms of flotation of beryl and its dependence in relation to the presence of fluoride species. It is also analised the anionic flotation of the mineral and the effect of cations in the pulp of flotation. (author)

  4. Concentration of beryl by flotation: review of art state

    International Nuclear Information System (INIS)

    The concentration of beryl has been mainly investigated to develop a product as good as the ''hand-cobbed'' mineral used in the extrative metallurgy of beryllium. The purpose of this paper is to show a review of the concentration of beryl by cationic and anionic flotation depicting their principal aspects. (author)

  5. Optical absorption in irradiated natural beryl

    International Nuclear Information System (INIS)

    Three species of beryl irradiated with γ-rays of 60Co were studied by optical absorption. One became yellow and the other two Maxixe's blue. The effects of heat treatments were determined by the thermal isochronal decays of the optical absorption bands. Activation energies and frequency factor were obtained through the first order process kinetic model. Discussions lend us to assign for the UV band-edge the model of absorption by a hole center stabilized by a Fe2+ (substituting Al3+) ion in a neighbour oxygen. (Author)

  6. Study of the chemical stability of beryl and of the product of its mechanical activation against sulfuric acid

    International Nuclear Information System (INIS)

    Effect of the concentration of sulfuric acid used for beryl sulfatization, degree of beryl grinding, temperature and duration of beryl sulfatization, and other technological parameters of sulfuric acid decomposition on the extent of beryl recovery was studied. The results obtained made it possible to suggest a method for preparation of beryl concentrates for sulfatization. The method is based on a mechanochemical activation of this kind of raw materials and can serve as an alternative to the conventionally employed beryl activation techniques

  7. Effects of metallic cations in the beryl flotation

    International Nuclear Information System (INIS)

    The beryl zeta potential in microelectrophoretic cell is studied in the presence of neutral electrolyte, cations of calcium, magnesium and iron. The petroleum sulfonate is used how collector in Hallimond tube. Hydroxy complex of metallic cations seems activate the ore and precipitates of colloidal metallic hidroxies seems lower him when added to the mixture. (M.A.C.)

  8. Use of laser induced breakdown spectroscopy in the determination of gem provenance: beryls.

    Science.gov (United States)

    McManus, Catherine E; McMillan, Nancy J; Harmon, Russell S; Whitmore, Robert C; De Lucia, Frank C; Miziolek, Andrzej W

    2008-11-01

    The provenance of gem stones has been of interest to geologists, gemologists, archeologists, and historians for centuries. Laser induced breakdown spectroscopy (LIBS) provides a minimally destructive tool for recording the rich chemical signatures of gem beryls (aquamarine, goshenite, heliodor, and morganite). Broadband LIBS spectra of 39 beryl (Be(3)Al(2)Si(6)O(18)) specimens from 11 pegmatite mines in New Hampshire, Connecticut, and Maine (USA) are used to assess the potential of using principal component analysis of LIBS spectra to determine specimen provenance. Using this technique, beryls from the three beryl-bearing zones in the Palermo #1 pegmatite (New Hampshire) can be recognized. However, the compositional variation within this single mine is comparable to that in beryls from all three states. Thus, a very large database with detailed location metadata will be required to routinely determine gem beryl provenance. PMID:19122706

  9. Sliding Wear Response of Beryl Reinforced Aluminum Composite - A Factorial Design Approach

    Science.gov (United States)

    Bharat, V.; Durga Prasad, B.; Prabhakar, M. Bhovi; Venkateswarlu, K.

    2016-02-01

    Al-Beryl MMCs were successfully fabricated using powder metallurgy route. Processing conditions such as beryl content and particle size were varied and its influence on dry sliding wear response was studied. Effect of test parameters like applied load and sliding distance on wear performance of Al-Beryl MMCs were discussed detail. Sliding wear tests were conducted using a pin on disc machine based on the 24 (4 factors at 2 levels) factorial design. Analysis of variance (ANOVA) was performed to obtain the contribution of control parameters on wear rate. The present study shows that wear resistance of Al-beryl MMCs not only depends on the beryl content but also influenced by normal load, sliding distance and particle size. The results show that most significant variables affecting wear rate of Al - beryl MMCs are size of the beryl particles (22%), beryl content (19.60%), sliding distance (18.47%), and normal load (10.30%). The interaction effects of these parameters are less significant in influencing wear rate compared to the individual parameters. The correlation between sliding wear and its parameters was obtained by multiple regression analysis. Regression model developed in the present study can be successfully implemented to predict the wear response of Al-Beryl MMCs.

  10. Preparation of copper-beryllium alloys from Indian beryl

    International Nuclear Information System (INIS)

    The report presents the results of laboratory scale investigations on the preparation of copper-beryllium and aluminium-beryllium master alloys starting from Indian beryl and adopting the fluoride process. The flow-sheet involves : (1) conversion of the Be-values in beryl into water soluble sodium beryllium fluoride (2) preparation of beryllium hydroxide by alkali treatment of aqueous Na2BeF4 (3) conversion of Be(OH)2 to (NH4)2BeF4 by treatment with NH4HF2 (4) thermal decomposition of (NH4)2BeF4 to BeF2 and (5) magnesium reduction of BeF2 (with the addition of copper/aluminium) to obtain beryllium alloys. The method has been successfully employed for the preparation of Cu-Be master alloys containing about 8% Be and free of Mg on a 200 gm scale. An overall Be-recovery of about 80% has been achieved. Al-8% Be master alloys have also been prepared by this method. Toxicity and health hazards associated with Be are discussed and the steps taken to ensure safe handling of Be are described. (author)

  11. High-dose dosimetry of beta rays using blue beryl dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    Carmo, Lucas S. do, E-mail: lsatiro@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Watanabe, Shigueo; Bittencour, Jose F., E-mail: Lacifid@if.usp.br [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Instituto de Fisica. Departamento de Fisica Nuclear

    2015-07-01

    High dose radiation is widely used in industrial applications as sterilization of medical products, improvement of materials properties, color enhancement of jewelry stones, etc. The radiation dosimetry of high doses is quite important for these applications. In this work we have investigated the usage of blue beryl crystal also known as aquamarine in high dose dosimetry of beta rays. Some works have shown that silicate minerals exhibit a good Thermoluminescent response when irradiated up to 2000 kGy of gamma rays. Here, we have produced small beryl pellets of approximately 5 mm in diameter and 3 mm thickness to measure high doses of beta rays produced at an electron accelerator at IPEN. Twelve beryl dosimeters were made and six of them were irradiated from 10kGy up to 100 kGy. The technique used to create a calibration curve was the thermoluminescence using the glow peak at 310°C. (author)

  12. The surface preparation of beryl crystals for X-ray spectroscopy

    International Nuclear Information System (INIS)

    One of the few crystals available for X-ray spectroscopy in the 10 to 15 A band is natural beryl. Surface preparation of beryl crystals by etching in hydrofluric acid followed by polishing in X-30 syton is shown to bring the rocking curve widths (FWHM) as measured on a two-crystal spectrometer to the near perfect values of 5 arc sec at Cu Kα (1.54 A) and 3.3 arc min at Cu Lα (13.31 A). In addition the crystals peak reflectivity can be enhanced by a factor eight times that of flat and ground but otherwise untreated crystals. (author)

  13. EFFECT OF AGING ON MECHANICAL AND WEAR PROPERTIES OF BERYL PARTICULATE REINFORCED METAL MATRIX COMPOSITES

    Directory of Open Access Journals (Sweden)

    H. N. REDDAPPA

    2014-08-01

    Full Text Available This paper describes the study of effect of aging on mechanical and wear properties of ‘hot rolled’ Al6061-10% wt. of beryl particulate reinforced composites produced by stir casting have been examined. The result shows that hardness and tensile strength of ‘90% hot rolled and aged’ composites were increased by 10.28% and 3.78% as compared to ‘hot rolled’ composites respectively. The ‘hot rolled and aged’ composite shows significant decrease in specific wear rate when compared to that of ‘hot rolled’ composites.

  14. Hydrothermal growth of beryl single crystals and morphology of their singular faces

    International Nuclear Information System (INIS)

    The surface morphology of the best developed faces of emerald and red beryl monocrystals grown from high-temperature hydrothermal solutions has been studied by atomic force microscopy. The results attest to dislocation-mediated layer-by-layer growth of the faces. Using experimentally determined growth front profiles, the fractal dimensions DFp and DFa of the faces are evaluated to be 1.1-1.4. These values indicate that the surfaces studied have a fractal character and can be investigated using elements of fractal theory

  15. Lung function, biological monitoring, and biological effect monitoring of gemstone cutters exposed to beryls

    Science.gov (United States)

    Wegner, R.; Heinrich-Ramm, R.; Nowak, D.; Olma, K.; Poschadel, B.; Szadkowski, D.

    2000-01-01

    OBJECTIVES—Gemstone cutters are potentially exposed to various carcinogenic and fibrogenic metals such as chromium, nickel, aluminium, and beryllium, as well as to lead. Increased beryllium concentrations had been reported in the air of workplaces of beryl cutters in Idar-Oberstein, Germany. The aim of the survey was to study the excretion of beryllium in cutters and grinders with occupational exposure to beryls—for example, aquamarines and emeralds—to examine the prevalence of beryllium sensitisation with the beryllium lymphocyte transformation test (BeLT), to examine the prevalence of lung disease induced by beryllium, to describe the internal load of the respective metals relative to work process, and to screen for genotoxic effects in this particular profession.
METHODS—In a cross sectional investigation, 57 out of 100 gemstone cutters working in 12 factories in Idar-Oberstein with occupational exposure to beryls underwent medical examinations, a chest radiograph, lung function testing (spirometry, airway resistance with the interrupter technique), and biological monitoring, including measurements of aluminium, chromium, and nickel in urine as well as lead in blood. Beryllium in urine was measured with a newly developed direct electrothermal atomic absorption spectroscopy technique with a measurement limit of 0.06 µg/l. Also, cytogenetic tests (rates of micronuclei and sister chromatid exchange), and a BeLT were performed. Airborne concentrations of beryllium were measured in three factories. As no adequate local control group was available, the cutters were categorised into those with an exposure to beryls of >4 hours/week (group A) and ⩽4 hours/week (group B).
RESULTS—Clinical, radiological, or spirometric abnormalities indicating pneumoconiosis were detected in none of the gemstone cutters. Metal concentrations in biological material were far below the respective biological limit values, and beryllium in urine was only measurable in

  16. Characterization and application of tourmaline and beryl from Brazilian pegmatite in adsorption process with divalent metals

    Institute of Scientific and Technical Information of China (English)

    Denis L.Guerra; Silze P.Oliveira; Ricardo A.R.Silva; Victor Leidens; Adriano C.Batista

    2012-01-01

    In this study,the original tourmaline and beryl mineral samples have been collected from a Brazilian pegmatite.The objective of this study was to examine the adsorption behavior of Brazilian ciclosilicate sampies,towards divalent metals (Pb2+,Mn2+,and Zn2+) in ethanol solution has been studies by a batch technique.The ciclosilicate samples were characterized by elemental analysis,Fourier transform infrared spectroscopy,helium picnometry,mercury porosity,and nitrogen adsorption-desorption.The Langmuir expression for adsorption isotherm was applied in order to determine the adsorption capacity to form a monolayer and the constant related to the adsorption intensity.In aqueous solution there was a significant adsorption increase with the temperature and pronounced synergistic effects were observed.The maximum number of moles adsorbed was determined to be 12.48 and 11.49 mmol/g for systems Pb2+/beryl and Pb2+/tourmaline,respectively.The energetic effects caused by metal cations adsorption were determined through calorimetric titrations.Thermodynamics indicated the existence of favorable conditions for such Pb2+-,Mn2+-,and Zn2+-OH interactions.

  17. EFFECT OF SOLUTIONIZING ON DRY SLIDING WEAR OF AL2024-BERYL METAL MATRIX COMPOSITE

    Directory of Open Access Journals (Sweden)

    Abdul Sharief

    2012-12-01

    Full Text Available In the present investigation, Al2024–Beryl particulate composites were fabricated by stir casting by varying the weight percentage of beryl particulates from 0 wt% to 10 wt% in steps of 2 wt%. The cast Al2024 alloy and its composites have been subjected to solutionizing treatment at a temperature of 495°C for 2 hrs, followed by ice quenching. Microstructural studies were carried out to determine the nature of the structure. The Brinell hardness test was conducted on both the Al2024 alloy and its composites before and after solutionizing. Pin-on disc wear tests were conducted to examine the wear behavior of the Al2024 alloy and its composites. Sliding wear tests were conducted at various applied loads, sliding velocities and sliding distances. The results reveal that the wear rate of the composites is lower than that of the matrix alloy. The wear rate increased with an increasing applied load and sliding distance, and decreased with increasing sliding velocity.

  18. A new approach for the beryl mineral decomposition: elemental characterisation using ICP-AES and FAAS

    International Nuclear Information System (INIS)

    A new approach for the beryl mineral sample decomposition and solution preparation method suitable for the elemental analysis using ICP-AES and FAAS is described. For the complete sample decomposition four different decomposition procedures are employed such as with (i) ammonium bi-fluoride alone (ii) a mixture of ammonium bi-fluoride and ammonium sulphate (iii) powdered mixture of NaF and KHF2 in 1: 3 ratio, and (iv) acid digestion treatment using hydrofluoric acid and nitric acid mixture, and the residue fused with a powdered mixture NaF and KHF2. Elements like Be, Al, Fe, Mn, Ti, Cr, Ca, Mg, and Nb are determined by ICP-AES and Na, K, Rb and Cs are determined by FAAS method. Fusion with 2g ammonium bifluoride flux alone is sufficient for the complete decomposition of 0.400 gram sample. The values obtained by this decomposition procedure are agreed well with the reported method. Accuracy of the proposed method was checked by analyzing synthetic samples prepared in the laboratory by mixing high purity oxides having a chemical composition similar to natural beryl mineral. It indicates that the accuracy of the method is very good, and the reproducibility is characterized by the RSD 1 to 4% for the elements studied. (author)

  19. Speciation and diffusion profiles of H2O in water-poor beryl: comparison with cordierite

    Science.gov (United States)

    Della Ventura, G.; Radica, F.; Bellatreccia, F.; Freda, C.; Cestelli Guidi, M.

    2015-10-01

    This paper reports on water speciation and diffusion in synthetic beryl samples treated in CO2-rich atmosphere, at 700 MPa and 700 and 800 °C, respectively. The study has been conducted by means of polarized FTIR (Fourier transform infrared) integrated with FPA (focal plane array) imaging. As expected, the infrared spectra show the presence of CO2 but also of minor H2O interpreted as resulting from moisture present in the starting materials used for the experiments. FPA-FTIR images show that H2O diffuses into the beryl matrix along the structural channels oriented parallel to [001]. Spectra collected along profiles parallel to the c-axis show subtle changes as a function of the distance from the crystal edge; these changes can be correlated to a progressive change in the H2O coordination environment in the channel, as a response to the varying H2O/alkali ratio. In particular, the data show that when 2H2O > Na+ apfu (atoms per formula unit), H2O can assume both type I and type II orientation; in the latter case, each Na cation coordinates two H2O[II] molecules (doubly coordinated H2O). If 2H2O coefficients and activation energies have been also determined for both types of water molecules.

  20. Structure Refinement of Cs-rich Na-Li Beryl and Analysis of Its Typomorphic Characteristics of Configurations

    Institute of Scientific and Technical Information of China (English)

    LIU Yan; DENG Jun; LI Guowu; SHI Guanghai

    2007-01-01

    The tabular beryl found in Huya Country, Sichuan Province is a rare and special member among beryls. Chemical analysis reveals that the beryl is a new type of Cs-rich Na-Li beryl, and the content of alkalis (Li2O, Na2O, K2O, Rb2O, Cs2O) is up to 2.41%. The CCD system on the SMART APEX four circle single crystal diffractometer was used in this experiment to determine the structure of the sample accurately. The beryl belongs to the hexagonal system; its space group is P6/mcc. The dimensions of the unit cell are as follows: a = 0.91961(3) nm, c = 0.91969(7) nm, c/a= 1.0000, V= 0.67357nm3, γ = 120°, a = 90°, β = 90°. The accurate atomic coordinates of alkali metal ions and other crystallographic parameters are also obtained: Z = 2, the calculated density D = 2.754 g/cm3 and final R ( Ⅰ> 2 σ (Ⅰ))= 0.046 for 5597 reflections. The crystal structure was described by coordination polyhedron. Based on the data gained, a three-dimensional graph of the crystal structure of tabular beryl was made with the ATOMS 6.0 software. The refinement of crystal structure indicates that there are two main reasons for the cause of the tabular configuration: (1) The substitution of Be by Li into the tetrahedral framework weakened the stacked six-sided rings [Si6O1s]12- of the tetrahedral Si; (2) Alkalis (mainly Na and Cs) are too large to substitute in four-fold or six-fold coordination within the structure and are accommodated in the vacant channel. The accommodation of these alkalis strengthened the structure of six-sided rings of the tetrahedral Si. And other alkali metal ions and free volatile molecules such as H2O and CO2 occupy variable positions in the channel. The equation of the electrovalence is Li++Na+→Be2+. According to structural and compositional differences, the monoclinic crystal of tabular beryl is considered to be a new member of the beryl group. Chemical constraints of the environment, namely, the bulk-rock chemistry and the fluid-phase composition and

  1. Structural features and isomorphous substitutions in chromium- and magnesium-containing beryls and chromium-containing beryllian indialite grown by the flux method

    International Nuclear Information System (INIS)

    Beryls and beryllian indialite {the general formula MVI2T(2)IV3T(1)IV6O18} synthesized in magnesium-containing flux systems saturated with chromium are investigated using X-ray diffraction. The isovalent schemes of the isomorphous incorporation of chromium into Moctahedra of these compounds and the simultaneously realized heterovalent schemes with the participation of other components are revealed from the occupancies of the positions. It is demonstrated that an increase in the average bond lengths in the M positions leads predominantly to an increase in the parameter α. In the beryllian indialites, the T(1) tetrahedra are substantially closer to perfect tetrahedra, the T(2) tetrahedra are distorted to a lesser extent, and the M octahedra are distorted to a greater extent than those in beryls. The structural indications of the ability of compounds with a beryl structure to congruently melt are distinguished.

  2. Spectroscopic and bond-topological investigation of interstitial volatiles in beryl from Slovakia

    Science.gov (United States)

    Fridrichová, Jana; Bačík, Peter; Bizovská, Valéria; Libowitzky, Eugen; Škoda, Radek; Uher, Pavel; Ozdín, Daniel; Števko, Martin

    2016-03-01

    Nine beryl samples from Western Carpathians, Slovakia, were investigated by infrared and Raman spectroscopy and differential thermal analysis. Two types of water H2O I and H2O II were detected. Infrared spectroscopy proved the presence of water type I and II in the presence of alkali cations with several bands: (1) symmetric stretching vibration—ν1; (2) antisymmetric stretching mode—ν3; (3) bending vibration—ν2. The presence of singly and doubly coordinated type II water (IIs and IId) was confirmed by single-crystal IR spectroscopy. From Raman spectra a band at 3606 cm-1 was assigned to ν1 of water type I and the range of 3597-3600 cm-1 to water type II. The presence of doubly coordinating water indicates a relatively highly hydrated environment with the presence of alkali ions including Na as the dominant cation coordinated by H2O II. CO2 bands were detected only by single-crystal IR spectroscopy. Thermal analysis proved total water loss in the range of 1.4-2.0 wt% and three main dehydration events. Based on the study of bond-topological arrangements two molecules of H2O IId are each bound with two H···O1 bonds and one Na-OW bond with an angular distortion, and by releasing one H2O molecule more stable H2O IIs is produced. The H2O I molecule is bound only by two equivalent hydrogen bonds. The H2O IIs molecule with a Na-OW bond strength of 0.28 vu and two H···O1 bonds of 0.14 vu without any forced angular distortion is the most stable of all.

  3. Synthesis and study of physicochemical properties of Be3Al2[Si6O18] beryl monocrystals activated by neodymium and chromium ions

    International Nuclear Information System (INIS)

    Using the results of spectral and luminescent studies, the principal possibility of the synthesis of single crystals of beryl activated by Nd3+ and Cr3+ by solution-melt method is shown. Neodymium and chromium are introduced as oxides in an amount of 2wt.% and 0.5 wt.%, respectively. The crystals prepared measure 0.1x0.2 mm, they are a light green colour, hexagonal prisms in shape. It is found from the results of X-ray phase analysis that the single crystals prepared fully meet the hexagonal structure of beryl

  4. Storage of Nitrogen in the Cyclosilicates Beryl and Cordierite: Nitrogen Cycling, Isotope Fractionation, and Fluid-Rock Interactions

    Science.gov (United States)

    Lazzeri, K. E.; Bebout, G. E.; Idleman, B. D.; Geiger, C. A.; Li, L.

    2011-12-01

    The N isotope system shows potential for tracing the transfer of volatiles among Earth's major reservoirs, including the transfer of organic N into solid inorganic phases. This work explores the potential for the storage of N (i.e., N2 and possibly as ammonium) in various microporous minerals (pores or channels), specifically the cyclosilicates beryl and cordierite (see early work on beryl by Scalan, 1958, dissertation, Univ. Arkansas). Isotopic analyses of the N2 residing in these phases could help elucidate fluid-rock interactions, potentially contributing information regarding fluid-mineral fractionation, and provide records of past biological processes (see Palya et al., 2011, Chem. Geol.). We are investigating the N release from beryl crystals of different size separates by using various heating regimes. Samples are first examined petrographically to determine equilibrium mineral assemblages (based on textures of the coexisting phases) and to identify possible mica (or other mineral) inclusions that could contaminate the N analyses. Analyses of one beryl sample from New England, USA, yielded very similar N concentrations and δ15Nair (40 ppm N; +5%) when tested over a wide range of grain sizes (0.25 to 1.00 mm), extraction temperatures (1050-1100°C), and durations of heating (3-5 hours at maximum T), which is consistent with complete extraction of the N2 from the channels of beryl. Shift to higher N and δ15N concentrations, in some analyses, can be attributed to very small amounts of mica as inclusions (observed by SEM) not removed by sieving and hand-picking. Preliminary work on cordierite has concentrated on several samples of iolite (gemstone variety of cordierite)-bearing, chlorite-muscovite schist from Connecticut, USA. For these rock samples, mica-rich matrices contain up to 350 ppm N with δ15Nair near +3.5%, whereas the iolite grains contain little or no measurable N. This contrasts with the observation by Palya et al. (2011) that cordierites in

  5. Vibrational states of a water molecule in a nano-cavity of beryl crystal lattice

    International Nuclear Information System (INIS)

    Low-energy excitations of a single water molecule are studied when confined within a nano-size cavity formed by the ionic crystal lattice. Optical spectra are measured of manganese doped beryl single crystal Mn:Be3Al2Si6O18, that contains water molecules individually isolated in 0.51 nm diameter voids within the crystal lattice. Two types of orientation are distinguished: water-I molecules have their dipole moments aligned perpendicular to the c axis and dipole moments of water-II molecules are parallel to the c-axis. The optical conductivity σ(ν) and permittivity ε′(ν) spectra are recorded in terahertz and infrared ranges, at frequencies from several wavenumbers up to ν = 7000 cm−1, at temperatures 5–300 K and for two polarizations, when the electric vector E of the radiation is parallel and perpendicular to the c-axis. Comparative experiments on as-grown and on dehydrated samples allow to identify the spectra of σ(ν) and ε′(ν) caused exclusively by water molecules. In the infrared range, well-known internal modes ν1, ν2, and ν3 of the H2O molecule are observed for both polarizations, indicating the presence of water-I and water-II molecules in the crystal. Spectra recorded below 1000 cm−1 reveal a rich set of highly anisotropic features in the low-energy response of H2O molecule in a crystalline nano-cavity. While for E∥c only two absorption peaks are detected, at ∼90 cm−1 and ∼160 cm−1, several absorption bands are discovered for E⊥c, each consisting of narrower resonances. The bands are assigned to librational (400–500 cm−1) and translational (150–200 cm−1) vibrations of water-I molecule that is weakly coupled to the nano-cavity “walls.” A model is presented that explains the “fine structure” of the bands by a splitting of the energy levels due to quantum tunneling between the minima in a six-well potential relief felt by a molecule within the cavity

  6. Neutron activation analysis for some nonstoichiometric constituents in a large number of natural and synthetic beryl samples

    International Nuclear Information System (INIS)

    About 100 natural beryls from very different locations were analyzed. An appreciable content of all five alkali metals was present, so that determination with a good precision was an important crystalochemical as well as geochemical problem. The trace amounts of Cr, As, Sc, Mn, Eu, and Dy in some natural samples, as well as Co, Ni, Fe, Mo, Sc, Cs and Na were measured in a gamma-spectrometric arrangement with a 500-channel pulse height analyzer, without chemical treatment (i.e., in a nondestructive NAA procedure). The results obtained were partly controlled and compared by emission spectrography, flame spectrometry, and atomic absorption spectrometry, in order to determine the general reliability, as well as precision and accuracy in various analytical procedures and different samples

  7. FTIR-spectroscopic measurements of beryls of various sources and the geological mineralogical and gemmological characterization of diamonds of the Espinhago-range (Minas Gerais, Brazil)

    International Nuclear Information System (INIS)

    In this work international material of beryl was analyzed by FTIR-spectroscopy, electron microprobe, analytical scanning microscopy, moisture evolution analyzer and fluorine sensitive electrode. The FTIR-spectroscopic measurements and the determination of analytical water content reveal a logarithmic correlation between the beryl water content and the intensity of the H2O-combination band at 5275 cm-1, using unpolarized IR-light. In addition, the intensities of the 3990 - 3970 cm-1,-, 3234 cm-1 and 3345 cm-1-bands, measured with polarized IR-light parallel to the c-axis, are linearly correlated to the content of the alkali metals. Probably these bands correspond to fundamental (1st overtone of H2O-II/3234 cm-1- and 3345 cm-1) and combination (alkaliO-H...OH2-II/ 3990 - 3970 cm-1) modes of bending vibrations. Beryl was deuterated at various temperature. No absorption were detected in the region at around 2390 cm-1, 2470 cm-1 and 2940 cm-1, which would prove an assignment related to the present of hydrogen. If alkali-hydroxide grouping in beryl-channel-positions is indeuterable, the model of fundamental and combination modes seems to be valid. The band at 3990 - 3970 cm-1 can also be assigned to the combination mode of alkali-oxygen (alkali (6),(12)-O-bonds) vibrations and the normal modes of the H2O- II -molecule. The three integral absorption coefficients - α5267 (H2O-II)t α5275 (H2O-I) and α2358 (CO2) - were used to subdivide the beryls into groups. The Espinhago-Diamond-Province reflects an interesting geologic history from Precambrian placer- to recent alluvial deposits. Mineralogical and gemmological features, in combination with geological aspects reflect the many reworking processes which affected Espinhago diamonds in time and space: the characteristics of diamond populations in their specific geologic environment represent the natural selection, which eliminated stones of low quality during geologic history. (author)

  8. Geologic and geochemical features of the volatile-rich ore fluid and its tracing and dating in the Xuebaoding Beryl-Scheelite Vein Deposit,China

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Laser Raman spectrochemical analysis on single inclusion reveals that multi-phase fluid inclusions exist in the Xuebaoding Beryl-Scheelite Vein Deposit.Besides the solid daughter mineral,there are vapor CO2,liquid CO2,water-deficient CO2 and salt water solution from its center to the border.A close study on the fluid inclusion components and carbon,oxygen,helium and argon isotope tracing and dating suggests that the volatile-rich ore fluid might derive from postmagmatic fluid and rare element enrichment is the result of the mixture of the plutonic alkali granite with crustal material.

  9. Geologic and geochemical features of the volatile-rich ore fluid and its tracing and dating in the Xuebaoding Beryl-Scheelite Vein Deposit, China

    Institute of Scientific and Technical Information of China (English)

    曹志敏; 任建国; 郑建斌; 徐仕进; 李佑国; 王汝成; T.SHOJ; H.KANEDA; S.KABAYASHI

    2002-01-01

    Laser Raman spectrochemical analysis on single inclusion reveals that multi-phase fluid inclusions exist in the Xuebaoding Beryl- Scheelite Vein Deposit. Besides the solid daughter mineral, there are vapor CO2, liquid CO2, water-deficient CO2 and salt water solution from its center to the border. A close study on the fluid inclusion components and carbon, oxygen, helium and argon isotope tracing and dating suggests that the volatile-rich ore fluid might derive from postmagmatic fluid and rare element enrichment is the result of the mixture of the plutonic alkali granite with crustal material.

  10. Numerical integration method applied to the study of atomic hydrogen in a-Si: (H,O,N) and natural beryl decay kinetics

    International Nuclear Information System (INIS)

    A method of data processing was developed and applied to the study of decay kinetics of interstitial atomic hydrogen (H0i)1 in X-irradiated a-Si:(H,O,N)2 and natural beryl. A system of differential kinetic equations was constructed considering multiple possible reactions. the solutions were evaluated by Runge-Kutta's method of numerical integration. It was assumed that the H0i was produced by radiolytic irradiation of R-H type molecules and trapped at interstitial sites of both materials. The heating releases the H0 which quickly is either retrapped, recombined with R-radical left in the matrix or combined with other H0 atoms forming H2 molecules. The parameters related to untrapping and recombination processes were found to obey Arrhenius law. On the other hand, the retrapping and H-2 formation parameters were fit to a function proportional to T1/2 - T1/2o, where at T0 they vanish. (author)

  11. Heat capacities and thermodynamic functions for beryl, Be3Al2Si6O18, phenakite, Be2SiO4, euclase, BeAlSiO4(OH), bertrandite, Be4Si2O7(OH)2, and chrysoberyl, BeAl2O4.

    Science.gov (United States)

    Hemingway, B.S.; Barton, M.D.; Robie, R.A.; Haselton, H.T., Jr.

    1986-01-01

    The heat capacities of beryl, phenakite, euclase and bertrandite have been measured between approx 5 and 800 K by combined quasi-adiabatic cryogenic calorimetry and differential scanning calorimetry. The heat capacities of chrysoberyl have been measured from 340 to 800 K. The resulting data have been combined with solution and phase-equilibrium experimental data and simultaneously adjusted using the programme PHAS20 to provide an internally consistent set of thermodynamic properties for several important beryllium phases. The experimental heat capacities and tables of derived thermodynamic properties are presented.-J.A.Z.

  12. Parcels and Land Ownership, Beryl Junction parcels, Published in 2006, 1:24000 (1in=2000ft) scale, Iron County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Parcels and Land Ownership dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2006. It is described as...

  13. Ferroindialite (Fe2+,Mg)2Al4Si5O18, a new beryl-group mineral from the Eifel volcanic region, Germany

    Science.gov (United States)

    Chukanov, N. V.; Aksenov, S. M.; Pekov, I. V.; Ternes, B.; Schüller, W.; Belakovskiy, D. I.; Van, K. V.; Blass, G.

    2014-12-01

    A new mineral, ferroindialite, a Fe2+-dominant analog of indialite, has been found in a pyrometamorphosed xenolith of pelitic rock hosted in alkaline basalts. Associated minerals are phlogopite, sanidine, sillimanite, pyroxenes of the enstatite-ferrosilite series, wagnerite, fluorapatite, tridymite, zircon and almandine. Ferroindialite forms brown-purple to gray with a violet-blue tint short prismatic or thick tabular hexagonal crystals up to 1.5 mm in size. The new mineral is brittle, with a Mohs' hardness of 7. Cleavage is not observed. D meas = 2.66(1), D calc = 2.667 g/cm3. IR spectrum shows neither H2O nor OH groups. Ferroindialite is anomalously biaxial (-), α = 1.539(2), β = 1.552(2), γ = 1.554(2), 2 V meas = 30(10)°. The mineral is weakly pleochroic, ranging from colorless on X to pale violet on Z. Dispersion is weak, r < v. The chemical composition (electron microprobe, mean of five point analyses, wt %) is as follows: 0.14 Na2O, 0.46 K2O, 4.95 MgO, 1.13 MnO, 12.66 FeO, 2.64 Fe2O3, 30.45 Al2O3, 47.22 SiO2, total is 99.65. The distribution of total iron content between Fe2+ and Fe3+ was carried out according to structural data. The empirical formula of ferroindialite is: (K0.06Na0.03)(Fe{1.12/2+}Mg0.78Mn0.10)Σ2.00(Al3.79Fe{0.21/3+})Σ4.00Si4.98O18. The simplified formula is: (Fe2+,Mg)2Al4Si5O18. The crystal structure has been refined on a single crystal, R = 0.049. Ferroindialite is hexagonal, space group P6/ mcc; a = 9.8759(3), c = 9.3102(3) Å, V = 786.40(3) Å3, Z = 2. The strongest lines in the X-ray powder diffraction pattern [ d, Å ( I, %) ( hkl)] are: 8.59 (100) (100), 4.094 (27) (102), 3.390 (35) (112), 3.147 (19) (202), 3.055 (31) (211), 2.657 (12) (212), 1.695 (9) (224). The type specimen of ferroindialite is deposited in the Fersman Mineralogical Museum, Russian Academy of Sciences, Moscow, registration number 4400/1.

  14. THz–IR spectroscopy of single H.sub.2./sub.O molecules confined in nanocage of beryl crystal lattice

    Czech Academy of Sciences Publication Activity Database

    Gorshunov, B. P.; Zhukova, E.S.; Torgashev, V. I.; Motovilova, E.A.; Lebedev, V.V.; Prokhorov, A. S.; Shakurov, G.S.; Kremer, R. K.; Uskov, V.V.; Pestrjakov, E.V.; Thomas, V.G.; Fursenko, D.A.; Kadlec, Christelle; Kadlec, Filip; Dressel, M.

    2014-01-01

    Roč. 87, 10-11 (2014), s. 966-972. ISSN 0141-1594 R&D Projects: GA ČR(CZ) GA14-25639S Institutional support: RVO:68378271 Keywords : terahertz spectroscopy * nano-confined water molecule Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.954, year: 2014

  15. TEN RILLINGTON PLACE AND THE CHANGING POLITICS OF ABORTION IN MODERN BRITAIN*

    OpenAIRE

    Jones, Emma L.; Pemberton, Neil

    2014-01-01

    This article addresses the social, cultural, and political history of backstreet abortion in post-war Britain, focusing on the murders of Beryl Evans and her daughter Geraldine, at Ten Rillington Place in 1949. It shows how the commonplace connection of John Christie to abortion and Beryl Evan's death was not a given in the wider public, legal, political, and forensic imagination of the time, reflecting the multi-layered and shifting meanings of abortion from the date of the original trials i...

  16. Physicochemical characteristics of aerosol particles generated during the milling of beryllium silicate ores: implications for risk assessment.

    Science.gov (United States)

    Stefaniak, Aleksandr B; Chipera, Steve J; Day, Gregory A; Sabey, Phil; Dickerson, Robert M; Sbarra, Deborah C; Duling, Mathew G; Lawrence, Robert B; Stanton, Marcia L; Scripsick, Ronald C

    2008-01-01

    Inhalation of beryllium dusts generated during milling of ores and cutting of beryl-containing gemstones is associated with development of beryllium sensitization and low prevalence of chronic beryllium disease (CBD). Inhalation of beryllium aerosols generated during primary beryllium production and machining of the metal, alloys, and ceramics are associated with sensitization and high rates of CBD, despite similar airborne beryllium mass concentrations among these industries. Understanding the physicochemical properties of exposure aerosols may help to understand the differential immunopathologic mechanisms of sensitization and CBD and lead to more biologically relevant exposure standards. Properties of aerosols generated during the industrial milling of bertrandite and beryl ores were evaluated. Airborne beryllium mass concentrations among work areas ranged from 0.001 microg/m(3) (beryl ore grinding) to 2.1 microg/m(3) (beryl ore crushing). Respirable mass fractions of airborne beryllium-containing particles were 80% in high-energy input areas (beryl melting, beryl grinding). Particle specific surface area decreased with processing from feedstock ores to drumming final product beryllium hydroxide. Among work areas, beryllium was identified in three crystalline forms: beryl, poorly crystalline beryllium oxide, and beryllium hydroxide. In comparison to aerosols generated by high-CBD risk primary production processes, aerosol particles encountered during milling had similar mass concentrations, generally lower number concentrations and surface area, and contained no identifiable highly crystalline beryllium oxide. One possible explanation for the apparent low prevalence of CBD among workers exposed to beryllium mineral dusts may be that characteristics of the exposure material do not contribute to the development of lung burdens sufficient for progression from sensitization to CBD. In comparison to high-CBD risk exposures where the chemical nature of aerosol

  17. Thermal Induced Processes in Laminar System of Stainless Steel - Beryllium

    International Nuclear Information System (INIS)

    The paper reports on investigation of the laminar system 'stainless steel 12Cr18Ni10Ti - Be' at thermal treatment. There have been determined sequences of phase transformations along with relative amount of iron-containing phases in the samples subjected to thermal beryllization. It has been revealed that thermal beryllization of stainless steel thin foils results in γ→α transformation and formation of the beryllides NiBe and FeBe2. It has also been revealed that direct γ→α- and reverse α→γ-transformations are accompanied by, correspondingly, formation and decomposition of the beryllide NiBe. It is shown that distribution of the formed phases within sample bulk is defined by local concentration of beryllium. Based on obtained experimental data there is proposed a physical model of phase transformations in stainless steel at thermal beryllization.

  18. Beryllium development programme in India

    International Nuclear Information System (INIS)

    India has fairly large deposits of beryl. The requirement of beryllium and copper-beryllium alloys in space and electronic industries has provided the incentive for the setting up of an indigenous base for the development of beryllium process metallurgy. The paper presents the developmental work carried out, in the Metallurgy Division of the Bhabha Atomic Research Centre, on the preparation of beryllium metal and its alloys starting from Indian beryl. A laboratory facility incorporating essential precautionary measures has been set up for the safe handling of beryllium and its compounds. Based on the laboratory investigations a flow-sheet suitable to Indian conditions has been developed. The flow-sheet involves preparation of anhydrous beryllium fluoride from beryl through the silico-fluoride route, magnesiothermic reduction of beryllium fluoride for the production of beryllium metal or its master alloy with copper or aluminium, and fabrication of beryllium metal. (author)

  19. Multi-element analysis of emeralds and associated rocks by k{sub 0} neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Acharya, R.N.; Mondal, R.K.; Burte, P.P.; Nair, A.G.C.; Reddy, N.B.Y.; Reddy, L.K.; Reddy, A.V.R.; Manohar, S.B

    2000-12-15

    Multi-element analysis was carried out in natural emeralds, their associated rocks and one sample of beryl obtained from Rajasthan, India. The concentrations of 21 elements were assayed by Instrumental Neutron Activation Analysis using the k{sub 0} method (k{sub 0} INAA method) and high-resolution gamma ray spectrometry. The data reveal the segregation of some elements from associated (trapped and host) rocks to the mineral beryl forming the gemstones. A reference rock standard of the US Geological Survey (USGS BCR-1) was also analysed as a control of the method.

  20. Multi-element analysis of emeralds and associated rocks by k(o) neutron activation analysis

    Science.gov (United States)

    Acharya; Mondal; Burte; Nair; Reddy; Reddy; Reddy; Manohar

    2000-12-01

    Multi-element analysis was carried out in natural emeralds, their associated rocks and one sample of beryl obtained from Rajasthan, India. The concentrations of 21 elements were assayed by Instrumental Neutron Activation Analysis using the k0 method (k0 INAA method) and high-resolution gamma ray spectrometry. The data reveal the segregation of some elements from associated (trapped and host) rocks to the mineral beryl forming the gemstones. A reference rock standard of the US Geological Survey (USGS BCR-1) was also analysed as a control of the method. PMID:11077961

  1. Experience with piston and piston-rod seals for high-pressure reciprocating compressors injecting natural gas on North Sea production platforms

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, R.S.

    1983-12-01

    The need to restrict flaring of associated natural gas has emphasized the importance of reliability of high-pressure reinjection compressors installed on certain North Sea platforms. This paper reviews the contribution made by the development of piston and rod seals used on injection compressors, with reference to three important fields: Beryl, Statfjord, and Thistle.

  2. Experience with piston and piston rod seals for high pressure reciprocating compressors injecting natural gas on North Sea production platforms

    Energy Technology Data Exchange (ETDEWEB)

    Wison, R.S.

    1981-01-01

    The need to restrict flaring of associated natural gas has emphasized the importance of reliability of high-pressure reinjection compressors installed on certain North Sea platforms. This work reviews the contribution made by the development of piston and rod seals used on injection compressors, with reference to 3 important fields: Beryl, Statfjord, and Thistle.

  3. Quantum tunneling and vibrational dynamics of ultra-confined water

    Science.gov (United States)

    Kolesnikov, Alexander I.; Anovitz, Lawrence M.; Ehlers, Georg; Mamontov, Eugene; Podlesnyak, Andrey; Prisk, Timothy R.; Seel, Andrew; Reiter, George F.

    2015-03-01

    Vibrational dynamics of ultra-confined water in single crystals beryl, the structure of which contains ~ 5 Å diameter channels along the c-axis was studied with inelastic (INS), quasi-elastic (QENS) and deep inelastic (DINS) neutron scattering. The results reveal significantly anisotropic dynamical behavior of confined water, and show that effective potential experienced by water perpendicular to the channels is significantly softer than along them. The observed 7 peaks in the INS spectra (at energies 0.25 to 15 meV), based on their temperature and momentum transfer dependences, are explained by transitions between the split ground states of water in beryl due to water quantum tunneling between the 6-fold equivalent positions across the channels. DINS study of beryl at T=4.3 K shows narrow, anisotropic water proton momentum distribution with corresponding kinetic energy, EK=95 meV, which is much less than was previously observed in bulk water (~150 meV). We believe that the exceptionally small EK in beryl is a result of water quantum tunneling ∖ delocalization in the nanometer size confinement and weak water-cage interaction. The neutron experiment at ORNL was sponsored by the Sci. User Facilities Div., BES, U.S. DOE. This research was sponsored by the Div. Chemical Sci, Geosciences, and Biosciences, BES, U.S. DOE. The STFC RAL is thanked for access to ISIS neutron facilities.

  4. 40 CFR 421.153 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Science.gov (United States)

    2010-07-01

    ... provided in 40 CFR 125.30 through 125.32, any existing point source subject to this subpart shall achieve....000 0.000 (k) Beryl Ore Gangue Dewatering. BAT Limitations for the Primary Beryllium Subcategory... Gangue Dewatering. BAT Limitations for the Primary Beryllium Subcategory Pollutant or pollutant...

  5. 40 CFR 421.156 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... § 421.156 Pretreatment standards for new sources. Except as provided in 40 CFR 403.7, any new source... 40 CFR part 403 and achieve the following pretreatment standards for new sources. The mass of....000 0.000 Ammonia (as N) 0.000 0.000 Fluoride 0.000 0.000 (k) Beryl Ore Gangue Dewatering. PSNS...

  6. Test of colouring effect in gemstones by some sorts of radiation

    International Nuclear Information System (INIS)

    Some kinds of gemstones like topaz, beryl, corindon, marion, etc. were irradiated by thermal neutrons, 14 MeV-neutrons, mixed neutron-gamma field and Bremsstrahlung for testing colouring effect. Some typical nuclear reactions were studied. The kinetic function method was used for analyzing complex photopeaks. A possible formation of smokiness quartz in the nature was discussed. (author). 5 refs, 1 tab

  7. The growth mechanism and morphology of hydrothermally grown oxide compounds: fractal approach

    International Nuclear Information System (INIS)

    Single crystals of Fe2O3 (haematite), Be3Al2Si6O18 (beryl) have been grown on seeds from hydrothermal solutions. Optical microscopy and AFM have been used for the study of the growth morphology of atomically smooth faces of single crystals as well as of the surfaces growing in accordance with the regeneration growth mechanism. Profiles of the crystallization front have been obtained for different directions of crystallization. Their analysis has shown that the growth morphology may be numerically characterized using the elements of fractal theory. The calculated values of the fractal dimensions are different for layer-by-layer growth and regeneration growth. For beryl single crystals, fractal analysis of the growth surface has been carried out and numerical fractal characteristics have been obtained using the area-perimeter method

  8. The growth mechanism and morphology of hydrothermally grown oxide compounds: fractal approach

    Science.gov (United States)

    Demianets, L. N.; Ivanov-Schitz, A. K.

    2004-04-01

    Single crystals of Fe2O3 (haematite), Be3Al2Si6O18 (beryl) have been grown on seeds from hydrothermal solutions. Optical microscopy and AFM have been used for the study of the growth morphology of atomically smooth faces of single crystals as well as of the surfaces growing in accordance with the regeneration growth mechanism. Profiles of the crystallization front have been obtained for different directions of crystallization. Their analysis has shown that the growth morphology may be numerically characterized using the elements of fractal theory. The calculated values of the fractal dimensions are different for layer-by-layer growth and regeneration growth. For beryl single crystals, fractal analysis of the growth surface has been carried out and numerical fractal characteristics have been obtained using the area-perimeter method.

  9. Single Crystals Grown Under Unconstrained Conditions

    Science.gov (United States)

    Sunagawa, Ichiro

    Based on detailed investigations on morphology (evolution and variation in external forms), surface microtopography of crystal faces (spirals and etch figures), internal morphology (growth sectors, growth banding and associated impurity partitioning) and perfection (dislocations and other lattice defects) in single crystals, we can deduce how and by what mechanism the crystal grew and experienced fluctuation in growth parameters through its growth and post-growth history under unconstrained condition. The information is useful not only in finding appropriate way to growing highly perfect and homogeneous single crystals, but also in deciphering letters sent from the depth of the Earth and the Space. It is also useful in discriminating synthetic from natural gemstones. In this chapter, available methods to obtain molecular information are briefly summarized, and actual examples to demonstrate the importance of this type of investigations are selected from both natural minerals (diamond, quartz, hematite, corundum, beryl, phlogopite) and synthetic crystals (SiC, diamond, corundum, beryl).

  10. Gemstones

    Science.gov (United States)

    Olson, D.W.

    2006-01-01

    During 2005, the estimated value of natural gemstones produced from US deposits was $13.9 million. Production included agates, amber, beryl, coral, garnet, jade, jasper, opal, pearl, quartz, sapphire, shell, topaz, tourmaline, and torquoise among others. For the year, the US gemstone trade with all countries and territories exceeded $26 billion. There are indication that there may be continued growth in the US diamond and jewelry markets in 2006.

  11. Doppler Radar and Lightning Network Observations of a Severe Outbreak of Tropical Cyclone Tornadoes

    Science.gov (United States)

    Mccaul, Eugene W., Jr.; Buechler, Dennis E.; Goodman, Steven J.; Cammarata, Michael

    2004-01-01

    Data from a single Weather Surveillance Radar-1988 Doppler (WSR-88D) and the National Lightning Detection Network are used to examine the characteristics of the convective storms that produced a severe tornado outbreak, including three tornadoes that reached F3 intensity, within Tropical Storm Beryl s remnants on 16 August 1994. Comparison of the radar data with reports of tornadoes suggests that only 13 cells produced the 29 tornadoes that were documented in Georgia and the Carolinas on that date. Six of these cells spawned multiple tornadoes, and the radar data confirm the presence of miniature supercells. One of the cells was identifiable on radar for 11 h. spawning tornadoes over a time period spanning approximately 6.5 h. Several other tornadic cells also exhibited great longevity, with cell lifetimes longer than ever previously documented in a landfalling tropical cyclone (TC) tornado event. This event is easily the most intense TC tornado outbreak yet documented with WSR-88Ds. Time-height analyses of the three strongest tornadic supercells are presented in order to document storm kinematic structure and to show how these storms appear at different ranges from a WSR-88D. In addition, cloud-to-ground (CG) lightning data are examined in Beryl s remnants. Although the tornadic cells were responsible for most of Beryl's CG lightning, their flash rates were only weak to moderate, and in all the tornadic storms the lightning flashes were almost entirely negative in polarity. A few of the single-tornado storms produced no detectable CG lightning at all. There is evidence that CG lightning rates decreased during the tornadoes, compared to 30-min periods before the tornadoes. A number of the storms spawned tornadoes just after producing their final CG lightning flashes. Contrary to the findings for flash rates, both peak currents and positive flash percentages were larger in Beryl's nontornadic storms than in the tornadic ones.

  12. Ages constraints in pegmatite province related to charnockitic host rocks in Minas Gerais, Brazil

    OpenAIRE

    De Mello, Fernando Machado; Bilal, Essaïd

    2012-01-01

    Cambrian-Neoproterozoic granitoids suites in southeastern Brazil are the main host rocks of largest pegmatite field of Brazil, the Eastern Pegmatite Province. The P-Li-Nb pegmatites group represent the richest in precious stones like Beryl, Aquamarine, Topaz and Tourmaline. Two types of pegmatites are characterized by their mineralogical characteristics and tectonic and magmatic relations. The first group formed during compressive event about 582 Ma and the second pegmatite group was formed b...

  13. 40 CFR 421.152 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Science.gov (United States)

    2010-07-01

    ... available. Except as provided in 40 CFR 125.30 through 125.32, any existing point source subject to this... 0.000 0.000 pH 1 1 1Within the range of 7.5 to 10.0 at all times. (k) Beryl Ore Gangue Dewatering... the range of 7.5 to 10.0 at all times. (l) Bertrandite Ore Gangue Dewatering. BPT Limitations for...

  14. Técnicas de Identificación Gemológica Técnicas de Identificación Gemológica

    OpenAIRE

    Romero-Ordoñez Fernando H.; Rubiano L. Manuel

    1997-01-01

    Due to the value and demand of the gem varieties of corundum (ruby, sapphire) as well as beryl (emerald, aquamarine), diamond and quartz (amethyst, citrine), an increasing number of synthetic stones of these gem varieties is produced. With improving techniques it is easy for synthetic gems to grow with properties similar to those of their natural counterparts or even stones without significant inclusions of diagnostic value. For this reason, the determination of physical properties of gems, u...

  15. Pressure-temperature-fluid constraints for the Emmaville-Torrington emerald deposit, New South Wales, Australia: Fluid inclusion and stable isotope studies

    Science.gov (United States)

    Loughrey, Lara; Marshall, Dan; Jones, Peter; Millsteed, Paul; Main, Arthur

    2012-06-01

    The Emmaville-Torrington emeralds were first discovered in 1890 in quartz veins hosted within a Permian metasedimentary sequence, consisting of meta-siltstones, slates and quartzites intruded by pegmatite and aplite veins from the Moule Granite. The emerald deposit genesis is consistent with a typical granite-related emerald vein system. Emeralds from these veins display colour zonation alternating between emerald and clear beryl. Two fluid inclusion types are identified: three-phase (brine+vapour+halite) and two-phase (vapour+liquid) fluid inclusions. Fluid inclusion studies indicate the emeralds were precipitated from saline fluids ranging from approximately 33 mass percent NaCl equivalent. Formational pressures and temperatures of 350 to 400 °C and approximately 150 to 250 bars were derived from fluid inclusion and petrographic studies that also indicate emerald and beryl precipitation respectively from the liquid and vapour portions of a two-phase (boiling) system. The distinct colour zonations observed in the emerald from these deposits is the first recorded emerald locality which shows evidence of colour variation as a function of boiling. The primary three-phase and primary two-phase FITs are consistent with alternating chromium-rich `striped' colour banding. Alternating emerald zones with colourless beryl are due to chromium and vanadium partitioning in the liquid portion of the boiling system. The chemical variations observed at Emmaville-Torrington are similar to other colour zoned emeralds from other localities worldwide likely precipitated from a boiling system as well.

  16. Raman microscopic study at 300 and 77 K of some pegmatite minerals from the Iveland-Evje area, Aust-Agder, Southern Norway.

    Science.gov (United States)

    Kloprogge, J T; Frost, R L

    2000-02-15

    The Raman spectra at 300 and 77 K of beryl, columbite-tantalite and topaz single crystals from pegmatites in the Iveland-Evje area are described in detail. The beryl is shown to contain mainly water type I and less of type II in its channels, while CO2 is only a very minor channel constituent. Cooling to 77 K results in minor shifts towards higher wavenumbers for most bands. The Si-O vibrations at 1009 and 1066 cm(-1) show a doubling to four bands at 1015, 1072, 1087 and 1149 cm(-1) due to structural rearrangements in the hexameric rings forming the channels in the beryl crystal structure. In addition a new band becomes visible around 1155 cm(-1). The tantalite could not be analysed in detail due to strong fluorescence. The Raman spectrum of the yellow topaz from Solås is comparable to that of the colourless topaz from Topaz Mountain, Thomas Range, Utah. Upon cooling to 77 K, two OH-stretching bands become visible around 3644 and 3655 cm(-1), which were not observed at room temperature. PMID:10794464

  17. Lithium anomaly near Pringle, southern Black Hills, South Dakota, possibly caused by unexposed rare-mineral pegmatite

    Science.gov (United States)

    Norton, James Jennings

    1984-01-01

    Six samples of biotite schist from a site near Pringle, South Dakota, contained from 140 to 750 parts per million lithium. These values are far greater than are found in mica schists in most of the rest of the southern Black Hills. The lithium may have emanated from concealed lithium pegmatite, and such pegmatite can be of interest as a possible source of rare minerals, especially tantalite and beryl. Whether making a full test of the anomaly will become economically judicious is much less clear.

  18. P-T path fluid evolution in the Gross Spitzkoppe granite stock, Namibia

    Directory of Open Access Journals (Sweden)

    Stephen Frindt

    2002-01-01

    Full Text Available The Gross Spitzkoppe granite stock (GSS is a zoned 30 km^2 epizonal intrusion that consists of three main granites: 1 medium-grained biotite granite (marginal, 2 a coarse-grained biotite granite, and 3 a central, porphyritic granite. The stock contains pegmatites as banded marginal stockscheiders and isolated pockets composed of large alkali feldspar and quartz, dark mica, interstitial fluorite, and euhedral topaz and beryl crystals. In the porphyritic granite there are local wolframite-bearing greisens and hydrothermal fluorite and topaz-rich veins.Fluid inclusion studies were conducted on: 1 topaz and quartz crystals from the marginal stockscheider; 2 quartz, topaz, fluorite and beryl crystals from isolated pegmatites; 3 topaz from a miarolitic pegmatite; 4 beryl and quartz veins from greisenized porphyritic granite; and 5 fluorite from a late fluorite vein inthe coarse-grained biotite granite. Preliminary data indicate the presence of three compositionally distinct primary and pseudosecondary inclusion types that are of late magmatic-hydrothermal origin.Type 1. Low salinity (0–10 eq. wt% NaCl H2O (± CO2 inclusions that homogenize to the liquid phase in the temperature range of 300 to 550˚C. These inclusions are from quartz, topaz and beryl. Inclusions in fluorite from the fluorite vein homogenize at ~170˚C and have a salinity of ca. 1–2 eq. wt% NaCl.Type 2. Saline (25–30 eq. wt% NaCl halite-bearing H2O (± CO2 inclusions that homogenize to the liquid phase in the temperature range of 300 to 400˚C. These inclusions are from quartz.Type 3. Low salinity (0–3 eq. wt% NaCl H2O-CO2 inclusions that homogenize to vapor phase in the temperature range of 330 to 550˚C. These inclusions are from quartz and topaz.Hydrothermal fluids from greisen minerals are represented by type 1 and type 2 H2O inclusions. They are predominantly of low salinity (~8 eq. wt% NaCl and homogenize to the liquid phase in the temperature range of 300 to 500

  19. Experimental evidence of thermal fluctuations on the X-ray absorption near-edge structure at the aluminum K-edge

    OpenAIRE

    Manuel, Damien; Cabaret, Delphine; Brouder, Christian; Sainctavit, Philippe; Bordage, Amélie; TRCERA, Nicolas

    2012-01-01

    After a review of temperature-dependent experimental x-ray absorption near-edge structure (XANES) and related theoretical developments, we present the Al K-edge XANES spectra of corundum and beryl for temperature ranging from 300K to 930K. These experimental results provide a first evidence of the role of thermal fluctuation in XANES at the Al K-edge especially in the pre-edge region. The study is carried out by polarized XANES measurements of single crystals. For any orientation of the sampl...

  20. Optical properties of natural and synthetic minerals

    International Nuclear Information System (INIS)

    The results of investigation of optical absorption and photoluminescence (PL) of topaz, beryl and yttrium aluminium garnet crystals doped with different concentrations of transition ions exposed to fast neutron irradiation and electron irradiation are presented. We suppose that irradiation leads to the formation of two types of complex centers: “Me2+- F+ (or F) centre” and complex centers, which consist of a cation vacancy and an impurity (iron, manganese and chromium) ion. Exchange interaction between radiation defects and impurity ions during neutron or electron irradiation gives rise to appearance of additional absorption and luminescence band broadening in investigated crystals. (author)

  1. Brazilian gemstones

    Science.gov (United States)

    Franco, Rui Ribeiro

    1981-04-01

    Brazil counts as a gemmological province because of the variety of gem minerals present in the country. Most Brazilian states and territories produce gemstones, the State of Minas Gerais being the most important producer both in volume and in number of species. Diamonds are chiefly derived by panning from alluvial deposits in Minas Gerais, Mato Grosso and Goiás. Among other gemstones, the most important are aquamarines, beryls, chrysoberyls, topazes, amethysts, tourmalines, emeralds and agates, and their respective varieties. The occurrences of these gemstones, as well as of a great number of others, are described for each state in which they are found.

  2. Quantum behaviour of water molecule in gemstone: terahertz fingerprints

    Science.gov (United States)

    Zhukova, Elena S.; Gorshunov, Boris P.; Torgashev, Victor I.; Lebedev, Vladimir V.; Shakurov, Gil'man S.; Kremer, Reinhard K.; Pestrjakov, Efim V.; Thomas, Victor G.; Fursenko, Dimitry A.; Dressel, Martin

    2014-03-01

    We have shown that a weak interaction of a lone H2O molecule with the ''walls'' of nano-sized crystalline cage of gemstone (beryl) results in emergence of a rich set of molecular vibrational states. By analogy with translational and librational bands in liquid water and ice corresponding absorption bands are explained as due to translational (T) and librational (L) movements of the H2O molecule which is hydrogen bonded to the cage walls. In beryl crystal lattice, however, the six-fold symmetry of the cage brings about additional effect of splitting of the T and L bands into fine structure due to tunnelling within the six-well potential relief. The presented results will be of use for analysis of more complicated systems with confined water molecules like H2O chains in carbon nano-tubes, molecular clusters in e.g. zeolites, clays, silica gels and other natural or synthetic frameworks, as well as for interfacial water in biological systems.

  3. Emerald mineralization and metasomatism of amphibolite, khaltaro granitic pegmatite - Hydrothermal vein system, Haramosh Mountains, Northern Pakistan

    Science.gov (United States)

    Laurs, B.M.; Dilles, J.H.; Snee, L.W.

    1996-01-01

    Emerald mineralization is found within 0.1- to 1-m-thick hydrothermal veins and granitic pegmatites cutting amphibolite within the Nanga Parbat - Haramosh massif, in northern Pakistan. The amphibolite forms a sill-like body within garnet-mica schist, and both are part of a regional layered gneiss unit of Proterozoic (?) age. The 40Ar/39Ar data for muscovite from a pegmatite yield a plateau age of 9.13 ?? 0.04 Ma. Muscovite from mica schist and hornblende from amphibolite yield disturbed spectra with interpreted ages of 9 to 10 Ma and more than 225 Ma, respectively, which indicate that peak Tertiary metamorphism reached 325 to 550??C prior to 10 Ma. Pegmatites were emplaced after peak metamorphism during this interval and are older than pegmatites farther south in the massif. At Khaltaro, simply zoned albite-rich miarolitic pegmatites and hydrothermal veins containing various proportions of quartz, albite, tourmaline, muscovite, and beryl are associated with a 1- to 3-m-thick heterogeneous leucogranite sill, that is locally albitized. The pegmatites likely crystallized at 650 to 600??C at pressures of less than 2 kbar. Crystals of emerald form within thin (0.20, 0.54-0.89 wt%), to pale blue beryl (emerald results from introduction of HF-rich magmatic-hydrothermal fluids into the amphibolite, which caused hydrogen ion metasomatism and released Cr and Fe into the pegmatite-vein system.

  4. Geoquímica y metalogénesis de las pegmatitas y granitos asociados del sector sur del distrito Comechingones, Córdoba

    Directory of Open Access Journals (Sweden)

    Demartis, Manuel

    2011-12-01

    Full Text Available Geochemical and metallogenetical study of the pegmatites and associated granites from southern Comechingones pegmatitic field, Córdoba. The Comechingones pegmatitic field (CPF is located in theeastern flank of the Sierra de Comechingones, Córdoba province. It is composed of granite pegmatites belonging to the Rare-Element class, beryl type, beryl-columbite-phosphate subtype; some of them are transitional into the Muscovite class. Beryllium, Nb, Ta and U deposits, as well as high-quality industrial mineral deposits, are frequently associated with these pegmatites. In the southern part of the CPF two different pegmatite types have been described.Type I pegmatites constitute large zoned bodies with up to 1000 m long and 50 m thick, and may constitute rare element deposits, whereas type II pegmatites occur as small, unzoned quartz-rich dykes, without metalliferous mineralizations, spatial and genetically associated with aplitic leucogranites. Preliminary geochemical data from bothpegmatites types and granites are presented and discussed in this contribution. Geochemical evidences, supported by field and petrographic observations, suggest that the two types of pegmatites identified in the study area represent two different, probably diachronic, magmatic stages. Type I pegmatites display a geochemical gradation in a S-N direction, from barren pegmatites in the south to fractionated pegmatites in the northern part of the study area, andare the lithological product of the first magmatic stage. The second stage lead to the crystallization of aplitic granites and barren type II pegmatites, geochemically less fractionated than type II pegmatites.

  5. Stability of some soft X-ray monochromator crystals in synchrotron radiation

    International Nuclear Information System (INIS)

    The stability in synchrotron radiation of β-alumina and beryl has been investigated by exposing the crystals in a white beam at CHESS operating at 5.2 GeV electron energy over a period of approx. equal to 100 h at an average radiant power of 28 W/cm2. Rocking curves at the CuKsub(α) energy were used to monitor the diffraction properties before and after exposure to synchrotron radiation. A Si(220) crystal was used as the first crystal. It was found that both materials exhibit no catastrophic material failure. β-alumina is clearly proven stable with no degradation of its rocking characteristics. There was in fact indication of reflectivity improvement after exposure. Results on beryl are not conclusive because the starting material (a mineral specimen) had a lot of inherent microstructural and crystallographic defects. Rocking curves in the soft X-ray region at 10.5 A were also determined using a (10anti 10) RAP crystal as first crystal. A 19-layer 50 A d-spacing Nb-C sputtered film was also characterized for comparison. (orig.)

  6. Application of X-ray diffraction technique for determining triclinicity of alkali-feldspar from the rare metal pegmatites of the Pandikimal Area, North Orissa, India

    International Nuclear Information System (INIS)

    The zoned rare metal pegmatites of Archaean age in the Jharsuguda district of north Orissa, eastern India, are well-known for their potentiality for Nb, Ta, and Be minerals. They also contain limited Li, Bi, Th, and U minerals. Because of the economic concentrations of the ore minerals of Nb-Ta and Be, they are being mined for recovering columbite-tantalite and beryl. In this paper, the values of triclinicity of alkali-feldspars, determined by X-ray diffraction, are presented and, based on the same data, the evolutionary history of the rare metal pegmatites is traced. The values of triclinicity range from 0.83 to 0.97 with an average of 0.92. The high values of triclinicity suggest that the investigated alkali-feldspars from the rare metal pegmatites of the Pandikimal area belong to the category of maximum microcline. It would, thus, mean that during the crystallisation of alkali-feldspar, and by implication their host rare metal pegmatites, not only was the rate of cooling slow, the temperature of crystallisation was also falling. Accordingly, it is interpreted that the rare metal pegmatites of the Pandikimal area crystallised slowly under a falling-temperature regime in deep-seated plutonic conditions. The presence of large beryl crystals in the rare metal pegmatites also supports this interpretation. (author)

  7. Croquet club

    CERN Multimedia

    Croquet club

    2016-01-01

    The CERN Croquet season started Saturday 7 May with the annual opening tournament. A total of 14 very happy players in the spring sunshine. It was a  lovely day in all senses - friendly competition, a lot of laughter and catching up with one another. Players are divided into PROs (low-handicap) and AMs (high-handicap), all matches are played as doubles. The pairings are changed during the day and the individual points go towards determining the winner. Congratulations to Ian Sexton for winning the Pros and Beryl Allardyce who won the Ams. Many of the games were very close and Ian seemed to have some good challenges in his block! Overall results: Pros: 1st - Ian 2nd - Brian 3rd - Angelina 4th - Jean Ams: 1st - Beryl 2nd - Frank 3rd - Peter (+Margaret) 4th - Roberta (+Jenny) Special thanks to the manager Danny Davids for making this tournament such a smooth and well run affair. CERN croquet club hold...

  8. Croquet club

    CERN Document Server

    Croquet club

    2016-01-01

    The CERN Croquet season started Saturday 7 May with the annual opening tournament. A total of 14 very happy players in the spring sunshine. It was a  lovely day in all senses - friendly competition, a lot of laughter and catching up with one another. Players are divided into PROs (low-handicap) and AMs (high-handicap), all matches are played as doubles. The pairings are changed during the day and the individual points go towards determining the winner. Congratulations to Ian Sexton for winning the Pros and Beryl Allardyce who won the Ams. Many of the games were very close and Ian seemed to have some good challenges in his block! Overall results: Pros: 1st - Ian 2nd - Brian 3rd - Angelina 4th - Jean Ams: 1st - Beryl 2nd - Frank 3rd - Peter (+Margaret) 4th - Roberta (+Jenny) Special thanks to the manager Danny Davids for making this tournament such a smooth and well run affair. CERN croquet club holds...

  9. Quantum behaviour of water molecule in gemstone: terahertz fingerprints

    International Nuclear Information System (INIS)

    We have shown that a weak interaction of a lone H2O molecule with the ''walls'' of nano-sized crystalline cage of gemstone (beryl) results in emergence of a rich set of molecular vibrational states. By analogy with translational and librational bands in liquid water and ice corresponding absorption bands are explained as due to translational (T) and librational (L) movements of the H2O molecule which is hydrogen bonded to the cage walls. In beryl crystal lattice, however, the six-fold symmetry of the cage brings about additional effect of splitting of the T and L bands into fine structure due to tunnelling within the six-well potential relief. The presented results will be of use for analysis of more complicated systems with confined water molecules like H2O chains in carbon nano-tubes, molecular clusters in e.g. zeolites, clays, silica gels and other natural or synthetic frameworks, as well as for interfacial water in biological systems

  10. Mineralogical and geochemical characteristics of the Archaean LCT pegmatite deposit Cattlin Creek, Ravensthorpe, Western Australia

    Science.gov (United States)

    Bauer, Matthias; Dittrich, Thomas; Seifert, Thomas; Schulz, Bernhard

    2014-05-01

    The LCT (lithium-cesium-tantalum) pegmatite Cattlin Creek is located about 550 km ESE of Perth, Western Australia. The complex-type, rare-element pegmatite is hosted in metamorphic rocks of the Archaean Ravensthorpe greenstone belt, which constitutes of the southern edge of the Southern Cross Terranes of the Yilgarn Craton. The deposit is currently mined for both lithium and tantalum by Galaxy Resources Limited since 2010. The pegmatitic melt intruded in a weak structural zone of crossing thrust faults and formed several pegmatite sills, of which the surface nearest mineralized pegmatite body is up to 21 m thick. The Cattlin Creek pegmatite is characterized by an extreme fractionation that resulted in the enrichment of rare elements like Li, Cs, Rb, Sn and Ta, as well as the formation of a vertical zonation expressed by distinct mineral assemblages. The border zone comprises a fine-grained mineral assemblage consisting of albite, quartz, muscovite that merges into a medium-grained wall zone and pegmatitic-textured intermediate zones. Those zones are manifested by the occurrence of megacrystic spodumene crystals with grain sizes ranging from a couple of centimeters up to several metres. The core zone represents the most fractionated part of the pegmatite and consists of lepidolite, cleavelandite, and quartz. It also exhibits the highest concentrations of Cs (0.5 wt.%), Li (0.4 wt.%), Rb (3 wt.%), Ta (0.3 wt.%) and F (4 wt.%). This zone was probably formed in the very last crystallization stage of the pegmatite and its minerals replaced earlier crystallized mineral assemblages. Moreover, the core zone hosts subordinate extremely Cs-enriched (up to 13 wt.% Cs2O) mineral species of beryl. The chemical composition of this beryl resamples that of the extreme rare beryl-variety pezzotaite. Other observed subordinate, minor and accessory minerals comprise tourmaline, garnet, cassiterite, apatite, (mangano-) columbite, tantalite, microlite (Bi-bearing), gahnite, fluorite

  11. A compact low cost “master–slave” double crystal monochromator for x-ray cameras calibration of the Laser MégaJoule Facility

    International Nuclear Information System (INIS)

    The Alternative Energies and Atomic Energy Commission (CEA-CESTA, France) built a specific double crystal monochromator (DCM) to perform calibration of x-ray cameras (CCD, streak and gated cameras) by means of a multiple anode diode type x-ray source for the MégaJoule Laser Facility. This DCM, based on pantograph geometry, was specifically modeled to respond to relevant engineering constraints and requirements. The major benefits are mechanical drive of the second crystal on the first one, through a single drive motor, as well as compactness of the entire device. Designed for flat beryl or Ge crystals, this DCM covers the 0.9–10 keV range of our High Energy X-ray Source. In this paper we present the mechanical design of the DCM, its features quantitatively measured and its calibration to finally provide monochromatized spectra displaying spectral purities better than 98%

  12. A Personal Reflection on the History of Radiation Oncology at Memorial Sloan-Kettering Cancer Center

    International Nuclear Information System (INIS)

    Purpose: To provide a historical and personal narrative of the development of radiation oncology at Memorial Sloan-Kettering Cancer Center (MSKCC), from its founding more than 100 years ago to the present day. Methods and Materials: Historical sources include the Archives of MSKCC, publications by members of MSKCC, the author's personal records and recollections, and her communications with former colleagues, particularly Dr. Basil Hilaris, Dr. Zvi Fuks, and Dr. Beryl McCormick. Conclusions: The author, who spent 38 years at MSKCC, presents the challenges and triumphs of MSKCC's Radiation Oncology Department and details MSKCC's breakthroughs in radiation oncology. She also describes MSKCC's involvement in the founding of the American Society for Therapeutic Radiology and Oncology.

  13. Geologic and radiometric prospect of the mine ''El Muerto'' Oaxaca, Mex

    International Nuclear Information System (INIS)

    The studies realized in the mine demonstrated that the uranium mineral inclosure obtained in the pegmatites exists in very little concentrations and does not constitute useful deposits. Therefore, there are found rare earths minerals like monazite and euxenite so the mine may be proficient in the extraction of other type of minerals like spodumene, beryl, etc. Because of the scarce knowledges that we have about the pegmatites referring to the radiactive minerals study, it is stated the necessity of making programs perfectly coordinated and projected in the application of the metallurgic investigation that permits the increase in results of useful value, without to lose sight that the principal objective is to have a real economic, industrial and scientific view of the radiactive minerals localized in the pegmatites, considering the refractory character of the same, and the mineral little volume that in general they contain. (author)

  14. Vibrating Wire for Beam Profile Scanning

    CERN Document Server

    Arutunian, S G; Mailian, M R; Sinenko, I G; Vasiniuk, I E

    1999-01-01

    The method for measurement of transverse profile (emittance) of the bunch by detecting of radiation arising scattering at of the bunch on the scanning wire is wide-spread. In this work the information about scattering bunch is proposed to measure using the oscillation frequency of the tightened scanning wire. In such way the system of radiation (or secondary particles) extraction and measurement can be removed. Dependence of oscillations frequency on beam scattering is determined by several factors, including changes of wire tension caused by transverse force of the beam, influence of beam self field. Preliminary calculations show that influence caused by wire heating will dominate. We have studied strain gauges on the basis of vibrating wire from various materials (tungsten, beryl bronze, niobium zirconium alloys). A scheme of self oscillations generation by alternating current in autogeneration circuit with automatic frequency adjustment was selected. Special method of wire fixation and elimination of trans...

  15. Radiation dosimetry using decreasing TL intensity in a few variety of silicate minerals

    International Nuclear Information System (INIS)

    When the TLD is used for Radiation Dosimetry, the calibration curve is produced by plotting increasing TL intensity as function of dose. There are cases where the TL intensity decreases as dose increases and can be used in radiation dosimetry. Such behavior can be found in green quartz, three varieties of beryl and pink tourmaline. In all these silicate crystals we can show that if we irradiate with increasing γ-dose there is a dose Dm for which the TL intensity is maximum. Of course, Dm varies depending on the crystal and irradiated crystal with the dose Dm is stable. If we take one of these crystals and irradiate with dose Dm and we irradiate with doses from low values up to 400-500 Gy we obtain a curve of decreasing TL intensity, such curve can be used as calibration curve. (authors)

  16. Reported industrial minerals occurrences and permissive areas for other occurrences in the Islamic Republic of Mauritania, (phase V, deliverable 89): Chapter R in Second projet de renforcement institutionnel du secteur minier de la République Islamique de Mauritanie (PRISM-II)

    Science.gov (United States)

    Langer, William H.

    2015-01-01

    Previous PRISM reports discuss a variety of industrial minerals. Gypsum, phosphate, salt, stone, sulfur, and ilmenite command the majority of the attention in the earlier geologic reports. (Ilmenite is evaluated in a separate U.S. Geological Survey report in the current study). Asbestos, arsenic, barite, fluorite, and kaolin are listed in indices (occurrence datasets) as potential mineral resources (Marsh and Anderson, 2015), but previous reports do not elaborate on their development potential. Beryl, described herein with the discussions of pegmatites, is also listed in indices of potential mineral resources, but has not been described in terms of its industrial mineral potential. Short discussions on the potential for cement (carbonate rocks), glass sand, peat, and sillimanite resources are included in this report.

  17. Effects of Cr 3+ impurity concentration on the crystallography of synthetic emerald crystals

    Science.gov (United States)

    Lee, Pei-Lun; Huang, Eugene; Lee, Jan-Shing; Yu, Shu-Cheng

    2011-06-01

    Flux method has been adopted for the synthesis of emerald crystals using PbO-V 2O 5 as a flux in order to study the crystallography of the synthetic crystals. In general, the hue of green color of emerald deepens with the addition of Cr 3+. The molar volume of the synthesized crystals was found to increase with the incorporation of Cr 2O 3 dopant. The substitution of Cr 3+ for Al 3+ in the octahedral sites of beryl results in the expansion of a-axis, while c-axis remains nearly unchanged. The maximum Cr 2O 3-content allowed in the crystal lattice of emerald has been found to be about 3.5 wt%. When the doping Cr 2O 3-content exceeds 3.5 wt%, a significant anomaly in lattice parameters starts to take place, accompanying the precipitation of an unknown phase in the emerald matrix.

  18. The first occurrence of elbaite in Poland

    Directory of Open Access Journals (Sweden)

    Michał Sachanbiński

    2004-01-01

    Full Text Available An amphibolite-hosted quartzo-feldspar-mica pegmatite with schorl, green elbaite, spessartine,andalusite, spinel, hyalophane, zircon, columbite and beryl was found near Gilów in the E part of theGóry Sowie gneissic block (Lower Silesia, Poland. The black tourmaline crystals are chracterized by thechange of their composition from Mg- and Al-enriched schorl, typical of the Góry Sowie block, to Al- and,Al- and Li-enriched schorl, and to Fe-bearing elbaite. Light green tourmaline corresponds to (Fe,Mn--bearing elbaite. The crystallization sequence of the tourmaline varieties results from progressive change ofcomposition of pegmatite melts in the last metamorphic stage of a parent sedimentary protolith around370–380 Ma ago. The stage of Li-bearing tourmaline formation corresponds to crystallization of a phosphateassemblage with ferrisicklerite-sarcopside-graftonite lamellar intergrowths known from other pegmatites ofthe Góry Sowie block.

  19. Mineralogy and geochemistry of rare metal pegmatite, Metapal, Bastar district, Madhya Pradesh, India

    International Nuclear Information System (INIS)

    The Metapal pegmatite emplaced in granite, is an isolated, fully differentiated and complex type of granite pegmatite with well developed zoning and distinct albitised and greisenised replacement units rich in ixiolite and beryl. Other rare element minerals that are present include, euxenite, aeschynite, microlite, monazite, and cassiterite. Ixiolite mineral is being reported and characterized for the first time from this pegmatite of India. Enrichment of Rb, low Sr, K/Rb and Sr/Rb in perthitic feldspar and high Nb, Sn, and Ga in muscovite also signify the highly differentiated and mineralised nature of Metapal pegmatite. The pegmatite has undergone shallow weathering resulting in limited colluvial placers rich in Nb-Ta minerals. (author)

  20. Mineral potential for incompatible element deposits hosted in pegmatites, alkaline rocks, and carbonatites in the Islamic Republic of Mauritania (phase V, deliverable 87): Chapter Q in Second projet de renforcement institutionnel du secteur minier de la République Islamique de Mauritanie (PRISM-II)

    Science.gov (United States)

    Taylor, Cliff D.; Giles, Stuart A.

    2015-01-01

    Review of PRISM-I documents and the National inventory of mineral occurrences suggests that resources of U, Th, Nb, Ta, Be, rare earth elements (REEs) and fluorite are known in Mauritania and have been exploited in the past at the Bou Naga alkaline complex. Several different deposit types are indicated by the available data. Pegmatitic veins are recorded in several areas of the Archean and Paleoproterozoic portions of the Rgueïbat Shield and are prospective for resources of Li, Be, Nb, Ta, U, Th, and REEs. Over 150 beryl pegmatites are known in the Khnefissat and Inkebden areas of the Chami greenstone belt, and additional concentrations of pegmatites are known in the Guelb Nich Sud area of the Sebkhet Nich greenstone belt and in the northeastern part of the Amsaga Complex. Due to the small size of these deposits, they are unlikely to be economic unless additional value can be gained by processing contained minerals for their industrial uses.

  1. Quantum Behavior of Water Molecules Confined to Nanocavities in Gemstones.

    Science.gov (United States)

    Gorshunov, Boris P; Zhukova, Elena S; Torgashev, Victor I; Lebedev, Vladimir V; Shakurov, Gil'man S; Kremer, Reinhard K; Pestrjakov, Efim V; Thomas, Victor G; Fursenko, Dimitry A; Dressel, Martin

    2013-06-20

    When water is confined to nanocavities, its quantum mechanical behavior can be revealed by terahertz spectroscopy. We place H2O molecules in the nanopores of a beryl crystal lattice and observe a rich and highly anisotropic set of absorption lines in the terahertz spectral range. Two bands can be identified, which originate from translational and librational motions of the water molecule isolated within the cage; they correspond to the analogous broad bands in liquid water and ice. In the present case of well-defined and highly symmetric nanocavities, the observed fine structure can be explained by macroscopic tunneling of the H2O molecules within a six-fold potential caused by the interaction of the molecule with the cavity walls. PMID:26283245

  2. Study of the mass attenuation coefficients and effective atomic numbers in some gemstones

    International Nuclear Information System (INIS)

    The total mass attenuation coefficients for natural beryl, corundum, garnet, pearl, and tourmaline gemstones were measured at 81, 356.5, 661.6, 1173.2, and 1332.5 keV photon energies. The samples were irradiated with 133Ba, 137Cs and 60Co radioactive point sources using gamma ray transmission method. Total atomic and electronic cross-sections, effective atomic numbers and electron densities were determined experimentally and theoretically. The experimental values were compared with the calculated values for all samples. The calculations were extended for total photon interactions in a wide energy range (1 keV-100 GeV) using WinXCom program of the most commonly irradiated gemstones with different sources of ionized radiation. The values of these parameters have been found to vary with photon energy and chemical composition of the gemstones. All variations of these parameters against energy are shown graphically for total photon interactions. (author)

  3. Geología y mineralogía de algunas pegmatitas del borde oriental del distrito Punilla, Córdoba Geology and mineralogy of some pegmatites in the eastern border of the Punilla District, Córdoba province

    Directory of Open Access Journals (Sweden)

    F. Colombo

    2006-09-01

    -zoned and are of rare-element class, complex type, beryl-columbite subtype. They probably belong to the hybrid family. Minerals found in all pegmatites include quartz, ordered microcline, plagioclase and muscovite (occasionally pink due to Mn>Fe. Biotite is a very frequent accessory. Beryl can be classified as alkali-poor sodicpotassic beryl and has Fe replacing Al in its structure. Fluorapatite, displaying a marked negative Eu anomaly, may contain up to 2.95% Mn and 0.77% Fe. Xenotime-(Y occurs as inclusions within apatite. Garnet (spessartine-almandine is compositionally unzoned. Other minerals found in small quantities are fluorite, rutile, hematite, columbite-group minerals (generally Nb>Ta and Fe>Mn with disordered structure, members of the pyrochlore group (mainly Nb-, Pb- and U-rich, malachite, mottramite, zircon (with low to null Hf, chrysocolla, kaolinite, interstratified illite/smectite, illite, bertrandite, kettnerite, bismutite, clinobisvanite and probably gahnite. Fluid inclusions in beryl and miarolitic quartz from SD-2 show that supercritical CO2 was present in a stage of the pegmatite evolution. Late solutions have no detectable CO2 and record a cooling history. These pegmatites crystallized from a Be-rich peraluminous melt, with Nb>>Ta, between 0.4 and 0.8% P2O5 and almost no S. Fractionation of Mn from Fe was moderate.

  4. Progress in the Synthesis of 4 -Trifluoromethylphenyl Acetic Acid%对三氟甲基苯乙酸的合成研究进展

    Institute of Scientific and Technical Information of China (English)

    邓绍平; 陈洁

    2012-01-01

    Research progress on the synthesis method of 4 -trifluoromethylphenyl acetic acid and its application as pharmaceutical intermediate in the synthesis of pharmaceuticals were described. The methods including 4 -trifluoromethyl beryl chloride, 4 -trifluoromethyl acetophenone, diethyl malonate and 4 - trifluoromethyl aniline were reviewed and summarized.%叙述了对三氟甲基苯乙酸合成方法的研究进展,及其作为医药中间体在药物合成中的应用。将对三氟甲基氯苄法、对三氟甲基苯乙酮法、丙二酸二乙酯法、对三氟甲基苯胺法合成对三氟甲基苯乙酸进行了概括总结。

  5. Doppler Radar and Cloud-to-Ground Lightning Observations of a Severe Outbreak of Tropical Cyclone Tornadoes

    Science.gov (United States)

    McCaul, Eugene W., Jr.; Buechler, Dennis; Cammarata, Michael; Arnold, James E. (Technical Monitor)

    2002-01-01

    Data from a single WSR-88D Doppler radar and the National Lightning Detection Network are used to examine the characteristics of the convective storms that produced a severe tornado outbreak within Tropical Storm Beryl's remnants on 16 August 1994. Comparison of the radar data with reports of tornadoes suggests that only 12 cells produced the 29 tornadoes that were documented in Georgia and the Carolinas on that date. Six of these cells spawned multiple tornadoes, and the radar data confirm the presence of miniature supercells. One of the cells was identifiable on radar for 11 hours, spawning tornadoes over a time period spanning approximately 6.5 hours. Time-height analyses of the three strongest supercells are presented in order to document storm kinematic structure and evolution. These Beryl mini-supercells were comparable in radar-observed intensity but much more persistent than other tropical cyclone-spawned tornadic cells documented thus far with Doppler radars. Cloud-to-ground lightning data are also examined for all the tornadic cells in this severe swarm-type tornado outbreak. These data show many of the characteristics of previously reported heavy-precipitation supercells. Lightning rates were weak to moderate, even in the more intense supercells, and in all the storms the lightning flashes were almost entirely negative in polarity. No lightning at all was detected in some of the single-tornado storms. In the stronger cells, there is some evidence that lightning rates can decrease during tornadogenesis, as has been documented before in some midlatitude tornadic storms. A number of the storms spawned tornadoes just after producing their final cloud-to-ground lightning flashes. These findings suggest possible benefits from implementation of observing systems capable of monitoring intracloud as well as cloud-to-ground lightning activity.

  6. Geology and pegmatites of part of the Fourmile area, Custer County, South Dakota

    Science.gov (United States)

    Lang, Andrew J.; Redden, Jack Allison

    1953-01-01

    The Fourmile area, Custer County, S. Dak., is underlain by pre-Cambrian metamorphic rocks that surround the granitic core of the Black Hills. The main structure in the area is the upright limb of an overturned anticline that plunges about 30 ? S. 10 ? E. Three units of metamorphic rocks are described that have a total thickness of at least 7, 700 feet. The oldest of these units, a quartz-mica schist, is more than 6, 500 feet thick. The overlying unit, about 200 feet thick, is composed of thin beds of amphibolite and hornblende schist, lime-silicate rock, cordierite-biotite schist, microcline-biotite schist, and other types of rocks. The youngest unit, a quartz-mica-feldspar schist, is more than 1,000 feet thick. The presence of kyanite, staurolite, cordierite, and sillimanite in the rocks indicates that they have been subjected to high-grade metamorphism. About 420 pegmatites were mapped in the quartzmica-schist and the quartz-mica-feldspar schist. A few thin pegmatites in the third unit were not mapped. Most of these are concordant with the schistosity and relict (?) bedding of the enclosing metamorphic rocks. They are as much as 250 feet thick and range from 10 to 2, 600 feet in length. Nine peqmatites are zoned and classified as heterogeneous. The remainder are homogeneous and are poorly zoned. The major constituents are plaqioclase, quartz, perthite, and muscovite. The accessory minerals are tourmaline, apatite, garnet, and biotite. Beryl was observed in 15 peqmatites. The heterogeneous pegmatites contain commercial deposits of potash feldspar, mica (sheet and scrap), and beryl.

  7. Reaction of sources of resistance to white mold to microsatellite haplotypes of Sclerotinia sclerotiorum

    Directory of Open Access Journals (Sweden)

    Miller da Silva Lehner

    2016-04-01

    Full Text Available ABSTRACT White mold caused by the fungus Sclerotinia sclerotiorum is the most yield-limiting disease of common bean in Brazil. To date, there has been no commercial cultivar resistant to this disease. In a greenhouse we evaluated white mold resistance sources (Cornell 605, A195 and G122 against eight isolates of S. sclerotiorum from five Brazilian states. A Brazilian cultivar (BRSMG Madrepérola and a susceptible check (Beryl were used as control. Treatments were arranged in factorial combinations (5 × 8 in a completely random design with four replicates. Disease severity was assessed on a rating scale of 1-to-9 together with lesion length, which was used to determine an area under the disease progress curve (AUDPC. Polymorphisms detected in ten microsatellite loci were used to assess variability between the isolates. Each isolate was a distinct haplotype; they formed a genetic tree with two clusters. One cluster was formed by three isolates collected from the states of Minas Gerais and São Paulo (southeastern; the others, by isolates from Paraná, Santa Catarina (southern, Goiás (Mid-western, and again, Minas Gerais. Genotype × isolate interaction was significant. In general, Beryl was more susceptible than BRSMG Madrepérola. Considering the AUDPC and/or the white mold reaction score, Cornell 605 exhibited more physiological resistance than BRSMG Madrepérola to seven isolates, A195 to five isolates, and G122 to two isolates. Our results suggest that Cornell 605 is the best source of resistance to white mold for the southern region, whereas Cornell 605 and A195 are somewhat superior to G122 for the southeastern and mid-western regions.

  8. 新疆南部祖母绿(绿柱石)成矿地质条件初探%Preliminary discussion of the the metailogenic conditions of emerald deposit, Southern Xinjiang, China

    Institute of Scientific and Technical Information of China (English)

    禹秀艳; 李甲平; 汪立今; 罗卫东; 石玉君; 陈勇; 陈俊华

    2011-01-01

    The emeralds of Xinjiang are good in quality, and the deposit has enormous potential yields of excellent quality emerald. This paper is mainly to analyze the geological characteristics of this deposit, including the regional geological features; mining and geological characteristics of ore body; ore mineralogi-cal characteristics of micro. The formation and distribution of emerald ore bodies found in Xinjiang are controlled by regional stratigraphy, magmatic, tectonic and other factors. Emerald (Beryl) Produced in the carbonaceous limestone, shale, calcite, calcite-quartz veinlets. Veins mostly were shaped by oblique veins, bedding pulse. Based on this study, according to samples collected, carrying on microscopic order of mineral assemblages and the formation of micro-mineralogy, mineralization process will be divided into three periods, namely before mineralization, mineralization period, after forming, obtained in the main ore minerals of the formation of calcite, quartz, albite, beryl, etc.. Through this research, the area emerald (beryl) exploration of important guiding significance.%新疆南部首次发现质量好的祖母绿(绿柱石),其成矿地质条件研究意义重大.本文主要对新疆南部祖母绿(绿柱石)矿的成矿地质条件进行初步探讨,包括区域地质特征、矿区及矿体地质特征、矿石显微矿物学特征等.发现新疆祖母绿矿体的形成和分布,受区内地层、岩浆、构造等多种因素和条件限制.祖母绿(绿柱石)多产于含碳质灰岩、页岩的方解石、方解石-石英细脉中,含祖母绿(绿柱石)矿脉多以斜交脉、顺层脉产出.在此研究基础上,根据所采集的样品,进行了显微矿物组合特征和生成顺序的微观矿物学研究,将成矿作用过程划分为三个期次,即成矿前、成矿期、成矿后.得出在成矿期形成的主要矿物为方解石、石英、钠长石、绿柱石等.通过上述研究,对该区祖母绿(绿柱石)找矿具有重要的指导意义.

  9. Different periods of uranium and thorium occurrence in Madagascar (1960); Cycles uraniferes et thoriferes a Madagascar (1960)

    Energy Technology Data Exchange (ETDEWEB)

    Moreau, M. [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    In Madagascar, the first typical occurrences of thorium and uranium are about 500 million years old. Previously thorium and uranium were rather concentrated in the granitic and charnockitic zones, chiefly in minerals such as monazite, apatite and zircon. At the end of the Precambrian period, metasomatic granites occur especially in the anticlinal series (Andriba orthite granite). The granitization is followed by the formation of the main pegmatitic areas in the Island with Th-U niobotantalates, uraninite and beryl. The pegmatites are well developed in the synclinal series with a poor migmatization or no migmatization at all. In the same time a large uranium and thorium province with uranothorianite deposits appears within the calcomagnesian series of the Southern part of Madagascar. Later, large amounts of monazite were carried down to the detritic Karroo sediments during tile erosion of the metamorphic precambrian rocks. Monazite has been concentrated again by frequent marine incursions, till the present time. In the medium Karroo, near Folakara, uranium minerals occur in direct relation with carbonaceous material. Finally we must note the uranium occurrence in the pleistocene carbonaceous shales of Antsirabe basin, in contact with crystalline rocks. (author) [French] A Madagascar, le premier cycle uranifere et thorifere bien caracterise se situe aux alentours de 500 millions d'annees. Auparavant, le thorium et l'uranium sont concentres de preference dans les zones granitiques et charnockites sous forme de monazite, apatite ou zircon. Vers la fin du Precambrien, se produisent des granitisations metasomatiques, surtout dans les zones anticlinales (type Andriba a orthite). La fin de cette granitisation s'accompagne de la formation des principaux champs pegmatitiques de l'Ile a niobotantalates uraniferes, uraninite et beryl, qui se developpent de preference dans les series synclinales peu ou pas migmatisees. A cette meme epoque s

  10. Analysis of archaeological precious stones from Slovenia

    Energy Technology Data Exchange (ETDEWEB)

    Šmit, Ž. [Facully of Mathematics and Physics, University of Ljubljana (Slovenia); Fajfar, H. [Jožef Stefan Institute, Ljubljana (Slovenia); Jeršsek, M. [Slovenian Museum of Natural History, Ljubljana (Slovenia); Knific, T. [National Museum of Slovenia, Ljubljana (Slovenia); Kržic, A. [Higher Vocational Centre, Sezana (Slovenia); Lux, J. [Institute for the Protection of Cultural Heritage of Slovenia, Ljubljana (Slovenia)

    2013-07-01

    Full text: Precious stones have been attractive pieces of jewelry since ancient times. However, due to the limited sources of origin, the quality of applied items mainly depended on long-range commercial relations, but also on fashion. In Antiquity and Late Antiquity, stones much used and sought for were emeralds and garnets. In Slovenia, emeralds are typically related to the early Roman period and are incorporated in the finds of gold jewelry from the graves. Emerald is generally beryl colored by admixture of chromium, though green colors can also be due to admixtures of iron or vanadium. Garnets were increasingly used by various nations of the People Migration period, and mounted in gilded silver or gold objects by 'cloisonne' or 'en cabochon' techniques. In Slovenia, numerous jewelry items containing garnets were found in the graves and in post-Roman fortified settlements. Geologically, according to the admixtures of metal ions, the garnets are divided into several species, while the most common among archaeological finds are almandines and pyropes and their intermediate types. It is also common to divide garnets into five groups, the first two originating from India, the third from Ceylon and the fifth from Czech Republic. The measurements involved presumed emeralds from Roman jewelry finds in Slovenia and comparative samples of beryl from Siberia and Habachtal in Austria. The analysis determined the coloring ions and showed relations between particular stones. For garnets, ten samples from brooches, earrings and rings were selected for the analysis on the basis of previous micro Raman examination. The analysis was performed by a combined PIXE-PIGE technique using proton beam in air. The light elements of Na, Mg, AI were determined according to the emitted gamma rays, while X-rays were used for the elements heavier than silicon. Two X-ray spectra were measured in each measuring point, soft and hard X-ray; the latter was obtained using an

  11. Chemical-mineralogical characterization and Moessbauer spectroscopy of aquamarine from Pedra Azul, Northeast of Minas Gerais

    International Nuclear Information System (INIS)

    Aquamarines from three pegmatites located the vicinities of the Pedra Azul city, Minas Gerais state, were investigated in terms of chemical composition, physical properties and Moessbauer spectroscopy. The small lenticular pegmatite bodies are usually less than 5 m wide and exhibit a conspicuous mineralogical and textural zoning. The last thermal event in these pegmatites, determined by K-Ar method in muscovite, is of Neo proterozoic age, coincident with the late stages of the Brasiliano tectono- metamorphic cycle. Chemical analyses showed that sodium is the alkali with higher contents in the aquamarines, thus enabling their classification as sodic beryls. In zoned samples there is an increase of Fe as well as Mn from center to border, while no systematic variation could be detected for other elements. The specific gravity of 2.72 to 2.80 g/cm3 is higher than the values determined for samples from other pegmatites of Minas Gerais. The refraction indices are ne=1.569 - 1.579 and NW= 1.573 - 1.581 and the birefringence varies from 0.002 to 0.008. The refraction indices increase with the Be O content. The color of aquamarines varies from medium to light blue, sometimes greenish blue. Moessbauer spectra obtained at room temperature and at 80 K show that Fe2+ is the main chromophore-ion and suggest that the iron is present in octahedral sites as well as in the structural channels. Moessbauer spectra also indicate that the incorporation of Fe3+ may cause a shift from deep blue to light blue colors. Based on their aquamarine composition the pegmatites were classified as barren, poor in rare alkalis (Li, Rb, Cs) and therefore little differentiated. The relatively simple mineralogy and the lack of lithium minerals such as lepidolite and spodumene confirm this classification. Thus, the composition of beryl can be used as a tracer for the prospection of pegmatites with different degrees of differentiation and consequently with different types of mineralization. (author)

  12. Chemical-mineralogical characterization and Moessbauer spectroscopy of aquamarine from Pedra Azul, Northeast of Minas Gerais; Caracterizacao quimico-mineralogica e espectroscopia Moessbauer de agua-marinha da regiao de Pedra Azul, nordeste de Minas Gerais

    Energy Technology Data Exchange (ETDEWEB)

    Viana, Rubia Ribeiro; Jordt-Evangelista, Hanna [Ouro Preto Univ., MG (Brazil). Escola de Minas. Dept. de Geologia]. E-mail: rubia@degeo.ufop.br; hanna@degeo.ufop.br; Costa, Geraldo Magela da [Ouro Preto Univ., MG (Brazil). Dept. de Quimica]. E-mail: magela@iceb.ufop.br

    2001-03-01

    Aquamarines from three pegmatites located the vicinities of the Pedra Azul city, Minas Gerais state, were investigated in terms of chemical composition, physical properties and Moessbauer spectroscopy. The small lenticular pegmatite bodies are usually less than 5 m wide and exhibit a conspicuous mineralogical and textural zoning. The last thermal event in these pegmatites, determined by K-Ar method in muscovite, is of Neo proterozoic age, coincident with the late stages of the Brasiliano tectono- metamorphic cycle. Chemical analyses showed that sodium is the alkali with higher contents in the aquamarines, thus enabling their classification as sodic beryls. In zoned samples there is an increase of Fe as well as Mn from center to border, while no systematic variation could be detected for other elements. The specific gravity of 2.72 to 2.80 g/cm{sup 3} is higher than the values determined for samples from other pegmatites of Minas Gerais. The refraction indices are ne=1.569 - 1.579 and NW= 1.573 - 1.581 and the birefringence varies from 0.002 to 0.008. The refraction indices increase with the Be O content. The color of aquamarines varies from medium to light blue, sometimes greenish blue. Moessbauer spectra obtained at room temperature and at 80 K show that Fe{sup 2+} is the main chromophore-ion and suggest that the iron is present in octahedral sites as well as in the structural channels. Moessbauer spectra also indicate that the incorporation of Fe{sup 3+} may cause a shift from deep blue to light blue colors. Based on their aquamarine composition the pegmatites were classified as barren, poor in rare alkalis (Li, Rb, Cs) and therefore little differentiated. The relatively simple mineralogy and the lack of lithium minerals such as lepidolite and spodumene confirm this classification. Thus, the composition of beryl can be used as a tracer for the prospection of pegmatites with different degrees of differentiation and consequently with different types of

  13. Immobilisation of beryllium in solid waste (red-mud) by fixation and vitrification.

    Science.gov (United States)

    Bhat, P N; Ghosh, D K; Desai, M V M

    2002-01-01

    The objective of this study was to obtain information on the immobilization of beryllium (Be) in solid waste generated in the extraction process of beryllium from its ore, Beryl. This solid waste, termed red-mud, contains oxides of iron, aluminium, calcium, magnesium and beryllium. The red-mud waste contains beryllium at levels above the permissible limit, which prevents its disposal as solid waste. The total beryllium content in the red-mud analysed showed value ranging from 0.39 to 0.59% Be The studies showed that 50% of the total beryllium in red-mud can be extracted by water by repeated leaching over a period of 45 days. The cement mix, casting into cement blocks, was subjected to leachability studies over a period of 105 days and immobilization factor (IF factor) was determined. These IF values, of the order of 102, were compared with those obtained by performing leachability study on vitrified red-mud masses produced at different temperature conditions. Direct heating of the red-mud gave the gray coloured, non-transparent vitreous mass (as 'bad glass') showed effective immobilisation factor for beryllium in red-mud of the order of 10(4). PMID:12092765

  14. Annual report of the Metallurgy Division [for the] period ending December 1977

    International Nuclear Information System (INIS)

    The research and development work carried out and the various programmes underway in the Metallurgy Division of the Bhabha Atomic Research Centre, Bombay, during the calendar year 1977 have been reported. The R and D work and programmes cover extraction metallurgy, physical metallurgy, alloy development, corrosion metallurgy and ceramics. Some of the major studies and programmes are: (1) development of processes for extraction of niobium, vanadium, hafnium and nickel, (2) preparation of niobium alloys, ferro-zirconium, ceramic grade zirconia, (3) electro-refining of zircaloy scrap, (4) preparation of anhydrous beryllium fluoride from Indian beryl, (5) preparation of beryllium alloys, (6) studies on phase transformation and deformation behaviour of zirconium and zirconium-oxygen alloys, (7) self-diffusion studies in dilute Zr-Fe and Zr-Cr alloys, (8) studies on corrosion and stress corrosion cracking of zirconium base alloys and (9) sintering studies on ZrO2-PuO2 and BeO. (M.G.B.)

  15. Book Reviews

    Directory of Open Access Journals (Sweden)

    A. Teeuw

    1977-10-01

    Full Text Available - P.E. de Josselin de Jong, J.H. Beaglehole, The district: A study in decentralization in West Malaysia. Hull Monographs on South-East Asia no. 6. Published for the University of Hull by Oxford University Press, 1976. 122 pages. - C.D. Grijns, Sri Soekesi Adiwimarta, Omong Djakarta-Texte (bearbeitet und übersetzt von -. Veröffentlichung des Seminars für Indonesische und Südsesprachen der Universität Hamburg Band 8. Verlag von Dietrich Reimer, Berlin, 1973. - H.K.J. Cowan, V.I. Braginskij, Evoljutsija Malajskogo klassitsjeskogo sticha. Uitg. “Nauka”, glavnaja redaktsija vostotsjnoj literatury, Moskou 1975. 206 blzn. - J.J. Ras, Wolfgang Marschall, Der Berg des Herrn der Erde, Alte Ordnung und Kulturkonflikt in einem indonesischen Dorf. Deutscher Taschenbuch Verlag, München 1976. 204 pp., 30 illustrations. - A. Teeuw, Muhammad Haji Salleh, Tradition and change in contemporary Malay-Indonesian poetry. Penerbit Universiti Kebangsaan Malaysia, Kuala Lumpur 1977. IX, 190 pp. - J.J. Ras, Beryl de Zoete, Dance and drama in Bali. Oxford University Press, Kuala Lumpur 1973. XX 343 pp., 112 illustrations., Walter Spies (eds.

  16. POLARISATION OF THE S - PHASE OF SEISMOGRAMS

    Directory of Open Access Journals (Sweden)

    R. STONELEY

    1951-06-01

    Full Text Available In earthquakes recorded at moderate distances it lias been ohservedthat S phase appears first as SII, folloived some 10 to 14 seconds laterby SV. The object of tliis paper is to try to decide ichether doublérefraction is likely to be the explanation of tliis jìlwnomenon.A simpie model to consider ivould be a « transversely isotropie »material, symmetrical about the radiai direction. Formulae for thevelocities of SII and SV waves are available; tliese velocities dependon the angle that the ray makes ivi t li the norma!. It is unlikely thatthe Eartli could be as markedly anisotropie as the minerai beryl, whichis transversely isotropie; aceordingly, this material, of ivhich the fi veclastic constants are knoivn is taken as an extreme example, andthe velocities of SH and SV for different angles of incidence are« scaled down » so as to match the velocity of distortional ivaves ingranite. It is then possible to calcitiate the difference in the timo takenby ivaves from one point of the surface of the Earth to anotlier pointon the surface according as the S wave in the surface layer is of SHor SV type.

  17. Investigating Subsidence Resulting from Ground Water Withdrawal in the Cedar Valley, Utah Region Using InSAR

    Science.gov (United States)

    Katzenstein, K.

    2012-12-01

    Ground water withdrawal has long been known as a potential source of land subsidence, particularly in arid regions where natural ground water recharge is low relative to the volumes of water produced. Throughout the last decade, Interferometric Synthetic Aperture Radar (InSAR) has proved to be a valuable tool to quantify aquifer system response to ground water withdrawal in arid portions of the western United States. The vast spatial coverage (~10,000 square miles minimum) and precise vertical resolution (subsidence features in the vicinity of the observed ground fissuring with cumulative magnitudes as high as 11 cm and 17 cm for the Enoch graben and Quichapa Lake areas respectively. Additional subsidence was detected in other areas within Cedar Valley that correspond well with the locations of active municipal ground water wells. Additionally, several subsidence features not associated with the fissures of interest were observed. One in particular located between the small communities of Enterprise and Beryl, Utah exhibits over 50 cm of subsidence during the period of this study. This agricultural area is typified by pivot irrigation with ground water produced from the local alluvial aquifer. True subsidence magnitudes may be much higher as a large portion of the area in the vicinity of the pivot irrigation is decorrelated in the InSAR result. The magnitudes and locations of all subsidence features observed are presented and discussed.

  18. The first X-ray diffraction measurements on Mars

    Science.gov (United States)

    Bish, David; Blake, David; Vaniman, David; Sarrazin, Philippe; Bristow, Thomas; Achilles, Cherie; Dera, Przemyslaw; Chipera, Steve; Crisp, Joy; Downs, R. T.; Farmer, Jack; Gailhanou, Marc; Ming, Doug; Morookian, John Michael; Morris, Richard; Morrison, Shaunna; Rampe, Elizabeth; Treiman, Allan; Yen, Albert

    2014-01-01

    The Mars Science Laboratory landed in Gale crater on Mars in August 2012, and the Curiosity rover then began field studies on its drive toward Mount Sharp, a central peak made of ancient sediments. CheMin is one of ten instruments on or inside the rover, all designed to provide detailed information on the rocks, soils and atmosphere in this region. CheMin is a miniaturized X-ray diffraction/X-ray fluorescence (XRD/XRF) instrument that uses transmission geometry with an energy-discriminating CCD detector. CheMin uses onboard standards for XRD and XRF calibration, and beryl:quartz mixtures constitute the primary XRD standards. Four samples have been analysed by CheMin, namely a soil sample, two samples drilled from mudstones and a sample drilled from a sandstone. Rietveld and full-pattern analysis of the XRD data reveal a complex mineralogy, with contributions from parent igneous rocks, amorphous components and several minerals relating to aqueous alteration. In particular, the mudstone samples all contain one or more phyllosilicates consistent with alteration in liquid water. In addition to quantitative mineralogy, Rietveld refinements also provide unit-cell parameters for the major phases, which can be used to infer the chemical compositions of individual minerals and, by difference, the composition of the amorphous component. PMID:25485131

  19. Satellite Data Assimilation of Upper-Level Sounding Channels in HWRF with Two Diff erent Model Tops

    Institute of Scientific and Technical Information of China (English)

    邹晓蕾; 翁富忠; 林琳; 张邦林; 吴陈锋; 秦正坤

    2015-01-01

    The Advanced Microwave Sounding Unit-A (AMSU-A) onboard the NOAA satellites NOAA-18 and NOAA-19 and the European Organization for the Exploitation of Meteorological Satellites (EUMETSAT) MetOp-A, the hyperspectral Atmospheric Infrared Sounder (AIRS) onboard Aqua, the High resolution In-fraRed Sounder (HIRS) onboard NOAA-19 and MetOp-A, and the Advanced Technology Microwave Sounder (ATMS) onboard Suomi National Polar-orbiting Partnership (NPP) satellite provide upper-level sounding channels in tropical cyclone environments. Assimilation of these upper-level sounding channels data in the Hurricane Weather Research and Forecasting (HWRF) system with two diff erent model tops is investigated for the tropical storms Debby and Beryl and hurricanes Sandy and Isaac that occurred in 2012. It is shown that the HWRF system with a higher model top allows more upper-level microwave and infrared sounding channels data to be assimilated into HWRF due to a more accurate upper-level background profi le. The track and intensity forecasts produced by the HWRF data assimilation and forecast system with a higher model top are more accurate than those with a lower model top.

  20. Geology of the Spruce Pine District, Avery, Mitchell, and Yancy Counties, North Carolina

    Science.gov (United States)

    Brobst, Donald Albert

    1962-01-01

    The Spruce Pine pegmatite district, a northeastward-trending belt 25 miles long and 10 miles wide, lies in parts of Avery, Mitchell, and Yancey Counties in the Blue Ridge Province of western North Carolina. The most abundant rocks in the district are interlayered mica and amphibole gneisses and schists, all of which are believed to be of Precambrian age. These rocks are cut by small bodies of dunite and associated rocks of Precambrian (?) age, large bodies of alaskite and associated pegmatite of early Paleozoic age, and basaltic and diabasic dikes and sills of Triassic (?) age. The rocks of the district have been weathered to saprolite that is locally 50 feet thick. The major structure in the area is a southwestward-plunging asymmetrical synclinorium that has its steeper limb on the northwest side. Feldspar, muscovite as sheet and scrap (ground) mica, and kaolin from the alaskite and associated pegmatite account for over 90 percent of the total mineral production of the district. Amounts of other pegmatite minerals, including quartz, beryl, columbite-tantalite, rare-earth and uranium minerals are an extremely small part of the mineral resources. Actual or potential products from other rocks are olivine, vermiculite, asbestos, talc, chromium and nickel, soapstone, mica schist, garnet, kyanite, dolomite marble, and construction materials.

  1. The origin of emeralds embedded in archaeological artefacts in Slovenia

    Directory of Open Access Journals (Sweden)

    Albina Kržič

    2013-06-01

    Full Text Available Roman gold jewellery, which was excavated in Ptuj (Poetovio and consists of a necklace, earrings and a braceletwith embedded emeralds, is part of the Slovenian archaeological artefacts collections. Crystallographic characteristics,inclusions, luminous phenomena and geological characteristics were determined in order to establish theorigin of the emeralds. Chemical composition of the emeralds was determined non-destructively using the methodsof proton-induced X-rays and gamma rays (PIXE/PIGE. The results were compared with reference emeraldsfrom Habachtal in Austria and with green beryls from the Ural Mts. Literature data for emeralds from Egypt andmodern-day Afghanistan area were used to interpret the results. Specifically, these sites were known for emeraldsbeing mined for jewellery in Roman times. It was assumed that emeralds from archaeological artefacts originatedfrom Habachtal in Austria, given that this site was the nearest to the place where found. But the emeralds fromthe necklace and earrings in fact came from Egyptian deposits. The origin of emeralds from the bracelet could nothave been determined absolutely reliably due to the lack of comparative materials; they may originate from a site inmodern-day Afghanistan or from Egypt, but certainly not from the same site as the previously mentioned emeraldsin the necklace and earrings.

  2. Structure analysis on synthetic emerald crystals

    Science.gov (United States)

    Lee, Pei-Lun; Lee, Jiann-Shing; Huang, Eugene; Liao, Ju-Hsiou

    2013-05-01

    Single crystals of emerald synthesized by means of the flux method were adopted for crystallographic analyses. Emerald crystals with a wide range of Cr3+-doping content up to 3.16 wt% Cr2O3 were examined by X-ray single crystal diffraction refinement method. The crystal structures of the emerald crystals were refined to R 1 (all data) of 0.019-0.024 and w R 2 (all data) of 0.061-0.073. When Cr3+ substitutes for Al3+, the main adjustment takes place in the Al-octahedron and Be-tetrahedron. The effect of substitution of Cr3+ for Al3+ in the beryl structure results in progressively lengthening of the Al-O distance, while the length of the other bonds remains nearly unchanged. The substitution of Cr3+ for Al3+ may have caused the expansion of a axis, while keeping the c axis unchanged in the emerald lattice. As a consequence, the Al-O-Si and Al-O-Be bonding angles are found to decrease, while the angle of Si-O-Be increases as the Al-O distance increases during the Cr replacement.

  3. Inclusions in topaz from miarolitic pegmatites of the Volodarsk-Volynski Massif (Ukraine)--a Raman spectroscopic study.

    Science.gov (United States)

    Dumańska-Słowik, Magdalena; Wesełucha-Birczyńska, Aleksandra; Natkaniec-Nowak, Lucyna

    2013-05-15

    The differently coloured (colourless, brown-pinkish and blue-pinkish) crystals of topaz from granitic pegmatites of Volodarsk-Volynsky Massif (VVM) have been investigated by scanning electron microscopy (SEM) and Raman microspectroscopy (RS) methods. Topaz (287, 522, 855, 929 cm(-1)), goethite (390 cm(-1)), pyrite (377-379 cm(-1)), marcasite (397 and 331 cm(-1)) and monazite (460 and 970-1070 cm(-1)) were identified as mineral inclusions in analysed crystals. On the basis of RS spectra some of this inclusions contain also organic matter, represented by carbonaceous matter (D-band at ca. 1320-1340 cm(-1) and G-band at ca. 1590-1600 cm(-1)) and liquid simple hydrocarbons consisting of aliphatic and aromatic groups (1240, 1325 and 1420 cm(-1)). Other solid phases found the host topaz, i.e. quartz, orthoclase, very rare minerals (micas) as lepidolite, zinnwaldite and also beryl and rutile, were identified with SEM-EDS analyses. All these mineral inclusions have been formed by post-magmatic, fluid-induced processes, extended from pegmatite to hydrothermal stages of magma crystallization. PMID:23501722

  4. Origin of garnet in aplite and pegmatite from Khajeh Morad in northeastern Iran: A major, trace element, and oxygen isotope approach

    Science.gov (United States)

    Samadi, Ramin; Miller, Nathan R.; Mirnejad, Hassan; Harris, Chris; Kawabata, Hiroshi; Shirdashtzadeh, Nargess

    2014-11-01

    Triassic monzogranites and granodiorites of the Khajeh Morad region in northeastern Iran are cut by two types of garnet-bearing intrusive veins: (1) aplite and (2) granitic pegmatite. The former is composed of quartz, feldspar, muscovite, with minor garnet, biotite, and ilmenite. The latter contains quartz, plagioclase (± quartz and muscovite inclusions), alkali feldspar, and muscovite, with minor amounts of garnet, tourmaline, beryl, columbite, and ilmenite. Garnet in both rock types has MnO > 12 wt.% and CaO pegmatite garnet δ18O values are nearly identical (~ 10.3‰, n = 7, SD = 0.09) and are similar to magmatic garnets in granitoids elsewhere. On the basis of calculated δ18O values for magma (~ 12.5 and 12.6‰) and quartz (~ 13.6‰, n = 7, SD = 0.08) as well as the major and trace element characteristics, we suggest that the Khajeh Morad garnets crystallized from a variably fractionated S-type monzogranitic magma.

  5. $YB_{66} a new soft X-ray monochromator for synchrotron radiation

    CERN Document Server

    Wong, J; Rowen, M; Schäfers, F; Müller, B R; Rek, Z U

    1999-01-01

    For pt.I see Nucl. Instrum. Methods Phys. Res., vol.A291, p.243-8, 1990. YB/sub 66/, a complex boron-rich man-made crystal, has been singled out as a potential monochromator material to disperse synchrotron soft X-rays in the 1-2 keV region. Results of a series of systematic property characterizations pertinent for this application are presented in this paper. These include Laue diffraction patterns and high-precision lattice-constant determination, etch rate, stoichiometry, thermal expansion, soft X-ray reflectivity and rocking-curve measurements, thermal load effects on monochromator performance, nature of intrinsic positive glitches and their reduction. The 004 reflection of YB/sub 66/ has a reflectance of ~3 in this spectral region. The width of the rocking curve varies from 0.25 eV at 1.1 keV to 1.0 eV at 2 keV, which is a factor of two better than that of beryl(1010) in the same energy range, and enables measurements of high-resolution XANES spectra at the Mg, Al and Si K- edges. The thermal bump on the...

  6. Performance and application of a double-crystal monochromator in the energy region 800 less than or equal to hν less than or equal to 4500 eV

    International Nuclear Information System (INIS)

    The performance and application of an ultra-high-vacuum compatible constant-deviation double-crystal monochromator (JUMBO) in operation at SSRL is demonstrated. The monochromator can be operated with any of four pairs of crystals interchangeable in situ. An electronic-maximum-search feedback loop optimizes the intensity of the spatially fixed outgoing beam as the photon energy is scanned. The monochromatic beam is focussed (approx. 1.5 mm x 5 mm) onto the sample by a toroidal mirror. Monochromator crystals of beryl(10 anti 10), InSb(111) and Ge(111) have been tested in the energy regions 800 to 1540 eV, 1690 to 4000 eV and 1930 to 4500 eV, respectively. The performance of these crystals with regard to the resolution, the intensity, the level of scattered light, and the contribution of higher orders have been determined. Various effects arising from a radiation-induced temperature gradient in the monochromator crystals are discussed

  7. Regional background assessment of groundwater wells in the Greater Hudson Hope Area

    International Nuclear Information System (INIS)

    The initial exploration activities for coalbed methane (CBM) development in the Hudson Hope area of British Columbia (BC) have now begun. This baseline survey of water resources was conducted as a result of concerns over the impacts of CBM development on water quality and quantity. Eight environmental monitoring sites were located and water samples were collected to analyze potability, dissolved metals, and extractable petroleum hydrocarbons. Quantity data were collected to measure static water levels as well as to obtain flow measurements on springs and creeks. The study also included a review of surficial and bedrock geology in order to identify aquifers. Risk areas were identified in order to increase monitoring activities at sites requiring higher levels of protection. Risk areas included the Peace River Terrace, which has a large fluvial deposit of gravels and sands susceptible to contamination, and the Beryl Prairie Road Corridor, which has an aquifer that flows over sedimentary bedrock and supplies water to approximately 40 dwellings. 11 refs., 1 tab., 11 figs.

  8. Different periods of uranium and thorium occurrence in Madagascar (1960)

    International Nuclear Information System (INIS)

    In Madagascar, the first typical occurrences of thorium and uranium are about 500 million years old. Previously thorium and uranium were rather concentrated in the granitic and charnockitic zones, chiefly in minerals such as monazite, apatite and zircon. At the end of the Precambrian period, metasomatic granites occur especially in the anticlinal series (Andriba orthite granite). The granitization is followed by the formation of the main pegmatitic areas in the Island with Th-U niobotantalates, uraninite and beryl. The pegmatites are well developed in the synclinal series with a poor migmatization or no migmatization at all. In the same time a large uranium and thorium province with uranothorianite deposits appears within the calcomagnesian series of the Southern part of Madagascar. Later, large amounts of monazite were carried down to the detritic Karroo sediments during tile erosion of the metamorphic precambrian rocks. Monazite has been concentrated again by frequent marine incursions, till the present time. In the medium Karroo, near Folakara, uranium minerals occur in direct relation with carbonaceous material. Finally we must note the uranium occurrence in the pleistocene carbonaceous shales of Antsirabe basin, in contact with crystalline rocks. (author)

  9. L α X-Ray Emission Spectra of Copper Compounds and Alloys

    Science.gov (United States)

    Sugiura, Chikara

    1994-05-01

    With a two-crystal vacuum spectrometer equipped with beryl crystals,the Cu Lα emission spectra in fluorescence have been measuredfor selected copper compounds Cu2O, CuO, CuCl, CuBr, CuI,CuF2, CuCl2, CuBr2, CuF2·2H2O,CuCl2·2H2O and Cu3P, and alloysα-Cu+35%Zn and Cu+2%Be. The measured spectra aregrouped into three classes. The first class comprises the spectraof alloys, which consist of a single broad band similar to thatof Cu metal. The second class includes the spectra of monovalentcopper compounds, which are composed of a prominent peak and itshigh- and low-energy structures. To the third class belong thespectra of divalent copper compounds, which consist of a strongpeak accompanied with a characteristic dip and hump on thehigh-energy side. The Cu Lα emission bands of Cu2O,CuCl and CuBr are compared with available XPS spectra andtheoretical Cu-3d-DOS.

  10. Results of weekly chemical and isotopic monitoring of selected springs in Norris Geyser Basin, Yellowstone National Park during June-September, 1995

    Science.gov (United States)

    Fournier, R.O.; Weltman, U.; Counce, D.; White, L.D.; Janik, C.J.

    2002-01-01

    Each year at Norris Geyser Basin, generally in August or September, a widespread hydrothermal 'disturbance' occurs that is characterized by simultaneous changes in the discharge characteristics of many springs, particularly in the Back Basin. During the summer season of 1995, water samples from eight widely distributed hot springs and geysers at Norris were collected each week and analyzed to determine whether chemical and isotopic changes also occurred in the thermal waters at the time of the disturbance. In addition, Beryl Spring in Gibbon Canyon, 5.8 km southwest of Norris Geyser Basin, was included in the monitoring program. Waters discharged by four of the monitored hot springs and geysers appear to issue from relatively deep reservoirs where temperatures are at least 270 C and possibly higher than 300 C. At the time of, and for several days after, the onset of the 1995 disturbance, the normally neutral-chloride waters discharged by these four features all picked up an acid-sulfate component and became isotopically heavier. The acid-sulfate component appears to be similar in composition to some waters discharged in 100 Spring Plain that issue from subsurface regions where temperatures are in the range 170-210 C. However, the two monitored springs that discharge acid-chloride-sulfate waters in the 100 Spring Plain region did not show any significant chemical or isotopic response to the annual disturbance. Beryl Spring, and two neutral-chloride hot springs at Norris that appear to draw their water from reservoirs where temperatures are 250 C or less, also did not show any significant chemical or isotopic response to the annual disturbance. After the start of the annual disturbance, chloride concentrations in water sampled from Double Bulger Geyser in the Back Basin increased from about 800 ppm to about 1500 ppm, nearly twice as high as any previously reported chloride concentration in a thermal water at Yellowstone. The isotopic composition of that water

  11. Thermal equation of state of natural tourmaline at high pressure and temperature

    Science.gov (United States)

    Xu, Jingui; Kuang, Yunqian; Zhang, Bo; Liu, Yonggang; Fan, Dawei; Li, Xiaodong; Xie, Hongsen

    2016-05-01

    Synchrotron-based in situ angle-dispersive X-ray diffraction experiments were conducted on a natural uvite-dominated tourmaline sample by using an external-heating diamond anvil cell at simultaneously high pressures and temperatures up to 18 GPa and 723 K, respectively. The angle-dispersive X-ray diffraction data reveal no indication of a structural phase transition over the P-T range of the current experiment in this study. The pressure-volume-temperature data were fitted by the high-temperature Birch-Murnaghan equation of state. Isothermal bulk modulus of K 0 = 96.6 (9) GPa, pressure derivative of the bulk modulus of K0^' } = 12.5 (4), thermal expansion coefficient of α 0 = 4.39 (27) × 10-5 K-1 and temperature derivative of the bulk modulus ( ∂K/∂T) P = -0.009 (6) GPa K-1 were obtained. The axial thermoelastic properties were also obtained with K a0 = 139 (2) GPa, K_{a0}^' } = 11.5 (7) and α a0 = 1.00 (11) × 10-5 K-1 for the a-axis, and K c0 = 59 (1) GPa, K_{c0}^' } = 11.4 (5) and α c0 = 2.41 (24) × 10-5 K-1 for the c-axis. Both of axial compression and thermal expansion exhibit large anisotropic behavior. Thermoelastic parameters of tourmaline in this study were also compared with that of the other two ring silicates of beryl and cordierite.

  12. Pegmatito Gentil (Mendes Pimentel, MG e suas paragêneses mineralógicas de fosfatos raros Gentil Pegmatite (Mendes Pimentel, MG and their rare phosphate mineral assemblages

    Directory of Open Access Journals (Sweden)

    Mario Luiz de Sá C. Chaves

    2008-06-01

    Full Text Available Centenas de corpos pegmatíticos na região nordeste de Minas Gerais produzem minerais gemológicos e de coleção, muitos desses corpos possuindo afinidades com determinada espécie, grupo ou classe mineral. O Pegmatito Gentil em Mendes Pimentel, ora descrito, notabiliza-se por sua assembléia de minerais fosfáticos, a maior parte dos quais raros ou raríssimos na natureza. A associação mineral identificada inclui microclínio, quartzo, muscovita, almandina-espessartita, berilo e trifilita como fosfato primário, que foi alterado formando uma extensa paragênese de espécies secundárias. Entre essas, destacam-se brazilianita, frondelita, gormanita, huréaulita, lazulita, litiofilita, purpurita, reddingita, woodhouseíta, zanaziíta e, recentemente descrita nesse corpo, a matioliíta.Hundreds of pegmatitic bodies occur in the northern region of the State of Minas Gerais, several of these bodies producing gemologic and collection minerals. Such pegmatites are known by the mineral affinity with certain minerals species, groups or classes. The Gentil Pegmatite (Mendes Pimentel county is characterized by the phosphatic mineral assemblage, and some of these minerals are rare or very rare in nature. Primary species are microcline, quartz, muscovite, almandine-espessartine, beryl, and triphylite as the main phosphate that was altered to an extensive paragenesis of secondary phosphates. In this list are noted brazilianite, frondelite, gormanite, hureaulite, lazulite, lithiophilite, purpurite, reddingite, woodhouseite, zanaziite, and matioliite, a species recently described in the Gentil Pegmatite.

  13. Rare-element granitic pegmatite of Miocene age emplaced in UHP rocks from Visole, Pohorje Mountains (Eastern Alps, Slovenia): accessory minerals, monazite and uraninite chemical dating

    Science.gov (United States)

    Uher, Pavel; Janák, Marian; Konečný, Patrik; Vrabec, Mirijam

    2014-04-01

    The granitic pegmatite dike intruded the Cretaceous UHP rocks at Visole, near Slovenska Bistrica, in the Pohorje Mountains (Slovenia). The rock consists mainly of K-feldspar, albite and quartz, subordinate muscovite and biotite, while the accessory minerals include spessartine-almandine, zircon, ferrocolumbite, fluorapatite, monazite- (Ce), uraninite, and magnetite. Compositions of garnet (Sps48-49Alm45-46Grs + And3-4 Prp1.5-2), metamict zircon with 3.5 to 7.8 wt. % HfO2 [atom. 100Hf/(Hf + Zr) = 3.3-7.7] and ferrocolumbite [atom. Mn/(Mn + Fe) = 0.27-0.43, Ta/(Ta + Nb) = 0.03-0.46] indicate a relatively low to medium degree of magmatic fractionation, characteristic of the muscovite - rare-element class or beryl-columbite subtype of the rare-element class pegmatites. Monazite-(Ce) reveals elevated Th and U contents (≤11 wt. % ThO2, ≤5 wt. % UO2). The monazite-garnet geothermometer shows a possible precipitation temperature of ~495 ± 30 °C at P~4 to 5 kbar. Chemical U-Th-Pb dating of the monazite yielded a Miocene age (17.2 ± 1.8 Ma), whereas uraninite gave a younger (~14 Ma) age. These ages are comtemporaneous with the main crystallization and emplacement of the Pohorje pluton and adjacent volcanic rocks (20 to 15 Ma), providing the first documented evidence of Neogene granitic pegmatites in the Eastern Alps. Consequently, the Visole pegmatite belongs to the youngest rare-element granitic pegmatite populations in Europe, together with the Paleogene pegmatite occurrences along the Periadriatic (Insubric) Fault System in the Alps and in the Rhodope Massif, as well as the Late Miocene to Pliocene pegmatites in the Tuscany magmatic province (mainly on the Island of Elba).

  14. Rare metal granites and related rocks of the Ukrainian shield

    Directory of Open Access Journals (Sweden)

    Esipchuk, K.Ye.

    1993-12-01

    Full Text Available Two rare metal leucocratic granites, Perga and Kamennaya complexes, can be distinquished on the Ukrainian shield. The Perga complex consists of medium- and coarse grained, mainly porphyric, biotite, riebeckite and aegirine granites, granite porphyries, microclinites and albitites with rare metal mineralization (genthelvite, phenacite, tantalite, cassiterite and wolframite etc.. Granites from several stocks (up to 30 km2 in the northwestern part of the shield, situated along the fracture zone, restricted the large Korosten pluton of rapakivi granites to the northwest. The age of these granites (Pb-Pb and U-Pb methods on zircon and monazite practically coincide with the age of rapakivi granites being 1750 Ma. Within the Korosten complex of rapakivi granites we consider that zinnwaldite granites, which are characterized by fluorite and topazine mineralization, represent the final phase of pluton. These granites differ from the Perga ones by their low content of rare metals. The Kamennaya Mogila complex lies in the southeastern part of the Ukrainian shield. It consists of biotite and muscovite-biotite, medium- and coarse-grained (also porphyric, and occasionally greisining granites with rare metal mineralization (cassiterite, columbite, molybdenite, wolframite and beryl. Granites form several stocks (5-30 km2 situated 10-30 km to the west-northwest of the South-Kalchik gabbro-syenite-granite pluton. Granitoids in both of these complexes have similar isotopic ages (1800 Ma. Leucocratic subalkaline granites (the Novoyanisol type are known within the pluton itself, occupying an intermediate position between the above mentioned in terms of mineral and geochemical composition. The gabbro-syenite-granite formation of the Nearazov region has a substantial similarity to the anorthosite-rapakivi-granite formation. In this respect the relation of each of them to rare metal granites is rather remarkable. This relation is, most probably, not only spatial, but

  15. Estimation of steady-state and transcient power distributions for the RELAP analyses of the 1963 loss-of-flow and loss-of-pressure tests at BR2.

    Energy Technology Data Exchange (ETDEWEB)

    Dionne, B.; Tzanos, C. P. (Nuclear Engineering Division)

    2011-05-23

    To support the safety analyses required for the conversion of the Belgian Reactor 2 (BR2) from highly-enriched uranium (HEU) to low-enriched uranium (LEU) fuel, the simulation of a number of loss-of-flow tests, with or without loss of pressure, has been undertaken. These tests were performed at BR2 in 1963 and used instrumented fuel assemblies (FAs) with thermocouples (TC) imbedded in the cladding as well as probes to measure the FAs power on the basis of their coolant temperature rise. The availability of experimental data for these tests offers an opportunity to better establish the credibility of the RELAP5-3D model and methodology used in the conversion analysis. In order to support the HEU to LEU conversion safety analyses of the BR2 reactor, RELAP simulations of a number of loss-of-flow/loss-of-pressure tests have been undertaken. Preliminary analyses showed that the conservative power distributions used historically in the BR2 RELAP model resulted in a significant overestimation of the peak cladding temperature during the transient. Therefore, it was concluded that better estimates of the steady-state and decay power distributions were needed to accurately predict the cladding temperatures measured during the tests and establish the credibility of the RELAP model and methodology. The new approach ('best estimate' methodology) uses the MCNP5, ORIGEN-2 and BERYL codes to obtain steady-state and decay power distributions for the BR2 core during the tests A/400/1, C/600/3 and F/400/1. This methodology can be easily extended to simulate any BR2 core configuration. Comparisons with measured peak cladding temperatures showed a much better agreement when power distributions obtained with the new methodology are used.

  16. Chemistry characterization and samples beryllium process impurity determination; Caracterizacao quimica e determinacao de impurezas de amostras de processo de berilio

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Leonel Mathry de

    1992-12-01

    Brazil is the greatest world producer of beryl (3 Be O.Al{sub 2}O{sub 3}.6SiO{sub 2}) and has recently begun to produce beryllium compounds by means of a pilot plant constructed at Governador Valadares city (Minas Gerais - Brazil). The aim of this work was the determination of trace level impurities and macro constituents in the tenth % range to support analytical control process of plant production and characterization of beryllium compounds. The impurities separations and purification process was developed by two steps procedure. The first one using EDTA complexation has separated and reduced some impurities to less than 1 {mu}g/ml level. In the second one it was used a chelating resin (Chelex 100) and the separation efficiency was about 75 to 97 % related with the element tested. High pure berylium oxide standard was obtained from purification of Be(OH)2. The R X fluorescence presented only traces of Cu and Si < 1 % Fe and Mn, Zn, Ca, Al, Na and S were completely removed. The beryllium content was determined by direct atomic emission spectroscopy in argon plasma (Dcp) and compared with classic gravimetric method as Be O. The results were in agreement (49,2+/-0,2 % and 48,3+/-0,1 % respectively) between 95 % of confidence. A low temperature gravimetric method for beryllium determination was also studied using Oxine with microwave furnace. A total of 24 elements including macro and trace level were determined by Dcp and/or spectrophotometric methods. The Be/B separation was studied using anionic resin in poly alcohols medium. A more detailed study of equilibrium conditions is necessary. This work was realized at Laboratorio de Analise Mineral (LAM) of Comissao Nacional de Energia Nuclear - Rio de Janeiro (CNEN). (author)

  17. Leachability characteristics of beryllium in redmud waste and its stabilization in cement

    International Nuclear Information System (INIS)

    More than 70% of the beryl ore processed by the Beryllium Metal Plant at the BARC Vashi Complex ends up as redmud waste. The presence of significant quantities (0.4 to 0.8%) of beryllium in the redmud qualifies it as hazardous requiring safe handling, storage and disposal. The waste also contains 0.09% of water soluble fluoride. The various standard protocol of procedures were employed to estimate the leachability of beryllium from redmud for both short term and long term periods. Nearly 50% of beryllium present in redmud is leachable in water. We have tried the stabilization of redmud using portland cement. The proportion of redmud to cement was in the ratio of 1:1, 1:2 and 1:4. The blocks were cast, cured and used in the leachability experiments using standard protocols as above. The results of the TCLP test gave the levels of beryllium well below the standard limits in the TCLP extract of cement stabilized waste indicating the suitability of stabilization of redmud with cement whereas that of raw waste (redmud) are much higher than the prescribed limits. The total leach percent of beryllium in 1:2 block is 0.05% over period of 164 days whereas 1:1 and 1:4 gave a leach percent of 0.26 and 0.15% respectively. The DLT results indicate, diffusion controlled release of beryllium from the cement stabilized redmud blocks. The effective diffusion coefficient of beryllium obtained from the modelling study is 10 orders of magnitude less than the molecular diffusion coefficient of beryllium indicating the effectiveness of cement stabilization. From the detailed experiments performed, it is felt that 1:2 proportion of redmud and cement will be the best suited option for stabilization of redmud waste. The 1:1 proportion of redmud to cement mixture which could not be cast into compact cement blocks also exhibited very low leachability characteristics similar to 1:2 and 1:4 and can be be favourably considered for stabilization in case of space constraints at storage sites. The

  18. Proximal and distal styles of pegmatite-related metasomatic emerald mineralization at Ianapera, southern Madagascar

    Science.gov (United States)

    Andrianjakavah, Prosper Rakotovao; Salvi, Stefano; Béziat, Didier; Rakotondrazafy, Michel; Giuliani, Gaston

    2009-10-01

    . Emerald composition was controlled by the chemistry of the host rock. The presence of carbonate mineral inclusions in the emeralds and the high F-activity indicated by elevated F-contents in newly formed minerals suggest transport of Be as a fluoride-carbonate complex. It seems likely that beryl formation was triggered by precipitation of F-rich phlogopite, which removed the complexing ligand from the fluid.

  19. Geological setting and timing of the cassiterite vein type mineralization of the Kalima area (Maniema, Democratic Republic of Congo)

    Science.gov (United States)

    Dewaele, S.; Muchez, Ph; Burgess, R.; Boyce, A.

    2015-12-01

    The Central African Mesoproterozoic Karagwe-Ankole belt in the Great Lakes area (DRCongo, Rwanda, Burundi, Uganda and Tanzania) forms a metallogenic province that hosts a variety of granite-related mineralization, which contains cassiterite, columbite-tantalite, wolframite/ferberite, spodumene and beryl. The Kalima area in the Maniema province of the DRCongo forms one of the most important areas for cassiterite mineralization in the eastern part of the DRCongo, even after many decades of exploitation. The mineralization dominantly consists of quartz veins that are hosted in Mesoproterozoic metasediments at the contact with granitic rocks of the Kalima granite (Avuanga and Yubuli) or directly crosscutting these granitic rocks (Atondo). Only limited - and mainly unmineralized pegmatites - have been described in the Lutshurukuru area. Mineralized quartz veins - and some granite bodies - intruded following the regional tectonic foliation or existing fracture zones, confirming the late-to post-tectonic origin of the fertile granite system. The emplacement of the quartz veins resulted in an alteration of the metasedimentary and granitic host-rocks, mainly resulting in muscovitization, tourmalinization and silicification. Cassiterite itself formed relatively late during vein formation and is associated with muscovite in fractures in or along the margins of the quartz veins. 40Ar-39Ar age dating of muscovite of an unmineralized pegmatite from the Lutshurukuru area gave an excellent plateau age of 1024 ± 5.5 Ma, while the muscovite associated with mineralization gave plateau ages of 986 ± 5.3 Ma for the Atondo deposit and 992.4 ± 5.4 Ma for the Yubuli deposit. The rather large spread in ages between the supposed parental granite/pegmatite and quartz veins is interpreted to reflect different magmatic events in the evolution of a composite granite system, starting at ∼1020 Ma and ending with mineralized quartz vein formation at ∼990 Ma. The latter age corresponds with

  20. Tertiary LCT and NYF pegmatites of the central Alps

    Science.gov (United States)

    Guastoni, Alessandro; Pennacchioni, Giorgio

    2014-05-01

    A large field (about 100 km in E-W length and 15 km in N-S thickness) of Oligocene pegmatites extends in the central Alps from the Bergell pluton (to the east) to the Ossola Valley (to the west) within the Alpine nappes north of the Periadriatic Lineament. The pegmatite field geographically overlaps (i) the highest temperature domain of the Lepontine Barrovian metamorphic dome, and (ii) the zone of Alpine migmatization. Most pegmatites have a simple mineralogy consisting of K-feldspar, quartz and muscovite, but a minor amount (pegmatite bulk rock, rock-forming and accessory minerals allows the distinction of different pegmatite populations ranging from NYF (niobium, yttrium, fluorine) to LCT (lithium, cesium, tantalum) pegmatites, or mixed LCT-NYF ones. Actually, LCT pegmatites of the Central Alps did not reach a high degree of geochemical evolution. In the Codera Valley (on the western side of the Bergell pluton) LCT and NYF pegmatites are respectively hosted in tonalites and granodiorites; these pegmatites include the most evolved types which contain Mn-fluorelbaite, Mn-phosphates, pink-beryl and Cs-Rb-rich feldspar. From the structural point of view 2 main types of pegmatites can be distinguished: (i) pegmatites that were involved in ductile deformation, and (ii) pegmatite crosscutting the ductile structures of the SSB. Many pegmatites from Codera Valley belong to the first structural type: they were at emplaced at relatively high ambient temperatures (> 450 °C) and locally show pervasive recrystallization of quartz. More to the east (Mesolcina and Bodengo Valleys) the main set of pegmatites crosscut the ductile deformation structures of the SSB, but the area also includes an earlier generation of boudinaged and folded dykes. The undeformed pegmatites from this area may contain large miarolitic pockets. There is no systematic difference in mineralogy and geochemistry between the 2 structural types of pegmatites. Structural data and the few existing radiometric

  1. Chemistry and radiation effects of thorite-group minerals from the harding pegmatite, Taos County, New Mexico

    International Nuclear Information System (INIS)

    Dark brown and yellow thorites, with compositions extending the range of natural solid solution for the zircon structure type, occur as 0.5- to 2-cm grains in the quartz zone, cleavelandite unit (replacing the beryl zone), quartz-lath spodumene zone, and microcline-spodumene zone of the Harding pegmatite, Taos County, New Mexico. Electron-micro-probe analyses (wt%) give the following for thorites from the cleavelandite unit: 2.9-19.6 P2O5, 6.4-16.5 V2O5, 0.2-1.2 As2O5, 2.6-7.7 SiO2, 41-57 ThO2, 0.0-0.9 UO2, 0.1-2-9 Y2O3, 0.1-6.5 REE2O3, 0.0-4.7 Bi2O3, 5.8-8.4 CaO, 0.1-0.6 PbO, and 0.4-1.7 F. In contrast, yellow thorites from the quartz zone contain (wt%) 17-20 SiO2, 36-65 ThO2, 3-20 UO2, 0.4-0.8 Al2O3, 0.3-0.6 Y2O3, 0.2-0.6 REE2O3, 0.6-1.0 Bi2O3, 0.8-1.3 CaO, 3-17 PbO, and 0.0-0.9 F. Low totals of the microprobe analyses probably indicate the presence of 7-12 wt% H2O, in agreement with TGA. Infrared spectra confirm the presence of molecular water and are consistent with the presence of mixed types of hydroxyl species. Both varieties of thorite are partially recrystallized. In the brown variety, the degree of crystallinity correlates with increasing substitution of P, V, and Ca for Si and Th. Calculated alpha-event dose (4-12 x 1017 α/mg) are greater than the damage saturation dose (∼1 x 1016 α/mg), but substantial crystallinity is present. The energy barrier to recrystallization of alpha-decay-damaged thorite enriched in P and V is inferred to be lower than for ideal thorite or U-rich microlites from the microcline-spodumene zone

  2. Graphical representations of the chemistry of garnets in a three-dimensional MATLAB based provenance plot

    Science.gov (United States)

    Knierzinger, Wolfgang; Palzer, Markus; Wagreich, Michael; Meszar, Maria; Gier, Susanne

    2016-04-01

    A newly developed, MATLAB based garnet provenance plot allows a three-dimensional tetrahedral representation of the chemistry of garnets for the endmembers almandine, pyrope, spessartine and grossular. Based on a freely accessible database of Suggate & Hall (2013) and additional EPMA-data on the internet, the chemistry of more than 2500 garnets was evaluated and used to create various subfields that correspond to different facies conditions of metapelitic, metasomatic and metaigneous rocks as well as granitic rocks. These triangulated subfields act as reference structures within the tetrahedron, facilitating assignments of garnet chemistries to different lithologies. In comparison with conventional tenary garnet discrimination diagrams by Mange & Morton (2007), Wright/Preston et al. (1938/2002) and Aubrecht et al. (2009), this tetrahedral provenance plot enables a better assessment of the conditions of formation of garnets by reducing the overlapping of certain subfields. In particular, a clearer distinction between greenschist facies rocks, amphibolite facies rocks and granitic rocks can be achieved. First applications of the tetrahedral garnet plot provided new insights on sedimentary processes during the Lower Miocene in the pre-Alpine Molasse basin. Bibliography Aubrecht, R., Meres, S., Sykora, M., Mikus, T. (2009). Provenance of the detrital garnets and spinels from the Albian sediments of the Czorsztyn Unit (Pieniny Klippen Belt , Western Carpathians, Slovakia). In: Geologica Carpathica, Dec. 2009, 60, 6, pp. 463-483. Mange, M.A., Morton, A.C. (2007). Geochemistry of Heavy Minerals. In: Mange, M.A. & Wright, D.T.(2007).Heavy Minerals in Use, Amsterdam, pp. 345-391. Preston, J., Hartley, A., Mange-Rajetzky, M., Hole, M., May, G., Buck, S., Vaughan, L. (2002). The provenance of Triassic continental sandstones from the Beryl Field, northern North Sea: Mineralogical, geochemical and sedimentological constraints. In: Journal of Sedimentary Research, 72, pp. 18

  3. Trisomy 13 (Patau Syndrome

    Directory of Open Access Journals (Sweden)

    Masoud Poureisa

    2009-01-01

    picture and survival is usually longer. "nReference: Beryl R.Benacerrafe, M.D; Ultrasound of fetal syndromes: trisomy 13 (316- 321  

  4. Trisomy 18 (Edwards Syndrome

    Directory of Open Access Journals (Sweden)

    Masoud Poureisa

    2009-01-01

    unable to unclench their hands. Heredity This is an autosomal trisomic syndrome. Natural history and outcome Fetuses with trisomy 18 often die in utero. Ninety percent of live- borns with this abnormality die in the first year of life. The 10% who survive are profoundly mentally retarded and handicapped. Reference: Beryl R Benacerrafe, M.D; Ultrasound of fetal syndromes:  (322 - 324    

  5. Main activities in Kazakhstan aimed to substantiate ITER and demo reactors safety

    International Nuclear Information System (INIS)

    . At the same time the experiments on determination of reflectivity of beryllium and its alloys (titanium, beryl lide, for sample) in vacuum and under steam oxidation would be carried out. Finally so produced mock-ups would be tested with respect to its interaction with steam. The test temperature will be up to 1200 degree C. Also irradiation tests on in-pile saturation of beryllium with deuterium would be carried out. (author)

  6. Mineralogía y geoquímica de las micas en las pegmatitas Santa Elena y El Peñón, Provincia Pegmatítica Pampeana, Argentina

    Directory of Open Access Journals (Sweden)

    Miguel A. Galliski

    1999-07-01

    of Pampean Pegmatite Province. The micas are from two possible cogenetic rare-element pegmatites: Santa Elena, a complex-type, petalite subtype pegmatite, and El Peñón, a beryl-type, beryl-columbite-phosphate subtype pegmatite. The micas are muscovite, lithian muscovite, mixed forms and lepidolite. The muscovite s.I. has 2 M, structure and chemistry with comparatively low contents of Mn, Li, Rb, Cs, Ti and Y; one specimen could be classified as a 'rose muscovite'. The lepidolite and mixed forms have 2 M, dominant polytypism with some scarce X-ray reflections of 1 M or 2 M, polytypes. They are higher in SiO2, MnO, CaO, Li2O, Rb2O, Cs, Ti, Y and P. Li2O ranges between 3,71 and 4,73%, and Rb2O from 0,29 to 2,53%. The geochemical evolution of the micas, illustrated by K/Rb versus lithium, manganeso, cesium, thallium and ytrium diagrams, shows a differentiation trend similar to micas from other LCT pegmatite fieids. The inferred crystallization path has evolved approximately around 2-3 kbar and 350-400ºC, in the stability field of spodumene, in a H2O-saturated environment, under increasing HF, KF and LiF activities.

  7. Mapping contact metamorphic aureoles in Extremadura, Spain, using Landsat thematic mapper images

    Science.gov (United States)

    Rowan, L.C.; Anton-Pacheco, C.; Brickey, D.W.; Kingston, M.J.; Payas, A.

    1987-01-01

    studies, confirmed the presence of more extensive aureoles than shown in published geologic maps; few misclassified areas were noted. Additional plowed fields consisting of exposed contact metamorphic soil were mapped digitally in an August 1985 TM scene. Subsequently, this approach was used to map two 1-km-wide linear zones of contact metamorphosed rock and oil in the San Nicolas-Sn-W Mine area, which is located approximated 125 km southeast of the Caceras study area. Exposures of granite in the San Nicolas area are limited to a few unaltered granitic dikes in the mine and a small exposure of unaltered pegmatite-bearing granite in a quarry about 1.5 km west of the mine. The present of coarsely crystalline biotite and beryl in the granite in the quarry and of contact metamorphosed slate up to 2.5 km from the nearest granite exposure suggest that only the apical part of a pluton is exposed in the quarry and that a larger, shallowly buried body is probably present. These results indicate that potential application of TM image analysis to mineral exploration in lithologically similar areas that are cultivated in spite of poor rock exposures.

  8. Study on Chemical Compositions and Infrared Absorption Spectra of Natural and Synthetic Emeralds%天然祖母绿与合成祖母绿的成分及红外吸收光谱研究

    Institute of Scientific and Technical Information of China (English)

    申柯娅

    2011-01-01

    祖母绿是一种高档名贵的宝石,其矿物学名称为绿柱石,化学成分为铍铝硅酸盐.鉴别天然祖母绿和人工合成祖母绿,已成为祖母绿宝石鉴定中的一个重要课题.文章采用常规宝石学研究方法、激光剥蚀-电感耦合等离子体质谱法和红外光谱技术对天然祖母绿(包括哥伦比亚祖母绿和巴西祖母绿)、合成祖母绿(包括助熔剂法合成祖母绿和水热法合成祖母绿)样品进行了系统的分析和研究.结果表明,天然祖母绿与合成祖母绿的主要致色微量元素Cr的含量越高,祖母绿的绿色越浓艳;天然祖母绿与合成祖母绿的红外吸收光谱特征具有明显的差异;根据祖母绿中是否含水、水的赋存状态以及氯的吸收峰,可作为准确鉴别天然祖母绿和合成祖母绿的重要依据.等离子体质谱法化学成分分析不能确定祖母绿是天然形成还是人工合成,需在常规宝石学检测的基础上,综合研究祖母绿的红外吸收光谱特征及内含物特征,才能准确地鉴别天然祖母绿、水热法合成祖母绿和助熔剂法合成祖母绿.%As a top-grade and rare gemstone, emerald is a variety of the mineral beryl with the chemical composition Be3 Al2 (SiO3) 6. It is a significant research project to identify natural emerald as opposed to synthetic emerald. The routine gemological methods, laser ablation-inductively coupled plasma mass spectrometry ( LA-ICP-MS) and Fourier Transform Infrared Spectroscopy (FTIR) absorption techniques were used to study natural emeralds from Colombia and Brazil and synthetic emeralds made by flux-grown and hydrothermal synthetic methods. The green color of emerald was closely related to the concentration of the trace element Cr( Ⅲ). The infrared absorption spectra characteristics indicated obvious differences between natural and synthetic emeralds. This technique can provide important information for identifying natural and synthetic emeralds, combined

  9. Silica enrichment, graphic granite and aquamarine growth: a new exploration guide

    Directory of Open Access Journals (Sweden)

    A. BHASKARA RAO

    2002-09-01

    Full Text Available Granitic pegmatites are traditionally known to contain graphic, perthitic and myrmekitic intergrowths related to quartz and K- and Na- feldspars. They are further considered to characterise the pegmatite types distinguishing them from the granites and other related plutonic rock types. Graphic granite is accepted also as a synonym to granitic pegmatite. Systematic studies, by the author and colleagues, on the granitic pegmatite gem deposits have permitted the definition of two aquamarine gem provinces in ENE Brazil, one in the NeoProterozoic and the other in the Archaean sequences. Potash feldspars in the pegmatites in the former show perthitic intergrowths, whereas in the latter graphic intergrowth dominates with anomalously coarse centimetric quartz along the cleavages of K-feldspar. Several granitic pegmatites hosted in Archaean complex, in Lages Pintadas Aquamarine Province, Santa Cruz, RN State, present this texture-structure. Graphic intergrowth is attributed to the eutectic crystallization, succeeded by hydrothermal fluids with silica enrichment permitting the growth through diffusion and nucleation of quartz and along cleavages of potash feldspar. In the Archaean terrain, the abundance of recycled chert forming metapsammitic migmatites traversed by numerous quartz veins and coarse graphic granites, has contributed to the growth of beryl and also the aquamarines.Pegmatitos graníticos são tradicionalmente conhecidos por terem intercrescimentos gráficos, pertíticos e mirmequíticos, relacionados a quartzo e feldspatos potássicos e sódicos. Também são considerados para caracterizar os tipos de pegmatitos, distinguindo-os dos granitos e outros tipos de rochas plutônicas relacionadas. Granito gráfico é aceito como sinônimo do pegmatito granítico. Estudos sistemáticos, do autor e seus colegas, sobre depósitos de pegmatitos graníticos de gemas permitiram a definição de duas províncias de gemas águas marinhas no ENE do Brasil

  10. MINERALIZATION POTENTIALS OF PEGMATITES IN THE NASARAWA AREA OF CENTRAL NIGERIA

    Directory of Open Access Journals (Sweden)

    Akintola O. F

    2008-12-01

    barren, Be-, Li-Be, and Li-Cs-Be-Ta types. Comparably low Nb/Ta ratios in the late albites and amblygonites indicate the paragenesis of theseminerals with the tantalumores in themiddle/inner zones of the complexmineralized pegmatites. While the Be-, and Li-Be-types are highly prospective for gem tourmaline, beryl and 213 Accepted for publication: November 4th, 2008. columbite; themost evolved pegmatites in this area are good candidates for tantalite, amblygonite-montebrasite, and probably pollucite prospecting/mining. 

  11. Design and development of a high energy photo-electron spectroscopy beamline on Indus-2 synchrotron radiation source

    International Nuclear Information System (INIS)

    We report on the design and development of a high energy x-ray photo-electron spectroscopy (XPS) beamline for one of the bending magnets (BM-6) at the 2.5 GeV, 3 rd generation Indus-2 synchrotron radiation (SR) source under commissioning at the Raja Ramanna Centre for Advanced Technology, Indore. The beamline (BL) extends up to 40 m in length, and has been designed based on certain criteria such as its working energy range (0.8 - 15.0 keV), the resolution (∼ 10-4), the flux throughput (1010-1011), and the requirement of a focused beam at the sample position. Two pairs of identical crystals in the (+1, -1) double crystal monochromator (DCM) geometry, based on beryl (10i0) and Si (111) reflections with their intrinsic resolution of ∼ 10-4 have been chosen to respectively cover the lower (0.8-2.0 keV) and higher energy (2 - 15.0 keV) ranges of the BL. The DCM has been placed at a distance of 30.0 m from the BM source. The effect of pitch (ΔΘP) and roll errors (ΔΘR) of the DCM on the vertical and horizontal shifts in the exit beam has been evaluated and minimized to acceptable values (ΔΘP R < 2 μrad) that correspond to shifts of less than 20 % of the beam width at the sample position. Sagittal focusing has been achieved by bending the 2 nd Si crystal of the DCM in the sagittal direction. A mirror has been placed at 20.0 m from the BM source. The toroidal surface of the mirror substrate (1.2 m long Si crystal) is coated with a thin film of Pt metal (∼ 50 nm), and held at a grazing angle of 9.0 μrad so that it provides high reflectivity in a much wider energy range from 0.8 to 8.0 keV. The effect of mirror surface imperfections, such as the roughness and figure error, on the spot size at its focal position has been evaluated and optimized using a ray-trace program SHADOW. The optimum value for the roughness is found to be 3.0 A, while those for figure errors are found to be 2.0 and 20.0 μrad in the meridional and sagittal directions, respectively. Further

  12. 铸瓷贴面在前牙美容修复中的临床效果观察%Observation on the effect of ceramic faced in the repair of anterior teeth beauty

    Institute of Scientific and Technical Information of China (English)

    陈艳青

    2013-01-01

    Objective To study the clinical effect of ceramic cover anterior on teeth beauty.Methods 138 teeth in 34 patients with dental fluorosis were divided into two groups,the control group (69 teeth in 16 patients) was given traditional PFM cover repair,the treatment group (69 teeth in 18 patients) was given ceramic cover,they were followed up for three years.The teeth remaining rate and patient satisfaction were compared,the match color,edge fit,healthy gums,restoration integrity were compared according to the Ryge standard.Results Teeth remaining rate in treatment group was 95.7%,which was significantly higher than control group (P < 0.05).The patient satisfaction was 94.4% in treatment group and 87.5% in the control group,the difference was significant (P < 0.05).The match color,edge coloring,healthy gums and teeth sensitivity were not different between the two groups (P > 0.05).The restoration integrity and marginal fit of treatment group was better than control group (P < 0.05).Conclusion The clinical effect of ceramic faced in the anterior teeth beauty repair,especially in the repair of dental fluorosis is remarkable,and the remaining teeth rate higher,repair,dental restoration integrity and marginal fit is significantly better than that of resin repair,patient satisfaction is higher,the water area from non-beryl popularization and application.%目的 研究铸瓷贴面在前牙美容修复中的临床效果.方法 将34例(138牙)氟斑牙患者随机分为两组,对照组16例(69牙)采用传统烤瓷贴面修复,治疗组18例(69牙)采用铸瓷贴面技术进行修复,随访3年,记录并比较两组患者的牙齿存留率及患者满意度,并采用改良Ryge标准对两组患者牙齿的颜色匹配、边缘密合度、牙龈健康、修复体完整度等指标进行评价.结果 3年后治疗组患者牙齿存留率为95.7%,明显高于对照组的89.9%,差异有统计学意义(P<0.05);治疗组患者满意度为94.4%,对照组为87

  13. Geología, mineralogía y geoquímica de la pegmatita Las Cuevas, San Luis Geology, Mineralogy and Geochemistry of Las Cuevas pegmatite, San Luis.

    Directory of Open Access Journals (Sweden)

    Viviana A Martínez

    2011-12-01

    interpretation of the geology, mineralogy and geochemistry of the Las Cuevas pegmatite, Conlara pegmatitic district, Sierra de San Luis, Argentina. This ore deposit belongs to the Rare-Element class, REL-Li subclass, complex type, spodumene-subtype of granitic pegmatites. it is a tabular bodie trending to the northwest, with dips ranging from vertical to subhorizontal. The host-rocks of the pegmatite are usually quartz-micaceous schists. The depth of emplacement was in the ductile to brittle transition domain, possibly ranging between 7 and 12 km. The intrusion of the pegmatite was forced, producing secondary folding in the host rock and enclosing metric-sized xenoliths. The emplacement took place during the Eopaleozoic, shortly after the regional metamorphic peak of the Famatinian Cycle. The pegmatite and its host-rock were deformed by the late tectonism belonging to the Ocloyic phase. Eight zones of different mineral association, texture and setting have been identified in this pegmatite. The mineralogy comprises: quartz, microcline, spodumene, albite, muscovite, apatite, beryl, schörl, zircon, garnet, columbite-(Mn, tantalite-(Mn, pyrochlore and microlite group minerals, ambligonite-montebrasite, triphylite-litiophilite, elbaite, eucriptite, lepidolite, bismuthinite, pyrite, huréaulite, phosphosiderite, beraunite, rockbridgeite, stewartite, bismutite, ferric oxides, manganese oxides, and mitridatite.The processes of pegmatitic differentiation, indicated by the chemical composition of trace elements in K-feldspar and muscovite, are comparable and do not differ from the known paths of similar world- and argentinian- pegmatites of this type showing lineal fractionation trends. Besides, the individual analysis shows a lineal differentiation, in some cases with an overprint between the samples of different zones, resulting from changes in the physico-chemical conditions of cristalization. Based on the muscovite geochemistry, Las Cuevas has an interesting but limited potential